Browsing by Author "Lahr, Rachel E."

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    Assessment of Submucosal Distortion and Mass Effect Seen at Follow-up After Colorectal Endoscopic Mucosal Resection with ORISE
    (Elsevier, 2022-05) Lahr, Rachel E.; DeWitt, John M.; Zhang, Dongwei; Rex, Douglas K.; Medicine, School of Medicine
    Recovery from spinal cord injury (SCI) and other central nervous system (CNS) trauma is hampered by limits on axonal regeneration in the CNS. Regeneration is restricted by the lack of neuron-intrinsic regenerative capacity and by the repressive microenvironment confronting damaged axons. To address this challenge, we have developed a therapeutic strategy that co-targets kinases involved in both extrinsic and intrinsic regulatory pathways. Prior work identified a kinase inhibitor (RO48) with advantageous polypharmacology (co-inhibition of targets including ROCK2 and S6K1), which promoted CNS axon growth in vitro and corticospinal tract (CST) sprouting in a mouse pyramidotomy model. We now show that RO48 promotes neurite growth from sensory neurons and a variety of CNS neurons in vitro, and promotes CST sprouting and/or regeneration in multiple mouse models of spinal cord injury. Notably, these in vivo effects of RO48 were seen in several independent experimental series performed in distinct laboratories at different times. Finally, in a cervical dorsal hemisection model, RO48 not only promoted growth of CST axons beyond the lesion, but also improved behavioral recovery in the rotarod, gridwalk, and pellet retrieval tasks. Our results provide strong evidence for RO48 as an effective compound to promote axon growth and regeneration. Further, they point to strategies for increasing robustness of interventions in pre-clinical models.
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    Audit of hemostatic clip use after colorectal polyp resection in an academic endoscopy unit
    (Thieme, 2024-04-23) Stark, Easton M.; Lahr, Rachel E.; Shultz, Jeremiah; Vemulapalli, Krishna C.; Guardiola, John J.; Rex, Douglas K.; Medicine, School of Medicine
    Background and study aims Prophylactic closure of endoscopic resection defects reduces delayed hemorrhage after resection of non-pedunculated colorectal lesions ≥ 20 mm that are located proximal to the splenic flexure and removed by electrocautery. The risk of delayed hemorrhage after cold (without electrocautery) resection is much lower, and prophylactic clip closure after cold resection is generally unnecessary. The aim of this study was to audit clip use after colorectal polyp resection in routine outpatient colonoscopies at two outpatient centers within an academic medical center. Patients referred for resection of known lesions were excluded. Patients and methods Retrospective chart analysis was performed as part of a quality review of physician adherence to screening and post-polypectomy surveillance intervals. Results Among 3784 total lesions resected cold by 29 physicians, clips were placed after cold resection on 41.7% of 12 lesions ≥ 20 mm, 19.3% of 207 lesions 10 to 19 mm in size, and 2.8% of 3565 lesions 1 to 9 mm in size. Three physicians placed clips after cold resection of lesions 1 to 9 mm in 18.8%, 25.5%, and 45.0% of cases. These physicians accounted for 8.1% of 1- to 9-mm resections, but 69.7% of clips placed in this size range. Electrocautery was used for 3.1% of all resections. Clip placement overall after cold resection (3.9%) was much lower than after resection with electrocautery (71.1%), but 62.4% of all clips placed were after cold resection. Conclusions Audits of clip use in an endoscopy practice can reveal surprising findings, including high and variable rates of unnecessary use after cold resection. Audit can potentially reduce unnecessary costs, carbon emissions, and plastic waste.
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    Characterization of endoscopic features and histology of a distinct mucosal transition zone on the ileocecal valve (with video)
    (Elsevier, 2023-09) Rex, Douglas K.; Lahr, Rachel E.; Guardiola, John J.; Dewitt, John M.; Zhang, Dongwei; Medicine, School of Medicine
    Background and Aims We have endoscopically encountered a zone of transitional mucosa between the colonic and ileal mucosa located in a 3- to 10-mm-wide ring around the ileocecal valve (ICV) orifice. We aimed to describe the features of the ICV transitional zone mucosa. Methods We used videos and photographs from normal ICVs and biopsy samples from normal colonic mucosa, transitional zone mucosa, and normal ileal mucosa to characterize the endoscopic and histologic features of the ICV transitional zone mucosa. Results The ICV transitional zone is identifiable on every ICV without a circumferential adenoma or inflammation that obliterates the zone. The zone is characterized endoscopically by an absence of villi, which distinguishes it from the ileal mucosa, but the pits are more tubular and with more prominent blood vessels compared with normal colonic mucosa. Histologically, the villi of the transitional zone are blunted, and the amount of lymphoid tissue is intermediate between the colonic mucosa and ileal mucosa. Conclusions This is the first description of the normal transitional zone of mucosa on the ICV. This zone has unique endoscopic features that should be recognized by colonoscopists and that can potentially create difficulty in identifying the margins of adenomas located on the ICV.
