Cervical Ossification of Posterior Longitudinal Ligament in X-Linked Hypophosphatemic Rickets Revealing Homogeneously Increased Vertebral Bone Density

Masato Shiba,Masaki Mizuno,Keita Kuraishi,Hidenori Suzuki 대한척추외과학회 2015 Asian Spine Journal Vol.9 No.1

There is no report that describes in detail the radiological and intraoperative findings of rickets with symptomatic cervical ossification of the posterior longitudinal ligament. Here, we describe a case of X-linked hypophosphatemic rickets with cervical ossification of the posterior longitudinal ligament presenting unique radiological and intraoperative findings. The patient presented progressive tetraparesis. Magnetic resonance imaging studies revealed severe cervical spinal cord compression caused by ossification of the posterior longitudinal ligament. Computed tomography scans revealed homogeneously increased vertebral bone density. An expansive laminoplasty was performed. At surgery, homogeneously hard lamina bone was burdened in drilling and opening of the laminae. The patient’s neurological symptoms were improved postoperatively. Bony fusion of the hinges occurred postoperatively. Therefore, expansive laminoplasty could be performed for symptomatic cervical ossification of the posterior longitudinal ligament with X-linked hypophosphatemic rickets. However, unusual bone characters should be taken into consideration for careful operation during surgery.

Spinal Cord Subependymoma: A Subanalysis of the Neurospinal Society of Japan’s Multicenter Study of Intramedullary Spinal Cord Tumors

Takashi Yagi,Masaki Mizuno,Hiroto Kageyama,Kotaro Tatebayashi,Toshiki Endo,Yasuhiro Takeshima,Motoyuki Iwasaki,Ryu Kurokawa,Keisuke Takai,Misao Nishikawa,Kazutoshi Hida 대한척추신경외과학회 2023 Neurospine Vol.20 No.3

Objective: This study aimed to analyze the clinical characteristics, treatment strategies, and surgical outcomes of subependymoma patients from the 2022 Neurospinal Society of Japan multicenter intramedullary spinal cord tumor study. Methods: Twenty-six patients with spinal cord subependymoma who were included in the index study of 1,033 patients were retrospectively analyzed. Results: Mean patient age was 49.4 years. Seventeen patients were men and 9 were women. Sensory disturbance was reported in 22 patients and motor weakness in 18. Median duration of symptoms was 24 months. The tumor was eccentrically located in 19 patients (73.1%) and unilateral in 17 (65.4%). Gross total resection was achieved in 6 patients (23.1%). The same rate for ependymoma patients in the index study was significantly higher (74.8%). Median follow-up was 40.5 months (interquartile range, 18–68 months). In 2 patients who underwent only partial resection, reoperation was required owing to progression 68 and 90 months after surgery, respectively. No recurrence occurred in patients who underwent gross total resection. Five patients experienced neurological worsening after surgery. Conclusion: Although spinal cord subependymoma can be difficult to distinguish from other intramedullary spinal cord lesions before surgery, it is characterized by an indolent clinical course and eccentric location. Surgical treatment should prioritize functional preservation because the prognosis is good even after subtotal resection.

The Impact of Adjuvant Radiotherapy on Clinical Performance Status in Patients With Grade II Spinal Cord Astrocytoma – A Nationwide Analysis by the Neurospinal Society of Japan

Ryo Kanematsu,Masaki Mizuno,Tomoo Inoue,Toshiyuki Takahashi,Toshiki Endo,Seiji Shigekawa,Jun Muto,Daisuke Umebayashi,Takafumi Mitsuhara,Kazutoshi Hida,Junya Hanakita 대한척추신경외과학회 2023 Neurospine Vol.20 No.3

Objective: The impact of adjuvant radiotherapy on overall survival (OS) and progressionfree survival (PFS) of patients with grade II spinal cord astrocytomas remains controversial. Additionally, the relationship between progression and clinical deterioration after radiotherapy has not been well investigated. Methods: This study included 53 patients with grade II intramedullary spinal cord astrocytomas treated by either subtotal, partial resection or open biopsy. Their clinical performance status was assessed immediately before operation and 1, 6, 12, 24, and 60 months after surgery by Karnofsky Performance Scale (KPS). Patients with and without adjuvant radiotherapy were compared. Results: The groups with and without radiation comprised 23 and 30 patients with a mean age of 50.3 ± 22.6 years (range, 2–88 years). The mean overall disease progression rate was 47.1% during a mean follow-up period of 48.4 ± 39.8 months (range, 2.5–144.5 months). In the radiation group, 11 patients (47.8%) presented with progressive disease, whereas 14 patients (46.7%) presented with progressive disease in the group without radiation. There were no significant differences in OS or PFS among patients with or without adjuvant radiotherapy. KPS in both groups, especially radiation group, gradually decreased after operation and deteriorated before the confirmation of disease progression. Conclusion: Adjuvant radiotherapy did not show effectiveness regarding PFS or OS in patients with grade II spinal cord astrocytoma according to classical classification based on pathohistological findings.

