Rapid Formation of Cerebral Microbleeds after Carotid Artery Stenting

Background: Recent studies reported that cerebral microbleeds (CMBs), i.e. small areas of signal loss on T2*-weighted gradient-echo (GE) imaging, could develop rapidly after acute ischemic stroke. We hypothesized that CMBs rapidly emerge after carotid artery stenting (CAS). Objective: We investigated the frequency of and predisposing factors for CMBs after CAS. Methods: We retrospectively examined MRI before and after CAS in 88 consecutive patients (average age: 71.7 ± 7.2 years, average rates of carotid stenosis: 72.6 ± 12.8%) who underwent CAS for carotid artery stenosis between March 1, 2009, and September 30, 2010. We defined new CMBs as signal losses that newly appeared on the follow-up GE. We examined the association of new CMBs with demographics, risk factors, and baseline MBs. Results: Among 88 patients, 18 (20.5%) had CMBs initially, and 7 (8.0%) developed new CMBs right after CAS. New CMBs appeared on the same side of CAS in all of the 7 patients. New CMBs appeared significantly more frequently in the CMB-positive group than in the CMB-negative one (22% vs. 4%, p = 0.03) on the pre-CAS MRI. Multivariate analysis also revealed that the presence of CMBs before CAS was an independent predictor of new development of CMBs after CAS (odds ratio: 8.09, 95% confidence interval: 1.39–47.1). Conclusion: CMBs can develop rapidly after CAS, especially in patients with pre-existing CMBs. Since the existence of CMBs prior to CAS suggests a latent vascular damage which is vulnerable to hemodynamic stress following CAS, particular attention should be paid to the prevention of intracerebral hemorrhage due to hyperperfusion after CAS

A novel locally operated master-slave robot system for single-incision laparoscopic surgery

Purpose: Single-incision laparoscopic surgery (SILS) provides more cosmetic benefits than conventional laparoscopic surgery but presents operational difficulties. To overcome this technical problem, we have developed a locally operated master-slave robot system that provides operability and a visual field similar to conventional laparoscopic surgery. Material and methods: A surgeon grasps the master device with the left hand, which is placed above the abdominal wall, and holds a normal instrument with the right hand. A laparoscope, a slave robot, and the right-sided instrument are inserted through one incision. The slave robot is bent in the body cavity and its length, pose, and tip angle are changed by manipulating the master device; thus the surgeon has almost the same operability as with normal laparoscopic surgery. To evaluate our proposed system, we conducted a basic task and an ex vivo experiment. Results: In basic task experiments, the average object-passing task time was 9.50 sec (SILS cross), 22.25 sec (SILS parallel), and 7.23 sec (proposed SILS). The average number of instrument collisions was 3.67 (SILS cross), 14 (SILS parallel), and 0.33 (proposed SILS). In the ex vivo experiment, we confirmed the applicability of our system for single-port laparoscopic cholecystectomy. Conclusion: We demonstrated that our proposed robot system is useful for single-incision laparoscopic surgery.ArticleMINIMALLY INVASIVE THERAPY & ALLIED TECHNOLOGIES. 23(6):326-332 (2014)journal articl

Epidemiology of uveitis (2013–2015) and changes in the patterns of uveitis (2004–2015) in the central Tokyo area: a retrospective study

Abstract Background The distribution of uveitis varies with genetic, ethnic, geographic, environmental, and lifestyle factors. Epidemiological information about the patterns of uveitis is useful when an ophthalmologist considers the diagnosis of uveitis. Therefore, it is important to identify the causes of uveitis over the years in different regions. The purposes of this study were to characterize the uveitis patients who first arrived at the University of Tokyo Hospital in 2013–2015, and to analyze the changes in the patterns of uveitis from 2004 to 2012 to 2013–2015. Methods We retrospectively identified 750 newly arrived patients with uveitis who visited the Uveitis Clinic in the University of Tokyo Hospital between January 2013 and December 2015, using clinical records. We extracted data on patient age, sex, diagnosis, anatomic location of inflammation, laboratory test results of blood and urine, and chest X-ray and fluorescein fundus angiography findings for each patient. In addition, we compared these data with those from 2004 to 2012 to analyze the changes in the patterns of uveitis. Results A definite diagnosis was established in 445 patients (59.3%). The most common diagnoses were herpetic iridocyclitis (7.5%), sarcoidosis (6.1%), Behçet’s disease (4.4%), Vogt–Koyanagi–Harada disease (4.1%), and intraocular lymphoma (4.1%). The most frequent unclassified type of uveitis was suspected sarcoidosis (22.3%). Analysis of the changes in the patterns of uveitis in the central Tokyo area from 2004 to 2012 to 2013–2015 revealed notable increasing trends of herpetic iridocyclitis and intraocular lymphoma, and increasing trends of bacterial endophthalmitis, fungal endophthalmitis, and juvenile chronic iridocyclitis. In contrast, the frequency of sarcoidosis, Behçet’s disease, and Vogt–Koyanagi–Harada disease decreased. Conclusions The patterns of uveitis changed considerably from 2004 to 2012 to 2013–2015. Continuous investigations about the epidemiology of uveitis are needed to diagnose uveitis more accurately

Re‐appraisal of the universal definition of tumor rupture among patients with high‐risk gastrointestinal stromal tumors

Abstract Aim Tumor rupture has been indicated as a risk factor for recurrence of gastrointestinal stromal tumors (GISTs). The universal definition of tumor rupture was proposed. This study evaluated whether the universal definition was more accurate in identification of GISTs with high recurrent risk than subjective judgment. Methods The study included 507 patients with high‐risk GISTs who underwent complete resection between December 2012 and December 2015. We conducted a questionnaire survey in participating institutes to re‐diagnose tumor rupture based on the universal definition according to their surgical and pathological findings. We compared the clinical outcomes of tumor rupture based on the definition to those based on the surgeon's judgment and clarified the clinical importance of the rupture. Results Sixty‐four patients were initially registered to have tumor rupture by surgeon's judgment, and it became 90 patients who had tumor rupture after reevaluation. Although there were significant differences in recurrence‐free survival (RFS) between no rupture and rupture for both initial registration and reevaluation (p = 0.002, <0.001, respectively), a significant difference in overall survival was only observed after reevaluation (p = 0.011). Tumor rupture was significantly associated with large tumor size, mixed cell type in histology, R1 resection, frequent adjuvant therapy and recurrence, but not with location, mitosis, and genotype. Adjuvant therapy more than 3 years improved RFS of patients with tumor rupture. Conclusion This study suggested that tumor rupture based on the universal definition more accurately identified GISTs with poor prognostic outcomes than the subjective judgment