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Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 1. A 27-year-old man comes to the physician because of a 2-year history of se...

Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 1. A 27-year-old man comes to the physician because of a 2-year history of severe muscle cramping and weakness immediately following calisthenics or after jogging a short distance. The crampi ng and weakness resolve withi n 24 hours. He also has dark urine during these episodes. Neurolog ic exam ination, performed while he is asymptomatic, shows no abnormalities. Which of the following is the most likely diagnosis? A) Alcohol ic rhabdomyolysis B) Hypokalemic period ic paralysis C) Muscle phosphorylase defi ciency (McArd le disease) D) Myasthenic (Lambert-Eaton) syndrome E) Polymyositis Correct Answer: C. Muscle phosphorylase deficiency (McArdle disease) is a glycogen storage disease that affects the muscles. It is characterized by the inability of myocytes to break down glycogen as a result of the absence of muscular glycogen phosphorylase, which causes exercise intolerance with fatigue, cramping, and muscle weakness. Muscle cramping may resolve with rest or be permanent. Occasionally, a "second wind" phenomenon may be seen when blood flow to the muscles increases after approximately 10 minutes of exercise, delivering fatty acids as fuel and relieving the need for glycogen breakdown. Patients may also have episodes of rhabdomyolysis, accompanied by red or brown urine and urinalysis positive for blood resulting from the presence of myoglobinuria without microscopic evidence of red blood cells. A complication of McArdle disease is acute kidney injury and acute tubular necrosis secondary to the release of nephrotoxic myoglobin and heme pigments in rhabdomyolysis. Treatment involves avoiding low-carbohydrate diets and improving cardiovascular fitness with regular, mild aerobic exercise. Incorrect Answers: A, B, D, and E. Alcoholic rhabdomyolysis (Choice A) refers to muscle breakdown induced by excessive alcohol consumption. Rhabdomyolysis is characterized by a triad of muscle pain, weakness, and dark urine. It may also be brought on by episodes of strenuous exercise, though jogging a short distance would not be expected to cause it. Hypokalemic periodic paralysis (Choice B) is characterized by episodes of painless muscle weakness brought on by heavy exercise. Episodes occur in association with low serum potassium concentration. Exercise intolerance with muscle cramping and myoglobinuria is more suggestive of a metabolic myopathy, like McArdle disease. Myasthenic (Lambert-Eaton) syndrome (Choice D) is a paraneoplastic syndrome often caused by small cell carcinoma of the lung. Presynaptic calcium channel antibody production causes the proximal extremity weakness. A characteristic physical examination feature is the augmentation of strength with repetitive action, which is caused by progressive increases in calcium concentration..... ~, https://t.me/USMLENBME2CK ~ ~ r, Next Score Report Lab Values Calculator Help Pause Exam Section: Item 1 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment E) Polymyositis... Correct Answer: C. Muscle phosphorylase deficiency (McArdle disease) is a glycogen storage disease that affects the muscles. It is characterized by the inability of myocytes to break down glycogen as a result of the absence of muscular glycogen phosphorylase, which causes exercise intolerance with fatigue, cramping, and muscle weakness. Muscle cramping may resolve with rest or be permanent. Occasionally, a "second wind" phenomenon may be seen when blood flow to the muscles increases after approximately 10 minutes of exercise, delivering fatty acids as fuel and relieving the need for glycogen breakdown. Patients may also have episodes of rhabdomyolysis, accompanied by red or brown urine and urinalysis positive for blood resulting from the presence of myoglobinuria without microscopic evidence of red blood cells. A complication of McArdle disease is acute kidney injury and acute tubular necrosis secondary to the release of nephrotoxic myoglobin and heme pigments in rhabdomyolysis. Treatment involves avoiding low-carbohydrate diets and improving cardiovascular fitness with regular, mild aerobic exercise. Incorrect Answers: A, B, D, and E. Alcoholic rhabdomyolysis (Choice A) refers to muscle breakdown induced by excessive alcohol consumption. Rhabdomyolysis is characterized by a triad of muscle pain, weakness, and dark urine. It may also be brought on by episodes of strenuous exercise, though jogging a short distance would not be expected to cause it. Hypokalemic periodic paralysis (Choice B) is characterized by episodes of painless muscle weakness brought on by heavy exercise. Episodes occur in association with low serum potassium concentration. Exercise intolerance with muscle cramping and myoglobinuria is more suggestive of a metabolic myopathy, like McArdle disease. Myasthenic (Lambert-Eaton) syndrome (Choice D) is a paraneoplastic syndrome often caused by small cell carcinoma of the lung. Presynaptic calcium channel antibody production causes the proximal extremity weakness. A characteristic physical examination feature is the augmentation of strength with repetitive action, which is caused by progressive increases in calcium concentration. Polymyositis (Choice E) is an autoimmune condition affecting the proximal muscles. It is closely related to dermatomyositis, however, unlike dermatomyositis, it does not present with cutaneous findings. The muscular inflammation is characterized by an endomysial CD8+ T-lymphocyte inflammatory infiltrate causing damage to the myocytes. The weakness is not related to exercise and does not resolve with rest. Educational Objective: Muscle phosphorylase deficiency (McArdle disease) is a glycogen storage disease in which myocytes are unable to break down glycogen because of the absence of muscular glycogen phosphorylase. Fatigue, cramping, and muscle weakness are seen with exercise. It may be complicated by rhabdomyolysis and acute kidney injury..,. ~, https://t.me/USMLENBME2CK ~ ~ r, Next Score Report Lab Values Calculator Help Pause Exam Section: Item 2 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 2. A 77-year-old woman with mild dementia, Alzheimer type, is brought to the emergency department by her daughter 3 hours after the sudden onset of fearfulness and combativeness. The patient lives with her daughter and son-in-law. She attempted to smash their television screen with her walker and struck her son-in-law when he tried to stop her. She has hypertension, gastroesophageal reflux disease, and diverticulosis. Her medications are metoprolol, omeprazole, triamterene-hydrochlorothiazide, and donepezil. On arrival, she is hostile and accuses the physician of trying to steal her money. Her temperature is 37.5°C (99.5°F), pulse is 74/min, respirations are 16/min, and blood pressure is 144/82 mm Hg. Physical examination shows restless movements. Mental status examination initially shows hypervigilance; the patient later appears drowsy. She mutters under her breath as if responding to internal stimuli and picks at the air. Her Mini-Mental State Examination score is 10/30. Results of which of the following diagnostic studies are most likely to be abnormal in th is patient? A) Liver fu nction tests B) Measurement of serum vitamin B 12 (cobalamin) concentration C) Serum toxicology screening D) Thyroid fu nction tests E) Urinalysis Correct Answer: E. Urinalysis is likely to be abnormal in this patient with delirium, which is defined by an acute-onset alteration of consciousness and cognition, with symptoms that wax and wane throughout the day. In elderly patients, especially those with underlying dementia, systemic infection can rapidly lead to the development of delirium. Other common causes of delirium include intoxication and adverse effects from medications such as anticholinergics, benzodiazepines, or opiates. Al l patients with delirium should be evaluated for evidence of systemic infection with urinalysis and culture, chest x-ray, and occasional ly with blood cultures, if indicated. Treatment of delirium should focus on treatment of the underlying infection if one is detected, frequent reorientation, maintenance of normal sleep- wake cycles, and placement of the patient in a calm and soothing environment. Incorrect Answers: A, B, C, and D. Liver function tests (Choice A) may be abnormal in patients with acute liver failure or patients with cirrhosis who present with altered mental status. This patient has no other evidence of either acute or chronic liver failure on examination; evaluation for an underlying infection is more appropriate. Measurement of serum vitamin B 12 (cobalamin) concentration (Choice B) is unlikely to be helpful. Decreased concentrations of vitamin B 12 (cobalamin) can result in peripheral neuropathy and impaired proprioception from subacute combined degeneration