Neuroma & Cranial Nerve Function

Block 2 Practice Questions

Acoustic Neuroma and Cranial Nerve Affectation

• A sixty-four-year old man diagnosed with an acoustic neuroma (tumor of the VIIIth cranial nerve).
• The VIIIth cranial nerve is also known as the vestibulocochlear nerve.
• The VIIth cranial nerve, also known as the facial nerve, passes through the internal auditory meatus.
• An acoustic neuroma typically affects the vestibulocochlear nerve (VIII) as it enters the temporal bone.
• The facial nerve (VII) passes through the internal auditory meatus before traveling to the facial muscles.
• A tumor affecting the VIIIth cranial nerve at the internal auditory meatus can compress the facial nerve (VII).
• The abducens nerve (VI) travels through the superior orbital fissure.
• The glossopharyngeal nerve (IX) passes through the jugular foramen.
• The trigeminal nerve (V) passes through the trigeminal (V) foramen.

Auriculotemporal Nerve and Parotid Gland Function

• Loss of sensation from the temporal region and loss of secretory function of the parotid gland would be caused by interruption of the auriculotemporal nerve.
• The auriculotemporal nerve is a branch of the mandibular division of the trigeminal nerve (CN V3).
• The auriculotemporal nerve carries both sensory information from the temporal region and parasympathetic fibers involved in the secretory function of the parotid gland.
• The auriculotemporal nerve carries parasympathetic fibers from the glossopharyngeal nerve (CN IX) via the otic ganglion to stimulate secretion from the parotid gland.
• Interruption of the auriculotemporal nerve would result in a loss of the parotid gland's secretory function (reduced saliva production).
• The chorda tympani is a branch of the facial nerve (CN VII) that carries taste sensation from the anterior two-thirds of the tongue and parasympathetic fibers to the submandibular and sublingual glands, but does not affect the temporal region or the parotid gland.
• Deep temporal, posterior nerves are branches of the mandibular nerve (CN V3) that innervate the temporalis muscle, which is involved in chewing, but do not affect sensation in the temporal region or the parotid gland.
• The facial nerve (CN VII) innervates the muscles of facial expression and provides parasympathetic fibers to the lacrimal, submandibular, and sublingual glands, but does not have a direct role in the sensory innervation of the temporal region or the parotid gland.

Infraorbital Nerve and Facial Pain

• An elderly man experiencing severe pain beneath the left eye, radiating into the lower eyelid, lateral side of the nose, and upper lip, is most likely experiencing issues with the infraorbital nerve.
• The infraorbital nerve is a branch of the maxillary division (V2) of the trigeminal nerve (CN V).
• It provides sensory innervation to the skin below the eye, including the lower eyelid, lateral side of the nose, and upper lip.
• The patient's severe pain in this area is typical of the sensory distribution of the infraorbital nerve.
• This pain could be indicative of trigeminal neuralgia or other causes of nerve compression or irritation.
• The buccal nerve is a branch of the mandibular division (V3) of the trigeminal nerve and provides sensory innervation to the cheek and the inside of the cheek (buccal mucosa), but would not affect the above regions.
• The mental nerve is also a branch of the mandibular division (V3) and provides sensory innervation to the skin of the chin and lower lip, but not the area affected in this case.
• The supratrochlear nerve is a branch of the ophthalmic division (V1) of the trigeminal nerve and provides sensory innervation to the forehead, but does not affect the areas mentioned in the question (below the eye, nose, or upper lip).

Zygomatic Bone Fracture:

• A forty-year-old man sustains a blow to the face during a fight and develops swelling and bruising over his cheek, and examination shows a deformity around the zygomatic arch. Impaired sensation over the cheek is the most likely symptom to occur with a fracture of the zygomatic bone.
• The maxillary division (V2) of the trigeminal nerve provides sensory innervation to the cheek, upper lip, and nasal cavity.
• A zygomatic fracture can damage the V2 branches, causing impaired sensation over the cheek.
• Additionally, fractures in this region may also affect the infraorbital nerve, a branch of V2.

Mandibular Fracture and Nerve Involvement:

• A 29-year-old man presents to the emergency room after a motor vehicle accident and has pain and swelling of the lower jaw and has difficulty opening his mouth. The patient is unable to move his lower lip and chin due to a fracture of the mandible. The nerve most likely affected is the mandibular division of the trigeminal nerve (CN V3).
• The mandibular division (V3) of the trigeminal nerve provides motor innervation to the muscles of mastication (e.g., masseter, temporalis, medial pterygoid).
• A fracture of the mandible affects the motor innervation, causing difficulty with mouth opening and muscle paralysis, along with sensory loss to the lower face.

