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Ryuta Saito, Toshihiro Kumabe, Yukihiko Sonoda, Masayuki Kanamori, Shunji Mugikura, Shoki Takahashi, and Teiji Tominaga

Object

The atrium of the lateral ventricle is often affected by tumors, and some patients with these tumors suffer neurological deficits, including hemiparesis after surgery. The authors of this study investigated the possible mechanisms causing the relatively high incidences of ischemic complications associated with surgery approaching the atrium of the lateral ventricle.

开云体育世界杯赔率

Clinical records and radiological images of 28 patients were retrospectively studied. These patients had their lateral ventricles opened at the atrium during the resection of gliomas as well as other nonbenign brain tumors, and were treated for gliomas at our tertiary referral center in the Tohoku district, Japan, between January 2008 and December 2010.

Results

Routine postoperative diffusion-weighted MR images obtained within 72 hours after surgery detected infarction in the periatrial/periventricular regions in 7 patients, presumably corresponding to the lateral posterior choroidal artery (LPChA) territory. Five of these 7 patients suffered neurological sequelae with varying severities. The choroid plexus at the atrium was coagulated to achieve hemostasis during the surgery in all of these patients. Detailed analysis of microangiograms revealed ventriculofugal arteries arising from the lateral ventricle. Damage of the subependymal artery that supplies the ventriculofugal arteries caused by coagulation of the choroid plexus at the atrium probably resulted in the infarction in these patients.

Conclusions

Neurosurgeons must be aware of the possibility of LPChA territory infarction during surgery in the atrial or periatrial regions caused by subependymal artery obstruction after manipulating or coagulating the choroid plexus near the atrium.

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Atsushi Kanoke, Masayuki Kanamori, Toshihiro Kumabe, Ryuta Saito, Mika Watanabe, and Teiji Tominaga

这个病人面对metachr少见onous, multicentric gliomas first manifesting as headache and nausea in 1983 when he was an 8-year-old boy. Computed tomography revealed a cerebellar tumor and the tumor was subtotally resected. The histological diagnosis was pilocytic astrocytoma, and radiation therapy to the posterior fossa and chemotherapy consisting of nimustine hydrochloride and fluorouracil were performed. In 1989, at age 14 years, the patient presented with local recurrence. He underwent gross-total resection of the tumor, and histological examination revealed that the tumor consisted of classic pilocytic astrocytoma with a biphasic pattern and a small oligodendroglioma-like component. In 2011, at age 36 years, he presented with seizure. Magnetic resonance imaging revealed a mass lesion in the right middle frontal gyrus. Gross-total resection of the tumor was performed, and the histological diagnosis was oligodendroglioma. Genetic analyses revealed amplification of theBRAFgene in both the primary cerebellar pilocytic astrocytoma and the recurrent tumor with biphasic features, as well as aBRAFV600E missense mutation in the oligodendroglioma-like component. On the other hand, theIDH1R132H mutation, instead of aberrations of theBRAFgene, was identified in the oligodendroglioma arising in the right frontal lobe. Different types of aberrations of theBRAFgene in the classic and oligodendroglioma-like component in the recurrent pilocytic astrocytoma suggest that they had different cell origins or that amplification ofBRAFwas negatively selected under the de novoBRAFV600E mutation. In addition, the aberration profiles ofIDH1andBRAF建议少突神经胶质瘤arose independent of cerebellar pilocytic astrocytoma.

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Ryuta Saito, John Bringas, Hanna Mirek, Mitchel S. Berger, and Krys S. Bankiewicz

Object.Chemotherapy is suspected of having an effect on the generation of phenotypical heterogeneity and the development of drug resistance in tumors. Recurrent gliomas feature drug resistance as well as greater invasive growth than original tumors. The authors investigated phenotypical changes in invasion observed in 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU)—resistant sublines of the 9L rat gliosarcoma.

Methods.Two established BCNU-resistant sublines, derived from 9L gliosarcoma cells by treating these cells with BCNU in vivo or in vitro, were used in the study. An in vitro examination confirmed the resistance of the cells to BCNU treatment. The cells were implanted into the striatum of Fisher 344 rats, and histological examinations were performed to compare the growth patterns of the resultant tumors. A new brain tumor model was established by implanting 9L-2 cells in Fisher 344 rats.