of the dorsal and lateral columns of the spinal cord. Patients also frequently demonstrate a macrocytic anemia..... - -- - -- -- -- --- -- -- -- - -- -- -- - - -- - - - -- - - - -- - - - -- -- - - ---- - - - -- - - - - - - - - - - - - r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 2 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment - -... D) Thyroid function tests E) Urinalysis Correct Answer: E. Urinalysis is likely to be abnormal in this patient with delirium, which is defined by an acute-onset alteration of consciousness and cognition, with symptoms that wax and wane throughout the day. In elderly patients, especially those with underlying dementia, systemic infection can rapidly lead to the development of delirium. Other common causes of delirium include intoxication and adverse effects from medications such as anticholinergics, benzodiazepines, or opiates. Al l patients with delirium should be evaluated for evidence of systemic infection with urinalysis and culture, chest x-ray, and occasional ly with blood cultures, if indicated. Treatment of delirium should focus on treatment of the underlying infection if one is detected, frequent reorientation, maintenance of normal sleep- wake cycles, and placement of the patient in a calm and soothing environment. Incorrect Answers: A, B, C, and D. Liver function tests (Choice A) may be abnormal in patients with acute liver failure or patients with cirrhosis who present with altered mental status. This patient has no other evidence of either acute or chronic liver failure on examination; evaluation for an underlying infection is more appropriate. Measurement of serum vitamin B 12 (cobalamin) concentration (Choice B) is unlikely to be helpful. Decreased concentrations of vitamin B 12 (cobalamin) can result in peripheral neuropathy and impaired proprioception from subacute combined degeneration of the dorsal and lateral columns of the spinal cord. Patients also frequently demonstrate a macrocytic anemia. Serum toxicology screening (Choice C) is frequently performed in the evaluation of delirium when a good history cannot be obtained or when there are other signs of intoxication. This patient's caregivers did not report a recent history of substance ingestion, so a toxicology screen is unlikely to be helpful. Thyroid function tests (Choice D) are unlikely to be helpful. Patients with altered mental status from hyperthyroidism often have concomitant findings of heat intolerance, sweating, tachycardia, and hypertension, whi le patients with severe hypothyroidism present with reduced levels of consciousness, not hyperactive delirium. Educational Objective: Delirium is a common finding in elderly patients with underlying dementia who have an underlying systemic infection. Delirium is characterized by an acute-onset alteration in cognition and consciousness that fluctuates over time. Evaluation should focus on identifying the presence of any underlying infections as well as asking caregivers about recent ingestions or medication changes..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 3 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 3. A 77-year-old woman is brought to the physician by her son because she recently has become unable to take care of herself or walk independently. Her son says that her ability to function has declined during the past 4 months, but she has not had any specific complaints. She has hypertension treated with atenolol and enalapril. Her only other medication is 81-mg aspirin. Six years ago, she had a myocardial infarction. On examination, her speech is confused. Her pulse is 72/min, and blood pressure is 145/86 mm Hg. Exam ination shows diffuse muscle weakness. Gait testi ng shows an inability to ambulate. She can recall one of three objects after 2 minutes. Results of laboratory studies are within the reference ranges. An MRI of the brain shows multiple small infarctions throughout both cortices and a few in the thalamus. In addition to adjustments to her antihypertensive medications, administration of which of the following is the most appropriate management? A) Enoxaparin B) Hepari n followed by warfarin C) Vitamin E D) Warfarin only E) No additional medication is indicated Correct Answer: E. Multi-infarct (vascular) dementia refers to cognitive impairment that results from acute cerebral infarctions secondary to underlying cerebrovascular or thromboembolic disease. Patients with vascular dementia typically possess a history of clinical strokes with consequent focal neurologic deficits and a stepwise decline in function. Some patients alternatively demonstrate si lent cerebrovascular disease, characterized by progressive neurologic decline and mu ltiple small infarcts on neuroimaging, as in th is patient. This patient possesses risk factors for cerebrovascular disease such as hypertension and atherosclerotic disease (as evidenced by a prior myocardial infarction). Diagnosis requires evidence of cerebrovascular disease (eg, clinical history of stroke or neuroimaging evidence of infarct) and cognitive impairment. Management requ ires secondary prevention of stroke via blood pressure control. In al l patients with a stroke history and many patients with si lent cerebrovascular disease, antiplatelet therapy with aspirin is required. However, th is patient is already on aspirin for the secondary prevention of myocardial infarction, thus no additional medication is indicated. Incorrect Answers: A, B, C, and D. Long-term antithrombotic therapy in the form of enoxaparin (Choice A), heparin fol lowed by warfarin (Choice B), and warfarin on ly (Choice D) would be appropriate after acute ischemic stroke related to atrial fibril lation, left ventricular thrombus, or valve replacement. This patient does not possess a history of acute ischemic stroke (eg, an abrupt neurologic change) but instead presents with silent cerebrovascular disease, and she does not demonstrate evidence of cardiac indications for chronic anticoagulation. Supplementation of vitamin E (Choice C), an antioxidant, has not proven effective for the primary or secondary prevention of cardiovascular or cerebrovascular disease..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 3 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment --. - -...... -- - -- -.. - --- - -... - ,. --. - the brain shows multiple smal l infarctions throughout both cortices and a few in the thalamus. In addition to adj ustments to her antihypertensive... med ications, admin istration of wh ich of the following is the most appropriate management? A) Enoxaparin B) Hepari n followed by warfarin C) Vitam in E D) Warfarin only E) No additional medication is indicated Correct Answer: E. Multi-infarct (vascular) dementia refers to cognitive impairment that results from acute cerebral infarctions secondary to underlying cerebrovascular or thromboembolic disease. Patients with vascular dementia typically possess a history of clinical strokes with consequent focal neurologic deficits and a stepwise decline in function. Some patients alternatively demonstrate si lent cerebrovascular disease, characterized by progressive neurologic decline and mu ltiple small infarcts on neuroimaging, as in this patient. This patient possesses risk factors for cerebrovascular disease such as hypertension and atherosclerotic disease (as evidenced by a prior myocardial infarction). Diagnosis requires evidence of cerebrovascular disease (eg, clinical history of stroke or neuroimaging evidence of infarct) and cognitive impairment. Management requires secondary prevention of stroke via blood pressure control. In al l patients with a stroke history and many patients with si lent cerebrovascular disease, antiplatelet therapy with aspirin is required. However, this patient is already on aspirin for the secondary prevention of myocardial infarction, thus no additional medication is indicated. Incorrect Answers: A, B, C, and D. Long-term antithrombotic therapy in the form of enoxaparin (Choice A), heparin fol lowed by warfarin (Choice B), and warfarin on ly (Choice D) would be appropriate after acute ischemic stroke related to atrial fibril lation, left ventricular thrombus, or valve replacement. This patient does not possess a history of acute ischemic stroke (eg, an abrupt neurologic change) but instead presents with silent cerebrovascular disease, and she does not demonstrate evidence of cardiac indications for chronic anticoagulation. Supplementation of vitamin E (Choice C), an antioxidant, has not proven effective for the primary or secondary prevention of cardiovascular or cerebrovascular disease. Educational Objective: Vascular dementia refers to cognitive impairment that results from a history of stroke or silent cerebrovascu lar disease (small infarcts on neuroimaging without a history of acute neurologic symptoms). Patients typically present with stepwise cognitive decline and focal neurologic deficits, though patients with silent cerebrovascular disease may instead present with progressive neurologic decline. Management requires secondary prevention with antihypertensive and antiplatelet therapy..