Evaluation of CSF shunt patency by means of technetium-99m DTPA

Evaluation of 192 cerebrospinal fluid shunts was performed using 1 mCi of technetium-99m DTPA which was injected into the shunt tubing. This was found to be a safe, simple method of evaluating shunt patency. No complications were noted with this procedure, nor was there any documented case of infection related to the injection of the isotope. The sensitivity of the test for evaluation of patency was 97%, specificity 90%, and accuracy 93%. Various patterns of tracer clearance are noted and discussed. The role on this test as an aid in making management decisions is detailed.