A rare case of cerebral aspergillus aneurysm at the site of temporary clip application

Anterior communicating artery aneurysm was shown in a 48-year-old man who had suffered from subarachnoid hemorrhage (SAH) by cerebral angiography. Right pterional approach was performed on the 40th day after SAH. Premature ruptured occurred during aneurysmal manipulation and temporary clip (Scoville clip) was placed at the middle of the right A1 segment for fifteen minutes. the anterior communicating artery aneurysm was successfully clipped and postoperative course was uneventful. But, four days after the operation, the patient fell into coma following generalized tonic convulsion. Lumbar puncture showed fresh SAH. Consciousness recovered gradually to a lethargic state. A newly formed berry aneurysm was revealed on the righ A1 segment at the site of the temporary clip application by cerebral angiography performed on the seventh day after aneurysmal surgery. Second attack occurred on the 12th postoperative day and the patient died on the 16th day after the operation. Postmortem findings disclosed massive subarachnoid and intraventricular hemorrhage from the ruptured aneurysm at the right A1 segment. Microscopic examination of the aneurysm and the right A1 segment. microscopic examination of the aneurysm and the right A1 segment showed the extensive destruction of the artery and massive proliferation of aspergillus in the arterial wall which was prominent of its outer layer. The mechanism of the formation of the new aneurysm in this case was considered as follows: the arterial wall was primarily damaged by the temporary clip and was weakened rapidly by the invasion of aspergillus, probably producing thrombosis of the vast vasorum, hemorrhage, and necrosis in it.     

Real-time automatic extraction of lumen region and boundary from endoscopic images

A new approach to the automatic extraction of the lumen region and its boundary for gastrointestinal (GI) endoscopic images is presented. First, a quasi region of interest, the darker regions of the image, is segmented using a region splitting scheme termed progressive thresholding. The centre of mass of this segmented region acts as a seed for further processing. Then the lumen region is obtained using a region growing technique called the integrated neighbourhood search (INS). A new quad structure based technique is introduced to enhance the INS speed significantly. A back projection algorithm is suggested to optimise the search for pixels belonging to the lumen region and boundary. A boundary-thinning algorithm is also proposed to remove the redundant pixels from the lumen boundary and to generate a connected single pixel width boundary. The proposed approach does not need a priori knowledge about the image characteristics. The experimental results indicate that the proposed technique enhances the speed of conventional INS by 45.5% to 28.6% based on the lumen size varying from 22,709 pixels to 4947 pixels. The main advantage of the proposed technique is its high-speed response that facilitates real-time analysis of endoscopic images.     

Suitable image parameters and analytical method for quantitatively measuring cerebral blood flow volume with phase-contrast magnetic resonance imaging

The aim of this study was to determine suitable image parameters and an analytical method for phase-contrast magnetic resonance imaging (PC-MRI) as a means of measuring cerebral blood flow volume. This was done by constructing an experimental model and applying the results to a clinical application. The experimental model was constructed from the aorta of a bull and circulating isotonic saline. The image parameters of PC-MRI (repetition time, flip angle, matrix, velocity rate encoding, and the use of square pixels) were studied with percent flow volume (the ratio of actual flow volume to measured flow volume). The most suitable image parameters for accurate blood flow measurement were as follows: repetition time, 50 msec; flip angle, 20 degrees; and a 512 x 256 matrix without square pixels. Furthermore, velocity rate encoding should be set ranging from the maximum flow velocity in the vessel to five times this value. The correction in measuring blood flow was done with the intensity of the region of interest established in the background. With these parameters for PC-MRI, percent flow volume was greater than 90%. Using the image parameters for PC-MRI and the analytical method described above, we evaluated cerebral blood flow volume in 12 patients with occlusive disease of the major cervical arteries. The results were compared with conventional xenon computed tomography. The values found with both methods showed good correlation. Thus, we concluded that PC-MRI was a noninvasive method for evaluating cerebral blood flow in patients with occlusive disease of the major cervical arteries.     

