Question

107. A 73 year old male is brought to the physician by his wife, who is concerned about a rapid functional decline over the past several months. Her husband used to manage the family's finances, but he has become increasingly forgetful, and now is unable to perform this task or even to remember the last few words of a conversation. Over this time, he has also developed difficulty walking, and recently has become incontinent of urine. Mini-mental state examination shows impaired short term memory. Thyroid function tests and serum B12 levels are normal. Which of the following is the most likely finding on CT imaging of the head?

A. Gross atrophy of the caudate nucleus
B. Biconvex, extra-axial area of hemorrhage that does not cross suture lines
C. Multiple ring-enhancing lesions throughout the brain
D. Cortical atrophy and ventricular enlargement
E. Ventricular enlargement without cerebral atrophy

Answer 1

The most likely finding on a CT imaging of the head for a 73-year-old male with rapid functional decline, memory loss, gait difficulty, and incontinence, with normal thyroid and B12 levels, is cortical atrophy and ventricular enlargement indicative of Alzheimer's disease.

Step-by-step explanation:

A 73-year-old male presenting with a rapid functional decline, impaired short-term memory, difficulty walking, and urinary incontinence likely has neurodegenerative changes. Given that thyroid function tests and serum B12 levels are normal, the most common and fitting diagnosis would be Alzheimer's disease. The characteristic finding on a CT imaging of the head for a patient with Alzheimer's disease would be cortical atrophy and ventricular enlargement, reflecting the loss of neuronal tissue and subsequent increase in cerebral ventricular size due to degeneration.

Short-term memory impairment, as seen in the mini-mental state examination, alongside functional decline and urinary incontinence, further supports this diagnosis. The finding of gross atrophy of the caudate nucleus is more indicative of Huntington's disease, while a biconvex, extra-axial hemorrhage that does not cross suture lines would suggest an acute subdural or epidural hematoma. Multiple ring-enhancing lesions throughout the brain could point towards infectious or neoplastic processes, and isolated ventricular enlargement without cerebral atrophy might be seen in conditions such as normal-pressure hydrocephalus. Considering the clinical presentation and the exclusion of other metabolic causes, Alzheimer's disease is the most probable diagnosis with the expected CT findings being cortical atrophy and ventricular enlargement.