Objectives: To investigate the real-world outcomes of a population-based gastric cancer (GC) screening program in Kawasaki City, a major urban area with a growing aging population and relatively high screening participation rates. Methods: Between December 2012 and 2021, a total of 337,842 citizens in Kawasaki City underwent population-based GC screening, leading to the detection of 1087 GC cases. Esophageal cancer (EC) has been recorded since 2016, with 236 cases detected. To evaluate the short- and long-term clinical outcomes of screening-detected GC and EC, we conducted a retrospective study using the electronic medical records of patients treated at our hospital, a high-volume institution for GC and EC treatment in the city. As a control group, we included 34 GC and EC cases diagnosed based on symptoms at our hospital in 2018. Results: Among the 1087 GC cases detected through population-based screening, 102 cases treated at our hospital were included in the analysis. Of them, 91 patients (89%) were diagnosed with early-stage GC. All screening-detected GC cases underwent either surgery (27 cases) or endoscopic submucosal dissection (75 cases). The five-year survival rates for GC were 90% in males and 86% in females. Eighteen EC cases were also included in the study. The five-year survival rate for screening-detected advanced GC was 70.0%, while for screening-detected EC, it was 100%. Both survival rates were significantly higher than those for symptom-diagnosed GC (30.0%) and EC (40.8%). Conclusions: The prognosis of GC and EC detected through population-based endoscopic screening is significantly better than that of cancers diagnosed based on symptoms. This underscores the effectiveness of endoscopic screening as a valuable tool for the early detection of upper gastrointestinal tract cancers.

BACKGROUND AND AIM:Vedolizumab (VDZ) is often used in older patients with ulcerative colitis (UC) in clinical practice; however, real-world evidence is still limited, including in those with late-onset UC. METHODS:This post hoc analysis of a multicenter, retrospective, observational chart review, enrolling 370 patients with UC receiving VDZ between December 2018 and February 2020, compared effectiveness and safety of VDZ among patients ≥ 70 (n = 40) versus < 70 years (n = 330), and among patients ≥ 70 years with and without late-onset UC (age at disease onset: ≥ 70 [n = 13] versus < 70 years [n = 26]). RESULTS:There were no differences between patients ≥ 70 and < 70 years in clinical remission rates (week 6: 57.5% vs. 47.6%, p = 0.9174; week 14: 62.5% vs. 54.8%, p = 0.1317; week 54: 47.5% vs. 46.4%, p = 0.8149), primary nonresponse (10.0% vs. 15.5%, p = 0.6248), loss of response (12.5% vs. 9.4%, p = 0.5675), or overall safety. Among patients ≥ 70 years, the incidence of adverse drug reactions was numerically greater in those with concomitant corticosteroids than in those without. For older patients with and without late-onset UC, week 54 remission rates were 23.1% versus 57.7% (p = 0.0544); surgery was reported in 3/13 versus 2/26 patients and hospitalization in 5/13 versus 6/26 patients. One death was reported in patients with late-onset UC. CONCLUSIONS:VDZ effectiveness and safety were similar in patients ≥ 70 and < 70 years; VDZ may be a suitable treatment option for patients ≥ 70 years with UC. Patients with late-onset UC tended to have more frequent surgery/hospitalization and lower effectiveness than those without, possibly necessitating greater caution when using VDZ. TRIAL REGISTRATION:Japanese Registry of Clinical Trials registration number: jRCT-1080225363.

