Cerebral Amyloid Angiopathy: An Important Differential Diagnosis of Stroke in the Elderly

Cerebral amyloid angiopathy (CAA) accounts for approximately 10–20% of spontaneous intracerebral haemorrhage (ICH). This figure is thought to be higher in the elderly population. With the increasing life expectancy of our population, we anticipate that the prevalence of CAA- related ICH will increase in tandem. Although CAA-related ICH and hypertension-related ICH are distinct entities based on histopathology and imaging, the clinical presentation of the two conditions is similar. The use of brain computed tomography (CT) scans remain the ICH imaging modality of choice in Malaysia due to its availability, cost, and sensitivity in detecting acute bleeds. On the other hand, the use of brain magnetic resonance imaging (MRI) with susceptibility-weighted imaging (SWI) sequencing enables the clinician to determine the presence of chronic blood products in the brain, especially clinically silent microbleeds associated with CAA. However, the use of brain MRI scans in our country is limited and leads to a blurring of lines when differentiating between hypertension-related ICH and CAA-related ICH. How this misrepresentation affects the management of these conditions is unclear. In this study, we present two cases of ICH to illustrate this point and to serve as a springboard to question current practice and promote discussion.

Stroke thrombolysis at 5.5 hours based on computed tomography perfusion.

A young man was admitted with sudden onset of right-sided weakness. He was assessed in the emergency department, and an immediate computed tomography (CT) perfusion study of the brain was arranged, which showed a left middle cerebral artery territory infarct with occlusion of the M1 segment. There was a significant penumbra measuring approximately 50% of the arterial territory. By the time his assessment was completed, it was 5.5 hours from the onset of symptoms. He was nonetheless administered intravenous recombinant tissue plasminogen activator (rtPA) based on the significant penumbra. He was discharged from the hospital after one week with significant residual deficit. At 2 months clinic follow-up, he showed almost complete recovery with a Modified Rankin Score of 1. We hope to demonstrate that a significant penumbra is an important determinant for good neurological recovery and outcome following stroke thrombolysis, even when patients present outside the 4.5 hours onset-to-treatment time window.