AIM • KMU Exam Practice

Question:

A 66-year-old man develops sudden left-sided weakness due to occlusion of a cerebral artery. In the affected neurons, energy production rapidly falls and intracellular water begins to accumulate before irreversible necrosis develops. Which cellular event most directly initiates this swelling?

Options:

• Activation of collagen-producing fibroblasts
• Accumulation of extracellular hemosiderin
• ATP depletion with failure of membrane ion pumps
• Proliferation of reactive astrocytes
• Deposition of amyloid in cortical vessels

Correct Answer: ATP depletion with failure of membrane ion pumps

Explanation: Ischemia reduces oxygen and glucose delivery, causing ATP depletion. Failure of ATP-dependent ion pumps allows sodium and water to enter cells, producing cytotoxic swelling.

Question:

A 58-year-old woman is resuscitated after a prolonged cardiac arrest. She survives but develops prominent impairment of recent memory. Which neuronal population is particularly vulnerable to severe global cerebral ischemia and may contribute to this deficit?

Options:

• Hippocampal pyramidal neurons
• Choroid plexus epithelial cells
• Dural connective-tissue cells
• Ependymal cells lining ventricles
• Leptomeningeal fibroblasts

Correct Answer: Hippocampal pyramidal neurons

Explanation: Certain neurons are selectively vulnerable to global ischemia. Hippocampal neurons are particularly sensitive, so injury may contribute to memory impairment after severe cerebral hypoperfusion.

Question:

A 71-year-old patient presents soon after developing sudden unilateral weakness. Non-contrast CT shows no intracranial blood, but the radiologist suspects an early cerebral infarct. Which finding would support this interpretation?

Options:

• Dense blood filling the basal cisterns
• Rounded hyperdensity within the thalamus
• Generalized enlargement of the ventricles
• Calcification along the cortical surface
• Loss of gray-white differentiation with sulcal effacement

Correct Answer: Loss of gray-white differentiation with sulcal effacement

Explanation: Early ischemic edema may blur normal gray-white differentiation and efface cortical sulci before a mature low-density infarct becomes obvious.

Question:

A 62-year-old woman presents with a new focal neurological deficit. Initial CT excludes hemorrhage but remains equivocal for early infarction. MRI is performed to evaluate the suspected acute ischemic area. Which finding most strongly supports acute cerebral ischemia?

Options:

• Diffuse meningeal calcification
• Restricted diffusion in affected brain tissue
• Uniform enlargement of all ventricles
• Diffuse thickening of the cranial bones
• Symmetrical enhancement of the meninges

Correct Answer: Restricted diffusion in affected brain tissue

Explanation: Acute ischemic cellular swelling restricts water movement. Diffusion-sensitive MRI therefore provides a sensitive radiological clue to early infarction.

Question:

A 69-year-old man with marked atherosclerotic disease develops progressive focal neurological symptoms that become fixed. He has no atrial fibrillation or other identified cardiac embolic source. Which mechanism best explains the cerebral arterial occlusion?

Options:

• Rupture of a cortical aneurysm
• Obstruction of ventricular CSF flow
• Amyloid deposition in meningeal vessels
• Local thrombosis on an atherosclerotic plaque
• Bleeding from a vascular malformation

Correct Answer: Local thrombosis on an atherosclerotic plaque

Explanation: Atherosclerotic arterial disease can produce local thrombus formation and vessel occlusion, resulting in a thrombotic ischemic stroke.

Question:

A 55-year-old man remains without effective circulation for several minutes during cardiac arrest before successful resuscitation. He subsequently has widespread neurological dysfunction rather than a single focal deficit. Which process best explains the brain injury?

Options:

• Diffuse neuronal injury from global cerebral ischemia
• Focal embolization to one cortical artery
• Rupture of a deep penetrating vessel
• Isolated obstruction of the fourth ventricle
• Rupture of a single saccular aneurysm

Correct Answer: Diffuse neuronal injury from global cerebral ischemia

Explanation: Cardiac arrest causes a generalized fall in cerebral perfusion. Prolonged global ischemia can therefore injure widely distributed vulnerable neurons rather than one arterial territory.

