Yoshiaki Takamura

Transdural Indocyanine Green Videography for Superficial Temporal Artery–to–Middle Cerebral Artery Bypass—Technical Note

BACKGROUND Neurosurgical application of indocyanine green (ICG) videography before performing a dural opening, known as transdural ICG videography, has been used during surgery of meningiomas associated with venous sinuses as well as cranial and spinal arteriovenous malformations. However, its use for a superficial temporal artery (STA)-to-middle cerebral artery (MCA) bypass has not been reported. METHODS We performed a retrospective analysis of medical records of patients who underwent transdural ICG videography during STA-MCA bypass performed between January 2012 and March 2015. The primary outcome was visualization of recipient cortical arteries; secondary outcomes were surgical modifications and complications as well as any adverse events associated with transdural ICG videography. RESULTS We analyzed 29 STA-MCA bypass procedures performed in 30 hemispheres with atherosclerotic steno-occlusive disease and found that the proper recipient was identified in 28 hemispheres. Subsequently modified procedures for those were a tailored dural incision and craniotomy correction. No complications associated with ICG administration were encountered; during the postoperative course, transient aphasia was noted in 1 case, chronic subdural hematoma was noted in 1 case, and subdural effusion was noted in 2 cases. CONCLUSIONS Transdural ICG videography for atherosclerotic steno-occlusive disease facilitates modifications during STA-MCA bypass procedures. Recognition of the proper recipient cortical arteries before a dural incision allows the neurosurgeon to perform a tailored dural incision and extension of the bone window, although the contribution to surgical outcome has yet to be determined.

Skull Base Reconstruction Using Multilayer Method for Cerebrospinal Fluid Leakage During Endonasal Endoscopic Surgery for Tumor Removal

Objective: A tight skull base reconstruction is important for patients undergoing endonasal endoscopic surgery. We report here details of our skull base reconstruction procedure using a multilayer method for intraoperative cerebrospinal fluid (CSF) leakage occurring during endonasal endoscopic surgery for tumor removal. Methods: To achieve a successful tight repair in cases with high-flow CSF leakage, we have adopted a multilayer method using inlay and onlay fascia, fat from abdomen, and rigid hard bone from nasal septal bone to stop CSF pulsation, as well as a nasoseptal flap to cover the skull base defect. Furthermore, a sinus balloon is inserted into the sphenoid sinus for a few days to secure the above listed materials keep them from falling. Results: Of the 144 patients who underwent endonasal endoscopic surgery performed from November 2008 to March 2015 at our institution, 48 had CSF leakage. The mean age of those patients was 54.9 years old and 41 had a pituitary adenoma, 5 at Rathke’s cleft cyst, 1 a chordoma, and 1 a malignant lymphoma. The mean tumor size was 29.1 mm. Esposito grade 1, 2, and 3 CSF leakage was seen in 18, 16, and 14 cases, respectively. Grade 3 cases had significantly larger tumors as compared to grade 1. There were no differences among the groups regarding the amount of gross total removal. Utilizing a multilayer method in 14 cases with high-flow CSF leakage during the operation, we were able to achieve a tight skull base reconstruction in all cases with no late CSF leakage. Conclusion: Skull base reconstruction with a multilayer method was effective to achieve a tight repair and stop intraoperative high-flow CSF leakage.

Glioblastoma Mimicking Subarachnoid Hemorrhage of Unknown Etiology: A Case Report

BACKGROUND Glioblastoma is the most common primary malignant tumor of the brain. Common radiologic findings using initial computed tomography (CT) reveal an intra-axial lesion with perifocal edema. Here, we present a rare case of diffuse subarachnoid hemorrhage (SAH) detected on an initial CT image in a patient without intracranial aneurysm in whom the final diagnosis was glioblastoma. CASE DESCRIPTION We report the rare case of a 57-year-old man with glioblastoma in the right temporal lobe who presented with a sudden onset of disturbance of consciousness as an initial manifestation. Initial CT of the head revealed a diffuse SAH. Digital subtraction angiography revealed no cerebral aneurysm or dissection of intracranial arteries. The patient was treated for SAH of unknown etiology with conservative therapy, and a repeat digital subtraction angiography demonstrated no vascular disease. Eventually, he was discharged without any neurologic deficit. A follow-up CT of the brain revealed an intracerebral hemorrhage in the right temporal lobe, and magnetic resonance imaging revealed a ring enhancing lesion in the anterior section of right temporal lobe. The patient was transferred to our department, where he underwent surgical resection, and a pathologic diagnosis of glioblastoma was made. CONCLUSIONS We present a rare case of glioblastoma mimicking SAH of unknown etiology and recommend including glioblastoma in the differential diagnosis of SAH of unknown etiology.