BACKGROUND/AIMS:The objectives of this real-world study were to determine 1-year persistence with vedolizumab in patients with ulcerative colitis and to evaluate factors contributing to loss of response. METHODS:In this multicenter, retrospective, observational chart review, patients with moderately to severely active ulcerative colitis who received ≥ 1 dose of vedolizumab in clinical practice at 16 tertiary hospitals in Japan (from December 2018 through February 2020) were enrolled. RESULTS:Persistence with vedolizumab was 64.5% (n = 370); the median follow-up time was 53.2 weeks. Discontinuation due to loss of response among initial clinical remitters was reported in 12.5% (35/281) of patients. Multivariate analysis showed that concomitant use of tacrolimus (odds ratio [OR], 2.76; 95% confidence interval [CI], 1.00-7.62; P= 0.050) and shorter disease duration (OR for median duration ≥ 7.8 years vs. < 7.8 years, 0.33; 95% CI, 0.13-0.82; P= 0.017) were associated with discontinuation due to loss of response. Loss of response was not associated with prior use of anti-tumor necrosis factor alpha therapy, age at the time of treatment, disease severity, or concomitant corticosteroids or immunomodulators. Of the 25 patients with disease duration < 1 year, 32.0% discontinued due to loss of response. CONCLUSIONS:Persistence with vedolizumab was consistent with previous reports. Use of tacrolimus and shorter disease duration were the main predictors of decreased persistence.

BACKGROUND/AIMS:Vedolizumab (VDZ), a gut-selective monoclonal antibody for ulcerative colitis (UC) treatment, has no established biomarkers or clinical features that predict long-term remission. Week 2 remission, a potential predictor of long-term remission, could inform maintenance treatment strategy. METHODS:This retrospective, observational chart review included patients with UC in Japan who initiated VDZ between December 2018 and February 2020. Outcome measures included 14- and 54-week remission rates in patients with week 2 and non-week 2 remission (remission by week 14), 54-week remission rates in patients with week 14 remission and primary nonresponse, and predictive factors of week 2 and week 54 remission (logistic regression). RESULTS:Overall, 332 patients with UC (176 biologic-naïve and 156 biologic-non-naïve) were included. Significantly more biologic-naïve than biologic-non-naïve patients achieved week 2 remission (36.9% vs. 28.2%; odds ratio [OR], 1.43; 95% confidence interval [CI], 1.05-1.94; P= 0.0224). Week 54 remission rates were significantly different between week 14 remission and primary nonresponse (both groups: P< 0.0001), and between week 2 and non-week 2 remission (all patients: OR, 2.41; 95% CI, 1.30-4.48; P= 0.0052; biologic-naïve patients: OR, 2.40; 95% CI, 1.10-5.24; P= 0.0280). Week 2 remission predictors were male sex, no anti-tumor necrosis factor alpha exposure, and normal/mild endoscopic findings. Week 54 remission was significantly associated with week 2 remission and no tacrolimus use. CONCLUSIONS:Week 2 remission with VDZ is a predictor of week 54 remission in patients with UC. Week 2 may be used as an evaluation point for UC treatment decisions. (Japanese Registry of Clinical Trials: jRCT-1080225363).

BACKGROUND/AIMS:Previous literature suggests that the response of patients with ulcerative colitis to vedolizumab may be affected by previous biologic therapy exposure. This real-world study evaluated vedolizumab treatment effectiveness in biologicnon-naïve patients. METHODS:This was a multicenter, retrospective, observational chart review of records from 16 hospitals in Japan (December 1, 2018, to February 29, 2020). Included patients who had ulcerative colitis, were aged ≥ 20 years, and received at least 1 dose of vedolizumab. Outcomes included clinical remission rates from weeks 2 to 54 according to prior biologic exposure status and factors associated with clinical remission up to week 54. RESULTS:A total of 370 eligible patients were included. Clinical remission rates were significantly higher in biologic-naïve (n=197) than in biologic-non-naïve (n=173) patients for weeks 2 to 54 of vedolizumab treatment. Higher clinical remission rates up to week 54 were significantly associated with lower disease severity (partial Mayo score ≤ 4, P= 0.001; albumin ≥ 3.0, P= 0.019) and the duration of prior anti-tumor necrosis factor α (anti-TNFα) therapy (P= 0.026). Patients with anti-TNFα therapy durations of < 3 months, 3 to < 12 months, and ≥ 12 months had clinical remission rates of 28.1%, 32.7%, and 60.0%, respectively (P= 0.001 across groups). CONCLUSIONS:The effectiveness of vedolizumab in biologic-non-naïve patients was significantly influenced by duration of prior anti-TNFα therapy. (Japanese Registry of Clinical Trials: jRCT-1080225363).