Pneumothorax and Ventilation Muscles

• A 27-year-old male is stabbed in the left side of his chest, exhibits decreased breath sounds on the left side of the chest, and a chest x-ray confirms a pneumothorax. The external intercostal muscles is the muscle group most likely to have ventilation changes.
• The external intercostal muscles elevate the ribs during inspiration and are essential in normal breathing mechanics.
• A pneumothorax compromises lung expansion and restricts the action of the intercostal muscles on the affected side.

Internal Thoracic Artery and Hemothorax

• A 25-year-old female presents with a traumatic injury to the thoracic wall, and imaging reveals a hemothorax. The internal thoracic artery is likely responsible for the blood accumulation in the pleural space.
• The internal thoracic artery runs along the inner surface of the anterior thoracic wall.
• It can be damaged in traumatic injuries, leading to blood accumulation in the pleural cavity, causing a hemothorax.
• The internal thoracic artery is a branch of the subclavian artery.
• The internal thoracic artery is also called the mammary artery.
• The branches of the internal thoracic artery include the anterior intercostal arteries, perforating branches, musculophrenic artery, superior epigastric artery and Pericardiacophrenic.

Anterior Mediastinum Mass and Structure Compression

• A 45-year-old male exhibits swallowing difficulty and chest fullness, imaging reveals a mass in the anterior mediastinum. The thymus is the structure most likely to be affected by this mass.
• The thymus is situated anterior to the heart and great vessels, and masses there cause symptoms like difficulty swallowing or chest discomfort.

Superior Mediastinum and Structure Compression

• A 58-year-old woman presents with shortness of breath and an X-ray shows a mass in the superior mediastinum. The trachea could be compressed by this mass.
• The superior mediastinum contains the trachea, esophagus, and major blood vessels.
• A mass in this region could compress the trachea, leading to symptoms like difficulty breathing or stridor.

Vagus Nerve and Diaphragm Passage

• A 36-year-old male undergoing thoracic surgery for a mediastinal mass, has the surgeon identifying a structure that passes through the diaphragm at the level of the T10 vertebra and is involved in the autonomic control of the heart and digestive tract. The vagus nerve is the most likely involved structure.
• The vagus nerve (cranial nerve X) passes through the diaphragm at the T10 level.
• Is innervates various organs in the thorax and abdomen, including the heart, lungs, and digestive tract.

Left Recurrent Laryngeal Nerve and Hoarseness

• A 50-year-old male presents with a persistent cough and hoarseness, and imaging shows a tumor in the left lung apex. The left recurrent laryngeal nerve is the structure in the mediastinum most likely being compressed
• The left recurrent laryngeal nerve loops around the aortic arch in the mediastinum before ascending to the larynx.
• A tumor in the apex of the left lung, particularly in the region of the left subclavian artery or aortic arch, could compress this nerve, leading to hoarseness (a condition known as Horner's syndrome).

Posterior Mediastinum Structures

• A 25-year-old woman presents with chest pain and difficulty breathing; a CT scan shows a mass in the posterior mediastinum. Esophagus is the primary structure located in the posterior mediastinum
• The posterior mediastinum primarily contains the esophagus, descending aorta, thoracic duct, and sympathetic trunks.
• A mass in this region could potentially compress the esophagus, leading to dysphagia or chest pain.

Pleural Effusion and Lung Expansion

• A 55-year-old male, has a history of difficulty breathing and chest pain. The patient presents with reduced movement of the chest wall during breathing with further imaging revealing a pleural effusion on the right side.
• Pleural effusions can restrict the expansion of the lungs and chest wall due to fluid accumulation in the pleural space.
• The parietal pleura, which lines the thoracic wall, is sensitive to pain and could contribute to symptoms of chest pain in this case.

Mediastinum Structures

• The left ventricle of the heart is NOT contained within the superior mediastinum.
• The trachea, esophagus, and other structures such as the brachiocephalic veins and thoracic duct are found in this area.
• The left ventricle is located in the middle mediastinum.

