OPERATION PERFORMED: Image-guided stealth stereotactically planned craniotomy and resection of recurrent right frontoparietal glioblastoma multiforme under microdissection technique; dural reconstruction with bovine pericardial (Dura-Guard) allograft cranioplasty; intraoperative somatosensory-evoked potential (SSEP) and electroencephalogram (EEG) monitoring.
PREOPERATIVE DIAGNOSIS: Recurrent right frontoparietal brain tumor.
POSTOPERATIVE DIAGNOSIS: Recurrent right frontoparietal brain tumor.
SURGEON: John Doe, MD
ANESTHESIA: General.
INDICATION FOR OPERATION: The patient is a (XX)-year-old male who has a known glioblastoma multiforme that had been operated on over a year ago. He had had recurrence, treated with gamma radiosurgery. He has been treated on multiple different chemotherapeutic agents and has also undergone fractionated radiation therapy. He has now had recurrent disease with progressive weakness involving the left side of his body, worsening seizures and worsening cranial neuropathies. He was not felt to be a candidate for experimental catheter therapies but was thought to perhaps be a candidate for a new intravenous chemotherapy protocol apparently that he underwent re-resection of the tumor. The risks, benefits, and alternatives of the image-guided stealth stereotactically planned craniotomy surgery were discussed with the patient. The risks described include complete hemiplegia, worsening seizures, recurrent infection, wound dehiscence and poor wound healing, bleeding, pain, permanent disability. The goal of the surgery was to help decrease tumor burden and attempt to potentially improve neurologic function and prolonged survival. It was made clear to the patient that the surgery is not curative. Alternatives to surgery were also discussed. The image-guided stealth stereotactically planned craniotomy procedure was described to him and his family in layman’s terms so that they may understand, and informed consent was obtained for the image-guided stealth stereotactically planned craniotomy.
DESCRIPTION OF THE OPERATION: On the day of surgery, the patient was brought to the preoperative holding area where IV access was obtained for the image-guided stealth stereotactically planned craniotomy. He then underwent high-resolution gadolinium enhancing MRI of the brain using a Stealth protocol. Those images were transferred to the Stealth planning station where there were reviewed by me preoperatively, and a preoperative stereotactic plan was created. The patient was brought back to the operative suite after receiving prophylactic intravenous antibiotics. He was placed on the operating room table in supine position. Dr. (XX) from Vascular Surgery then placed a vena cava filter. After Dr. (XX) was done with his procedure, we then placed the patient’s head in the Mayfield head holder using 3-pin fixation set to a pressure of 70 pounds. We turned him slightly to the left exposing the right frontal and parietal regions. A small bump roll was underneath his shoulder on the right side to help decrease tension of his neck. He was secured to the table after all pressure points were inspected and appropriately padded. A Foley catheter, arterial access, and large bore IV access had already been obtained prior to performing our procedure. This was done prior to Dr. (XX) performing his portion of the surgery. A Foley catheter had also been inserted and TEDs and sequential compression device (SCD) has been applied. SSEP and EEG monitoring leads were placed and baseline series were obtained.
We then registered the fiducials of the Stealth planning station and obtained approximately 2 mm degree of accuracy along our resection cavity in approach. We then made our planned incision using the soft probe, which incorporated the patient’s previous incision extending approximately half an inch on either side of that. We then shaved this area and then sterilely prepped it with 70% alcohol followed by DuraPrep x2. The DuraPrep was allowed to dry. Then, the area was draped in usual fashion. We then used #10 scalpel to incise the skin down to the subcutaneous tissues. We were careful not to overcoagulate the skin edges given his previous radiation and previous surgeries to help maintain a viable skin edge. Cerebellar retractors were placed into the wound exposing the previous craniotomy. The miniplate and miniscrews were removed and then the craniotomy flap was lifted and placed the antibiotic solution. The underlying dura was then opened in a cruciate fashion, and immediately, the brain was noted to be under significant pressure. The patient had received Decadron, was already on seizure medications and also received 25 g of mannitol prior to skin incision.
We then used self-guidance to confirm that we actually were over the area of the tumor. We then used bipolar electrocautery and microsuction to remove some of the tumor burden and also used the CUSA ultrasonic aspirator to internally debulk the tumor, and using microdissection technique, we continued to dissect tumor off along the margins of enhancement based on the image guidance. The tumor was relatively vascular and was very necrotic. Several representative specimens were sent for pathologic diagnosis. The initial frozen sections suggested significant necrosis and cellular debris. Additional specimens were sent for pathologic evaluation. There was hypertrophy of vasculature seen within the tumor, which was controlled with bipolar electrocautery. We proceeded to remove the tumor based on the image guided systems and guidance to the anterior margin, lateral and medial margins, posterior margins and along the depth of the tumor. At the very depth of the tumor, we did enter the ventricle and approximately a 3 mm ventricular bridge was obtained. We confirmed this with image guidance and then repaired the ventricle using a couple of pieces of thrombin-soaked Gelfoam.
Based on the image guidance, we now had exposed and removed tumor along all of the margins and the brain was now very relaxed. Large bulk of tumor was removed and the remaining brain appeared to be edematous without clear evidence of residual necrotic tumor. We then filled the resection cavity with hydrogen peroxide, half strength, cotton balls to obtain meticulous hemostasis. We removed the clips and irrigated it out. We made sure to keep the Gelfoam over the small ventricular bridge. We exchanged that out after meticulous hemostasis was obtained and aligned the resection cavity with a thin layer of Surgicel hemostatic agent. We then proceeded to reconstruct the dura. The dural graft was reconstructed using Dura-Guard and was sewn to the patient’s own dura using a running 4-0 Nurolon suture to obtain watertight closure. This was then covered with DuraGen. We then reapproximated the cranial bone with new titanium miniplates and miniscrews in a separate location to the previous area to originally fixate this area.
We then removed the retractor, copiously irrigated the wound with antibiotic solutions and proceeded to close. The galeal layer was closed with inverted 2-0 Vicryl sutures and the skin closed with a running 3-0 nylon suture. It was covered with antibiotic ointment, Telfa gauge, and tape. The blood loss in the surgery was less than 100 mL. No intraoperative complications occurred. Baseline EEG and SSEP which was normal and its baseline remained unchanged. It did not worsen and waveforms were tractable throughout the time of surgery. At this point, the patient was taken out of the Mayfield head holder, placed back on the hospital gurney. He was allowed to awaken and was taken to the recovery room in stable condition.