5-Aminosalicylate (5-ASA) intolerance complicates ulcerative colitis (UC) management, often necessitating alternative treatment approaches. Granulocyte and monocyte adsorptive apheresis (GMA) has been recognized as a safe treatment option for patients with UC who are refractory or intolerant to conventional drugs, including steroids; however, its effectiveness and safety in patients with 5-ASA intolerance remain unclear. This study aimed to investigate the effectiveness and safety of GMA in patients with UC and 5-ASA intolerance. We conducted a retrospective observational study to evaluate the effectiveness and safety of GMA in patients with UC and 5-ASA intolerance. Eighty-five patients with UC who underwent GMA were assessed, including 21 with 5-ASA intolerance and 64 with 5-ASA tolerance. This study compared the patient characteristics, treatment outcomes, concomitant drugs, and adverse events between the 2 groups. The remission rate was 28.6% (6/21) in the 5-ASA-intolerant group and 31.3% (20/64) in the 5-ASA-tolerant group, with no significant difference between the groups (P = .967). Both groups showed significant reductions in the dose of oral prednisolone and Lichtiger clinical activity index scores following the GMA. Our study suggests that GMA is equally effective and safe in 5-ASA-intolerant and 5-ASA-tolerant patients, offering an alternative treatment option in this challenging clinical scenario.

Objectives: This study evaluated the endoscopic management and clinical outcomes of patients with colonic diverticular bleeding (CDB) during the coronavirus disease 2019 (COVID-19) pandemic. Methods: A total of 388 hospitalized patients diagnosed with CDB at two hospitals during (April 2020-March 2023) and before (April 2017-March 2020) the pandemic were enrolled in the study. We performed one-to-one propensity score matching (PSM) on the participants. We analyzed endoscopic management and clinical outcomes before and during the pandemic using a total of 264 patients matched in a PSM analysis. Results: A total of 213 (1.3%) and 172 (1.2%) colonoscopies were performed before and during the pandemic, respectively in patients with CDB (P = 0.70). After PSM, the number of early colonoscopies (63.6% vs. 76.5%, P = 0.03) and colonoscopies performed outside regular working hours (23.8% vs. 47.7%, P < 0.01) was significantly lower during the pandemic than before it. A univariate logistic regression analysis revealed that the risks of rebleeding within 30 days (odds ratio [OR]: 0.81, P = 0.42) and composite outcome (OR: 0.90, P = 0.69) were not increased during the pandemic. Conclusions: During the pandemic, the number of early colonoscopies and colonoscopies performed outside regular working hours decreased; however, this decrease did not influence rebleeding and composite outcome in patients with CDB.

Abstract Objectives To investigate endoscopic management and clinical outcomes in patients with non‐variceal upper gastrointestinal (GI) bleeding during the coronavirus disease 2019 pandemic. Methods We retrospectively analyzed the data of 332 patients with non‐variceal upper GI bleeding who underwent emergency upper GI endoscopy at three hospitals during the pandemic (April 2020–June 2021) and before the pandemic (January 2019–March 2020). The number of emergency upper GI endoscopies, time from hospital arrival to endoscopy, mortality within 30 days, rebleeding within 30 days, interventional radiology (IVR)/surgery requirement, composite outcome, rates of endoscopic hemostasis procedures, and second‐look endoscopy were investigated using logistic regression. Results Overall, 152 and 180 patients underwent emergency upper GI endoscopies during and before the pandemic, respectively. The mean time from arrival to endoscopy was longer during the pandemic than before it (11.7 vs. 6.1 h, p < 0.01). Multivariate analysis revealed that mortality within 30 days (odds ratio [OR]: 2.27, p = 0.26), rebleeding within 30 days (OR: 0.43, p = 0.17), IVR/surgery requirement (OR: 1.79, p = 0.33), and composite outcome (OR: 0.98, p = 0.96) did not differ significantly between the periods; conversely, endoscopic hemostasis procedures (OR: 0.38, p < 0.01) and second‐look endoscopies (OR: 0.04, p < 0.01) were less likely to be performed during the pandemic than before it. Conclusions Although the time from arrival to endoscopy was significantly longer during the pandemic, it did not affect mortality and rebleeding.