Long Thoracic Nerve and Shoulder Weakness

• After a resection of the 4th intercostal space for a 48 yr old women she had an axillary shoulder surgery. She developed difficulty in raising her arm and has weakness of shoulder movements.
• The long thoracic nerve innervates the serratus anterior muscle, which is important for shoulder movements, particularly protraction and abduction of the arm.

Rib Fracture and Pulmonary Damage

• A 35-year-old man has a rib fracture after a motor vehicle accident. His lung is not expanding properly with the most likely damaged structure being the costal pleura.
• The costal pleura is the part of the parietal pleura adjacent to the ribs.
• Damage to the pleura may lead to a pneumothorax or restrict lung expansion.

Emphysema and Lung Compliance

• A 60 year old with SOB and cough with smoking hx is diagnosed with emphysema with increased lung compliance.
• Emphysema: destructions of alveolar walls leads to a loss of elasticity in the lungs. Increased lung compliance means lungs can expand more easily, but they do not recoil efficiently, leading to difficulty with exhalation.

Breast Cancer:

• Therapeutic intervention with a patient with a 54 year old woman with right side breast cancer.
• Axillary Lymph nodes would metastasize and be the important place for Lymph.
• 75% of the lymph nodes in the breast goes to the axillary lymph node. Lymph eventually drain into the subclavain lymph trunk.
• Most of the rest lymph drain to the Parasternal lymph nodes. The anterior mediastinum is not as important as the lymphatic drainage.

Field Hockey Fracture

• A jarring blow to the left shoulder area caused a muscle tear that resulted from superolateral distraction directly from a fractured coracoid process. Which muscle was torn?
• Pectoralis minor muslce is where the tear occurred.

Paralysis of the Pectoralis Major Muscle:

• A 16yo paralyzed after thrown off motorcycle. Which set of movements that would greatly weaken?
• The major flexes, adducts, and medially rotates the arm. It is innervated by the lateral and medial pectoral nerve from the brachial plexus.

Routes of Metastasis and Breast Cancer

• The most direct route spread Breast Cancer Via Branches of intercostal veins directly.

Clamping Off of Arterial Flow:

• Necessary to sometimes clamp off all blood Flow in surgery of Heart. This can be done in the pericardial sac.
• To do this insert the index finger immediately behind the two great arteries (Aorta and pulmonary Trunk) and Anterior to the Superior Vena Cava with Thumb of the two hands.

Fluid Accumulation (thorax)

• 68yr old has copious fluid on the left from Pleurisy. Where is the best area to Examine?
• It gathers at the costophrenic recess because it is the lowest.

Heart Chamber and sternocostal Surface

• The strenocostal surface of the heart if formed primarily by what heart chamber?
• It is formed by the Right Ventricle.

MVA incident and sternum

• Anterior surface of the heart is formed by what Heart chamber? The right ventricle.

Brittle Posterior Wall and Bronchial Examination

• Suspected of widespread cancer the instrumental Bronchscope punctures thin Brittle diseased right main Bronchus what is also torn A?
• THe azygos vie
• The azygos vein lies immediately behind the right mainstem bronchus.

Surgeon and Explatory Surgery:

• What side of Azygos will aorta is thoracic duct found in during surgery of explore incident.
• The Thoracic duct lies in the posterior mediastinum between the aorta and on either side.

Sweat Glands

• Cervicothoracic (Stellate) Ganglion are used to treat?
• To stop sweat gland from forming.
• *The cervicothoracic ganglion is a sympathetic ganglion.

Vertebra and Canerous Growth

• What is the part in direct contact when coming from the 9th thoracic vertebra during a growth?
• *The Right Splaughnic nerve.
• The greater thoracic splanchnic nerve is on the vertebrae.

Lymph harvest cut?

• Chlyothorax with cut during procedures. Cut of the Lymph system
• chylothorax is a pleural effusion composed of lymphatic fluid due to disruption of the thoracic duct

Azgous Arch blockage?

• What would the collateral Drainage do to a azgos venous arch?
• Internal Thoraci Vein would be come distend.

Transesophageal

• During transepophageal echocardiogry?
• Middle media is found with the infection.

Hart sounds listening device

• Where in the rib to you hear at
• Rib 2 is where you can hear the atriotic valve.

Coronary Bye pass?

• The great vein is used, but what side? – The Anterior

Compression MVA

• Where heart damage comes from blunt trauma the what side is the damange?

Heart and Chest area.

Cardiac Tamponade

• The safest area for syringe to be inserted to miss the pleura is?
• Just to be blow the left of the Xphsternal Junction.