MRCP Part 1 & 2 Notes PDF

1 Notes & Notes For MRCP part I & 11 By Dr. Yousif Abdallah Hamad  2 [email protected] https://www.facebook.com/dryousif23  3 Always Remember (The Devil is in the Details) ...

1 Notes & Notes For MRCP part I & 11 By Dr. Yousif Abdallah Hamad  2 [email protected] https://www.facebook.com/dryousif23  3 Always Remember (The Devil is in the Details)  4 The main Sources of this Notes & Notes  5 The contents Section Page Neurology 5 Endocrinology 180 Cardiology 464 Respiratory 608 Gastroenterology 794 Renal 925 Rheumatology 1035 Haematology 1134 Infectious 1245 Minor Dermatology 1354 Ophthalmology 1427 Psychiatry 1479 Basics Cell biology 1517 Biochemistry and metabolism 1543 Immunology 1581 Genetics 1635 Statistics 1665 Pharmacology 1694 Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad  6 Neurology Notes & Notes For MRCP part 1 & 11 By Dr. Yousif Abdallah Hamad Neurology Updated 2017 Contains: 1/ Passmedicine 2017 2/ On examination 2017 3/ Pastest 2017 4/ Red fonts --> previous exams 5/ Other updated UK sources Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 1  7 Neurology CNS anatomy Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 2  8 Neurology Foramina of the skull Questions asking about foramina of the skull have come up in the exam in previous years. Below is a brief summary of the major foramina: Foramen Bone Vessels Nerves Optic canal Sphenoid Ophthalmic artery Optic nerve (II) Superior Sphenoid Superior ophthalmic vein Oculomotor nerve (III) orbital Inferior ophthalmic vein Trochlear nerve (IV) fissure lacrimal, frontal and nasociliary branches of ophthalmic nerve (V: V1) Abducent nerve (VI) Inferior Sphenoid Inferior ophthalmic veins Zygomatic nerve and infraorbital orbital and maxilla Infraorbital artery nerve of maxillary nerve (V2) fissure Infraorbital vein Orbital branches of pterygopalatine ganglion Foramen Sphenoid - Maxillary nerve (V2) rotundum Foramen Sphenoid Accessory meningeal artery Mandibular nerve (V3) ovale Jugular Occipital and Posterior meningeal artery Glossopharyngeal nerve (IX) foramen temporal Ascending pharyngeal artery Vagus nerve (X) Inferior petrosal sinus Accessory nerve (XI) Sigmoid sinus Internal jugular vein  Right jugular foramen lesion:  palatal weakness and swallowing difficulties (IX/X),  shoulder and sternocleidomastoid weakness (due to accessory nerve (XI) involvement. Anatomy  hindbrain comprises:  myelencephalon (medulla oblongata and lower part of the fourth ventricle)  medulla oblongata opens into the fourth ventricle.  metencephalon (pons, cerebellum and intermediate part of fourth ventricle), and  Isthmus rhombencephalon.  Cranial nerve nucleus  All the nuclei except that of the trochlear nerve (CN IV) supply nerves of the same side of the body.  nucleus ambiguous  gives rise to fibres of the glossopharyngeal (IX), vagus (X), and accessory (XI) nerves.  Solitary nucleus  embedded in the medulla oblongata,  purely sensory nuclei  receives inputs from cranial nerves: facial (VII), glossopharyngeal (IX) and vagus (X).  involved in the reflexes initiated through the vagus or glossopharyngeal nerves (e.g., carotid sinus reflex, gag reflex, etc.).  specifically receives:  Taste information from the facial nerve (anterior 2/3 of the tongue), glossopharyngeal nerve (posterior 1/3) and vagus nerve (small area on the epiglottis)  general visceral sensory inputs from the chemoreceptors in the carotid body (via glossopharyngeal nerve) and aortic body (via vagus nerve) and baroreceptors in the carotid sinus (via glossopharyngeal nerve)  general visceral sensory inputs from mechanoreceptors and chemoreceptors located in the heart, lungs and gastrointestinal tract (via vagus nerve). Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 3  9 Neurology  Nucleus locus coeruleus  located in the pons  involved with the physiological responses to stress and panic.  the principal site for brain synthesis of norepinephrine (noradrenaline).  Norepinephrine also released from the adrenal medulla.  Melanin granules inside the neurons contribute to its blue colour.  In opiate withdrawal:  Opioids inhibit the firing of neurons in the locus coeruleus.  opiate withdrawal  increased activity of the locus coeruleus withdrawal symptoms.  clonidine (alpha2 adrenoceptor agonist) is used to counteract this withdrawal effect by decreasing adrenergic neurotransmission from the locus coeruleus Brain lesions The following neurological disorders/features may allow localisation of a brain lesion: Frontal lobes lesions  Difficulties with task sequencing and executive skills  Expressive (Broca's) aphasia:  located on the posterior aspect of the frontal lobe, in the inferior frontal gyrus.  Speech is non-fluent, laboured, and halting  Disinhibition  Perseveration  Anosmia  primitive reflexes (positive grasp, pout and palmomental reflexes)  inability to generate a list  Changes in personality. Parietal lobes lesions  sensory inattention (contralateral hemihypesthesia)  apraxias  astereognosis (tactile agnosia)  inferior homonymous quadrantanopia  Neglect  mild hemiparesis  parietal ataxia  Acalculia (inability to perform mental arithmetic).  Gerstmann's syndrome (lesion of dominant parietal):  Alexia (inability to read), acalculia, finger agnosia and right-left disorientation  unilateral impairment of optokinetic nystagmus.  Optokinetic nystagmus is a nystagmus that occurs in response to a rotation movement. It is present normally. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 4  10 Neurology Temporal lobes lesions Homonymous quadrantanopias PITS (Parietal-Inferior, Temporal-Superior)  Wernicke's aphasia:  this area 'forms' the speech before 'sending it' to Broca’s area.  Lesions result in word substitution, neologisms but speech remains fluent  superior homonymous quadrantanopia  auditory agnosia  prosopagnosia (difficulty recognising faces)  Memory impairment. Occipital lobes lesions  homonymous hemianopia (with macula sparing)  may present as Anton syndrome where there is blindness but the patient is unaware or denies blindness.  cortical blindness  visual agnosia  visual illusions and elementary visual hallucinations. May 2010 exam: A patient diagnosed with a glioma in the parietal lobe. Which feature is most likely to develop? Acalculia Cerebellum lesions  midline lesions:  gait and truncal ataxia  hemisphere lesions:  intention tremor,  past pointing,  dysdiadokinesis (inability to perform rapid, alternating movements),  nystagmus Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 5  11 Neurology More specific areas Area Associated conditions Medial thalamus and Wernicke and Korsakoff’s syndrome mammillary bodies of the hypothalamus Subthalamic nucleus of the basal Hemiballism ganglia Striatum (caudate nucleus) of the Huntington chorea basal ganglia Substantia nigra of the basal Parkinson's disease ganglia Amygdala Kluver-Bucy syndrome:  hypersexuality,  hyperorality (insertion of inappropriate objects in the mouth)  hyperphagia,  visual agnosia increased activation to the amygdala is associated with depression Hippocampus pathology Short term memory impairment (for example, Alzheimer's disease). Lateral geniculate nucleus visual field defect. pathology Red nucleus tremor, which is present both at rest and during action (for example, multiple sclerosis tremor). Prefrontal cortex damage disinhibition and problems with social interaction and judgement and has been implicated in schizophrenia. Left prefrontal cortex  Depression Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 6  12 Neurology Transient ischaemic attack (TIA) Definition  temporary, focal cerebral ischemia that results in brief neurologic deficits lasting < 24 hours Stroke risk assessment  ABCD2 prognostic score  ABCD2 score is used to determine the risk for stroke in the days following a (TIA)  This gives a total score ranging from 0 to 7. Criteria Points A Age >= 60 years 1 B Blood pressure >= 140/90 mmHg 1 C Clinical features - Unilateral weakness 2 - Speech disturbance, no weakness 1 D Duration of symptoms - > 60 minutes 2 - 10-59 minutes 1 Patient has diabetes 1  Interpretation of ABCD2 risk score  If the ABCD2 risk score is 4 or above  high risk of stroke  should have:  aspirin (300 mg daily) started immediately  specialist assessment and investigation within 24 hours of onset of symptoms  measures for secondary prevention introduced as soon as the diagnosis is confirmed, including discussion of individual risk factors  If the ABCD2 risk score is 3 or below  low risk of stroke  specialist assessment within 1 week of symptom onset, including decision on brain imaging  if vascular territory or pathology is uncertain, refer for brain imaging  People with crescendo TIAs (two or more episodes in a week) should be treated as being at high risk of stroke, even though they may have an ABCD2 score of 3 or below.  