Abstract 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.

This video demonstrates microsurgical resection of intramedullary spinal cord metastasis of lung adenocarcinoma. Lung cancer is the predominant cause of rare metastatic intramedullary involvement of the spinal cord.1-4 Because of severe disabilities, these tumors should be considered for treatment with the goal of complete removal to preserve neurological functioning.5-9  Surgical resection improves symptoms, preserves ambulatory status, and increases survival time twice that of nonsurgical treatments.3,8,10 Surgery can be effective in arresting neurological decline.11,12 To our knowledge, this is the first video report of an intramedullary spinal cord metastasis resection.  A 69-yr-old male with history of lung cancer presented with acute onset left arm abduction, forearm flexion, and hand weakness (3/5) and gait disturbance. Cervical spine MRI revealed C4/C5 nonhomogenously enhancing intramedullary tumor measuring 22 × 10 × 7 mm. Sagittal T2-weighted image demonstrated extensive cord edema.  The C4 and C5 laminectomies were performed. Microsurgical techniques were employed.13-15 Metastasis involved the left lateral aspect of the cord with invasion of 2 left dorsal sensory nerve roots, which were resected. Further transection of the dentate ligament relaxed the spinal cord, enabling safer tumor resection. Pial dissection using bipolar forceps, microscissors, and microdissector enabled tumor delivery. Following resection, dural closure was reinforced with previously harvested fat tissue graft to prevent CSF leak.16  Postoperative MRI revealed complete macroscopic resection with improvement of spinal cord swelling. Patient improved his gate and his left arm motor strength was stable. Subsequently, patient received focal adjuvant radiotherapy. Written consent was obtained directly from the patient.

Abstract In this video, we demonstrate epidermoid tumor microsurgical resection of the cerebellopontine angle (CPA) performed by the senior author (K.I.A.). Epidermoid tumors arise from ectoderm trapped within/displaced into the central nervous system. They show predilection for CPA Angle (up to 40%), 4th ventricle, suprasellar region, and spinal cord.1 They are the 3rd most common CPA tumor, comprising approximately 7% of CPA pathology. CPA lesions can produce 5th and 7–12th cranial nerve neuropathies.2 3 4 Recurrent episodes of aseptic meningitis caused by cyst content rupture may occur. Symptoms include fever, meningeal irritation, and hydrocephalus. A 26-year-old female presented with headaches. Head magnetic resonance imaging (MRI) revealed right CPA tumor with brain stem compression (Fig. 1, A–C). There was evidence of restricted diffusion in diffusion-weighted imaging, typical of epidermoid tumor. Surgery was performed in prone position with head turned 25 degrees to the ipsilateral side using retrosigmoid craniotomy.5 Tumor was ventral to the 7th and 8th cranial nerve complexes, between the 5th nerve as well as toward the brainstem. The surgical plan was gross total resection with tumor capsule resection to prevent recurrence.6 (Small residuals can be left behind when capsule is adherent to critical structures.) Tumor was adherent to brain stem perforators which were preserved using meticulous dissection. Cranial nerves and vascular structures were also left intact. We irrigated with antibiotic saline and used perioperative treatment to prevent aseptic meningitis. The pathohistological diagnosis revealed epidermoid tumor cyst. Postoperative MRI revealed complete resection (Fig. 1, D–F). The patient recovered fully and was neurologically intact. The link to the video can be found at: https://youtu.be/LyWl-KZUSGY.

Abstract This video demonstrates microsurgical resection of low-grade (Grade I) thoracic spinal cord astrocytoma. Astrocytomas are the most common pediatric intramedullary tumors and occur secondary to ependymomas in adults.1,2 The treatment goal should be radical gross total resection while preserving neurological function with intraoperative neuromonitoring.2-4 To our knowledge, this is the first video report on microsurgical resection of low-grade spinal cord astrocytoma.  A 58-yr-old female presented with gait disturbances has been featured in this video. A spinal MRI revealed T1/T2 hyperintense intramedullary tumor at T4, suggesting spinal cord astrocytoma versus ependymoma. Dura was opened in the midline and tacked to the surrounding muscle tissue with tacking sutures. The arachnoid was opened separately with microscissors, keeping it intact for closure at the end of surgery. Liga clips were applied to hold the arachnoid to the dura. Myelotomy was done in the midline,5 opening the posterior median sulcus over the length of the tumor and extending proximally and distally a few millimeters beyond the tumor.3,5 The tumor reduction was achieved by coagulation or debulking. Once sufficient debulking was achieved, dissection of the tumor margins toward surrounding cord was performed. Preoperative recording of motor-evoked potentials (MEPs) compared with continuous intraoperative MEPs were essential for preserving the neurological function and quality of life. The intraoperative finding of a clear tumor plane of resection carries positive prognostic significance and reduces the risk of complications.2,3,6  A pathohistological diagnosis showed a low-grade (Grade I) spinal cord astrocytoma (pilocytic). Follow-up MRI showed no sign of tumor or recurrence. The patient recovered fully and was neurologically intact. Written consent was obtained directly from the patient.

SUMMARY – Spinal dumbbell tumors are defined by a narrowing at the point where they penetrate the intervertebral foramina or dura mater, assuming an hourglass or dumbbell shape. Dumbbell-shaped spinal hemangiomas are extremely rare. We describe a dumbbell spinal tumor (epidural cavernous hemangioma) resected by a 2-stage single-sitting combined approach. We also conduct a substantial literature review of the subject. We present a case of a 78-year-old male who was found to have a homogeneously enhancing, dumbbell-shaped, intraspinal, extradural tumor mass extending into the left chest cavity. The tumor was resected with a single-sitting 2-stage posterior technique: a microsurgical approach, followed by endoscopic resection via a thoracoscopic approach. There are several reports in the literature on the combined approach for dumbbell tumors of the spinal cord. Our case is the first to describe 2-stage combined surgery in 1 sitting for dumbbell hemangioma with the patient in the lateral decubitus position for the thoracoscopic part of the surgery; and the use of a fat pad, which was applied in the neuroforamen via the posterior route, as a marker for resection during the transthoracic procedure.