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    Cold versus hot snare resection with or without submucosal injection of 6-15 mm colorectal polyps: a randomized controlled trial
    (ScienceDirect, 2022) Rex, Douglas K.; Anderson, Joseph C.; Pohl, Heiko; Lahr, Rachel E.; Judd, Stephanie; Antaki, Fadi; Lilley, Kirthi; Castelluccio., Peter F.; Vemulapalli, Krishna C.; Medicine, School of Medicine
    Background and aims Cold snare resection of colorectal lesions has been found safe and effective for an expanding set of colorectal lesions. In this study, we sought to understand the efficacy of simple cold snare resection and cold endoscopic mucosal resection (EMR), versus hot snare resection and hot EMR for colorectal lesions 6-15 mm in size. Methods At three U.S. centers, 235 patients with 286 colorectal lesions 6-15 mm in size were randomized to cold snaring, cold EMR, hot snaring, or hot EMR for non-pedunculated colorectal lesions 6-15 mm in size. The primary outcome was complete resection determined by 4 biopsies from the defect margin and 1 biopsy from the center of the resection defect. Results The overall incomplete resection rate was 2.4% (95% CI 0.8-7.5%). All 7 incompletely removed polyps were 10-15 mm in size and removed by hot EMR (n = 4, 6.2%), hot snare (n = 2, 2.2%), or cold EMR (n = 1, 1.8%). Cold snaring had no incomplete resections, required less procedural time than the other methods, and was not associated with serious adverse events. Conclusion Cold snaring is a dominant resection technique for non-pedunculated colorectal lesions 6-15 mm in size.
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    A comparison of 2 distal attachment mucosal exposure devices: a noninferiority randomized controlled trial
    (Elsevier, 2019) Rex, Douglas K.; Sagi, Sashidhar V.; Kessler, William R.; Rogers, Nicholas A.; Fischer, Monika; Bohm, Matthew E.; Dewitt, John M.; Lahr, Rachel E.; Searight, Meghan P.; Sullivan, Andrew W.; McWhinney, Connor D.; Garcia, Jonathan R.; Broadley, Heather M.; Vemulapalli, Krishna C.; Medicine, School of Medicine
    Background and Aims Endocuff and Endocuff Vision are effective mucosal exposure devices for improving polyp detection during colonoscopy. AmplifEYE is a knock-off device that appears similar to the Endocuff devices but has received minimal clinical testing. Methods We performed a randomized controlled clinical trial using a noninferiority design to compare Endocuff Vision with AmplifEYE. Results The primary endpoint of adenomas per colonoscopy was similar in AmplifEYE at 1.63 (2.83) versus 1.51 (2.29) with Endocuff Vision; p=0.535. The 95% lower confidence limit was 0.88 for ratio of means, establishing noninferiority of AmplifEYE (p=0.008). There was no difference between the arms in mean insertion time, and mean inspection time (withdrawal time minus polypectomy time and time for washing and suctioning) was shorter with AmplifEYE (6.8 minutes vs 6.9 minutes, p=0.042). Conclusions AmplifEYE is noninferior to Endocuff Vision for adenoma detection. The decision of which device to use can be based on cost. Additional comparisons of AmplifEYE to Endocuff by other investigators are warranted.
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    Endoscopy staff are concerned about acquiring COVID-19 infection when resuming elective endoscopy
    (Elsevier, 2020) Rex, Douglas K.; Vemulapalli, Krishna C.; Lahr, Rachel E.; McHenry, Lee; Sherman, Stuart; Al-Haddad, Mohammad; Medicine, School of Medicine
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    Frequency and nature of endoscopic and pathologic errors leading to referral for endoscopic resection to a tertiary center
    (Thieme, 2022-12-15) Lahr, Rachel E.; McWhinney, Connor D.; Cummings, Oscar W.; Rex, Douglas K.; Medicine, School of Medicine
    Background and study aims: We anecdotally encounter cases where referring endoscopists made errors in endoscopic interpretation of a colorectal lesion, sometimes combined with pathology errors at the referring centers, resulting in referral to our center for endoscopic resection. In this paper, we describe the frequency and nature of endoscopic and pathology errors leading to consultation for endoscopic resection. Patients and methods: Review of 760 consecutive referrals to our center over a 26-month interval. Results: In total, 28 (3.7 %) of all referred patients had ≥ 1 lesion that did not require any resection after investigation. There were 12 cases (1.6 % of all referrals) involving errors by both the referring endoscopist and the pathologist at the referring center. Errors commonly involved the ileocecal valve, lipomas, and mucosal prolapse changes. There were 15 additional referrals (2.0 % of all referrals) where no neoplastic lesion was identified at our center and either no biopsy was taken at the referring center (n = 9 patients, 10 lesions), the patient was referred although biopsy showed no neoplasia (n = 6), or the referring doctor correctly interpreted the lesion (lipoma), but the outside pathologist incorrectly reported adenoma (n = 1). Conclusions: Endoscopists at tertiary centers should expect referrals to clarify the nature of colorectal lesions as neoplastic or non-neoplastic. Community endoscopists with equivocal endoscopic findings and unexpected or equivocal pathology results can consider pathology review at their center or at an expert center before referral for endoscopic or surgical resection.
