Effectiveness of Keyhole Clipping of Unruptured Intracranial Aneurysms Detected by "Brain Dock" in Healthy Japanese Adults

In Japan, brain docking has enhanced the detection of unruptured intracranial aneurysms in healthy adults. At our institution, surgical clipping is the first-line treatment for unruptured intracranial aneurysms (UIA). In this study, the differences in neurological and radiological outcomes, as well as cognitive and psychological results, between standard clipping and keyhole clipping for these aneurysms detected via brain docking were evaluated. The study included 131 aneurysms detected via "brain dock." Of these, 65 were treated with keyhole clipping surgery (keyhole clipping group), and 66 were treated with standard clipping surgery (standard clipping group). Evaluations at 3 months included the National Institutes of Health Stroke Scale, modified Rankin Scale, Mini-Mental State Examination, Hasegawa's Dementia Scale-revised, Beck Depression Inventory, Hamilton Rating Scale for Depression, and radiological abnormalities. The mean operative time and postoperative hospitalization period were significantly shorter in the keyhole clipping group than in the standard clipping group (p < 0.001). Between the groups, no significant differences in postoperative neurological complications or radiological abnormalities were found. The keyhole clipping group demonstrated slightly but significantly better Beck Depression Inventory and Hamilton Rating Scale for Depression scores than the standard clipping group (Beck Depression Inventory, p = 0.046; Hamilton Rating Scale for Depression, p < 0.01). Both the Beck Depression Inventory and Hamilton Rating Scale for Depression scores at 3 months were significantly enhanced (p < 0.001) in the keyhole clipping group. These findings propose that keyhole clipping could be considered a new therapeutic option for small UIA detected via brain docking.

Carotid Artery Stenting via Radial Access with Modified Flow Reversal Method: Case Series

OBJECTIVE

Neuroendovascular treatment via transradial access (TRA) has gained popularity as a minimally invasive technique. However, the flow reversal (FR) system, reported useful in carotid artery stenting (CAS), cannot be applied via TRA because it requires an access route of more than 8 F. Herein, we report the utility of a modified FR system applied via TRA using a sheathless 8-F balloon guide catheter and a 2.6-F balloon catheter.

METHODS

In a retrospective analysis of a single-center consecutive case series, patients with CAS and vulnerable plaques who were treated with CAS via TRA using a modified FR system from June 2022 to August 2022 were examined. High-intensity spots were assessed on postprocedural diffusion-weighted magnetic resonance images. Puncture site complications at discharge and cardiovascular events for 1 year after CAS were also evaluated.

RESULTS

Ten patients were included in this study. There were no high-intensity spots on diffusion-weighted magnetic resonance images after CAS. No procedure-related complications, including radial artery occlusion or cardiovascular events, were observed.

CONCLUSIONS

This study suggests that CAS with FR using our modified system is feasible via TRA and may be an effective technique with a low rate of vascular complications.

KLC1-ROS1 Fusion Exerts Oncogenic Properties of Glioma Cells via Specific Activation of JAK-STAT Pathway

Here, we investigated the detailed molecular oncogenic mechanisms of a novel receptor tyrosine kinase (RTK) fusion, KLC1-ROS1, with an adapter molecule, KLC1, and an RTK, ROS1, discovered in pediatric glioma, and we explored a novel therapeutic target for glioma that possesses oncogenic RTK fusion. When wild-type ROS1 and KLC1-ROS1 fusions were stably expressed in the human glioma cell lines A172 and U343MG, immunoblotting revealed that KLC1-ROS1 fusion specifically activated the JAK2-STAT3 pathway, a major RTK downstream signaling pathway, when compared with wild-type ROS1. Immunoprecipitation of the fractionated cell lysates revealed a more abundant association of the KLC1-ROS1 fusion with JAK2 than that observed for wild-type ROS1 in the cytosolic fraction. A mutagenesis study of the KLC1-ROS1 fusion protein demonstrated the fundamental roles of both the KLC1 and ROS1 domains in the constitutive activation of KLC1-ROS1 fusion. Additionally, in vitro assays demonstrated that KLC1-ROS1 fusion upregulated cell proliferation, invasion, and chemoresistance when compared to wild-type ROS1. Combination treatment with the chemotherapeutic agent temozolomide and an inhibitor of ROS1, JAK2, or a downstream target of STAT3, demonstrated antitumor effects against KLC1-ROS1 fusion-expressing glioma cells. Our results demonstrate that KLC1-ROS1 fusion exerts oncogenic activity through serum-independent constitutive activation, resulting in specific activation of the JAK-STAT pathway. Our data suggested that molecules other than RTKs may serve as novel therapeutic targets for RTK fusion in gliomas.

Hyperbaric hydrogen therapy improves secondary brain injury after head trauma

Background

The pathophysiology of traumatic brain injury (TBI) is caused by the initial physical damage and by the subsequent biochemical damage (secondary brain injury). Oxidative stress is deeply involved in secondary brain injury, so molecular hydrogen therapy may be effective for TBI. Hydrogen gas shows the optimal effect at concentrations of 2% or higher, but can only be used up to 1.3% in the form of a gas cylinder mixed with oxygen gas, which may not be sufficiently effective. The partial pressure of hydrogen increases in proportion to the pressure, so hyperbaric hydrogen therapy (HBH2) is more effective than that at atmospheric pressure.

Methods

A total of 120 mice were divided into three groups: TBI + non-treatment group (TBI group; n = 40), TBI + HBH2 group (n = 40), and non-TBI + non-treatment group (sham group; n = 40). The TBI and TBI + HBH2 groups were subjected to moderate cerebral contusion induced by controlled cortical impact. The TBI + HBH2 group received hyperbaric hydrogen therapy at 2 atmospheres for 90 minutes, at 30 minutes after TBI. Brain edema, neuronal cell loss in the injured hippocampus, neurological function, and cognitive function were evaluated.

Results

The TBI + HBH2 group showed significantly less cerebral edema (p ≺ 0.05). Residual hippocampal neurons were significantly more numerous in the TBI + HBH2 group on day 28 (p ≺ 0.05). Neurological score and behavioral tests showed that the TBI + HBH2 group had significantly reduced hyperactivity on day 14 (p ≺ 0.01).

Conclusion

Hyperbaric hydrogen therapy may be effective for posttraumatic secondary brain injury.

Feasibility and Challenges of Transradial Approach in Neuroendovascular Therapy: A Retrospective Observational Study

Objective

Transradial approach (TRA) is increasingly used as a viable alternative to the traditional transfemoral approach (TFA) in neuroendovascular therapy (NET) owing to its potential anatomical benefits and lower puncture-site complication rates. However, the real-world challenges of implementing TRA-NET have not been thoroughly studied, particularly those related to guide catheter (GC) placement. In this study, we aimed to explore the feasibility and challenges of TRA-NET, with a specific focus on GC placement.

Methods

This retrospective observational study included patients who underwent NET at our institution between December 2019 and May 2022. Procedural success was defined as the successful placement of a GC in the target vessel. Cases in which a Simmons-shaped GC was used or the approach was changed to TFA were classified as difficult. Safety was assessed based on the rate of severe puncture-site complications requiring either blood transfusion or surgical intervention.

Results

Among the 310 patients who underwent NET during the study period, 222 (71.6%) with a median age of 74 years were selected for TRA-NET. The target vessel was in the left anterior circulation (LtAC) in 101 (45.5%) patients, and 8-F GCs were the most frequently used (40.1%). TRA-NET achieved a 95.0% success rate, with a switch to TFA required in 5.0% of the cases. Procedural challenges occurred in 42 (18.9%) patients, primarily in those with LtAC lesions. Specifically, a type III aortic arch (p <0.0001) and age ≥80 years (p = 0.01) were significantly associated with procedural difficulties. Radial artery evaluation was confirmed in 66 cases (29.7%), revealing one instance (1.5%) of radial artery occlusion. No severe puncture-site complications were observed.

Conclusion

TRA-NET may provide substantial therapeutic benefits without significant limitations in device use. However, it may be challenging, particularly in older patients and those with a type III aortic arch with LtAC lesions. Consequently, careful selection of the approach route is imperative.

