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Myers, Amanda A.

https://orcid.org/0000-0002-5219-2978

Mayo Clinic

University of Iowa Health Care

Citations 8

Computed tomography ‐derived extracellular volume fraction is associated with high‐grade recurrence in non‐muscle‐invasive bladder cancer treated with intravesical gemcitabine and docetaxel
Chakra, Mohamad Abou, Alsamarah, Issa, Hougen, Helen Y., Brown, James A. , Marchetti, Kathryn , Henning, Grant , Duquesne, Igor , Buhaş, Bogdan Adrian , O’Donnell, Michael A. , Hougen, Helen Y. , Duquesne, Igor , Buhas, Bogdan Adrian , O'Donnell, Michael A , Henning, Grant M , Chakra, Mohamad Abou , Zakharia, Yousef , Myers, Amanda A. , Mott, Sarah L.

BJU International | May 28, 2026 | Volume: 138 | Issue: 2 | Pages: 306-314

10.1111/bju.70319 Get It

Objectives To evaluate whether extracellular volume (ECV) fraction derived from contrast‐enhanced computed tomography (CT) is associated with recurrence risk in patients with treatment‐naïve high‐risk non‐muscle‐invasive bladder cancer (HR‐NMIBC) receiving intravesical gemcitabine/docetaxel (Gem/Doce) therapy. Patients and Methods This retrospective cohort study, conducted at a tertiary referral centre, included 103 patients with HR‐NMIBC treated with intravesical Gem/Doce between 2012 and 2024. All patients underwent pre‐resection contrast‐enhanced CT with an equilibrium phase (~3 min post‐injection). Tumour ECV fraction (%) was calculated using the formula: ECV = (ΔHUtumour/ΔHUaorta) × (1 − haematocrit) × 100, where Δ Hounsfield units (HU) represents the change in attenuation between non‐contrast and equilibrium phases. Regions of interest were manually placed in the tumour and abdominal aorta, and haematocrit values obtained within ±10 days were used. Associations between clinical variables, ECV, and recurrence were evaluated using Cox proportional hazards models, with discrimination assessed by Uno's C‐statistic. Results The median (interquartile range) follow‐up was 17 (10–25) months. High‐grade recurrence‐free survival (HG‐RFS) was 76% at 12 months and 69% at 24 months. CT‐derived ECV was the only variable significantly associated with HG‐RFS (hazard ratio 1.05, 95% confidence interval 1.03–1.08), demonstrating strong discrimination (C‐statistic, 0.81; P < 0.01). A 15% threshold offered the best sensitivity–specificity trade‐off (~70% each) for predicting HG‐RFS at 12 and 24 months. Patients with ECV ≤15% had markedly better HG‐RFS than those with ECV >15% at 24 months (88% vs 41%). Conclusions The CT‐derived ECV is a practical, first‐of‐its‐kind imaging biomarker associated with recurrence risk and useful for risk stratification in patients with HR‐NMIBC treated with intravesical Gem/Doce, a regimen increasingly used in the setting of global Bacillus Calmette‐Guérin shortages and intolerance. ECV can be rapidly quantified from routine contrast‐enhanced CT using standard picture archiving and communication system (PACS) tools, without additional imaging or proprietary software, making it a feasible metric for integration into risk‐adapted management pending large‐scale validation with extended follow‐up.
Peritoneal Window Technique: A Novel Sutureless Technique to Decrease the Rate of Symptomatic Lymphocele after Robot-Assisted Radical Prostatectomy with Extended Pelvic Lymph Node Dissection
Qualkenbush, Eric , Lee, Yeonsoo Sara , Kahn, Amanda E. , Qosja, Neda, Hochwald, Alex, Zganjar, Andrew , Pathak, Ram , Pak, Raymond , Qualkenbush, Eric , Pak, Raymond W. , Lee, Yeonsoo S, Kahn, Amanda , Sara Lee, Yeonsoo , Pak, Ray , Myers, Amanda A.

