Cavernous hemangioma of the temporal lobe

Clinical History

A 45-year-old woman was referred for brain MRI, with complaints of headache and mesial temporal lobe seizures for 3 years that were never explored.
Complete neurological examination and cerebral CT were normal.

Imaging Findings

Small subcortical lesion in the parahippocampal gyrus, which is hypersignal in T2, T1 and FLAIR weighted sequence, surrounded by a constant hyposignal on all sequences.
Hippocampal gyrus and right temporal horn show no abnormality.
In axial T2* weighted MRI image, the lesion appears larger because of "blooming effect" caused by local magnetic field inhomogeneity induced by paramagnetic blood products.

Discussion

Cavernous haemangioma (CH) is a benign vascular malformation, consisting of abnormal, dilated vessels within intervening neural tissue. It can affect most organ systems including the central nervous system and represents 5–13% of all intracranial vascular malformations [1].
There is no sex prevalence, and most cases are found between 20 and 40 years of age.
Cavernous haemangiomas are located in the supratentorial region in 75%, and only in 1/6 of all cases in the temporal lobes. They occur frequently sporadically but multiple CHs can be a part of familial cerebral cavernoma.
Clinical symptoms depend of localization of cavernous haemangioma, and are usually insidious; headache seizures and focal neurological deficits are the most common symptoms. [2]
CT appearance is not specific, it can be normal or demonstrate a focal hyperdense lesions with indistinct margins, containing areas of blood or speckles of calcific density.
MRI is the technique of choice for the diagnosis of cerebral CHs. The presence of blood products in various stages of degradation is responsible for the typical MRI signal characteristics of these lesions, which have been described as resembling a “mulberry” or “popcorn” appearance. [3]
CHs appear as a hyperintense lesion with a faint hypointense rim in T1 and lobulated heterogeneous signals with a hypointense rim in T2. The most diagnostic image appears in the gradient-echo MRI which produces a blooming artefact from the magnetic susceptibility effect of haemosiderin.
Combining multiple MRI sequences has largely eliminated misdiagnosis of cavernous angiomas, because they have relatively specific signal characteristics. Additionally, gradient-echo imaging, with its increased sensitivity to susceptibility artefact, is useful in the detection of smaller and concomitant lesions, which may not be detected with traditional sequences. [3]

Differential Diagnosis List

Final Diagnosis

Cavernous haemangioma of the temporal lobe

URL:	https://www.eurorad.org/case/12590
DOI:	10.1594/EURORAD/CASE.12590
ISSN:	1563-4086