Double staining with crystal violet and methylene blue is appropriate for colonic endocytoscopy: an in vivo prospective pilot study.

BACKGROUND AND AIM: Endocytoscopy (EC) at ultra-high magnification enables in vivo visualization of cellular atypia of gastrointestinal mucosae. Clear images are essential for precise diagnosis by EC. The aim of the present study was to evaluate the optimal staining method for EC in the colon. METHODS: Thirty prospectively enrolled patients were allocated 1:1:1 to three distinct staining methods: 0.05% crystal violet (CV) alone, 1% methylene blue (MB) alone, or CV+MB (CM double). Normal rectal mucosae were stained with each dye and videos of EC images were recorded. Visibility of nuclei and gland formation after staining were evaluated as 'recognizable' or 'not recognizable'. Time for each parameter to become 'recognizable' was measured, and the average times for the three staining regimens were compared. RESULTS: MB alone and CM double staining resulted in 'recognizable' (102 ± 27 vs 89 ± 22 s, P=0.263) nuclei within comparable periods of time, whereas CV alone was unable to identify nuclei. Gland formation became 'recognizable' sooner after CM double staining than after MB alone (61 ± 16 vs 108 ± 24 s, P<0.001). CONCLUSIONS: Double staining with CV and MB, which rapidly provided recognizable images of both nuclei and gland formation, is an appropriate staining regimen for colonic EC.

Submucosal Injection Using Epinephrine-Added Saline in Cold Snare Polypectomy for Colorectal Polyps Shortens Time Required for Resection: A Randomized Controlled Study.

AIMS: Immediate bleeding after cold snare polypectomy (CSP) for colorectal polyps might interfere with confirmation of residuals and prolong the time required for resection. We investigated whether submucosal epinephrine-added saline injection reduces the time required for the CSP procedure. METHODS: We conducted a single-center, prospective, randomized controlled trial (clinical trial registration number: UMIN000046770). Patients with colorectal polyps ≤ 10 mm were randomly allocated to either CSP with epinephrine-added submucosal injection (CEMR group) or conventional CSP (CSP group). The primary outcome was the time required for resection defined as the time from the initiation of resection (the first insertion of the snare in the CSP group or the injection needle in the CEMR group) to the end of resection (confirming complete resection endoscopically after recognizing the cessation of immediate bleeding) in each lesion, and the secondary outcome was the time to spontaneous cessation of immediate bleeding after resection defined as the time from ensnaring the lesion to confirming the spontaneous cessation of immediate bleeding. RESULTS: A total of 126 patients were randomly assigned. Finally, 261 lesions in 118 patients (CEMR group, n = 59; CSP group, n = 59) were analyzed. The time required for resection calculated using the least-square mean was significantly shorter in the CEMR group (106.3 s, 95% CI 97.5 to 115.4 s) than in the CSP group (130.9 s, 95% CI 121.2 to 140.7 s) (P < 0.001). The time to spontaneous cessation of immediate bleeding was also significantly shorter in the CEMR group (20.4 s, 95% CI 14.3 to 26.5 s) than in the CSP group (74.2 s, 95% CI 67.6 to 80.7 s) (P < 0.001). Neither group had cases requiring hemostasis, perforation, or delayed bleeding. CONCLUSIONS: CEMR shortened the time for resection by shortening the time to cessation of immediate bleeding compared with conventional CSP in colorectal polyps ≤ 10 mm.

Risk Factors Indicating Difficulty During Gastric Endoscopic Submucosal Dissection for Inexperienced Endoscopists: A Retrospective Study.

AIM: Factors that may make endoscopic submucosal dissection (ESD) difficult for operators have been evaluated according to results based on the performance of experienced endoscopists. This study aimed to verify the predictors of difficult gastric ESD for ESD beginners. METHODS: From January 2015 to December 2021, 466 superficial gastric neoplasms were treated with ESD at Showa University Hospital. Excluding 103 lesions that performed ESD by experts who experienced more than 80 ESDs, a total of 363 lesions were included. The lesions were divided into two groups according to the ESD performance experience of the operator: ESD beginner (EB; ESD experience≤30 cases) and ESD intermediate (EI; ESD experience 31-80 cases) groups. Relationships between difficult ESD (having at least one of the following: procedure time>60 min, incomplete resection, change of operator, and occurrence of severe complications) and clinicopathological findings of the lesion were analyzed. RESULTS: The complete resection rates and the difficult ESD rates in the EB and EI groups were 99.3%, 94.8%, and 61.2%, 50.7%, respectively. In the EB group, univariate analysis showed that difficult ESD rate was significantly higher in the non-lower third lesions, the lesser curvature lesions, and cancerous lesions. In the EI group, univariate analysis showed that difficult ESD rate was significantly higher in lesion with ≥20 mm size, lesser curvature lesions, lesions with ulcers, and submucosal cancers. Multivariate analysis showed that the lesser curvature location and cancerous histology in the EB group and ≥20 mm lesion size, the lesser curvature location and submucosal invasion in the EI group were independent predictors of difficult ESD. CONCLUSIONS: The lesser curvature location is recognized as independent ESD difficulty factor for both beginners and intermediates. Cases with lesions located in the lesser curvature should not be selected for gastric ESD training by beginners.