Validation of Efficacy and Safety of TachoSil ® Tissue Sealant for Vessel Transposition in Microvascular Decompression

BACKGROUND AND OBJECTIVES

Use of TachoSil ® as the transposition material of microvascular decompression (MVD) for hemifacial spasm (HFS) and trigeminal neuralgia (TN) is easy and safe to perform, but the efficacy and safety of this technique are unknown. This study attempted to validate the efficacy and safety of TachoSil ® as a transposition material of MVD.

METHODS

A retrospective study of the surgical results and complications of 63 patients (35 HFS and 28 TN) treated by the TachoSil ® technique between January 2011 and December 2021 was conducted. The efficacy of the treatment was evaluated by Kaplan-Meier survival analysis. Magnetic resonance imaging follow-up study was performed to detect any adverse events including a mass formation.

RESULTS

The rate of complete disappearance of HFS was 91.4% at 1 year and estimated to be 85.7% after a 10-year follow-up. The rate of no pain without medication for TN was 85.4% at 1 year and estimated to be 69.0% after a 9-year follow-up. These surgical results are comparable with those previously reported. Flaking of TachoSil ® releasing the offending artery was only recognized in one case (1.6%). Therefore, TachoSil ® can be considered as an effective transposition material for MVD. TachoSil ® did not increase the rate of acute and subacute adverse events such as inflammation and delayed facial palsy. Magnetic resonance imaging follow-up identified no abnormalities including mass that suggested granuloma formation.

CONCLUSION

The efficacy of the TachoSil ® technique for HFS and TN and the reliability of TachoSil ® as an adhesive material in MVD were verified. No adverse events associated with TachoSil ® use in MVD were found. We conclude that the TachoSil ® technique has relatively long efficacy and safety for MVD.

Cadaver investigation of the usefulness of the transstyloid diaphragm approach for high-position plaque carotid endarterectomy

OBJECTIVES

Patients sometimes present with high cervical internal carotid artery (ICA) stenosis. This study demonstrates the usefulness of the transstyloid approach to expose the distal ICA by dissection of the styloid diaphragm covering the distal cervical ICA for carotid endarterectomy (CEA). In particular, the possible exposure length achieved by this approach was investigated using cadaveric heads.

METHODS

The procedure of the transstyloid diaphragm approach was confirmed in 10 cadaveric heads (20 sides). After the carotid triangle was opened, both the posterior belly of the digastric muscle (PBDM) and the stylohyoid muscle could be divided. Then, the carotid sheath was dissected, and the glossopharyngeal nerve was identified crossing over the distal ICA. The revealed length of the ICA was measured with or without dissection of both the PBDM and the stylohyoid muscle. The specimens were dissected under the surgical microscope.

RESULTS

The transstyloid diaphragm approach was achieved successfully in all specimens. The revealed lengths of the ICA with and without dissection of the styloid diaphragm were 53.7 ± 5.9 mm and 38.8 ± 2.9 mm (mean ± standard deviation), respectively. Therefore, the revealed length of the distal ICA was 14.9 ± 4.5 mm greater using the transstyloid diaphragm approach compared to the regular CEA approach.

CONCLUSIONS

More of the ICA can be revealed by dissection of both the PBDM and the stylohyoid muscle. The transstyloid diaphragm approach might be helpful to reveal the distal ICA in cases of high cervical ICA stenosis.

The Short-Term Outcome of Middle Meningeal Artery Embolization for Chronic Subdural Hematoma with Mild Symptom: Case Series

OBJECTIVE

A few reports have demonstrated the efficacy of middle meningeal artery embolization (MMAE) alone for mildly symptomatic chronic subdural hematoma (CSDH); however, the clinical course in the early posttreatment period remains unclear. The purpose of this study was to analyze the short-term outcomes of this technique at our center.

METHODS

This study was based on a retrospective analysis of a single-center consecutive case series. Patients with mildly symptomatic CSDH treated with MMAE alone between July 2020 and June 2022 were examined. Neurological examinations and head computed tomography scans were performed before treatment and 1, 7, 14, and 28 days after treatment. The clinical course of the patients was analyzed. In particular, symptom improvement within 1 week from treatment or rescue evacuation and the factors associated were evaluated.

RESULTS

Fifteen patients were included in this study. No procedure-related complications occurred. Partial or complete recovery within the first week from treatment was observed in 10 cases (66.7%), and the symptoms resolved completely in a median of 26 (6.5-33.5) days. Rescue evacuation was needed in 3 cases (20.0%). The hematoma volume and midline shift gradually decreased from baseline, with a significant improvement within the first week (P = 0.030 and 0.0032, respectively).

CONCLUSIONS

MMAE alone provides relatively early improvement in cases of mildly symptomatic CSDH and may be a potential alternative to surgical evacuation or medical therapy.

Prophylactic intraventricular piping method prevents entrapped temporal horn after removal of ventricle trigone meningioma: technical note

BACKGROUND

Entrapped temporal horn (ETH) is one of the critical complications after tumor removal in the lateral ventricle trigone that sometimes becomes life-threatening.

OBJECTIVE

To develop a novel intraoperative method of prophylactic intraventricular piping (PIP) just after tumor removal to prevent ETH.

METHODS

Three patients with meningiomas in the lateral ventricle trigone were treated by a novel intraoperative method of PIP just after tumor removal to prevent ETH. Silicone catheters normally used as ventricular drainage catheters were cut to 5-6 cm length and inserted into the tumor cavity to ensure communication between the temporal horn and the atrium or the body of the lateral ventricle through the piping straddling the trigone.

RESULTS

None of our patients developed ETH during the follow-up period without complications caused by the tube placement.

CONCLUSIONS

PIP might be beneficial to prevent ETH because constant osmotic pressure and constant cerebrospinal fluid pulse wave transmission are maintained between each compartment of the lateral ventricle.

Superior Effectiveness of a Newly Developed Nonadherent Polyurethane-Coated Surgical Patty for Hemostasis

Background:

Cotton patty is usually used to aspirate blood and cerebrospinal fluid to maintain a dry field. However, the cotton patty easily adheres to the vessels by capillary action, especially in combination with hemostat. Therefore, re-bleeding may be induced by removal of the cotton patty stuck to the vessel despite initial control of the bleeding.

Methods:

We have developed a new cotton patty (Non-Stina X^®, Hakujuji, Co., Ltd., Tokyo, Japan) which does not adhere to the vessels. The newly developed cotton patty is made of 100% cotton, with only the contact surface coated with polyurethane film which prevents capillary action. The coated side includes many holes to allow aspiration from both sides.

Results:

The characteristics of four different surgical patties including our new patty which are available for surgical use in Japan were investigated. Transverse sections of four different surgical patties were investigated by light microscopy (magnification ×150). Our new cotton patty did not show any fluffing on the polyurethane-coated surface. However, other surgical patties showed some fluffing on their surfaces. The friction coefficients of four different surgical patties were investigated. Our new cotton patty had the lowest of the four neurosurgical patties. We confirmed the nonadherent characteristic using with hemostats of gelatinous sponge or fibrin glue-soaked oxidized cellulose cotton during hemostasis in neurosurgical procedures. The polyurethane-coated cotton patty could be removed easily from the hemostats without re-bleeding.

Conclusions:

The newly developed polyurethane-coated cotton patty is more effective for bleeding control from vessels with several types of hemostat due to the nonadherent characteristics.

Intravenous Hydrogen Therapy With Intracisternal Magnesium Sulfate Infusion in Severe Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

Poor-grade subarachnoid hemorrhage still has a poor prognosis. This randomized controlled clinical trial evaluated intracisternal magnesium sulfate infusion combined with intravenous hydrogen therapy in patients with poor-grade subarachnoid hemorrhage.

METHODS

Thirty-seven patients with poor-grade subarachnoid hemorrhage were randomized to Mg+H₂, Mg, and control groups. Mg and Mg+H₂ groups received intracisternal magnesium sulfate infusion (2.5 mmol/L) at 20 mL/h for 14 days. Mg+H₂ group also received intravenous hydrogen-rich solution infusion for 14 days. Primary outcome measures were occurrence of delayed cerebral ischemia and cerebral vasospasm. Secondary outcome measures were modified Rankin Scale and Karnofsky performance status at 3 and 12 months, Barthel index at 12 months, and serum and cerebrospinal fluid malondialdehyde and neuron-specific enolase.

