COMPUTED TOMOGRAPHIC FINDINGS OF PRIMARY MALIGNANT LEPTOMENINGEAL MELANOMA IN NEUROCUTANEOUS MELANOSIS

Neurocutaneous melanosis is the association of multiple pigmented cutaneous nevi with primary malignant leptomeningeal melanoma or leptomeningeal melanosis. The diagnostic criteria are leptomeningeal melanosis, abnormal skin pigmentation with giant pigmented nevi, and absence of malignant melanoma in any organs other than leptomeninges. The case of a 16 mth. old boy is presented. No evidence of malignant change was discovered in any of the cutaneous nevi or in any organs other than the leptomeninges, although the possibility of metastases from unsectioned portions of the nevi exists. Metrimazide cisternography shows a pattern of cisternal opacification similar to abnormal contrast enhancement seen in basal arachnoiditis.