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Chapter 14: Shunt Placement and Marsupialization in Treatment of Hydrocephalus and Quadrigeminal Diverticula 133

the chest or lacerating the skin. Bending the tunneling tube into a but not too tight to lacerate the tubing. The peritoneal catheter
gentle curve helps follow the contour of the body; the tip is directed is secured to the skull by tying the preplaced suture around the
medially as it is passed over the thorax to the neck and then rotated catheter. Alternatively, the shunt is tied to a small titanium
180° to pass over the skull. If excessive force is necessary, a separate screw placed in the skull near the burr‐hole (Figures 14.9
incision in the neck is advisable [2]. The leader is attached to the and 14.10).
distal end of the shunt and the shunt is pulled through the tube to Once in place, the system is checked to ensure that it is flowing,
the abdominal incision. Avoid contact between the shunt and the either spontaneously or with gentle pumping of the reservoir. The
patient’s skin as well as the surgeon’s gloves by using blunt‐tipped or distal catheter is then inserted into the abdomen and secured to
sleeved forceps and clean surgical patties. The ventricular end of the the abdominal muscles with the pursestring suture in a finger-
catheter is held while the tube of the shunt passer is withdrawn trap pattern (Figure 14.10). The scalp and abdominal subcutane-
through the abdominal incision. The valve is attached and irrigated ous tissue are closed with absorbable suture. The skin incisions are
with saline. It is not necessary to test the opening pressure of the closed routinely.
valve because merely handling the valve will affect these measure-
ments [2]. The distal end is placed into the sterile tray from the
shunt package while the ventricular catheter is placed (Figures 14.6
and 14.7).
The trajectory of the ventricular catheter is determined accord-
ing to external landmarks and measurements obtained from preop-
erative imaging. The surgeon will often feel a “pop” or loss of
resistance as the catheter penetrates the ependyma and CSF flows
from the catheter. If the location is uncertain, gently irrigating the
catheter with saline will usually reveal pulsatile flow of CSF. Using a
syringe to vigorously aspirate will only draw brain tissue into the
catheter if it is placed in the parenchyma. A small amount of blood
that clears is not uncommon. With more prolonged bleeding, the
ventricular catheter is gently irrigated with warm saline until the
CSF clears before connecting the shunt so that blood does not
obstruct the valve (Figure 14.8).
The shunt is connected and secured by tying a nonabsorbable
monofilament suture around the catheter over the connector.
The suture is sufficiently tight to avoid subsequent disconnection

Figure 14.9 Anchoring the ventricular catheter and clip to the skull using
the preplaced suture. To prevent dislodgement of the catheter, it is impor-
tant to tie the suture around the catheter itself, not just to the clip.

Figure 14.8 Inserting the ventricular catheter. A metal stylet is placed in the
lumen of the ventricular catheter to assist inserting the catheter into the
ventricle. Figure 14.10 Anchoring the peritoneal catheter to the abdominal muscles.