Journal of Endourology | June 10, 2025 | Volume: 39 | Issue: 10 | Pages: 1028-1032

10.1089/end.2025.0093 Get It

Introduction: Robot-assisted radical prostatectomy (RARP) with extended pelvic lymph node dissection (PLND) represents the gold standard surgical treatment for high-risk localized prostate cancer. PLND carries the risk of lymphocele formation, which can lead to complications such as deep vein thrombosis (DVT), infection, and voiding dysfunction. Many techniques have been described to minimize lymphocele formation, yet no method has seen widespread use or been described as sutureless. The objective of this study is to describe the novel, sutureless peritoneal window (PWIN) technique and assess its efficacy in lymphocele prophylaxis for extended PLND. Methods: This was a retrospective review of patients with high-risk prostate cancer undergoing RARP with extended PLND by a single surgeon from 2018 to 2024. PLND was carried out in the usual manner with bipolar cautery. PWIN technique is performed by excising a 3 × 5 cm PWIN over the lymphadenectomy bed to maintain lymphatic communication with the abdominal cavity. The primary outcome was a comparison between the incidence of symptomatic lymphoceles (SLs) with PWIN vs standard technique. SLs were defined as lymphoceles presenting with pain, DVT, voiding dysfunction, or infectious symptoms. Patients with asymptomatic lymphoceles were excluded. Results: Our study included 199 patients who underwent RARP with extended PLND. There were 46 patients (23.1%) in the standard approach group and 153 patients (76.9%) in the PWIN group. We identified 5/46 (10.9%) SLs in the standard technique, which were significantly higher than the 3/153 (2.0%) observed in the PWIN group (p = 0.017). There was no difference between the standard and PWIN cohorts regarding symptomology or treatment of their lymphocele. Conclusion: This study describes a novel, sutureless PWIN technique that significantly decreases SL after extended PLND. This technique offers a practical, time-efficient, and cost-effective alternative for lymphocele prevention. Future prospective studies are warranted to validate these findings.
Complex Urethral Diverticulectomy: Is a Synchronous Prophylactic Autologous Fascial Sling Needed?
Schaaf, Amanda L., Lee, Yeonsoo Sara , Myers, Amanda A. , Schommer, Jared , Gonzalez, Giovanni, Chen, Anita, Petrou, Steven P. , Lee, Yeonsoo S, Petrou, Steven , Sara Lee, Yeonsoo , Myers, Amanda

Urogynecology | May 26, 2023 | Volume: 29 | Issue: 6 | Pages: 552-557

10.1097/spv.0000000000001311 Get It

Importance Urethral diverticulectomy is performed with or without concomitant pubovaginal sling (PVS). Patients with complex UD are more frequently offered concomitant PVS. However, there is paucity of literature comparing postoperative incontinence rates for patients with simple versus complex UD. Objective The objective of this study is to examine postoperative stress urinary incontinence (SUI) rates after Urethral Diverticulectomy without concomitant PVS for both complex and simple cases. Study Design A retrospective cohort study was conducted among 55 patients who underwent Urethral Diverticulectomy from 2007 to 2021. Preoperative SUI was patient-reported and confirmed with cough stress test result. Complex cases were defined as circumferential or horseshoe configurations, prior diverticulectomy, and/or anti-incontinence procedure. Primary outcome was postoperative SUI. Secondary outcome was interval PVS. Complex and simple cases were compared using the Fisher exact test. Results Median age was 49 years (interquartile range, 36–58 years). Median follow-up was 5.4 months (IQR, 2–24 months). Thirty of 55 (55%) cases were simple, and 25 of 55 (45%) complex. Preoperative SUI was present in 19/57 (35%) (11 complex vs 8 simple, P = 0.25). Stress urinary incontinence persisted postoperatively in 10 of 19 (52%) (6 complex vs 4 simple, P = 0.48). De novo SUI occurred in 7 of 55, 12% (4 complex vs 3 simple, P = 0.68). Overall, 17 of 55 (31%) patients had postoperative SUI (10 complex vs 7 simple, P = 0.24). Of those, 8 of 17 underwent subsequent PVS placement (P = 0.71) and 9 of 17 had resolution of pad use after physical therapy (P = 0.27). Conclusions We did not find evidence of an association between complexity and postoperative SUI. Age at surgery and preoperative frequency were the strongest predictors of postoperative SUI in this cohort. Our findings suggest successful complex urethral diverticulum repair does not require concomitant PVS.
Intraoperative Blood Transfusion Is Associated With Increased Risk of Venous Thromboembolism After Radical Cystectomy
Myers, Amanda A. , Frank, Igor, Shah, Paras , Tarrell, Robert F., Baird, Bryce , Dora, Chandler , Karnes, R. Jeffrey , Thompson, R. Houston, Tollefson, Matthew K. , Boorjian, Stephen A. , Lyon, Timothy D. , Myers, Amanda , Dora, Chandler D , Lyon, Timothy D