Central Herniation Induced by Craniotomy Prompting Air Replacement for Subdural Fluid Collection Due to Cerebrospinal Fluid Hypovolemia

BACKGROUND Chronic subdural hematoma (CSDH) often occurs in association with cerebrospinal fluid (CSF) hypovolemia. Many cases with CSDH due to CSF hypovolemia and treated by burr hole surgery have been reported to present with paradoxical deterioration. However, the mechanisms and pathology of deterioration after surgery for CSDH due to CSF hypovolemia remain obscure. CASE DESCRIPTION We report herein a 62-year-old man with gait disturbance due to subdural fluid collection (SDFC) who underwent burr hole irrigation and additional craniotomy, in which postoperative deterioration resulted from rapidly progressing central herniation with a large amount of air accumulation. Epidural blood patch with saline infusion in the thoracic spine finally resolved central herniation. CONCLUSION SDFC deteriorating after surgery has never been reported. SDFC has communication with CSF differing from mature CSDH composed of closed cavity surrounded by neomembrane. Under situations of CSF hypovolemia due to spinal dural tear, opening the cranium can prompt air replacement in the CSF space, which might represent a substantial risk for central herniation caused by a rapid loss of buoyancy force.

Risk of brain herniation after craniotomy with lumbar spinal drainage: a propensity score analysis

OBJECTIVELumbar spinal drainage (LSD) during neurosurgery can have an important effect by facilitating a smooth procedure when needed. However, LSD is quite invasive, and the pathology of brain herniation associated with LSD has become known recently. The objective of this study was to determine the risk of postoperative brain herniation after craniotomy with LSD in neurosurgery overall.METHODSIncluded were 239 patients who underwent craniotomy with LSD for various types of neurological diseases between January 2007 and December 2016. The authors performed propensity score matching to establish a proper control group taken from among 1424 patients who underwent craniotomy and met the inclusion criteria during the same period. The incidences of postoperative brain herniation between the patients who underwent craniotomy with LSD (group A, n = 239) and the matched patients who underwent craniotomy without LSD (group B, n = 239) were compared.RESULTSBrain herniation was observed in 24 patients in group A and 8 patients in group B (OR 3.21, 95% CI 1.36-8.46, p = 0.005), but the rate of favorable outcomes was higher in group A (OR 1.79, 95% CI 1.18-2.76, p = 0.005). Of the 24 patients, 18 had uncal herniation, 5 had central herniation, and 1 had uncal and subfalcine herniation; 8 patients with other than subarachnoid hemorrhage were included. Significant differences in the rates of deep approach (OR 5.12, 95% CI 1.8-14.5, p = 0.002) and temporal craniotomy (OR 10.2, 95% CI 2.3-44.8, p = 0.002) were found between the 2 subgroups (those with and those without herniation) in group A. In 5 patients, brain herniation proceeded even after external decompression (ED). Cox regression analysis revealed that the risk of brain herniation related to LSD increased with ED (hazard ratio 3.326, 95% CI 1.491-7.422, p < 0.001). Among all 1424 patients, ED resulted in progression or deterioration of brain herniation more frequently in those who underwent LSD than it did in those who did not undergo LSD (OR 9.127, 95% CI 1.82-62.1, p = 0.004).CONCLUSIONSBrain herniation downward to the tentorial hiatus is more likely to occur after craniotomy with LSD than after craniotomy without LSD. Using a deep approach and craniotomy involving the temporal areas are risk factors for brain herniation related to LSD. Additional ED would aggravate brain herniation after LSD. The risk of brain herniation after placement of a lumbar spinal drain during neurosurgery must be considered even when LSD is essential.

Novel Human NK Cell Line Carrying CAR Targeting EGFRvIII Induces Antitumor Effects in Glioblastoma Cells

Background/Aim: Natural killer (NK) cells are considered potential antitumor effector cells. The aim of this study was to establish a novel type of a chimeric antigen receptor (CAR) NK cell line (CAR-KHYG-1) specific for epidermal growth factor receptor variant III (EGFRvIII)-expressing tumors and investigate the anti-tumor activity of EGFRvIII-specific-CAR-KHYG-1 (EvCAR-KHYG-1). Materials and Methods: EvCAR-KHYG-1 was established by self-inactivated lentiviral-based transduction of the EvCAR gene and magnetic bead-based purification of EvCAR-expressing NK cells. The anti-tumor effects of EvCAR-KHYG-1 were evaluated using growth inhibition and apoptosis detection assays in glioblastoma (GBM) cell lines (EGFRvIII-expressing and non-expressing U87MG). Results: The findings demonstrated that EvCAR-KHYG-1 inhibited GBM cell-growth via apoptosis in an EGFRvIII-expressing specific manner. Conclusion: This is the first study to establish a CAR NK cell line based on the human NK cell line KHYG-1. Therapy with EvCAR-KHYG-1 may be an effective treatment option for GBM patients.