Introduction: Sedative-analgesic agents are reported to reduce the pain and discomfort of esophagogastroduodenoscopy (EGD), but the specific effects of these agents on examination of the esophagogastric junction (EGJ) are unknown. We conducted a prospective, randomized, double-blind clinical trial in which we compared the effects of midazolam and pethidine hydrochloride on EGJ examination during EGD. Methods: The 32 patients included in the study were chosen from among 80 patients scheduled to undergo EGD at our hospital between February 2016 and May 2018. Patients were randomly allocated to intravenous administration of midazolam (n=16) or pethidine (n=16). The midazolam was administered to patients at the same dose as during the previous examination, whereas the pethidine was administered at a dose of 35 mg. Perfect observation was defined as examination of the full circumferential extent of the EGJ. The primary study endpoint was the percentage of patients in whom perfect observation was achieved. Results: Perfect observation was achieved in six patients (37.5%) in the midazolam group and nine patients (56.3%) in the pethidine group (between-group difference: 18.8%, 95% confidence interval [CI]: -59.0% to 21.5%; P=0.29). The mean extent of EGJ examination was 65.0±38.3% in the midazolam group and 78.6±27.3% in the pethidine group (intergroup difference: -13.6%, 95% CI: -37.8% to 10.3%; P=0.25). The mean visual analog scale score for pain and discomfort during endoscopy was 0.75±2.02 in the midazolam group and 2.25±1.77 in the pethidine group, indicating significantly higher levels of discomfort in the pethidine group (intergroup difference: -1.50, 95% CI: -2.87 to -1.30; P=0.033). There was no between-group difference in the number of procedural accidents or degree of the endoscopists' satisfaction. Conclusion: Midazolam was superior to pethidine in relieving discomfort during EGD, but pethidine tended to be better than midazolam for observing the EGJ.

Submucosal endoscopy (third-space endoscopy) can be defined as an endoscopic procedure performed in the submucosal space. This procedure is novel and has been utilized for delivery to the submucosal space in a variety of gastrointestinal diseases, such as a tumor, achalasia, gastroparesis, and subepithelial tumors. The main submucosal endoscopy includes peroral endoscopic myotomy, gastric peroral endoscopic myotomy, Zenker peroral endoscopic myotomy, submucosal tunneling for endoscopic resection, and endoscopic submucosal tunnel dissection. Submucosal endoscopy has been used as a viable alternative to surgical techniques because it is minimally invasive in the treatment and diagnosis of gastrointestinal diseases and disorders. However, there is limited evidence to prove this. This article reviews the current applications and evidence regarding submucosal endoscopy while exploring the possible future clinical applications in this field. As our understanding of these procedures improves, the future of submucosal endoscopy could be promising in the fields of diagnostic and therapeutic endoscopy.

Background: We developed the "Thin silicone loop band (TSLB) ", an endoscopic submucosal dissection (ESD) traction device made of thin elastic silicone molded into a 10-mm-diameter ring. The TSLB can be attached to an EZ clip and passed through the working channel of an endoscope. Aim: To examine the efficacy of TSLB. Methods: Two endoscopists performed ESD with a needle knife for a 20-mm-diameter virtual lesion with an ESD training model. Twelve lesions treated by conventional ESD (group C, n=6) and ESD with TSLB (group T, n=6) were evaluated for submucosal dissection speed. Results: Mean submucosal dissection speed was 50.1±23.3 mm2/min in group C and 82.2±43.1 mm2/min in group T. TSLB traction was successful in all lesions. Discussion: TSLB may be a simple and useful ESD traction device that improves submucosal dissection speed.

