Nobuya Kobayashi

Flexible magnifying endoscopy with narrow band imaging for the diagnosis of uterine cervical tumors: A cooperative study among gastrointestinal endoscopists and gynecologists to explore a novel microvascular classification system

Narrow band imaging with magnifying endoscopy (NBI-ME), which is useful for the assessment of micro-vessels, has excellent diagnostic potential for early gastrointestinal epithelial neoplasia. Conventional diagnostic tools for uterine cervical epithelial tumors are still unsatisfactory. An accurate diagnostic tool for uterine cervical epithelial tumors is required to preserve the reproductive ability of young women with uterine cervical tumors. Flexible NBI-ME was performed in patients with cervical squamous cell lesions that required further examinations based on their Pap smear results (cytology ≥ low-grade squamous intraepithelial lesion) at Kagawa University Hospital between April 2014 and April 2015. NBI-ME results concordant with the punch biopsy sites were compared with the histological results. A retrospective review of the NBI-ME images identified abnormal NBI-ME results regarding micro-vascular patterns. All images were categorized as having abnormal features. NBI-ME revealed the following vascular pattern differences of different stage tumors: Dot-like vessels without irregular arrangements and high density in cervical intraepithelial neoplasia (CIN) CIN1-CIN2; dot-like vessels with irregular arrangements and high density in CIN3-carcinoma in situ; crawling vessels in minimum invasive cancer; and willow branch vessels and new tumor vessels in invasive cancer. NBI-ME may be an effective diagnostic tool for uterine cervical epithelial tumors, which may lead to the establishment of a novel classification system.

Comparison of submucosal tunneling biopsy versus EUS-guided FNA for gastric subepithelial lesions: a prospective study with crossover design

Background and study aims  Endoscopic ultrasound-guided fine needle aspiration (FNA) for gastrointestinal subepithelial lesions (SELs) has limited diagnostic accuracy due to technical problems and small lesion size. We previously reported a novel submucosal tunneling biopsy (STB) technique for sampling SELs. This study aimed to evaluate the diagnostic ability and safety of STB compared to that of FNA for SELs. Patients and methods  The study was a non-randomized, prospective comparative study with crossover design in patients with endoluminal gastric SELs. Forty-three patients, including 29 cases with lesions < 2 cm were enrolled. A crossover design with 2 intervention stages (Group A: FNA followed by STB for 23 SELs, Group B: STB followed by FNA for 20 SELs) was implemented. The primary outcome was the diagnostic yield (DY). Secondary outcomes were technical success rate, procedure time, complication rate, and sample quality. Results  The DY of STB was significantly higher than that of FNA (100 % vs. 34.8 %; P  < 0.0001) in group A, including 100 % in overall STB. The technical success rate of STB was significantly higher than that of FNA (100 % vs. 56.5 %; P  = 0.0006), whereas the median procedure time of STB was significantly longer than that of FNA (37 minutes vs. 18 minutes; P  < 0.0001). The median specimen area of STB samples was markedly larger than that of FNA samples (5.54 mm 2 vs. 0.69 mm 2 ; P  < 0.001). No complications occurred in either method. Conclusions  STB had significantly superior diagnostic ability and a more adequate sample quality than FNA for endoluminal gastric SELs, indicating the suitability of STB for small SELs. Clinical trial registration: UMIN 000006754

Innovative pure non-exposed endoscopic full-thickness resection using an endoscopic suturing device

re 1. A, The double-armed bar suturing system (DBSS; Zeon Medical Co., Tokyo, Japan). B, A 30-mm virtual tumor was created with the technique. C, One stitch was made at the center of the ring-shaped trench by using the DBSS. D, Five full-thickness stitches with a 3-mm pitch. ll-thickness resection using an IT knife 2 and an SB knife. F, Once the full-thickness resection was completed, the tumor was retrieved with net ps (Roth net, BX00711050, US Endoscopy).