The risk for stroke can be estimated from the ABCD2 score as follows: 2 day risk 7 day risk Score 1-3 (low) 1.0% 1.2% Score 4-5 (moderate) 4.1% 5.9% Score 6–7 (high) 8.1% 11.7% The Risk of future ischemic stroke after a TIA  overall annual risk is 3–4%,  over the next 7 days is 11%  over the following 5 years is 24–29%. Ref: emedicine.medscape.com Updated: Sep 11, 2017 https://emedicine.medscape.com/article/1910519-overview Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 7  13 Neurology A 77-year-old man presented after a single episode of unilateral weakness of the left arm that lasted for 2 hours. 170/100 mmHg. What is his chance of having a stroke in the first week? 11% Ref: www.mrcpuk.org/ Acute Medicine Specialty Certificate Examination/ sample questions Investigations (NICE guidelines. Last updated: March 2017 )  Most specific and sensitive for TIA  MRI is superior to CT in detecting the small ischemic lesions occurring after TIA and minor stroke.  Identifies ischemia earlier than CT (within 3–30 minutes after onset)  Non-contrast cranial CT (gold standard and most important initial imaging in stroke):  detects acute hemorrhage but cannot reliably identify early ischemia  CT scanning should only be used if MRI is contraindicated  Although the definition of TIA is "a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction," up to 50% of TIA show ischemic changes in imaging.  MRI findings of ischemia  T1: hypointense  T2: hyperintense  Time of image:  ABCD2 score ≥ 4  urgent brain imaging within 24 hours (preferably diffusion- weighted MRI)  the most appropriate next step  Admit for MRI neuroimaging, initiate anti-platelet therapy  ABCD2 score ≤ 4  brain imaging (preferably diffusion-weighted MRI) within 1 week  Duplex ultrasound of carotid stenosis  the most appropriate next step if bruits in the neck are heard upon auscultation.  If ultrasound is not available, a CTA or MRA may be used. Treatment  Antithrombotic therapy (2012 Royal College guideline)  clopidogrel is recommended first-line (as for patients who've had a stroke)  aspirin + dipyridamole should be given to patients who cannot tolerate clopidogrel 2016 Royal College guideline  Patients with a confirmed diagnosis of TIA should receive clopidogrel (300 mg loading dose and 75 mg daily thereafter) and high intensity statin therapy (e.g. atorvastatin 20-80 mg daily) started immediately. January 2013 exam: Which factor is most associated with an increased risk of going on to have a stroke in a patient presented with TIA? Duration of his TIA Stroke Etiology  35% - atherosclerosis of the extracranial vessels (carotid atheroma)  30% - cardiac and fat emboli, endocarditis  15% - lacunar  10% - parenchymal hemorrhage  10% - subarachnoid hemorrhage Presentation  Edema occurs 2-4 days post-infarct.  Watch for symptoms  decorticate (cortical lesion): flexion of arms  decerebrate (midbrain or lower lesion): extension of arms  cerebellar: ataxia, nystagmus, abnormal finger-nose and heel-shin Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 8  14 Neurology  Other stroke syndromes  lateral medullary infarct (Wallenburg syndrome)  loss of pain and temp on ipsilateral face and contralateral body, vestibulocerebellar impairment, Horner's syndrome Imaging  CT without contrast for acute presentation  the next best step in the management of stroke  to rule out hemorrhage  Contrast head CT is not used in the diagnosis of acute stroke.  if the CT is negative  MRI, specifically diffusion-weighted imaging and others, is the most widely used.  MR studies may show which brain regions are already infarcted and which are at risk of infarction if perfusion is not restored.  An acute ischemic stroke is diagnosed by diffusion weighted MRI or by using the clinical history (i.e. don't delay tPA just to get an MRI if there is strong clinical suspicion and no evidence of bleed). Management  If an ischemic stroke suspected clinically and CT is negative for evidence of a hemorrhagic stroke, the recommended treatment is to give IV tPA if the presentation is within 3-4.5 hours.  Of note, a contraindication to tPA is systolic BP > 185 or diastolic BP > 110 mm Hg.  For embolic disease and hypercoagulable states give warfarin or aspirin only once the hemorrhagic stroke has been ruled out. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 9  15 Neurology __________________________________________________________________ Stroke by anatomy Site of the lesion Associated effects Anterior cerebral artery Contralateral hemiparesis and sensory loss, lower extremity > upper Middle cerebral artery Contralateral hemiparesis and sensory loss, upper extremity > lower Contralateral homonymous hemianopia Aphasia (global aphasia) Posterior cerebral artery Contralateral homonymous hemianopia with macular sparing Visual agnosia Other possible findings:  Cortical blindness  Visual hallucinations  Thalamic syndrome, and  Claude's and Weber's syndromes. Weber's syndrome (branches of the posterior Ipsilateral CN III palsy cerebral artery that supply the midbrain) Contralateral weakness Or branches of the basilar artery Posterior inferior cerebellar artery Ipsilateral: facial pain and temperature loss (PICA)(lateral medullary syndrome, Contralateral: limb/torso pain and temperature loss. Wallenberg syndrome) Ataxia, nystagmus lesion to dorsolateral medulla Anterior inferior cerebellar artery (lateral Symptoms are similar to Wallenberg's (see above), but: pontine syndrome) Ipsilateral: facial paralysis and deafness Retinal/ophthalmic artery Amaurosis fugax Basilar artery 'Locked-in' syndrome __________________________________________________________________ Middle cerebral artery (MCA) occlusion For individuals aged up to 60 years who suffer an acute MCA territory ischaemic stroke complicated by massive cerebral oedema, surgical decompression by hemicraniectomy should be offered within 48 hours of stroke onset.  Divisions  Superior division  Occlusion of the superior division of the MCA results in:  contralateral hemiparesis that affects the face, hand and arm, but spares the leg  contralateral hemisensory deficit in the same distribution  no homonymous hemianopia  If the dominant hemisphere is involved, there is also expressive aphasia  Inferior division  Occlusion of the inferior division of the middle cerebral artery results in:  contralateral homonymous hemianopia  marked impairment of cortical sensory functions, such as graphaesthesia and stereognosis on the contralateral side of the body  disorders of spatial thought, including  lack of awareness that a deficit exists (anosognosia)  neglect of and failure to recognise the contralateral limbs  neglect of the contralateral side of external space Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 10  16 Neurology  dressing apraxia  constructional apraxia  Involvement of the dominant hemisphere also causes receptive aphasia  acute confusional state may occur if the non-dominant hemisphere is affected  Neurosurgery in treatment of MCA (decompressive hemicraniectomy)  Current clinical guidelines recommend that patients who are under 60 years of age with large cerebral infarctions arising in the MCA territory should be considered for decompressive hemicraniectomy.  Decompressive hemicraniectomy involves removing part of the skull in order to reduce intracranial pressure and should be carried out within 48 hours of the index event.  Eligibility is based on 1. Clinical and radiological evidence of a stroke affecting this territory, 2. Radiological evidence that more than 50% or 145 cm3 of the MCA territory is involved and 3. Being classified as having a moderate to severe stroke according to the National Institute of Health stroke scale. September 2010 exam: Right sided sensory loss affecting arms more than the legs + right sided homonymous hemianopia. What area is the stroke most likely to have affected? Middle cerebral artery __________________________________________________________________ Lacunar strokes Lacunar strokes is defined by one of:  Unilateral weakness (and/or sensory deficit) of face and arm, arm and leg or all three.  Pure sensory stroke.  