Overpressure radionuclide cisternography and metrizamide computed tomographic cisternography in the detection of intermittent rhinoliquorrheas in children.

The authors present their clinical observations on 25 children treated because of cerebrospinal fluid leakage. In an attempt to improve the detection of rhinorrhea, overpressure radionuclide cisternography (ORNC), combined with the placement of nasal pledgets, was employed in 20 cases. In 16 cases, metrizamide computed tomographic cisternography (MCTC) was performed. In 11 children both types of investigations were done. ORNC was performed as follows: after placing pledgets in each side of the nasopharynx, a lumbar puncture was done and opening, resting CSF pressure was continuously monitored. 99mTc-DTPA (1 ml, 0.5-3.0 mCi) was injected intrathecally and infusion of artificial CSF followed. MCTC was done 1 h after instillation of 5 ml of metrizamide. The rhinorrhea was diagnosed in 14 cases (all cases were verified through operation). In one case with negative ORNC, rhinorrhea was observed 1 week after examination and in the other 4 days after an additional head tap. In the group of MCTC, four results were true-positive, seven true-negative, and five false-negative. Concerning the group of ORNC and MCTC, four cases were false-negative with MCTC, but true-positive in ORNC. In seven cases EEG was performed immediately before and after ORNC and no changes were observed. There were no adverse effects following either type of investigation. In conclusion, the authors state that ORNC seems to be more sensitive in comparison to MCTC in diagnosis of intermittent rhinorrhea. MCTC, however, may be useful for precisely locating the CSF leakage.