RESULTS

Serum neuron-specific enolase levels were significantly lower in the Mg+H₂ group from days 3 to 14 than in the control group. Cerebrospinal fluid neuron-specific enolase levels were also significantly lower in the Mg+H₂ group from days 3 to 7 than in the control group. Incidences of cerebral vasospasm and delayed cerebral ischemia were significantly higher in the control group than in other groups. Modified Rankin Scale and Karnofsky performance status did not significantly differ between the three groups at 3 months. Modified Rankin Scale scores 0 to 2 were more common in the Mg and Mg+H₂ groups at 1 year. Barthel index was higher in the Mg+H₂ group than in the control group.

CONCLUSIONS

Intracisternal magnesium sulfate infusion started immediately after surgery reduces the incidence of cerebral vasospasm and delayed cerebral ischemia and improves clinical outcomes without complications in patients with poor-grade subarachnoid hemorrhage. Intracisternal magnesium sulfate infusion combined with intravenous hydrogen therapy decreases serum malondialdehyde and neuron-specific enolase and improves Barthel index, indicating hydrogen has additional effects. Registration: URL: https://www.umin.ac.jp/ctr/index.htm. Unique identifier: UMIN000014696.

Ruptured Dissecting Aneurysm of the Carotid Artery 12 Years after Gamma Knife Therapy for Pituitary Adenoma

Objective

We report a rare case of carotid artery dissection leading to fatal epistaxis 12 years after Gamma knife surgery.

Case Presentation

A 65-year-old woman underwent Gamma knife surgery for remnant pituitary adenoma adjacent to the left cavernous sinus after transsphenoidal tumor removal. After 12 years, she developed repetitive critical hematemesis subsequent to cardiopulmonary arrest, and a dissecting aneurysm of the cavernous segment of the left internal carotid artery (ICA) was identified by cerebral angiography after resuscitation and massive blood transfusion. Effective hemostasis was confirmed by endovascular embolization to occlude the affected carotid artery. She was transferred to a rehabilitation facility 1 month after onset.

Conclusion

The etiology of this pathology may have been a collapsed vasa vasorum or fibrosis of adventitia on the carotid wall adjacent to the irradiated site. We need to suspect this rare but serious pathology in patients with histories of irradiation of the cavernous region who develop massive hematemesis of unknown origin.

[Hemifacial Spasm Caused by Vertebral Artery Fusiform Aneurysm and the Anterior Inferior Cerebellar Artery]

We report a case of hemifacial spasm in which the root exit zone(REZ)of the facial nerve was compressed by both the vertebral artery(VA)aneurysm and the anterior interior cerebellar artery(AICA). A 60-year-old female had suffered left hemifacial spasm for 2 years. Three-dimensional rotational angiography with selective arterial infusion of contrast medium(3DRA-IA)revealed that a distal part of the left AICA looping at the cisternal region was contacting the dome of the left VA aneurysm, although other imaging modalities did not show the exact course of the ipsilateral AICA. Constructive interference steady state magnetic resonance imaging revealed that both the left VA aneurysm and the left AICA had compressed the REZ of the left facial nerve. She underwent aneurysm clipping and decompression of the REZ by transposition of both the clipped aneurysm and the AICA using TachoSil^®. Her hemifacial spasm disappeared immediately after surgery without complication. Some fine arteries might compress the REZ in patients with hemifacial spasm associated with VA aneurysms. 3DRA-IA was more effective for accurate evaluation than other imaging modalities. Transposition of vascular structures using TachoSil^® is safe and effective for microvascular decompression surgery in such complicated cases.

A Case of Meningioma Originating from the Oculomotor Nerve

BACKGROUND

Schwannoma originating from the oculomotor nerve has been reported. However, meningioma originating from this nerve was unknown.

CASE DESCRIPTION

A 22-year-old woman presented with a unique case of meningioma originating from the oculomotor nerve manifesting as periorbital pain and diplopia beginning 4 months previously. Oculomotor nerve schwannoma was suggested by several pretreatment examinations. Tumor resection was considered risky for preservation of the oculomotor nerve function; therefore, gamma knife surgery (GKS) was performed. Six months later, she suffered right complete ptosis and worsened blurry vision. Corticosteroid was administered, but her symptoms did not improve. Magnetic resonance imaging showed the tumor lesion had grown larger. We decided to resect the tumor lesion because of her uncontrolled periorbital pain. The tumor had occupied the oculomotor cistern and was gross totally removed. Histologic diagnosis was surprisingly transitional meningioma. The tumor lesion occupied the oculomotor cistern and was refractory to GKS, with a progressive clinical course, which is more suggestive of meningioma than schwannoma, although extremely rare. Her periorbital pain and blurry vision gradually regressed, whereas complete oculomotor nerve palsy persisted.

CONCLUSIONS

In such a case, tumor resection after GKS should be considered.

[A Case Report of Brain Metastasis from Anal Canal Carcinoma]

A 55-year-old female with adenocarcinoma of anal canal(stage IV with lung, bone, and lymph node metastasis)underwent total pelvic exenteration surgery and chemotherapy. Chemotherapy was continued after the surgery. One month later, she presented to the emergency room with gait disorder and cognitive dysfunction. CT and MRI demonstrated metastatic brain tumor in the right cerebellar hemisphere. Craniotomy and CyberKnife surgery were performed. Histological examination revealed adenocarcinoma with atypical cells forming a papillary arrangement. She died 35 weeks after the surgery. Brain metastasis from anal carcinoma is very rare, but recent advances in chemotherapy are achieving favorable results of long-term survival, and this is likely to increase in the future. Early detection, early treatment, and combined therapy may improve the long-term outcome for patients.

[A Case of Bilateral Trigeminal Neuralgia and the Possible Onset Mechanisms Based on the Operative Findings]

Several cases of bilateral trigeminal neuralgia(TN)have been reported;however, the possible onset mechanism has rarely been discussed. We encountered a case of bilateral TN occurring in two stages. A 64-year-old woman presented with left TN. Magnetic resonance imaging showed the transverse pontine vein adhering to the left trigeminal root and superior cerebellar artery adhering to the right trigeminal root;however, no symptoms were noted. Immediately after microvascular decompression(MVD)on the left side, TN disappeared completely. However, 2 years postoperatively, the patient presented with right TN. The second MVD surgery revealed that the right cerebellar surface severely adhered to the dura mater, particularly under the surface of the tentorium. The arachnoid membrane at the cerebellopontine angle was slightly adhered. The patient was completely free from pain after the second MVD. The intraoperative findings suggested that the brain stem may have shifted and the cerebellopontine cistern may have narrowed because of cerebellar adhesion to the surrounding structures and arachnoid adhesion. We speculate that such structural changes in the posterior fossa after the first operation may have caused the asymptomatic vascular adhesion to change into the symptomatic offending adhesion over time.

[A Case of Primary Intracranial Malignant Melanoma Mimicking a Traumatic Brain Contusion]

Primary intracranial malignant melanoma(PIMM)is a rare neoplasm of the central nervous system, accounting for 1% of cases of malignant melanomas and 0.1% of cases of brain tumors. Here, we report a case of PIMM that was initially considered to be a traumatic brain contusion. A 44-year-old man was transferred to a local hospital because of general tonic convulsion after falling while riding a bike. CT showed an irregular high-density area in the left temporal pole, which was diagnosed as a traumatic contusion. MRI performed 3 months after the initial episode revealed an enlarged temporal lesion with surrounding edema, suggestive of a neoplasm. The MRI showed the lesion as mixed signal intensity, suggesting both solid and cystic components. Subtotal resection was performed, except for the tumor adhering to the peripheral middle cerebral arteries(MCAs). The definitive diagnosis was made based on pathological findings and no evidence of extracranial lesions. Gamma knife surgery was performed for the remnant tumor adjacent to MCAs. The radiologically positive tumor chronologically regressed, and the patient remained progression-free for 18 months. Radiological findings of PIMM vary but typically include high density on CT and hyperintensity on T1-weighted MRI. Close observation enabled early diagnosis based on the suspicion of a neoplasm according to atypical radiological findings. PIMM has a poor prognosis with an overall survival of 12.0 months without confirmative treatment. Gamma knife surgery might achieve suppression of this highly progressive tumor.

