<prompt> The investigation of choice for meningeal carcinomatosis in CNS is:Enhanced MRISPECTPETNCCT  <response>: Ans. A. Enhanced MRI Leptomeningeal carcinomatosis LC refers to diffuse seeding of the leptomeninges by tumor metastases. LC occurs in an estimated 20 of patients diagnosed with cancer and is most commonly found in breast carcinoma, lung carcinoma, and melanoma in adults and hematogenous malignancies and primitive neuroectodermal tumor PNET in children. Contrast-enhanced MRI of the brain and spine is the imaging modality of choice because of its safety, excellent contrast resolution, and multiplanar abilities. 