Question:

A 73-year-old patient receiving anticoagulant therapy develops sudden headache, weakness and reduced consciousness. CT demonstrates a large spontaneous intraparenchymal hemorrhage. Which mechanism most directly increased the likelihood of this bleeding event?

Options:

• Enhanced astrocytic scar formation
• Increased cerebrospinal fluid absorption
• Impaired coagulation permitting continued bleeding
• Accelerated neuronal glucose utilization
• Improved collateral arterial circulation

Correct Answer: Impaired coagulation permitting continued bleeding

Explanation: Disturbed hemostasis predisposes to spontaneous intracranial hemorrhage and can increase the extent of bleeding once a vessel ruptures.

Question:

A 32-year-old man with no history of hypertension develops an acute intracerebral hemorrhage. Vascular imaging shows a cluster of abnormal communicating vessels at the site of bleeding. Which underlying lesion best explains the hemorrhage?

Options:

• Atherosclerotic narrowing of a carotid artery
• Small deep lacunar infarction
• Diffuse cerebral hypoperfusion
• Thrombotic occlusion of a cortical artery
• Rupture of an intracranial vascular malformation

Correct Answer: Rupture of an intracranial vascular malformation

Explanation: Abnormally formed intracranial vessels can rupture and produce spontaneous cerebral hemorrhage, particularly when common hypertensive causes are absent.

Question:

A patient with intracerebral hemorrhage becomes progressively less responsive despite imaging showing no significant increase in hematoma size. CT demonstrates increasing edema around the hematoma and greater displacement of adjacent structures. Which process best explains the deterioration?

Options:

• Improved collateral arterial perfusion
• Rising intracranial pressure from hematoma and edema
• Resolution of surrounding tissue compression
• Restoration of normal cerebral autoregulation
• Increased clearance of necrotic tissue

Correct Answer: Rising intracranial pressure from hematoma and edema

Explanation: Perihematomal edema adds to the space-occupying effect of the blood collection. Increasing intracranial pressure and tissue displacement can therefore worsen consciousness even without major rebleeding.

Question:

During assessment of a 50-year-old woman with a ruptured saccular aneurysm, the clinician reviews factors that may have contributed to the event. Which combination from the history is most relevant to aneurysmal subarachnoid hemorrhage?

Options:

• Asthma, iron deficiency and migraine
• Hypothyroidism, anemia and osteoarthritis
• Peptic ulcer disease, eczema and myopia
• Hypertension, tobacco exposure and familial predisposition
• Gallstones, obesity and allergic rhinitis

Correct Answer: Hypertension, tobacco exposure and familial predisposition

Explanation: Hypertension and tobacco exposure are important modifiable associations with aneurysmal SAH, while familial or inherited predisposition may increase susceptibility.

Question:

A patient with aneurysmal subarachnoid hemorrhage undergoes an open cranial procedure. The surgeon places a clip across the neck of the aneurysm. Which therapeutic principle best describes this procedure?

Options:

• Remove the surrounding infarcted cortex
• Occlude the parent artery completely
• Exclude the aneurysm while preserving the parent artery
• Drain all blood from the subarachnoid space
• Remove the affected arterial branch

Correct Answer: Exclude the aneurysm while preserving the parent artery

Explanation: Microsurgical clipping closes the aneurysm neck so that blood no longer enters the aneurysm while maintaining flow through the parent vessel.

Question:

A 60-year-old patient with a surgically accessible lobar intracerebral hematoma develops worsening focal deficits and increasing tissue displacement on serial imaging. What is the principal objective of hematoma evacuation in such a selected patient?

Options:

• Reduce mass effect produced by the hematoma
• Reverse established neuronal necrosis
• Prevent development of atherosclerosis
• Restore all lost cortical functions immediately
• Remove reactive astrocytes around the lesion

Correct Answer: Reduce mass effect produced by the hematoma

Explanation: In selected deteriorating patients, hematoma evacuation aims to relieve compression and mass effect rather than reverse already established neuronal injury.

Question:

Two patients have ruptured intracranial aneurysms. One is treated by microsurgical clipping and the other by an endovascular technique. Which principle best explains why different approaches may be selected?

