Abstract
Recently ventriculo-peritoneal shunt (V-P shunt) operations are being performed widely in pediatric patients with hydrocephalus. One of the problems in the management of shunt dependent hydrocephalic infants is the evaluation of the patency of the shunt system. This is a report of shuntgraphy and flushing device manometric test to determine the function of the V-P shunts utilizing the Pudenz valve.
A 23 gauge needle is inserted into the Pudenz flushing device. The needle is connected with vinyl tube of 50 cm in length. The ventricular pressure can be measured by this technique when the proximal tube is patent. The vinyl tube is filled with normal saline or cerebrospinal fluid. The fluid slowly moves down to the level of 50-150 mmH2O in cases of normal function of the shunt, but if the distal catheter is obstructed the fluid will not descend and stay in the vinyl tube. Then Conray 60%, or Dimer X 1.0 ml is injected with pressure into the flushing device under fluoroscopic control. In most of the cases the dye flows to distal tube even though the distal shunt system is not well functioning, then 1-4 ml of Conray 60% is added for better visualization and spot films are taken. If reflux of the dye into the lateral ventricle occurs, further injection of contrast material is abandoned.
We have performed this test for 50 V-P shunt implanted hydrocephalic children aged between 3 months and 8 years, who have had 54 shuntgrams in all. The locations and causes of the distal catheter blockage were determined in 34 patients. Several kinds of malfunction of V-P shunt distal catheter were demonstrated.
The findings of shuntgrams are as follows:
1). Capsule formation of the whole distal catheter. 7 cases
2). Blockage of the lower end of the catheter. 6
3). High ventricular pressure without blockage of the shunt system. 4
4). Cyst formation at the lower end of distal catheter. 4
5). Kinking of the distal catheter at the cervical region. 3
6). Disconnection of the distal catheter. 3
7). Localized perfusion of the contrast material in the peritoneal cavity. 3
8). Others. 4
This test has been proved to be simple, safe and reliable in the evaluation of the eventriculo-peritoneal shunt evaluation.
