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Sphenopalatine ganglion stimulation for vasospasm after experimental subarachnoid hemorrhage

Laboratory investigation

Masataka Takahashi, Zhen-Du Zhang, and R. Loch Macdonald

Object

Sphenopalatine ganglion stimulation activates perivascular vasodilatory nerves in the ipsilateral anterior circle of Willis. This experiment tested whether stimulation of the ganglion could reverse vasospasm and improve cerebral perfusion after subarachnoid hemorrhage (SAH) in monkeys.

Methods

Thirteen cynomolgus monkeys underwent baseline angiography followed by creation of SAH by placement of autologous blood against the right intradural internal carotid artery, the middle cerebral artery (MCA), and the anterior cerebral artery. Seven days later, angiography was repeated, and the right sphenopalatine ganglion was exposed microsurgically. Angiography was repeated 15 minutes after exposure of the ganglion. The ganglion was stimulated electrically 3 times, and angiography was repeated during and 15 and 30 minutes after stimulation. Cerebral blood flow (CBF) was monitored using laser Doppler flowmetry, and intracranial pressure (ICP) was measured throughout. The protocol was repeated again. Evans blue was injected and the animals were killed. The brains were removed for analysis of water and Evans blue content and histology.

Results

Subarachnoid hemorrhage was associated with significant vasospasm of the ipsilateral major cerebral arteries (23% ± 10% to 39% ± 4%; p < 0.05, paired t-tests). Exposure of the ganglion and sham stimulation had no significant effects on arterial diameters, ICP, or CBF (4 monkeys, ANOVA and paired t-tests). Sphenopalatine ganglion stimulation dilated the ipsilateral extracranial and intracranial internal carotid artery, MCA, and anterior cerebral artery compared with the contralateral arteries (9 monkeys, 7% ± 9% to 15% ± 19%; p < 0.05, ANOVA). There was a significant increase in ipsilateral CBF. Stimulation had no effect on ICP or brain histology. Brain water content did not increase but Evans blue content was significantly elevated in the MCA territory of the stimulated hemisphere.

Conclusions

Sphenopalatine ganglion stimulation decreased vasospasm and increased CBF after SAH in monkeys. This was associated with opening of the blood-brain barrier.

Open access

Adult cerebellar glioblastoma categorized into a pediatric methylation class with a unique radiological and histological appearance: illustrative case

Takahiro Ono, Felix Hinz, Shogo Tanaka, Masataka Takahashi, Hiroshi Nanjo, Andreas von Deimling, and Hiroaki Shimizu

BACKGROUND

Recent studies report that cerebellar glioblastoma (GBM) is categorized into the RTK1 methylation class. GBM pediatric RTK (pedRTK) subtypes are distinct from those of adult GBM. We present a unique adult case of cerebellar GBM classified into the pedRTK subtype.

OBSERVATIONS

Magnetic resonance imaging revealed a homogeneous enhancing lesion in the right cerebellum in a 56-year-old woman presenting with ataxia and dizziness. Arterial spin labeling and angiographic findings and the intraoperative orange-colored tumor appearance were reminiscent of hemangioblastoma. She showed an atypical presentation in terms of high glucose metabolism. The histological diagnosis was high-grade glioma with differentiation similar to central nervous system neuroblastoma. The methylation class was GBM pedRTK1. Consistent with this classification, immunoexpression was positive for SOX10 and negative for ANKRD55. She underwent craniospinal radiotherapy (23.4 Gy) with a boost to the tumor bed (total 55.8 Gy). Twelve courses of temozolomide therapy were administered. There was no recurrence 18 months after surgery.

LESSONS

Radiological and intraoperative findings, such as hemangioblastoma and high glucose metabolism, were notable characteristics in the present case. Both glial and neuronal differentiation and SOX10 immunoexpression were presenting pathological features. Similar cerebellar GBMs might form a previously unestablished subtype. Establishing effective molecular diagnoses is important.

Open access

Detailed molecular and pathological analyses of primary intracranial embryonal rhabdomyosarcoma with a BRAF mutation: illustrative case

Masamichi Abe, Takahiro Ono, Felix Hinz, Masataka Takahashi, Yuko Hiroshima, Koya Kodama, Michihiro Yano, Hiroshi Nanjo, Tsutomu Takahashi, Andreas von Deimling, and Hiroaki Shimizu

BACKGROUND

The etiological significance of the RAS and PI3K pathways has been reported in systemic embryonal rhabdomyosarcoma (ERMS) but not in primary intracranial ERMS (PIERMS). Herein, the authors present a unique case of PIERMS with a BRAF mutation.

OBSERVATIONS

A 12-year-old girl with progressive headache and nausea was diagnosed with a tumor in the right parietal lobe. Semi-emergency surgery revealed an intra-axial lesion that was histopathologically identical to an ERMS. Next-generation sequencing indicated a BRAF mutation as a pathogenic variation, but the RAS and PI3K pathways showed no alteration. Although there is no established reference class for PIERMS, the DNA methylation prediction was closest to that of ERMS, indicating the possibility of PIERMS. The final diagnosis was PIERMS. The patient underwent local radiotherapy (50.4 Gy) and multiagent chemotherapy, with no recurrence for 12 months after surgery.

