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Law, Ryan J

Mayo Clinic

Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, United States.

Citations 10

Endoscopic Ultrasound-Guided Gastroenterostomy for Gastric Outlet Obstruction: A Comparison of Duodenal Versus Jejunal Placement on Patient Outcomes
Khan, Rishad , Law, Ryan , Guralwar, Chinmay , Bauss, Jacob, Suman, Garima , Han, S, Buttar, Navtej, Song, Louis–Michel Wong Kee, Law, Ryan J, AbiMansour, Jad P. , Vargas, Eric J , Wong Kee Song, Louis-Michel, Storm, Andrew C , Chandrasekhara, Vinay , Bauss, Jacob M. , Han, Samuel, Vargas, Eric J. , Dayyeh, Barham K. Abu , Buttar, Navtej , Storm, Andrew C. , Chandrasekhara, Vinay

Endoscopy International Open | July 11, 2026 | Volume: 14 | Issue: CP | Pages: No page available

10.1055/a-2913-6628 Get It

Abstract Background and Aims EUS-guided gastroenterostomy (EUS-GE) is an effective option to palliate symptoms of gastric outlet obstruction (GOO). While the jejunum is conventionally targeted (EUS-GJ), targeting the duodenum (EUS-GD) may offer clinical advantages. Outcomes were compared for EUS-GJ and EUS-GD. Methods Adult patients who underwent EUS-GE for GOO between 2020 and 2024 were included and categorized as an EUS-GD if the stent entered the transverse or ascending duodenum or an EUS-GJ if the stent entered more distally. The primary outcome was clinical success (soft diet tolerance at 7 days). Secondary outcomes included adverse events (AEs), stent misdeployment, and unplanned endoscopic reintervention. Baseline demographic variables and outcomes were compared with statistical significance at p < 0.05. Results Of the 139 included patients (median age 67 years (IQR 61–74); 41% female), 105 underwent EUS-GJ and 34 underwent EUS-GD. Clinical success was 98% for EUS-GJ and 94% for EUS-GD (p = 0.25). The misdeployment rate was 7% for EUS-GJ and 0% for EUS-GD (p = 0.19). The AE rate was 22% for EUS-GJ and 12% for EUS-GD (p = 0.23). There were no significant differences for stent obstruction (EUS-GJ 12% vs. EUS-GD 6%), bleeding (2% vs. 6%), perforation (4% vs. 0%), stent migration (1% vs. 0%), infection (3% vs. 0%), and unplanned reintervention (14% vs. 9%). Conclusion Both EUS-GJ and EUS-GD demonstrate high clinical success with no significant differences in adverse event rates. These data can support intraprocedural decision-making for endoscopists performing EUS-GE.
The incidence and predictors of false-negative pancreatobiliary fluorescence in situ hybridization (PB-FISH) in biliary strictures: A prospective study
Aggarwal, Manik , Gores, Gregory J. , Law, Ryan , Martin, John A. , Petersen, Bret T. , Eaton, John E. , Roberts, Lewis R. , Gores, Gregory J. , Vargas, Eric J , Storm, Andrew C , Law, Ryan J, Roberts, Lewis R , Chandrasekhara, Vinay , Aggarwal, Manik , Vargas, Eric J. , Storm, Andrew C. , Dayyeh, Barham K. Abu , Petersen, Bret T. , Ilyas, Sumera I. , Chandrasekhara, Vinay

Hepatology Communications | July 21, 2025 | Volume: 9 | Issue: 8 | Pages: No page available

