DATE OF OPERATION: MM/DD/YYYY
PREOPERATIVE DIAGNOSIS: Third ventricular tumor with hydrocephalus.
POSTOPERATIVE DIAGNOSIS: Third ventricular tumor with hydrocephalus.
PROCEDURES PERFORMED:
1. Third ventricular tumor endoscopic biopsy.
2. Third ventriculostomy.
SURGEON: John Doe, MD
ANESTHESIA: General with endotracheal intubation.
TUBES AND DRAINS: Ventricular catheter.
ESTIMATED BLOOD LOSS: 10 mL.
COMPLICATIONS: None.
CONSENT: The risks and benefits of the procedure were discussed at length with the patient who understands and agrees to proceed.
DESCRIPTION OF OPERATION: The patient was brought to the operating room where he was induced under general anesthesia and intubated. He was placed in supine position with the head straight and fixed in the Mayfield crown of thorns. Care was taken to ensure that all pressure points were carefully padded and that the limbs were positioned comfortably. The head was elevated, and the anterior portion of the right side of the head was shaved back to just behind the coronal suture. The sutures in the midline were marked and then a transverse incision was marked in front of the coronal suture for planned small craniotomy. The site was then prepped and draped in the usual sterile fashion.
The skin was incised full thickness with a number 10 blade and then hemostasis maintained with bipolar and Bovie electrocautery. Straight self-retaining retractors were placed to open the scalp incision. A single bur hole was placed in the frontal bone in front of the coronal suture with an AM3 drill bit and then the craniotomy turned with a footplate B1 drill bit on the Midas Rex drill. The craniotomy flap was removed as a single piece, and the dura was then opened in cruciate fashion. A cortical entry point between 2 cortical veins was identified as a safe location for entry, and the surface was cauterized with bipolar cautery. The arachnoid was cut with a #15 blade. An introducer sheath was inserted over an obturator into the lateral ventricle until CSF was encountered in the obturator, which was then removed. The sheath was peeled down to a length of 7 cm, and the straight endoscopic camera was then inserted.
Under endoscopic visualization, we identified the foramen of Monro. There appeared to be an entry through the septum pellucidum that allowed us to visualize the contralateral foramen as well. Entering through the right transverse foramen, we could visualize the anterior third ventricular floor and visualize vascular structures in the posterior aspect and visualize the mamillary bodies. Looking more anteriorly, we recognized the infundibular recess. We then coursed backwards through the third ventricle until a soft, pearly white mass was encountered in the posterior third ventricle. We could not visualize the aqueduct. We presumed, therefore, this represented the tumor. Using irrigation to help clear the field, grasping forceps was inserted, but it could not be well visualized and so the entire apparatus was removed. The straight camera was replaced with a 30-degree camera, and the grasping forceps was inserted. The instrument was then reinserted through the sheath. Once again, we found our landmarks in the anterior third ventricle. A small amount of cortical bleeding was controlled with irrigation. The third ventricle was traversed across a blood clot, which did obscure vision slightly; however, we were able to reidentify the tumor. Several small pieces were grasped and obtained. The tumor was noted to be very soft and friable and did bleed slightly when biopsied. These specimens were sent for frozen section.
At this point, there continued to be a small amount of bleeding, which was controlled with irrigation. Using grasping forceps, we did remove a small part of solid clot. We reidentified the floor of the anterior third ventricle and then performed our third ventriculostomy. Using the grasping forceps and scissors, the floor of the third ventricle was pierced at the thinned translucent portion. This was opened immediately in front of and above the basilar artery bifurcation, which was then visualized through the hole. With that in full visualization, we were able to advance the scope into the hole to widen it and pull back slightly. The scissors were then inserted and used to spread the hole and then cut a small strand of tissue that was binding the hole. This allowed 2 separate openings with good communication of the subarachnoid space. This was clearly visualized as well as the vascular structures below and noted to be clear.
At this point, we returned to the tumor. Once again, there was some clot in the third ventricle that obscured our vision. We coursed backwards but were able to identify some additional abnormal-looking tissue. Due to some blood staining, it was difficult to distinguish tumor from the choroid plexus, but several additional pieces were obtained. After removing a small amount of clot, the tumor became more obvious and additional 2 larger pieces were obtained from the tumor.
At this point, we ensured that we had good hemostasis within the ventricle. It was irrigated with copious amounts of lactated Ringer’s and then the endoscope was removed. The ventricular catheter was then inserted through the peel-away sheath and the sheath removed. The catheter was left in place at approximately 7 cm depth at the cortical margin. CSF did freely flow from the catheter, but was not under high pressure. The catheter was then tunneled to an exit site away from the incision and then capped. The dura was loosely reapproximated with 4-0 Vicryl sutures and then overlaid with a piece of dried Gelfoam. The bone was then thinned on the side of the ventriculostomy catheter to prevent pinching it and then replaced with Synthes craniofacial plates and screws. The galea was then closed with 2-0 Vicryl sutures, and the skin closed with skin staples. The wound was dressed with Telfa dressing, sponge, and paper tape. The patient was removed from the Mayfield crown of thorns and then awakened from anesthesia and extubated without difficulty. The patient was taken to the PACU in stable condition.
