Primary Central Nervous System Lymphoma in a Patient with Down Syndrome.

Intracranial tumors are rare in persons with Down syndrome. Although germ cell tumors and gliomas have been reported in Down syndrome, primary central nervous system lymphoma (PCNSL) has not. We report a case of PCNSL in a 48-year-old man with Down syndrome and no history of malignant tumors. He visited our hospital for evaluation of left hemiparesis and gait disturbance. A thorough examination revealed brain tumors, and analysis of a biopsy specimen of the tumor confirmed a diagnosis of PCNSL. The final pathological diagnosis was diffuse large B-cell lymphoma of the central nervous system. Chemotherapy with rituximab, methotrexate, procarbazine, and vincristine was administered, and whole-brain irradiation was planned in conjunction with chemotherapy. It is unclear whether chromosomal abnormalities related to Down syndrome were involved in the development of PCNSL. Further molecular biological analysis may clarify the mechanism of combined Down syndrome and PCNSL.

Antitumor effect of memantine is related to the formation of the splicing isoform of GLG1, a decoy FGF­binding protein.

Drug repositioning is a strategy for repurposing the approved or investigational drugs that are outside the scope of the original medical indication. Memantine is used as a non­competitive N­methyl­D­aspartate receptor antagonist to prevent glutamate­mediated excitotoxicity in Alzheimer's disease, and is one of the promising agents which is utilized for the purpose of cancer therapy. However, the association between memantine and Golgi glycoprotein 1 (GLG1), an intracellular fibroblast growth factor receptor, in cancers has not yet been clarified. The present study analyzed the expression and location of GLG1 in tumor cells treated with memantine. Memantine was found to suppress the growth of malignant glioma and breast cancer cells in a concentration­dependent manner. The mRNA expression of GLG1 was upregulated in a concentration­dependent manner, and the splicing variant profiles were altered in all cell lines examined. The results of western blot analysis revealed an increase in the full­length and truncated forms of GLG1. Moreover, GLG1 spread in the cytosol of memantine­treated cells, whereas it localized in the Golgi apparatus in control cells. Since GLG1 functions as a decoy FGF receptor, the modulation of GLG1 may prove to be one of the mechanisms underlying the cancer­suppressive effects of memantine.

Preliminary Clinical Surgical Experience with Temporary Simultaneous Use of an Endoscope during Exoscopic Neurosurgery: An Observational Study.

The use of an endoscope in exoscopic transcranial neurosurgery for skull-base lesions has not yet been investigated. Thus, this study aimed to investigate the advantages, disadvantages, and safety of "simultaneous temporary use of an endoscope during exoscopic surgery" (exo-endoscopic surgery (EES)). Consecutive exo-endoscopic surgeries performed by experienced neurosurgeons and assistants were analyzed. Surgical complications and time were compared with previous consecutive microsurgeries performed by the same surgeon. A questionnaire survey was conducted on 16 neurosurgeons with experience in both "temporary simultaneous use of endoscope during microscopic surgery" (micro-endoscopic surgery (MES)) and EES. EES was performed in 18 of 76 exoscopic surgeries, including tumor removal (n = 10), aneurysm clipping (n = 5), and others (n = 3). There were no significant differences in operative time, anesthesia time, or complications from microsurgery by the same operator. According to the questionnaire survey results, compared with MES, EES had a wider field of view due to its lack of an eyepiece, was easier when loading and unloading instruments into and out of the surgical field, and was more suitable for the simultaneous observation of two fields of view. Overall, 79.2% of surgeons indicated that EES may be better suited than MES to simultaneously observe two fields of view.

Snowfall reduces the risk of chronic subdural hematoma onset: Analysis of an administrative database in Japan.

