Hiroki Mori

Endoscopic submucosal dissection of large colorectal tumors by using a novel spring-action S-O clip for traction (with video)

BACKGROUNDnEndoscopic submucosal dissection (ESD) allows en bloc resection of large GI neoplasms, regardless of their size; however, technical difficulties associated with ESD in the colorectum make it less widely applied in the treatment of tumors in this region. To address this difficulty, we designed a rubber strip-based traction device, called the S-O clip (Sakamoto-Osada clip) and reported previously that ESD with this device was effective for complete resection of large, superficial colorectal neoplasms. In this report, we describe a novel spring-action version of the S-O clip (spring S-O clip) that improves the facility of clip use during ESD of colorectal tumors.nnnOBJECTIVEnTo evaluate the efficacy and safety of the spring S-O clip for ESD of colorectal neoplasms.nnnDESIGNnCase series.nnnSETTINGnJuntendo University Hospital.nnnMAIN OUTCOME MEASUREMENTSnThe efficacy and safety of the spring S-O clip traction device during ESD of colorectal tumors.nnnRESULTSnIn 3 cases, a large, superficial neoplasm in the right side of the colon was removed safely and successfully en bloc without complication. Procedure times for the 3 cases were 44, 27, and 49 minutes, with resected specimens measuring 40, 24, and 35 mm, respectively.nnnLIMITATIONnUncontrolled study.nnnCONCLUSIONnThis limited case series demonstrates that spring S-O clip-assisted ESD is safe and effective for en bloc resection of large superficial neoplasms in the right side of the colon.

Dissociation and dispersion of claudin-3 from the tight junction could be one of the most sensitive indicators of reflux esophagitis in a rat model of the disease.

BackgroundThe aim of this study was to characterize pathological lesions of the esophageal epithelial tight junction (TJ) complex in a rat reflux esophagitis (RE) model in a search for a reliable diagnostic indicator.MethodsRats underwent an operation to induce RE, with or without rabeprazole treatment (1.0 and 10.0xa0mg/kg/day). Sham-operated rats served as a control. Fourteen days after the operation, esophagi were isolated from the rats and submitted to double-label confocal immunofluorescence microscopy, and biochemical analyses.ResultsImmunofluorescence microscopy revealed that claudins-1, -3, and -4 were located on the surfaces of epithelial cells in the normal esophagus of the control group, although there were differences in the distribution patterns between claudin-3 and claudins-1 and -4 in the epithelial layer. However, in RE, the immunoreactivity of claudin-3 on the cell surface was decreased, and it appeared instead as a faint granular pattern within the epithelial cytoplasm. Claudin-3 expression in the entire esophageal epithelium was also decreased. The expression and location of claudins-1 and -4 in epithelial cells were basically unaffected in RE. Gastric acid-induced dissociation of claudin-3 elicited instability of the epithelial TJ complex, which was confirmed by sedimentation analysis using centrifugation in a sucrose density gradient. Rabeprazole (10.0xa0mg/kg/day) attenuated these alterations.ConclusionsOur data indicate that the dispersion of claudin-3 from esophageal epithelial plasma membranes to cytoplasm and the resulting instability of the TJ complex could be one of the most specific and sensitive indicators for monitoring inflammatory and recovery processes in RE.

“Loop Clip”, a new closure device for large mucosal defects after EMR and ESD

endoscopic submucosal dissection (ESD) are indicated for the treatment of large early−stage superficial colorectal cancers. Bleeding and perforation are common complications of EMR and ESD, but clo− sure of the mucosal defect reduces the risk of complications. Hemoclips have been used for endoscopic closure of EMR defects, but they can only be used when the diameter of the defect is less than the width of the open clip. Because it is quite difficult to do, it is not common to close large mucosal defects despite the in− creased risk of bleeding and perforation. A few techniques involving closure devi− ces have been reported [1,2], but these complicated methods have not been widely employed because of the need for a 2−channel colonoscope. Therefore, we designed a new closure device for large mucosal defects, named a “loop clip”. The loop clip consists of a metal clip at− tached to a loop of nylon string (l Fig. 1). The loop clip can be passed through the instrument channel of the endoscope (l Fig. 2). After EMR and ESD, a loop clip is connected to the edge of the mucosal defect at the mid of distal side and the mid of proximal side (l Fig. 3 and 4). Afterwards, regular clips are placed individually to achieve complete closure. Complete closure of mucosal de− fects using the loop clip has been per− formed on three large mucosal defects after ESD (mean size, 39 mm). We con− firm that it was easy to close any mucosal defect completely and immediately using the loop clip. These preliminary results suggest that loop clip−assisted complete closure of mucosal defects is effective and easy to do and can be done immedi− ately. None of the patients developed fe− cal peritonitis or delayed bleeding. In the future, this method of suturing is expect− ed to become successful for immediate closure of gaping perforations.

