Satoshi Ihara

Multiple intracranial arterial stenoses around the circle of Willis in association with Graves' disease: report of two cases.

OBJECTIVE AND IMPORTANCEThe association of Graves’ disease with multiple intracranial arterial stenoses is rare. CLINICAL PRESENTATIONWe report on two Japanese women who experienced the concurrence of Graves’ disease and cerebral ischemia attributable to multiple intracranial arterial stenoses around the circle of Willis. Clinically, these patients demonstrated hyperthyroidism, goiter, ophthalmopathy, and ensuing ischemic strokes. Cerebral angiography demonstrated multiple intracranial arterial stenoses around the circle of Willis in both cases. These cases did not meet the full diagnostic criteria for moyamoya disease, in that there were no abnormal, net-like, collateral vessels, but the other clinical and angiographic findings were consistent with this condition. INTERVENTIONAfter normalization of their hormonal conditions, the patients underwent cerebral revascularization procedures. Both patients achieved excellent recoveries and returned to normal daily life after treatment. CONCLUSIONMultiple intracranial arterial stenoses and Graves’ disease may occur simultaneously. Such cases may offer new insights into the pathogenesis of these two conditions. It is important to study more patients with this dual condition, to obtain more evidence of the relationship between genetic and immunogenic backgrounds.

New classification of spinal lipomas based on embryonic stage

OBJECTIVE Spinal lipomas are generally thought to occur as a result of failed primary neurulation. However, some clinical features cannot be explained by this theory. The authors propose a novel classification of spinal lipomas based on embryonic changes seen during primary and secondary neurulation. METHODS A total of 677 patients with occult spinal dysraphism underwent 699 surgeries between August 2002 and May 2015 at the National Center for Child Health and Development and Tokyo Metropolitan Childrens Medical Center. This group of patients had 378 spinal lipomas, including 119 conus spinal lipomas, 27 lipomyelomeningoceles, and 232 filum lipomas, which the authors classified into 4 types based on neural tube formation during embryonic development. Type 1 is defined as pure primary neurulation failure; Type 2 ranges from primary to secondary neurulation failure; Type 3 consists of secondary neurulation failure (early phase); and Type 4 is defined as secondary neurulation failure (late phase). The authors also review embryogenesis in secondary neurulation and analyze the clinical utility of the new classification. RESULTS There were 55 Type 1 spinal lipomas, 29 Type 2, 62 Type 3, and 232 Type 4. All filum lipomas fell into the Type 4 spinal lipoma category. Association with anorectal and/or sacral anomalies was seen in none of the Type 1 cases, 15 (52%) of Type 2, 35 (56%) of Type 3, and 31 (13%) of Type 4. Urogenital anomalies were observed in none of the Type 1 or Type 2 cases, 1 (2%) of Type 3, and 28 (12%) of Type 4. Anomaly syndromes were present in none of the Type 1 cases, 6 (21%) of Type 2, 3 (5%) of Type 3, and 16 (7%) of Type 4. Associated anomalies or anomaly syndromes were clearly observed only for Type 2-4 spinal lipomas encompassing failed secondary neurulation. Radical resection was feasible for Type 1 spinal lipomas. CONCLUSIONS Secondary neurulation of the spinal cord gives rise to the conus medullaris and filum terminale, which are often involved in spinal lipomas. Formation of spinal lipomas seems to be a continuous process overlapping primary and secondary neurulation in some cases. Association with other anomalies was higher in Type 2-4 spinal lipomas, which included failed secondary neurulation, than in Type 1 lipomas, with failed primary neurulation. On the other hand, radical resection was indicated for Type 1, but not for Type 2, spinal lipomas. The new classification of spinal lipomas based on embryonic stage has the potential for clinical use and agrees well with both clinical and surgical findings. The classification proposed here is still preliminary. Further studies and verification are necessary to establish its clinical utility.