The patient was a 32-year-old woman who had a 20-year history of intestinal Behçet's disease without ocular involvement. At the age of 12, she developed oral aphthosis, genital ulcers, erythema nodosum on the lower limbs, and soon developed lower abdominal pain. Colonoscopic examination revealed a round punched-out ulceration in the ileocecal region. Human leukocyte antigen (HLA)-B51 (B5) antigen was negative. Drug therapies with salazosufapyridine and prednisolone was started. When prednisolone was reduced to 15 mg/d, the ileocecal lesion recurred and in addition, diabetes mellitus developed. The patient had been suffered corticosteroid dependence with severe side effects. Since the induction of thalidomide at the age of 14, partial remission that allowed for outpatient visits was maintained for more than 10 years, but negative C-reactive protein (CRP) and endoscopically mucosal healing of the ileocecal ulcer on colonoscopy were not achieved.

Objectives To verify the efficacy and safety of red dichromatic imaging (RDI) in hemostatic procedures during endoscopic submucosal dissection (ESD). Methods This is a multicenter randomized controlled trial of 404 patients who underwent ESD of the esophagus, stomach, colorectum. Patients who received hemostatic treatments by RDI during ESD were defined as the RDI group (n = 204), and those who received hemostatic treatments by white light imaging (WLI) were defined as the WLI group (n = 200). The primary endpoint was a shortening of the hemostasis time. The secondary endpoints were a reduction of the psychological stress experienced by the endoscopist during the hemostatic treatment, a shortened treatment time, and a non-inferior perforation rate, in RDI versus WLI. Results The mean hemostasis time in RDI (n = 860) was not significantly shorter than that in WLI (n = 1049) (62.3 +/- 108.1 vs. 56.2 +/- 74.6 s; P = 0.921). The median hemostasis time was significantly longer in RDI than in WLI (36.0 [18.0-71.0] vs. 28.0 [14.0-66.0] s; P = 0.001) in a sensitivity analysis. The psychological stress was significantly lower in RDI than in WLI (1.71 +/- 0.935 vs. 2.03 +/- 1.038; P < 0.001). There was no significant difference in the ESD treatment time between RDI (n = 161) and WLI (n = 168) (58.0 [35.0-86.0] vs. 60.0 [38.0-88.5] min; P = 0.855). Four perforations were observed, but none of them took place during the hemostatic treatment. Conclusions Hemostatic treatment using RDI does not shorten the hemostasis time. RDI, however, is safe to use for hemostatic procedures and reduces the psychological stress experienced by endoscopists when they perform hemostatic treatment during ESD. UMIN000025134.

AbstractBackground and AimThe aim of this study was to identify the factors associated with liver‐related and non‐liver‐related mortality of patients with hepatitis C virus (HCV) after sustained virologic response (SVR) to direct‐acting antiviral agents (DAAs).MethodsWe conducted a retrospective, single‐center cohort study of HCV patients cured by DAAs.ResultsA total of 330 patients with SVR to DAAs were eligible. The median follow‐up period was 3.38 years (inter‐quartile range: 2.03–4.58). The cumulative liver‐related or non‐liver‐related mortality rates at 1, 3, and 5 years were 0.00 or 1.29%, 2.87 or 3.60%, and 5.10 or 9.46, respectively. Among the liver‐related deaths, 9 of the 10 were from liver cancer. Among the non‐liver‐related deaths, the most common cause was malignancy. Through multivariate analysis using the Cox proportional hazard model, diabetes mellitus (DM, hazard ratio 13.1, 95% confidence interval 2.81–61.3) and a history of hepatocellular carcinoma (HCC, 12.8, 2.76–59.2), independently predicted liver‐related death. No variables were associated with non‐liver‐related death.ConclusionOur findings suggest that DM and a history of HCC are risk factors for liver‐related mortality of HCV patients cured by DAAs. These results indicate that early management of HCV and HCC surveillance of diabetic patients after SVR are important to increase the chance of survival. Further studies are needed to confirm the association of DM and HCC history with survival.

