The utility of the plain radiograph “shunt series” in the evaluation of suspected ventriculoperitoneal shunt failure in pediatric patients

Abstract

To our knowledge, the sensitivity of plain radiography, known as the shunt series, in diagnosing an etiology of ventriculoperitoneal (VP) shunt malfunction in children has not been previously investigated. To determine the accuracy of plain radiography in diagnosing VP shunt failure in children in whom shunt malfunction is clinically suspected. We retrospectively reviewed the charts of 238 children who had undergone plain radiographic examination for evaluation of clinically suspected VP shunt failure over a 5-year period. The results were compared with those of CT, MRI, and nuclear cisternography. Just 6.72% of patients demonstrated plain radiographic signs of shunt failure. Of patients with normal plain radiographs, 43% demonstrated shunt abnormalities on CT, MRI or cisternography. Statistical analysis indicated that no more than 10.46% (P < 0.05) of plain radiographs showed signs of failure and that the sensitivity of plain radiography for the detection of VP shunt failure is no higher than 31%. Furthermore, there was poor agreement between the results of plain radiography and those of CT, MRI and cisternography. Children with clinically suspected VP shunt failure should proceed directly to cross-sectional or nuclear imaging, as plain radiographic examinations have low sensitivity and significant false-negative rates for detecting shunt abnormalities in all-comers. Use of the shunt series should be limited to patients who specifically have suspected mechanical causes of shunt failure.