Small intestinal bleeding and stricture caused by Meckel's diverticulum.

A 44-year-old man presented to our hospital with lower gastrointestinal bleeding. We performed balloon-assisted enteroscopy, which revealed diverticulum and stricture at the ileum. The patient underwent segmental small bowel resection and diagnosed with Meckel's diverticulum. We should keep in mind the possibility of intestinal stricture due to Meckel's diverticulum.

Case of Colorectal Cancer After Cold Snare Polypectomy Successfully Salvaged on Endoscopic Submucosal Dissection.

Cold snare polypectomy is a well-established method for the resection of colorectal polyps measuring less than 10 mm in size. It may be performed in patients with early colorectal cancers because of the difficulty of endoscopic diagnosis. However, the therapeutic effect of cold snare polypectomy on cancers is unknown, and the need for appropriate surveillance and additional treatment for these patients remains to be fulfilled. Endoscopic submucosal dissection has been reported as a safe and effective method for treating recurrent or residual colorectal neoplasia following hot endoscopic mucosal resection. This report is of a case of a colorectal tumor measuring 8 mm that was treated using cold snare polypectomy and resulted in residual cancer. Endoscopic submucosal dissection was selected as salvage treatment for the residual lesion, and histopathological examination revealed free horizontal and vertical margins. We believe that performing endoscopic submucosal dissection at the site of the cancer resected with cold snare polypectomy ensured that there was no residual cancer left. It may be hypothesized that endoscopic submucosal dissection could evolve as the treatment of choice for patients with colorectal cancer after cold snare polypectomy.

Successful Management of Pharyngeal Perforation Caused by Overtube Insertion During Endoscopic Submucosal Dissection.

A woman in her 70s underwent endoscopic submucosal dissection (ESD) for gastric-type adenoma in the anterior wall of the upper gastric body with intravenous anesthesia. We decided to use an overtube to control the air volume in the stomach. The overtube was inserted under endoscopic guidance using a sufficient amount of lubricating jelly. We encountered resistance when the top of the overtube was advanced to the pharynx; therefore, we stopped the overtube insertion and pulled the tube out immediately. We observed a linear injury in the posterior wall of the hypopharynx. The injury was deep and diagnosed as a pharyngeal perforation. Computed tomography (CT) revealed free air in the neck, with mediastinal emphysema. Conservative treatment was initiated after consultation with the otorhinolaryngologist; the patient received nothing per mouth and was administered intravenous antibiotics. The patient did not develop a fever and no signs of inflammation were observed. CT performed on postoperative day (POD) 5 revealed the disappearance of the mediastinal emphysema and a soft diet was introduced. The patient was discharged on POD 7. The ESD was postponed to two months later and was performed successfully. The scar of the perforation site was confirmed. In this report, we describe an extremely rare adverse event associated with overtube insertion. Although the incidence of pharyngeal perforation is low and its management is controversial, it was done without surgical intervention in the present case.

Diagnosis of colorectal lesions with the magnifying narrow-band imaging system.

BACKGROUND: Narrow-band imaging (NBI) emphasizes the surface microvasculature of the GI tract and may help in detecting small neoplasms. OBJECTIVE: The aim of this study was to clarify the value of the NBI system in tissue characterization and differential diagnosis. DESIGN: A prospective study. SETTING: Digestive Disease Center of Showa University Northern Yokohama Hospital. PATIENTS: The subjects were 495 patients who, from January 2006 to June 2007, underwent a complete colonoscopic examination. A total of 617 lesions were evaluated in the 495 patients (33 hyperplastic polyps, 532 adenomas, 52 submucosally invasive [T1] cancers). RESULTS: Most hyperplastic polyps showed a faint pattern. The vascular patterns of adenomas were mainly the network pattern or the dense pattern. The major vascular patterns of cancers were the irregular pattern and the sparse pattern. The irregular pattern was characteristic for protruded or flat-elevated cancers, whereas the sparse pattern was unique for depressed cancers. When we assumed that the faint pattern was diagnostic for hyperplastic polyps, we could differentiate between neoplastic and non-neoplastic lesions with a sensitivity of 90.9% and a specificity of 97.1%. Likewise, irregular and sparse patterns were assumed to be indices of massively invasive submucosal cancer, the sensitivity was 100%, the specificity was 95.8%, and the accuracy rate was 96.1%. LIMITATIONS: This study was performed at a single center. CONCLUSIONS: The NBI system was valuable for distinguishing between neoplastic and non-neoplastic lesions, as well as between cancers and adenomas. Vascular pattern analysis can also be a promising tool for determining treatment selection, either endoscopy or surgery.

