Answer for CoW 01 Oct 2017
Cavernous malformation
Findings
CT: area of hyperdensity noted involving corpus callosum and right frontal lobe MRI: altered signal intensity with multiple punctate T1 hyperintensities noted involving the corpus callosum except splenium and right frontal lobe not suppresed on FLAIR.The entire lesion shows blooming in SWI .No diffusion restriction.No significant contrast enhancement and reduced area of perfusion.
Discussion
Benign vascular hamartoma • Contains masses of closely apposed immature blood vessels ("caverns") • No neural tissue ;lntralesional hemorrhages of different ages • CMs exhibit range of dynamic behaviours (enlargement, regression, de novo formation) General Features Best diagnostic clue • "Popcorn ball" appearance with complete hypointense hemosiderin rim on T2WI MR Location • Occurs throughout CNS ;Brain parenchymal CMs common • Spinal cord rare (more common in patients with multiple CM syndrome) • Extraaxial CMs rare Size • CMs vary from microscopic to giant (> 6 cm) • Majority are 0.5-4 cm Morphology • Discrete, lobulated mass of interwoven vessels • Locules of variable size contain blood products at different stages of evolution • Complete hemosiderin rim surrounds lesion Imaging • CMs vary from microscopic to giant (> 6 cm) • Locules of variable size contain blood products at different stages of evolution • Variable appearance depending on hemorrhage/ stage CT Findings NECT Negative in 30-50% Well-delineated round/ovoid hyperdense lesion, usually < 3 cm 40-60% Ca++ No mass effect unless recent hemorrhage Surrounding brain usually appears normal CECT o Little/no enhancement unless mixed with other lesion (e.g., developmental venous anomaly) CTA o Usually negative MR Findings . TlWI Variable, depending on hemorrhage/stage Common: "Popcorn ball" appearance of mixed hyper-, hypointense blood-containing locules Tl perilesional hyperintensity common (Helps differentiate CM from other hemorrhagicmasses) .T2WI Reticulated popcorn-like lesion most typical Mixed signal core, complete hypointense hemosiderin rim Locules of blood with fluid-fluid levels May show surrounding edema in acute lesions T2* GRE o Prominent susceptibility effect (hypointense "blooming") o Multiple CMs: Numerous punctate hypointense foci ("black dots") on GREscans most common finding . TlWI C+ o Minimal or no enhancement (may show associated venous malformation) . MRA o Normal (unless mixed malformation present) . Large acute hemorrhage may obscure more typical features of CM Angiographic Findings Usually normal ("angiographically occult vascular malformation") Exception: Extradural CM (may be very vascular) Differential diagnosis for"Popcorn Ball" lesion Arteriovenous malformation Hemorrhagic neoplasm Calcified neoplasm
Ref:Diagnostic neuroradiology ,Anne G Osborn Diagnostic imaging,Salzman &Barcovich Grainger & Allisons diagnostic radiology (sixth edition)
CT: area of hyperdensity noted involving corpus callosum and right frontal lobe MRI: altered signal intensity with multiple punctate T1 hyperintensities noted involving the corpus callosum except splenium and right frontal lobe not suppresed on FLAIR.The entire lesion shows blooming in SWI .No diffusion restriction.No significant contrast enhancement and reduced area of perfusion.
Discussion
Benign vascular hamartoma • Contains masses of closely apposed immature blood vessels ("caverns") • No neural tissue ;lntralesional hemorrhages of different ages • CMs exhibit range of dynamic behaviours (enlargement, regression, de novo formation) General Features Best diagnostic clue • "Popcorn ball" appearance with complete hypointense hemosiderin rim on T2WI MR Location • Occurs throughout CNS ;Brain parenchymal CMs common • Spinal cord rare (more common in patients with multiple CM syndrome) • Extraaxial CMs rare Size • CMs vary from microscopic to giant (> 6 cm) • Majority are 0.5-4 cm Morphology • Discrete, lobulated mass of interwoven vessels • Locules of variable size contain blood products at different stages of evolution • Complete hemosiderin rim surrounds lesion Imaging • CMs vary from microscopic to giant (> 6 cm) • Locules of variable size contain blood products at different stages of evolution • Variable appearance depending on hemorrhage/ stage CT Findings NECT Negative in 30-50% Well-delineated round/ovoid hyperdense lesion, usually < 3 cm 40-60% Ca++ No mass effect unless recent hemorrhage Surrounding brain usually appears normal CECT o Little/no enhancement unless mixed with other lesion (e.g., developmental venous anomaly) CTA o Usually negative MR Findings . TlWI Variable, depending on hemorrhage/stage Common: "Popcorn ball" appearance of mixed hyper-, hypointense blood-containing locules Tl perilesional hyperintensity common (Helps differentiate CM from other hemorrhagicmasses) .T2WI Reticulated popcorn-like lesion most typical Mixed signal core, complete hypointense hemosiderin rim Locules of blood with fluid-fluid levels May show surrounding edema in acute lesions T2* GRE o Prominent susceptibility effect (hypointense "blooming") o Multiple CMs: Numerous punctate hypointense foci ("black dots") on GREscans most common finding . TlWI C+ o Minimal or no enhancement (may show associated venous malformation) . MRA o Normal (unless mixed malformation present) . Large acute hemorrhage may obscure more typical features of CM Angiographic Findings Usually normal ("angiographically occult vascular malformation") Exception: Extradural CM (may be very vascular) Differential diagnosis for"Popcorn Ball" lesion Arteriovenous malformation Hemorrhagic neoplasm Calcified neoplasm
Ref:Diagnostic neuroradiology ,Anne G Osborn Diagnostic imaging,Salzman &Barcovich Grainger & Allisons diagnostic radiology (sixth edition)
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!