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 4 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment The response options for the next 2 items are the same. Select one answer for each item in the set. For each patient with a visual disturbance, select the most likely site of the lesion. A) Cerebellum B) Cranial nerve 11 C) Cranial nerve 11 1 D) Cranial nerve IV E) Cranial nerve VI F) Extraocular muscles G) Medial long itudinal fascicu lus H) Neuromuscular junction I) Retina 4. A 62-year-old woman is brought to the emergency department 3 hours after the onset of double vision and left eye pain that she first noted when she awoke. She describes a horizontal separation of images, which is worse for distant as opposed to near vision. She has an 18-year history of type 2 diabetes mellitus. Examination of the left eye shows mild adduction on primary gaze with severe weakness of abduction with conjugate gaze to the left. The remainder of the neurologic examination shows no abnormalities. Correct Answer: E. Microvascular damage resulting from diabetes mel litus can produce neuropathy, such as distal polyneuropathy, radiculopathy or, as in this case, cranial nerve palsy. Common ly affected nerves include the abducens nerve (cranial nerve VI), which presents with esotropia, unilateral abduction deficit, and diplopia in horizontal gaze, and the oculomotor nerve (cranial nerve Ill), which presents with unilateral ptosis, exotropia, and hypotropia. Patients may experience associated ocular or periocular pain. It is important to exclude other possible causes of cranial nerve palsy, such as stroke, increased intracranial pressure, vascu litis, or optic neuropathy. Most patients with microvascular abducens nerve palsy experience resolution of symptoms over several months fol lowing treatment of the underlying cause. Incorrect Answers: A, B, C, D, F, G, H, and I. The cerebellum (Choice A) contains a variety of structures, including the vermis, floccu lus, and paraflocculus, which are important for the coordination of ocular saccades, pursuit movements, and gaze holding. Cerebellar lesions do not produce esotropia..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 4 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt... Microvascular damage resulting from diabetes mel litus can produce neuropathy, such as distal polyneuropathy, radiculopathy or, as in this case, cranial nerve palsy. Common ly affected nerves include the abducens nerve (cranial nerve VI), which presents with esotropia, unilateral abduction deficit, and diplopia in horizontal gaze, and the oculomotor nerve (cranial nerve Ill), which presents with unilateral ptosis, exotropia, and hypotropia. Patients may experience associated ocular or periocular pain. It is important to exclude other possible causes of cranial nerve palsy, such as stroke, increased intracranial pressure, vascu litis, or optic neuropathy. Most patients with microvascular abducens nerve palsy experience resolution of symptoms over several months fol lowing treatment of the underlying cause. Incorrect Answers: A, B, C, D, F, G, H, and I. The cerebellum (Choice A) contains a variety of structures, including the vermis, floccu lus, and paraflocculus, which are important for the coordination of ocular saccades, pursuit movements, and gaze holding. Cerebellar lesions do not produce esotropia. Cranial nerve II (Choice B), the optic nerve, carries visual sensory information from the retina to the primary visual cortex via the lateral geniculate nucleus. Optic nerve defects can be caused by demyelination or trauma and present with monocular vision loss. Cranial nerve Ill (Choice C), the oculomotor nerve, is responsible for motor innervation of the levator palpebrae superioris, the superior, medial, and inferior rectus muscles, as well as the inferior oblique muscle. Deficits of the oculomotor nerve present with ptosis, exotropia, and hypotropia. Cranial nerve IV (Choice D), the troch lear nerve, is responsible for motor innervation of the superior oblique muscle. Deficits of the troch lear nerve present with diplopia, hypertropia, and compensatory head ti lt. Extraocular muscles (Choice F) may cause diplopia in thyroid ophthalmopathy, orbital mass lesions, or entrapment within a fractured orbital bone. This patient's history of diabetes mellitus suggests microvascular ischemia as a more likely cause of her diplopia. Lesions of the medial longitudinal fascicu lus (MLF) (Choice G) cause internuclear ophthalmoplegia (INO), which presents with an ipsilateral adduction deficit, characterized by an inability of the affected eye to cross mid line, and an associated contralateral abduction saccade (as the contralateral eye undergoes more rapid nerve firing to attempt to pu ll the ipsilateral eye across the midline). Defects of the neuromuscular junction (Choice H) occur in myasthenia gravis, which presents with diplopia and ptosis that worsens towards the end of the day. Defects of the retina (Choice I) may produce visual disturbances but do not cause acute onset diplopia or deficits of extraocular movements. Educational Objective: Diabetes mellitus causes microvascular damage to a variety of tissues, including nerves, and can cause cranial nerve palsy. Microvascular abducens nerve palsy presents with esotropia, unilateral abduction deficit, and diplopia in horizontal gaze. Most patients experience spontaneous recovery over several months following treatment of the underlying cause..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment For each patient with a visual disturbance, select the most likely site of the lesion. A) Cerebellum B) Cranial nerve 11 C) Cranial nerve 11 1 D) Cranial nerve IV E) Cranial nerve VI F) Extraocu lar muscles G) Medial longitudinal fa sciculus H) Neuromuscular junction I) Reti na 5. A 35-year-old man comes to the physician 1 day after the sudden onset of double vision. He describes seeing two objects side by side that are farthest apart when he looks to the ri ght. Exam ination shows the eyes move normally w hen looking to the left. When looking to the ri ght, the left eye does not fully adduct, and there is nystagmus in the abducting eye. T he remainder of the neurologic examination shows no abnormalities. Correct Answer: G. The medial longitudinal fascicu lus (MLF) contains interneurons that al low coordination of the oculomotor nucleus with the contralateral paramedian pontine reticular formation and abducens nucleus. During horizontal eye movements, abduction requires close coordination between the abducens and oculomotor nuclei. For example, during left gaze, impulses from cortical centers travel through the left paramedian pontine reticular formation to the left abducens nucleus, resu lting in abduction of the left eye. Conjugate gaze requires symmetric adduction of the right eye via the right ocu lomotor nucleus. Lesions of the MLF cause internuclear ophthalmoplegia (INO), which presents with an ipsilateral adduction deficit, characterized by an inability of the affected eye to cross midline, and an associated contralateral abduction saccade (as the contralateral eye undergoes more rapid neural stimu lation in an attempt to pull the ipsilateral eye across the mid line). INO may be unilateral or bilateral. In younger patients, such as in this patient, demyelination associated with multiple sclerosis is the most common cause, whereas ischemic stroke is the most common cause in older patients. Incorrect Answers: A, B, C, D, E, F, H, and I. The cerebellum (Choice A) contains a variety of structures, including the vermis, floccu lus, and paraflocculus, which are important for the coordination of ocular saccades, pursuit movements, and gaze holding. Cerebellar lesions do not produce INO..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Correct Answer: G.... The medial longitudinal fasciculus (MLF) contains interneurons that al low coordination of the oculomotor nucleus with the contralateral paramedian pontine reticular formation and abducens nucleus. During horizontal eye movements, abduction requires close coordination between the abducens and oculomotor nuclei. For example, during left gaze, impulses from cortical centers travel through the left paramedian pontine reticular formation to the left abducens nucleus, resulting in abduction of the left eye. Conjugate gaze requires symmetric adduction of the right eye via the right oculomotor nucleus. Lesions of the MLF cause internuclear ophthalmoplegia (INO), which presents with an ipsilateral adduction deficit, characterized by an inability of the affected eye to cross midline, and an associated contralateral abduction saccade (as the contralateral eye undergoes more rapid neural stimu lation in an attempt to pull the ipsilateral eye across the midline). INO may be unilateral or bilateral. In younger patients, such as in this patient, demyelination associated with multiple sclerosis is the most common cause, whereas ischemic stroke is the most common cause in older patients. Incorrect Answers: A, B, C, D, E, F, H, and I. The cerebellum (Choice A) contains a variety of structures, including the vermis, flocculus, and paraflocculus, which are important for the coordination of ocular saccades, pursuit movements, and gaze holding. Cerebellar lesions do not produce INO. Cranial nerve II (Choice B), the optic nerve, carries visual sensory information from the retina to the primary visual cortex via the lateral geniculate nucleus. Optic nerve defects can be caused by demyelination or trauma and present with monocular vision loss. Cranial nerve Ill (Choice C), the oculomotor nerve, is responsible for motor innervation of the levator palpebrae superioris, the superior, medial, and inferior rectus muscles, as well as the inferior oblique muscle. Deficits of the oculomotor nerve present with ptosis, exotropia, and hypotropia. Cranial nerve IV (Choice D), the trochlear nerve, is responsible for motor innervation of the superior oblique muscle. Deficits of the trochlear nerve present with diplopia, hypertropia, and compensatory head tilt. Cranial nerve VI (Choice E), the abducens nerve, is responsible for motor innervation of the lateral rectus muscle. Deficits of the abducens nerve present with esotropia and diplopia in horizontal gaze. Adduction is not affected by abducens nerve palsy. Extraocular muscles (Choice F) may cause diplopia in thyroid ophthalmopathy, orbital mass lesions, or entrapment within a fractured orbital bone. This patient lacks suggestive signs or risk factors for these etiologies, suggesting INO as a more likely cause of his diplopia. Defects of the neuromuscular junction (Choice H) occur in myasthenia gravis, which presents with diplopia and ptosis that worsens towards the end of the day. Defects of the retina (Choice I) may produce visual disturbances but do not cause acute onset diplopia or deficits of extraocular movements. Educational Objective: The medial longitudinal fasciculus (MLF) contains interneurons that allow coordinated, conjugate, horizontal gaze.... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 5 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment pontine reticular formation and abducens nucleus. During horizontal eye movements, abduction requires close coordination between the abducens... and oculomotor nuclei. For example, during left gaze, impulses from cortical centers travel through the left paramedian pontine reticular formation to the left abducens nucleus, resulting in abduction of the left eye. Conjugate gaze requires symmetric adduction of the right eye via the right oculomotor nucleus. Lesions of the MLF cause internuclear ophthalmoplegia (INO), which presents with an ipsilateral adduction deficit, characterized by an inability of the affected eye to cross midline, and an associated contralateral abduction saccade (as the contralateral eye undergoes more rapid neural stimulation in an attempt to pull the ipsilateral eye across the midline). INO may be unilateral or bilateral. In younger patients, such as in this patient, demyelination associated with multiple sclerosis is the most common cause, whereas ischemic stroke is the most common cause in older patients. Incorrect Answers: A, B, C, D, E, F, H, and I. The cerebellum (Choice A) contains a variety of structures, including the vermis, flocculus, and paraflocculus, which are important for the coordination of ocular saccades, pursuit movements, and gaze holding. Cerebellar lesions do not produce INO. Cranial nerve II (Choice B), the optic nerve, carries visual sensory information from the retina to the primary visual cortex via the lateral geniculate nucleus. Optic nerve defects can be caused by demyelination or trauma and present with monocular vision loss. Cranial nerve Ill (Choice C), the oculomotor nerve, is responsible for motor innervation of the levator palpebrae superioris, the superior, medial, and inferior rectus muscles, as well as the inferior oblique muscle. Deficits of the oculomotor nerve present with ptosis, exotropia, and hypotropia. Cranial nerve IV (Choice D), the trochlear nerve, is responsible for motor innervation of the superior oblique muscle. Deficits of the trochlear nerve present with diplopia, hypertropia, and compensatory head tilt. Cranial nerve VI (Choice E), the abducens nerve, is responsible for motor innervation of the lateral rectus muscle. Deficits of the abducens nerve present with esotropia and diplopia in horizontal gaze. Adduction is not affected by abducens nerve palsy. Extraocu lar muscles (Choice F) may cause diplopia in thyroid ophthalmopathy, orbital mass lesions, or entrapment within a fractured orbital bone. This patient lacks suggestive signs or risk factors for these etiologies, suggesting INO as a more likely cause of his diplopia. Defects of the neuromuscular junction (Choice H) occur in myasthenia gravis, which presents with diplopia and ptosis that worsens towards the end of the day. Defects of the retina (Choice I) may produce visual disturbances but do not cause acute onset diplopia or deficits of extraocular movements. Educational Objective: The medial longitudinal fasciculus (MLF) contains interneurons that allow coordinated, conjugate, horizontal gaze movements by connecting the oculomotor nucleus with the contralateral paramedian pontine reticular formation and abducens nucleus. Lesions of the MLF cause internuclear ophthalmoplegia (INO), which presents with an ipsilateral adduction deficit, characterized by an inability of the affected eye to cross midline, and an associated contralateral abduction saccade..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 6 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 6. A 47-year-old woman with chronic alcoholism is brought to the emergency department acutely intoxicated. Other than her intoxication, physical and neurologic examinations show no abnormalities. Which of the following complications is most likely to be prevented by immediate administration of vitamin B 1 (thiamine)? A) Acute alcoholic myopathy B) Anterograde amnesi C) Burning paresthesias of the feet D) Hallucinations E) Seizures Correct Answer: B. Patients who chronical ly use alcohol typical ly demonstrate a significant vitamin B 1 (thiamine) deficiency caused by poor nutritional intake, thiamine malabsorption, and impaired cellular utilization of thiamine. Over time, thiamine deficiency can result in damage and atrophy of the mammillary bodies, visible on MRI of the brain, which manifests as Wernicke encephalopathy. To prevent Wernicke encephalopathy, all patients with sustained heavy alcohol use should be given oral thiamine supplementation, and patients presenting with acute intoxication should generally be given parenteral thiamine. The typical clinical presentation of Wernicke encephalopathy is a triad of acutely altered mental status, ophthalmoplegia (along with nystagmus), and ataxia. The symptoms of Wernicke encephalopathy are reversible but increase the risk for developing Wernicke-Korsakoff syndrome in patients with alcohol use disorder if not immediately treated with high-dose parenteral thiamine. Wernicke-Korsakoff syndrome is an irreversible condition that features psychosis, anterograde and retrograde amnesia, and the consequent tendency to confabulate, or verbalize false stories or memories, to compensate for the inability to remember. Incorrect Answers: A, C, D, and E. Acute alcoholic myopathy (Choice A) is a complication of chronic alcohol use (especially in binge-pattern use) that likely results from alcohol's effect on the permeability of the skeletal muscle cell membrane, manifesting as muscle pain and swel ling. Thiamine supplementation does not decrease the risk for acute alcoholic myopathy. Burning paresthesias of the feet (Choice C) may occur as a manifestation of subacute combined degeneration, resu lting from vitamin B 12 (cobalamin) deficiency, or from alcoholic neuropathy. Though patients who use alcohol chronically may have vitamin B 12 deficiency caused by malnutrition, the administration of vitamin B 1 (thiamine) would not prevent complications of vitamin B 12 deficiency. Hallucinations (Choice D) may occur in alcohol withdrawal as a manifestation of alcoholic hallucinosis or delirium tremens. Hallucinations are not a typical feature of Wernicke-Korsakoff syndrome and would not be prevented by thiamine administration..