LESSONS

This may be the first case demonstrating the molecular features of PIERMS, especially the intra-axial type. The results showed a mutation in BRAF but not in the RAS and PI3K pathways, which is different from the existing ERMS features. This molecular difference may cause differences in DNA methylation profiles. Accumulation of the molecular features of PIERMS is necessary before any conclusions can be drawn.

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Direct repair of a blisterlike aneurysm on the internal carotid artery with vascular closure staple clips

Technical note

Toshiharu Yanagisawa, Kazuo Mizoi, Taku Sugawara, Akira Suzuki, Tohru Ohta, Naoki Higashiyama, Masataka Takahashi, Toshio Sasajima, and Hiroyuki Kinouchi

✓ Vascular closure staple clips made of titanium were originally developed for microvascular anastomosis. Clinical applications for these clips include arteriotomy closure for carotid endarterectomy, extracranial—intracranial bypass, and dural closure. This is the first report in which vascular closure staple clips have been used successfully for direct repair of a tear on the internal carotid artery (ICA). This report involves a 65-year-old man who presented with sudden onset of headache. Admission computerized tomography scans demonstrated a diffuse and thick subarachnoid hemorrhage in the basal cisterns. Cerebral angiograms demonstrated a broad-based, small bulge on the superomedial wall of the left ICA. Intraoperatively, an extremely thin-walled aneurysm was seen on the segment of the ICA at the C-2 vertebral level. The aneurysm ruptured abruptly, although no surgical manipulation was being performed on the aneurysm itself. After temporary clips were applied on the vessel, a large tear of the ICA was repaired with vascular closure staple clips. Reconstruction with the vascular closure staple clips required only a short period of temporary occlusion of the ICA. Postoperative angiograms revealed reduction of the aneurysm bulge and good patency of the ICA. The postoperative course was uneventful, and the patient has been free of symptoms. The vascular closure staple clipping procedure is useful for urgent repair of an aneurysm tear. This method is a new treatment option for these fragile aneurysms in cases in which other options, such as encircling clips or bypass procedures, may have drawbacks or be impossible.

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Alteration in voltage-dependent calcium channels in dog basilar artery after subarachnoid hemorrhage

Laboratory investigation

Elena Nikitina, Ayako Kawashima, Masataka Takahashi, Zhen-Du Zhang, Xueyuan Shang, Jinglu Ai, and R. Loch Macdonald

Object

The L-type Ca++ channel antagonists like nimodipine have limited efficacy against vasospasm after subarachnoid hemorrhage (SAH). The authors tested the hypothesis that this is because SAH alters these channels, rendering them less responsible for contraction.

Methods

Basilar artery smooth muscle cells were isolated 4, 7, and 21 days after SAH in dogs, and Ca++ channel currents were recorded in 10-mmol/L barium. Proteins for α1 subunits of L-type Ca++ channels were measured by immunoblotting and isometric tension recordings done on rings of the basilar artery.

Results

High voltage–activated (HVA) Ca++ channel currents were significantly decreased and low voltage–activated (LVA) currents increased during vasospasm 4, 7, and 21 days after SAH (p < 0.05). Vasospasm was associated with a significant decrease in the number of cells with negligible LVA current while the number of cells in which the LVA current formed greater than 50% of the maximal current increased (p < 0.01). Window currents through LVA and HVA channels were significantly reduced. All changes correlated with the severity of vasospasm. There was an increase in protein for Cav3.1 and Cav3.3 α1 subunits that comprise T-type Ca++ channels, a decrease in L-type (Cav1.2 and Cav1.3) and an increase in R-type (Cav2.3) Ca++ channel α1 subunits. Functionally, however, isometric tension studies showed vasospastic arteries still relaxed with nimodipine.

Conclusions

Voltage-dependent Ca++ channels are altered in cerebral arteries after SAH. While decreased L-type channels may account for the lack of efficacy of nimodipine clinically, there may be other reasons such as inadequate dose, effect of nimodipine on other cellular targets, and mechanisms of vasospasm other than smooth muscle contraction mediated by activation of L-type Ca++ channels.

Full access

Limitations of median nerve somatosensory evoked potential monitoring during carotid endarterectomy

Sumito Okuyama, Shinjitsu Nishimura, Yoshiharu Takahashi, Keiichi Kubota, Takayuki Hirano, Ken Kazama, Masato Tomii, Junko Matsuyama, Junichi Mizuno, Tadao Matsushima, Masataka Sato, and Kazuo Watanabe

OBJECTIVE

Hypoperfusion during carotid artery cross-clamping (CC) for carotid endarterectomy (CEA) may result in the major complication of perioperative stroke. Median nerve somatosensory evoked potential (MNSSEP) monitoring, which is an established method for the prediction of cerebral ischemia, has low sensitivity in detecting such hypoperfusion. In this study the authors sought to explore the limitations of MNSSEP monitoring compared to tibial nerve somatosensory evoked potential (TNSSEP) monitoring for the detection of CC-related hypoperfusion.