Ataxic hemiparesis  The term 'lacune' refers to a small deep infarct resulting from occlusion of a penetrating branch  Lacunar infarcts occur in areas supplied by small perforating vessels and result from:  atherosclerosis  hypertension  diabetes  present with either isolated hemiparesis, hemisensory loss or hemiparesis with limb ataxia  strong association with hypertension  common sites include the basal ganglia, thalamus and internal capsule  The putamen is the commonest site for hypertensive intracerebral haemorrhage __________________________________________________________________ Lateral medullary syndrome  also known as Wallenberg's syndrome,  occurs following occlusion of the Posterior Inferior Cerebellar Artery  lesion to dorsolateral medulla  Features  Cerebellar features  ataxia  nystagmus  Brainstem features  ipsilateral: dysphagia, facial numbness, cranial nerve palsy e.g. Horner's  contralateral: limb sensory loss  Damage to:  vestibular nucleus  nystagmus and vomiting  inferior cerebellar peduncle  ipsilateral limb ataxia  spinothalamic tract  contralateral loss of pain and temperature sensation  IXth and Xth nerve nuclei  ipsilateral palatal, pharyngeal and vocal cord paralysis  nucleus and tract of the Vth nerve  ipsilateral loss of facial pain and temperature sensation  descending sympathetic fibres  ipsilateral Horner syndrome  Diagnosis Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 11  17 Neurology  MRI will be better able to visualise cerebellar infarction. September 2009 exam: Lateral medullary syndrome is caused by occlusion of which vessel? Posterior inferior cerebellar artery May 2012 exam: H/O unsteady feet, right-sided Horner's syndrome and horizontal nystagmus, sensory loss on the left side. Where is the lesion most likely to be? Posterior inferior cerebellar artery __________________________________________________________________ Pontine stroke Diplopia + hemiparesis + lower motor neurone facial nerve lesion  pontine stroke  Rapidly deteriorating level of consciousness, impaired extraocular movement and extensive sensorimotor deficits are clinical clues to pontine haemorrhage.  Decerebrate state is most likely a pontine lesion.  Millard-Gubler syndrome; a pontine lesion that produces:  ipsilateral Vlth and Vllth nerve palsy  contralateral hemiparesis Crossed neurological signs (ipsilateral motor and sensory cranial nerve signs and contralateral hemiplegia)  localise to the brainstem (midbrain, pons or medulla).  Pons  (ipsilateral abducens and facial nerves palsy, contralateral hemiplegia)  Midbrain  (ipsilateral oculomotor nerve palsy , contralateral hemiplegia) __________________________________________________________________ Weber's syndrome  ipsilateral III palsy  contralateral weakness __________________________________________________________________ Cerebellar haemorrhage  The most common symptoms are of severe nausea, vomiting and ataxia.  Headache may be severe.  Patients with cerebellar haemorrhage can rapidly become comatose within hours after the onset from herniation, because of its limited space in the posterior fossa. __________________________________________________________________ Hypoperfusion strokes  Hypoperfusion tends to cause brain injuries at 'watershed' areas that are border zones between the major cerebral arteries. __________________________________________________________________ Arteries aneurysms anterior communicating artery aneurysms  The most common aneurysm in circle of Willis  Most anterior artery communicating aneurysms are asymptomatic unless they rupture, and so they are usually found either incidentally or when a patient presents with SAH. Posterior communicating artery aneurysm will cause  compression of the third nerve, and therefore :  isolated ipsilateral painful third nerve palsy  Pupillary involvement (pupil dilation) from compression of the parasympathetic fibres that run on the outside of the third nerve  Other features of a third nerve palsy include ptosis, and a ‘down and out’ eye.  Cerebral aneurysms may be associated with polycystic kidney disease. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 12  18 Neurology __________________________________________________________________ Stroke: types  The Oxford Stroke Classification (also known as the Bamford Classification) classifies strokes based on the initial symptoms  The following criteria should be assessed: 1. unilateral hemiparesis and/or hemisensory loss of the face, arm & leg 2. homonymous hemianopia 3. higher cognitive dysfunction e.g. dysphasia  Total anterior circulation infarcts (TACI, c. 15%)  involves middle and anterior cerebral arteries  all 3 of the above criteria are present  Partial anterior circulation infarcts (PACI, c. 25%)  involves smaller arteries of anterior circulation e.g. upper or lower division of middle cerebral artery  2 of the above criteria are present  Lacunar infarcts (LACI, c. 25%)  involves perforating arteries around the internal capsule, thalamus and basal ganglia  presents with 1 of the following:  unilateral weakness (and/or sensory deficit) of face and arm, arm and leg or all three.  pure sensory stroke.  ataxic hemiparesis  Posterior circulation infarcts (POCI, c. 25%)  involves vertebrobasilar arteries  presents with 1 of the following:  cerebellar or brainstem syndromes  loss of consciousness  isolated homonymous hemianopia __________________________________________________________________ Stroke: assessment  FAST screening tool (Face/Arms/Speech/Time):  widely known by the general public following a publicity campaign.  It has a positive predictive value of 78%.  ROSIER score  useful for medical professionals.  It is validated tool recommended by the Royal College of Physicians.  Exclude hypoglycaemia first, then assess the following: Assessment Scoring Loss of consciousness or syncope - 1 point Seizure activity - 1 point New, acute onset of: asymmetric facial weakness + 1 point asymmetric arm weakness + 1 point asymmetric leg weakness + 1 point speech disturbance + 1 point visual field defect + 1 point  stroke is likely if > 0 Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 13  19 Neurology  Scores ad scales used in stroke score Used in “ABCD2” score predicts the risk of stroke following a transient ischaemic attack Barthel Index measures a person’s daily functioning, e.g ability to bath, feed “CHADS2-Vasc” assesses stroke risk in patients with non- valvular atrial fibrillation Modified Rankin Scale measures the degree of disability, after a stroke NIHSS Score (National is a tool used acutely to assess the degree Institute of Health Stroke of stroke-related neurologic deficit and Scale) hence determine appropriate treatment e.g. thrombolysis  Barthel index  used to assess disability following a stroke  The Barthel index correlates well with other prognostic scales.  It has very good concurrent and predictive validity.  It is very sensitive and it only takes 10 minutes to perform.  The most limitation of the Barthel index is floor and ceiling effects.  It basically means that a disabled person can score a maximum score of 100 and still not be independent.  It is poor at differentiating disability in patients who function at a higher level.  It also has floor effects as it may incorrectly score patients low who are initially bed bound following a stroke.  WHO International Classification of Functioning, Disability and Health (ICF)  The NICE guidelines on stroke suggest that we use terminology to describe the type of impairment in accordance with the WHO International Classification of Functioning, Disability and Health.  'impairment of body function'  Symptoms and signs like hemiparesis are classified as.  'activity limitation'  difficulties in executing certain activities, for example communication impairment in patients with aphasia following a stroke or the inability to pick up a cup in the affected hand.  'participation restriction'  problems in social roles - for example as a spouse or parent.  'pathology'  the diagnosis/disease. __________________________________________________________________ Stroke: management  Initial management  blood glucose, hydration, oxygen saturation and temperature should be maintained within normal limits  Blood pressure  should not be lowered in the acute phase unless there are complications e.g. Hypertensive encephalopathy.  Aspirin Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 14  20 Neurology  300mg orally or rectally should be given as soon as possible if a haemorrhagic stroke has been excluded  Thrombolysis  Thrombolysis should only be given if:  administered within 4.5 hours of onset of stroke symptoms  haemorrhage has been definitively excluded (i.e. Imaging has been performed)  Alteplase is currently recommended by NICE.  blood pressure should be reduced to below 185/110 mmHg before alteplase treatment  Patients treated with thrombolysis should be started on an antiplatelet agent after 24 hours once significant haemorrhage has been excluded.  Contraindications to thrombolysis: Absolute Relative  Previous intracranial haemorrhage  Concurrent anticoagulation  Seizure at onset of stroke (INR >1.7)  Intracranial neoplasm  Haemorrhagic diathesis  Suspected subarachnoid haemorrhage  Active diabetic haemorrhagic  Stroke or traumatic brain injury in preceding retinopathy 3 months  Suspected intracardiac  Gastrointestinal haemorrhage in preceding 3 thrombus weeks  Major surgery / trauma in  Lumbar puncture in preceding 7 days preceding 2 weeks  Active bleeding  Pregnancy  Oesophageal varices  Active pancreatitis.  