BACKGROUND: Chronic subdural hematoma (CSDH) is a frequently observed disease in neurosurgical practice. Although first snowfall has been considered to increase the onset of CSDH, few reports have assessed the relationship between snowfall and CSDH. In this study, we aimed to investigate the relationship between CSDH onset and first snowfall events. METHODS: This retrospective study was based on the Japanese Diagnosis Procedure Combination inpatient database from July 1, 2010, to March 31, 2016, and on the global observation of snowfall events in Japan obtained from the Japan Meteorological Agency. We used a binomial approximation to evaluate the average number of CSDH patients after first snowfall events compared with that before first snowfall events. We calculated the odds ratio of CSDH onset on the first snowfall. RESULTS: We identified 8526 CSDH patients from the database. A total of 5573 (65.4%) were observed before first snowfall events, and 2953 (34.6%) after first snowfall events. The first snowfall of winter was significantly associated with a reduction in the occurrence of CSDH (odds ratio, 0.53; 95% confidence interval; 0.51-0.55). In subgroup analysis, only the first snowfall in October was not associated with reduction in the occurrence of CSDH. CONCLUSION: First snowfall events did not affect the onset of CSDH in Japan.

Ultrasound Modulates Fluorescence Strength and ABCG2 mRNA Response to Aminolevulinic Acid in Glioma Cells.

BACKGROUND: 5-Aminolevulinic Acid (5-ALA) photodiagnosis (PD) is an effective method to detect residual tumors during glioma surgery. However, fluorescence strength differs in malignant gliomas, and false-negative fluorescence may result in tumor residue. We investigated the effect of ultrasound on the intracellular level of protoporphyrin IX (PpIX) and expression level of ATP-binding cassette transporter 2 (ABCG2), which is thought to act as a membrane efflux pump of PpIX from cytosol. METHODS: The malignant glioma cell lines SNB19, U87MG, and T98G were used for in vitro experiments. Cultured cells underwent ultrasound irradiation (1 MHz, 3 W/cm2, duty cycle 10%) after administration of 5-ALA, and morphological changes in tumor cells were observed. PpIX levels and ABCG2 expression were evaluated. RESULTS: The glioma tumor cells showed transient morphological changes and detachment from the culture dish; however, most cells survived and reverted to their original morphology within 6 hours. PpIX expression levels increased in glioma cells after ultrasound irradiation, and the increase was earlier and greater than that for 5-ALA alone. ABCG2 expressions increased after 5-ALA administration but were lower in ultrasound-irradiated glioma cells. CONCLUSIONS: Ultrasound irradiation of malignant gliomas contributes to stronger 5-ALA-induced fluorescence by elevating intracellular PpIX levels. Suppression of ABCG2 expression by ultrasound may contribute to PpIX accumulation in glioma cells.

Occipital lobe epilepsy was presented in a patient with intracerebral schwannoma: a case report and literature review.

Schwannoma arising within brain parenchyma is a rare scenario. So far, only 70 cases were reported. We reported a case of intracerebral schwannoma presented with occipital lobe epilepsy, which has never been reported before. A 19-year-old man suffered from intermittent blurred vision and headache. Neuroradiological findings showed a left occipital lesion with cystic and solid components. Histological and electron micrograph features confirmed the diagnosis of schwannoma after the tumor was totally removed. The theories and literature related to this case were reviewed and the possible developmental origin was discussed. We found that this kind of schwannoma is more often in adolescent and young adults.

Preliminary Clinical Microneurosurgical Experience With the 4K3-Dimensional Microvideoscope (ORBEYE) System for Microneurological Surgery: Observation Study.