The 9L-2 and BTRC-19 cells displayed a distinct increase in BCNU resistance compared with the 9L cells. Both BCNU-resistant sublines developed a tumor mass with invasive margins, which is not the case with 9L tumor models. The newly developed 9L-2 tumor model demonstrated 100% tumor uptake with consistent growth patterns.

Conclusions.Cells that acquire drug resistance also demonstrated invasive growth. Because the 9L-2 and BTRC-19 cells were derived from 9L cells that had been treated with BCNU in vivo and in vitro, this change in phenotype was likely caused by the drug treatment, which may have implications for chemotherapy of gliomas. The tumor model that developed from the 9L-2 cells can be used as a model of a recurrent glioma, which features drug resistance and invasive growth.

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Ichiyo Shibahara, Ryuta Saito, Masayuki Kanamori, Yukihiko Sonoda, Sumito Sato, Takuichiro Hide, Teiji Tominaga, and Toshihiro Kumabe

OBJECTIVE

parietooccipital裂缝是一个解剖的土地mark that divides the temporal, occipital, and parietal lobes. More than 40% of gliomas are located in these three lobes, and the temporal lobe is the most common location. The parietooccipital fissure is located just posterior to the medial temporal lobe, but little is known about the clinical significance of this fissure in gliomas. The authors investigated the anatomical correlations between the parietooccipital fissure and posterior medial temporal gliomas to reveal the radiological features and unique invasion patterns of these gliomas.

开云体育世界杯赔率

The authors retrospectively reviewed records of all posterior medial temporal glioma patients treated at their institutions and examined the parietooccipital fissure. To clarify how the surrounding structures were invaded in each case, the authors categorized tumor invasion as being toward the parietal lobe, occipital lobe, isthmus of the cingulate gyrus, insula/basal ganglia, or splenium of the corpus callosum. DSI Studio was used to visualize the fiber tractography running through the posterior medial temporal lobe.

RESULTS

Twenty-four patients with posterior medial temporal gliomas were identified. All patients presented with a parietooccipital fissure as an uninterrupted straight sulcus and as the posterior border of the tumor. Invasion direction was toward the parietal lobe in 13 patients, the occipital lobe in 4 patients, the isthmus of the cingulate gyrus in 19 patients, the insula/basal ganglia in 3 patients, and the splenium of the corpus callosum in 8 patients. Although the isthmus of the cingulate gyrus and the occipital lobe are located just posterior to the posterior medial temporal lobe, there was a significantly greater preponderance of invasion toward the isthmus of the cingulate gyrus than toward the occipital lobe (p = 0.00030, McNemar test). Based on Schramm’s classification for the medial temporal tumors, 4 patients had type A and 20 patients had type D tumors. The parietooccipital fissure determined the posterior border of the tumors, resulting in a unique and identical radiological feature. Diffusion spectrum imaging (DSI) tractography indicated that the fibers running through the posterior medial temporal lobe toward the occipital lobe had to detour laterally around the bottom of the parietooccipital fissure.

CONCLUSIONS

Posterior medial temporal gliomas present identical invasion patterns, resulting in unique radiological features that are strongly affected by the parietooccipital fissure. The parietooccipital fissure is a key anatomical landmark for understanding the complex infiltrating architecture of posterior medial temporal gliomas.

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Shunsaku Goto, Takashi Izumi, Masahiro Nishihori, Tasuku Imai, Yoshio Araki, Fumiaki Kanamori, Kenji Uda, Kinya Yokoyama, and Ryuta Saito

OBJECTIVE

The protocol for antiplatelet therapy after stent-assisted coil embolization (SACE) for intracranial aneurysms is not well established. In particular, the indications for single antiplatelet therapy (SAPT) discontinuation remain controversial. The authors investigated the long-term outcomes of SAPT discontinuation after SACE among patients at a single institution.