Uncontrolled hypertension >200/120mmHg  patients with severe strokes only have an 8% likelihood of achieving clinically significant improvement with tPA alone.  Intra-arterial clot retrieval (Mechanical thrombectomy)  Advantages  safe and effective  Mechanical thrombolytic devices can remove a clot in a matter of minutes, whereas pharmaceutical thrombolytics, even those delivered intra-arterially, may take as long as 2 hours to dissolve a thrombus.  patients should undergo the procedure within 6 hours of symptom onset.  Indications  large vessel occlusion (usually in addition to IV thrombolytic therapy)  proximal MCA or  distal internal carotid artery or  basilar artery occlusion.  Patients who are ineligible for IV thrombolysis who present within the appropriate time-frame with large vessel occlusion.  Surgical treatment  decompressive hemicraniectomy  Indications  Patient with middle cerebral artery infarction who meet all of the criteria below: 1. Aged 60 years or under. 2. Clinical deficits suggestive of infarction in the territory of the middle cerebral artery, with a score on the National Institutes of Health Stroke Scale (NIHSS) of above 15. 3. Decrease in the level of consciousness to give a score of 1 or more on item 1a of the NIHSS. 4. Signs on CT of an infarct of at least 50% of the middle cerebral artery territory  Secondary prevention  clopidogrel is now recommended by NICE Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 15  21 Neurology  aspirin plus MR dipyridamole is now recommended after an ischaemic stroke only if clopidogrel is contraindicated or not tolerated, but treatment is no longer limited to 2 years' duration  MR dipyridamole alone is recommended after an ischaemic stroke only if aspirin or clopidogrel are contraindicated or not tolerated, again with no limit on duration of treatment  Aspirin  Start aspirin after excluding intracerebral haemorrhage by brain imaging  aspirin 300 mg orally if they are not dysphagic or if they are dysphagic  aspirin 300 mg rectally or by enteral tube.  aspirin 300 mg should be continued until 2 weeks after the onset of stroke, at which time definitive long-term antithrombotic treatment should be initiated.  Anticoagulation treatment for other comorbidities (e.g: atrial fibrillation):  should not be started until brain imaging has excluded haemorrhage,  usually after 14 days from the onset of an ischaemic stroke.  ischaemic stroke + atrial fibrillation  aspirin 300 mg for the first 2 weeks before considering anticoagulation treatment.  cerebral infarction in patient with prosthetic valves and who are at significant risk of haemorrhagic transformation, anticoagulation treatment should be stopped for 1 week and aspirin 300 mg substituted.  ischaemic stroke and symptomatic proximal DVT or PE  should receive anticoagulation treatment in preference to treatment with aspirin  haemorrhagic stroke and symptomatic DVT or PE  prevent further PE using either anticoagulation or a caval filter.  Statin treatment  Immediate initiation of statin is not recommended in acute stroke  Many physicians will delay treatment until after at least 48 hours due to the risk of haemorrhagic transformation  If already on statins should continue their statin  all patients who are diagnosed with stroke or TIA should be commenced on statin therapy irrespective of the cholesterol level.(passmedicine 2017 part 2)  Glycaemic management during the inpatient enteral feeding of stroke patients with diabetes:  The Joint British Diabetes Society 2012 guidelines recommend a target BM of between 6 and 12 mmol/l for hyperglycaemic patients on NG feed with insulin to be started when BM over 12 mmol/l.  The insulin regime of choice is a biphasic insulin such as humulin M3, with a mixture of intermediate and short acting insulin, prescribed twice daily, at the start and middle of the NG feed.  the optimal management of hyperglycaemia  Prescribe biphasic insulin twice daily  Patients with hyperglycaemia should never be prescribes PRN actrapid nor should the NG feed be stopped ________________________________________________________________________________ Spontaneous intracerebral haemorrhage Current management of spontaneous intracerebral haemorrhage (bmj.com 2017) http://svn.bmj.com/content/2/1/21  The most common locations of hypertensive ICH are the putamen, thalamus, subcortical white matter, pons and cerebellum  Common risk factors  HTN, (the most common risk factor)  age,  history of heavy alcohol,  methamphetamine or cocaine use,  education at less than a high school level and  genetic alleles associated with cerebral amyloid. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 16  22 Neurology  Classification by location  lobar versus non-lobar and supratentorial versus infratentorial.  Lobar ICH  commonly due to cerebral amyloid angiopathy (CAA).  Amyloid deposition in small-sized to medium-sized cortical perforators may lead to the rupture of these vessels,  Non-lobar ICH  commonly due to long-standing high blood pressure resulting in lipohyalinosis of small perforating arteries of the basal ganglia, thalamus, pons and cerebellum, leading to deep haemorrhages, often with extension into the ventricles.  Feature  ICH should be suspected in any patient with severe headache, vomiting, elevated systolic blood pressures or decreased level of consciousness.  Fever is common  Sustained fever after ICH is an independent prognostic factor for worse outcome.  Diagnosis  non-contrast head CT is highly sensitive and specific  Treatment  Stabilisation of airway, breathing and circulation (ABCs)  Intubation for airway protection is indicated in patient with GCS ≤8 or significant respiratory distress.  Patient with a decreased level of consciousness from intraventricular haemorrhage with hydrocephalus, mass effect or brainstem herniation should receive:  ventriculostomy,  hyperosmolar therapy with mannitol 0.5–1 g/kg or hypertonic saline (HTS) infusion.  In patients with an intracerebral haemorrhage, intervention to control the blood pressure is required only when the systolic BP exceeds 170 mmHg.  Intensive lowering of systolic blood pressure to 30 cbic centmetre) or symptomatic perihaematoma oedema, it may be beneficial to keep serum sodium level at 140–150 mEq/L for 7–10 days to minimise oedema expansion and mass effect.  Mannitol and hypertonic saline (HTS) can be used emergently for worsening cerebral oedema, elevated intracranial pressure (ICP) or pending herniation.  Ventriculostomy is indicated for patients with severe intraventricular haemorrhage, hydrocephalus or elevated ICP.  Reversal of coagulopathies  12–20% of patients presenting with ICH are taking oral anticoagulants.  For all patients taking vitamin K antagonists (eg, warfarin)  for patients with INR ≥1.4:  vitamin K 10 mg and 3-factor or 4-factor prothrombin complex concentrates (PCCs) Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 17  23 Neurology  PCC is an inactivated concentrate of factors II, IX and X, with variable amounts of factor VII.  Variation in factor VII concentrations in PCC has led to their classification as either 3- or 4-factor.  PCC is preferred over FFP  Recombinant Factor VIIa (rFVIIa) has been associated with relatively high thrombosis rates and should only be considered in patients who will not accept blood products (eg, Jehovah's witness).  Direct thrombin inhibitors (DTIs; eg, dabigatran, argatroban and bivalirudin)  reversal of coagulopathy is indicated if patient presents within 3–5 half-lives (or beyond in patient with renal insufficiency).  haemorrhage associated with dabigatran  Idarucizumab (5 g intravenous divided into two doses)  If idarucizumab is not available, or if the haemorrhage is associated with a DTI other than dabigatran, PCC is recommended.  Haemodialysis can also be considered in patients with dabigatran-associated ICH and renal insufficiency, especially if continued haemorrhage despite first-line therapies.  For patients taking Factor Xa inhibitors (eg, rivaroxaban, apixaban and edoxaban):  PCC is recommended if the haemorrhage occurred within 3–5 half-lives of drug exposure (or in context of liver failure).  If presenting within 2 hours of drug exposure, activated charcoal can be administrated to prevent further drug absorption.  Laboratory testing is unlikely to be helpful in guiding treatment; therefore, reversal should be guided by bleeding (major or intracranial) instead.  low-molecular-weight heparin (low molecular weight heparin (LMWH); eg, enoxaparin, dalteparin, nadroparin and tinzaparin)   protamine should be administered.  