Jung-Kil Lee

Current surgical results of retrosigmoid approach in extralarge vestibular schwannomas

BACKGROUND Vestibular schwannomas (VS) are common tumors that can be cured; they are reported to comprise 6 approximately 8% of all intracranial tumors. The primary objective in the surgery of extralarge VS is total removal of the tumor mass while preserving the facial nerve. In extralarge tumors, complete excision of the tumor carries a significant risk of injuring the facial nerve and adjacent vital brain structures. The authors are reporting the techniques and results of operation on extralarge VS. METHODS The material consisted of 30 patients during the last 6 years with surgically treated VS that had a maximal extrameatal diameter exceeding 4 cm. Suboccipital craniotomy and tumor removal was performed with patients in the lateral position. Results and complications of the surgical technique will be reviewed. RESULTS Average age of patients was 45.2 years; there was a slight female predominance (1.5:1). Size of the mass ranged from 41 to 70 mm; all were removed by the retrosigmoid transmeatal approach. Peritumoral edema on MRI was seen in 50% (15/30). Total removal was achieved in 73.3% (22/30) with no significant relationship to peritumoral edema. In the cases of total removal, the facial nerve preservation rate was 86.4% (19/22). There was no mortality. Surgical complications were hemorrhage and CSF leakage in 1 case (3%) and 8 cases (26.7%), respectively, but in most of these cases, conservative treatment was adequate. In patients in whom anatomic preservation of the facial nerve was achieved, facial nerve function improved progressively within a year. In all cases except for one with gait disturbance, a good outcome was achieved. CONCLUSIONS Our surgical techniques, including the prediction of facial nerve displacement, not using retractors, and replacement of bone, contributed to good surgical results in a series of extralarge VS.

The efficacy of the synthetic interbody cage and Grafton for anterior cervical fusion.

Study Design. Prospective study of 31 patients who underwent anterior cervical fusion. Objective. To investigate the efficacy of polyetheretherketone (PEEK) cages and demineralized bone matrix (DBM) for anterior cervical discectomy and fusion (ACDF). Summary of Background Data. Although high fusion rates can be achieved with autogenous bone grafts, donor-site morbidity affects the patient’s satisfaction with the surgical outcome. Methods. Thirty-one consecutive patients treated with ACDF using the PEEK cage with DBM (Grafton, Osteotech, Inc., Shrewsbury, NJ) at 42 levels were prospectively evaluated with a minimum of 12-month follow-up (mean: 16 months). Twenty-one patients underwent a single-level ACDF, 9 patients underwent a 2-level ACDF, and 1 patient had a 3-level ACDF. The affected level was C3–C4 in 7 patients; C4–C5 in 9, C5–C6 in 16, and C6–C7 in 10. The neurologic outcomes were evaluated using the VAS score for neck and arm pain and the Japanese Orthopedic Association scoring system for myelopathy at 3, 6, and 12 months. The cervical lordosis and fusion status were assessed on radiographs including flexion/extension radiographs. Results. At 12 months, the radiographs demonstrated grades I, II, and III new bone formation at 1, 13, and 28 levels, respectively. There was a significant improvement in both the neck and arm pain and a significant improvement in the Japanese Orthopedic Association scores at the last follow-up. There was no case with implant-related complications such as cage failure or migration, and no complications associated with the use of Grafton. Conclusion. ACDF using the Solis cage packed with Grafton demonstrated good clinical and radiologic outcomes. The fusion rate was comparable with the published results of the traditional ACDF using tricortical iliac crest grafts. Therefore, the results of this study suggest that the ongoing use of the PEEK cage packed with DBM and autologous bone chips in ACDF is a safe and effective alternative to the gold standard of autologous iliac bone grafts.

Distal anterior choroidal artery aneurysm in a patient with moyamoya disease: case report.

OBJECTIVE AND IMPORTANCE Distal anterior choroidal artery (AChA) aneurysms in moyamoya disease are rare, with few surgically verified reported cases. CLINICAL PRESENTATION We report a rare case of distal AChA aneurysm associated with moyamoya disease in a 48-year-old man who presented with vomiting and severe headache. Computed tomographic scans revealed an intracerebral hematoma in the right temporoparietal lobe and a diffuse intraventricular hemorrhage. INTERVENTION The hematoma was removed via computed tomography-guided stereotactic aspiration and ventricular drainage. Cerebral angiography showed a saccular aneurysm located at the distal branch of the right AChA. By means of magnetic resonance imaging, a small signal void lesion was detected in the periventricular area lateral to the trigone of the right lateral ventricle. The aneurysm was accurately accessed via a parietal cortical incision by use of magnetic resonance imaging-guided stereotactic localization. The aneurysm was successfully resected after undergoing trapping of the parent artery, and when the patient was discharged, he had no evidence of neurological deficit. The aneurysm was histologically verified to be a true aneurysm. CONCLUSION Direct surgery should be considered in cases of ruptured distal AChA aneurysms located in the periventricular or intraventricular regions.