[Three Surgical Cases of Brain Metastasis from Renal Cell Carcinoma Occurring more than 10 years after Nephrectomy:Case Reports and Literature Review]

Renal cell carcinoma(RCC)can metastasize to the brain within several years;however, 20 cases of brain metastases have been reported after>10 years of the initial nephrectomy. Here, we report three cases of brain metastasis that occurred>10 years after nephrectomy for RCC. In general, RCC is radio-resistant, but stereotactic radiosurgery has been reported to be effective in some cases. To improve the functional and survival prognoses, delayed brain metastases from RCC should be aggressively resected.

Multistaged, multidirectional strategy for safe removal of large meningiomas in the pineal region

OBJECTIVE Pineal region meningiomas are rare and tend to be discovered only after they grow. Several simultaneous multidirectional approaches performed as a single operation have been proposed, but the best strategy to remove these deeply situated large meningiomas involving the deep vital venous system remains to be established. The authors advocate a multistaged, multidirectional approach to safely remove these challenging tumors. METHODS Four consecutive cases of meningioma in the pineal region were treated between April 2013 and June 2016. The 3 large (> 40 mm diameter) tumors were removed via multistaged, multidirectional approaches (2 surgeries in 2 patients and 3 surgeries in 1 patient) with gravity retraction of the occipital or parietal lobe. The large occipital skin incision extending bilaterally was used for the next operation from the contralateral side. Combinations of the occipital transtentorial approach with or without the transfalcine approach, occipital bitranstentorial/falcine approach, combined supra-/infratentorial transsinus approach, and contralateral parietal interhemispheric transcallosal approach were used. RESULTS Transient visual field deficits occurred after 2 of the 8 operations, but all tumors were removed grossly or subtotally without permanent surgery-related morbidity. The galenic venous system and straight sinus remained intact in all patients. During the follow-up period (mean 29.5 months [range 13-52 months]), there were no recurrences after the final operation. CONCLUSIONS A multistaged, multidirectional strategy with an intentional large occipital scalp incision and gravity retraction of the occipital lobe is a good choice for the safe removal of large meningiomas in the pineal region.

Limited Indications for Clipping Surgery of Paraclinoid Aneurysm Based on Long-Term Visual Morbidity

OBJECTIVE

Clipping of paraclinoid aneurysm is still challenging because of poor visual morbidity. The extradural temporopolar approach was applied to clip paraclinoid aneurysms, with the expectation of reducing visual morbidity. Factors related to poor visual morbidity were evaluated, to assess the results for clipping of paraclinoid aneurysms.

METHODS

A series of 40 unruptured paraclinoid aneurysms in 38 patients were clipped via extradural temporopolar approach. Preoperative and postoperative states of visual cognitive function and radiological outcomes were investigated. Aneurysms were classified into dorsal type or non-dorsal type, and small (<9 mm) or not-small (≥9 mm), respectively, to identify factors correlated with visual morbidity.

RESULTS

Complete clipping rate was 90.0% without any recurrence (mean: 5.2 years). Visual morbidity was unexpectedly high at 28.9%, including 2.7% of blindness immediately after the operation, and 23.7% and 2.7% at the final examination (mean: 3.6 years). Multivariate analysis showed aneurysm size was significantly correlated with worse visual outcome. Visual morbidity was 13.3% and 11.1% for dorsal and the non-dorsal small aneurysms, respectively, and all these cases showed visual field defect limited to the nasal quadrant without decreased visual acuity. In contrast, the non-dorsal not-small aneurysms showed significantly worse visual morbidity (60%) with decreased visual acuity.

CONCLUSIONS

Clipping via extradural temporopolar approach can achieve durable treatment for small unruptured paraclinoid aneurysms with acceptable visual morbidity. Visual morbidity of the not-small non-dorsal type, however, was poor. The indications for clipping of paraclinoid aneurysm should be limited to small aneurysms, especially the dorsal type in young patients.

Mixed pial and dural arteriovenous fistula after craniotomy: case report and literature review

Dural arteriovenous fistula (AVF) is known to occur after craniotomy, but mixed pial and dural AVF after craniotomy has not been reported. A 45-year-old man who had undergone surgical clipping of an unruptured aneurysm 2 years previously presented with small subcortical hemorrhage from mixed pial and dural AVF. Surgical disconnection could not be cured completely due to the granulomatous tissue around the aneurysm, and the presence of an undetected shunt. Postoperative digital subtraction angiography showed a new pial AVF supplied by the middle cerebral artery pial branches. Many branches were associated with the remnant aneurysm and pial AVF, so we did not try to embolize the fistula. Gamma knife surgery was performed as adjuvant radiotherapy, which achieved angiographically complete occlusion of the shunt points. Multimodal approaches including surgery, endovascular intervention, and radiotherapy are needed for radiological and clinical cure of mixed pial and dural AVF. Long-term follow up is essential.

Potential Risks and Limited Indications of the Supraorbital Keyhole Approach for Clipping Internal Carotid Artery Aneurysms

Background

Internal carotid artery (ICA) aneurysm may be a good target for supraorbital keyhole clipping. We discuss the surgical indications and risks of keyhole clipping for ICA aneurysms based on long-term clinical and radiologic results.

Methods

This was a retrospective analysis of 51 patients (aged 35–75 years, mean 62 years) with ICA aneurysms (mean 5.8 ± 1.8 mm) who underwent clipping via the supraorbital keyhole approach between 2005 and 2017. Neurologic and cognitive functions were examined by several methods, including the modified Rankin Scale and Mini-Mental Status Examination. The state of clipping was assessed 1 year and then every few years after the operation.

Results

Complete clipping was confirmed in 45 patients (88.2%), dog-ear remnants behind the clip persisted in 4 patients, and wrapping was performed in 2 patients. Mean duration of postoperative hospitalization was 3.4 ± 6.9 days. The mean clinical follow-up period was 6.6 ± 3.2 years. The overall mortality was 0, and overall morbidity (modified Rankin Scale score ≥2 or Mini-Mental Status Examination <24) was 3.9%. Completely clipped aneurysms did not show any recurrence during the mean follow-up period of 6.3 ± 3.1 years, but the 2 (3.9%) aneurysms with neck remnants showed regrowth.

Conclusions

The risk of neck remnant behind the clip blade is a drawback of supraorbital keyhole clipping. The surgical indication requires preoperative simulation and careful checking of the clip blade state is essential.

Keyhole strategy aiming at minimizing hospital stay for surgical clipping of unruptured middle cerebral artery aneurysms

OBJECTIVE

Aneurysms of the middle cerebral artery (MCA) are still most often treated by clipping through standard craniotomy, but a longer hospital stay is one of the main drawbacks of this treatment. The authors developed a pterional keyhole clipping strategy for unruptured MCA aneurysms with the intention of minimizing hospital stay. In this paper, they report on their experience with this approach and analyze the long-term neurological and radiological outcomes.

METHODS

A total of 160 relatively small unruptured MCA aneurysms (mean 6.4 mm) were clipped through the pterional keyhole approach (19–30 mm, mean 24.6 mm) in 149 patients (aged 34–79 years, mean 62 years). Neurological and cognitive function were examined by several scales, including the modified Rankin Scale (mRS) and Mini–Mental State Examination (MMSE). Patients’ level of depression was assessed using the Beck Depression Inventory and Hamilton Depression Scale. The state of clipping was assessed at 1 year and then every few years after the operation.

