Imaging for suspected paediatric ventriculoperitoneal shunt dysfunction: are shunt series X-rays always necessary?

PURPOSE: Based on an initial hypothesis that the abdominal radiograph is rarely useful in the radiographic shunt series (SS), this study sought to determine which components of the SS are useful in identifying and diagnosing shunt dysfunction. This enquiry broadened to evaluate which modalities were most clinically useful in patients who ultimately underwent shunt revision for their suspected dysfunction.

METHODS

Arm1: Abdominal radiographs (AXR) performed over a 2-year period were reviewed retrospectively to identify shunt abnormalities. Arm 2: Retrospective analysis of acute imaging and shunt series was performed on patients who had undergone shunt revision at the same hospital over a 10-year period.

RESULTS

Arm 1: Seventy-five AXR performed were part of a formal SS. Eight reported a shunt abnormality. Two were within the abdomen; both findings were artefactual. Arm 2: One hundred seventy-nine patients are included. Ninety-six had abnormal imaging 72 h prior to revision; most were on CT (n = 67). Thirty-one demonstrated shunt leak, fracture or migration. Ninety-three patients had an SS the week before their revision; only 15% (n = 14) were abnormal.

CONCLUSION

This is a study evaluating the utility of radiographs in paediatric shunt malfunction. SS has low clinical yield; based on our findings, as well as background research, we recommend low-dose CT head (US or MRI) should be used as first line investigation, with tailored use of plain films to assist neurosurgical planning.