开云体育世界杯赔率

Patients who underwent SACE during the period from 2010 to 2020 and who were followed up for > 1 year were included in this study. The delayed ischemic and hemorrhagic complication rates were examined during follow-up. Moreover, the risk factors of antiplatelet therapy reduction or discontinuation and the outcomes of SAPT discontinuation were examined.

RESULTS

In total, 240 patients were included in the analysis. The average patient age was 60.3 years, and the average follow-up period was 46.7 months. Nine (3.8%) patients presented with symptomatic delayed ischemic complication, and 3 (1.3%) patients experienced a decline in modified Rankin Scale score. The stent configuration (T- or Y-stent) was the only risk factor associated with delayed ischemic complication (p < 0.001). SAPT was discontinued in 147 (71.7%) of 205 patients who were followed up for > 2 years, and no ischemic complications were observed.

CONCLUSIONS

It is safe to discontinue SAPT in patients without ischemic complications and with stable intraaneurysmal signals on MRA 2 years after SACE. The T- or Y-stent is a high-risk factor for delayed ischemic complications, and antiplatelet therapy reduction or discontinuation should be cautiously considered.

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Ryuta Saito, Toshihiro Kumabe, Mika Watanabe, Hidefumi Jokura, Makoto Shibuya, Yoichi Nakazato, and Teiji Tominaga

✓作者一个21岁的男子提出报告nted with a low-grade fibromyxoid sarcoma primarily located in the right parietal lobe with diffuse infiltration. The low-grade fibromyxoid sarcoma is a rare sarcoma of the deep soft tissue that is characterized as an indolent but metastasizing soft-tissue neoplasm with a deceptively benign histological appearance. Only one case of intracranial origin has been previously reported in the literature. A high rate of local recurrence and eventual metastasis has been demonstrated for this tumor in deep soft tissue. Similarly, the patient in the present case suffered recurrence 6 times; he underwent treatment by surgical removal 4 times, Gamma Knife surgery twice, and local radiation therapy once during the 7-year follow-up period. The tumor is still under control without any evidence of extracranial metastasis. To the authors' knowledge, this is the first case report that discusses the clinical course of this rare disease in detail.

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Yui Mano, Toshihiro Kumabe, Ichiyo Shibahara, Ryuta Saito, Yukihiko Sonoda, Mika Watanabe, and Teiji Tominaga

Dysembryoplastic neuroepithelial tumors (DNETs) have conventionally been regarded as benign and stable tumors and considered curable with surgery without adjunctive therapy. Recently, recurrent DNETs with or without malignant transformation have been described. The authors report 2 unusual cases of DNET: 1) an enlarging lesion that developed an enhancing component over the natural course of 4 years, and 2) a recurrent DNET that developed an enhancing component 10–11 years after gross-total resection. The patient in the first case was treated with subtotal resection and adjuvant radiochemotherapy; histological examination of the tumor led to the diagnosis of DNET, WHO Grade I, for the nonenhancing component and anaplastic oligodendroglioma, WHO Grade III, for the enhancing component. The patient in the second case was treated with repeat gross-total resection; the original tumor had been histologically diagnosed as DNET, and the nonenhancing and enhancing components of the recurrent tumor were diagnosed as simple and complex forms of DNET, respectively. These and previous reports suggest an aggressive subtype of DNETs. If follow-up MRI reveals progressive behavior, resection should be performed without delay. Additional radiochemotherapy is needed if the histological diagnosis demonstrates malignant transformation.

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Tomohiro Kawaguchi, Toshihiro Kumabe, Ryuta Saito, Masayuki Kanamori, Yoji Yamashita, Yukihiko Sonoda, and Teiji Tominaga

Object

Maximized tumor resection and minimized surgical morbidity are extremely important in the treatment of children with malignant neuroepithelial tumors. However, the indications for repeat surgery for these tumors remain unclear. The present study investigated the clinical significance and limitations of repeat resection for these tumors.

开云体育世界杯赔率

This study included 61 consecutive pediatric patients with malignant neuroepithelial tumor, histologically diagnosed as WHO Grades III and IV. All patients were initially treated between January 1997 and March 2011 and had follow-up of more than 2 years. The number of surgeries, presence of leptomeningeal dissemination, survival, WHO grade, and Eastern Cooperative Oncology Group performance status before and after surgery were retrospectively reviewed.