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 6 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment E) Seizures... Correct Answer: B. Patients who chronical ly use alcohol typical ly demonstrate a significant vitamin B 1 (thiamine) deficiency caused by poor nutritional intake, thiamine malabsorption, and impaired cellular utilization of thiamine. Over time, thiamine deficiency can result in damage and atrophy of the mammillary bodies, visible on MRI of the brain, which manifests as Wernicke encephalopathy. To prevent Wernicke encephalopathy, all patients with sustained heavy alcohol use should be given oral thiamine supplementation, and patients presenting with acute intoxication should generally be given parenteral thiamine. The typical clinical presentation of Wernicke encephalopathy is a triad of acutely altered mental status, ophthalmoplegia (along with nystagmus), and ataxia. The symptoms of Wernicke encephalopathy are reversible but increase the risk for developing Wernicke-Korsakoff syndrome in patients with alcohol use disorder if not immediately treated with high-dose parenteral thiamine. Wernicke-Korsakoff syndrome is an irreversible condition that features psychosis, anterograde and retrograde amnesia, and the consequent tendency to confabulate, or verbalize false stories or memories, to compensate for the inability to remember. Incorrect Answers: A, C, D, and E. Acute alcoholic myopathy (Choice A) is a complication of chronic alcohol use (especially in binge-pattern use) that likely results from alcohol's effect on the permeability of the skeletal muscle cell membrane, manifesting as muscle pain and swel ling. Thiamine supplementation does not decrease the risk for acute alcoholic myopathy. Burning paresthesias of the feet (Choice C) may occur as a manifestation of subacute combined degeneration, resu lting from vitamin B 12 (cobalamin) deficiency, or from alcoholic neuropathy. Though patients who use alcohol chronically may have vitamin B 12 deficiency caused by malnutrition, the administration of vitamin B 1 (thiamine) would not prevent complications of vitamin B 12 deficiency. Hallucinations (Choice D) may occur in alcohol withdrawal as a manifestation of alcoholic hallucinosis or delirium tremens. Hallucinations are not a typical feature of Wernicke-Korsakoff syndrome and would not be prevented by thiamine administration. Seizures (Choices E) may occur in alcohol withdrawal. Thiamine does not prevent alcohol withdrawal-induced seizures. Educational Objective: Chronic alcohol use and associated malnutrition may result in significant thiamine deficiency, which can cause Wernicke-Korsakoff syndrome. The syndrome is characterized by altered mental status, ophthalmoplegia, ataxia, psychosis, and anterograde and retrograde amnesia. Thiamine supplementation can prevent the development of Wernicke-Korsakoff syndrome in patients with alcohol use disorder..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 7 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 7. An 82-year-old woman has had a chron ic bitemporal headache and diffuse achiness of the shou lders for 6 months. She has no history of serious illness and takes no med ications. Her temperature is 37°C (98.6°F), pu lse is 80/min, respirations are 12/min, and blood pressure is 150/85 mm Hg. There is mild deformity of the distal interphalangeal joints; range of motion is full, and there is no edema or erythema of the joints. Exam ination shows normal fund i. Neurologic exam ination shows no focal findings. Erythrocyte sed imentation rate is 120 mm/h. Which of the following is the most likely diagnosis? A) Ankylosing spondylitis B) Fibromyositis C) Polymyalgia rheumatica D) Polymyositis E) Rheumatoid arthritis Correct Answer: C. Polymyalgia rheumatica (PMR) is the most likely diagnosis in this elderly woman with myalgia, bitemporal headache, and markedly increased erythrocyte sedimentation rate (ESR). PMR is an inflammatory disorder that often occurs concurrently with giant cel l arteritis (GCA), a large vessel vasculitis. Symptoms include proximal muscle and joint (eg, shoulder and hip girdle) pain and stiffness. If untreated, muscle weakness may occur from disuse atrophy. Systemic symptoms such as fatigue are commonly seen. The diagnosis is clinical, and treatment is with low-dose prednisone for up to a year. It is common for patients to respond to prednisone almost immediately, thus the absence of response should prompt consideration of a different diagnosis. As GCA occurs concurrently in up to 20% of patients who have PMR, symptoms of throbbing temporal headache, vision changes, or jaw claudication should prompt temporal artery biopsy and initiation of high-dose prednisone. Incorrect Answers: A, B, D, and E. Ankylosing spondylitis (Choice A) is a seronegative inflammatory arthritis that most commonly affects younger men with a history of chronic low back and buttock pain that is worse in the morning and improves with exercise. Concurrent findings may also include uveitis, increased inflammatory markers, and positive HLA-B27. Pelvic x-rays may show sacroiliitis, although MRI is more sensitive. Fibromyositis (Choice B), commonly known as fibromyalgia, is considered a central pain processing disorder. Patients are usually younger women who present with chronic fatigue, exercise intolerance, and diffuse or multifocal muscle tenderness in the absence of abnormal laboratory findings. This is an unlikely diagnosis in this patient. Polymyositis (Choice D) is an inflammatory myopathy that can also present with proximal muscle pain, but it is frequently accompanied by weakness. Inflammatory markers may be increased but are nonspecific. Serum creatinine kinase may also be increased and can.... , ~, -- ---- - - - ------ \j ------- - -- -- - -- - -------- ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 7 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... C) Polymyalgia rheumatica D) Polymyositis E) Rheumatoid arthritis Correct Answer: C. Polymyalgia rheumatica (PMR) is the most likely diagnosis in this elderly woman with myalgia, bitemporal headache, and markedly increased erythrocyte sedimentation rate (ESR). PMR is an inflammatory disorder that often occurs concurrently with giant cell arteritis (GCA), a large vessel vasculitis. Symptoms include proximal muscle and joint (eg, shoulder and hip girdle) pain and stiffness. If untreated, muscle weakness may occur from disuse atrophy. Systemic symptoms such as fatigue are commonly seen. The diagnosis is clinical, and treatment is with low-dose prednisone for up to a year. It is common for patients to respond to prednisone almost immediately, thus the absence of response should prompt consideration of a different diagnosis. As GCA occurs concurrently in up to 20% of patients who have PMR, symptoms of throbbing temporal headache, vision changes, or jaw claudication should prompt temporal artery biopsy and initiation of high-dose prednisone. Incorrect Answers: A, B, D, and E. Ankylosing spondylitis (Choice A) is a seronegative inflammatory arthritis that most commonly affects younger men with a history of chronic low back and buttock pain that is worse in the morning and improves with exercise. Concurrent findings may also include uveitis, increased inflammatory markers, and positive HLA-B27. Pelvic x-rays may show sacroiliitis, although MRI is more sensitive. Fibromyositis (Choice B), commonly known as fibromyalgia, is considered a central pain processing disorder. Patients are usually younger women who present with chronic fatigue, exercise intolerance, and diffuse or multifocal muscle tenderness in the absence of abnormal laboratory findings. This is an unlikely diagnosis in this patient. Polymyositis (Choice D) is an inflammatory myopathy that can also present with proximal muscle pain, but it is frequently accompanied by weakness. Inflammatory markers may be increased but are nonspecific. Serum creatinine kinase may also be increased and can provide a clue to diagnosis. Muscle biopsy is required for definitive diagnosis. Rheumatoid arthritis (RA) (Choice E) commonly presents with symmetric arthritis of the metacarpophalangeal and wrist joints in younger patients, but may also present with arthritis of the shoulder, elbow, ankles, and proximal interphalangeal joints. Laboratory studies often, but not always, show positive rheumatoid factor or anti-cyclic citrullinated peptide. This patient's age is atypical for RA. Educational Objective: PMR is an inflammatory disorder that commonly affects the elderly and presents with a markedly increased ESR (>100 mm/h), proximal muscle pain, joint stiffness, and systemic symptoms..