10.1097/hc9.0000000000000751 Get It

Background: Fluorescence in situ hybridization (FISH) is recommended as part of multimodality sampling in the evaluation of biliary strictures, but can be false negative in 40%–50% cases. The aim of this study was to comprehensively assess predictors of false-negative FISH in patients with biliary strictures. Methods: Patients undergoing tissue sampling for biliary strictures from October 20 to February 22 were prospectively enrolled (NCT04572711). Procedural factors such as sampling techniques, order, and utilization of combination sampling were recorded. Results of an optimized pancreatobiliary FISH panel with locus-specific probes for 1q21, 7p12, 8q24, and 9p21 were reported per guidelines. Statistical analyses were performed using BlueSky Statistics v.10.3.1, R package v8.81. Results: Of 327 patients, 93 (28.5%) were diagnosed with malignancy. A false-negative pancreatobiliary fluorescence in situ hybridization (PB-FISH) was reported in 40 (43.1%) patients. A history of primary sclerosing cholangitis was associated with lower odds of having a false-negative PB-FISH (aOR=0.38, 95% CI=0.16–0.82, p=0.02), whereas a hilar stricture was associated with a significantly higher false-negative PB-FISH in those with cholangiocarcinoma (aOR=3.2 [1.4–7.9], p=0.009). Dilation of biliary strictures prior to brushing was not associated with a lower rate of false-negative PB-FISH. Conclusions: In this prospective study, hilar strictures were more likely to have false-negative PB-FISH. Dilation of strictures did not affect PB-FISH performance. These results can help guide PB-FISH interpretation.
Utilization of an artificial intelligence–enhanced, web‐based application to review bile duct brushing cytologic specimens: A pilot study
Marya, Neil B. , Powers, Patrick, Bois, Melanie C. , Hartley, Christopher , Kerr, Sarah E. , Thangaiah, Judith Jebastin, Cantley, Richard , Gleeson, Ferga C. , Law, Ryan , Martin, John A. , Petersen, Bret T. , Levy, Michael J. , Jebastin, Judith A S , Cantley, Richard , Law, Ryan J, Maleki, Zahra , Pantanowitz, Liron , Petersen, Bret, Marya, Neil B. , Hartley, Christopher P , Norton, Daniel, Dayyeh, Barham K. Abu , Chandrasekhara, Vinay , Gores, Gregory J. , Maleki, Zahra , Petersen, Bret T. , Storm, Andrew C. , Graham, Rondell P.

Cancer Cytopathology | August 29, 2024 | Volume: 132 | Issue: 12 | Pages: 779-787

10.1002/cncy.22898 Get It

Abstract Background The authors previously developed an artificial intelligence (AI) to assist cytologists in the evaluation of digital whole‐slide images (WSIs) generated from bile duct brushing specimens. The aim of this trial was to assess the efficiency and accuracy of cytologists using a novel application with this AI tool. Methods Consecutive bile duct brushing WSIs from indeterminate strictures were obtained. A multidisciplinary panel reviewed all relevant information and provided a central interpretation for each WSI as being “positive,” “negative,” or “indeterminate.” The WSIs were then uploaded to the AI application. The AI scored each WSI as positive or negative for malignancy (i.e., computer‐aided diagnosis [CADx]). For each WSI, the AI prioritized cytologic tiles by the likelihood that malignant material was present in the tile. Via the AI, blinded cytologists reviewed all WSIs and provided interpretations (i.e., computer‐aided detection [CADe]). The diagnostic accuracies of the WSI evaluation via CADx, CADe, and the original clinical cytologic interpretation (official cytologic interpretation [OCI]) were compared. Results Of the 84 WSIs, 15 were positive, 42 were negative, and 27 were indeterminate after central review. The WSIs generated on average 141,950 tiles each. Cytologists using the AI evaluated 10.5 tiles per WSI before making an interpretation. Additionally, cytologists required an average of 84.1 s of total WSI evaluation. WSI interpretation accuracies for CADx (0.754; 95% CI, 0.622–0.859), CADe (0.807; 95% CI, 0.750–0.856), and OCI (0.807; 95% CI, 0.671–0.900) were similar. Conclusions This trial demonstrates that an AI application allows cytologists to perform a triaged review of WSIs while maintaining accuracy.
Utility of methylated DNA markers for the diagnosis of malignant biliary strictures
Cooley, Matthew A. , Schneider, Amber, Fritcher, Emily G. Barr , Milosevic, Dragana , Levy, Michael J. , Bridgeman, Amber R. , Martin, John A. , Petersen, Bret T. , Dayyeh, Barham K. Abu , Law, Ryan , Garimella, Vishal, Jenkins, Sarah M. , Yin, Jun, Roberts, Lewis R. , Kipp, Benjamin R. , Ferrándiz‐Pulido, Carla , Schneider, Amber R, Abu Dayyeh, Barham K , Storm, Andrew C , Law, Ryan J, Vargas, Eric J , Roberts, Lewis R , Kipp, Benjamin , Chandrasekhara, Vinay , Barr Fritcher, Emily G , Bridgeman, Amber R , Levy, Michael J. , Storm, Andrew C. , Vargas, Eric J. , Zemla, Tyler , Gores, Gregory J. , Chandrasekhara, Vinay

