This case demonstrates that CAA-related cSAH may present with recurrent transient monoparesis that closely mimics TIA, and careful evaluation of susceptibility weighted imaging is important for recognizing the underlying hemorrhagic lesion in patients with recurrent stereotyped TFNEs.
An elderly patient with hypertension and CAA-related convexity subarachnoid hemorrhage presented with recurrent transient left upper limb monoparesis.
Initial diffusion-weighted imaging showed a focal hyperintensity over the right frontal convexity, and susceptibility-weighted imaging showed a corresponding hypointense signal consistent with cSAH.
The recurrent episodes of monoparesis were clinically indistinguishable from transient ischemic attacks, even with video recordings available.
Levetiracetam alone did not stop the episodes, but after clobazam was added no further episodes were observed.
Careful evaluation of susceptibility-weighted imaging is important for recognizing hemorrhagic lesions in patients with recurrent stereotyped transient focal neurological episodes.
This report describes one elderly patient with high blood pressure who had repeated short episodes of weakness in the left arm. These episodes looked just like transient ischemic attacks (TIAs, or 'mini-strokes'), and even video recordings of them could not tell the two apart. Brain MRI showed a small area of bleeding on the surface of the right frontal brain, called convexity subarachnoid hemorrhage. It was linked to cerebral amyloid angiopathy, a condition in which amyloid protein builds up in small brain blood vessels. The bleeding was visible on a specific MRI sequence called susceptibility-weighted imaging (SWI). The episodes continued on the anti-seizure drug levetiracetam but stopped after a second drug, clobazam, was added. Because this is a single case, it cannot show that this drug combination works in general. This research suggests that recurrent, stereotyped episodes of transient weakness may sometimes come from surface brain bleeding rather than from a TIA. This matters because the causes call for different care, and the authors highlight careful review of SWI scans as a way to detect the hemorrhage.
Tomari S, Kasuya J, Takashima H. (2026). Transient focal neurological episodes in cerebral amyloid angiopathy-related convexity subarachnoid hemorrhage.. Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology. https://doi.org/10.1007/s10072-026-09503-5