RESULTS

The mean duration of postoperative hospitalization was 2.3 ± 3.4 days; in 31.3% of the cases, the patients were discharged on the day after the operation (overnight hospital stay) and in 93.2% within 3 days. Of the patients younger than 60 years, 40.4% required only an overnight stay. Complete aneurysm neck clipping was confirmed in 157 cases (98.1%). None of the completely clipped aneurysms showed any recurrence during the mean follow-up period of 5.0 years. The mean length of clinical follow-up was 5.4 years. After 2 (1.3%) of the surgical procedures, the patients showed persistent neurological deficits, defined as mRS score 1, but the overall operative morbidity based on the International Study of Unruptured Intracranial Aneurysms (ISUIA) definition (mRS score ≥ 2 or MMSE score < 24) was 0% at the last examination. Depression scores were significantly improved after surgery, and in 85.6% of the cases the patients were satisfied with their cosmetic results.

CONCLUSIONS

Pterional keyhole clipping is less invasive than clipping via standard craniotomy, minimizes hospital stay, and achieves durable treatment for relatively small unruptured MCA aneurysms.

Spontaneous Regression of Germinomas After Salvage Surgery and Possible Mechanism of Induced Apoptosis

BACKGROUND

A few cases of spontaneous regression of germ cell tumors have been reported. Possible mechanisms include steroid medication, surgical intervention, diagnostic radiation exposure, and immune response. None of these hypotheses has been supported by sufficient data.

CASE DESCRIPTION

Two cases of germinoma demonstrated spontaneous regression before antitumor therapy. In the first case, a 19-year-old man presented with acute hydrocephalus due to a pineal mass and underwent emergent endoscopic third ventriculostomy. The pineal tumor started to regress on the 4th postoperative day after endoscopic third ventriculostomy. In the second case, a 22-year-old man presented with acute hydrocephalus and panhypopituitarism due to a suprasellar mass and underwent emergent external ventricular drainage, biopsy, and septostomy on the day of admission. Apparent regression of the tumor was discovered on the 5th day after initial surgery. Pathologic diagnosis was pure germinoma in both cases. Remarkable accumulations of CD4-positive lymphocytes and some apoptotic cells positive for terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling staining were detected in both cases. Diagnostic radiation exposure is the only common condition in all reported cases.

CONCLUSIONS

This unusual phenomenon of spontaneous regression of germinoma may be caused by a combination of pathognomonic characteristics of anatomic location with paraventricular development and stress induction as a trigger, such as salvage surgery or diagnostic radiation, including at extremely low dosage.

Surgical Strategies for Ruptured Complex Aneurysms Using Skull Base Technique and Revascularization Surgeries

Object:

Surgical clipping of paraclinoid aneurysm, thrombosed large aneurysm, and/or vertebral-basilar dissecting aneurysms can be very difficult and has relatively high morbidity. We describe our experience using skull base and bypass technique and discuss the advantages and its pitfalls.

Patients and Methods:

We retrospectively reviewed medical charts of 22 consecutive patients with complex aneurysmal lesions underwent skull base and/or bypass techniques between March 2012 and April 2017.

Results:

There were 5 patients with paraclinoid or internal carotid artery (ICA) aneurysm underwent modified extradural temporopolar approach with mini-peeling of the dura propria with suction decompression, 3 patients with ICA aneurysm underwent intradural anterior clinoidectomy, 12 patients with vertebral dissecting aneurysm through transcondylar fossa approach (6 patients underwent occipital artery-posterior inferior cerebellar artery [OA-PICA] bypass), 1 patients with vertebral artery dissection underwent superficial temporal artery-superior cerebellar artery and OA-PICA bypass through posterior transpetrosal approach, 1 patient with arteriovenous fistula at the ventral side of the craniovertebral junction through extremely far lateral approach. Surgical outcome was good recovery in 10 patients, moderate disability in 4, severe disability in 4, vegetative state in 2, and dead is 2 patients. The favorable outcome was 63.6%, and poor outcome was 36.4%, which showed poor grade subarachnoid hemorrhagic patients. No patient suffered any complication related to re-rupture and/or incomplete clipping.

Conclusion:

Skull base technique, which can create a wide and shallow operative space, allowed us to improve surgical outcome and to reduce the risk of intraoperative neurovascular injury for surgical treatment of deeply located complex aneurysms.

[Treatment of Brain Metastases from Papillary Thyroid Carcinomas:Five Surgical Cases in Our Hospital and a Literature Review]

Papillary thyroid carcinoma is the most common thyroid malignancy and usually has an indolent clinical course with a good prognosis. Brain metastasis from thyroid cancer is very rare, occurring in only 0.8-1.3% of all papillary thyroid carcinomas; therefore, the prognosis and treatment of the metastatic tumor are unclear. We describe 5 cases of brain metastases from papillary thyroid carcinoma treated with surgery between 2013 and 2017. Intracranial tumor resection was performed and brain metastases were pathologically diagnosed as papillary thyroid carcinoma in 2 men and 3 women aged 62-72 years(mean 67 years). The surgical treatment for the thyroid cancer was total thyroidectomy in 3 patients, hemithyroidectomy in 1, and no treatment in 1. The duration from initial diagnosis to brain metastasis was 0-155 months(mean 73.2 months). Two patients also received radioiodine therapy. Three patients had multiple lesions and 2 had single lesions. Four patients also had other metastases. Neuroimaging demonstrated intratumoral hemorrhages in 2 patients. The other 2 patients had intratumoral hemorrhage during the course of the disease. All patients received radiation therapy after surgery for brain metastases. Two patients died, but the other 3 have survived to date. The other 2 patients who had intratumoral hemorrhage during the course of the disease received ¹³¹I radioiodine therapy. It was reported that ¹³¹I radioiodine therapy resulted in collapse of the fragile peritumoral vessels. It is safe to perform head magnetic resonance imaging(MRI)before radioiodine therapy for thyroid cancer. Papillary thyroid carcinomas carry a good prognosis but some brain metastases have a poor prognosis due to the presence of other metastases or the patient's poor general condition. Treatments for patients in good general condition are needed to improve the clinical course and prognosis.

[A Case of Retro-Odontoid Pseudotumor in a Very Elderly Individual]

Retro-odontoid pseudotumors are mainly caused by aging or rheumatoid arthritis. We treated a very elderly patient with retro-odontoid pseudotumor. A 92-year-old man was admitted with the chief complaints of difficulty walking and progressive numbness in the right upper and lower extremities. Neurological examination revealed muscle weakness and exaggerated tendon reflexes of the right upper and lower extremities, and disturbance in skilled motor activities of the fingers, bilaterally. He had no bladder or rectal disturbances. The Japanese Orthopaedic Association(JOA)score for cervical myelopathy was 10/17. Rheumatoid arthritis was interpreted as negative. Radiography of the neck showed no atlanto-axial instability. Cervical magnetic resonance(MR)imaging revealed a mass located posterior to the C2 odontoid process, severely compressing the cervical cord. The patient underwent a C1 laminectomy and C2 half laminectomy without fixation to achieve cord decompression. Postoperatively, muscle weakness in the right upper and lower extremities was remarkably improved, and gait disturbance was also improved. However, skilled motor activities of the fingers on the right hand during tasks such as writing letters, holding a cup, and using chopsticks, were not improved. JOA score was improved to 14/17. Postoperative radiography revealed no atlanto-axial instability and MR imaging revealed adequate decompression of the spinal canal. Laminectomy without fixation is recommended as an effective and less invasive treatment for retro-odontoid pseudotumor, especially in very elderly patients without atlanto-axial instability.

Head-up display may facilitate safe keyhole surgery for cerebral aneurysm clipping

OBJECTIVE

The head-up display (HUD) is a modern technology that projects images or numeric information directly into the observer’s sight line. Surgeons will no longer need to look away from the surgical view using the HUD system to confirm the preoperative or navigation image. The present study investigated the usefulness of the HUD system for performing cerebral aneurysm clipping surgeries.

METHODS

Thirty-five patients underwent clipping surgery, including 20 keyhole surgeries for unruptured cerebral aneurysm, using the HUD system. Image information of structures such as the skull, cerebral vasculature, and aneurysm was integrated by the navigation software and linked with the positional coordinates of the microscope field of view. “Image injection” allowed visualization of the main structures that were concurrently tracked by the navigation image, and “closed shutter” switched the microscope field of view and the pointer image of the 3D brain image.

