Cisternogram

General

• In-111 DTPA (NOTE: In-111 oxine is what is used for WBC scan, do not confuse)

• Uses

  • CSF leak

  • Hydrocephalus

• Steps

  • Inject radiotracer into lumbar spine

  • Image 2-6 hours after injection, then again 18-24 hours

  • Sometimes very delayed imaging is done at 72 hours

    • Note, if 72 hour imaging is needed then a tracer with a long half life and one that has intrathecal use must be used such as In-111 DTPA

• Normal

  • Tracer visualized in basal cisterns by 1 hour

  • Tracer visualized in sylvian fissure by 6 hours

  • Tracer visualized in cerebral convexities by 12 hours

• Note - if there is intravascular uptake of the In-111 DTPA during administration/LP, the kidneys and bladder will be visualized on the immediate images as the radiopharmaceutical will be cleared by the kidneys.

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