Hepatology | June 21, 2024 | Volume: 81 | Issue: 2 | Pages: 453-464

10.1097/hep.0000000000000970 Get It

Background and Aims: Early identification of malignant biliary strictures (MBSs) is challenging, with up to 20% classified as indeterminants after preliminary testing and tissue sampling with endoscopic retrograde cholangiopancreatography. We aimed to evaluate the use of methylated DNA markers (MDMs) from biliary brushings to enhance MBS detection in a prospective cohort. Approach: Candidate MDMs were evaluated for their utility in MBS diagnosis through a series of discovery and validation phases. DNA was extracted from biliary brushing samples, quantified, bisulfite-converted, and then subjected to methylation-specific droplet digital polymerase chain reaction. Patients were considered to have no malignancy if the sampling was negative and there was no evidence of malignancy after 1 year or definitive negative surgical histopathology. Results: Fourteen candidate MDMs were evaluated in the discovery phase, with top-performing and new markers evaluated in the technical validation phase. The top 4 MDMs were TWIST1, HOXA1, VSTM2B, and CLEC11A, which individually achieved AUC values of 0.82, 0.81, 0.83, and 0.78, respectively, with sensitivities of 59.4%, 53.1%, 62.5%, and 50.0%, respectively, at high specificities for malignancy of 95.2%–95.3% for the final biologic validation phase. When combined as a panel, the AUC was 0.86, achieving 73.4% sensitivity and 92.9% specificity, which outperformed cytology and fluorescence in situ hybridization (FISH). Conclusions: The selected MDMs demonstrated improved performance characteristics for the detection of MBS compared to cytology and FISH. Therefore, MDMs should be considered viable candidates for inclusion in diagnostic testing algorithms.
Celiac artery mesenteric fat measurement with endosonography (CAMEUS) reliably correlates with obesity and related comorbidities
Bazerbachi, Fateh , Baroud, Serge , Levy, Michael J. , Maselli, Daniel B. , Bofill-García, Aliana, Law, Ryan , Chandrasekhara, Vinay , Gleeson, Ferga C. , Rajan, Elizabeth , Iyer, Prasad G. , Watt, Kymberly D. , Law, Ryan J, Chandrasekhara, Vinay , Bazerbachi, F , Vargas, Eric J. , Storm, Andrew C. , Dayyeh, Barham K. Abu

Gastroenterology Report | April 26, 2024 | Volume: 12 | Issue: No issue available | Pages: No page available

10.1093/gastro/goae039 Get It

Abstract Background Visceral fat represents a metabolically active entity linked to adverse metabolic sequelae of obesity. We aimed to determine if celiac artery mesenteric fat thickness can be reliably measured during endoscopic ultrasound (EUS), and if these measurements correlate with metabolic disease burden. Methods This was a retrospective analysis of patients who underwent celiac artery mesenteric fat measurement with endosonography (CAMEUS) measurement at a tertiary referral center, and a validation prospective trial of patients with obesity and nonalcoholic steatohepatitis who received paired EUS exams with CAMEUS measurement before and after six months of treatment with an intragastric balloon. Results CAMEUS was measured in 154 patients [56.5% females, mean age 56.5 ± 18.0 years, body mass index (BMI) 29.8 ± 8.0 kg/m2] and was estimated at 14.7 ± 6.5 mm. CAMEUS better correlated with the presence of non-alcoholic fatty liver disease (NAFLD) (R2 = 0.248, P &lt; 0.001) than BMI (R2 = 0.153, P &lt; 0.001), and significantly correlated with metabolic parameters and diseases. After six months of intragastric balloon placement, the prospective cohort experienced 11.7% total body weight loss, 1.3 points improvement in hemoglobin A1c (P = 0.001), and a 29.4% average decrease in CAMEUS (−6.4 ± 5.2 mm, P &lt; 0.001). CAMEUS correlated with improvements in weight (R2 = 0.368), aspartate aminotransferase to platelet ratio index (R2 = 0.138), and NAFLD activity score (R2 = 0.156) (all P &lt; 0.05). Conclusions CAMEUS is a novel measure that is significantly correlated with critical metabolic indices and can be easily captured during routine EUS to risk-stratify susceptible patients. This station could allow for EUS access to sampling and therapeutics of this metabolic region.
Correction to: Endoscopic Ultrasound-Guided Gastrojejunostomy for Superior Mesenteric Artery Syndrome Secondary to Rapid Weight Loss
Alqaisieh, Mohammad , Mahmoud, Tala , Akiki, Karl, Law, Ryan , Law, Ryan J, Storm, Andrew C.