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 8 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 8. A 57-year-old man comes to the physician because of a 1-year history of progressive difficulty hearing, especially on the right. He frequently needs to ask people to repeat what they are saying, especially children. His partner has told him that he has been increasing the volume of their television at home. The patient does not recall any related trauma or previous problems with his ears. For 20 years, he has managed a nightclub that features live performances. He has no history of serious illness. He occasionally takes aspirin, ibuprofen, or acetaminophen for headache or low back pain. There is no fam ily history of hearing loss. His pulse is 76/min and regular, and blood pressure is 124/74 mm Hg. On examination, the external ear canals and tympanic membranes appear normal. There is a small amount of cerumen in both ears. He has difficulty hearing whispered voice bilaterally, especially on the right. A vibrating tuning fork placed on the forehead is heard better on the left. Air conduction is greater than bone conduction bilaterally but clearer on the left. Which of the following is the most likely explanation for these fi ndings? A) Adverse effect of aspirin B) Loss of mobility of the auditory ossicles C) Meniere disease D) Scarring of the tympanic membranes E) Sensorineural hearing loss Correct Answer: E. This patient's history of occupational noise exposure, as well as his presenting signs and symptoms of high frequency hearing loss and normal conduction testing are consistent with a diagnosis of sensorineural hearing loss. Sensorineural hearing loss is typically caused by damage or loss of function of the hair cel ls of the organ of Corti within the inner ear. Presbycusis is the most common cause of sensorineural hearing loss and often occurs with prolonged exposure to loud noise. Examination typical ly discloses high frequency hearing loss along with a Rinne test demonstrating normal air conduction and decreased hearing in the affected ear, and a Weber test with decreased hearing in the affected ear. Incorrect Answers: A, B, C, and D. Adverse effects of aspirin (Choice A) include tinnitus and sensorineural hearing loss with high doses or prolonged dosing, which are typically reversible with cessation of aspirin usage. This patient's history of occasional aspirin usage is not suggestive of aspirin as a likely cause of his symptoms. Loss of mobility of the auditory ossicles (Choice B) is caused by otosclerosis, in which the small bones of the midd le ear undergo bony remodeling and loss of mobi lity that impairs their abi lity to transmit mechanical vibrations. Otosclerosis presents with low frequency conductive hearing loss and tinnitus. Meniere disease (Choice C) is a condition of episodic vertigo and sensorineural hearing loss that results from pressure accumu lation in.... - - - - -- -- - - - -- - -- -- - - -- -- -- - - -- --- - ---- - - - -- - - -- - - - - - - - - - - - - - - - - - - - - - - -- --- r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 8 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt... C) Meniere disease D) Scarri ng of the tympanic membranes E) Sensorineural hearing loss Correct Answer: E. This patient's history of occupational noise exposure, as well as his presenting signs and symptoms of high frequency hearing loss and normal conduction testing are consistent with a diagnosis of sensorineural hearing loss. Sensorineural hearing loss is typically caused by damage or loss of function of the hair cells of the organ of Corti within the inner ear. Presbycusis is the most common cause of sensorineural hearing loss and often occurs with prolonged exposure to loud noise. Examination typically discloses high frequency hearing loss along with a Rinne test demonstrating normal air conduction and decreased hearing in the affected ear, and a Weber test with decreased hearing in the affected ear. Incorrect Answers: A, B, C, and D. Adverse effects of aspirin (Choice A) include tinnitus and sensorineural hearing loss with high doses or prolonged dosing, which are typically reversible with cessation of aspirin usage. This patient's history of occasional aspirin usage is not suggestive of aspirin as a likely cause of his symptoms. Loss of mobility of the auditory ossicles (Choice B) is caused by otosclerosis, in which the small bones of the middle ear undergo bony remodeling and loss of mobility that impairs their ability to transmit mechanical vibrations. Otosclerosis presents with low frequency conductive hearing loss and tinnitus. Meniere disease (Choice C) is a condition of episodic vertigo and sensorineural hearing loss that results from pressure accumulation in the endolymph of the inner ear. This patient lacks vertigo and presents with symptoms that are constant and progressive rather than episodic. Scarring of the tympanic membranes (Choice D) may occur secondary to otitis externa or otitis media, and results in conductive hearing loss. Educational Objective: Sensorineural hearing loss commonly occurs as a result of presbycusis, in which the hair cells of the organ of Corti are damaged. Patients often have a history of prolonged noise exposure. Examination typically discloses high frequency hearing loss along with a Rinne test demonstrating normal air conduction and decreased hearing in the affected ear, and a Weber test with decreased hearing in the affected ear..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 9 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 9. A 77-year-old man comes to the physician because of a 3-week history of low-grade fever, fatigue, severe headache, sensitivity to brig ht light, and pain in the hips and shou lders. He has also had a 3.2-kg (7-lb) weight loss due to a decreased appetite during this period. He appears ill. His temperature is 38.2°C (100.8°F). Exam ination shows mild photophobia but no men ingeal signs. There is moderate pain on palpation of the large muscle groups of the shoulders and hips. The remainder of the examination shows no abnormalities. His hemog lobin concentration is 11.1 g/dl, leukocyte count is 11,600/mm 3 with a normal differential, and erythrocyte sedimentation rate is 85 mm/h. Which of the following is the most appropriate next step in diagnosis? A) Cerebral angiography B) MRI of the brain C) Lum bar puncture D) Nerve and muscle biopsy E) Temporal artery biopsy Correct Answer: E. This patient's presenting findings of fever, weight loss, fatigue, headache, proximal muscle pain, and photophobia are consistent with a diagnosis of giant cell arteritis (GCA). GCA is an autoimmune inflammatory vasculitis of medium and large vessels. Classic findings include systemic symptoms of fever, chills, and weight loss, headache, history of preceding transient vision loss (amaurosis fugax), jaw claudication, tenderness of the scalp, and pale optic disc edema. New headaches in an elderly patient should raise suspicion for GCA. GCA frequently occurs in association with polymyalgia rheumatica, which is characterized by stiffness and pain of proximal muscles. Results of laboratory studies show increased inflammatory markers, including erythrocyte sedimentation rate and C-reactive protein, and thrombocytosis. GCA is characterized by a predilection to involve the vessels of the head and neck, and often affects the ophthalmic artery, inflammatory occlusion of which can result in sudden, ischemic damage to the retina. Once vision loss occurs, it is typically irreversible, and is commonly followed by vision loss in the contralateral eye within days or weeks. The diagnosis is confirmed with biopsy of the temporal artery demonstrating granulomatous vasculitis. Treatment with high-dose corticosteroids should begin immediately once GCA is suspected in order to preserve vision. Corticosteroid treatment does not generally compromise biopsy results so long as the biopsy is performed within 1 to 2 weeks. Incorrect Answers: A, B, C, and D. Cerebral angiography (Choice A) is useful for the diagnosis of a carotid-cavernous fistula, which presents with headache, proptosis, and conjunctiva! injection. It is not typically used for the diagnosis of GCA. MRI of the brain (Choice B) is useful for the detection of ischemic stroke or mass lesions. It is not an optimal modality for the detection of granulomatous vascular inflammation..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section: Item 9 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt E) Temporal artery biopsy... Correct Answer: E. This patient's presenting findings of fever, weight loss, fatigue, headache, proximal muscle pain, and photophobia are consistent with a diagnosis of giant cell arteritis (GCA). GCA is an autoimmune inflammatory vasculitis of medium and large vessels. Classic findings include systemic symptoms of fever, chills, and weight loss, headache, history of preceding transient vision loss (amaurosis fugax), jaw claudication, tenderness of the scalp, and pale optic disc edema. New headaches in an elderly patient should raise suspicion for GCA. GCA frequently occurs in association with polymyalgia rheumatica, which is characterized by stiffness and pain of proximal muscles. Results of laboratory studies show increased inflammatory markers, including erythrocyte sedimentation rate and C-reactive protein, and thrombocytosis. GCA is characterized by a predilection to involve the vessels of the head and neck, and often affects the ophthalmic artery, inflammatory occlusion of which can result in sudden, ischemic damage to the retina. Once vision loss occurs, it is typically irreversible, and is commonly followed by vision loss in the contralateral eye within days or weeks. The diagnosis is confirmed with biopsy