For thrombolytic (eg, recombinant tissue plasminogen activator (rtPA)) reversal: st  1 line  cryoprecipitate administration.  2nd line (If cryoprecipitate is contraindicated or unavailable),  tranexamic acid ( anti-fibrinolytic agent)  For patients taking antiplatelet agents (eg, aspirin, clopidogrel and abciximab):  platelet transfusion is not recommended routinely, regardless of antiplatelet agent, platelet function testing, haemorrhage volume or neurological examination.  Platelet transfusion seems inferior to standard care for patients taking antiplatelet therapy before ICH  Platelet transfusion should be considered for patients with aspirin- or adenosine diphosphate receptor (ADP) inhibitor-associated ICH who will undergo a neurosurgical procedure.  Platelet function testing prior to platelet transfusion should be performed if possible and timely results available. If platelet function is within normal limits or patient has documented antiplatelet resistance, platelet transfusion should be avoided.  Management of intraventricular haemorrhage (IVH) and hydrocephalus  (IVH) occurs in up to 45% of patients with ICH.  External ventricular drain (EVD) placement should be considered in:  any patient with GCS ≤ 8,  significant IVH,  hydrocephalus or  evidence of transtentorial herniation  Elevated ICP (>20 mm Hg) should be treated with hyperosmolar therapy (HTS and/or mannitol), cerebrospinal fluid drainage or sedation, though none of these therapies has been shown to improve outcomes  Surgical intervention  no benefit for early haematoma evacuation in patients with supratentorial ICH Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 18  24 Neurology  Unlike supratentorial ICH, cerebellar ICH is considered a neurosurgical emergency and evacuation is recommended per current guidelines given the high morbidity from rapid development of brainstem compression  Surgical indications include:  haematoma size >3 cm in diameter,  brainstem compression or  hydrocephalus.  Management of peri-haematoma oedema (PHE)  (PHE) develops within the first few days after ICH and may cause elevated ICP, mass effect, midline shift and brain herniation  asymptomatic PHE require no specific treatment except maintaining a normal sodium goal.  symptomatic cerebral oedema and elevated ICP  mannitol and hypertonic saline (HTS) are the first-line  Mannitol is an osmotic diuretic. It increases water excretion by the kidneys and reduces cerebral oedema and ICP.  HTS increases plasma osmolarity and the flow of excess water from cerebral tissue to the blood via the osmotic gradient.  HTS vs mannitol:  A meta-analysis performed in 2011 showed that HTS is slightly more effective than mannitol for the treatment of elevated ICP.  A recent analysis of the INTERACT2 data showed that mannitol seems safe, but might not improve outcome in patients with acute ICH  According to patient's medical history:  patients with congestive heart failure should receive a bolus of mannitol or 23.4% of HTS,  whereas continuous infusion of 3% of HTS can be used for patients with dehydration or decreased urine output.  Patients with DVT or PE + ICH:  consider anticoagulation depending on stability of the haematoma, cause of haemorrhage and time since presentation.  If systemic anticoagulation is contraindicated, inferior vena cava filter placement should be considered  Prophylactic management  prophylaxis of venous thromboembolism (VTE):  risk of (DVT) is 1–5%.  Start mechanical VTE prophylaxis at the time of admission  preferably with intermittent pneumatic compression (IPC) devices  cuffs around the legs that fill with air and squeeze legs  blood flow through the leg veins  prevent blood clots.  If (IPC) devices are unavailable, graduated compression stockings (GCS) can be utilised.  Early aggressive comprehensive care may improve survival and functional recovery.  Prophylactic doses of subcutaneous unfractionated heparin or LMWH should be started in patients with stable haematomas within 48 hours of admission.  Mechanical VTE prophylaxis should be continued after initiation of pharmacological prophylaxis.  There is no benefit for seizure prophylaxis or aggressive management of fever or hyperglycaemia. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 19  25 Neurology Intracerebral haemorrhage in association with anticoagulants (royal college guidelines 2016): intracerebral haemorrhage in association with reversed with vitamin K antagonist treatment combination of prothrombin complex concentrate and intravenous vitamin K. dabigatran idarucizumab factor Xa inhibitor prothrombin complex concentrate The 2016 RCP stroke guidelines state: Patients with primary intracerebral haemorrhage who present within 6 hours of onset with a systolic blood pressure above 150mmHg should be treated urgently using a locally agreed protocol for blood pressure lowering to a systolic blood pressure of 140 mmHg for at least 7 days, unless:  the Glasgow Coma Scale score is 5 or less  the haematoma is very large and death is expected  a structural cause for the haematoma is identified  immediate surgery to evacuate the haematoma is planned. January 2013 exam: Which medications should be given following an ischaemic stroke (i.e. after 14 days)? Clopidogrel + statin Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 20  26 Neurology September 2009 exam: A 62-year-old man admitted 5 hours after left hemiplegia. ECG confirms atrial fibrillation. A CT head is normal. What is the most appropriate initial management? Aspirin (He is outside the thrombolysis window so alteplase is not an option. anticoagulation should be commenced 14 days after an ischaemic stroke.) ________________________________________________________________________________ Paradoxical embolisation  For a right-sided thrombus (e.g. DVT) to cause a left-sided embolism (e.g. stroke) it must obviously pass from the right-to-left side of the heart.  The following cardiac lesions may cause such events  patent foramen ovale  present in around 20% of the population  Transoesophageal echocardiography (TOE) is the investigation of choice to investigate for a patent foramen ovale,  transthoracic echocardiography with contrast may be an alternative.  TOE offers better views of the anatomical area.  atrial septal defect - a much less common cause ________________________________________________________________________________ Cerebral venous thrombosis (CVT) Patients with a hypercoagulable state (e.g pregnancy) and papilloedema with neurological signs should be investigated for cerebral venous thrombosis. Basics  Structure  reflections in dura matter where meningeal and periosteal layers split  Function  return blood from cerebral veins to internal jugular vein  veins contains NO valves Epidemiology  more common in young women  Sex: ♀ > ♂, 3:1  Age of onset: ≤ 40 years Pathophysiology  The underlying problem is a thrombosis and the petechial haemorrhages are caused by venous outflow blockage.  Thrombogenesis occurs in the cerebral venous system, cerebral drainage intracranial pressure clinical features (see below)  Additionally, thrombus formation congestion within the venous system of the brain blood stasis oxygenated blood in brain tissue cerebral edema and/or infarcts/stroke. Types  The dural sinuses are grouped into:  sagittal,  lateral (including the transverse, sigmoid, and petrosal sinuses), and  cavernous sinuses.  Because of its complex neurovascular anatomic relationship, it is the most important of any intracranial septic thrombosis.  50% of patients have isolated sagittal sinus thromboses  the remainder have coexistent lateral sinus thromboses and cavernous sinus thrombosis Risk factors and etiology  local infection  Staphylococcus aureus is the most common  sinusitis  Frontal sinuses are the most common source of infection  local infection midface infection  most commonly a furuncle  diabetes mellitus  hypercoagulable states: Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 21  27 Neurology  pregnancy, post-partum period ,  It typically presents with headache, seizures and focal neurological deficit two to three weeks postpartum (but is also seen earlier.  Malignancy  clotting disorders (e.g., factor V Leiden, protein C and S deficiencies, antiphospholipid syndrome)  polycythemia  intracranial hypotension  lumbar puncture  Minor head trauma  medications  Oral contraceptive pill, including the third-generation formulations  Corticosteroids  Epsilon-aminocaproic acid  Thalidomide  Tamoxifen  Erythropoietin  Phytoestrogens  L-asparaginase  Heparin - Heparin therapy has been reported to produce thrombotic thrombocytopenia with associated venous sinus thrombosis Features  Raised intracranial pressure (ICP):  headache  The most common presenting symptom  nausea & vomiting  Vomiting in the morning is characteristic of raised ICP as it follows a period of lying flat.  