Assessing Shunt patency in Neuclear Medicine

Post on 09-Jan-2017

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DR.YASSER ASIRI R2

SUPERVISED BY:DR.LINA ABDULSAMAD

Cerebrospinal (CSF) shunt scintigraphy

11 year-old male patient known case of cerebral palsy , status post-VP shunt insertion , presented with seizure and vomiting.

18 year-old patient known case of cerebral palsy , VP shunt malfunction, to rule out shunt obstruction

8 year-old with history of shunt placement twice , presented with ? Malfunctioning /under functioning shunt.

What is a shunt patency study?

The shunt patency is a study to determine if cerebrospinal fluid (CSF) is actually flowing through the shunt system (valves and proximal and distal catheters). By injecting a small volume (about 0.3 ml) of a radiotracer into the shunt reservoir, the flow of CSF through the catheters and valve can be measured.

How does it differ from a shunt X-ray or CT Brain ?

While a shunt X-Ray can tell the settings of the shunt and if there is a physical break in the catheters, and CT scan can be used to evaluate ventricle size and the tube position.These studies cannot tell if cerebrospinal fluid (CSF) is actually flowing through the shunt system.

The shunt system consists of a reservoir with a valve placed beneath the soft tissues of the head, a proximal (afferent) tubing line leading from one of the ventricles to the reservoir, and a distal (efferent) tubing line leading from the reservoir to the peritoneal cavity

How is the test performed?

The patient is positioned lying down under the camera system. The hair around the shunt reservoir is clipped or shaved. The reservoir is punctured with a tiny needle. A small amount of the patient’s own CSF is aspirated into a syringe. A small amount (0.3ml) of radiotracer is injected through the needle and flushed with the patient’s own CSF. Pictures are taken every minute for 20 minutes to track the flow of the radiotracer through the shunt system. If no flow is observed the patient is asked to sit up and walk around for 5-10 minutes before more pictures are taken. Rarely, delayed pictures after 1-2 hours may be necessary.

Radiopharmaceutical: (Tc-99m DTPA) [Preferred]

Tc-99m Pertechnetate