Neurosurgery Basics

Neurosurgery Basics US Medical PG Question 1: A 41-year-old woman is brought to the emergency department by ambulance because of a sudden onset severe headache. On presentation, the patient also says that she is not able to see well. Physical examination shows ptosis of the right eye with a dilated pupil that is deviated inferiorly and laterally. Based on the clinical presentation, neurosurgery is immediately consulted and the patient is taken for an early trans-sphenoidal surgical decompression. Which of the following will also most likely need to be supplemented in this patient?

• A. Erythropoietin
• B. Aldosterone
• C. Parathyroid hormone
• D. Insulin
• E. Corticosteroids (Correct Answer)

Neurosurgery Basics Explanation: ***Corticosteroids*** - This patient's presentation of sudden onset headache, visual disturbance, **ptosis of the right eye with a dilated pupil deviated inferiorly and laterally** strongly suggests a pituitary apoplexy, a life-threatening condition caused by hemorrhage or infarction of the pituitary gland. Patients with pituitary apoplexy can develop **adrenal insufficiency** due to disruption of the hypothalamic-pituitary-adrenal axis, necessitating immediate corticosteroid supplementation. - Neurosurgical decompression, especially **trans-sphenoidal surgery**, can further stress the adrenal axis and worsen adrenal insufficiency, making postoperative corticosteroid replacement vital to prevent **adrenal crisis**. *Erythropoietin* - **Erythropoietin** is a hormone involved in red blood cell production, primarily used to treat **anemia**, particularly in chronic kidney disease. - While patients undergoing surgery might experience some blood loss, there is no direct indication from the clinical presentation or immediate post-surgical needs for erythropoietin supplementation in this acute setting. *Aldosterone* - **Aldosterone** is a mineralocorticoid primarily involved in regulating blood pressure through sodium and potassium balance. - While adrenal insufficiency associated with pituitary apoplexy can lead to reduced aldosterone production, the primary life-threatening concern is **cortisol deficiency**, which is addressed by corticosteroid (glucocorticoid) supplementation. Aldosterone replacement is rarely the immediate and sole priority in acute adrenal crisis. *Parathyroid hormone* - **Parathyroid hormone** is crucial for **calcium and phosphorus regulation**. - There is no clinical information or direct physiological link between pituitary apoplexy or its surgical management and an immediate need for parathyroid hormone supplementation. *Insulin* - **Insulin** is a hormone essential for glucose metabolism and is primarily used to treat **diabetes mellitus**. - While pituitary dysfunction can sometimes lead to changes in glucose regulation, there is no immediate indication for insulin supplementation based on the presented symptoms of pituitary apoplexy. **Hypoglycemia** can be a concern with adrenal insufficiency if not managed with glucose and glucocorticoids, but insulin itself is not typically supplemented unless the patient has pre-existing or stress-induced hyperglycemia.

Neurosurgery Basics US Medical PG Question 2: The surgical equipment used during a craniectomy is sterilized using pressurized steam at 121°C for 15 minutes. Reuse of these instruments can cause transmission of which of the following pathogens?

• A. Non-enveloped viruses
• B. Sporulating bacteria
• C. Prions (Correct Answer)
• D. Enveloped viruses
• E. Yeasts

Neurosurgery Basics Explanation: ***Prions*** - Prions are **abnormally folded proteins** that are highly resistant to standard sterilization methods like steam autoclaving at 121°C, making them a risk for transmission through reused surgical instruments. - They cause transmissible spongiform encephalopathies (TSEs) like **Creutzfeldt-Jakob disease**, where even trace amounts can be highly infectious. *Non-enveloped viruses* - Non-enveloped viruses are generally **more resistant to heat and disinfectants** than enveloped viruses but are typically inactivated by recommended steam sterilization protocols. - Standard autoclaving conditions are effective in destroying most non-enveloped viruses. *Sporulating bacteria* - **Bacterial spores**, such as those from *Clostridium* or *Bacillus*, are known for their high resistance to heat and chemicals, but are usually **inactivated by steam sterilization at 121°C** for 15 minutes. - This method is specifically designed to kill bacterial spores effectively. *Enveloped viruses* - Enveloped viruses are the **least resistant to heat and chemical disinfectants** due to their lipid envelope. - They are readily **inactivated by standard steam sterilization** at 121°C. *Yeasts* - **Yeasts** are eukaryotic microorganisms that are typically **susceptible to heat sterilization**. - They are effectively killed by typical steam autoclaving conditions used for surgical instruments.