Spinal Cord Injury Produced by Direct Damage During Cervical Transforaminal Epidural Injection

Objective: Cervical transforaminal epidural steroid injection (TFESI) has become a common treatment for cervical radiculopathy. We describe a case of spinal cord injury caused by direct injection of iohexol into the cervical spinal cord during cervical TFESI. Case Report: A 55‐year‐old male suffered from intractable pain in the neck, radiating to his left arm. After undergoing C6‐7 TFESI under fluoroscopic guidance, the patient reported a shooting pain during needle insertion, and developed quadriparesis shortly after contrast injection. The radiological findings of the contrast medium and air bubble within the cord indicated needle penetration and intracord contrast injection. The paresis of his right arm and both legs recovered within 4 hours after the procedure. At 1‐month follow‐up, his left arm paresis had continued to improve. One year after the event, the motor paresis improved except for grasping with the left hand, resulting in a claw hand deformity. Conclusions: This case report draws attention to this very serious complication of cervical TFESI. It is essential to confirm final needle position using both anteroposterior and lateral fluoroscopy before any injection through the needle.

Endovascular embolization of iatrogenic vertebral artery injury during anterior cervical spine surgery: report of two cases and review of the literature.

Study Design. Case description. Objectives. To report 2 cases of vertebral artery injury (VAI) during anterior cervical decompression surgery and review the pertinent medical literature. Summary of Background Data. The incidence of VAI during an anterior surgical approach to the cervical spine is rare but potentially lethal. The spine surgeon should be aware of the detailed surgical anatomy and be prepared to manage an inadvertent injury to the vertebral artery. Methods. In the first case presented, infection was the cause of VAI. During aggressive irrigation and pus drainage, massive bleeding was encountered. For the second case, the vertebral artery was injured during decompression of cervical spondylosis while drilling the neural foramen. Intraoperative direct packing with hemostatic agents provided effective control of hemorrhage. Results. Ten days after surgery, sudden neck swelling and mental deterioration occurred because of rebleeding from a pseudoaneurysm in the first case. In the second case, a pseudoaneurysm was detected by angiography, obtained 4 days after surgery. Both pseudoaneurysms were successfully occluded by an endovascular technique without any neurologic sequelae. Conclusions. In case of bleeding control by hemostatic packing, there remains a risk of delayed hemorrhage from pseudoaneurysm. Postoperative vertebral angiography is helpful to avoid life-threatening complications. Endovascular treatment can be a good alternative in the treatment of VAI.

Thoracic Myelopathy Caused by Ossification of the Ligamentum Flavum

OBJECTIVE Ossification of the ligamentum flavum (OLF) is a rare cause of thoracic myelopathy. The aim of this study was to identify factors associated with the surgical outcome on the basis of preoperative clinical and radiological findings. METHODS Data obtained in 26 patients whot underwent posterior decompression for thoracic myelopathy, caused by thoracic OLF, were analyzed retrospectively. Patient age, duration of symptoms, OLF type, preoperative and postoperative neurological status using the Japanese Orthopedic Association (JOA) scoring system, surgical outcome, and other factors were reviewed. We compared the various factors and postoperative prognosis. All patients had undergone decompressive laminectomy and excision of the OLF. RESULTS Using the JOA score, the functional improvement was excellent in 8 patients, good in 14, fair in 2, and unchanged in 2. A mean preoperative JOA score of 6.65 improved to 8.17 after an average of 27.3 months. According to our analysis, age, gender, duration of symptoms, the involved spinal level, coexisting spinal disorders, associated trauma, intramedullary signal change, and dural adhesions were not related to the surgical outcome. However, the preoperative JOA score and type of OLF were the most important predictors of the surgical outcome. CONCLUSION Early diagnosis and sufficient surgical decompression could improve the functional prognosis for thoracic OLF. The postoperative results were found to be significantly associated with the preoperative severity of myelopathy and type of OLF.