Risk factors for the occurrence of spina bifida (a case-control study) and the prevalence rate of spina bifida in Japan.

BACKGROUND The Japanese government recommended in 2000 that women planning pregnancy should take 400 μg of folic acid daily to decrease the risk of having an infant with spina bifida. We aimed to identify risk factors for the occurrence of spina bifida and to evaluate how the prevalence rate has altered over the past 3 decades. METHODS Subjects comprised 360 women who gave birth to spina bifida-affected offspring and 2333 women who gave birth to offspring without spina bifida between 2001 and 2012. A self-administered questionnaire was used to collect data, which were analyzed by multiple logistic regression models. The prevalence rate of spina bifida was obtained through data provided by international and domestic organizations. RESULTS Four variables were significantly associated with the increased risk of having newborns afflicted with spina bifida: not taking folic acid supplements (odds ratios [OR], 2.50; 95% confidence interval [CI], 1.72-3.64), presence of spina bifida patients within third-degree relatives (OR, 4.26; 95% CI, 1.12-16.19), taking anti-epileptic drugs without folic acid (OR, 20·20; 95% CI, 2.06-198.17), and low birth weight in the newborns ≤ 2500 g (OR, 4.21; 95% CI, 3.18-5.59). The prevalence rate of spina bifida has remained 5 to 6 per 10,000 total births and has not shown any decreasing trend over the past 11 years. CONCLUSION Four risk factors were identified among Japanese women. Because recommendations and information have not decreased the occurrence of spina bifida, the Japanese government should implement mandatory food fortification.

Neurosurgical Management of Childhood Spasticity: Functional Posterior Rhizotomy and Intrathecal Baclofen Infusion Therapy

A paradigm shift is currently ongoing in the treatment of spasticity in childhood in Japan. Functional posterior rhizotomy (FPR), which was first introduced to Japan in 1996, is best indicated for children with spastic cerebral palsy, regardless of the clinical severity of spasticity. Surgery is generally carried out in the cauda equina, where the posterior root is separated from the anterior one, and neurophysiological procedures are used to judge which nerve root/rootlet should be cut. The outcome of FPR is favorable for reducing spasticity in the long-term follow-up. Intrathecal baclofen (ITB) treatment for childhood spasticity was approved in 2007 in Japan and the number of children undergoing ITB pump implantation has been gradually increasing. ITB treatment is best indicated for children with severe spasticity, especially those with dystonia, regardless of the pathological background. Since it is a surgery performed to implant foreign bodies, special attention should be paid to avoid perioperative complications such as CSF leakage, meningitis, and mechanical failure. Severely disabled children with spasticity would benefit most from ITB treatment. We would especially like to emphasize the importance of a strategic approach to the treatment of childhood spasticity. The first step is to reduce spasticity by FPR, ITB, and botulinum toxin injection. The second step is to aim for functional improvement after controlling spasticity. Traditional orthopedic surgery and neuro-rehabilitation form the second step of treatment. The combination of these treatments that allows them to complement each other is the key to a successful treatment of childhood spasticity.

Dual-port technique in navigation-guided endoscopic resection for intraparenchymal brain tumor

Background: In navigation-guided endoscopic surgery performed via a single port, the interference of surgical instruments often disturbs the resection and hemostasis. Case Description: With regard to this, we designed a dual-port technique for navigation-guided endoscopic surgery in a 62-year-old man, with intraparenchymal anaplastic astrocytoma. Two transparent sheaths with Nelaton tubes were inserted in the front of the target lesion via an infinity-shaped burr hole, under the control of the navigation system. The lesion was removed partially using a rigid endoscope and several surgical tools through the bilateral ports. Using the new method, it was convenient to perform hemostasis with bipolar coagulation and aspiration, without any interference from the surgical instruments during the surgery. Conclusion: The offered dual-port technique may be included in surgery planning for elderly patients or patients in particular conditions, with intraparenchymal brain tumors.