A 58-year-old man with hypertension presents with acute onset severe headache, vomiting, and right-sided hemiparesis. CT head shows a hyperdense lesion in the left basal ganglia with surrounding edema. Regarding the imaging features of hypertensive intracerebral hemorrhage (ICH), all of the following are true EXCEPT:

Explanation

## Understanding Hypertensive ICH Imaging **Key Point:** Fluid-fluid levels (sedimentation of blood products) are NOT a characteristic feature of hypertensive ICH; they are instead a hallmark of amyloid angiopathy-related hemorrhage and are rare in pure hypertensive bleeds. ### Correct Features of Hypertensive ICH | Feature | Details | |---------|----------| | **Most common location** | Basal ganglia (putamen/external capsule) — 50% of cases; also thalamus, pons, cerebellum | | **CT appearance (acute)** | Hyperdense (spontaneous high attenuation) due to fresh blood | | **Perilesional edema** | Develops over hours, peaks at 5–7 days, then gradually resolves | | **Shape** | Irregular, poorly demarcated margins (unlike lacunar infarcts) | | **Fluid-fluid levels** | NOT typical of hypertensive ICH; suggests amyloid angiopathy or coagulopathy | **High-Yield:** Fluid-fluid levels (hemoglobin-hemoglobin interfaces) indicate slow, recurrent microhemorrhages or coagulopathy-related bleeding — classic in cerebral amyloid angiopathy (CAA), not hypertensive ICH. ### Why Fluid-Fluid Levels Are Rare in Hypertensive ICH Hypertensive hemorrhages occur in a single acute event from rupture of lipohyalinotic vessels. The blood accumulates rapidly and uniformly. Fluid-fluid levels require: - Repeated bleeding episodes (CAA) - Coagulopathy with slow ooze - Settling of red cells in a contained space over time **Clinical Pearl:** If you see fluid-fluid levels in an elderly patient with lobar (not deep) ICH, think amyloid angiopathy first, not hypertension. ### Differential Imaging Features | Hemorrhage Type | Location | Fluid-Fluid Levels | Perilesional Edema | |-----------------|----------|-------------------|-------------------| | **Hypertensive ICH** | Deep (basal ganglia, thalamus, pons) | Absent | Marked | | **Amyloid angiopathy** | Lobar (cortical/subcortical) | Present (characteristic) | Variable | | **Coagulopathy-related** | Variable | May be present | Variable | | **Traumatic** | Epidural/subdural/contusion | Absent | Minimal | **Mnemonic:** **DEEP** = hypertensive ICH locations (basal ganglia, thalamus, pons); **LOBAR** = amyloid angiopathy (and amyloid shows fluid-fluid levels). [cite:Harrison 21e Ch 435]