BACKGROUND: The exoscope has been reported as a novel neurosurgical instrumentation in clinical practice. OBJECTIVE: To investigate the possibility that ORBEYE (OE), a novel instrument that excludes eyepiece lenses and allows for microsurgery by observation of the 4K3D monitor, could replace microscopes. METHODS: We report 22 clinical cases by 5 experienced neurosurgeons and the comparative results of training 10 residents. An observation study with questionnaire survey was conducted on usability. Twelve items including image quality, eyestrain, and function of the arm were evaluated. RESULTS: The following 22 clinical procedures were conducted: surgery for intracranial hemorrhage (n = 2) and brain tumor (n = 8), laminectomy (n = 3), aneurysm clipping (n = 3), vascular anastomosis (n = 2), carotid endarterectomy (n = 2), and nerve decompression (n = 1). No complications were observed. The fluorescent study, including indocyanine-green and 5-aminolevunic acid, allowed for clear depiction on the 4K monitor. The surgeon could operate in a comfortable posture. Similar to the microscope, it was possible to change the optical and viewing axes with the OE, but the OE was switched to the microscope or endoscope in hematoma removal and pituitary surgery. Residents judged that eyestrain was strong (P = .0096). Experienced neurosurgeons acting as assistants judged that the scope arm's range of movement was narrow (P = .0204). Sixty percent of residents judged that the OE was superior to the microscope. CONCLUSION: Although based on limited experience, it was not possible to substitute the microscope with the OE in all operations; however, the OE surpasses the microscope in terms of ergonomic features.

Prediction of recovery from supplementary motor area syndrome after brain tumor surgery: preoperative diffusion tensor tractography analysis and postoperative neurological clinical course.

OBJECTIVE Previous studies have suggested a correlation between interhemispheric sensorimotor networks and recovery from supplementary motor area (SMA) syndrome. In the present study, the authors examined the hypothesis that interhemispheric connectivity of the primary motor cortex in one hemisphere with the contralateral SMA may be important in the recovery from SMA syndrome. Further, they posited that motor cortical fiber connectivity with the SMA is related to the severity of SMA syndrome. METHODS Patients referred to the authors' neurological surgery department were retrospectively analyzed for this study. All patients with tumors involving the unilateral SMA region, without involvement of the primary motor area, and diagnosed with SMA syndrome in the postoperative period were eligible for inclusion. Preoperative diffusion tensor imaging tractography (DTT) was used to examine the number of fiber tracts (NFidx) connecting the contralateral SMA to the ipsilateral primary motor area via the corpus callosum. Complete neurological examination had been performed in all patients in the pre- and postoperative periods. All patients were divided into two groups: those who recovered from SMA syndrome in ≤ 7 days (early recovery group) and those who recovered in ≥ 8 days (late recovery group). Differences between the two groups were assessed using the Student t-test and the chi-square test. RESULTS Eleven patients (10 men, 1 woman) were included in the study. All patients showed transient postoperative motor deficits because of SMA syndrome. Tractography data revealed NFidx from the contralateral SMA to the ipsilateral primary motor area via the corpus callosum. The mean tumor volume (early 27.87 vs late 50.91 cm3, p = 0.028) and mean NFidx (early 8923.16 vs late 4726.4, p = 0.002) were significantly different between the two groups. Fisher exact test showed a significant difference in the days of recovery from SMA syndrome between patients with an NFidx > 8000 and those with an NFidx < 8000. CONCLUSIONS Diffusion tensor imaging tractography may be useful for predicting the speed of recovery from SMA syndrome. To the authors' knowledge, this is the first DTT study to identify interhemispheric connectivity of the SMA in patients with brain tumors.

MyD88 Mutation in Elderly Predicts Poor Prognosis in Primary Central Nervous System Lymphoma: Multi-Institutional Analysis.

