Mitsutoshi Iwaasa

Impact of clipping versus coiling on postoperative hemodynamics and pulmonary edema after subarachnoid hemorrhage.

Volume management is critical for assessment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). This multicenter prospective cohort study compared the impact of surgical clipping versus endovascular coiling on postoperative hemodynamics and pulmonary edema in patients with SAH. Hemodynamic parameters were measured for 14 days using a transpulmonary thermodilution system. The study included 202 patients, including 160 who underwent clipping and 42 who underwent coiling. There were no differences in global ejection fraction (GEF), cardiac index, systemic vascular resistance index, or global end-diastolic volume index between the clipping and coiling groups in the early period. However, extravascular lung water index (EVLWI) and pulmonary vascular permeability index (PVPI) were significantly higher in the clipping group in the vasospasm period. Postoperative C-reactive protein (CRP) level was higher in the clipping group and was significantly correlated with postoperative brain natriuretic peptide level. Multivariate analysis found that PVPI and GEF were independently associated with high EVLWI in the early period, suggesting cardiogenic edema, and that CRP and PVPI, but not GEF, were independently associated with high EVLWI in the vasospasm period, suggesting noncardiogenic edema. In conclusion, clipping affects postoperative CRP level and may thereby increase noncardiogenic pulmonary edema in the vasospasm period. His trial is registered with University Hospital Medical Information Network UMIN000003794.

Revascularization for Acute Ischemic Stroke Is Safe for Rivaroxaban Users

BACKGROUND The safety of recombinant tissue plasminogen activator (rt-PA) and/or endovascular therapy for patients using the novel oral anticoagulant (NOAC) for atrial fibrillation remains unclear. METHODS We report a patient who was treated by both rt-PA and endovascular thrombectomy who suffered from acute ischemic stroke under treatment with NOAC. RESULTS An 83-year-old woman had a medical history with ischemic stroke due to paroxysmal atrial fibrillation and was then administered 10 mg of rivaroxaban daily. Although she took rivaroxaban in the morning, ischemic stroke recurred at midnight of that day. Soon after transferring to our hospital, we confirmed right middle cerebral artery (MCA) occlusion in the patient and then initiated treatment with intravenous rt-PA. Although no hemorrhagic complication occurred, recovery of her symptoms was not seen, and endovascular thrombectomy was performed. Although the inferior branch of the MCA was recanalized, an infarct was seen in her left frontal lobe. Hemorrhagic transformation was not observed during or after these combined treatments. CONCLUSIONS Thrombolysis and/or endovascular thrombectomy might be safe for patients treated with the new anticoagulant rivaroxaban.

Identification of venous sinus, tumor location, and pial supply during meningioma surgery by transdural indocyanine green videography

OBJECT Indocyanine green (ICG) videography is commonly used in the neurosurgical field for minimally invasive neurosurgery. The aim of this study was to evaluate a new intraoperative imaging modality by performing transdural ICG videography during surgery for meningiomas. METHODS Between March 2011 and April 2012, 10 patients with meningiomas received intravenous injection of 12.5 mg ICG just prior to dural opening. The cases comprised 8 convexity meningiomas and 2 foramen magnum meningiomas. Efficacy of the transdural ICG videography was assessed in terms of the tumor volume, the circulation time from the first appearance of the vessel to the appearance of the venous sinus, the tendency to bleed, and the discrimination of the venous sinus. RESULTS The mean tumor volume was 71.6 ± 87.9 ml (the mean is expressed ± SD throughout). The cortical arteries, veins, and the venous sinus were identified by the ICG videography transdurally. The projection of the meningiomas was identified by a shadow (which the authors call the eclipse sign). Total eclipse signs were obtained in 8 cases and partial eclipse signs were obtained in 2 cases; tumor volume in the latter was more than 200 ml. In 5 of 10 cases the adjacent venous sinuses were exposed and were successfully visualized by ICG videography in 5.92 ± 1.05 seconds from the first appearance of the vessel. In 5 of 10 cases the total and the partial eclipse signs were diminished in 3.46 ± 1.31 seconds. The diminishment of the total and the partial eclipse sign was earlier than the visualization of the venous sinus (p = 0.011, t-test), revealing bleeding from the tumor that was observed until coagulation of the feeding arteries from the intracranial arteries. CONCLUSIONS Prior to opening of the dura mater, transdural ICG videography was used successfully to visualize the dural attachment of meningiomas and the venous sinus, resulting in safe and appropriate dural opening. The diminishment of the total and partial eclipse signs may represent significant feeding from the intracranial arteries and a tendency to bleed during resection.

