Gastrojejunal anastomotic (GJA) ulcers are a common complication after Roux-en-Y gastric bypass (RYGB) and may be refractory to medical therapy. Impaired mucosal perfusion is suspected to contribute to non-healing ulcers, but no method exists to directly assess ischemia. We evaluated the feasibility of real-time endoscopic tissue oxygen saturation (StO2) imaging to quantify mucosal perfusion and its association with ulcer healing. In this prospective study, 51 adults were included: 18 with normal gastrointestinal anatomy, 26 with RYGB anatomy without complications, and a subgroup of 7 RYGB patients with confirmed GJA ulcers. StO2 was measured in the esophagus, stomach/pouch, duodenum/jejunum, and anastomotic sites using an endoscopic StO2 imaging system. Ulcer patients received maximal medical therapy and were reassessed by follow-up endoscopy. StO2 values were compared across regions and between healed and non-healed ulcers. In normal anatomy, esophageal StO2 was lower than gastric and duodenal values, while stomach and duodenum were similar. In RYGB patients without complications, StO2 values were comparable across the pouch, anastomosis, and Roux limb. Among ulcers, healed sites had significantly higher StO2 than non-healed sites (p = 0.002). Healed ulcers exhibited StO2 near baseline anastomotic levels, whereas non-healed ulcers demonstrated markedly reduced StO2. Endoscopic StO2 imaging is feasible and enables quantitative assessment of mucosal perfusion in both normal and post-RYGB anatomy. Low StO2 at GJA ulcers is associated with poor healing, highlighting its potential to identify ischemic ulcers that may benefit from early surgical intervention. However, given the small sample size, particularly in the ulcer subgroup, these findings should be considered preliminary and interpreted with caution. Larger studies are needed to validate StO2 thresholds and define its role in clinical decision-making after RYGB.

Background and Aim Amber-red color imaging (ACI) is a new image-enhanced modality designed to improve visualization of blood vessels during gastrointestinal bleeding. Its role in endoscopic submucosal dissection (ESD) has not been evaluated. We aimed to describe ACI’s utility in ESD through a first clinical series. Methods Prospective case series of eight patients undergoing upper or lower gastrointestinal ESD at a tertiary center using a novel processor with ACI capability. Endoscopists alternated between white-light imaging (WLI) and ACI. Outcomes included Likert-type score for visibility across two groups (expert and non-expert), dissection speed, and adverse events. Results Eight ESD cases (1 esophageal, 7 colorectal) were included. En bloc resection was achieved in all cases (100%), with no adverse events. Mean procedure time was 71.8 minutes (range 30–180), mean specimen size 58.8 ± 43.3 mm, and dissection speed 44.7 mm2/min.ACI significantly improved submucosal visibility for both experts (6.27 ± 1.33 vs 9.22 ± 0.94; P < 0.001) and non-experts (7.60 ± 0.83 vs 9.56 ± 0.62; P < 0.001). Similar improvements were observed for blood vessel recognition (experts: 7.38 ± 1.98 vs 8.89 ± 1.13; P < 0.001; non-experts: 8.00 ± 1.04 vs 9.28 ± 0.83; P = 0.002). Non-experts using ACI outperformed experts using WLI (P < 0.001).Muscularis propria visualization improved only among non-experts (P = 0.020). ACI did not improve active bleeding visibility in either group. Conclusions ACI enhances submucosal visualization during ESD and may serve as a useful therapeutic adjunct.

BACKGROUND:Endoscopic submucosal dissection (ESD) is an established therapy for superficial esophageal lesions. Endoscopic ultrasound (EUS) is commonly used to assess submucosal invasion (SMI) and lymphadenopathy. METHOD:Retrospective cohort of patients with esophageal and gastroesophageal junction lesions undergoing EUS before ESD (2014-2025). EUS T stage was compared with final pathology to evaluate detection of SMI. RESULTS:Seventy-five lesions were analyzed (mean age 69 years; 70.7% male). EUS staging identified Tis in 24% (N = 18), T1a in 25.3% (N = 19), T1b in 49.3% (N = 37) and T2 in 1.3% (N = 1). Final ESD pathology revealed adenocarcinoma in 65.3% (N = 49), SCC in 21.3% (N = 16) and high-grade dysplasia in 13.3% (N = 10). By pathology, 41.3% were staged as T1a (N = 31), 40.0% as T1b (N = 30) and 18.7% as Tis (14). EUS correctly determined SMI in 81.3% (N = 61), similarly for adenocarcinoma (80.7%) and squamous cell carcinoma (83.3%). Staging errors occurred in 18.7% of lesions, and equal for understaging and overstaging (each 9.3%, N = 7). CONCLUSION:EUS showed limited reliability for pre-ESD staging of esophageal/GEJ lesions, with suboptimal performance in detecting SMI. As depth of invasion determines therapeutic strategy, EUS should not be used in isolation but rather alongside expert endoscopic assessment and biopsy. ESD remains central by offering definitive treatment and precise histologic staging.

INTRODUCTION:To characterize the smoke generated during several endoscopic procedures and evaluate the efficacy of a smoke evacuation system as a preventative measure. METHODS:Monitoring devices in closure proximity to patients measured particulate matter and volatile organic compounds during endoscopic procedures. The impact of a smoke evacuator system was also assessed. RESULTS:Particulate matter and volatile organic compound levels were significantly elevated during all procedures. The smoke evacuator reduced the exposure. DISCUSSION:Smoke produced during endoscopy is a potential health risk for endoscopy staff. Protective measures and further research on long-term exposure effects are warranted.