[Basic and Advanced Techniques of Anastomosis in Deep Surgical Fields:STA-SCA Anastomosis].

This article detailly describes the subtemporal-transtentorial STA-SCA bypass technique. Through temporal base drilling, copious cerebrospinal fluid evacuation before retraction, and sufficient retraction of the temporal lobe preserving the veins of the temporal base would be primodial to obtain an appropriate surgical field. Refrection of the tentrial free edge and identification of recipient SCA posterior to the entry point of the trochlear nerve into the cavernous sinus is a micro-anatomical key. Bilateral bayonet-type needle holders and forceps should be used not to shadow the surgical corridor with one's hands.

Predicting Inpatient Falls Using Natural Language Processing of Nursing Records Obtained From Japanese Electronic Medical Records: Case-Control Study.

BACKGROUND: Falls in hospitals are the most common risk factor that affects the safety of inpatients and can result in severe harm. Therefore, preventing falls is one of the most important areas of risk management for health care organizations. However, existing methods for predicting falls are laborious and costly. OBJECTIVE: The objective of this study is to verify whether hospital inpatient falls can be predicted through the analysis of a single input-unstructured nursing records obtained from Japanese electronic medical records (EMRs)-using a natural language processing (NLP) algorithm and machine learning. METHODS: The nursing records of 335 fallers and 408 nonfallers for a 12-month period were extracted from the EMRs of an acute care hospital and randomly divided into a learning data set and test data set. The former data set was subjected to NLP and machine learning to extract morphemes that contributed to separating fallers from nonfallers to construct a model for predicting falls. Then, the latter data set was used to determine the predictive value of the model using receiver operating characteristic (ROC) analysis. RESULTS: The prediction of falls using the test data set showed high accuracy, with an area under the ROC curve, sensitivity, specificity, and odds ratio of mean 0.834 (SD 0.005), mean 0.769 (SD 0.013), mean 0.785 (SD 0.020), and mean 12.27 (SD 1.11) for five independent experiments, respectively. The morphemes incorporated into the final model included many words closely related to known risk factors for falls, such as the use of psychotropic drugs, state of consciousness, and mobility, thereby demonstrating that an NLP algorithm combined with machine learning can effectively extract risk factors for falls from nursing records. CONCLUSIONS: We successfully established that falls among hospital inpatients can be predicted by analyzing nursing records using an NLP algorithm and machine learning. Therefore, it may be possible to develop a fall risk monitoring system that analyzes nursing records daily and alerts health care professionals when the fall risk of an inpatient is increased.

How definitive treatment affects the rupture rate of unruptured cerebral aneurysms: a competing risk survival analysis.

OBJECTIVE: To investigate the risk of bleeding from unruptured cerebral aneurysms (UCAs), previous studies have used Kaplan-Meier analyses without treating the definitive treatment as a competing risk event, which may underestimate the rupture rate. The authors analyzed the survival of patients with UCAs alongside the occurrence of aneurysm bleeding and its competing risk events. METHODS: A retrospective analysis was conducted on 722 patients diagnosed with UCAs in the period from 2000 to 2009 using an institution's electronic medical records and telephone interviews. The cumulative incidence of aneurysm rupture was examined, and factors contributing to rupture were assessed using regression analyses. RESULTS: By 2014, 19 patients had experienced aneurysm rupture, with an overall rupture rate of 0.57% per year over 3320.8 person-years. However, cumulative incidence analysis indicated that 1.3% of all patients had a rupture within 2 years after aneurysm identification, and 38.4% of the patients underwent definitive treatment in the same period. Among the patients who experienced rupture, regression analysis revealed that an aneurysm size greater than 5 mm, a location in the anterior or posterior communicating arteries, and an irregular shape contributed to aneurysm rupture, with HRs of 4.4 (95% CI 1.2-15.7), 3.5 (95% CI 1.4-8.7), and 2.1 (95% CI 0.7-6.0), respectively. CONCLUSIONS: Rupture rate analyses using the person-year or standard Kaplan-Meier method are not as informative without consideration of the competing risks. The incidence of aneurysm rupture should be presented clearly with those of competing risks.

Effectiveness of zigzag Incision and 1.5-Layer method for frontotemporal craniotomy.