Intramedullary Schwannoma of the Spinal Cord: A Nationwide Analysis by the Neurospinal Society of Japan

Takeshi Hara,Masaki Mizuno,Kazutoshi Hida,Toru Sasamori,Yasuyuki Miyoshi,Hisaaki Uchikado,Hiroki Ohashi,Taku Sugawara,Yasuhiro Takeshima,Yukoh Ohara,Akihide Kondo,Toshiki Endo 대한척추신경외과학회 2023 Neurospine Vol.20 No.3

Objective: This study was aimed to report the clinical characteristics of intramedullary schwannomas and discuss imaging findings and treatment strategies. Methods: The inclusion criterion was consecutive patients with intramedullary schwannomas who were surgically treated at 8 centers between 2009 and 2020. Clinical characteristics included age, sex, clinical presentation, disease duration, and follow-up period. The modified McCormick scale was used to compare the preoperative and postoperative conditions. Pre- and postoperative magnetic resonance images (MRI) of each case were analyzed. Results: The mean age of the total 11 patients at the operation was 50.2 years. The mean duration of the symptoms was 23 months, with limb paresthesia being the most common clinical presentation. The cervical spine was the most common localization level of the tumor in 6 cases. The mean follow-up duration was 49.4 months. Gross total resection (GTR) and subtotal resection (STR) was achieved in 9 and 2 cases, respectively. According to the modified McCormick scale at 6 months postoperatively, 7 cases (63.6%) had improved and 4 cases (36.3%) had unchanged grades. Typical MRI findings of the intramedullary schwannoma included ring-like enhancement, syringomyelia, cystic formation, intramedullary edema, and hemosiderin deposition. Gadolinium enhancement was homogenous in 8 cases (72.7%). The tumor margins were well demarcated in all cases. Conclusion: Intramedullary schwannoma should be considered when sharp margins and well-enhanced tumors are present at the cervical spine level and the initial symptoms are relatively mild, such as dysesthesia. When GTR cannot be achieved, STR for tumor decompression is recommended.

Current Trends in the Surgical Management of Intramedullary Tumors: A Multicenter Study of 1,033 Patients by the Neurospinal Society of Japan

Toshiki Endo,Tomoo Inoue,Masaki Mizuno,Ryu Kurokawa,Kiyoshi Ito,Shigeo Ueda,Toshihiro Takami,Kazutoshi Hida,Minoru Hoshimaru,Investigators of intramedullary spinal cord tumors in the Neurospinal Socie 대한척추신경외과학회 2022 Neurospine Vol.19 No.2

Objective: We performed a retrospective observational study to demonstrate the surgical risks and long-term prognoses of intramedullary tumors in Japan using a multicenter registry authorized by the Neurospinal Society of Japan. Methods: Data from 1,033 consecutive patients with intramedullary tumors, treated between 2009 and 2020, were collected from 58 centers. Patients with spinal lipomas or myxopapillary ependymomas were excluded. Patient characteristics, clinical presentations, imaging characteristics, treatments, and outcomes were analyzed. The modified McCormick scale was used to classify functional status. Survival was described using Kaplan-Meier curves, and multivariable logistic regression analyses were performed. Results: The mean age of the patients was 48.4 years. Data of 361 ependymomas, 196 hemangioblastomas, 168 astrocytic tumors, 160 cavernous malformations, and the remaining 126 cases including subependymomas, metastases, schwannomas, capillary hemangiomas, and intravascular B-cell lymphomas were analyzed. Twenty-two patients were undiagnosed. The mean follow-up duration was 46.1 ± 38.5 months. Gross total tumor removal was achieved in 672 tumors (65.1%). On the modified McCormick scale, 234 patients (22.7%) had worse postoperative grades at the time of discharge. However, neurological status gradually improved. At 6 months postoperatively, 251 (27.5%), 500 (54.9%), and 160 patients (17.6%) had improved, unchanged, and worsened grades, respectively. Preoperative functional status, gross total tumor removal, and histopathological type were significantly associated with mortality and functional outcomes. Conclusion: Our findings demonstrate better postoperative functional outcomes in patients with fewer preoperative neurological deficits. Degree of resection, postoperative treatments, and prognoses are closely related to the histology of intramedullary tumors.