Neurosurgery Basics US Medical PG Question 3: A 37-year-old man is presented to the emergency department by paramedics after being involved in a serious 3-car collision on an interstate highway while he was driving his motorcycle. On physical examination, he is responsive only to painful stimuli and his pupils are not reactive to light. His upper extremities are involuntarily flexed with hands clenched into fists. The vital signs include temperature 36.1°C (97.0°F), blood pressure 80/60 mm Hg, and pulse 102/min. A non-contrast computed tomography (CT) scan of the head shows a massive intracerebral hemorrhage with a midline shift. Arterial blood gas (ABG) analysis shows partial pressure of carbon dioxide in arterial blood (PaCO2) of 68 mm Hg, and the patient is put on mechanical ventilation. His condition continues to decline while in the emergency department and it is suspected that this patient is brain dead. Which of the following results can be used to confirm brain death and legally remove this patient from the ventilator?

• A. Electrocardiogram
• B. Apnea test (Correct Answer)
• C. Lumbar puncture and CSF culture
• D. Electromyography with nerve conduction studies
• E. CT scan

Neurosurgery Basics Explanation: ***Correct: Apnea test*** - The **apnea test** is a **mandatory component** of brain death determination according to American Academy of Neurology (AAN) guidelines - It directly confirms the **irreversible absence of brainstem function** by demonstrating no respiratory drive despite adequate stimulus (PaCO2 ≥60 mm Hg or 20 mm Hg rise from baseline) - This patient already has a PaCO2 of 68 mm Hg, making the apnea test particularly relevant for confirmation - Brain death requires both **clinical examination** (absent brainstem reflexes, coma) and a **positive apnea test** to legally declare death and discontinue mechanical ventilation - The apnea test is performed by disconnecting the ventilator, providing supplemental oxygen, and observing for any respiratory effort while PaCO2 rises to adequate levels *Incorrect: CT scan* - While a **CT scan showing massive intracerebral hemorrhage with midline shift** provides anatomical evidence of severe, irreversible structural brain damage, it is **NOT sufficient to confirm brain death** - CT imaging is used to establish the **etiology** and rule out reversible causes, but does not directly test brainstem function - Brain death is a **clinical and functional diagnosis**, not purely an anatomical one—imaging alone cannot confirm cessation of all brain function - A patient can have devastating structural damage on CT but still retain some brainstem reflexes *Incorrect: Electrocardiogram* - An **electrocardiogram (ECG)** measures cardiac electrical activity and provides no information about brain or brainstem function - Cardiac activity commonly persists after brain death due to the heart's intrinsic automaticity - ECG findings are irrelevant to brain death determination *Incorrect: Lumbar puncture and CSF culture* - **Lumbar puncture and CSF culture** are used to diagnose CNS infections (meningitis, encephalitis) or inflammatory conditions - These tests are **completely irrelevant** for brain death diagnosis, which is based on irreversible cessation of all brain function, not infection - In this trauma case with known intracerebral hemorrhage, LP would be contraindicated due to increased intracranial pressure and risk of herniation *Incorrect: Electromyography with nerve conduction studies* - **EMG and nerve conduction studies** assess peripheral nerve and muscle function, used for diagnosing neuromuscular disorders - These tests provide no information about brain or brainstem function - They are not part of brain death determination protocols

Neurosurgery Basics US Medical PG Question 4: A 78-year-old man is brought in to the emergency department by ambulance after his wife noticed that he began slurring his speech and had developed facial asymmetry during dinner approximately 30 minutes ago. His past medical history is remarkable for hypertension and diabetes. His temperature is 99.1°F (37.3°C), blood pressure is 154/99 mmHg, pulse is 89/min, respirations are 12/min, and oxygen saturation is 98% on room air. Neurologic exam reveals right upper and lower extremity weakness and an asymmetric smile. Which of the following is the next best step in management?