ACG Case Reports Journal | October 11, 2023 | Volume: 9 | Issue: 11 | Pages: e00914

10.14309/crj.0000000000000914 Get It

Risk of post-sphincterotomy bleeding in patients with thrombocytopenia
AbiMansour, Jad P. , Garimella, Vishal, Petersen, Bret T. , Law, Ryan , Martin, John A. , Levy, Michael J. , Law, Ryan J, AbiMansour, Jad , Petersen, Bret T. , Storm, Andrew C. , Dayyeh, Barham K. Abu , Chandrasekhara, Vinay

Therapeutic Advances in Gastrointestinal Endoscopy | September 25, 2023 | Volume: 16 | Issue: No issue available | Pages: No page available

10.1177/26317745231200971 Get It

Background: Reports suggest that the rate of adverse events (AEs) post-endoscopic sphincterotomy (ES) to be as high as 10%, with gastrointestinal bleeding being most common after post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. Objective: The aim of this study was to characterize the incidence of bleeding in patients with thrombocytopenia following ES. Design: Retrospective observational cohort study. Methods: Patients with thrombocytopenia (defined as <150,000 platelets/μL) who underwent ES between May 2017 and December 2020 were identified at a tertiary care medical center. The incidence of immediate (intraprocedural oozing >5 min or requiring intervention) or delayed (clinical bleeding with associated hemoglobin drop within 14 days) post-ES bleeding was determined via manual chart review. Results: A total of 221 patients with a mean platelet count of 108,000 ± 13,000 platelets/μL underwent ERCP with ES. Immediate bleeding occurred in 11 (5%) patients with no significant drop in hemoglobin or transfusion requirement. Two patients (0.9%), both of whom were noted to have immediate bleeding, also developed delayed bleeding. Presence of malignancy was associated with an increased risk of bleeding (36.4% versus 11.4%, p = 0.037) while platelet count was not. Conclusion: In a cohort of patients with thrombocytopenia, rates of immediate and delayed bleeding are similar to previously reported AE rates of ES in the general patient population. Careful attention should be given to patients with a history of active malignancy as well as those who develop immediate bleeding as they appear to be at increased risk for bleeding complications.
Endoscopic Ultrasound-Guided Gastrojejunostomy for Superior Mesenteric Artery Syndrome Secondary to Rapid Weight Loss
Mahmoud, Tala , Akiki, Karl, Law, Ryan , Law, Ryan J, Storm, Andrew C. , Akiki, Karl

ACG Case Reports Journal | October 6, 2022 | Volume: 9 | Issue: 10 | Pages: e00868

10.14309/crj.0000000000000868 Get It

ABSTRACT A 19-year-old man diagnosed with diffuse large B-cell lymphoma undergoing chemotherapy presented for recurrent emesis and weight loss. Imaging studies of the abdomen demonstrated features of superior mesenteric artery syndrome. The patient deferred conservative treatment options and was deemed not to be a surgical candidate. Endoscopic ultrasound-guided gastroenterostomy using a lumen-apposing metal stent was performed to bypass the obstruction. Subsequently, the patient's oral intake and weight significantly improved. The stent was removed 6 months after placement with resolution of superior mesenteric artery syndrome symptoms.
Histological assessment of new cholangioscopy-guided forceps in ERCP biliary stricture sampling: a blinded comparative study
Chen, Zongming Eric, Abusaleh, Rami R., Martin, John A. , Law, Ryan , Levy, Michael J. , Petersen, Bret T. , Law, Ryan J, Petersen, Bret, Vargas, Eric J. , Wang, Yaohong , Abusaleh, Rami , Storm, Andrew C. , Dayyeh, Barham K. Abu , Levy, Michael J. , Petersen, Bret T. , Chandrasekhara, Vinay