Novel approach of laparoscopic and endoscopic cooperative surgery (LECS) for cholecystectomy

Abstract Background: Endoscopic submucosal dissection (ESD) techniques, such as generating an artificial space between digestive tract layers for safer dissection, were thought to be safer for the resection of organs in cholecystectomy. We investigated whether combinations of endoscopic techniques and laparoscopic techniques could be performed more safely and rapidly. Material and methods: Laparoscopic and endoscopic cooperative-cholecystectomy (LEC-chole) and conventional laparoscopic cholecystectomy (Lapa-chole) were performed in six dogs. Operation time was defined as the time from the creation of the first port to the retrieval of the resected gallbladder (GB); and GB bed dissection time was the time from local injection of natural saline to the clipping of the cystic duct. The main roles of the endoscope in LEC-chole were to obtain a sufficient cutting space via local injection of natural saline to the GB bed and to monitor the operative view without laparoscopic camera, thus omitting the umbilical port. Results: The operation times were 60 ± 18.3 minutes for LEC-chole and 95 ± 7.0 for Lapa-chole (p = .036). The GB bed dissection times were 31 ± 8.54 minutes in LEC-chole and 50.6 ± 7.37 minutes in Lapa-chole (p = 0.048). There were significant differences in liver damage and bleeding (p = 0.116), but there were no significant differences in one-month survival. Conclusions: The application of LEC-chole may be expanded to cholecystectomy.

Oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor

Gastric submucosal tumors (SMTs) less than 2 cm are generally considered benign neoplasms, and endoscopic observation is recommended, but SMTs over 2 cm, 40% of which are gastrointestinal stromal tumors (GISTs), have malignant potential. Although the Japanese Guidelines for GIST recommend partial surgical resection for GIST over 2 cm with malignant potential as well as en bloc large tissue sample to obtain appropriate and large specimens of SMTs, several reports have been published on tissue sampling of SMTs, such as with endoscopic ultrasound sound fine needle aspiration, submucosal tunneling bloc biopsy, and the combination of bite biopsy and endoscopic mucosal resection. Because a simpler, more accurate method is needed for appropriate treatment, we developed oval mucosal opening bloc biopsy after incision and widening by ring thread traction for submucosal tumor (OMOB) approach. OMOB was simple and enabled us to obtain large samples under direct procedure view as well as allowed us to restore to original mucosa.

Funnel-shaped retrieval device for wrapping large colorectal resection specimens

Endoscopic submucosal dissection (ESD) has facilitated en bloc resection of large colorectal tumors [1]. The retrieval of a moderately sized specimen after ESD is common with use of a net forceps [2]. It is difficult however to retrieve a large colorectal specimen without any damage because of the typical anatomy of the anal canal with its narrow lumen, which sometimes results in the failure of accurate pathological evaluation. Although several retrieval methods have been reported recently, they seem to be insufficient in terms of wrapping the whole of a large specimen [3, 4]. Here we introduce a novel procedure that is reliable for the retrieval of a large colorectal specimen. A 51-year-old man presented with a 40-mm laterally spreading tumor located in the cecum. The retrieval method using a net forceps via the anal canal might have damaged the en bloc specimen after complete ESD. Therefore, we developed a new retrieval method using an overtube (Top Corporation, Tokyo, Japan) and a piece of waterproof cloth from an operating gown (Hopes isolation gown JIG-01B: Japan Medical Products, Hokkaido, Japan). After informed consent had been obtained from the patient, the following strategy was designed. First, the en bloc ESD specimen was carried from the cecum to the lower rectum using grasping forceps. Next, a fanshaped waterproof cloth was hand-made and this was attached to an overtube in a funnel-shaped manner (▶Fig. 1). After inserting the overtube into the lower rectum, the large specimen was wrapped in the cloth using the grasping forceps that had been inserted through the endoscope channel (▶Fig. 2). Finally, the endoscope and the overtube were taken out together from the anal canal (▶Fig. 3; ▶Video1). The resected specimen (50×45mm in diameter) was completely retrieved without any damage or complications (▶Fig. 4). This innovative method using a particular cloth, which has several functions including water repellency and shape memory, may be suitable for the retrieval of large colorectal specimens.