• A. Alteplase
• B. MRI brain
• C. CT head (Correct Answer)
• D. Aspirin
• E. CTA head

Neurosurgery Basics Explanation: ***CT head*** - A **non-contrast CT head** is the immediate priority to differentiate between ischemic and hemorrhagic stroke, which is critical for guiding subsequent treatment decisions. - Given the patient's acute neurological deficits (slurred speech, facial asymmetry, weakness) and vascular risk factors (hypertension, diabetes), **stroke is highly suspected**, and identifying intracerebral hemorrhage is crucial before considering thrombolytic therapy. *Alteplase* - **Alteplase** (tPA) is a thrombolytic agent used for acute ischemic stroke, but its administration is **contraindicated in hemorrhagic stroke**. - Initiating alteplase without first ruling out hemorrhage with a CT scan could lead to catastrophic bleeding. *MRI brain* - While an **MRI brain** can provide more detailed imaging of stroke, it is typically **not the initial imaging modality** in the emergency setting due to longer acquisition times and limited availability, especially when emergent differentiation between ischemic and hemorrhagic stroke is needed. - Its use is usually reserved for cases where the CT is inconclusive or for later evaluation. *Aspirin* - **Aspirin** is an antiplatelet agent used in the management of ischemic stroke, but it should **not be given until a hemorrhagic stroke has been ruled out** via CT head. - Administering aspirin in the context of an intracerebral hemorrhage could worsen bleeding. *CTA head* - A **CT angiography (CTA) head** is used to visualize the cerebral vasculature and identify large vessel occlusions, which can guide thrombectomy decisions in ischemic stroke. - However, performing a **non-contrast CT head is a prerequisite** to rule out hemorrhage before proceeding with CTA or any other advanced imaging or therapeutic interventions.

Neurosurgery Basics US Medical PG Question 5: A 57-year-old man was brought into the emergency department unconscious 2 days ago. His friends who were with him at that time say he collapsed on the street. Upon arrival to the ED, he had a generalized tonic seizure. At that time, he was intubated and is being treated with diazepam and phenytoin. A noncontrast head CT revealed hemorrhages within the pons and cerebellum with a mass effect and tonsillar herniation. Today, his blood pressure is 110/65 mm Hg, heart rate is 65/min, respiratory rate is 12/min (intubated, ventilator settings: tidal volume (TV) 600 ml, positive end-expiratory pressure (PEEP) 5 cm H2O, and FiO2 40%), and temperature is 37.0°C (98.6°F). On physical examination, the patient is in a comatose state. Pupils are 4 mm bilaterally and unresponsive to light. Cornea reflexes are absent. Gag reflex and cough reflex are also absent. Which of the following is the next best step in the management of this patient?

• A. Second opinion from a neurologist
• B. Withdraw ventilation support and mark time of death
• C. Electroencephalogram
• D. Repeat examination in several hours
• E. Apnea test (Correct Answer)