Thoracic ossification of ligamentum flavum manifesting holocord syringomyelia: case report

It has been reported that syringomyelia is rarely associated with degenerative spinal disorders, but the case of holocord syringomyelia is never reported. We here present a case of a 59-year-old woman with right shoulder pain, dysesthesia of the right hand, and gait disturbance. Radiographically, examinations of the spine demonstrated holocord syringomyelia with ossification of ligamentum flavum at T2/3 level. Holocord syringomyelia was reduced remarkably after posterior decompression at the T2/3 level, and her symptoms also improved. We speculated that holocord syringomyelia might have developed due to craniospinal pressure dissociation caused by focal compression of dural sac from extradural degenerative change.

Reply to “Surgical treatment of posterior inferior cerebellar artery aneurysms”

Dear Editor, We thank Dr. Wang and Dr. Sui for their comments on our article [3]. The authors suggest that some issues remained regarding the diagnosis, selected endovascular treatment option, and necessity of postoperative long-term follow-up of the lesion in our surgical treatment of a posterior inferior cerebellar artery (PICA) aneurysm. We would like to answer those issues by adding some images. As the authors pointed out, high-resolution magnetic resonance imaging (MRI) including basi-parallel anatomical scanning could help diagnose dissecting aneurysms more precisely. We also mentioned the importance of the MRI’s ability to depict direct images of the vessel walls and intramural thrombi in the discussion part of our article. For want of space, we had to omit MRIs showing a pseudo-lumen, which retrospectively suggest the dissection of this lesion (Fig. 1). The clinical course and steady growth in a relatively short time period were consistent with the nature of a dissecting aneurysm. Even though the patient did not present with headaches, the recurrent vertigo attacks with disequilibrium completely disappeared after surgery, a symptom thought to stem from the compression of the vestibular nerve by a rapidly growing aneurysm [4]. Additionally, we came to the diagnosis of a dissecting aneurysm because of the findings of a young adult without a past history of symptoms associated with atherosclerosis such as hypertension and diabetes mellitus, no evidence of a family history, no characteristic physical findings of collagen diseases, and the absence of similar changes in other intracranial arteries. The ideal treatment for VA dissection involving the PICA is trapping or proximal clipping with revascularization. However, trapping the lesion will not prevent a partial medullary infarction in the case of a proximal PICA aneurysm with incorporated perforators, even after revascularization has occurred. Proximal clipping would increase the risk of perforator occlusion by extending thrombosis because of termination of the PICA. The wrap-clip technique is one alternative that does not increase the risk of perforating artery occlusion, preserves the original antegrade blood flow, and prevents fusiform aneurysm growth. Although this case was treated by open surgery at the time, endovascular stent-assisted coil embolization might be a better treatment option for wide-necked PICA aneurysms. As the authors mentioned, retrograde stenting through the contralateral VA may provide an easy access to the PICA with an acute angle between the PICA origin and the VA [1]. In this case, however, the left VA was hypoplastic, and its caliber was too small to provide an access route for the introduction of a microcatheter (Fig. 2). In contrast, the ipsilateral VA had a mild acute angle and could have been used as an access route to the right PICA for the deployment of a LVIS Jr. stent, spanning from the proximal PICA to just about the orifice of the PICA. However, we would not be able to guarantee no future recurrences of this lesion regardless of the chosen treatment. * Yasushi Motoyama myasushi@naramed-u.ac.jp

Relationship between dyslipidemia and vascular repair after cervical artery dissection

In some cases of cervical artery dissection, vascular repair subsequently occurs at the stenotic or occluded sites. The factors responsible for this type of vascular repair remain unknown, but some reports from in vitro and animal models suggest that it is related to lipid metabolism.

Penetration of the Optic Nerve by an Unruptured Internal Carotid Artery- Ophthalmic Artery Aneurysm: Case Report

Internal Carotid Artery (ICA)-ophthalmic artery aneurysms are relatively rare aneurysms, constitute 0.3% to 1% of intracranial aneurysms and 0.9% to 6.5% of aneurysms of the ICA. Including them, large and giant aneurysms developing around the optic nerve sometimes press it and make it thin, but rarely penetrate it. There have been very few reports that they could predict the ICA-ophthalmic artery aneurysm penetrated the optic nerve with preoperative Magnetic Resonance Imaging (MRI), and it is very useful. We present a case that we could predict penetration of the optic nerve by an ICA-ophthalmic artery aneurysm before the operation, and could confirm it in the operation.