**Question:** White infarct is seen in

A. Hypoxic-ischemic encephalopathy
B. Brain abscess
C. Subarachnoid hemorrhage
D. Brain stem stroke

**Correct Answer:** D. Brain stem stroke

**Core Concept:** White infarct refers to an ischemic infarction, or area of tissue death, affecting the white matter of the central nervous system. The white matter is composed of myelinated axons and is responsible for long-distance communication between different regions of the brain. White infarcts are typically seen in cases of arterial occlusion affecting the perforating arteries supplying the deep white matter.

**Why the Correct Answer is Right:** A brain stem stroke (option D) primarily involves the perforating branches of the basilar artery, which supply the deep white matter of the brain stem. The brain stem is responsible for regulating vital functions such as breathing, heart rate, and consciousness. When the brain stem is affected by an ischemic infarction, it can lead to life-threatening complications like respiratory failure and altered consciousness.

**Why Each Wrong Option is Incorrect:**

A. Hypoxic-ischemic encephalopathy (option A) is a clinical syndrome caused by a disruption in cerebral perfusion that leads to neuronal damage due to hypoxia and ischemia. It is a general term for any ischemic or hypoxic insult to the brain, not specific to white matter infarction.

B. Brain abscess (option B) is a localized collection of pus caused by bacterial infection, usually involving the gray matter of the brain. White matter infarction is unrelated to brain abscess.

C. Subarachnoid hemorrhage (option C) is a type of stroke caused by bleeding into the subarachnoid space, surrounding the brain and spinal cord. White matter infarction is not a direct consequence of subarachnoid hemorrhage.

**Clinical Pearl:** White matter infarctions are often missed diagnoses due to their subtle presentation. They are typically seen in elderly patients with hypertension, diabetes, or other vascular risk factors, and can cause cognitive decline, dementia, or even transient neurological symptoms. Early recognition and imaging investigations (CT or MRI) are essential to identify these infarcts and prevent delayed diagnosis and treatment.