Hypertensive intracerebral hemorrhage

Hypertensive intracerebral hemorrhages are the most common type of intracerebral hemorrhage (ICH) by cause, commonly affecting the basal ganglia, thalamus, pons or cerebellum.

Epidemiology

Hypertension is the single most important risk factor for ICH, with hypertensive patients 3.5x more likely to have ICH than non-hypertensive patients ⁵. Globally, uncontrolled hypertension accounts for ~75% of the risk for ICH ⁷.

Clinical presentation

Patients will present depending on the region and size of the hemorrhage:

• basal ganglia hemorrhage usually presents with an ipsilateral deviation of the eyes due to descending capsular pathways from the frontal eye field

• thalamic hemorrhage often presents with a downward deviation of the eyes and a lack of pupillary response to light

• pontine hemorrhage usually causes coma due to disruption of the reticular activating system (unless small) and quadriparesis due to disruption of the corticospinal tract ⁴

• cerebellar hemorrhage usually presents with typical "posterior circulation symptoms" of vertigo, ataxia, nausea, vomiting and headache ⁶

Pathology

Long-standing poorly-controlled hypertension leads to a variety of pathological changes in the vessels:

• microaneurysms of perforating arteries (Charcot-Bouchard aneurysms) 

  • small (0.3-0.9 mm) diameter 

  • occur on small (0.1-0.3 mm) diameter arteries

  • distribution matches the incidence of hypertensive hemorrhages

    • 80% lenticulostriate

    • 10% pons

    • 10% cerebellum

  • found in hypertensive patients

  • may thrombose, leak (see cerebral microhemorrhages) or rupture ²

• accelerated atherosclerosis: affects larger vessels

• hyaline arteriosclerosis

• hyperplastic arteriosclerosis: seen in very elevated and protracted cases

Radiographic features

Imaging findings will depend on the location and time since bleeding, which are covered in the intracerebral hemorrhage article.

MRI

When hypertensive microangiopathy is present, multiple small areas of blooming artifact may be evident on GRE or SWI sequences in addition to the ICH.

Treatment and prognosis 

Hemorrhage causes displacement of brain tissue, but once resorbed, the patient recovers with fewer deficits compared to similar-sized infarcts. Treatment of uncontrolled hypertension is very important to prevent recurrent ICH ⁷.

Characteristics of hypertensive hemorrhages that lead to poorer prognosis include ³: 

• bleed in the posterior fossa 

• large amount of mass effect 

• extension into the ventricular system 

Video