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    Frequency of serrated polyposis syndrome recognition by community endoscopists
    (Thieme, 2023-10-06) McWhinney, Connor D.; Lahr, Rachel E.; Rex, Douglas K.; Medicine, School of Medicine
    Background and study aims: Some data indicate serrated polyposis syndrome (SPS) is underdiagnosed. We determined the frequency of SPS diagnosis by community endoscopists prior to referral to a tertiary center. Patients and methods: We performed a retrospective analysis of a prospectively collected database of SPS patients at a tertiary academic hospital. There were 212 patients who were referred to our center for resection of one or more lesions detected at a prior colonoscopy and who had records available that allowed determination of whether SPS was diagnosed before referral. Results: Only 25 of 212 patients (11.8%) had a diagnosis or suspicion of a polyposis syndrome prior to referral, and only 12 patients (5.7%) had a specific SPS diagnosis made prior to referral. Among 187 patients diagnosed at our center, 39 had sufficient serrated lesions removed and documented in outside records to meet SPS criteria prior to referral, but the diagnosis was not made by the referring physician despite adequate numbers of lesions resected. The remaining cases required lesions removed at our center to meet SPS diagnostic criteria. Limitations were a single center, single expert endoscopist. Conclusions: SPS is the most common colorectal polyposis syndrome, but it remains underdiagnosed by community endoscopists. Underdiagnosis may contribute to post-colonoscopy colorectal cancer in patients with SPS.
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    Impact of a ring fitted cap on insertion time and adenoma detection: a randomized controlled trial
    (Elsevier, 2019) Rex, Douglas K.; Kessler, William R.; Sagi, Sashidhar V.; Rogers, Nicholas A.; Fischer, Monika; Bohm, Matthew E.; Wo, John M.; Dewitt, John M.; McHenry, Lee; Lahr, Rachel E.; Searight, Meghan P.; MacPhail, Margaret; Sullivan, Andrew W.; McWhinney, Connor D.; Vemulapalli, Krishna C.; Medicine, School of Medicine
    Background and Aims: Devices for flattening colon folds can improve polyp detection at colonoscopy. However, there are few data on the endoscopic ring fitted cap (EndoRings, EndoAid, Caesarea, Israel). We sought to compare adenoma detection with EndoRings with that of standard high-definition colonoscopy. Methods: A single-center randomized controlled trial of 562 patients (284 randomized to EndoRings and 278 to standard colonoscopy) at 2 outpatient endoscopy units in the Indiana University Hospital system. Adenoma detection was the primary outcome measured as adenoma detection rate (ADR) and adenomas per colonoscopy (APC). We also compared sessile serrated polyp detection rate (SSPDR), insertion times, withdrawal times, and ease of passage through the sigmoid colon. Results: EndoRings was superior to standard colonoscopy in terms of APC (1.46 vs 1.06, p=0.025) but there were no statistically significant differences in ADR or SSPDR. Mean withdrawal time (in patients with no polyps) was shorter and insertion time (all patients) was longer in the EndoRings arm by 1.8 minutes and 0.75 minutes, respectively. One provider had significantly higher detection with EndoRings and contributed substantially to the overall results. Conclusions: EndoRings can increase adenoma detection without significant increase in procedure time, but the effect varies between operators. EndoRings slows colonoscope insertion.
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    Impact of changing diagnostic criteria on the diagnosis of serrated polyposis syndrome
    (Thieme, 2023-01-04) McWhinney, Connor D.; Lahr, Rachel E.; Lee, Christopher J.; El-Rahyel, Ahmed; Rex, Douglas K.; Medicine, School of Medicine
    Background and study aims: The World Health Organization criteria for serrated polyposis syndrome (SPS) were established in 2010 and modified in 2019. Neither set of criteria have been validated against genetic markers or proven to be the optimal criteria for defining colorectal cancer risk in patients with serrated colorectal lesions. In this study, we sought to gain insight into how frequently the change in SPS criteria in 2019 impacted the diagnosis of SPS. Patients and methods: We reviewed 279 patients with SPS diagnosed between 2010 and 2019 using the 2010 criteria (n = 163) or since 2019 using the 2019 criteria (n = 116). We reviewed whether patients in each group met the diagnosis of SPS by the alternative criteria. Results: Of those diagnosed using 2010 criteria, 5.5 % did not meet 2019 criteria. Of those diagnosed by 2019 criteria, 10.3 % did not meet 2010 criteria. Conclusions: Most patients with SPS in our database met the diagnosis of SPS by both 2010 and 2019 criteria, with only 5 % to 10 % of patients in each cohort not meeting the alternative diagnostic criteria.