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Background One of the important aims of surgery for moyamoya disease is to establish indirect revascularization. The purpose of this study was to assess the progress of the middle meningeal artery (MMA) after our novel preservation method and to evaluate the relation between direct and indirect bypass in the chronic stage. Methods A total of 24 hemispheric sides of 19 patients with moyamoya disease were included in this study. Craniotomy was performed with preservation of the MMA during the procedure, then direct bypass was carried out. The relationship between anatomic variations of the MMA and success rate of preserving the MMA during craniotomy was noted. The alteration of the MMA and superficial temporal artery (STA) diameters was then evaluated using magnetic resonance imaging, and the correlation between the MMA and the STA in the chronic stage was examined. Results In total, the MMA was preserved during craniotomy in 20 hemispheric sides (83.3%). During the 3-year follow-up period, the MMA and STA diameters were significantly increased. At 3 years after surgery, the alteration of the MMA diameter was significantly more marked in pediatric cases than in adult cases, and MMA diameter was moderately but significantly negatively correlated with STA diameter. Conclusions In moyamoya disease, the MMA could be developed as a pathway for indirect revascularization even after simple preservation, especially in pediatric patients. The progress of the MMA and the STA occurs through their synergistic interaction, and the balance might be decided based on their complementary relations in the chronic stage.

Objective A 3-dimensional temporal bone model for skull base surgical training was reconstructed via the use of a selective laser sintering technique, which is one of the 3-dimensional printing technologies. Methods The temporal bone model was created in 2 pieces to remove powder material in the mastoid air cells and to place dye into the semicircular canal and the Fallopian canal. Results The powder material was minimal, and the decisive structures were identified in color. Conclusions This artificial model will pave the way to a “new era” in surgical training and medical education.

Background Meningiomas or solitary fibrous tumors arising from the cavernous sinus (CS) are usually treated with radiosurgery to control growth. Surgical removal of cavernous tumors is indicated only for tumors extending outside the CS. However, even after adequate treatment, the tumor may exhibit recurrence or malignant transformation. We report a treatment option for recurrent meningeal tumors of the CS. Methods In 4 patients with CS tumors that exhibited regrowth after multiple operations and radiosurgery, radical removal in combination with high-flow bypass was performed, and a vascularized muscle flap was used for reconstruction. One patient had a radiation-induced atypical meningioma, 2 patients had transformed atypical meningiomas, and 1 patient had a frequently recurring solitary fibrous tumor. Results No local recurrence was observed in any patients during a follow-up period of 13–41 months. In all patients, a Karnofsky performance scale score of >80 on admission was maintained at >70 at the final follow-up evaluation. Conclusions Radical removal in combination with high-flow bypass provides favorable results and maintains quality of life in patients with recurrent CS meningeal tumors.

Melanoma is highly metastatic, but the mechanism of melanoma cell migration is still unclear. We found that melanoma cells expressed the nicotinamide adenine dinucleotide–dependent protein deacetylase SIRT1 in the cytoplasm. Cell membrane extension and migration of melanoma cells were inhibited by SIRT1 inhibitors or SIRT1 knockdown, whereas SIRT1 activators enhanced elongation of protrusion and cellular motility. In B16F1 cells, growth factor stimulation induced lamellipodium extension, a characteristic feature at the leading edge of migrating cells, and SIRT1 was found in the lamellipodium. SIRT1 inhibitor nicotinamide (NAM) or SIRT1 small interfering RNAs suppressed the lamellipodium extension by serum or platelet-derived growth factor (PDGF). The lamellipodium formation by dominant-active Rac1 was also inhibited by NAM, a SIRT1 inhibitor. NAM inhibited the accumulation of phosphorylated Akt at the submembrane by serum or PDGF. Using fluorescence resonance energy transfer, we found that NAM impaired PDGF-dependent increase in the phosphatidylinositol-3,4,5-trisphosphate level at the leading edge. NAM inhibited the abdominal metastasis of transplanted B16F1 melanoma cells in C57BL6/J mice and improved survival. Finally, SIRT1-knockdown B16F1 cells showed significantly reduced metastasis in transplanted mice compared with that in control B16F1 cells. These results indicate that SIRT1 inhibition is a strategy to suppress metastasis of melanoma cells.

Flow voids in the basal ganglia cannot always be recognized on magnetic resonance imaging, even in patients with typical moyamoya disease. In this report, flow voids in the basal ganglia and cisternal flow voids of the sylvian valley were evaluated in patients with moyamoya disease, and their diagnostic value was verified. A total of 41 consecutive patients with moyamoya disease were included in this analysis. The number of flow voids in the basal ganglia and the sylvian valley were counted on each side by 3 observers. Then the numbers of flow voids were compared between the patients with moyamoya disease and controls. The patients with moyamoya disease had a significantly higher mean number of flow voids in the basal ganglia and the sylvian valley (P < .0001); however, the number of flow voids in the basal ganglia was 0 or 1 in 69 sides (28.0%) in patients with moyamoya disease. Comparative analysis using the area under the receiver operating curve indicated that the evaluation of flow voids in the sylvian valley was significantly superior method to that in the basal ganglia (P < .0001). The cutoff value for the number of cisternal flow voids in the sylvian valley for the diagnosis of moyamoya disease was 6. Based on these findings, we recommend a definitive diagnosis of moyamoya disease should include assessment for abnormal vessels around the terminal portions of the internal carotid arteries.

The recent introduction of multidetector row computed tomography (MDCT) scanners has enabled high-resolution 3-dimensional reconstruction. The purpose of this study was to establish a method to evaluate moyamoya disease using computed tomography angiography (CTA), specifically MDCT. Twenty-four patients (48 sides total) with moyamoya disease diagnosed by magnetic resonance angiography (MRA) were evaluated by means of CTA using MDCT by 3 independent observers, and the resulting 144 sides were analyzed. CTA and MRA were compared in terms of the steno-occlusive changes exhibited in each vessel. CTA and MRA scores were assigned on the basis of the severity of occlusive changes in the internal carotid artery, middle cerebral artery, anterior cerebral artery, and posterior cerebral artery. CTA scores were significantly correlated with MRA scores (P.0001), and the 2 scores were in complete agreement in 57 sides (39.6%). The mean CTA score was significantly lower than the mean MRA score (P.0001). Compared with CTA, MRA overestimated occlusion in 115 of the 576 vessels assessed. The mean MRA score was significantly higher in the overestimation group than in the good correlation group (P.0001). CTA had a significantly higher rate of detection of moyamoya-affected vessels (P = .0001). Our data indicate that CTA using MDCT is a more reliable technique than MRA for diagnosing moyamoya disease. The ability to perform CTA quickly is a significant benefit for patients with moyamoya disease, particularly in pediatric and emergency cases.