Abstract Background and Aim Colonic diverticular bleeding (CDB) stops spontaneously, but sometimes, excessive bleeding does not allow hemostasis and requires interventional radiology (IR)/surgery. We examined risk factors in patients who required IR/surgery for CDB and late recurrent bleeding rate after IR/surgery. Methods This retrospective case–control study was conducted at a tertiary center. We included 608 patients who required hospitalization for CDB. Patients were investigated for risk factors using logistic regression analysis. We also investigated early and late recurrent bleeding rates following IR/surgery. Results In 261 patients (42.9%), the bleeding source was identified, and endoscopic hemostasis was performed; 23 (3.8%) required IR/surgery. In multivariate analysis, shock state with a blood pressure of ≤90 mmHg (P < 0.001; odds ratio [OR], 20.1; 95% confidence interval [CI], 5.08–79.5), positive extravasation on contrast‐enhanced computed tomography (P < 0.001; OR 9.5, 95% CI 2.85–31.4), two or more early recurrent bleeding episodes (P = 0.002; OR 7.4, 95% CI 2.14–25.4), and right colon as the source of bleeding (P = 0.023; OR 4.1, 95% CI 1.25–14.0) were independent risk factors requiring IR/surgery. Early recurrent bleeding was observed in 0% and 28.0% patients (P < 0.001) in the IR/surgery and no IR/surgery groups, respectively, whereas late recurrent bleeding rate was observed in 43.4% and 30.7% patients (P = 0.203) in the IR/surgery and no IR/surgery groups, respectively. Four patients who required surgery experienced late recurrent bleeding at a site different from the initial CDB. Conclusions Although IR/surgery is an effective hemostatic treatment wherein endoscopic treatment is unsuccessful, late recurrent bleeding cannot be prevented.

Objectives: This study aimed to examine the clinical characteristics of colonic diverticular bleeding (CDB) in elderly individuals. Methods: This retrospective case-control study was conducted at a single tertiary center. A total of 519 patients (356 men and 163 women; mean age of 73.1 ± 12.5 years) with CDB and hospitalized between January 2004 and May 2019 were analyzed. The subjects were divided into two groups: the elderly (274 individuals aged ≥75 years; mean age, 82.1 ± 5.3 years) and non-elderly (245 individuals aged <75 years; mean age, 63.0 ± 10.3 years) groups. Primary outcomes were early and late rebleeding rates, and secondary outcomes were the risk factors for late rebleeding in elderly individuals. Rebleeding occurring within 30 days of hospitalization was defined as early rebleeding, whereas rebleeding occurring after 31 days was defined as late rebleeding. Results: The early rebleeding rates were 30.6% and 33.1% (p = 0.557) in the elderly and non-elderly groups, respectively. The late rebleeding rates were 42.3% and 30.6% (p = 0.005) in the elderly and non-elderly groups, respectively. The 3-year recurrence-free survival was 63.6% in the elderly group and 75.6% in the non-elderly group (log-rank test: p < 0.001). Multivariate analysis revealed the use of non-steroidal anti-inflammatory drugs (NSAIDs) [odds ratio (OR), 3.55], chronic kidney disease (OR, 2.89), and presence of bilateral diverticula (OR, 1.83) as the independent risk factors for late rebleeding in elderly individuals. Conclusions: Elderly individuals with CDB require careful follow-up even after discharge. Furthermore, it is important to consider discontinuing NSAIDs to prevent rebleeding.