Rutin improves functional outcome via reducing the elevated matrix metalloproteinase-9 level in a photothrombotic focal ischemic model of rats

BACKGROUND Blood-brain barrier (BBB) disruption mediated by proteases plays a pivotal role in neural tissue damage after acute ischemic stroke. In an animal stroke model, the activation of matrix metalloproteinases (MMPs), especially MMP-9, was significantly increased and it showed potential association with blood-brain barrier (BBB) disruption and cerebral edema. Theoretically, it is expected that early blockade of expression and activation of MMP-9 after ischemic stroke provides neuroprotective effects from secondary neural tissue damage. This study was aimed to determine the ability of rutin to influence MMP-9 expression, activity and BBB disruption using a photothrombotic focal ischemic model in rats. METHODS Adult male Sprague-Dawley rats, weighing between 250 and 300 g (aged 8 weeks) received focal cerebral ischemia by photothrombosis using Rose Bengal (RB) and cold light. Injured animals were divided into two groups; one group received 50mg/kg of rutin intraperitoneally, starting 1h after injury and at 12h intervals for 3 days, while animals in the control group received weight-adjusted doses of saline vehicle over the same period. In each group, the expressions and activities of MMP-9 were assessed by Western blot and gelatin zymography at 6, 24, 48, and 72 h after photothrombotic insult. The effects of rutin on BBB disruption and functional outcomes were also determined. RESULTS Western blot and zymographic analysis showed up-regulated MMP-9 expression and activity in the ischemic cortex. The expression and activity of MMP-9 were significantly elevated at 6h after photothrombotic insult, which remained up-regulated for at least until 72 h after injury. In the rutin-treated group, MMP-9 expression and activity were significantly attenuated at 6, 24, and 48 h compared to the control group. Relative to the control group, BBB permeability was significantly reduced in the rutin-treated group. The results of the rotarod test revealed that rutin treatment significantly improved functional outcomes. CONCLUSIONS Rutin treatment starting 1h after injury attenuated BBB disruption during photothrombotic focal ischemia, which was partly, at least, achieved through inhibitory effects on MMP-9 expression and activity. The results of this study suggest that rutin might be useful in clinical trials aimed to improve the outcome of patients suffering from acute ischemic stroke.

Inflammatory aneurysm due to neurocysticercosis.

A 69-year old man presented with a subarachnoid hemorrhage associated with a large intracerebral hematoma in the right temporal lobe. The oblique views of cranio-orbital computerized tomographic angiography (CTA) were suspicious for an aneurysm on a middle cerebral artery branch. At surgery, a cystic mass was found in the Sylvian fissure, associated with an aneurysm on a distal branch of the anterior temporal artery. The aneurysm was not situated at a bifurcation of the artery and was located beneath the cyst. It was secured by trapping. Pathological examination revealed that the cystic lesion was neurocysticercosis and that the aneurysm was inflammatory. We report a ruptured inflammatory aneurysm of a distal branch of the anterior temporal artery associated with neurocysticercosis, and present the histological findings. We believe this is the first report of such an inflammatory aneurysm with histological confirmation.

Kernohan’s notch phenomenon in chronic subdural hematoma: MRI findings

We report two cases of Kernohans notch phenomenon secondary to chronic subdural hematoma detected by MRI. In the first case, the patient was drowsy with an oculomotor palsy and a hemiparesis ipsilateral to the chronic subdural hematoma. MRI in the post-operative period showed no abnormal signal or deformity of the crus cerebri. The neurological signs immediately resolved after trephination. In the second case, the patient was admitted with progressive decrease in their level of consciousness and ipsilateral hemiparesis with the chronic subdural hematoma. MRI on admission revealed an abnormal signal in the contralateral crus cerebri against the chronic subdural hematoma. After surgery, the mental state gradually recovered to normal with some degree of residual hemiparesis. In patients with chronic subdural hematoma, a compressive deformity of the crus cerebri, without abnormal signal on MRI, may predict a better neurological recovery in patients with Kernohans notch phenomenon.

Metastatic Glioblastoma in Cervical Lymph Node after Repeated Craniotomies: Report of a Case with Diagnosis by Fine Needle Aspiration

Head and neck metastasis from glioblastoma is rare event usually seen in patients with previous and repeated surgery. We present the case of a 35 yr-old-female suffering from metastatic glioblastoma in cervical lymph node that was diagnosed by fine needle aspiration. During the last 4 yr, she had four separate craniotomies for the recurrent brain tumors. Cytological diagnosis was made by light microscopy with immunostaining with glial fibrillay acid protein. Chemotherapy with vincristine and procarbazine was performed. The cervical masses were decreased in size and some disappeared while the intracranial glioblastoma continued to grow during chemotherapy. We discuss possible explanations for these different courses after chemotherapy in extraneural metastatic glioblastoma and primary intracranial glioblastoma.