BACKGROUND: In this era of minimally invasive treatment, it is important to make operative scars as inconspicuous as possible, and there is a great deal of room for improvement in daily practice. Zigzag incision with coronal incision has been described mainly in the field of plastic surgery, and its applicability for skin incision in general neurosurgery has not been reported. METHODS: Zigzag incision with 1.5-layer method was applied to 14 patients with unruptured cerebral aneurysm between April 2011 and August 2012. A questionnaire survey was administered among patients with unruptured aneurysm using SF-36v2 since April 2010. The results were compared between patients with zigzag incision and a previous cohort with traditional incision. RESULTS: There were no cases of complications associated with the operative wound. In the questionnaire survey, all parameters tended to be better in the patients with zigzag incision, and role social component score (RCS) was significantly higher in the zigzag group than in the traditional incision group (P =0.0436). CONCLUSION: Zigzag incision using the 1.5-layer method with frontotemporal craniotomy seems to represent an improvement over the conventional curvilinear incision with regard to cosmetic outcome and RCS.

Development of a new compact intraoperative magnetic resonance imaging system: concept and initial experience.

BACKGROUND: Magnetic resonance imaging (MRI) during surgery has been shown to improve surgical outcomes, but the current intraoperative MRI systems are too large to install in standard operating suites. Although 1 compact system is available, its imaging quality is not ideal. OBJECTIVE: We developed a new compact intraoperative MRI system and evaluated its use for safety and efficacy. METHODS: This new system has a magnetic gantry: a permanent magnet of 0.23 T and an interpolar distance of 32 cm. The gantry system weighs 2.8 tons and the 5-G line is within the circle of 2.6 m. We created a new field-of-view head coil and a canopy-style radiofrequency shield for this system. A clinical trial was initiated, and the system has been used in 44 patients. RESULTS: This system is significantly smaller than previous intraoperative MRI systems. High-quality T2 images could discriminate tumor from normal brain tissue and identify anatomic landmarks for accurate surgery. The average imaging time was 45.5 minutes, and no clinical complications or MRI system failures occurred. Floating organisms or particles were minimal (1/200 L maximum). CONCLUSION: This intraoperative, compact, low-magnetic-field MRI system can be installed in standard operating suites to provide relatively high-quality images without sacrificing safety. We believe that such a system facilitates the introduction of the intraoperative MRI.

Reinforcement of pericranium as a dural substitute by fibrin sealant.

BACKGROUND: For dural plasty, several kinds of substitute materials are used clinically. Among these materials, pericranium is often used as a dural substitute since it is autologous and easy to harvest. However, it is rather thin and fragile, which makes it difficult to suture onto peripheral dura mater, especially when the defect is large. OBJECTIVE: We present a simple method of reinforcing the pericranium with fibrin sealant, which facilitates easier handling and suturing of the pericranium. METHODS: Fifteen patients who underwent surgical removal of meningioma, metastatic brain tumor and glioma attached to the dura mater were included in this analysis. To close the defects, we use 'fibrin-sealed pericranium'. Herein we describe the method we employed in these cases. First, a standard skin flap is made by dissecting the subgaleal layer, leaving the periosteum on the bone. Second, fibrin sealant is evenly applied to the pericranium. Finally, the pericranium is cut along the reinforced area and dissected from the bone. The harvested pericranium is then used for closure of the dural defect. Some of these patients received further treatment as needed according to each pathology. The fibrin-sealed pericranium was examined histopathologically. RESULTS: Fibrin-sealing of pericranium made it durable enough to be handled and sutured easily. There were no significant complications or treatment failures, such as infection or CSF leakage. CONCLUSIONS: Reinforcement of the pericranium with fibrin sealant is a simple and easy method to reduce the stress of dural plasty.

Simulation of and training for cerebral aneurysm clipping with 3-dimensional models.