RESULTS

The HUD system was effective for estimating the location and 3D anatomy of the aneurysm before craniotomy or dural opening in most patients. Scheduled keyhole minicraniotomy and opening of the sylvian fissure or partial rectal gyrus resection were performed on the optimized location with a minimum size in 20 patients.

CONCLUSIONS

The HUD images superimposed on the microscope field of view were remarkably useful for less invasive and more safe aneurysm clipping and, in particular, keyhole clipping.

Less Invasive Modified Extradural Temporopolar Approach for Paraclinoid Lesions: Operative Technique and Surgical Results in 80 Consecutive Patients

Background  Extradural temporopolar approach for paraclinoid lesions can provide extensive and early exposure of the anterior clinoid process, and complete mobilization and decompression of the optic nerve and internal carotid artery, which can prevent intraoperative neurovascular injury. The present study investigated the usefulness of our less invasive modified technique and discussed its operative nuances. Methods  We retrospectively reviewed medical charts of 80 consecutive patients with neoplastic (21 patients) and vascular lesions (59 patients) who underwent the modified extradural temporopolar approach between September 2009 and March 2014. Results  Preoperative visual acuity worsened in 4 patients (5.0%) and worsening of visual field function occurred in 10 patients (12.5%). Postoperative outcome was good recovery in 71 patients, moderate disability in 6, severe disability in 2, and death in 1 (due to reruptured aneurysm). No operation-related mortality occurred in the series. Conclusion  Less invasive modified extradural temporopolar approach is safe and can be recommended for the surgical treatment of deeply located aneurysms and skull base tumors to reduce the risk of intraoperative optic neurovascular injury.

Involvement of Intracellular Cholesterol in Temozolomide-Induced Glioblastoma Cell Death

Glioblastoma (GBM) still carries a poor prognosis due to the refractoriness against antitumor drugs. Temozolomide (TMZ), one of the few standard therapy drugs against GBM worldwide, has only limited effect due to acquired TMZ resistance of GBM. Therefore, development of novel therapeutic methods to overcome the TMZ resistance of GBM is urgent. The brain is the most cholesterol-rich organ in the human body, so modulation of cholesterol in tumor cells originating from the brain including GBM may be a tumor-specific therapeutic strategy including enhancement of TMZ effects. The unique lipid metabolism of glioma has recently been reported, but the involvement of intracellular cholesterol in TMZ therapy is yet to be fully elucidated. This review summarizes the effect of modulation of intracellular cholesterol level on cancer therapy including GBM treatment and the implications for TMZ therapy. Our recent findings about the involvement of intracellular cholesterol in TMZ-induced GBM cell death are described.

“Birdlime” technique using TachoSil tissue sealing sheet soaked with fibrin glue for sutureless vessel transposition in microvascular decompression: operative technique and nuances

OBJECTIVE

Microvascular decompression (MVD) is effective for the treatment of trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia. The transposition technique is the standard procedure to avoid adhesions and granuloma around the decompression site but is more complex and difficult to perform than the interposition technique. The authors describe a simple and safe MVD transposition procedure they call the “birdlime” technique, which uses a tissue glue–coated collagen sponge soaked with fibrin glue, and the results of this technique.

METHODS

The authors retrospectively reviewed the medical charts and radiographic findings of 27 consecutive patients with TN (8 patients) and HFS (19 patients) who, between January 2012 and December 2015, had undergone an MVD transposition procedure utilizing a tissue glue–coated collagen sponge (TachoSil tissue sealing sheet) soaked with fibrin glue (Tisseel 2-component fibrin sealant, vapor heated). Offending arteries among the patients with TN were the superior cerebellar artery (SCA) in 5 patients, the SCA and anterior inferior cerebellar artery (AICA) in 2, and the AICA in 1. Those among the patients with HFS were the vertebral artery (VA) in 3 patients, the VA and AICA in 4, the VA and posterior inferior cerebellar artery (PICA) in 3, the PICA in 4, the AICA in 1, the AICA-PICA in 3, and the PICA and AICA in 1. Operations were performed according to the Jannetta procedure. The offending artery was transposed and fixed to the dura mater of the petrous bone using TachoSil pieces soaked with fibrin glue. Postoperative constructive interference in steady-state MRI was performed to evaluate the change in the position of the offending artery.

RESULTS

Transposition of the offending artery was easily and safely performed in all patients. All patients had total remission of symptoms directly after the procedure. No severe complications occurred. The postoperative course was uneventful. No recurrences, adhesions, or dysfunction of the cranial nerves was observed in any of the patients. Postoperative MRI showed that the offending vessels were displaced and fixed in the appropriate position.

CONCLUSIONS

The described transposition technique provides an easy and adjustable way to perform MVD safely and effectively. In addition, this transposition and fixation technique is simple and avoids the risk of needle injury close to the cranial nerves and vessels. This simple sutureless technique is recommended for MVD to reduce the risk of intraoperative neurovascular injury.

[Surgical Treatment for Traumatic Acute Subdural Hemorrhage in the Posterior Cranial Fossa:Three Cases Reports and Review of the Literature]

Acute subdural hemorrhage(ASDH)in the posterior cranial fossa is rare. Extremely unfavorable outcomes are reported among cases accompanied by supratentorial hematoma, brainstem contusion, or intracerebellar contusion. We report three cases surgically evacuated several times for traumatic ASDH in the posterior cranial fossa simultaneously accompanied by supratentorial hematomas. In our three presented cases, the mean age was 72.3 years, and all patients were male. The mechanisms of injury included traffic accidents in two cases and fall in one. The median Glasgow Coma Scale score on admission was 6. On admission, the patients had traumatic ASDH in the posterior cranial fossa accompanied by supratentorial hematoma, so they first underwent external decompression or ICP sensor insertion for the supratentorial lesions. However, after their first surgery, all patients developed upward herniation, and subsequently underwent suboccipital craniotomy and evacuation of hematomas. Glasgow Outcome Scales were death in one case, persistent vegetable state in one case, and severe disability in one case. The patients with ASDH in the posterior cranial fossa accompanied by supratentorial hematoma should immediately undergo suboccipital craniotomy and supratentorial decompression simultaneously when the hematomas compress the brainstem and upward herniation develops.

Long-Term Neurological and Radiological Results of Consecutive 63 Unruptured Anterior Communicating Artery Aneurysms Clipped via Lateral Supraorbital Keyhole Minicraniotomy

BACKGROUND

Treatments for unruptured anterior communicating artery (AcomA) aneurysm have relatively high morbidity.

OBJECTIVE

To assess the lateral supraorbital keyhole approach for safe and complete clipping of unruptured AcomA aneurysm and evaluate the long-term clinical and radiological outcomes, including cognitive and depressive status.

METHODS

A total of 63 patients (aged 41-79 yr, mean 64 yr) with relatively small AcomA aneurysms clipped via the lateral supraorbital approach were retrospectively analyzed among the 105 AcomA aneurysms treated by clipping from 2005 to 2014. Neurological and cognitive functions were examined by several scales, including the modified Rankin Scale (mRS) and Mini-Mental Status Examination. The depressive state was assessed using the Beck Depression Inventory and Hamilton Depression Scale. The state of clipping was assessed 1 yr and then every few years after the operation by 3-dimensional computed tomography angiography.

RESULTS

Complete neck clipping was confirmed in 62 aneurysms (98.4%). Perioperative complications occurred in 5 patients (5/63; mild frontalis muscle weakness in 3, anosmia in 1, and meningitis in 1). The mean clinical follow-up period was 5.2 ± 2.1 yr. No patient showed an mRS score more than 2 and all were completely independent in daily life. The depression scores were significantly improved after surgery. The overall mortality was 0% and overall morbidity (mRS score &gt; 2 or Mini-Mental Status Examination score &lt; 24) was 1.6%. All completely clipped aneurysms did not show any recurrence during the mean follow-up period of 4.9 ± 2.1 yr.

CONCLUSION

Lateral supraorbital keyhole approach to clip relatively small unruptured AcomA aneurysm promises less invasive and durable treatment.

