USMLE (United States Medical Licensing Examination) Step 1 Practice Exam

How does chronic alcoholism affect the cerebellar vermis?

1. Intention tremor

2. Rhythmic "Parkinsonism" tremor

3. Atrophy to the ant lobes

4. Truncal instability

The correct answer is: Atrophy to the ant lobes

Chronic alcoholism has a significant impact on the cerebellar vermis, often leading to atrophy of this region, particularly the anterior lobes of the cerebellum. The cerebellar vermis is crucial for maintaining balance and posture by coordinating signals from the body about position and movement. In the context of chronic ethanol abuse, neurotoxic effects result in the degeneration and atrophy of cerebellar neurons, prominently affecting the anterior lobes. This atrophy contributes to various clinical symptoms, particularly truncal instability, which manifests as unsteadiness while sitting or standing. Patients may struggle with their balance, leading to a wide-based gait and difficulty maintaining posture. This contrasts with other symptoms that might arise due to different pathologies affecting the cerebellum, but in the case of chronic alcoholism, the hallmark finding is the atrophy of the anterior lobes leading to truncal instability. Understanding the relationship between chronic alcoholism and cerebellar atrophy aids in the recognition of clinical symptoms and their underlying causes, which is crucial for effective diagnosis and management.