Neurosurgery Basics Explanation: ***Apnea test*** - The patient exhibits classic signs of **brain death**, including a **coma**, fixed and dilated pupils, and absent brainstem reflexes (corneal, gag, cough). The next step is to perform an apnea test to confirm the absence of spontaneous respiratory drive. - An apnea test confirms brain death by demonstrating the **absence of respiratory effort** despite a rising pCO2, provided that spinal cord reflexes are not mistaken for respiratory efforts. *Second opinion from a neurologist* - While consulting a neurologist is often helpful in complex neurological cases, the current clinical picture presents such clear signs of brain death that **further confirmatory testing** for brain death (like the apnea test) is more immediately indicated before seeking additional opinions on diagnosis. - A second opinion would typically be sought to confirm the diagnosis or guide management, but establishing brain death requires a specific protocol which is incomplete without the apnea test. *Withdraw ventilation support and mark time of death* - It is **premature to withdraw ventilation** before brain death is unequivocally confirmed by all necessary clinical and confirmatory tests, including the apnea test. - Withdrawing support without full confirmation could lead to ethical and legal issues, as the patient might still have residual brainstem function, however minimal. *Electroencephalogram* - An **EEG** can show absent electrical activity, supporting brain death, but it is **not a mandatory part of the core brain death criteria** in many protocols, especially when clinical signs are clear and an apnea test can be performed. - The primary diagnostic criteria for brain death usually prioritize clinical examination and the apnea test for proving irreversible cessation of all brain functions. *Repeat examination in several hours* - Repeating the examination in several hours is typically done if there are **confounding factors** (e.g., severe hypothermia, drug intoxication) that might mimic brain death, or if the initial assessment is incomplete. - In this case, there are no mentioned confounding factors, and the immediate priority is to complete the brain death protocol with an apnea test, given the current clear clinical picture.

Neurosurgery Basics US Medical PG Question 6: A 27-year-old man presents to the emergency department after being hit by a car while riding his bike. The patient was brought in with his airway intact, vitals stable, and with a C-collar on. Physical exam is notable for bruising over the patient’s head and a confused man with a Glasgow coma scale of 11. It is noticed that the patient has a very irregular pattern of breathing. Repeat vitals demonstrate his temperature is 97.5°F (36.4°C), blood pressure is 172/102 mmHg, pulse is 55/min, respirations are 22/min and irregular, and oxygen saturation is 94% on room air. Which of the following interventions are most likely to improve this patient's vital signs?

• A. Head elevation, sedation, hypertonic saline, hypoventilation
• B. Lower head, sedation, hypertonic saline, hypoventilation
• C. Head elevation, sedation, mannitol, hyperventilation (Correct Answer)
• D. Head elevation, norepinephrine, mannitol, hyperventilation
• E. Lower head, sedation, hypertonic saline, hyperventilation

Neurosurgery Basics Explanation: ***Head elevation, sedation, mannitol, hyperventilation*** - This patient presents with signs of **increased intracranial pressure (ICP)**, indicated by **Cushing's triad** (hypertension, bradycardia, irregular respirations) and a decreased Glasgow Coma Scale (GCS) after head trauma. **Head elevation** to 30 degrees promotes venous outflow from the brain, reducing ICP. - **Sedation** lowers metabolic demand and reduces agitation, which can otherwise increase ICP. **Mannitol** is an osmotic diuretic that rapidly draws fluid from the brain, decreasing cerebral edema. **Hyperventilation** temporarily reduces ICP by causing cerebral vasoconstriction through decreased pCO2. *Head elevation, sedation, hypertonic saline, hypoventilation* - While **head elevation**, **sedation**, and **hypertonic saline** (an alternative osmotic agent to mannitol) are appropriate for ICP management, **hypoventilation** would increase pCO2, causing cerebral vasodilation and worsening ICP. - The combination of effective and ineffective ICP-reducing strategies makes this an incorrect option. *Lower head, sedation, hypertonic saline, hypoventilation* - **Lowering the head** would impede venous drainage from the brain and increase ICP, which is detrimental in this scenario. - As mentioned, **hypoventilation** is contraindicated as it exacerbates cerebral edema and elevated ICP. *Head elevation, norepinephrine, mannitol, hyperventilation* - While **head elevation**, **mannitol**, and **hyperventilation** are appropriate, **norepinephrine** is primarily used to treat hypotension and maintain cerebral perfusion pressure (CPP) if blood pressure is dangerously low. - In this case, the patient is hypertensive (**blood pressure 172/102 mmHg**), so norepinephrine would further increase blood pressure and ICP. *Lower head, sedation, hypertonic saline, hyperventilation* - **Lowering the head** is contraindicated as it directly increases ICP by hindering venous outflow from the brain. - Although **sedation**, **hypertonic saline**, and **hyperventilation** are useful for ICP control, the incorrect positioning makes this option less suitable.