METHODS

The authors retrospectively analyzed data from patients who underwent unilateral CEA with routine shunt use. All patients underwent preoperative magnetic resonance angiography and were monitored for intraoperative cerebral ischemia by using MNSSEP, TNSSEP, and carotid stump pressure during CC. First, the frequency of MNSSEP and TNSSEP changes during CC were analyzed. Subsequently, variables related to stump pressure were determined by using linear analysis and those related to each of the somatosensory evoked potential (SSEP) changes were determined by using logistic regression analysis.

RESULTS

A total of 94 patients (mean age 74 years) were included in the study. TNSSEP identified a greater number of SSEP changes during CC than MNSSEP (20.2% vs 11.7%; p < 0.05). Linear regression analysis demonstrated that hypoplasia of the contralateral proximal segment of the anterior cerebral artery (A1 hypoplasia) (p < 0.01) and hypoplasia of the ipsilateral precommunicating segment of the posterior cerebral artery (P1 hypoplasia) (p = 0.02) independently and negatively correlated with stump pressure. Both contralateral A1 hypoplasia (OR 26.25, 95% CI 4.52–152.51) and ipsilateral P1 hypoplasia (OR 8.75, 95% CI 1.83–41.94) were independently related to the TNSSEP changes. However, only ipsilateral P1 hypoplasia (OR 8.76, 95% CI 1.61–47.67) was independently related to MNSSEP changes.

CONCLUSIONS

TNSSEP monitoring appears to be superior to MNSSEP in detecting CC-related hypoperfusion. Correlation with stump pressure and SSEP changes indicates that TNSSEP, and not MNSSEP monitoring, is a reliable indicator of cerebral ischemia in the territory of the anterior cerebral artery.

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Localized focal cortical dysplasia type II: seizure freedom with lesionectomy guided by MRI and FDG-PET

Naotaka Usui, Akihiko Kondo, Kazumi Matsuda, Hiroshi Ogawa, Takuji Nishida, Kentaro Tokumoto, Norihiko Kawaguchi, Takashi Matsudaira, Yasukiyo Araki, Masataka Fukuoka, Hirowo Omatsu, Hideyuki Otani, Tokito Yamaguchi, Katsumi Imai, and Yukitoshi Takahashi

OBJECTIVE

The authors perform thorough, noninvasive presurgical evaluations for intractable epilepsy at their center and avoid unnecessary intracranial EEG when possible. The purpose of this study was to clarify the appropriateness of their lesion-oriented surgical strategy for localized focal cortical dysplasia (FCD) type II.

METHODS

Fifty-one patients with pathologically proven localized FCD type II who were followed for at least 1 year after surgery were included. Patients with FCD type II with lobar or multilobar distribution were excluded. The results of presurgical evaluations, including thin-slice 3-T MRI, FDG-PET, and ictal SPECT, as well as surgical procedures and postoperative seizure and functional outcomes, were examined retrospectively.

RESULTS

MRI was positive in 46 (90%) of 51 patients, and FDG-PET revealed localized hypo- or hypermetabolism in 47 (92%) of 51 patients. Ictal SPECT revealed concordant hyperperfusion in 37 of 42 patients examined. Intracranial EEG was used in only 13 patients (25%), including 5 with negative MRI results and 4 with subtle MRI findings. Of the 15 patients with FCD in the vicinity of eloquent (sensorimotor and language) areas, intracranial EEG was used in 4. Lesionectomy was performed in all 51 patients. Intraoperative electrocorticography (ECoG) was performed in 8 patients, but the findings were not used to tailor the extent of resection. Postoperative seizure outcomes were Engel class I in 47 patients (92%) and Ia in 45 (88%). In the 15 patients with FCD in the vicinity of eloquent areas, 13 (87%) achieved a class I outcome. Predictive factors for favorable seizure outcome were complete resection of the MRI lesion (p = 0.006) and frontal lobe surgery (p = 0.012). Postoperative neurological deficits were noted in only 4 (27%) of 15 patients with FCD in the vicinity of eloquent areas. All 5 MRI-negative patients achieved an Engel class I outcome.

CONCLUSIONS

In most of the patients with localized FCD type II, MRI and/or FDG-PET detected the localized abnormality. Lesionectomy without intracranial EEG led to seizure freedom in most cases. Even when lesions were in the vicinity of eloquent areas, seizure and functional outcomes were favorable. Intraoperative ECoG may thus be unnecessary. Complete resection of the lesion is essential for favorable seizure outcome in MRI-positive patients. In MRI-negative patients, surgery with intracranial EEG guided by FDG-PET provided seizure-free outcomes.