OBJECTIVE: With improvements in endovascular techniques, fewer aneurysms are treated by surgical clipping, and those aneurysms targeted for open surgery are often complex and difficult to treat. We devised a hollow, 3-dimensional (3D) model of individual cerebral aneurysms for preoperative simulation and surgical training. The methods and initial experience with this model system are presented. METHODS: The 3D hollow aneurysm models of 3 retrospective and 8 prospective cases were made with a prototyping technique according to data from 3D computed tomographic angiograms of each patient. Commercially available titanium clips used in our routine surgery were applied, and the internal lumen was observed with an endoscope to confirm the patency of parent vessels. The actual surgery was performed later. RESULTS: In the 8 prospective cases, the clips were applied during surgery in the same direction and configuration as in the preoperative simulation. Fine adjustments were necessary in each case, and 2 patients needed additional clips to occlude the atherosclerotic aneurysmal wall. With these 3D models, it was easy for neurosurgical trainees to grasp the vascular configuration and the concept of neck occlusion. Practicing surgery with these models also improved their handling of the instruments used during aneurysm surgery, such as clips and appliers. CONCLUSION: Using the hollow 3D models to simulate clipping preoperatively, we could treat the aneurysms confidently during live surgery. These models allow easy and concrete recognition of the 3D configuration of aneurysms and parent vessels.

Newly developed endoscopic instruments for the removal of intracerebral hematoma.

Ultra-early surgical treatment in which associated brain injury is minimized and maximal volume of hematoma is removed shortly after onset with secure hemostasis is expected to be established. We developed a transparent guiding sheath and other surgical instruments for endoscopic surgery and established a novel, ultra-early stage surgical procedure using those instruments. This procedure has the following characteristics: (a) burr hole opening under local anesthesia is possible; (b) a transparent sheath improves the visualization of the surgical field in the parenchyma and the hematoma; (c) free-hand surgery without fixing an endoscope and a sheath to a frame facilitates three-dimensional operation; (d) secure hemostasis by electric coagulation is possible; (e) relatively simple surgical instruments are easy to prepare. We have performed this procedure in 82 patients with intracerebral or intraventricular hemorrhage (44 with putaminal hemorrhage, 12 with thalamic hemorrhage, 8 with subcortical hemorrhage, 8 with cerebellar hemorrhage, 10 with intraventricular hemorrhage). Twenty-four of those patients received our treatment in the ultra-early stage (within 3 hours after onset). The mean duration of surgery was 63 minutes, the mean hematoma reduction rate was 96%, and no peri-operative hemorrhage with deterioration of symptoms and/or signs occurred. Therefore, we believe that endoscopic hematoma evacuation with our surgical procedure is a promising ultra-early stage treatment for intracerebral hemorrhage and that it may improve the long-term prognosis in patents with intracerebral hemorrhage.

Correlation of histology and molecular genetic analysis of 1p, 19q, 10q, TP53, EGFR, CDK4, and CDKN2A in 91 astrocytic and oligodendroglial tumors.

PURPOSE: The histological diagnosis of human gliomas is of great importance for estimating patient prognosis and guiding therapy but suffers from being subjective and, therefore, variable. We hypothesized that molecular genetic analysis could provide a more objective means to classify tumors and, thus, reduce diagnostic variability. EXPERIMENTAL DESIGN: We performed molecular genetic analysis on 91 nonselected gliomas for 1p, 19q, 10q, TP53, epidermal growth factor receptor, and cyclin-dependent kinase 4 abnormalities and compared with the consensus diagnoses established among four independent neuropathologists. RESULTS: There were six astrocytomas, seven anaplastic astrocytomas, 45 glioblastomas, 21 oligodendrogliomas, eight anaplastic oligodendrogliomas, three oligoastrocytomas, and one anaplastic oligoastrocytoma. Twenty-nine cases had either 1p or 19qloss of heterozygosity (LOH) while retaining both copies of 10q, of which 25 (86%) were histologically oligodendroglioma, anaplastic oligodendroglioma, oligoastrocytoma, or anaplastic oligoastrocytoma. As for the oligodendroglial tumors, unanimous agreement of the initial diagnoses was almost restricted to those cases with combined 1p/19qLOH, whereas all nine tumors without 1p loss initially received variable diagnoses. Interestingly, TP53 mutation was inversely related to 1pLOH in all gliomas (P = 0.0003) but not 19qLOH (P = 0.15). CONCLUSIONS: These data demonstrate that molecular genetic analysis of 1p/19q/10q/TP53 has significant diagnostic value, especially in detecting oligodendroglial tumors. In addition, 1pLOH and TP53 mutations in gliomas may be markers of oligodendroglial and astrocytic pathways, respectively, which may separate gliomas with the same histological diagnosis, especially oligodendroglial tumors and glioblastomas. Testing for those molecular genetic alterations would be essential to obtain more homogeneous sets of gliomas for the future clinical studies.