Shunt series

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The shunt series is a set of radiographic images performed to assess the location and integrity of a ventriculoperitoneal shunt.

Indications

Departmental protocols will vary but the overall goal is to image the shunt in its entirety to assess for mechanical causes of shunt failure . The shunt series is performed on both adult and pediatric patients.

Projections

The goal with the shunt projections is, overlap and clear visualization of the shunt, these are not traditionally centered projections.

Frontal skull 
  • AP or PA skull (patient dependent) including the superior aspect of the cervical spine
  • ensuring clear visualization of the shunt in the skull and its path down the cervical region
Lateral cervical spine and skull
  • lateral projection of the cervical spine to include the skull (saving a separate lateral skull) 
  • ensuring clear visualization of the shunt, if this is not achieved an oblique cervical spine may be performed 
Frontal cervical spine
  • frontal view of the cervical spine including a portion of the thoracic vertebrae to ensure overlap with the frontal chest radiograph
Frontal chest
  • PA or AP chest to examine the thoracic portion of the shunt
  • chest exposure factors may make it difficult to appreciate the shunt below the diaphragm, this will be covered in the abdominal radiograph
Frontal abdomen
  • frontal abdomen to image the remaining portion of the shunt
  • any overlap/apparent kinks in the shunt will require a lateral or oblique view to demonstrate the shunt without overlap

Practical points

  • although many patients who present with a suspected shunt failure will receive a head CT, it is not recommended to abstain from performing the skull portion of the series. Patients may have negative CT findings but positive x-ray findings
  • if the shunt is somewhat superimposed on itself in one view, it is recommended to perform additional projections to demonstrate the shunt free of superimposition