MR findings of posterior fossa hemangioblastomas.

MR findings of five posterior fossa hemangioblastomas were reported. In the cystic type, a cyst was low intensity on T1WI and high intensity on T2WI. Mural nodule was clearly enhanced by Gd-DTPA. In the solid type, the tumor was shown as an isointense lesion on T1WI and as high intensity on T2WI, but it was markedly and homogeneously enhanced by Gd-DTPA. Multiple extremely low-intensity serpentine "flow void" signs, indicating afferent and efferent vessels, were observed within or around the tumor. These were characteristic pictures in this tumor.     

Usefulness and Pitfalls of Intraoperative Spinal Motor Evoked Potential Recording by Direct Cortical Electrical Stimulation

Summary ? Objective. The aim of this study is to investigate the usefulness and problems with spinal motor evoked potential (MEP) recording, especially the reasons for failed recording. We report our personal experience over the last 8 years in patients with lesions adjacent to the primary motor cortex. Methods. MEP records of 50 consecutive patients were retrospectively reviewed. MEP was recorded by a catheter electrode inserted in the cervical epidural space. Stimulation electrodes were placed on the cortical surface during surgery. SEP recording was also performed in 29 of 50 patients. Results. MEP was obtained in 40 cases, and SEP was recorded in all 29 cases. The central sulcus was identified in 93% of patients in whom both MEP and SEP were performed, whereas in only 86% of patients who underwent only MEP. The main reason for MEP failure were inadequate exposure of the motor cortex, pre-existing hemiparesis and technical errors. Postoperative deterioration of motor function was closely related to intra-operative MEP changes. Conclusion. MEP is a useful tool to determine the motor cortex and to predict postoperative motor function. However, precise pre-operative craniotomy planning and combination with intra-operative SEP is essential to reduce the MEP failure.     

Evaluation of Glucose Metabolism After Distal Pancreatectomy According to the Donor Criteria of the Living Donor Pancreas Transplantation Guidelines Proposed by the Japanese Pancreas and Islet Transplantation Association

Background

Living donor pancreas transplantation (LDPT) reduces the number of deaths of diabetic patients on dialysis and of candidates on the waiting lists and helps to overcome the organ shortage. Stringent criteria must be applied to minimize the risk of metabolic complications for living donors. The Japanese Pancreas and Islet Transplantation Association (JPITA) proposed LDPT guidelines in 2010. In this study, we retrospectively evaluated glucose metabolism of the patients who underwent distal pancreatectomy (DP) according to the donor criteria of the LDPT guidelines proposed by the JPITA.

Methods

Fifty-two nondiabetic patients who underwent DP were divided into 2 groups according to the donor criteria: indication group (IG, n = 14) who had age ≤ 65, hemoglobin A1c (HbA1c) < 5.9%, and body mass index (BMI) < 25 kg/m². The other patients were placed in the no indication group (NG, n = 38). Clinical data and percent resected volume (PRV) of each pancreas as determined by multi–detector row computed tomography volumetry were compared between the 2 groups.

Results

During the follow-up period (median 12 months), 14 patients (27%) developed new-onset diabetes within a median onset time of 10 months (range 3–24 months) postoperatively. No patient in the IG developed new-onset diabetes. On the other hand, 37% of the patients in the NG developed new-onset diabetes. There were significant between-group differences in changes in preoperative serum fasting glucose and HbA1c levels, whereas there were no significant between-group differences in preoperative serum albumin or body weight. Multivariate analysis identified preoperative HbA1c (odds ratio 51.6, P = .002) and PRV (odds ratio 2.07, P = .033) as independent risk factors for new-onset diabetes.

Conclusion

Living donor criteria in the LDPT guidelines proposed by the JPITA are appropriate for prevention of glucose metabolic complications in donors. Further long-term follow-up studies of living donors' metabolic function are needed to clarify the safety of the donor.