Results

Repeat resections were performed for 21 patients (34.4%). Eastern Cooperative Oncology Group performance status was not aggravated by surgery, even after multiple operations. The 5-year survival rates of patients who received single and repeat surgery were 58.6% and 38.7%, respectively (p = 0.12). The mean interval between initial surgery and leptomeningeal dissemination detection was 331 ± 108 days in the single-surgery group and 549 ± 122 days in the repeat-surgery group (p = 0.19). The median survival time after leptomeningeal dissemination was 580 days in the single-surgery group and 890 days in the repeat-surgery group (p = 0.74).

Conclusions

Repeat resection with minimized surgical morbidity is an effective method to achieve better local control of pediatric malignant neuroepithelial tumors. Leptomeningeal dissemination was a leading cause of death, but repeat surgery did not increase the frequency of death.

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Toshiki Endo, Yushi Fujii, Shin-ichiro Sugiyama, Rong Zhang, Shogo Ogita, Kenichi Funamoto, Ryuta Saito, and Teiji Tominaga

OBJECT

Convection-enhanced delivery (CED) is a method for distributing small and large molecules locally into the interstitial space of the spinal cord. Delivering these molecules to the spinal cord is otherwise difficult due to the blood-spinal cord barrier. Previous research has proven the efficacy of CED for delivering molecules over long distances along the white matter tracts in the spinal cord. Conversely, the characteristics of CED for delivering molecules to the gray matter of the spinal cord remain unknown. The purpose of this study was to reveal regional distribution of macromolecules in the gray and white matter of the spinal cord with special attention to the differences between the gray and white matter.

开云体育世界杯赔率

Sixteen rats (F344) underwent Evans blue dye CED to either the white matter (dorsal column, 8 rats) or the gray matter (ventral horn, 8 rats) of the spinal cord. The rates and total volumes of infusion were 0.2 μl/min and 2.0 μl, respectively. The infused volume of distribution was visualized and quantified histologically. Computational models of the rat spinal cord were also obtained to perform CED simulations in the white and gray matter.

RESULTS

The ratio of the volume of distribution to the volume of infusion in the gray matter of the spinal cord was 3.60 ± 0.69, which was comparable to that of the white matter (3.05 ± 0.88). When molecules were injected into the white matter, drugs remained in the white matter tract and rarely infused into the adjacent gray matter. Conversely, when drugs were injected into the gray matter, they infiltrated laterally into the white matter tract and traveled longitudinally and preferably along the white matter. In the infusion center, the areas were larger in the gray matter CED than in the white matter (Mann-Whitney U-test, p < 0.01). In computational simulations, the aforementioned characteristics of CED to the gray and white matter were reaffirmed.

CONCLUSIONS

在脊髓灰质和白质distinct characteristics of drug distribution by CED. These differences between the gray and white matter should be taken into account when considering drug delivery to the spinal cord. Computational simulation is a useful tool for predicting drug distributions in the normal spinal cord.

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Ryuta Saito, Yukihiko Sonoda, Toshihiro Kumabe, Ken-ichi Nagamatsu, Mika Watanabe, and Teiji Tominaga

This 13-year-old boy with a history of cranial irradiation for the CNS recurrence of acute lymphocytic leukemia developed a glioblastoma in the right cerebellum. Resection and chemo- and radiotherapy induced remission of the disease. However, recurrence was noted in the brainstem region 8 months later. Because no effective treatment was available for this recurrent lesion, the authors decided to use convection-enhanced delivery (CED) to infuse nimustine hydrochloride. On stereotactic insertion of the infusion cannula into the brainstem lesion, CED of nimustine hydrochloride was performed with real-time MR imaging to monitor the co-infused chelated gadolinium. The patient's preinfusion symptom of diplopia disappeared after treatment. Follow-up MR imaging revealed the response of the tumor. The authors report on a case of recurrent glioblastoma infiltrating the brainstem that regressed after CED of nimustine hydrochloride.

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