OBJECTIVES:The colonoscopic identification of stigmata of recent hemorrhage (SRH) in patients with colonic diverticular bleeding (CDB) is difficult. Factors that influence the identification of SRH in the diagnosis of CDB were investigated.METHODS:This was a retrospective study of 487 early colonoscopy patients with acute lower gastrointestinal bleeding who were diagnosed with CDB. Comorbidities, medications, bowel preparation, use of a transparent cap, use of a water-jet scope, colonoscopy by an expert colonoscopist, and use of a nontraumatic (NT) tube were assessed. A multivariate analysis was used to estimate the odds ratio and 95% confidence interval.RESULTS:Of the 487 colonoscopy patients diagnosed with CDB, 191 (39%) were definitively identified with SRH. The use of a transparent cap, a water-jet scope, an expert colonoscopist, and an NT tube were independent predictive factors for SRH on univariate analysis. A multivariable logistic regression model showed that colonoscopy by an expert colonoscopist and the use of an NT tube were predictive factors for SRH.CONCLUSIONS:Intradiverticular water injection with an NT tube by an expert colonoscopist is useful in identifying CDB, and may help achieve effective endoscopic hemostasis.

[Case 1] A 30-year-old male presented to our hospital with fever. Blood lab results were as follows: T.Bil, 4.8 mg/dL; AST, 3,130 IU/L; ALT, 4,787 IU/L; IgM HAV antibody, positive; and IgA HEV antibody, positive. Superinfection was suspected; however, he was negative for HEV RNA. [Case 2] A 37-year-old female presented to our hospital with fever. Blood lab results were as follows: T.Bil, 10.9 mg/dL; AST, 168 IU/L; ALT, 315 IU/L; EB VCA-IgM, 20; EB VCA-IgG, 160; EBNA, ＜ 10; and IgA HEV antibody, positive. The paired serum test results were as follows: EB VCA-IgM, 80; EB VCA-IgG, 320; and EBNA, ＜ 10. Superinfection was suspected; however, she was negative for HEV RNA. Even for patients who are positive for the IgA HEV antibody, the HEV RNA test should be performed, con-sidering the possibility of a false-positive result arising from other factors for liver dysfunction.

光線力学療法（PDT：photodynamic therapy）は化学放射線療法または放射線療法後の局所遺残再発食道癌に対する救済治療として有用であるが，PDT後の狭窄は線維化が高度で頻回の拡張術を要する．PDTでは選択的なレーザ光照射を行うため先端フードを用いるが，一般的な透明フードではレーザ光がフードを透過することで必要以上の範囲に潰瘍を形成し狭窄を生じる場合がある．遮光可能な既販の黒フードは透明フードと比較して柔らかくレーザ光照射時に内視鏡を固定し難い．今回，我々は黒色油性マジックを塗布したディスポーザブル先端アタッチメント（以下，黒塗フード）を用いたPDT後狭窄予防の工夫を考案した．当院における7例の黒塗フードを用いた食道PDTでは，局所完全奏功率は85.7%で，食道狭窄は認められなかった．黒塗フードはレーザ光の乱反射を防ぎつつ，より確実で限局的なレーザ光照射に有用であったため，手技の実際について紹介する．

Abstract Endoscopic procedures increase the risk of transmission of severe acute respiratory syndrome coronavirus 2 to medical staff, because aerosols are generated during upper gastrointestinal endoscopy. There have been several reported studies on devices for infection prevention; however, few reports have validated them. Therefore, we developed a novel mask to prevent the diffusion of aerosol droplets from patients undergoing endoscopy. We compared microdroplet dispersion during coughing episodes when using the novel mask with microdroplet dispersion when using the conventional mouthpiece alone. The mean number of microdroplets was significantly smaller in the group that used the novel mask (57.9 ± 122.91 vs 933.6 ± 119.80 droplets; P = .01). The novel mask may aid in reducing the degree of exposure of medical personnel to microdroplets and the risk of subsequent infection.