Definitive diagnosis of cerebrospinal fluid leak into the pleural space using 111In-DTPA cisternography

A 58-year-old woman with a calcified disk extrusion causing severe spinal stenosis underwent T8 to T9 diskectomy and spinal fusion. A postoperative pseudomeningocele was treated with lumbar drain and fibrin glue. Performed for persistent right pleural effusion, CT myelogram failed to show communication between the cerebrospinal fluid (CSF) and pleural space--even on 2-hour delayed images. Subsequent 111In-DTPA cisternogram clearly demonstrated CSF leakage into the right pleural space at 2 hours, and surgical repair yielded good results. Radionuclide cisternography is a highly useful method to detect CSF leak, especially when it is occult on CT yet suspected clinically.