A 58-year-old man with uncontrolled hypertension presents with acute onset severe headache, vomiting, and focal neurological deficits. CT head shows a hyperdense lesion with mass effect. Which is the most common site of hypertensive intracerebral hemorrhage?

Explanation

## Most Common Site of Hypertensive ICH **Key Point:** Hypertensive intracerebral hemorrhage (ICH) has a characteristic distribution pattern based on the location of lipohyalinosis in penetrating arteries. ### Distribution of Hypertensive ICH | Location | Frequency | Artery Involved | Clinical Features | |----------|-----------|-----------------|-------------------| | **Putamen/External capsule** | **50–60%** | Lenticulostriate arteries | Contralateral hemiparesis, hemisensory loss, homonymous hemianopia | | Thalamus | 15–25% | Thalamoperforating arteries | Sensory loss, vertical gaze palsy, altered consciousness | | Pons/Brainstem | 5–10% | Pontine perforating arteries | Quadriparesis, pinpoint pupils, loss of horizontal eye movements | | Cerebellum | 5–10% | Superior cerebellar artery | Ataxia, headache, hydrocephalus risk | | Lobar (cortical) | 10–20% | Cortical branches | Often indicates amyloid angiopathy in elderly | **High-Yield:** The **putamen and external capsule** account for approximately **50–60%** of all hypertensive ICH cases. This occurs because the lenticulostriate arteries (branches of the middle cerebral artery) are the most common site of lipohyalinotic damage in chronic hypertension. ### Pathophysiology 1. Chronic hypertension → lipohyalinosis of small penetrating arteries 2. Weakening of the arterial wall 3. Rupture of lenticulostriate arteries (most vulnerable) 4. Hemorrhage into the putamen and external capsule region **Clinical Pearl:** A patient with hypertensive ICH in the putamen typically presents with contralateral hemiparesis and hemisensory loss. The proximity to the internal capsule explains the motor and sensory deficits. **Mnemonic:** **PTTCL** — Putamen (50–60%), Thalamus (15–25%), Thalamic/brainstem (5–10%), Cerebellar (5–10%), Lobar (10–20%). ### Imaging Characteristics - **CT:** Hyperdense lesion with surrounding hypodensity (edema) - **MRI:** T1 hyperintensity (acute/subacute), T2 hypointensity (hemosiderin rim in chronic phase) - **Mass effect:** Common, especially with larger hematomas **Warning:** Do not confuse hypertensive ICH distribution with amyloid angiopathy, which typically causes **lobar hemorrhages** in elderly patients without hypertension.