Name:
Contralateral interhemispheric transfalcine approach to precuneal glioblastoma: fluorescein guided microsurgical resection and endoscopic microinspection tool
Description:
Contralateral interhemispheric transfalcine approach to precuneal glioblastoma: fluorescein guided microsurgical resection and endoscopic microinspection tool
Thumbnail URL:
https://cadmoremediastorage.blob.core.windows.net/983231a4-2e11-4ba5-935c-fd62ca2cae19/videoscrubberimages/Scrubber_407.jpg
Duration:
T00H08M20S
Embed URL:
https://stream.cadmore.media/player/983231a4-2e11-4ba5-935c-fd62ca2cae19
Content URL:
https://cadmoreoriginalmedia.blob.core.windows.net/983231a4-2e11-4ba5-935c-fd62ca2cae19/21-195.mp4?sv=2019-02-02&sr=c&sig=ocxE6iIV8p%2FvobLsjIeBMKashRFznFu2MS3My1pB7rg%3D&st=2025-10-31T18%3A30%3A38Z&se=2025-10-31T20%3A35%3A38Z&sp=r
Upload Date:
2021-12-08T00:00:00.0000000
Transcript:
Language: EN.
Segment:0 .
[MUSIC PLAYING]
SPEAKER: This video demonstrates a contralateral interhemispheric transfalcine approach to a precuneal glioblastoma with the use of fluorescein- guided surgery and an endoscopic microinspection device. The patient is a 40-year-old man who presented to the emergency department with a 2-day history of headaches and photophobia. Past medical history was significant only for hypertension. He had a nonfocal physical exam, and a CT of his head revealed edema in the deep right parietal lobe.
SPEAKER: His MRI is depicted here and shows a rim-enhancing lesion deep in the subcortical region in the right parietal lobe. Further workup included a CT of his chest, abdomen, and pelvis, which was negative for malignancy. He then underwent a stereotactic brain biopsy, which revealed the diagnosis of high-grade glioma. Other approach options were considered and included a right parietal transcortical or transsulcal approach with monitoring.
SPEAKER: However, given the deep and medial location in the parietal lobe, the closest pial surface was actually medially along the falx. For this reason, a left parietal interhemispheric approach was chosen to minimize transgression of the normal brain. Careful planning with preoperative imaging and neuronavigation to avoid bridging veins is imperative during this approach to prevent complications.
SPEAKER: Fluorescein dye is given intravenously just prior to induction of anesthesia upon entering the room at a dose of 3 mg/kg. The patient is positioned supine with a bump under the right shoulder and the head turned to the left. The head is elevated approximately 45 degrees from the horizontal to allow gravity-assisted retraction of the left hemisphere in order to permit access to the deep tumor in the right side.
SPEAKER: A linear incision is used in the left parietal area, just crossing the midline in order to permit exposure of the sagittal sinus. An oval-shaped hole is placed over the sagittal sinus and a bone flap is elevated in the left parietal area. A piece of Gelfoam is placed over the sagittal sinus to prevent desiccation and thrombosis. The dura is then opened in a C-shaped fashion and the dura is flapped immediately over the sinus and secured with stay sutures.
SPEAKER: Interhemispheric dissection then begins. We use a Rhoton microdisector to free the adhesions along the falx and the medial surface of the parietal lobe. A large venous complex is encountered. And with persistent dissection, we're able to dissect out the individual veins. After further inspection, we can preserve the majority of the complex, needing to sacrifice only one of the veins to prevent a wide enough corridor for tumor resection.
SPEAKER: Telfa patties are lined along the medial surface of the parietal lobe to protect the brain. We then utilize neuronavigation to plan our opening in the falx to permit access to the most superficial component of the tumor. A sharp nerve hook is then utilized to pierce the falx and pull the falx away from the contralateral hemisphere. Monopolar cautery is then transmitted through the nerve hook in order to open the falx.
SPEAKER: Tubing is placed down the axis of the nerve hook in order to prevent thermal injury to the adjacent tissues. Scissors then expand the opening in the falx, and the Telfa patties are advanced to the contralateral side. Rolled cottonoid patties can then be placed laterally in order to further widen the exposure.
SPEAKER: Neuronavigation is then used to plan the cortical entry site, and bipolar cautery is utilized to start a corticotomy. This is then further opened with microscissors and deepened to expose underlying tumor. The yellow 560 filter is then utilized for fluorescent visualization of the tumor.
SPEAKER: The tumor is seen in yellow-green color, and this corresponds with the areas of contrast- enhancing tumor on the MRI scan. Samples are taken for pathologic analysis, and ultrasonic aspiration device is utilized to internally debulk the tumor. The resection continues under white light, and we begin to appreciate the margin between gross tumor and adjacent normal brain on the posterior margin of the cavity.
SPEAKER: A brain ribbon retractor is used intermittently against the falx to help maximize the viewing angles for visualization of the deep-seated tumor. We then proceed with fluorescein- guided resection of the tumor. This fluorescent visualization is particularly useful along the margins of the contrast-enhancing portions of the tumor. In conjunction with neuronavigation, this helps to increase confidence in the discernment at the margins of the tumor cavity.
SPEAKER: We then turn our attention to an area of a relative blind spot superioly and laterally within the resection cavity. This is one area where it is somewhat difficult with microscopic visualization as you are trying to look around a corner with the microscope. Optimal positioning with gravity assistance does help the tumor to fall into the field.
SPEAKER: However, direct visualization at this angle is still somewhat difficult. To help address this, we then bring in an endoscopic microinspection device which is coupled with the microscope. To provide additional views and to look around corners for further tumor resection, this device has a 45- degree viewing angle, which allows us improved visualization of the areas which are not readily apparent with the microscope.
SPEAKER: Final resection of residual areas of tumor and the superior and lateral quadrants of the resection cavity are performed. You can appreciate the improved visualization, which is afforded by the microinspection device compared to traditional microscopic views. The orientation of the microinspection device is then rotated 180 degrees in order to view medially as we insert the device into the resection cavity.
SPEAKER: Completing our 360-degree panoramic inspection of the resection site. The patient did well postoperatively with no neurologic deficits and was discharged home on postoperative day 2. Postoperative MRI depicted here shows an excellent resection of the tumor. There's a small focus of enhancement on the axial images, which is the location of the previous stereotactic biopsy trajectory.
SPEAKER: Diffusion-weighted imaging on the left shows no evidence of ischemia. FLAIR imaging shows expected persistent edema adjacent to the resection cavity and no new edema along the approach trajectory.