Bending over, coughing or straining causes a transient increase in already raised ICP ↑optic nerve compression  visual disturbance.  Papilloedema  Cranial nerve symptoms  (e.g., diplopia, tinnitus, unilateral deafness, facial palsy)  Cranial nerves III, IV and VI palsies  Ocular chemosis  Proptosis  Seizures  Focal or generalized seizures are frequent, occurring in up to 40% of patients.  rare cause of stroke, Investigations  If CVT is suspected, D-dimer levels and imaging studies are first steps of diagnosis  D-dimers: > 500 μg/L  Imaging:  CT/MRI (with or without venography): tests of choice to confirm the diagnosis  Plain CT/MRI help detect only edema and/or infarcts, but the thrombus itself can be visualized by means of venography.  CT  Hypodense structures indicate ischemic event  Thrombus can appear as a hyperdense vein or sinus  CT venography shows a filling defect in a vein or sinus  MRI  Thrombus is isointense on T1 and hypointense on T2 early in the disease  Cerebral edema can be identified  MR venography demonstrates a lack of flow  Evaluation for possible causes  ESR and antibody studies Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 22  28 Neurology  CBC, CRP  Tests for clotting disorders (e.g., Leiden factor V mutation)  Thrombophilia screen should be performed. Treatment of cerebral venous thrombosis  If primary anticoagulants (full-dose heparin then warfarin).  Secondary thrombosis (usually secondary to infection) should be treated or drained if possible.  Dexamethasone can be used to reduce cerebral oedema.  Surgical therapy  Indications  Progressive neurologic worsening (despite adequate anticoagulation)  Acute rise in intracranial pressure  Impending herniation  Surgical options  Blood clot removal  Vessel recanalization  Shunt placement Sagittal sinus thrombosis  the most frequently affected sinus  Superior sagittal sinus thrombosis (SSST) is the most common type of dural venous sinus thrombosis  Features  Anterior occlusion is usually asymptomatic,  posterior occlusion can present with:  raised intracranial pressure (headache, vomiting), and papilloedema  involvement of the upper hemispheres (paraplegia).  may present with seizures and hemiplegia  disorder of the oculomotor nerve by affecting the oculomotor (Edinger-Westphal) nuclei.  parasagittal biparietal or bifrontal haemorrhagic infarctions are sometimes seen  The territory of the affected sinus usually shows congestive oedema, which can progress to haemorrhagic venous infarction.  on contrast CT empty delta sign (is a specific to the superior sagittal sinus) Empty delta sign  superior sagittal sinus thrombosis  CT with contrast demonstating a superior sagittal sinus thrombosis showing the typical empty delta sign.  Look at the 'bottom' of the scan for the triangular shaped dural sinus.  This should normally be white due to it being filled with contrast.  The empty delta sign occurs when the thrombus fails to enhance within the dural sinus and is outlined by enhanced collateral channels in the falx.  This sign is seen in only about 25%-30% of cases but is highly diagnostic for sagittal sinus thrombosis Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 23  29 Neurology Cavernous sinus thrombosis (CST) Cavernous sinus contents Structures passes through the cavernous sinus:  internal carotid artery with its surrounding sympathetic plexus  third, fourth, and sixth cranial nerves are attached to the lateral wall of the sinus.  Ophthalmic (V1) and maxillary (V2) divisions of the fifth cranial nerve are embedded in the wall  The mandibular branch of the trigeminal nerve (V3) does not travel in the cavernous sinus and would therefore not be affected.  V3 innervates the lower face. (NO lower face symptoms) Other features of cavernous sinus syndrome  peri-orbital oedema (Chemosis, oedema and cyanosis of the upper face occur due to obstruction of the ophthalmic vein)  Eye swelling begins as a unilateral process and spreads to the other eye within 24- 48 hours via the intercavernous sinuses. This is pathognomonic for CST.  Periorbital edema may be the earliest physical finding.  ophthalmoplegia:  6th nerve damage typically occurs before 3rd & 4th  Lateral gaze palsy (patient cannot abduct eye) (isolated cranial nerve VI) is usually seen first  since CN VI lies freely within the sinus in contrast to CN III and IV, which lie within the lateral walls of the sinus.  Ptosis, mydriasis, and eye muscle weakness from cranial nerve III dysfunction  Patients typically have double vision on looking upward  trigeminal nerve involvement may lead to hyperaesthesia of upper face and eye pain  central retinal vein thrombosis  Signs of increased intraocular pressure (IOP) may be observed.  Pupillary responses are sluggish.  Decreased visual acuity is common Which group of nerves run through the cavernous sinus?  III, IV, (V-1, V-2), and VI September 2012 exam: Left-sided eye pain & diplopia for the past 2 days + 6th & 3rd cranial nerve palsy on the left side + hyperaesthesia of the upper face on the left side. Where is the likely lesion? Cavernous sinus superior orbital fissure syndrome  is similar to the cavernous sinus syndrome except for the presence of proptosis. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 24  30 Neurology Lateral sinus thrombosis  6th and 7th cranial nerve palsies ________________________________________________________________________________ Lesions at the jugular foramen Causes of jugular foramen syndromes  Nasopharyngeal carcinoma is the commonest cause.  Other are  neurofibromas, metastatic tumours, jugular vein thrombosis, Paget’s disease of the bone, and basal skull fractures. Affected CN  9,10,11  CN IX (Glossopharyngeal nerve) & CN X (Vagus nerve)  palatal weakness and swallowing difficulties , Laryngeal muscle paralysis would result in bovine cough and husky voice.  CN XI (Accesory nerve)  shoulder and sternocleidomastoid weakness ________________________________________________________________________________ Cervical vascular dissection Stroke provoked by minimal trauma (e.g: exercise) is likely due to Cervical vascular dissection until proven otherwise  Mechanism of ischaemia  Most ischaemic symptoms (85-95%) of cases are caused by emboli from the site of the dissection.  (5-15%) due to vessel narrowing (subintimal tears  intramural haematomas  protrude inward and narrow the vessel lumen)  Feature  sudden-onset weakness and numbness provoked by exercise  When an ischaemic event occurs in the context of exercise, the possibility of a Valsalva manoeuvre precipitating embolism from a patent foramen ovale should also be considered.However, an arterial dissection should be considered most likely until proven otherwise  Horner's sign may be present  two-thirds of patients have head or neck pain, the remainder present painlessly  Investigation  (magnetic resonance angiography) __________________________________________________________________ Carotid artery stenosis  Epidemiology  Carotid artery stenosis causes 10% to 15% of all ischaemic strokes.  the annual risk of stroke in patients with asymptomatic carotid disease is between 1% and 2%  Pathophysiology  Atherosclerotic plaque in the cervical carotid artery is the most common cause.  Plaque disruption and athero-embolisation into the intracranial circulation is the most common mechanism for stroke.  The most common site of carotid Atherosclerosis:  usually at the fork where the common carotid artery divides into the internal and external carotid artery.  Features Carotid artery atherosclerosis is an important cause of ipsilateral amaurosis fugax.  The majority of carotid artery stenosis are asymptomatic.  cervical bruit  plaques rupture  embolism to :  intracranial arteries  (TIA or stroke) or  retinal arteries  (amaurosis fugax or retinal strokes).  Diagnosis  Duplex ultrasonography is the preferred mode of diagnosis;  sensitivity of 99%, specificity of 86%  stepwise diagnostic work-up:  carotid duplex for screening purposes. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 25  31 Neurology If the stenosis is less than 50%,  no further imaging is needed. If the stenosis > 50%, CTA or MRA should be considered for more detailed plaque characterization.  CT or magnetic resonance angiography helps to define the anatomy if intervention is indicated.  computed tomography angiography (CTA)  sensitivity is 85% and specificity 93%  requires exposure to ionising radiation, and the iodinated contrast is a hazard in patients with renal insufficiency.  