Hybrid Assistive Limb (HAL) Rehabilitation in Patients with Acute Hemorrhagic Stroke

The efficacy of hybrid assistive limb (HAL) rehabilitation in the acute phase of stroke remains unclear. The purpose of this study was to evaluate the outcomes of patients with acute intracranial hemorrhage (ICH) who were treated with or without HAL rehabilitation. Among 270 patients with acute ICH from 2009 to 2014, 91 patients with supratentorial ICH were included in this retrospective study. Of these, 14 patients (HAL group) received HAL rehabilitation at approximately 1 week after ICH occurrence, while the remaining 77 patients received usual rehabilitation without HAL (N-HAL group). We obtained various patient data from the hospitals where the patients were moved to for further rehabilitation. Statistical comparisons were performed for the characteristics of the ICH patients, and outcomes between the HAL and N-HAL groups. There were no differences in outcomes between the HAL and N-HAL groups. However, patients with right ICH in the HAL group exhibited a significant association with a functional independence measure (FIM) score of ≥ 110 compared with patients in the N-HAL group (HAL group: 81.8%, N-HAL group: 43.9%, P = 0.04). In patients with right ICH, HAL rehabilitation was associated with improved outcomes as evaluated by the FIM score. Thus, HAL rehabilitation may improve outcomes of acute ICH in appropriately selected patients.

1-Methyl-4-phenylpyridinium ion, a toxin that can cause parkinsonism, alters branched structures of DNA.

During replication, human mitochondrial DNA (mtDNA) takes on a triple‐stranded structure known as a D‐loop, which is implicated in replication and transcription. 1‐Methyl‐4‐phenylpyridinium ion (MPP+), a toxin inducing parkinsonism, inhibits mtDNA replication, possibly by resolving the D‐loops. For initiation of mtDNA replication, mitochondria are thought to have another triple‐stranded structure, an R‐loop. The R‐loop, which is resolved by a bacterial junction‐specific helicase, RecG, is also resolved by MPP+. Because mitochondrial D‐loops are likewise resolved by RecG, the D‐ and R‐loops may share a similar branched structure. MPP+ resolves cruciform DNA in supercoiled DNA. MPP+ converts a stacked conformation to an extended conformation in a synthetic Holliday junction. This conversion is reversed by 1 mm Mg2+, as is the resolution of the D‐loops or cruciform DNA. These observations suggest that the junction structure of mitochondrial D‐ and R‐loops is affected by MPP+.

Neurohypophyseal Granulomatous Germinoma Invading the Right Cavernous Sinus: Case Report and Review of the Literature

We encountered a rare case of neurohypophyseal germinoma with a prominent granulomatous reaction, which invaded the right cavernous sinus. The neuroimaging and histopathology features in this case were unique, distinguishing it from other types of suprasellar lesions. A 13-year-old boy presented with loss of appetite and polyuria; both symptoms were present for 1 year, and headache, general fatigue and blurred vision present for the prior 2 months. On admission, neurological examination indicated bitemporal hemianopsia and optic atrophy. Endocrinological exam showed panhypopituitarism. Tumor markers such as α-fetoprotein, human growth hormone, carcinoembryonic antigen, and placental alkaline phosphatase were negative. Brain CT revealed a suprasellar tumor with calcification. MR T1-weighted and T2-weighted images showed the tumor to be isointense to normal brain parenchyma and to be enhanced densely. The tumor also involved the right cavernous sinus, so that a biopsy was performed by the transsphenoidal approach. On pathologic examination of the specimen, typical large tumor cells with lymphocytic cell infiltration and prominent granulomatous reaction were observed. Neurohypophyseal granulomatous germinoma was diagnosed. Radiotherapy was performed with a total dose of 51 Gy and the tumor shrank remarkably. The patient returned to school under hormone replacement therapy.

Safety and feasibility of combined coiling and neuroendoscopy for better outcomes in the treatment of severe subarachnoid hemorrhage accompanied by massive intraventricular hemorrhage

Subarachnoid hemorrhage (SAH) with intraventricular hemorrhage (IVH) is associated with poor outcomes. The aim of this study was to evaluate the safety and feasibility of combined coiling and neuroendoscopy for treating severe SAH with massive IVH. Between April 2008 and June 2011, 49 patients with a severe SAH were treated at the Department of Neurosurgery, Fukuoka University, Japan; 10 of these patients had a massive IVH with a ruptured aneurysm. All 10 patients (three men and seven women; mean age, 63.1±8.5 years) were treated with coiling and neuroendoscopic removal of the IVH within 2 days of onset. Coiling was successfully performed at a mean volume embolization ratio of 21.8±5.5%. Neuroendoscopic removal of the IVH reduced the mean Graeb score from 10.5±2.0 to 4.8±2.5 (p=0.005). All external drains were removed on day 3. No rebleeding or acute hydrocephalus was noted. The Glasgow Outcome Scale scores at discharge indicated two patients with good recovery, three with moderate disability, four in a vegetative state, and one dead. A good modified Rankin Scale (mRS) score (0-2) at least 6 months later (mean follow-up period, 15.4±9.2 months) was observed for five patients (50%), and a poor mRS score (3-6) was observed for the remaining four patients. Neuroendoscopically removing the IVH from all of the ventricles between the lateral and the fourth ventricle and coiling the ruptured aneurysm is a safe, feasible approach for treating severe SAH with massive IVH.

