MedPix Medical Image Database COW - Case of the Week Case Contributor: Nicolae Sarbu Affiliation: ACR Learning File®

MedPix No: History Pt Demographics: Age = 33 y.o. Gender = man A 33-year-old man presented with headache, left hemiparesis, hemihypoesthesia and partial seizures of the left arm for a week. No personal or familial significant history was present. Downloaded by (-1)

MedPix No: EXAM & LABS

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

Haemorrhagic cerebral cavernous malformation NE-CT shows a hyperdense nodular lesion (arrow in a), surrounded by a dense area (star in a), involving the subcortical region of the right precentral gyrus and right superior and middle frontal gyri. On MR, the lesion is hypointense on both T1WI and T2WI (arrow in b, d), has high susceptibility effect on SWI (thin arrow in f), and it is surrounded by a hyperintense area on T1WI and T2WI suggestive of subacute hematoma (star in b, d) and more peripherally, by a thin hypointense hemosiderin ring best visualized on SWI (thick arrow in f). Hyperintense oedema on T1WI is depicted (arrowheads in b). No contrast-enhancement is noticed (c). Legend: NE-CT nonenhanced CT, NE-T1 nonenhanced T1WI, CE-T1 contrast-enhanced T1WI. Downloaded by (-1)

FINDINGS CT followed by MR (Fig. 1a-f) demonstrated a nodular lesion in the right frontal subcortical region, surrounded by an area of hematoma in late subacute stage and by hyperintense perilesional oedema on T1WI.

DIFFERENTIAL DIAGNOSIS What is your Differential Diagnosis? The differential diagnosis was between cerebral cavernous malformation (CCM, cavernoma) and haemorrhagic metastasis.

Diagnosis: Cerebral cavernous malformation. Dx Confirmed by: Pathology.

DISCUSSION Companion Cases: CCM is considered the third most prevalent vascular malformation of the brain, after development venous anomaly (DVA) and capillary telangiectasia, affecting 0.5% to 0.7% of the population. - - Histologically, CCM is formed by dilated capillaries without elastic and muscular tunics, which makes it susceptible to multiple bleedings and explains the MR appearance of haemorrhage in different phases of evolution. It is limited at the periphery by a pseudocapsule of gliotic brain infiltrated by hemosiderin, resulting in a hypointense peripheral ring on T2WI. When associated with DVA, the main hypothesis of the pathogenesis of CCM sustains that the first step is a hyperpressure in a branch of the DVA. This produces high pressure in the capillary bed and chronic microbleeds which stimulate fibroblastic and endothelial proliferation with the final result of CCM. As well, cavernoma can also occur as a result of radiation injury, through a similar mechanism of proliferation and dilatation of the vascular endothelium and capillaries. - - CCM can affect all cerebral regions, albeit it is more frequent in the subcortical areas of frontal and temporal lobes. When situated in the posterior fossa, it has a tendency to involve the pons and the cerebellar hemispheres. One third to one half of CCM are clinically silent. The symptomatology is usually associated with haemorrhagic events. - - There are different forms to classify CCM, the most used being the sporadic versus familial forms and the Zabramski classification. The sporadic form usually presents as a unique lesion and it has strong association with DVA which is commonly adjacent to the CCM and involved in its pathogenesis. On the other hand, the familial form is represented by multiple lesions, has no association with DVA and it does have higher risk of complications. The Zabramski classification is based on the haemorrhagic aspect of CCM and includes: type 1, subacute haemorrhage (hyperintense on T1WI, hyper- or hypointense on T2WI), type 2, *popcorn ball* appearance (mixed-signal intensity on T1- and T2WI, hypointense ring on T2WI), type 3, chronic haemorrhage (iso- or hypointense on T1- and T2WI, also hypointense ring) and type 4, patchy microbleeds (punctate hyperintense lesions on T2*, *black dots*). - - On CT, up to half of CCM cannot be identified, the others being slightly hyperdense, well defined, sometimes with calcifications. The MR appearance is heterogeneous, consequence of different stages of haemorrhage. A hypointense peripheral ring frequently appears on T2WI, explained by the presence of hemosiderin. On T2*-Gradient Recalled Echo (GRE) and Susceptibility-Weighted Imaging (SWI) it manifests high susceptibility magnetic properties, presenting pronounced hypointense signal. When a CCM is studied, the administration of contrast is recommended in order to search for a DVA. The reasons are the high association between the two malformations and, more importantly, when dealing with a surgical CCM, being aware of the presence of a DVA is essential in order to avoid a venous infarct which would result from cutting the DVA. CCM usually does not enhance. Sometimes it is difficult to differentiate a complicated cavernoma from a haemorrhagic neoplasm. Noteworthily, it was showed that hyperintense perilesional signal on T1WI can be seen in more than half of the patients with CCM, this being of particular value when the diagnosis is uncertain and a therapeutic decision is required [AJNR 2008;29:494500]. - - References - -Yun TJ, Na DG, Kwon BJ, Rho HG, Park S-H, Suh Y-L, et al. A T1 hyperintense perilesional signal aids in the differentiation of a cavernous angioma from other hemorrhagic masses. AJNR Am J Neuroradiol 2008;29: Petersen T a, Morrison L a, Schrader RM, Hart BL. Familial versus sporadic cavernous malformations: differences in developmental venous anomaly association and lesion phenotype. AJNR Am J Neuroradiol 2010;31: Zabramski JM, Wascher TM, Spetzler RF, Johnson B, Golfinos J, Drayer BP, et al. The natural history of familial cavernous malformations: results of an ongoing study. J Neurosurg 1994;80: Corts Vela JJ, Concepcin Aramenda L, Ballenilla Marco F, Gallego Len JI, Gonzlez-Spnola San Gil J. Cerebral cavernous malformations: spectrum of neuroradiological findings. Radiologia 2012;54: Al-Shahi Salman R, Hall JM, Horne MA, Moultrie F, Josephson CB, Bhattacharya JJ, et al. Untreated clinical course of cerebral cavernous malformations: a prospective, population- based cohort study. Lancet Neurol 2012;11: