[111In-DTPA cisterno SPECT for the diagnosis of CSF rhinorrhea: case report]

The authors report on a patient with postoperative CSF (cerebrospinal fluid) leakage subsequent to transsphenoidal surgery where cisterno SPECT (single photon emission computed tomography) demonstrated the precise location of a CSF fistula. Seven months after surgery, the patient suffered from CSF rhinorrhea and headache. MRI (Magnetic Resonance Imaging) revealed significant contrast on T1-weighted images resulting from measurements in the right sphenoid sinus, which were hyperintense relative to CSF. On the basis of signal intensity differences, MRI could not distinguish between CSF leakage and postoperative scarring. Therefore, we performed cisterno SPECT at the same time as RI cisternography with intrathecal lumbar injection of 111In-DTPA which revealed dramatic accumulation of the tracer in the right sphenoid sinus. The patient underwent re-operation via a transsphenoidal approach, and the CSF leakage was repaired using fat-in-fibrin glue and the sella floor was reconstructed by hydroxyapatite platinge. These results suggest that cisterno SPECT may be useful in identifying the precise location of CSF fistulae, while other techniques fail to show evidence of CSF leakage.