Browsing by Author "Ponugoti, Prasanna"

Now showing 1 - 4 of 4
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    Faster colonoscope withdrawal time without impaired detection using EndoRings
    (Thieme, 2018-08) Thygesen, John C.; Ponugoti, Prasanna; Tippins, William W.; Garcia, Jonathan R.; Sullivan, Andrew W.; Broadley, Heather M.; Rex, Douglas K.; Medicine, School of Medicine
    Background and study aims:  Mucosal exposure devices on the colonoscope tip have improved detection. We evaluated detection and procedure times in colonoscopies performed with EndoRings. Patients and methods:  We had 14 endoscopists in a university practice trial EndoRings. We compared detection and procedure times to age- and indication-matched procedures by the same endoscopists. Results:  There were 137 procedures with EndoRings. The adenoma detection rate was 44 % with EndoRings vs. 39 % without ( P  = 0.39). Mean adenomas per colonoscopy (standard deviation) was 1.2 (2.3) with EndoRings vs. 0.9 (1.6) without ( P  = 0.055). Mean insertion time with EndoRings was 6.2 (3.2) minutes vs. 6.6 (6.7) minutes without ( P  = 0.81). Mean withdrawal time with EndoRings in all patients with or without polypectomy was 12.2 (5.3) minutes and 16.1 (10.3) minutes without ( P  = 0.0005). Conclusion:  EndoRings may allow faster withdrawal during colonoscopy without any reduction in detection. Prospective trials with mucosal exposure devices targeting procedure times as primary endpoints are warranted.
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    Neoplasia at 10-year follow-up screening colonoscopy in a private U.S. practice: comparison of yield to first-time examinations
    (Elsevier, 2017) Rex, Douglas K.; Ponugoti, Prasanna; Johnson, Cynthia S.; Kittner, Lisa; Yanda, Randy; Department of Medicine, IU School of Medicine
    Background and Aims Prior studies assessing the yield of a second screening colonoscopy performed 10 years after an initial negative screening colonoscopy did not include a control group of persons undergoing their first screening colonoscopy during the same time interval. Our aim was to describe the incidence of neoplasia at a second screening colonoscopy (performed at least 8 years after the first colonoscopy) in average risk individuals and compare it with the yield of first screening examinations performed during the same time interval. Methods Review of a database of outpatient screening colonoscopies performed between January 2010 and December 2015 in an Atlanta private practice. Results A total of 2105 average risk individuals underwent screening colonoscopy, including 470 individuals (53.6% female; mean age 64.0 ± 3.9 years) who underwent a second screening examination. In those undergoing second screening, the mean interval between examinations was 10.4 years (±1.1; range 8-15 years). At second screening, the polyp detection rate (PDR), adenoma detection rate (ADR) and advanced neoplasm rate (ANR) were 44.7%, 26.6%, and 7.4%, respectively. Of 40 advanced neoplasms in 35 individuals, 33 (82.5%) were proximal to the sigmoid colon, and there were no cancers. During the same interval, 1635 individuals (49.4% female; mean age 52.6 ± 3.4 years) underwent their first screening colonoscopy. The PDR, ADR and ANR were 53.5%, 32.2%, and 11.7%, respectively. Of 243 advanced neoplasms in 192 individuals, 152 (62.6%) were proximal to the sigmoid colon, and there were no cancers. After adjustment for age, gender, body mass index, and endoscopist, PDR, ADR, and ANR were all lower at the second screening colonoscopies than at first-time colonoscopies (all p<0.001). Conclusions Despite being 10 years older, persons with a negative screening colonoscopy 10 years earlier had numerically lower rates of adenomas and advanced neoplasms at their second screening examination compared with patients in the same practice undergoing their first screening colonoscopy, and they had no cancers. The fraction of advanced neoplasms that were proximal to the sigmoid was high in both first and second screenings. These results support the safety of the recommended 10-year interval between colonoscopies in average risk persons with an initial negative examination.
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    Prevalence of sessile serrated adenoma/polyp in hyperplastic appearing diminutive rectosigmoid polyps
    (Elsevier, 2016) Ponugoti, Prasanna; Lin, Jingmei; Odze, Robert; Snover, Dale; Kahi, Charles; Rex, Douglas K.; Department of Medicine, IU School of Medicine
    Background The American Society for Gastrointestinal Endoscopy recommends that distal colon hyperplastic lesions can be left in place without resection if adenomatous histology can be excluded with > 90% negative predictive value. However, some of the lesions could be sessile serrated adenoma/polyp (SSA/P), which is also precancerous. Aim Describe the prevalence of SSA/P in hyperplastic appearing diminutive rectosigmoid polyps. Methods We prospectively placed 513 consecutive diminutive rectosigmoid polyps that appeared hyperplastic to an expert endoscopist in individual bottles for pathologic examination. Each polyp was examined by 3 expert gastrointestinal pathologists. Results The prevalence of SSA/P in the study polyps ranged from 0.6% to 2.1%. The endoscopists lowest negative predictive value for the combination of adenomas plus SSA/P was 96.7% Conclusions The prevalence of SSA/P in diminutive rectosigmoid hyperplastic appearing polyps is very low. These results support the safety and feasibility of a “do not resect” policy for diminutive hyperplastic appearing rectosigmoid polyps.
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    The “valley sign” in small and diminutive adenomas: prevalence, interobserver agreement, and validation as an adenoma marker
    (Elsevier, 2016) Rex, Douglas K.; Ponugoti, Prasanna; Kahi, Charles; Department of Medicine, IU School of Medicine
    Background Classification schemes for differentiation of conventional colorectal adenomas from serrated lesions rely on patterns of blood vessels and pits. Morphologic features have not been validated as predictors of histology. Aim Describe the prevalence of the “valley sign” and validate it as a marker of conventional adenomas Methods Three experts judged the prevalence of the valley sign in 301 consecutive small adenomas. Medical students were taught to recognize the valley and tested on their recognition of the valley sign. Consecutive diminutive polyps were video-recorded and used to validate the association of the valley sign with conventional adenomas. Results The prevalence of the valley sign in 301 consecutive adenomas <10 mm in size, determined by 3 experts, ranged from 35% to 50%. Kappa values for agreement among the 3 experts were 0.557, 0.679, and 0.642. Ten medical students were taught to interpret the valley sign and recognized it with accuracy of 96% or higher in 50 selected photographs of diminutive polyps. Four medical students evaluated video-recordings of 170 consecutive diminutive polyps for the presence of the valley sign. Kappa values for the interpretation of the valley sign ranged from 0.52 to 0.68 among the students. The sensitivity of the valley sign for adenoma ranged from 40.2% to 54.9%, and specificity ranged from 90.2% to 91.7%. The valley sign was strongly associated with adenomas (p<0.0001). Conclusions The valley sign is insensitive but highly specific for conventional adenoma in diminutive polyps. It may enhance classification schemes for differentiation of adenomas from serrated lesions based on vessels and pits.