Surgery avoided by the use of over-the-scope clips for severe duodenal complications associated with endoscopic mucosal resection

During endoscopic treatment for duodenal neoplasm, hazardous complications such as perforation and bleeding sometimes occur owing to the anatomical characteristics of the duodenum [1–3]. Although surgical repair has been traditionally required for these complications, the procedure is invasive and complicated [4]. A currently available overthe-scope clip (OTSC; Ovesco Endoscopy, Tübingen, Germany) has provided excellent outcomes for gastrointestinal refractory bleeding and full-thickness defects [5]. Here, we describe a notable case in which iatrogenic duodenal complications could be managed with OTSCs. A 56-year-old man presented with a duodenal adenoma that showed a reddish and flat elevated lesion, approximately 10mm in diameter, located in the posterior wall of the second duodenal portion (▶Fig. 1). After submucosal injection, cap-assisted endoscopic mucosal resection (EMR) was performed under carbon dioxide insufflation. A large full-thickness perforation, 20mm in diameter, occurred (▶Fig. 2 a), and spurting arterial bleeding was seen (▶Fig. 2 b). The bleeding was accompanied by hemorrhagic shock and was immediately controlled using hemostatic forceps (Coagrasper; Olympus, Tokyo, Japan). OTSCs were then applied to close the defect at the perforation site, after obtaining informed consent. Grasping forceps (Twingrasper; Ovesco Endoscopy) were used to approximate the edges of the large defect. The defect was mostly closed by one OTSC (t type, 9mm), and the remaining defect was closed by an additional OTSC using simple suction (▶Fig. 3, ▶Video1). A radiographic examination 5 days later confirmed no leakage at the perforation site (▶Fig. 4). The patient was discharged without additional interventions 19 days later. A histological examination revealed E-Videos

One-to-One Correspondence Locations of Resected Polyps after Endoscopic Resection Using Catcher Tagged Method: A Randomized Prospective Study

Background/Aims: Multiple colorectal polyps with a diameter in the range of 10–19 mm are unable to be retrieved through a 3-mm endoscopic channel by the aspiration method. This study aims to assess the usefulness of Catcher Tag retrieval, which not only allows the accurate identification of the resected location but also enables the easiest retrieval in a short time without any special device. Methods: One hundred thirty five patients (483 polyps) were diagnosed with colorectal neoplasm, and 64 patients (225 polyps) were enrolled and randomly allocated into the Net forceps group (NET) and the Catcher Tagged group (TAG). In TAG, 3 types of colored ring-threads were used to retrieve resected polyps. After local injection of natural saline, ring-threads were placed close to polyps. The primary outcome was the number of one-to-one correspondence locations (UMIN000020826). Results: There was significant difference in one-to-one correspondence (p = 0.004). The average retrieval procedure time was 13.56 ± 3.47 (min) in NET and 3.55 ± 1.68 in TAG (p = 0.006). In NET, 1 polyp in each of 4 cases was lost during endoscopic mucosal resection and 2 polyps were lost in 1 case. In TAG, no polyp was lost (p = 0.016). Conclusion: The Catcher Tagged method is very useful for accurate one-to-one correspondence locations and pathological evaluation, and easy-to-retrieve multiple resected specimens.

Novel and safer endoscopic cholecystectomy using only a flexible endoscope via single port

AIM To apply the laparoscopic and endoscopic cooperative surgery concept, we investigated whether endoscopic cholecystectomy could be performed more safely and rapidly via only 1 port or not. METHODS Two dogs (11 and 13-mo-old female Beagle) were used in this study. Only 1 blunt port was created, and a flexible endoscope with a tip attachment was inserted between the fundus of gallbladder and liver. After local injection of saline to the gallbladder bed, resection of the gallbladder bed from the liver was performed. After complete resection of the gallbladder bed, the gallbladder was pulled up to resect its neck using the Ring-shaped thread technique. The neck of the gallbladder was cut using scissor forceps. Resected gallbladder was retrieved using endoscopic net forceps via a port. RESULTS The operation times from general anesthetizing with sevoflurane to finishing the closure of the blunt port site were about 50 min and 60 min respectively. The resection times of gallbladder bed were about 15 min and 13 min respectively without liver injury and bleeding at all. Feed were given just after next day of operation, and they had a good appetite. Two dogs are in good health now and no complications for 1 mo after endoscopic cholecystectomy using only a flexible endoscope via one port. CONCLUSION We are sure of great feasibility of endoscopic cholecystectomy via single port for human.