Neurosurgery Basics US Medical PG Question 7: A 77-year-old man is brought to the emergency department by his wife because of headache, nausea, and vomiting for 24 hours. His wife says that over the past 2 weeks, he has been more irritable and has had trouble remembering to do routine errands. Two weeks ago, he fell during a skiing accident but did not lose consciousness. He has coronary artery disease and hypertension. He has smoked one pack of cigarettes daily for 50 years. He has had 2 glasses of wine daily since his retirement 10 years ago. Current medications include atenolol, enalapril, furosemide, atorvastatin, and aspirin. He appears acutely ill. He is oriented to person but not to place or time. His temperature is 37°C (98.6°F), pulse is 99/min, respirations are 16/min, and blood pressure is 160/90 mm Hg. During the examination, he is uncooperative and unable to answer questions. Deep tendon reflexes are 4+ on the left and 2+ on the right. Babinski's sign is present on the left. There is mild weakness of the left iliopsoas and hamstring muscles. A CT scan of the head without contrast shows a high-density, 15-mm crescentic collection across the right hemispheric convexity. Which of the following is the most appropriate next step in the management of this patient?

• A. Recombinant tissue plasminogen activator administration
• B. Obtain an Electroencephalography
• C. Obtain an MRI of the head
• D. Surgical evacuation (Correct Answer)
• E. Observation

Neurosurgery Basics Explanation: ***Surgical evacuation*** - The CT scan reveals a **high-density, crescentic collection**, strongly indicative of an **acute subdural hematoma**, which is causing significant neurological deficits and mass effect (e.g., increased intracranial pressure symptoms like headache, nausea, vomiting, and altered mental status, and focal neurological signs). - Given the patient's **acute neurological decline**, significant mass effect from the 15-mm hematoma, and age, prompt **surgical evacuation** is the definitive treatment to relieve pressure and prevent further brain injury. *Recombinant tissue plasminogen activator administration* - **tPA** is indicated for **acute ischemic stroke**, not hemorrhagic stroke or subdural hematoma. Administering tPA in this context would be harmful, potentially worsening the hemorrhage. - The patient's CT scan clearly shows a **hemorrhagic lesion**, not an ischemic event. *Obtain an Electroencephalography* - **EEG** is primarily used to evaluate **seizure disorders** or certain types of encephalopathy. While the patient has altered mental status, the primary issue identified on CT is a subdural hematoma requiring immediate intervention. - EEG would not provide information relevant to the immediate management of an **acute subdural hematoma**. *Obtain an MRI of the head* - An **MRI** can provide more detailed imaging, but in the context of an **acute subdural hematoma** with significant neurological compromise, it would delay crucial and time-sensitive surgical intervention. - The **CT scan** has already provided sufficient diagnostic information to warrant immediate surgical planning. *Observation* - **Observation** is not appropriate for a patient with a rapidly expanding **acute subdural hematoma** causing significant neurological deficits and a 15-mm collection, especially given the patient's age and clinical presentation. - Delaying treatment would likely lead to further neurological deterioration, **herniation**, and potentially death.

Neurosurgery Basics US Medical PG Question 8: A 62-year-old man is brought to the emergency department after his wife found him unresponsive 1 hour ago. He had fallen from a flight of stairs the previous evening. Four years ago, he underwent a mitral valve replacement. He has hypertension and coronary artery disease. Current medications include aspirin, warfarin, enalapril, metoprolol, and atorvastatin. On arrival, he is unconscious. His temperature is 37.3°C (99.1°F), pulse is 59/min, respirations are 7/min and irregular, and blood pressure is 200/102 mm Hg. The right pupil is 5 mm and fixed. The left pupil is 4 mm and reactive to light. There is extension of the extremities to painful stimuli. The lungs are clear to auscultation. Cardiac examination shows a systolic click. The abdomen is soft and nontender. He is intubated and mechanically ventilated. A mannitol infusion is begun. A noncontrast CT scan of the brain shows a 6-cm subdural hematoma on the right side with an 18-mm midline shift. Which of the following is the most likely early sequela of this patient's current condition?