Endocytoscopic narrow-band imaging efficiency for evaluation of inflammatory activity in ulcerative colitis.

AIM: To assess the efficacy of endocytoscopic narrow-band imaging (EC-NBI) for evaluating the severity of inflammation in ulcerative colitis (UC). METHODS: This retrospective study was conducted at a single tertiary care referral center. We included UC patients who underwent colonoscopy with endocytoscopy from July 2010 to December 2013. EC-NBI was performed, and the images were evaluated by assessing visibility, increased vascularization, and the increased calibers of capillaries and were classified as Obscure, Visible or Dilated. Obscure was indicative of inactive disease, while Visible and Dilated were indicative of acute inflammation. This study received Institutional Review Board approval. The primary outcome measures included the diagnostic ability of EC-NBI to distinguish between active and inactive UC on the basis of histological activity. The conventional endoscopic images were classified according to the Mayo endoscopic score. A score of 0 or 1 indicated inactive disease, whereas a score of 2 indicated active disease. RESULTS: Fifty-two patients were enrolled. There was a strong correlation between the EC-NBI findings and the histological assessment (r=0.871, P<0.01). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of EC-NBI for diagnosing acute inflammation were 84.0%, 100%, 87.1%, 100%, and 92.3%, respectively, while those for the Mayo endoscopic score were 100%, 40.7%, 100%, 61.0%, and 69.2%, respectively. Compared with conventional endoscopy, EC-NBI was superior in diagnostic specificity, negative predictive value, and accuracy (P<0.001, P=0.001 and P=0.047, respectively). CONCLUSION: The EC-NBI finding of capillaries in the rectal mucosa was strongly correlated with histological inflammation and aided in the differential diagnosis between active and inactive UC.

Magnifying narrow-band imaging of surface patterns for diagnosing colorectal cancer.

Narrow-band imaging (NBI) of surface microvessels of colorectal lesions is useful for differentiating neoplasms from non-neoplasms and for predicting histopathological diagnosis. Furthermore, NBI of surface microstructure, or 'surface pattern', is valuable for predicting histopathology in colorectal cancer. The aim of the present study was to investigate whether surface patterns could be used to predict invasion depth in colorectal cancer, and to compare the accuracy of surface pattern diagnosis in each macroscopic type. Between January 2010 and March 2011, a series of 357 consecutive patients with 378 early colorectal cancers were observed by magnifying NBI and the surface pattern was prospectively evaluated. Surface pattern was classified into 3 types: type I, microstructure was clearly recognised with uniform arrangement and form; type II, microstructure was obscured with heterogeneous arrangement and form; and type III, microstructure was invisible. We also classified the macroscopic type into 3 categories: depressed, protruded and flat elevated. Assuming that type III was an index of massively invasive lesions in the submucosal layer (SMm), the sensitivity, specificity and accuracy were 56.9, 91.7 and 85.7%, respectively. The sensitivity, specificity and accuracy of type III for the diagnosis of SMm in each macroscopic type were: depressed, 88.9, 40.0 and 63.2%, respectively; protruded: 34.8, 96.4 and 90.0%, respectively; and flat elevated, 54.2, 92.7 and 85.0%, respectively. These results suggest that the diagnostic accuracy of surface pattern was insufficient and particularly poor for depressed-type lesions.

A case of autoimmune pancreatitis responding to steroid therapy. Evidence of histologic recovery.

We report a case of autoimmune pancreatitis without obvious evidence of autoimmunological participation, which responded well to steroid treatment and provided histologic and radiographic evidence for this improvement. A 68-year-old woman presented abdominal fullness, diffuse pancreatic swelling on abdominal computed tomography and ultrasonography, and diffuse narrowing of the main pancreatic duct on endoscopic retrograde pancreatography. Transgastric aspiration needle biopsy of the body of the pancreas performed under endoscopic ultrasonography showed severe atrophy of acinar cells, infiltration of T lymphocytes. She was diagnosed as having autoimmune pancreatitis without obvious evidence of autoimmunological participation. Administration of 30 mg/day of predonisolone was started. Computed tomography showed marked improvement of the diffuse swelling of the pancreas, and endoscopic retrograde pancreatograpy showed amelioration of the narrowing of the main pancreatic duct after the start of treatment. Pancreatic tissue obtained by needle biopsy after the start of treatment with predonisolone revealed marked histologic improvement, including amelioration of the fibrosis, and infiltration of inflammatory lymphocytes, and a substantial increase in the number of pancreatic acinar cells. The present report is the first to demonstrate histologic recovery of autoimmune pancreatitis after steroid therapy.