faster and less expensive than MRA.  less susceptible than (MRA) to overestimate the stenosis  magnetic resonance angiography (MRA)  Less commonly performed than CTA  sensitivity 88% and specificity 84%  has a tendency to overestimate stenosis severity.  does not require ionising radiation.  NICE guidelines state that a patient with a TIA should receive a CT/MRI head and carotid duplex within a week.  cervical angiography  The definitive test for identifying and quantifying the degree of stenosis in the carotid artery  however, it is infrequently ordered as it is invasive (requiring catheterisation of the aortic arch and carotid artery) and carries a risk of atheroembolic stroke.  Generally ordered when non-invasive tests show a suspicion of a string sign (i.e., ≥95% stenosis).  Management  Initial management  antiplatelet therapy, and risk factor modification.  endarterectomy  Indications  if carotid stenosis > 70% according ECST criteria (European Carotid Surgery Trial' Collaborative Group)  or > 50% according to NASCET (North American Symptomatic Carotid Endarterectomy Trial) criteria. 2016 Royal College guideline recommend that : The degree of carotid artery stenosis should be reported using the (NASCET) method.  If carotid endarterectomy is deemed necessary then surgery should be performed within two weeks. ("urgent" endarterectomy within 2 weeks)  It reduces the risk of disabling stroke or death by 48% in a person with severe symptomatic carotid stenosis (>70%) who has had a TIA.  The peri-operative risk of disabling stroke or death is approximately 3%.  The benefit of endarterectomy is prevention of future stroke.  Surgery will be appropriate if there is a TIA or resolving stroke.  with dense strokes, if there is no recovery, the benefits are greatly reduced due to end-organ damage.  Contraindications:  100% carotid stenosis  usually requires a bypass procedure, as risk of endarterectomy outweighs benefit.  previous stroke with persistent neurological symptoms  Carotid stenting  used as an alternative to endarterectomy.  less invasive revascularisation strategy, and uses an embolic protection device.  There seems to be a similar early risk of death or stroke, and similar long-term benefits.  Indications  Restenosis. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 26  32 Neurology  Previous radiotherapy to the neck may make endarterectomy difficult, and stenting may be preferred.  Revascularisation would have the risk of reperfusion haemorrhage.  Risk is higher in elderly patients, possibly due to vascular tortuosity and calcification. Question left-sided hemiparesis of more than 8 hours’ duration. carotid ultrasound scan, shows 80% stenosis of the left carotid artery, 50% stenosis of the right carotid artery. What is the most appropriate treatment for long-term stroke prevention?  Clopidogrel  endarterectomy is not recommended in:  significant stenosis but asymptomatic side (left carotid in this case)  symptomatic side but there is less than 70% (right carotid in his case). Carotid artery stenosis management  Symptomatic (TIA, stroke, and amaurosis fugax)  ipsilateral carotid stenosis ≥ 50% (NASCET criteria)  carotid endarterectomy + antiplatelet therapy and cardiovascular risk reduction  ipsilateral carotid stenosis < 50%  antiplatelet therapy and cardiovascular risk reduction  Asymptomatic  asymptomatic carotid stenosis lower quadrant defect = inferior chiasmal compression, commonly a pituitary tumour Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 34  40 Neurology  lower quadrant defect > upper quadrant defect = superior chiasmal compression, commonly a craniopharyngioma Bilateral internal carotid artery displacement can cause binasal incongruous hemianopia if the optic nerves are compressed. September 2012 exam: What sort of visual field defect is expected following an operation to remove a meningioma in left temporal lobe? Right superior homonymous quadrantanopia January 2009 exam: In a left congruous homonymous hemianopia. Where is the lesion most likely to be? Right occipital cortex ____________________________________________________________________________ Cortical blindness  The visual cortex is located in the occipital lobes, receiving its blood supply from the posterior cerebral arteries.  The area for macular vision is in a small area adjacent to the calcarine sulcus.  Bilateral occlusion or infarction of the vessels supplying this area results in cortical blindness:  the visual pathways as far as the cortex are normal and as a result pupillary reactions and fundoscopy are normal.  Patients with cortical blindness frequently have visual hallucinations and occasionally deny that they are blind. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 35  41 Neurology ____________________________________________________________________________ Drop attacks  Drop attacks describes the sudden falling to one's knees without loss of consciousness and without warning. Recovery is immediate.  Often the attacks spontaneously stop after a year or two.  The aetiology of drop attacks is uncertain.  Over 90% of drop attacks occur in women although men can develop the problem.  The average age of onset is between 45 and 55  textbooks suggest that vertebrobasilar ischaemia is the cause Features  sudden fall to the ground while standing or walking  Patients with functional drop attacks normally can’t remember the fall itself but are aware of the impact on the ground (or within seconds of falling). This is different to a mechanical fall when people often do remember the fall (often in detail). Its also different to a dissociative attack (non- epileptic attack) where there is an actual ‘blackout’.  Unlike an epileptic seizure or a faint, people with drop attacks can usually get up again quite quickly  Injury is a common consequence ____________________________________________________________________________ Klüver–Bucy syndrome  Klüver–Bucy syndrome is a syndrome resulting from bilateral lesions of the medial temporal lobe (including amygdaloid nucleus).  Herpes simplex virus-1 can cause bilateral amygdala lesions leading to Klüver–Bucy syndrome.  may present with  compulsive eating,  hypersexuality,  insertion of inappropriate objects in the mouth (hyperorality),  visual agnosia, and docility. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 36  42 Neurology ________________________________________________________________________________ Cranial nerves ________________________________________________________________________________ Brain stem (Mid brain, Pons, Medulla Oblongata) lesions are typically characterized by ipsilateral cranial nerve involvement and contralateral body involvement.  Lesions of the cerebellopontine angle causes compression of cranial nerves V (trigeminal), VII (facial) and VIII (vestibulocochlear).  The cavernous sinus syndrome consists of variable involvement of  Oculomotor (III)  Trochlear (IV)  Abducens (VI)  Trigeminal (ophthalmic and maxillary division) (V) and  Oculo-sympathetic nerves.  The superior orbital fissure syndrome is similar to the cavernous sinus syndrome except for the presence of proptosis.  petrous apex lesion  features  abducens nerve palsy  horizontal diplopia  ipsilateral Facial pain or sensory disturbance (numbness) in the trigeminal nerve distribution  occurs secondary to involvement of the trigeminal nerve at the Meckel cave.  causes  meningioma or nasopharyngeal carcinoma of the petrous apex.  The most common cause now  petrous osteitis (Gradenigo syndrome) Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 37  43 Neurology  In the pre-antibiotic era __________________________________________________________________________________ Optic nerve  The optic and olfactory nerves lie entirely within the supra-tentorial fossa, unlike the rest of the cranial nerves.  The optic nerve is part of the central nervous system, hence its myelin sheaths are derived from oligodendrocytes, not Schwann cells.  Accordingly, diseases of the peripheral nervous system and radiculopathies don’t target the optic nerve.  The physiological blind spot results from absence of photoreceptors in the area of the retina where the optic nerve leaves the eye.  It leaves the eye through the optic canal. It forms the afferent pathway of the direct and consensual pupillary reflexes. __________________________________________________________________________________ Oculomotor Third (III) nerve palsy Features  divergent squint - affected eye deviated 'down and out'.  