Gammasubdurography in the diagnosis of chronic subdural bilateral and communicating effusion in infants.

The results obtained by means of Gammasubdurography (G.S.G.) in 37 infants having chronic subdural bilateral effusions, are presented. The use of this procedure, which consists of unilateral injection of Radioiodinated Human Sero Albumin (RIHSA-I 131), into the subdural effusion, is suggested for the determination of a communication between the two cavities. At the same time it is possible to get valuable information about their exact localization and extension. Once the communication is diagnosed, the treatment proposed is internal or external unilateral drainage. The method is safe and is performed in a short time which permits its use in the screening of these patients, especially in conjunction with Gammaencephalography (G.E.G.) and Computer Tomography (CT), patients to it. The test (G.S.G.) has been used by us since 1979. All our cases are included in this series. All of them had been diagnosed by subdural puncture, transillumination, G.E.G. and or CT Scan, as having bilateral subdural collections. All the patients received a saturated iodine solution, 24 hours in advance and for 10 days, as a thyroid blocking agent, which was administered in the usual oral dosage. The radiopharmaceutical administration was performed through a unilateral subdural puncture in a dose of 50 to 80 microcurie of RIHSA-I 131 with a high specific activity. Immediately after this, sequential analog images were obtained with the patient supine and in anterior and lateral head projections. This was accomplished by using a PICKER DYNA 4 Gammacamera equipped with a medium energy parallel hole collimator. The interval between the images was determined during the test in agreement with the findings.