American Board of Psychiatry and Neurology (ABPN) Practice Exam 2025 - Free ABPN Practice Questions and Study Guide

The diagnosis of a colloid cyst of the third ventricle is supported by the symptoms of intermittent headaches and periodic drop attacks, along with the expected findings on MRI. Colloid cysts are often located in the third ventricle and can lead to obstructive hydrocephalus due to their position, causing increased intracranial pressure. This can manifest as headaches.

Additionally, when a colloid cyst causes significant blockage of cerebrospinal fluid (CSF) pathways, it may lead to sudden changes in pressure that could precipitate drop attacks, where the individual loses muscle tone and falls unexpectedly.

MRI typically shows a well-defined cystic lesion that is hyperintense on T2-weighted images and may not enhance significantly with contrast, which aligns with the typical imaging characteristics of a colloid cyst.

In contrast, the other potential diagnoses typically present with differing clinical manifestations and radiographic features. For example, choroid plexus papillomas may lead to hydrocephalus but often cause more persistent symptoms and have a distinct appearance on imaging. Ependymomas generally occur along the central canal of the spinal cord or in the ventricular system and present with different symptoms, including focal neurological deficits. Pineal region germinomas