Validation of effectiveness of keyhole clipping in nonfrail elderly patients with unruptured intracranial aneurysms

OBJECTIVE

Advanced age is known to be associated with a poor prognosis after surgical clipping of unruptured intracranial aneurysms (UIAs). Keyhole clipping techniques have been introduced for less invasive treatment of UIAs. In this study, the authors compared the complications and clinical and radiological outcomes after keyhole clipping between nonfrail elderly patients (≥ 70 years) and nonelderly patients.

METHODS

Keyhole clipping (either supraorbital or pterional) was performed to treat 260 cases of relatively small (≤ 10 mm) anterior circulation UIAs. There were 62 cases in the nonfrail elderly group (mean age 72.9 ± 2.6 years [± SD]) and 198 cases in the nonelderly group (mean age 59.5 ± 7.6 years). The authors evaluated mortality and morbidity (modified Rankin Scale score > 2 or Mini–Mental State Examination [MMSE] score < 24) at 3 months and 1 year after the operation, the general cognitive function by MMSE at 3 months and 1 year, anxiety and depression by the Beck Depression Inventory (BDI) and Hamilton Rating Scale for Depression (HAM-D) at 3 months, and radiological abnormalities and recurrence at 1 year.

RESULTS

Basic characteristics including comorbidities, frailty, and BDI and HAM-D scores were not significantly different between the 2 groups, whereas the MMSE score was slightly but significantly lower in the elderly group. Aneurysm location, largest diameter, type of keyhole surgery, neck clipping rate, and hospitalization period were not significantly different between the 2 groups. The incidence of chronic subdural hematoma was not significantly higher in the elderly group than in the nonelderly group (8.1% vs 4.5%, p = 0.332); rates of other complications including stroke and epilepsy were not significantly different. Lacunar infarction occurred in 3.2% of the elderly group and 3.0% of the nonelderly group. No patient in the elderly group required re-treatment or demonstrated recurrence of clipped aneurysms. The MMSE score at 3 months significantly improved in the nonelderly group but did not change in the elderly group. The BDI and HAM-D scores at 3 months were significantly improved in both groups. No patient died in either group. The morbidity at 3 months and 1 year in the elderly group (1.6% and 4.8%, respectively) was not significantly different from that in the nonelderly group (2.0% and 1.5%, respectively).

CONCLUSIONS

Keyhole clipping for nonfrail elderly patients with relatively small anterior circulation UIAs did not significantly increase the complication, mortality, or morbidity rate; hospitalization period; or aneurysm recurrence compared with nonelderly patients, and it was associated with improvement in anxiety and depression. Keyhole clipping to treat UIAs in the nonfrail elderly is an effective and long-lasting treatment.

Intracellular cholesterol level regulates sensitivity of glioblastoma cells against temozolomide-induced cell death by modulation of caspase-8 activation via death receptor 5-accumulation and activation in the plasma membrane lipid raft

Development of resistance against temozolomide (TMZ) in glioblastoma (GBM) after continuous treatment with TMZ is one of the critical problems in clinical GBM therapy. Intracellular cholesterol regulates cancer cell biology, but whether intracellular cholesterol is involved in TMZ resistance of GBM cells remains unclear. The involvement of intracellular cholesterol in acquired resistance against TMZ in GBM cells was investigated. Intracellular cholesterol levels were measured in human U251 MG cells with acquired TMZ resistance (U251-R cells) and TMZ-sensitive control U251 MG cells (U251-Con cells), and found that the intracellular cholesterol level was significantly lower in U251-R cells than in U251-Con cells. In addition, treatment by intracellular cholesterol remover, methyl-beta cyclodextrin (MβCD), or intracellular cholesterol inducer, soluble cholesterol (Chol), regulated TMZ-induced U251-Con cell death in line with changes in intracellular cholesterol level. Involvement of death receptor 5 (DR5), a death receptor localized in the plasma membrane, was evaluated. TMZ without or with MβCD and/or Chol caused accumulation of DR5 into the plasma membrane lipid raft and formed a complex with caspase-8, an extrinsic caspase cascade inducer, reflected in the induction of cell death. In addition, treatment with caspase-8 inhibitor or knockdown of DR5 dramatically suppressed U251-Con cell death induced by combination treatment with TMZ, MβCD, and Chol. Combined treatment of Chol with TMZ reversed the TMZ resistance of U251-R cells and another GBM cell model with acquired TMZ resistance, whereas clinical antihypercholesterolemia agents at physiological concentrations suppressed TMZ-induced cell death of U251-Con cells. These findings suggest that intracellular cholesterol level affects TMZ treatment of GBM mediated via a DR5-caspase-8 mechanism.

[Surgical Treatment of a Giant Olfactory Groove Schwannoma:A Case Report]

Schwannomas originating from the olfactory nerve are extremely rare because the olfactory nerve does not normally contain Schwann cells. We describe a case of a giant schwannoma of the olfactory groove. A 73-year-old woman presented with anosmia persisting for 10 months. Head computed tomography(CT)for head trauma at another hospital demonstrated a tumor lesion located in the left frontal lobe and paranasal sinus. She had never suffered epilepsy, and past medical history and family history identified no indicators. Neurological examination revealed anosmia and dementia. Head CT demonstrated a tumor lesion with bone erosion, causing a defect of about 5cm in the frontal base. Head magnetic resonance(MR)imaging with contrast medium indicated a lesion that was 6cm in diameter, with heterogeneous enhancement and severe perifocal edema in the left frontal base, extending into the paranasal cavity. The tumor was resected through a left extradural subfrontal approach with bicoronal frontal craniotomy. The endoscopic approach was also performed simultaneously to remove the tumor in the paranasal sinus. The cystic tumor was soft and easy to bleed. Intraoperatively the right olfactory nerve was confirmed, but the left olfactory nerve could not be identified because of replacement by the tumor, suggesting that the tumor had originated from the left olfactory nerve. The defect of the dura was repaired with femoral fascia, the pedunculated periosteal flap was laid over the frontal base, and the bone defect was repaired with the inner plate of the frontal calvaria. Postoperative head MR imaging with contrast medium revealed no residual lesion. The patient was discharged 25 days after surgery, without new neurological deficits. Histological examination identified mixed Antoni type A and Antoni type B schwannoma on hematoxylin and eosin staining and S-100 protein on immunostaining.

Flexible Ultrathin Endoscope Integrated with Irrigation Suction Apparatus for Assisting Microneurosurgery

BACKGROUND

Endoscopy can observe the anatomical components in a deeply located and/or hidden area during neurosurgical procedures under the operating microscope. We have newly developed a flexible ultrathin endoscope integrated with irrigation suction apparatus (FUEISA) to visualize deeply located and/or hidden areas for assisting microneurosurgery.

OBJECTIVE

The present study investigated the usefulness of the FUEISA system for direct clipping surgery of cerebral aneurysms.

METHODS

Twenty-one patients underwent microneurosurgery assisted with the FUEISA system for direct clipping of cerebral aneurysms. The flexible ultrathin endoscope (outer diameter 0.75mm) consists of an image guide (6000 dpi) and a light guide, integrated with the irrigation suction apparatus. This endoscopic system was inserted before and after clipping to observe the anatomical conditions surrounding the lesions.

RESULTS

In all cases, handling and operation of the FUEISA was technically successful during the surgical procedure. The ultrathin endoscope was adequately integrated with the irrigation suction apparatus in all cases. General anatomy visualization including the lenticulostriate arteries, medial striate arteries, and/or internal carotid artery perforators was possible, and the correct clip positioning and vessel conditions were easily checked. The endoscope revealed that the clip had been positioned incorrectly in one case. No complications associated with the endoscopic system occurred.

CONCLUSIONS

The FUEISA system can be applied with safe manipulation, which was remarkably useful for confirmation of the presence of perforators and cranial nerves behind the lesions, particularly anatomical components located in deep and/or hidden areas during clipping of cerebral aneurysms.