ptosis  dilated pupil (sometimes called a 'surgical' third nerve palsy)  Unreactive pupil to light Causes  diabetes mellitus  vasculitis e.g. temporal arteritis, SLE  false localizing sign due to uncal herniation through tentorium if raised ICP  posterior communicating artery aneurysm (pupil dilated)  cavernous sinus thrombosis  Weber's syndrome: ipsilateral third nerve palsy with contralateral hemiplegia -caused by midbrain strokes  other possible causes: amyloid, multiple sclerosis Ipsilateral 3rd CN palsy + contralateral hemiplegia  Weber's syndrome Ipsilateral 3rd CN palsy + contralateral hemiataxia  Benedikt syndrome Ipsilateral 3rd CN palsy + ipsilateral hemiparesis + Contralateral homonymous hemianopsia  Uncal herniation __________________________________________________________________________________ Fourth nerve (IVth) palsy Overview  supplies superior oblique (depresses eye, moves inward)  Head trauma (including minor head injuries) can result in a trochlear nerve palsy as it is compressed against the tentorial edge or along another part of the pathway.  The fourth cranial nerve palsy  superior oblique palsy vertical diplopia  (eg: missing steps when walking down the stairs, bumping head when trying to get out of a car) Features  vertical diplopia  classically noticed when reading book or going down stairs  The trochlear nerve would lead to nystagmus on looking down and out. ________________________________________________________________________________ Trigeminal neuralgia  Sensation over the face is supplied by the trigeminal nerve  Trigeminal neuralgia is a pain syndrome characterised by severe unilateral pain. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 38  44 Neurology  Causes  idiopathic (The vast majority)  compression of the trigeminal roots by tumours or vascular problems  The International Headache Society defines trigeminal neuralgia as:  unilateral disorder characterised by brief electric shock-like pains, abrupt in onset and termination, limited to one or more divisions of the trigeminal nerve  the pain is commonly evoked by light touch, including washing, shaving, smoking, talking, and brushing the teeth (trigger factors), and frequently occurs spontaneously  small areas in the nasolabial fold or chin may be particularly susceptible to the precipitation of pain (trigger areas)  the pains usually remit for variable periods  Management  carbamazepine is first-line  failure to respond to treatment or atypical features (e.g. < 50 years old) should prompt referral to neurology January 2015 exam: History of electric shock like pains on the right side of the face. around 10-20 episodes a day which, each lasting for around 30-60 seconds. What is the most suitable first-line management? Carbamazepine What is the nerve supply to the angle of the jaw? The angle of the jaw is supplied by nerve roots C2/C3 and not the trigeminal nerve. In patients with non-organic sensory loss, that loss usually extends to the edge of the jaw. ________________________________________________________________________________ abducens (VIth) nerve palsy  The VIth nerve is motor to the lateral rectus muscle.  It is responsible for abduction of the ipsilateral eye.  In the neutral position the affected eye is deviated medially due to unopposed action of the medial rectus.  In patients with diplopia the 'cover test' can be used to determine the eye that has the problem.  On covering the affected eye the outermost image disappears.  Eg : diplopia on right horizontal gaze , improved on covering the right eye  the right abducens is affected  After finding a VIth nerve palsy the cause should always be looked for, it is not a diagnosis in itself.  Due to the long course and anatomy of the VIth nerve it can be damaged in any condition causing raised intracranial pressure. It can therefore be a 'false localising sign'. Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 39  45 Neurology __________________________________________________________________________________ Facial (VII) nerve Facial nerve branches (mnemonic) (superior to inferior) as they exit the anterior border of the parotid gland: To Zanzibar By Motor Car 1. T: temporal 2. Z: zygomatic 3. B: buccal 4. M: mandibular 5. C: cervical Facial Palsy + convergent squint lesion in Pons as VI th is encircled by VII th Supply - 'face, ear, taste, tear'  face: muscles of facial expression  ear: nerve to stapedius (Hyperacusis is due to paralysis of stapedius)  taste: supplies anterior two-thirds of tongue  tear: parasympathetic fibres to lacrimal glands, also salivary glands  Orbicularis oculi is affected causing inability to blink/close eyelids. Causes of bilateral facial nerve palsy 1. sarcoidosis 2. Guillain-Barre syndrome 3. polio, 4. Lyme disease Causes of unilateral facial nerve palsy - as above plus Lower motor neuron Upper motor neuron  Bell's palsy  stroke  Ramsay-Hunt syndrome (due to herpes zoster)  acoustic neuroma  parotid tumours  HIV  multiple sclerosis*  may also cause an UMN palsy  diabetes mellitus LMN vs. UMN  upper motor neuron lesion 'spares' upper face i.e. forehead  lower motor neuron lesion affects all facial muscles Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 40  46 Neurology ___________________________________________________________________ Bell's palsy Definition  acute, unilateral, idiopathic, facial nerve paralysis. Causes  unknown  although the role of the herpes simplex virus has been investigated previously. Epidemiology  The peak incidence is 20-40 years  more common in pregnant women. Features  lower motor neuron facial nerve palsy - forehead affected  other features  post-auricular pain (may precede paralysis),  altered taste,  dry eyes,  hyperacusis (seen in around a third of patients) Management  prednisolone 1mg/kg for 10 days should be prescribed for patients within 72 hours of onset of Bell's palsy.  Adding in aciclovir gives no additional benefit  eye care is important - prescription of artificial tears and eye lubricants should be considered Prognosis  if untreated around 15% of patients have permanent moderate to severe weakness January 2012 exam: Which features would be most consistent with a diagnosis of Bell's palsy? Hyperacusis May 2010 exam: What is the current evidenced base approach to the management of Bell's palsy? Prednisolone ________________________________________________________________________________ Ramsay Hunt syndrome Aetiology  Ramsay Hunt syndrome (herpes zoster oticus) is caused by the reactivation of the varicella zoster virus in the geniculate ganglion of the seventh cranial nerve. Features  auricular pain is often the first feature  facial nerve palsy  vesicular rash around the ear  other features include vertigo and tinnitus Management  oral aciclovir and corticosteroids are usually given ________________________________________________________________________________ Acoustic neuroma  Acoustic neuromas (more correctly called vestibular schwannomas)  account for 5% of intracranial tumours and 90 % of cerebellopontine angle  Features can be predicted by the affected cranial nerves  cranial nerve V: absent corneal reflex  cranial nerve VII: facial palsy  cranial nerve VIII: hearing loss, vertigo, tinnitus  Bilateral acoustic neuromas are seen in neurofibromatosis type 2  MRI of the cerebellopontine angle is the investigation of choice Notes & Notes for MRCP By Dr. Yousif Abdallah Hamad 41  47 Neurology Other notes  The lacrimal gland is supplied by the facial nerve.  The glossopharyngeal nerve supplies the parotid salivary gland controlling salivary secretions.  The trochlear nerve supplies the superior oblique muscle.  The oculomotor nerve innervates the superior rectus.  The vagus nerve supplies the palatal muscles. ____________________________________________________________ Holmes tremor Holmes tremor  lesion in the red nucleus  Holmes tremor is caused by a lesion in the red nucleus.  This is most commonly due to a previous stroke of this area.  It is classically an irregular low frequency tremor which is a combination of resting, postural and action tremor.  It may also arise from any underlying structural disorders including multiple sclerosis, tumors, haemorrhage, trauma, neuroleptic agents, radiation.  Treatments include:  medical therapy such as levodopa  however thalamotomy or chronic thalamic stimulation have also shown to play a role in managing this condition. Movement disorders Movement disorders in order of least speed to fastest (DACB)  Dystonia - fixated position  Athetosis - Snake-like writhing (slow)  Choreiform - Like a dance choreographer  Ballistic/Ballismus/Hemiballismus - Fast flinging movements, can injure themselves or others 'like a ballistic missile' (memorisation method) Chorea  Chorea describes involuntary, rapid, jerky movements which often move from one part of the body to another ('dance-like').  Slower, sinuous movement of the limbs is termed athetosis.  Chorea is caused by damage to the basal ganglia, especially the caudate nucleus. Causes of chorea  Inherited causes such as:  Huntington's chorea  Wilson's disease  ataxic telangiectasia  Ac