Answer for CoW 03 Sep 2017
Melanoma metastases
Findings
Relatively well defined T1 hyperintense / T2 hypointense lesion noted in pons causing expansion of brain stem with perilesional vasogenic edema. On contrast administration , minimal enhancement noted in subtracted images Another well defined T1 hyperintense foci noted in left occipital lobe.
Discussion
Patient was earlier diagnosed as malignant melanoma of right foot, for which amputation done. In such a patient , above features suggestive of brain secondaries. Melanoma Metastases are characteristically hyperintense on T1WI . Other lesions which can appear hyperintense in TIWI are Cavernoma or Benign Hemorrhage . However typical popcorn appearance is not seen in T2WI . Late subacute hematoma will show restricted diffusion . Malignant melanoma is the third most common cause for cerebral metastases after breast and lung cancers. Most metastases appear hyperdense in CT CNS melanoma metastasis has variable pattern in MRI due to melanin or hemorrhage and presents as Melanotic(hyperintense on T1-weighted images and hypointense on T2-weighted images) and Amelanotic patter(hypo/isointense on T1W1 and hyperintense on T2W1). Hemorrhage in the lesion may have a greater influence on this unique appearance than does melanin. Ref: ISRN Surg. 2011; 2011: 276908. Cerebral Melanoma Metastases: A Critical Review on Diagnostic Methods and Therapeutic Options.
Findings
Relatively well defined T1 hyperintense / T2 hypointense lesion noted in pons causing expansion of brain stem with perilesional vasogenic edema. On contrast administration , minimal enhancement noted in subtracted images Another well defined T1 hyperintense foci noted in left occipital lobe.
Discussion
Patient was earlier diagnosed as malignant melanoma of right foot, for which amputation done. In such a patient , above features suggestive of brain secondaries. Melanoma Metastases are characteristically hyperintense on T1WI . Other lesions which can appear hyperintense in TIWI are Cavernoma or Benign Hemorrhage . However typical popcorn appearance is not seen in T2WI . Late subacute hematoma will show restricted diffusion . Malignant melanoma is the third most common cause for cerebral metastases after breast and lung cancers. Most metastases appear hyperdense in CT CNS melanoma metastasis has variable pattern in MRI due to melanin or hemorrhage and presents as Melanotic(hyperintense on T1-weighted images and hypointense on T2-weighted images) and Amelanotic patter(hypo/isointense on T1W1 and hyperintense on T2W1). Hemorrhage in the lesion may have a greater influence on this unique appearance than does melanin. Ref: ISRN Surg. 2011; 2011: 276908. Cerebral Melanoma Metastases: A Critical Review on Diagnostic Methods and Therapeutic Options.
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
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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!