Presentation
History of recurrent seizures, post-ictal confusion, recent complaints of quadriparesis and headache.
Patient Data
A small rounded mixed signal intensity lesion is seen in the right posterior temporal region. It displays heterogeneous signal intensity on T1 & T2 WI; however, it mostly shows hyperintense SI on T1 WI (due to met-hemoglobin) and surrounded by a signal void rim of hemosiderin, indicating old hemorrhage, showing blooming effect on gradient echo. This ‘popcorn’ appearance is typical of cavernous angioma.
Multiple small/ tiny foci of susceptibility-induced signal dropout (blooming on SWI) suggesting microhemorrhages are scattered randomly at the grey-white matter interface of both cerebral hemispheres, as well as cortical, subcortical, lobar and brainstem (involving pons). These are much less evident ot conventional images (most of them are inconspicuous on T1W, T2W and FLAIR images).
Minimal bilateral, rather symmetrical, patchy areas of high T2/FLAIR signal intensity are noted in the cerebral deep periventricular white matter, inconspicuous on the T1 series. No perifocal edema or notable mass effect detected.
Multiple small focal areas of high T2 and FLAIR signal intensity are noted at both frontoparietal subcortical & deep periventricular white matter, inconspicuous on the T1 series.
No evidence of recent cerebral ischemic onset (i.e. restricted diffusion).
Asymmetrical mild swelling of the left mesial temporal lobe with associated exaggerated hyperintensity in T2 & FLAIR. No associated significant mass effect on the temporal horn of the lateral ventricle. Similar, milder changes were seen on the right.
Mildly dilated cortical sulci, Sylvian fissures, extra-axial CSF spaces, as well as the cerebral ventricular system, suggest cerebral involutional changes.
The arrows on magnified images highlight the 'popcorn' appearance of the right temporal cavernoma with blooming on gradient echo.
Axial gradient/ T2* images revealed multiple scattered blooming foci, denoting microhemorrhages.
Case Discussion
Cerebral cavernous malformations (CCM) may occur as a sporadic form or as a familial form, which is far less common. In familial multiple cavernous malformation syndrome, also known as familial cerebral cavernous malformation (FCCM), an autosomal dominant pathology, there are multiple CCM (five or more) or the presence of CCM in at least two members of a family or the mutations in one of the three genes causing this disease.
GRE or SWI sequences promote intensification of the magnetic susceptibility effect (i.e. blooming effect), resulting in in the visual impression of increased lesion volume.
The differential diagnosis for multiple punctuate foci of susceptibility is as follows:
familial multiple cavernous malformation syndrome (type IV) according to the Zabramski classification of cerebral cavernomas
cerebral amyloid angiopathy (probable CAA according to modified Boston criteria)
microhemorrhages of hypertensive microangiopathy
other less likely possibilities such as hemorrhagic metastasis, diffuse axonal injury, and neurocysticercosis, cannot be totally excluded