Options:

• The same technique is preferred for every aneurysm
• Patient age is the only factor that determines treatment
• Headache severity determines the operative approach
• Aneurysm anatomy and patient factors guide treatment choice
• Previous infarct location determines the technique

Correct Answer: Aneurysm anatomy and patient factors guide treatment choice

Explanation: Both clipping and endovascular occlusion can secure an aneurysm. Selection depends on the vascular anatomy and overall clinical circumstances rather than one universal approach.

Question:

A community clinic identifies a high prevalence of diabetes mellitus among adults who later develop ischemic cerebrovascular disease. Which mechanism best explains why diabetes contributes to stroke risk?

Options:

• Increased production of cerebrospinal fluid
• Accelerated endothelial injury and atherosclerosis
• Increased resistance of neurons to hypoxia
• Reduced formation of arterial plaques
• Enhanced repair of damaged cerebral vessels

Correct Answer: Accelerated endothelial injury and atherosclerosis

Explanation: Diabetes promotes vascular endothelial injury and accelerates atherosclerotic disease, thereby increasing the likelihood of cerebral arterial occlusion.

Question:

During a stroke-prevention program, a patient is found to have persistent dyslipidemia. Which pathological consequence provides the strongest link between this finding and future ischemic stroke?

Options:

• Increased drainage of cerebrospinal fluid
• Reduced susceptibility to vascular thrombosis
• Decreased injury to arterial endothelium
• Improved perfusion through penetrating arteries
• Promotion of atherosclerotic plaque formation

Correct Answer: Promotion of atherosclerotic plaque formation

Explanation: Dyslipidemia contributes to atherosclerotic plaque development, increasing the risk of arterial narrowing, thrombosis and subsequent cerebral ischemia.

Question:

A district health team finds that the burden of cerebrovascular disease rises substantially in older age groups even after accounting for several lifestyle factors. Which explanation best describes the epidemiological contribution of aging?

Options:

• Aging eliminates the effect of hypertension
• Older arteries become resistant to atherosclerosis
• Cumulative vascular injury increases cerebrovascular disease
• Cerebral oxygen requirements disappear with age
• Collateral vessels prevent arterial occlusion in older adults

Correct Answer: Cumulative vascular injury increases cerebrovascular disease

Explanation: Increasing age is an important non-modifiable determinant because vascular disease and cumulative arterial injury increase over time.

Question:

A stroke survivor can walk with assistance and communicates normally but remains unable to dress, prepare simple meals or safely perform routine household activities. Which rehabilitation service most directly addresses these difficulties?

Options:

• Occupational therapy
• Diagnostic neuroradiology
• Vascular pathology review
• Neurosurgical clipping
• Speech-language therapy

Correct Answer: Occupational therapy

Explanation: Occupational therapy focuses on restoring independence in activities of daily living such as dressing, eating and safely managing routine household tasks.

Question:

Several weeks after a stroke, a patient has improving motor power but remains forgetful, emotionally withdrawn and unable to adjust to the sudden loss of previous independence. Which rehabilitation component is most appropriate for these continuing problems?

Options:

• Repeated vascular imaging alone
• Long-term immobilization therapy
• Routine neurosurgical intervention
• Cognitive and psychological rehabilitation
• Isolated swallowing rehabilitation

Correct Answer: Cognitive and psychological rehabilitation

Explanation: Stroke rehabilitation should address cognitive impairment and emotional adjustment as well as physical disability, particularly when these limit recovery and participation.

Question:

A man with residual weakness after stroke is medically stable and ready to return home. His family is uncertain how to assist him, and he has difficulty resuming previous social roles. Which intervention most directly supports successful community reintegration?

Options:

• Repeated inpatient CT scanning
• Family and social support
• Long-term bed rest at home
• Routine cerebral angiography
• Delayed rehabilitation until full recovery

Correct Answer: Family and social support

Explanation: Family education and social support help patients adapt to residual disability, maintain independence and reintegrate into home and community life.

Question:

A public-health team follows patients who have survived disabling strokes. The program provides mobility training, support for daily activities and measures to reduce complications of immobility. At which level of prevention is this program primarily operating?

Options:

• Primordial prevention
• Primary prevention
• Secondary prevention
• Screening prevention
• Tertiary prevention

Correct Answer: Tertiary prevention

Explanation: Rehabilitation after established stroke is tertiary prevention because it aims to limit disability, prevent secondary complications and improve functional recovery.