Fusion Technique Using Three-Dimensional Digital Subtraction Angiography in the Evaluation of Complex Cerebral and Spinal Vascular Malformations

OBJECTIVE The authors introduce a new fusion technique using 2 three-dimensional digital subtraction angiography images acquired by a flat-panel detector angiographic system to understand the detailed angioarchitecture of complex cerebral and spinal vascular malformations. METHODS Eleven consecutive cases of arteriovenous fistula or arteriovenous malformation with lesions that involved 2 major vessels (i.e., internal carotid arteries, external carotid arteries, vertebral arteries, or spinal arteries) were included. Three-dimensional rotational angiography was performed in each affected vessel after conventional cerebral or spinal angiography. Subsequently, the 2 three-dimensional digital subtraction angiography images were fused. RESULTS The fused images provided the accurate three-dimensional angioarchitecture of complex vascular malformations clearly with high spatial resolution. In particular, the relationship between the nidus/fistulous point, the feeding arteries from each major vessel, and the draining veins could be easily delineated from different directions and multiple angles. Surgical or endovascular treatment was performed in all cases based on the information from these fused three-dimensional images. CONCLUSIONS A fusion technique using two three-dimensional digital subtraction angiography is beneficial for preoperative planning and successful treatment in cases of complex cerebral and spinal vascular malformations.

Unilateral Trans-cerebellomedullary Fissure Approach for Occipital Artery to Posterior Inferior Cerebellar Artery Bypass during Aneurysmal Surgery

Occipital artery (OA) to the posterior inferior cerebellar artery (PICA) bypass is indispensable for the management of complex aneurysms of the PICA that cannot be reconstructed with surgical clipping or coil embolization. Although OA-PICA bypass is a comparatively standard procedure, the bypass is difficult to perform in some cases because of the location and situation of the PICA. We describe the usefulness of the unilateral trans-cerebellomedullary fissure (CMF) approach for OA-PICA bypass. Thirty patients with aneurysms in the vertebral artery (VA) or PICA were treated using OA-PICA bypasses between 2010 and 2015. Among them, the unilateral trans-CMF approach was used for OA-PICA anastomosis in 13 patients. The surgical procedures performed on and the medical records of all the patients were retrospectively reviewed. The unilateral trans-CMF approach was performed for two reasons depending on the PICA location or situation: either because the caudal loop could not be used as a recipient artery because of arterial dissection (3 patients) or because the tonsillo-medullary segment that was located in the upper part of the CMF did not have a caudal loop that was large enough (10 patients). The trans-CMF approach provided a good operative field for the OA-PICA bypass and the anastomosis were successfully performed in all patients. When the recipient artery was located in the upper part of the CMF, the unilateral trans-cerebello-medullary fissure approach provided a sufficient operative field for OA-PICA anastomosis.

Endoscopic surgery via a combined frontal and suboccipital approach for cerebellar hemorrhage

Background: Spontaneous cerebellar hemorrhages (CHs), which frequently require surgical intervention, are life-threatening and can be complicated by intraventricular hemorrhages (IVHs) and obstructive hydrocephalus. Commonly, endoscopic surgery is performed to remove CHs via a suboccipital approach (SA) alone. At our institution, when patients exhibited supratentorial IVH-associated hydrocephalus, we used a combined frontal and suboccipital approach (CA) to evacuate both CHs and supratentorial IVHs. The present study retrospectively evaluated the effectiveness and safety of this CA, as no prior studies examining this approach currently exist. Methods: Twenty-six patients with spontaneous CH were surgically treated at our hospital from April 2009 to March 2016. Twenty-two patients who could independently perform activities of daily living before the onset underwent endoscopic surgery to evacuate the CHs; among these, 13 patients underwent the SA alone, while nine underwent the CA. We assessed and compared the patients’ baseline characteristics, surgical results, and prognosis at 1 month after the intervention between the SA and CA groups. Results: Patients who underwent the CA had significantly poorer consciousness before the surgery owing to IVH extension and obstructive hydrocephalus. However, the surgical results and prognosis at 1 month were not significantly different between the two approaches. The CH-associated IVHs were successfully removed with the CA and resulted in shorter external ventricular drainage (EVD) placement durations. Conclusion: Endoscopic surgery performed via the CA appeared to neutralize the deteriorating effects of CH-associated IVHs. Surgical strategies employing the CA may have the potential to improve the prognosis of patients with CH.