Prospective clinical trial of traction device-assisted endoscopic submucosal dissection of large superficial colorectal tumors using the S–O clip

BackgroundEndoscopic submucosal dissection (ESD) allows en bloc resection of superficial colorectal tumors regardless of size. However, ESD is technically difficult, hazardous, and time consuming. New devices may help overcome these drawbacks. We focused on traction methods and designed a new traction device, the “S–O clip.” Its main advantage is that it allows direct visualization of the cutting line during submucosal dissection. Moreover, it can be used at any location without withdrawing the endoscope. The purpose of this study was to evaluate the efficacy and safety of traction device-assisted ESD for large colorectal tumors using the S–O clip.MethodsBetween August 2010 and December 2011, ESD was performed in 70 patients with a superficial colorectal tumor ≥20xa0mm in diameter in our department. Patients were randomized into two groups: 27 cases in the S–O clip-assisted ESD group and 23 cases in the conventional ESD group. Included in the analysis were patient’s gender and age, tumor form, size, and location, rate of en bloc resection, procedure time, presence or absence of intraoperative perforation or delayed bleeding, and pathological findings. Subgroup analysis stratified by these factors and multivariate analyses were conducted.ResultsIn the S–O clip-assisted ESD group, all 27 tumors were resected en bloc without any complications. Although a micro perforation occurred in one patient in the conventional ESD group, further surgical treatment was not required. None of the other 22 cases in the conventional ESD group experienced complications. The mean procedure time for the S–O clip-assisted ESD group was significantly shorter than for the conventional ESD group (37.4xa0±xa032.6 vs. 67.1xa0±xa044.1xa0min, pxa0=xa00.03). No significant between-group differences were found for the other factors.ConclusionOur results demonstrated that S–O clip-assisted ESD is safe and fast for en bloc resection of large superficial colorectal tumors.

Usefulness of flexible spectral imaging color enhancement for the detection and diagnosis of small intestinal lesions found by capsule endoscopy

Abstract Objective. Capsule endoscopy (CE) is an established technique for the detection and diagnosis of obscure gastrointestinal bleeding (OGIB). Flexible spectral imaging color enhancement (FICE) is a software feature of RAPID 6.5. This study assessed the value of FICE for accurate identification of red lesions during CE. Methods. We randomly selected 10 patients who underwent CE for OGIB at Juntendo University. The CE images were read by five endoscopists. Small bowel videos, which were recorded by regular CE devices (PillCam SB2, Given Imaging), were evaluated on RAPID 6.5. We standardized the reading condition to a dual view, at a speed of 20 frames/s in manual mode. This interpreted FICE-CE images obtained at settings 1–3. Both conventional and FICE images were read at random. We defined a conventional image as standard and investigated the potential of FICE in detecting small intestinal lesions by the Steel–Dwass test. Results. We considered that conventional images represented baseline (100). On this basis, detection rates for FICE images were as follows: FICE1 = 266.4 ± 33.1 (p < 0.0001); FICE2 = 255.4 ± 25.6 (p < 0.0001); and FICE3 = 117.0 ± 12.3 (p = 0.9447). Detection rates using FICE1 and FICE2 images were significantly higher than conventional CE images. FICE1 and FICE2 were more useful in detecting erosions than conventional CE (p < 0.0001) and FICE3 (p < 0.0001). Conclusions. FICE-CE has a high level of visibility by transparentizing bile or enhancing the color difference associated with reddish mucosa. We found that FICE-CE images were useful in the diagnosing of small intestinal lesions.

Evaluation of new subclassification of type VI pit pattern for determining the depth and type of invasion of colorectal neoplasm

BackgroundColorectal neoplasms with a type VI pit pattern include various lesions, such as adenomas, intramucosal cancers, and submucosal carcinomas.MethodsWe analyzed 96 colorectal neoplasms with a type VI pit pattern and identified six different variants: (1) unclear outline of the pit; (2) irregular margins of the pit; (3) narrowing of the pit; (4) ragged array of the pit; (5) high residual density of the pit; (6) abnormal branching of the pit. We examined the relationship between the appearance of each VI pit pattern and histology, including the depth of invasion.ResultsIn univariate logistic regression analysis the unclear outline, irregular margins, and narrowing of the pit were significantly associated with a submucosal (SM) invasion ≥1000xa0μm (Pxa0<xa00.01). In multivariate logistic regression analysis, unclear outline of the pit was shown to be the only significant predictor of highly invasive submucosal cancer (odds ratioxa0=xa024.20, Pxa0<xa00.0001). Regarding tumor morphology, the following were significantly associated with an SM invasion ≥1000xa0μm: in protruded type, ragged array (Pxa0=xa00.022), irregular margins of the pit (Pxa0=xa00.011), and unclear outline of the pit (Pxa0<xa00.01); in flat type, irregular margins of the pit (Pxa0<xa00.01) and unclear outline of the pit (Pxa0<xa00.01); and in the depressed type, narrowing of the pit (Pxa0=xa00.015) and unclear outline of the pit (Pxa0<xa00.01).ConclusionsSubclassification of the type VI pit pattern is useful for determining the depth of invasion of colorectal neoplasms.