Journal of Urology | November 29, 2022 | Volume: 209 | Issue: 3 | Pages: 525-531

10.1097/ju.0000000000003094 Get It

Urinary Outcomes After Magnetic Resonance Imaging-Guided Whole-Gland Transurethral Ultrasound Ablation for Prostate Cancer: Comparison of Suprapubic Tube to Indwelling Urethral Catheter
Myers, Amanda A. , Dora, Chandler , Dora, Chandler D , Myers, Amanda , Rabinowitz, Matthew J., Haney, Nora M. , Pavlovich, Christian P.

Journal of Endourology | August 26, 2022 | Volume: 37 | Issue: 1 | Pages: 1-7

10.1089/end.2022.0214 Get It

Background: MRI-guided transurethral ultrasound ablation (TULSA) is under investigation for whole-gland ablation of low- and intermediate-risk prostate cancer. The ideal method for post-TULSA bladder drainage through postoperative suprapubic tube (SPT) vs indwelling urethral catheter (UC) has not been established. The objective of this study was to evaluate urinary outcomes after whole-gland TULSA, comparing postoperative SPT with UC. Materials and Methods: Two-institution retrospective analysis of whole-gland TULSA for men with grade group 1 and 2 prostate cancer. One institution placed SPT at the time of TULSA with clamp trials (day 10) and removal once voiding. The second placed UC until void trial (day 7). Outcomes included the International Prostate Symptom Score (IPSS), urinary bother score, catheter reinsertion, stricture, clean intermittent catheterization (CIC), and incontinence. Results: Forty-five patients (median age 67) were analyzed. The UC cohort ( N = 26) was older ( p = 0.007) than the SPT cohort ( N = 19) but with similar baseline prostate volumes, IPSS, and urinary bother scores. Patients receiving UC had fewer days with catheter ( p = 0.013). Although UC patients suffered more lower urinary tract symptoms at 1-month post-TULSA, there was no significant difference between IPSS scores at baseline and 6 months after surgery regardless of urinary management strategy, although the UC group noted significantly decreased urinary bother. Rates of infection were similar between groups. Six strictures were observed overall, with more in the SPT group, although the difference was not significant (4/19 [21.1%] SPT; 2/26 [7.7%] UC). At 6 months, incontinence rates were low and similar between groups (2/19 [10.5%] SPT; 4/26 [15.4%] UC) and only one patient (UC) required CIC. Conclusions: Our overall findings suggest that SPT and UC are both acceptable options for postoperative bladder drainage after whole-gland TULSA, with statistically similar rates of urinary complications but a slightly different side effect profile.
Analysis of Fixed and Variable Operating Room (OR) Time Point Efficiency in Partial Nephrectomies: Open Versus Robotic-assisted
Geldmaker, Laura , Hasse, Christopher H., Baird, