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Spinal ependymomas are the most common intramedullary spinal cord tumors in adults.1-4 They are benign histologically, and maximum safe surgical resection should be pursued with the goal of maintaining neurological integrity.4 Spinal ependymoma resections have been described in the operative video literature, including those using techniques of laminoplasty to prevent postlaminectomy kyphosis.1-3,5 Defining the planes between tumor and normal spinal cord is critical to achieving safe maximum resection.3 This video will illustrate the microsurgical techniques used in the resection of a large spinal cord ependymoma in a patient who presented with progressive lower extremity paraparesis and incontinence and was found to have a large intradural, intramedullary C4-T3 lesion with a rostral glial tumor cyst. The patient consented to surgical intervention. The patient was placed prone in MAYFIELD 3-point pin fixation (Integra LifeSciences, Plainsboro Township, New Jersey). Intraoperative neurophysiological electrodes were placed for somatosensory evoked potentials, motor evoked potentials, and D-wave monitoring of corticospinal tracts.6,7 C3-T4 replacement laminoplasties were performed. A midline dural incision spanning C4-T4 was made. A midline myelotomy preserving the pial venous plexus was performed with a 69 Beaver blade.2 The attachments of the tumor to the normal white matter of the spinal cord were microsurgically defined, coagulated, and divided. Tumor debulking was performed with an ultrasonic aspirator. Once gross total resection was achieved, the pial edges of the spinal cord were reapproximated. The dura was closed in a watertight fashion. The patient recovered from surgery well with preservation of her motor function with a continued T7 sensory level.

The Woven EndoBridge (WEB) device (MicroVention, Aliso Viejo, California) is an intrasaccular flow disruptor used for the treatment of both unruptured and ruptured intracranial aneurysms. WEB has been shown to have 54% complete and 85% adequate aneurysm occlusion rates at 1-yr follow-up.1 Residual and recurrent ruptured aneurysms have been shown to have a higher risk of re-rupture than completely occluded aneurysms.2 With increased utilization of WEB in the United States, optimizing treatment strategies of residual aneurysms previously treated with the WEB device is essential, including surgical clipping.3,4 Here, we present an operative video demonstrating the surgical clip occlusion of previously ruptured middle cerebral artery and anterior communicating artery aneurysms that had been treated with the WEB device and had sizable recurrence on follow-up angiography. Informed consent was obtained from both patients. Lessons learned include the following: (1) the WEB device is highly compressible, unlike coils; (2) proximal WEB marker may interfere with clip closure; (3) no evidence of WEB extrusion into the subarachnoid space; (4) no more scarring than expected in ruptured cases; and (5) clipping is a feasible option for treating WEB recurrent or residual aneurysms.

Orbital metastatic lesions are rare entities1-3 best treated with radical surgical resection with preservation/improvement of neurological and visual function.1-9 Renal cell metastases, in particular, respond less favorably to radiation.9 To our knowledge, an operative video of microsurgical resection of a renal cell carcinoma metastasis to the superior orbital fissure and orbit has not been reported. A patient presented with worsening right eye vision as demonstrated on preoperative visual field testing and found to have a 3 × 1 × 1 cm lesion in the orbit and superior orbital fissure. The patient was placed supine and stealth neuronavigation was used to aid in tumor localization and extension. A cranio-orbital craniotomy and pretemporal exposure2,10,11 were performed to allow extradural dissection of the dura propria off the lateral wall of the cavernous sinus. Right-sided extradural cranial nerves II, III, IV, V1, and V2 were identified, and a high-speed diamond drill was used to perform extradural anterior clinoidectomy and optic nerve decompression. Microsurgical resection of the intraorbital tumor components was performed by the senior author (KIA) to delineate the plane between tumor and periorbita. An oval-shaped dural opening was made to resect the dura involved by tumor, confirmed on histological analysis, followed by closure via dural allograft. The patient's right-sided visual field improved markedly after surgery. Metastatic renal cell carcinoma of the orbit should be resected while preserving and improving preoperative neurological and visual function. The orbitocranial pretemporal approach offers wide visualization to achieve surgical resection. The patient provided written consent and permission to publish her image.

Dumbbell schwannoma of the cervical spine is a known entity,1-5 and should be radically resected with the preservation or improvement of neurological function. However, to our knowledge, an operative video of a C1-C2 cervical dumbbell schwannoma with ventral extension and dorsal spinal cord compression has not been reported previously. This tumor resection video performed by the senior author (KIA) includes details of dural opening, and techniques for microsurgical resection and for postoperative closure to avoid cerebrospinal fluid (CSF) leak and pseudomeningocele formation. Fat grafting was performed through a small paraumbilical incision. The patient was prone in MAYFIELD 3-point pin fixation (Integra LifeSciences, Plainsboro Township, New Jersey). Intraoperative neurophysiological electrodes were placed for somatosensory evoked potential (SSEP) and motor evoked potential (MEP) monitoring. Stealth neuronavigation was used to aid in tumor localization. A small suboccipital craniectomy and C1 laminectomy were performed before opening the dura. Using a microsurgical technique, the dura was opened in the form of the letter "Y." The right-sided dentate ligament was cut to aid in the mobilization of the tumor away from the spinal cord. After dividing the tumor at the dumbbell isthmus, the ventral tumor component was removed, with attention paid to the division of a perforator coming from the vertebral artery. Intraforaminal tumor debulking was performed with a cavitron ultrasonic surgical aspirator (CUSA) and resected. High cervical dumbbell schwannoma should be radically resected while preserving and improving preoperative neurological function. Avoidance of CSF leak and formation of pseudomeningocele should be planned at the beginning, utilizing fascia and fat graft to avoid this feared complication. The patient provided written consent and permission to publish her image.

The brainstem is a less-common location for ependymomas than the spinal cord where they are the most common adult intramedullary tumor.1-18 In this first video case report in the peer-reviewed literature, we demonstrate microsurgical resection of a medulla oblongata ependymoma. There are several case reports of medulla oblongata ependymomas1,3,5,6,13 and a few series of spinal cord ependymomas that included cases of ependymomas of the cervicomedullary junction.9,10 The goal of surgery was to stabilize the preoperative neurological function; favorable outcome is achieved in patients with good preoperative statuses and well-defined tumor boundaries.9 Although gross total resection (GTR) provides the best overall outcome, it is most effective for classic grade II tumors, but not grade I (myxopapillary) and ependymomas, which have a lower GTR rate.14,15 A 55-yr-old patient developed 4-extremity weakness and dysphagia. Pre-/postcontrast magnetic resonance imaging (MRI) revealed centrally located brainstem lesion situated at the lower half of the medulla oblongata. Surgery, performed by the senior author, was performed in the prone position with a small suboccipital craniectomy and C1 posterior arch removal, followed by pia opening and posterior midline myelotomy. Tumor was debulked, dissected from the white matter, and resected. Histology revealed ependymoma (World Health Organization grade II). Postoperative pre-/postcontrast MRI revealed total resection. The patient's neurological deficit completely resolved postoperatively. Written consent was obtained from the patient.