Clinical feature of asymptomatic reflux esophagitis in patients who underwent upper gastrointestinal endoscopy

Background and Aim:u2002 Prevalence of gastroesophageal reflux disease (GERD) varies in regions, but few reports on clinical features and quality of life (QOL) of asymptomatic GERD exist in Japan.

Metastatic renal cell carcinoma diagnosed by capsule endoscopy and double balloon endoscopy

Summary Background Renal cell carcinoma commonly metastasizes to lung, liver, and bone. Small intestinal metastases are exceedingly rare. Case Report A 75-year-old man presented at our hospital with tarry stools. He had undergone a right nephrectomy for renal cell carcinoma (RCC) 6 years previously; in addition, he had received antiplatelet treatment for ischemic heart disease. Esophagogastroduodenoscopy, total colonoscopy, and computed tomography did not identify any cause for the gastrointestinal bleeding. He underwent capsule endoscopy (CE), which revealed an ulcerated submucosal tumor in the jejunum. We performed a double-balloon endoscopy (DBE), and histological findings identified a clear cell carcinoma. We diagnosed metastasis from the RCC. We performed a jejunectomy to resect the tumor and thus eliminate the source of the bleeding. Conclusions CE and DBE are useful diagnostic tools. We recommend investigating the possibility of small intestinal metastases in cases of intestinal bleeding or anemia in patients with a history of malignant tumor.

Establishment of a Reflux Esophago-Laryngitis Model in Rats

BackgroundTo investigate the pathophysiology of reflux laryngitis, an experimental model is required.AimThe aim of this study is to establish an animal model of reflux esophago-laryngitis, modifying our previously reported model of chronic acid reflux esophagitis.MethodsThe modified chronic acid reflux esophagitis (m-RE) group (nxa0=xa010), in which the duodenum was wrapped with 2.5xa0mm of Nelaton catheter, was not treated with any drugs. Also postoperatively, two treatment groups (nxa0=xa010 in each) received different dosages of rabeprazole (RPZ): 1.0xa0mg/kg/day (RPZxa01.0 group) or 10.0xa0mg/kg/day (RPZxa010.0 group). As a control group (nxa0=xa05), other rats underwent sham operation. The esophagus and larynx were resected on dayxa014 after the operation, and ulcer score of the esophagus was assessed. The epithelial thickness and leukocyte infiltration of the supraglottic and subglottic laryngeal mucosae were investigated. The number of interleukin (IL)-1β-positive cells was also counted and defined as the IL-1β labeling index.ResultsIn the m-RE group, the epithelial thickness, leukocyte infiltration, and IL-1β labeling index of the supraglottic and subglottic laryngeal mucosae were increased compared with controls (Pxa0<xa00.01). In the RPZ groups, not only the ulcer score of esophagus but also the epithelial thickness, leukocyte infiltration, and IL-1β labeling index of both the supraglottic and subglottic laryngeal mucosae were decreased dose-dependently relative to the m-RE group (Pxa0<xa00.05).ConclusionsOur modified chronic acid reflux esophagitis model proved useful in establishing a rat reflux esophago-laryngitis model, with both pathological laryngeal findings and reflux esophagitis shown to be improved by administration of a proton pump inhibitor.

“Loops-attached rubber band” facilitation of endoscopic submucosal dissection of superficial colorectal neoplasm

of early gastric cancer has improved the success rate of en bloc resection, but it is not widely used to treat the colorectum because of its technical difficulty. It is possible that traction of the lesion may facilitate correct visualization of the le− sion and make it easier to dissect. Several techniques involving traction of lesions have been reported [1± 4], but these methods have not been widely employed because they are difficult to use. Further− more, most devices lift only one part of a lesion, which does not provide a good overview of the area to dissect. Therefore, we designed a multiple traction device, which we have named “Loops−attached rubber band (LARB)”. LARB is able to lift the whole lesion by pulling at multiple points, thereby facilitating correct and better visualization of the lesion than other devices. LARB consists of a circular rubber band connected to many nylon loops (l Fig. 1). After partial dissection of the submucosa of the tumor, the LARB is con− nected to the edge of the exfoliated mu− cosa and the colonic wall opposite the le− sion. This pulls up the whole lesion and opens the resection margin precisely (l Fig. 2 a, b). After the dissection, the ny− lon loop is cut using the loop cutter and the lesion is removed (l Fig. 2 c). ESD using the LARB has been performed on a superficial colorectal lesion at the as− cending colon (l Fig. 3). En bloc resec− tion was achieved without complication. The size of the resected lesion was 28 x94 27 mm, and the procedure time was 50 minutes. We confirm that attaching the LARB to the lesion was not very diffi− cult, and that the device facilitated both correct visualization and easier dissec− tion of the tumor. This preliminary result suggests that LARB−assisted ESD is effective, easily per− formed, and safe for the complete remov− al of large superficial colorectal neo− plasms. “Loops−attached rubber band” facilitation of endoscopic submucosal dissection of superficial colorectal neoplasm