Nuclear Imaging of Human CSF Flow Using Ga-67 Citrate and In-111 DTPA

Inclusion Criteria: * Participants must have provided informed consent. * Participants must be 2 years of age or older. * Participants must have known history of LM as established by CSF cytology. * Participants must have an Ommaya reservoir implanted at least 2 days before the study. * Participants with ventriculoperitoneal shunts are eligible as long as the shunt is not in the "open" position during the imaging session. * Participants with adequate renal and hepatic function. Creatinine =\< 1.4 mg/dL Bilirubin =\< 2.0 mg/dL BUN =\< 30 SGOT (AST), alkaline phosphatase =\<3 x upper norm (Institutional norm of SGOT = 7-56 mIU/ml and alkaline phosphatase = 38-126 IU/L.). * Urine analysis within normal limits. * Women of child bearing potential (WOCBP) must have a negative serum B-HCG pregnancy test within 7 days of treatment. WOCBP is defined as not post-menopausal for 12 months or no previous surgical sterilization. Exclusion Criteria: * Participants on concurrent external beam radiation therapy to the brain or spine during the planned nuclear imaging sessions. * Participants on concurrent intrathecal chemotherapy during imaging sessions. * Participants with Karnofsky Performance Scale \<50 or Zubrod Performance Scale \>2. * Participants with known or suspected renal or hepatic disease that have not been adequately treated to achieve normalized liver function tests or renal function tests to the above eligible criteria. * Participants with known history of claustrophobia, a…