of the temporal artery demonstrating granulomatous vasculitis. Treatment with high-dose corticosteroids should begin immediately once GCA is suspected in order to preserve vision. Corticosteroid treatment does not generally compromise biopsy results so long as the biopsy is performed within 1 to 2 weeks. Incorrect Answers: A, B, C, and D. Cerebral angiography (Choice A) is useful for the diagnosis of a carotid-cavernous fistula, which presents with headache, proptosis, and conjunctiva! injection. It is not typically used for the diagnosis of GCA. MRI of the brain (Choice B) is useful for the detection of ischemic stroke or mass lesions. It is not an optimal modality for the detection of granulomatous vascular inflammation. Lumbar puncture (Choice C) is useful for the diagnosis of meningitis, idiopathic intracranial hypertension, encephalitis, multiple sclerosis, or leptomeningeal disease. GCA does not typically cause changes in intracranial pressure or cerebrospinal fluid contents. Nerve and muscle biopsy (Choice D) are useful for the diagnosis of vasculitis or myositis. These modalities have poor sensitivity for the detection of GCA, which does not typically cause nerve or muscular inflammation. Educational Objective: Giant cell arteritis is a vasculitis of medium and large vessels in elderly patients and commonly presents with systemic symptoms, headache, jaw claudication, and proximal muscle stiffness (PMR). Vasculitis of the ophthalmic artery may occur and cause blindness. The diagnosis is confirmed with biopsy of the temporal artery demonstrating granulomatous vasculitis. Immediate high-dose corticosteroid treatment should begin once the diagnosis is suspected and does not generally compromise biopsy results as long as the biopsy is performed within 1 to 2 weeks..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 10 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 10. A previously healthy 42-year-old man comes to the physician because of a 1-week history of moderate back pain. The pain originates in his right buttock and radiates down the posterior thigh and calf to the back of his foot. He has not had any changes in bladder or bowel fu nction. He has no history of trauma to the back. His pulse is 82/min, respirations are 16/min, and blood pressure is 132/84 mm Hg. Sensation to lig ht touch is decreased over the right posterior leg and lateral foot. Muscle strength and deep tendon reflexes are normal. Which of the following is the most appropriate next step in management? A) Myelography B) Gabapentin therapy C) Ibuprofen therapy; D) Prednisone therapy E) Nerve conduction studies Correct Answer: C. Ibuprofen therapy is the most appropriate next step in management of this patient who has signs and symptoms consistent with a right S 1 radiculopathy. Radiculopathy refers to the neurologic symptoms secondary to the compression of spinal nerve roots either as a result of a herniated intervertebral disc, a narrow or stenotic neural foramen, or compression from extrinsic sources such as tumors or infection. Patients present with pain and occasionally with weakness in the dermatome and/or myotome supplied by the affected nerve root. Radiculopathy is most common in the lumbosacral region. This patient, who presents with sensory changes affecting the buttocks, posterior leg, and lateral foot most likely has radiculopathy from compression of the S1 nerve root. The presence of sensory symptoms in the absence of motor symptoms suggests compression of the posterior nerve root, as this contains sensory fibers. Compression leads to edema and inflammation of the nerve root and surrounding structures, which causes pain. This is most effectively treated with anti-inflammatory medications such as ibuprofen. Over time, most patients will improve with conservative care and graded exercise or physical therapy. Incorrect Answers: A, B, D, and E. Myelography (Choice A) involves the injection of intrathecal contrast under fluoroscopy to assess for sites of abnormal thecal sac and neural foraminal narrowing. It is unnecessary in this case as the diagnosis can be made with physical examination alone. Gabapentin therapy (Choice B) is commonly used in patients with painful peripheral neuropathy. It does not treat the underlying inflammation associated with radiculopathy and is not considered first-line therapy. Prednisone therapy (Choice D) is not the correct answer. While glucocorticoids such as dexamethasone are sometimes used for patients with acute spinal cord compression from trauma or expanding tumors, there are many adverse effects associated with.... - -- --- -- -- - - -- -- - -- - - -- - - -- - - - - - - - - - -- -- - - - - -- r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 10 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt... Correct Answer: C. Ibuprofen therapy is the most appropriate next step in management of this patient who has signs and symptoms consistent with a right S 1 radiculopathy. Radiculopathy refers to the neurologic symptoms secondary to the compression of spinal nerve roots either as a result of a herniated intervertebral disc, a narrow or stenotic neural foramen, or compression from extrinsic sources such as tumors or infection. Patients present with pain and occasionally with weakness in the dermatome and/or myotome supplied by the affected nerve root. Radiculopathy is most common in the lumbosacral region. This patient, who presents with sensory changes affecting the buttocks, posterior leg, and lateral foot most likely has radiculopathy from compression of the S1 nerve root. The presence of sensory symptoms in the absence of motor symptoms suggests compression of the posterior nerve root, as this contains sensory fibers. Compression leads to edema and inflammation of the nerve root and surrounding structures, which causes pain. This is most effectively treated with anti-inflammatory medications such as ibuprofen. Over time, most patients will improve with conservative care and graded exercise or physical therapy. Incorrect Answers: A, B, D, and E. Myelography (Choice A) involves the injection of intrathecal contrast under fluoroscopy to assess for sites of abnormal thecal sac and neural foraminal narrowing. It is unnecessary in this case as the diagnosis can be made with physical examination alone. Gabapentin therapy (Choice B) is commonly used in patients with painful peripheral neuropathy. It does not treat the underlying inflammation associated with radiculopathy and is not considered first-line therapy. Prednisone therapy (Choice D) is not the correct answer. While glucocorticoids such as dexamethasone are sometimes used for patients with acute spinal cord compression from trauma or expanding tumors, there are many adverse effects associated with glucocorticoids. This patient's radiculopathy is more appropriately treated with ibuprofen. Nerve conduction studies (Choice E) can be performed in instances where the examination findings are not diagnostically helpful. In this case, nerve conduction studies would confirm an S1 radiculopathy, but they are not necessary as the diagnosis can be made by physical examination alone. Educational Objective: Lumbosacral radiculopathy is a common condition and can result in pain and/or weakness in areas supplied by the affected nerve root. S1 radiculopathy results in pain and sensory changes in the posterior leg and lateral foot. If the motor nerve root is affected, weakness of plantar flexion and absence of the Achilles reflex are typical. Treatment involves the use of ibuprofen or a similar non-steroidal anti-inflammatory drug. Over time, most patients will improve with conservative care and graded exercise or physical therapy..,. r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 11. A 4 ?-year-old woman is brought to the physician because of progressive loss of visual acu ity over the past 6 months. Snel len chart testing shows a visual acuity of 20/180. A photograph of the optic fu ndus is shown. The remainder of the exam ination shows no abnormalities. Wh ich of the following is the most likely cause of these findings? A) Acute glaucoma B) Detached retina C) Diabetic retinopathYi D) Macular degeneration E) Optic neuritis Correct Answer: C. This patient's fundus findings of intraretinal hemorrhage, retinal nerve fiber layer infarctions, exudates, and multiple foci of neovascularization along the superior arcade are suggestive of proliferative diabetic retinopathy. Chronic hyperglycemia caused by poorly control led diabetes mellitus results in deposition of advanced glycation end products within capi llary vessels, leading to microvascular damage. Within the retina, this process results in retinal ischemia and clinical signs of microvascu lar damage such as microaneurysms, retinal hemorrhage, retinal nerve fiber layer infarctions, and intraretinal edema and exudate deposition. These findings are characteristic of the several stages of non-proliferative diabetic retinopathy. Once retinal ischemia becomes sufficiently severe, the increased production of vascular endothelial growth factor (VEGF) by the ischemic retina leads to retinal neovascularization, the hallmark of proliferative diabetic retinopathy. Neovascularization may lead to tractional retinal detachment, vitreous hemorrhage, and neovascular glaucoma, and it may cause permanent blindness. Non-proliferative diabetic retinopathy is treated with rigorous glycemic control. Once neovascularization occurs, patients are treated with either intravitreal injections of monoclonal antibodies against VEGF (eg, bevacizumab, ranibizumab, aflibercept) or argon laser panretinal photocoagulation to reduce the intraocular burden of VEGF.... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment This patient's fundus findings of intraretinal hemorrhage, retinal nerve fiber layer infarctions, exudates, and multiple foci of neovascularization along the superior arcade are suggestive of proliferative diabetic retinopathy. Chronic hyperglycemia caused by poorly controlled diabetes mellitus results in deposition of advanced glycation end products within capillary vessels, leading to microvascular damage. Within the retina, this process results in retinal ischemia and clinical signs of microvascular damage such as microaneurysms, retinal hemorrhage, retinal nerve fiber layer infarctions, and intraretinal edema and exudate deposition. These findings are characteristic of the several stages of non-proliferative diabetic retinopathy. Once retinal ischemia becomes sufficiently severe, the increased production of vascular endothelial growth factor (VEGF) by the ischemic retina leads to retinal neovascularization, the hallmark of proliferative diabetic retinopathy. Neovascularization may lead to tractional retinal detachment, vitreous hemorrhage, and neovascular glaucoma, and it may cause permanent blindness. Non-proliferative diabetic retinopathy is treated with rigorous glycemic control. Once neovascularization occurs, patients are treated with either intravitreal injections of monoclonal antibodies against VEGF (eg, bevacizumab, ranibizumab, aflibercept) or argon laser panretinal photocoagulation to reduce the intraocular burden of VEGF and to prevent the complications of neovascularization. Incorrect Answers: A, B, D, and E. Acute glaucoma (Choice A) typically presents with pain, conjunctiva! injection, a fixed, mid-dilated pupil, increased intraocular pressure, and no visible fundus abnormalities. Optic nerve cupping is a feature of retinal ganglion cell loss resulting from increased intraocular pressure, but it typically does not manifest for months after an episode of acute angle closure glaucoma. A detached retina (Choice B) presents with decreased visual acuity and a visible region of subretinal fluid. In tractional retinal detachment caused by diabetes mellitus, the traction is produced by a visible area of fibrovascular proliferation extending from the retinal surface into the.... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 11 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment Please Walt and to prevent the complications of neovascularization.... Incorrect Answers: A, B, D, and E. Acute glaucoma (Choice A) typically presents with pain, conjunctiva! injection, a fixed, mid-dilated pupil, increased intraocular pressure, and no visible fundus abnormalities. Optic nerve cupping is a feature of retinal ganglion cell loss resulting from increased intraocular pressure, but it typical ly does not manifest for months after an episode of acute angle closure glaucoma. A detached retina (Choice B) presents with decreased visual acuity and a visible region of subretinal fluid. In tractional retinal detachment caused by diabetes mellitus, the traction is produced by a visible area of fibrovascular proliferation extending from the retinal surface into the vitreous space. Macular degeneration (Choice D) is caused by dysfunction of the retinal pigment epithelium and presents with signs and symptoms of visual distortion, scotoma, drusen, geographic atrophy, and neovascu larization. Optic neuritis (Choice E) presents with acute onset vision loss, relative afferent pupillary defect, and pain exacerbated by extraocular movements. It is often caused by demyelination and is potentially associated with the subsequent development of multiple sclerosis. Fundus findings are often normal but may include optic disc edema. Educational Objective: Diabetic retinopathy results from microvascular damage and retinal ischemia, and is characterized by microaneurysms, retinal hemorrhage, retinal nerve fiber layer infarctions, intraretinal edema and exudate deposition, and retinal neovascularization. Patients require strict glycemic control, while patients who manifest neovascularization require either intravitreal injections of monoclonal antibodies against VEGF or argon laser panretinal photocoagulation to reduce the intraocular burden of VEGF and to prevent the complications of neovascularization..... r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 12 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment 12. A 42-year-old man, who immigrated to the USA 3 years ago, tells his physician that his hands are numb. He is being treated with isoniazid for tuberculosis. His features are mildly coarsened. Exam ination shows widespread patches of loss of pinprick and light touch sensations, especially over the tip of the nose and the ears. The patches are oval or irregular and measure 2 to 3 cm. The common peroneal nerves feel thickened. Which of the following is the most likely diagnosis? A) Acute intermittent porphyria B) Alcoholic neuropathy C) Charcot-Marie-Tooth disease D) Diabetic amyotrophy E) Guillain-Barre syndrome F) LeprosYi G) Motor neuropathy with conduction block H) Paraneoplastic neuropathy I) Paraproteinemic neuropathy Correct Answer: F. Leprosy is a mycobacterial disease involving the skin and peripheral nerves, as the involved mycobacterium has a predilection for the cooler areas of the body. The disease is endemic to developing countries. Patients typically present with pigmented, hypoesthetic skin lesions with associated paresthesia along with thickened nerves and sensorimotor neuropathy, likely as a result of an immune response leading to segmental demyelination. The most commonly affected nerves are the ulnar, median, common peroneal, facial, and greater auricular nerves. Presentations range from one or a few well-demarcated skin lesions with associated focal neuropathy (known as tuberculoid disease) to diffuse skin lesions and neuropathy (known as lepromatous disease). If left untreated, neuropathy can progress and cause permanent disability, and skin lesions can become nodular and repeatedly ulcerate, which may lead to coarsened facial features. Diagnosis is made by skin biopsy showing acid-fast bacilli within a cutaneous nerve. Treatment requires dapsone and rifampin, along with clofazimine in lepromatous disease. Neuritis is treated with steroids. Incorrect Answers: A, B, C, D, E, G, H, and I. Acute intermittent porphyria (Choice A) refers to the abnormal accumulation of the red blood cell protein porphyrin and is characterized by episodic abdominal pain, polyneuropathy, psychological symptoms, and port wine-colored urine. The associated polyneuropathy typically presents as acute sensory and motor neuropathy of the extremities. Skin patches and coarse facial features would be atypical..... I ~ ' r ~, ~ ~ r, Previous Next Score Report https://t.me/USMLENBME2CK Lab Values Calculator Help Pause Exam Section : Item 12 of 50 National Board of Medical Examiners Mark Clinical Neurology Self-Assessment... Correct Answer: F. Leprosy is a mycobacterial disease involving the skin and peripheral nerves, as the involved mycobacterium has a predilection for the cooler areas of the body. The disease is endemic to developing countries. Patients typically present with pigmented, hypoesthetic skin lesions with associated paresthesia along with thickened nerves and sensorimotor neuropathy, likely as a result of an immune response leading to segmental demyelination. The most commonly affected nerves are the ulnar, median, common peroneal, facial, and greater auricular nerves. Presentations range from one or a few well-demarcated skin lesions with associated focal neuropathy (known as tuberculoid disease) to diffuse skin lesions and neuropathy (known as lepromatous disease). If left untreated, neuropathy can progress and cause permanent disability, and skin lesions can become nodular and repeatedly ulcerate, which may lead to coarsened facial features. Diagnosis is made by skin biopsy showing acid-fast bacilli within a cutaneous nerve. Treatment requires dapsone and rifampin, along with clofazimine in lepromatous disease. Neuritis is treated with steroids. Incorrect Answers: A, B, C, D, E, G, H, and I. Acute intermittent porphyria (Choice A) refers to the abnormal accumulation of the red blood cell protein porphyrin and is char