• A. Multifocal myoclonus
• B. Right eye esotropia and elevation
• C. Bilateral lower limb paralysis
• D. Left-side facial nerve palsy
• E. Right-sided hemiplegia (Correct Answer)

Neurosurgery Basics Explanation: ***Right-sided hemiplegia*** - The patient has a **right-sided subdural hematoma** causing **uncal herniation** with significant midline shift (18 mm). - **Kernohan's notch phenomenon** is a false localizing sign where the contralateral cerebral peduncle (left side) is compressed against the edge of the tentorium cerebelli by the herniating brain. - This contralateral peduncle compression paradoxically produces **ipsilateral hemiplegia** (same side as the lesion) - in this case, right-sided hemiplegia from a right-sided mass. - This is an **early sequela** of severe herniation and represents a classic false localizing sign in neurosurgery. *Multifocal myoclonus* - This indicates widespread cortical irritability or **metabolic encephalopathy** (e.g., uremia, hypoxia, drug toxicity). - Not a typical early focal sequela of subdural hematoma with uncal herniation. - May occur later with diffuse hypoxic brain injury but is not the most likely early finding. *Right eye esotropia and elevation* - **Oculomotor nerve (CN III) palsy** causes the eye to be displaced "**down and out**" (exotropia and depression), not esotropia and elevation. - The right fixed dilated pupil indicates CN III compression from uncal herniation, but this would cause lateral deviation and depression of the eye. - The described eye position is inconsistent with CN III palsy. *Bilateral lower limb paralysis* - Would require **bilateral cerebral involvement** of motor cortices or **spinal cord injury**. - A unilateral subdural hematoma, even with herniation, would not typically cause isolated bilateral lower limb paralysis as an early sequela. - Not consistent with the focal nature of this injury. *Left-side facial nerve palsy* - While **contralateral hemiplegia** (left-sided weakness) would be expected from direct mass effect of a right-sided lesion, isolated facial nerve palsy is less likely. - **Central facial palsy** (upper motor neuron) would affect the lower face and could occur contralaterally, but complete hemiplegia including the face would be more common than isolated CN VII palsy. - Kernohan's notch phenomenon specifically affects the motor pathways in the cerebral peduncle, making ipsilateral hemiplegia the most characteristic early motor sequela.

Neurosurgery Basics US Medical PG Question 9: A 56-year-old man presents to the emergency department with severe chest pain and a burning sensation. He accidentally drank a cup of fluid at his construction site 2 hours ago. The liquid was later found to contain lye. On physical examination, his blood pressure is 100/57 mm Hg, respiratory rate is 21/min, pulse is 84/min, and temperature is 37.7°C (99.9°F). The patient is sent immediately to the radiology department. The CT scan shows air in the mediastinum, and a contrast swallow study confirms the likely diagnosis. Which of the following is the best next step in the management of this patient’s condition?

• A. Ceftriaxone
• B. Oral antidote
• C. Dexamethasone
• D. Surgical repair (Correct Answer)
• E. Nasogastric lavage

Neurosurgery Basics Explanation: ***Surgical repair*** - The presence of **mediastinal air** on CT scan and confirmation of **esophageal perforation** by contrast swallow study indicate a surgical emergency. - **Emergency surgical repair** is crucial to prevent widespread mediastinitis, sepsis, and potential mortality from corrosive ingestion. *Ceftriaxone* - While **antibiotics** like Ceftriaxone might be used as adjuncts to prevent infection, they are not the primary treatment for an established esophageal perforation. - Antibiotics alone will not address the structural defect or contain the leakage of corrosive material into the mediastinum. *Oral antidote* - For corrosive ingestions, administering an **oral antidote** is contraindicated as it can worsen tissue damage or induce vomiting, leading to further esophageal injury. - The immediate priority is managing the perforation, not neutralizing the corrosive agent internally. *Dexamethasone* - **Corticosteroids** like dexamethasone are sometimes considered in the management of corrosive ingestions to reduce stricture formation, but their role is controversial and they are not the initial treatment for an acute perforation. - In an active perforation, corticosteroids would not address the immediate life-threatening issue of mediastinal contamination. *Nasogastric lavage* - **Nasogastric lavage** is contraindicated in corrosive ingestions, especially with suspected or confirmed perforation. - Passing a tube could further injure the already damaged tissue and increase the risk of perforation or exacerbate an existing one.