BACKGROUND: Recent genetic analysis of primary central nervous system lymphoma (PCNSL) showed that the MyD88 L265P mutation, which is related to NF-κB signaling, was a genetic hallmark for PCNSL; thus it could serve as a genetic marker for diagnosis and a potential target for molecular therapy. However, the role of the MyD88 mutation in PCNSL has not been defined. In this study, we investigated the role of the MyD88 mutation and clinical features of PCNSL-treated patients at several institutions to determine its significance as a prognostic factor. METHODS: Forty-one PCNSL (diffuse large B-cell type) patients from 8 institutions were included in this study. Their median age was 68 years; median follow-up was 26.7 months; median overall survival was 26.7 months; and their 1-year, 3-year, and 5-year survival rates were 75.6%, 58.5%, and 43.9%, respectively. Deoxyribonucleic acid was extracted from frozen tissue, and the MyD88 L265P mutation was evaluated by polymerase chain reaction and direct sequencing. RESULTS: The MyD88 L265P mutation was found in 61.0% (25/41) of cases. Kaplan-Meier analysis revealed that neither MyD88 L265P mutation nor age >65 years alone significantly predicted overall survival relative to MyD88 wild type and age <65. The MyD88 L265P mutation was predominantly present in patients aged >65 years. Among age >65 patients, the MyD88 L265P mutation portended a worse overall survival compared with the MyD88 wild type (11.5 vs. 56.2 months P < 0.04). CONCLUSION: The MyD88 L265P mutation predicted a poor prognosis in elderly PCNSL patients. A new tailor-made treatment strategy might be needed for these patients.

An intraoperative motor tract positioning method in brain tumor surgery: technical note.

Intraoperative 3D recognition of the motor tract is indispensable to avoiding neural fiber injury in brain tumor surgery. However, precise localization of the tracts is sometimes difficult with conventional mapping methods. Thus, the authors developed a novel brain mapping method that enables the 3D recognition of the motor tract for intrinsic brain tumor surgeries. This technique was performed in 40 consecutive patients with gliomas adjacent to motor tracts that have a risk of intraoperative pyramidal tract damage. Motor tracts were electrically stimulated and identified by a handheld brain-mapping probe, the NY Tract Finder (NYTF). Sixteen-gauge plastic tubes were mounted onto the NYTF and inserted in the estimated direction of the motor tract with reference to navigational information. Only the NYTF was removed, leaving the plastic tubes in their places, immediately after muscle motor evoked potentials were recorded at the minimum stimulation current. Motor tracts were electrically identified in all cases. Three-dimensional information on the position of motor tracts was given by plastic tubes that were neurophysiologically placed. Tips of tubes showed the resection limit during tumor removal. Safe tumor resection with an arbitrary safety margin can be performed by adjusting the length of the plastic tubes. The motor tract positioning method enabled the 3D recognition of the motor tract by surgeons and provided for safe resection of tumors. Tumor resections were performed safely before damaging motor tracts, without any postoperative neurological deterioration.

[A Case of Meralgia Paresthetica Treated with Neurolysis].

A 60-year-old woman presented with a 1-year history of pain and numbness in the left anterolateral thigh. The symptoms aggravated on walking and standing. Her visual analogue scale(VAS)score was 7.1/10. Tinel's like sign was positive over the lateral femoral cutaneous nerve(LFCN), in the inguinal ligament region. LFCN block at the trigger point, in the inguinal ligament, resulted in relief of the symptoms and we diagnosed meralgia paresthetica(MP), which is the entrapment neuropathy of the LFCN. Initially, we performed observation therapy with oral medication and LFCN blocks. However, these treatments failed to relieve the symptoms. Therefore, we performed neurolysis with a microscope under local anesthesia. The symptoms improved immediately after surgery and her VAS score of thigh symptom improved from 7.1 to 1.9 after 3 months. Conservative and surgical treatment for MP generally yield good outcome and we should pay attention to the MP as a differential diagnosis for thigh numbness and pain.

Teflon granuloma after microvascular decompression for hemifacial spasm: a case report and literature review.

Teflon has been commonly used as a surgical material. In particular, Teflon has been considered suitable for microvascular decompression of cranial nerves, as it is a stable, inert substance that does not resorb or migrate. Giant cell foreign body reactions after microvascular decompression (MVD) have been reported, but this rare complication has not been well recognized. Here, we report one case of Teflon granuloma that occurred 4 years after MVD for hemifacial spasm. We discuss the cause, histopathological analysis, particular MVD surgical methods, and management of Teflon granuloma.