Endoscopy International Open | September 14, 2022 | Volume: 10 | Issue: 09 | Pages: E1233-E1237

10.1055/a-1897-4686 Get It

Abstract Background and study aims Obtaining quality tissue during ERCP biliary stricture sampling is of paramount importance for a timely diagnosis. While single-operator cholangioscopy (SOC)-guided biopsies have been suggested to be the superior biliary tissue acquisition modality given direct tissue visualization, less is known about the specimen histological quality. We aimed to analyze the specimen quality of SOC biopsies and compare the new generation forceps with prior “legacy” forceps. Patients and methods Patients who underwent SOC from January 2017-August 2021 for biliary sampling were reviewed. In February 2020, the SOC-guided biopsy forceps were changed from legacy SpyBite to the SpyBite Max forceps (max). Specimens were assessed by blinded pathologists for crush artifact (none, mild, or severe) and gross size (greatest dimension in mm). Crush artifact and gross size were compared between the two groups. The diagnostic performance characteristics for cholangiocarcinoma (CCA), were assessed in an exploratory fashion. Results Eighty-one patients (max = 27, legacy = 54) with similar baseline characteristics were included in this study. On blinded pathological assessment, 58 % had crush artifact, without significant differences between the two groups (Max 63 % vs. Legacy 56 %; P = 0.64). A similar mean specimen size was found (max 3 mm vs. legacy 3.2 mm; P = 0.24). The overall prevalence of CCA was 40 %. The sensitivity, specificity, positive predictive value, and negative predictive value of the entire cohort using a combination of cytology, fluorescence in situ hybridization, and SOC-guided biopsies were 78.1 %, 91.8 %, 86.2 %, and 86.5 %, respectively. No difference between legacy or max groups was found. Conclusions A high rate of crush artifact was found in SOC-guided biopsy specimens. Further investigation regarding proper biopsy technique and handling is necessary to increase the diagnostic yield with SOC-guided biopsies.
Efficacy and safety of endoscopic ultrasound-guided gastrojejunostomy in patients with malignant gastric outlet obstruction and ascites
Mahmoud, Tala , Law, Ryan , Jaruvongvanich, Veeravich , Ghazi, Rabih , Abusaleh, Rami , Levy, Michael J. , Truty, Mark J. , Law, Ryan J, Storm, Andrew C. , Vargas, Eric J. , Bazerbachi, Fateh , Levy, Michael J. , Chandrasekhara, Vinay , Dayyeh, Barham K. Abu

Endoscopy International Open | May 13, 2022 | Volume: 10 | Issue: 05 | Pages: E670-E678

10.1055/a-1797-9318 Get It

Abstract Background and study aims Endoscopic ultrasound-guided gastrojejunostomy (EUS-GJ) is an endoscopic procedure for treating gastric outlet obstruction (GOO). Limited data exist regarding the safety and efficacy of EUS-GJ in patients with malignant GOO with ascites. Thus, we aimed to study the outcomes and safety of EUS-GJ in GOO patients with vs. without ascites. Patients and methods This is a retrospective cohort study of patients with malignant GOO who underwent successful EUS-GJ at a tertiary care academic center. Primary outcomes included the efficacy and safety of EUS-GJ. Secondary outcomes included 30-day readmission, reintervention, and survival utilizing Kaplan-Meier analysis. Results A total of 55 patients (mean age of 67.0 ± 11.3 years, 40.0 % female) who underwent EUS-GJ, of whom 24 had ascites (small in 22, large in 2) were included. Clinical success was achieved in 91.7 % and 93.5 % (P = 1.00) of patients with and without ascites, respectively. A higher rate of adverse events (AEs) was noted in patients with ascites but this was not statistically significant (37.5 % vs. 19.4 %, P = 0.13). Four patients in the ascites group (16.6 %) developed clinical evidence of peritonitis or sepsis post-EUS-GJ. Eight patients with ascites developed worsening ascites within a month of EUS-GJ. In contrast, only one patient without ascites developed evidence of new ascites. The median survival of patients was not significantly different between the two groups (patients with ascites: 129 days vs. patients without ascites: 180 days, (P = 0.12). Conclusions The efficacy EUS-GJ in the presence of ascites is promising; however, the safety profile remains concerning given the high rate of AEs, specifically peritonitis and sepsis.