Neurosurgery Basics US Medical PG Question 10: A 47-year-old man is admitted to the emergency room after a fight in which he was hit in the head with a hammer. The witnesses say that the patient initially lost consciousness, but regained consciousness by the time emergency services arrived. On admission, the patient complained of a diffuse headache. He opened his eyes spontaneously, was verbally responsive, albeit confused, and was able to follow commands. He could not elevate his left hand and leg. He did not remember the events prior to the loss of consciousness and had difficulty remembering information, such as the names of nurses or doctors. His airway was not compromised. The vital signs are as follows: blood pressure, 180/100 mm Hg; heart rate, 59/min; respiratory rate, 12/min; temperature 37.0℃ (98.6℉); and SaO2, 96% on room air. The examination revealed bruising in the right frontotemporal region. The pupils are round, equal, and show a poor response to light. The neurologic examination shows hyperreflexia and decreased power in the left upper and lower limbs. There is questionable nuchal rigidity, but no Kernig and Brudzinski signs. The CT scan is shown in the image. Which of the following options is recommended for this patient?

• A. Lumbar puncture
• B. Decompressive craniectomy
• C. Administration of levetiracetam
• D. Administration of methylprednisolone
• E. Surgical evacuation of the clots (Correct Answer)

Neurosurgery Basics Explanation: ***Surgical evacuation of the clots*** - The CT scan image shows a **biconvex (lenticular) hyperdensity** consistent with an **epidural hematoma (EDH)**, which typically results from arterial bleeding (often from the **middle meningeal artery**). This patient's **"lucid interval"** (initial loss of consciousness, regain consciousness, then deterioration) is classic for EDH. - Given the patient's neurological deterioration (left-sided weakness, pupillary changes, confusion, memory issues) and signs of increased intracranial pressure (hypertension, bradycardia - part of Cushing's triad), urgent surgical evacuation of the hematoma is indicated to relieve pressure and prevent herniation. *Lumbar puncture* - A lumbar puncture is **contraindicated** in the setting of suspected or confirmed **increased intracranial pressure (ICP)**, as it can precipitate **cerebral herniation**. - The CT scan clearly demonstrates a space-occupying lesion, making a lumbar puncture unnecessary and potentially dangerous. *Decompressive craniectomy* - While decompressive craniectomy is a neurosurgical procedure used to reduce ICP, it is generally considered when other measures have failed or in cases of **diffuse brain swelling** or large **intracerebral hematomas** not amenable to simple evacuation. - In this case of a localized epidural hematoma with a clear surgical target, direct evacuation is the primary and most effective intervention. *Administration of levetiracetam* - Levetiracetam is an **anticonvulsant** used to prevent seizures. While seizures can occur after traumatic brain injury, there is no indication that the patient is currently seizing. - Prophylactic anticonvulsants are sometimes used in severe TBI, but addressing the life-threatening hematoma takes **precedence** over seizure prophylaxis. *Administration of methylprednisolone* - **Corticosteroids** like methylprednisolone are generally **contraindicated** in traumatic brain injury (TBI) as studies have shown **worse outcomes** and increased mortality. - They are primarily used for their **anti-inflammatory effects** in conditions like spinal cord injury or vasogenic edema from tumors, not for acute head trauma with hematoma.

Neurosurgery Basics Flashcard 1 of 3

Question: What surgical approach is used in the removal of a pituitary adenoma? _____

Answer: Transsphenoidal resection

Neurosurgery Basics Flashcard 2 of 3

Question: Malignant otitis externa is an emergency that can progress to osteomyelitis of the _____

Answer: skull base

Neurosurgery Basics Flashcard 3 of 3

Question: Depending on the severity of diffuse axonal injury, patients may present with _____

Answer: motor posturing