Modified extradural temporopolar approach with mini-peeling of dura propria for paraclinoid and/or parasellar tumors: Operative technique and nuances

Background:

Modified extradural temporopolar approach (EDTPA) with mini-peeling of the dura propria can provide extensive exposure of the anterior clinoid process and early exposure, as well as complete mobilization and decompression of the optic nerve and internal carotid artery, which can prevent intraoperative neurovascular injury for paraclinoid and/or parasellar lesions. The present study investigated the usefulness of this modified technique and discusses the operative nuances.

Methods:

We retrospectively reviewed medical charts of 27 consecutive patients with neoplastic paraclinoid and/or parasellar lesions who underwent this modified approach between September 2009 and August 2016.

Results:

Preoperative visual acuity worsened in 2 patients (7.4%), and worsening of visual field function occurred in 2 patients (7.4%). Postoperative outcome was good recovery in 25 patients (92.6%) and moderate disability in 2 (7.4%). No operation-related mortality occurred in the series.

Conclusions:

The modified EDTPA is safe and recommended for surgical treatment of paraclinoid and/or parasellar tumors to reduce the risk of intraoperative optic neurovascular injury.

Horizontal distance of anterior communicating artery aneurysm neck from anterior clinoid process is critically important to predict postoperative complication in clipping via pterional approach

Background:

The difficulty of clipping aneurysm of the anterior communicating artery (AcomA) depends on the size, direction, positional relationship with the parent artery, and height from the anterior frontal base. Cases of clipping unruptured AcomA aneurysm through pterional approach were analyzed to investigate the importance of the horizontal distance from the base of the anterior clinoid process.

Methods:

Twenty-six consecutive unruptured AcomA aneurysms were treated by clipping through pterional approach in 10 males and 11 females aged 37–77 years (mean 61.8 years). Size and direction of the aneurysm, and vertical distance from the anterior frontal base and horizontal distance from the base of the anterior clinoid process were measured by preoperative three-dimensional computed tomography angiography (3D-CTA). Correlations with occurrence of clinical complications and computed tomography (CT) abnormalities after operation were investigated.

Results:

The aneurysms had a mean size of 4.7 mm (range 2.1–8.9 mm). Three patients suffered complications and all had anosmia. Three patients had CT abnormality and all were contusion. The mean horizontal distance from the base of the anterior clinoid process was −4.7 mm (range −12.3–3.5 mm). The patients were divided into the anterior and posterior groups with the boundary set at −5 mm. There were no significant complications between two groups (P = 0.26). There were statistically significant CT abnormalities in posterior group (P = 0.025).

Conclusion:

The horizontal distance from the base of the anterior clinoid process is important to predict CT abnormalities and complications in clipping of AcomA aneurysm through pterional approach.

Usefulness of dural surface tracing of the cortical vessels with indocyanine green videoangiography just prior to dural opening for various cerebrovascular diseases

Background:

Indocyanine green (ICG) videoangiography can be used to delineate the locations of the cortical vessels just prior to dural opening, allowing safe and optimal dural opening. The present clinical series demonstrates the adjunct use of ICG videoangiography to optimize dural opening for the treatment of various cerebrovascular diseases.

Methods:

A total of 45 patients underwent surgery for superficial temporal artery-middle cerebral artery bypass (40), arteriovenous malformation (2), and dural arteriovenous fistula (3) between January 2012 and December 2016. After the dura had been exposed, ICG (0.25 mg/kg) was administered intravenously from the peripheral vein as a bolus just prior to dural opening. The operating microscope equipped with a fluorescent filter was used to examine the illuminated field of interest, and real-time flow assessment of the underlying cortical vessels and/or dural sinus was performed. The target recipient arteries for anastomosis or vascular malformations were visualized through the dura and marked using a pyoktanin pen on the dura mater.

Results:

The optimal dural opening was performed for anastomosis, and safety was ensured by locating the vascular malformations through the dura mater in all cases. The cortical vessel injury was avoided in all cases. No complication was related to this procedure.

Conclusions:

Dural surface tracing of the cortical vessels with ICG videoangiography just prior to dural opening is a useful technique, which allows optimal and safe dural opening for treatment of various cerebrovascular diseases.

Modified extradural temporopolar approach with suction decompression for clipping of large paraclinoid aneurysm: Technical note

Background:

Surgical clipping of complicated large paraclinoid aneurysms are still challenging because strong adhesion of aneurysm itself may hinder the dissection of the perforators and the surrounding anatomical structures from the aneurysm dome.

Methods:

We describe 13 consecutive patients and the clipping of complicated, large-sized paraclinoid aneurysms using a modified extradural temporopolar approach combined with retrograde suction decompression and discuss its advantages and pitfalls.

Results:

Modified extradural temporopolar approach with suction decompression (SD) assistance was performed in all patients. There was no complication related to the surgical procedure. Postoperative outcome was good recovery in 7 patients, moderate disability in 4, and severe disability in 2 caused by severe subarachnoid hemorrhage. Favorable outcomes were achieved in 10 patients (84.6%).

Conclusion:

We recommend its less invasive, safe, and useful combined technique in the treatment of symptomatic paraclinoid aneurysms, which carry the risk of neurovascular injury caused by dissection from the aneurysm dome.

[A Case of Coexistent Glossopharyngeal Neuralgia and Hemifacial Spasm Successfully Treated with Transposition of the Vertebral Artery]

A case of coexistent glossopharyngeal neuralgia and hemifacial spasm was treated by transposition of the vertebral artery. A 60-year-old man was referred to our hospital due to pain in the left posterior part of the tongue that was difficult to control with oral medication at a local hospital. The diagnosis was left glossopharyngeal neuralgia based on the symptoms, imaging findings, and lidocaine test results. Moreover, the patient had left hemifacial spasm. Microvascular decompression was performed, which confirmed that the vertebral artery was compressing the lower cranial nerve and the posterior inferior cerebellar artery was compressing the root exit zone of the facial nerve. The vertebral artery and posterior inferior cerebellar artery were transposed using TachoSil^®. After the surgery, both glossopharyngeal neuralgia and hemifacial spasm disappeared, and the patient was discharged.

[A Case of Foramen Magnum Meningioma Manifesting as Hypoglossal Nerve Palsy]

We report a case of foramen magnum meningioma manifesting as hypoglossal nerve palsy. A 72-year-old woman presented with progressive hypoglossal nerve palsy and lingual atrophy on the left side. Gadolinium-enhanced T1-weighted magnetic resonance imaging revealed a heterogeneously enhanced mass lesion with dural tail sign partially extending into the hypoglossal canal. The transcondylar approach was performed to expose the hypoglossal canal and resect the tumor completely. Histological examination revealed a transitional meningioma. The postoperative course was uneventful. Hypoglossal nerve palsy improved gradually after the operation.

Effect of Fibrin Glue Injection Into the Cavernous Sinus for Hemostasis During Transcavernous Surgery on the Cerebral Venous Draining System

BACKGROUND: The extradural temporopolar transcavernous approach can be used to treat central skull base pathologies, but control of bleeding from the opened cavernous sinus is essential. Oxidized cellulose cotton packing and fibrin glue injection can be used, but the effect on the postoperative venous draining pattern remains unclear.

OBJECTIVE: To investigate changes in the venous drainage pattern immediately after transcavernous surgery with and without fibrin glue injection into the bleeding cavernous sinus.

METHODS: A total of 82 patients treated via the transcavernous approach were retrospectively divided into 2 groups based on the hemostasis methods. Both pre- and postoperative angiography and/or 3-dimensional computed tomography venography were available for 24 patients in the cotton packing group and 12 patients in the fibrin glue group.

RESULTS: Postoperative change in the venous draining pattern was observed in 5 of the 24 patients in the cotton packing group and in 3 of the 12 patients in the fibrin glue group. One of the 82 patients showed postoperative brain swelling due to obstruction of the sphenoparietal sinus. The volume of injected fibrin glue ranged from 0.5 to 2.5 mL (mean, 1.1 ± 0.5 mL), but none of the patients had brain swelling.

CONCLUSION: Direct fibrin glue injection into the opened cavernous sinus is relatively safe, but a change in the venous draining pattern occurs in 25% of patients. The study indicates the potential danger of the change in the venous draining pattern and recommends limiting the injection volume of fibrin glue in transcavernous surgery to avoid complications related to venous congestion.