Anisotropic Spin Excitations in Spin-Peierls CuGeO3

Kazuhiko Ikeuchi,Ryoichi Kajimoto,Fumio Mizuno,Masaki Fujita,Yasuhiro Inamura,Mitsutaka Nakamura,Kenji Nakajima,Kazuya Aizawa,Masatoshi Arai 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

We report on the investigation of spin excitations in CuGeO3 at a low temperature by usinginelastic neutron scattering on a pulsed source with a time-of-flight analysis. By observing thedispersion relation of spin excitations not only along the chain direction but also along the interchain direction, we studied spin correlations in the S = 1/2 Heisenberg chains, as well as between thechains, in detail. The results show a clear anisotropy of the magnetic excitations at a temperaturebelow the spin-Peierls transition temperature.

Comparison of the Recurrence and Surgical Outcome of Spinal Hemangioblastoma in Sporadic and Von Hippel-Lindau Diseases: A Subanalysis of a Nationwide Study by the Neurospinal Society of Japan

Yasuhiro Takeshima,Hirokazu Takami,Toshiki Endo,Masaki Mizuno,Kazutoshi Hida 대한척추신경외과학회 2023 Neurospine Vol.20 No.3

Objective: This study aimed to clarify the relationship between recurrence and the extent of resection in surgery for intramedullary spinal hemangioblastoma (sHB) and its impact on von Hippel-Lindau (vHL) disease. Methods: Data on sHB cases followed up for at least 6 months after surgery were extracted from a nationwide registry of 1,033 consecutive spinal intramedullary tumors surgically treated between 2009 and 2020, and were retrospectively categorized into a sporadic or vHL group. The diagnosis of vHL disease was made at each institution based on clinical findings. Results: A total of 168 patients (sporadic group, 101; vHL group, 67) were included in the study. Compared with the sporadic group, the vHL group had a younger onset (45.4 ± 16.8 years vs. 39.6 ± 14.1 years, p = 0.02), more preoperative motor (47.5% vs. 68.7%, p < 0.01) and gait (37.6% vs. 61.2%, p < 0.01) impairments, and more patients with worsening neurological symptoms at discharge (p = 0.02). The gross total resection (GTR) rates and the recurrence rates were not statistically different between the sporadic and the vHL groups. GTR significantly improved recurrence-free survival compared to non-GTR in all patient analysis (p < 0.01) but this trend was not observed in the sporadic group. Physical functional improvement from discharge to 6 months after surgery was observed in the sporadic group (p < 0.01) but not in the vHL group. Conclusion: A high GTR rate may sufficiently decrease susceptibility to recurrence, especially in patients with sHB with vHL. In sporadic sHB, postoperative functional improvement can be expected, and the long-term functional prognosis is favorable.

Description of the Diversity in Surgical Indication and Surgical Strategies for Primary Spinal Cord Tumors: A Nationwide Survey by the Neurospinal Society of Japan

Yasukazu Hijikata,Shigeo Ueda,Takao Yasuhara,Daisuke Umebayashi,Toshiki Endo,Toshihiro Takami,Masaki Mizuno,Kazutoshi Hida,Minoru Hoshimaru 대한척추신경외과학회 2022 Neurospine Vol.19 No.4

Objective: To assess the current management of primary spinal cord tumors (PSCTs) and determine whether and to what extent there are differences in surgical strategies for PSCTs. Methods: The Neurospinal Society of Japan conducted a survey between April 1 and 30, 2021. Certified spine surgeons were requested for information on the frequency of surgeries in 2020 and the surgical strategies adopted for each PSCTs. The following tumor histologies were focused: schwannoma, meningioma, and cauda equina tumor as extramedullary tumors; and ependymoma, hemangioblastoma, astrocytoma, and cavernoma as intramedullary tumors. The participants were divided according to their response as follows: experts, who had experienced ≥ 100 surgeries for PSCTs, and nonexperts. Results: Among 308 participants (63%), 35 (11%) were experts. The total number of PSCTs in 2020 was 802 of which 564 tumors were extramedullary and 223 were intramedullary. Schwannoma accounted for 53% of the extramedullary tumors, and ependymoma accounted for 39% of the intramedullary tumors. Surgical strategies significantly differed among both the experts and nonexperts groups. Some discrepancies in the adopted surgical strategies were observed between groups. Some of the nonexperts, and none of the experts, ruled out surgery for schwannomas (Eden type 4), astrocytomas, or cavernomas. Five nonexperts (2.2%), and none of the experts, resected the entire dura for meningiomas. Conclusion: A nationwide survey revealed that a sufficient consensus did not exist regarding surgical strategies for PSCTs. A disease-specific registry for PSCTs is necessary in academic societies.