Which is a feature of Normal Pressure hydrocephalus –
**Core Concept**
Normal Pressure Hydrocephalus (NPH) is a clinical syndrome characterized by the triad of gait disturbance, dementia, and urinary incontinence, often associated with enlarged ventricles and increased cerebrospinal fluid (CSF) volume. NPH typically presents in the elderly population, with symptoms resulting from impaired CSF circulation and absorption.
**Why the Correct Answer is Right**
The correct answer is related to the clinical presentation of NPH. The classic triad includes gait disturbance, which is often the most prominent symptom. This is due to the increased intracranial pressure causing compression of the cerebral peduncles, leading to ataxia and gait impairment. The increased pressure also results in impaired cognitive function, manifesting as dementia, and urinary incontinence due to the compression of the frontal lobe and the cerebral aqueduct.
**Why Each Wrong Option is Incorrect**
* **Option A:** This is incorrect because hydrocephalus can present with normal pressure on lumbar puncture, but it is not a defining feature of NPH.
* **Option B:** This is incorrect because the triad of gait disturbance, dementia, and urinary incontinence is not specific to NPH, and other conditions can also present with these symptoms.
* **Option C:** This is incorrect because the presence of papilledema is not a characteristic feature of NPH, as the pressure is typically normal on lumbar puncture.
**Clinical Pearl / High-Yield Fact**
NPH often presents with a triad of symptoms, but it can be challenging to diagnose, as the symptoms can be nonspecific and similar to other conditions. A lumbar puncture with measurement of CSF pressure and analysis of CSF dynamics is essential for diagnosis.
**Correct Answer: D. Gait disturbance.**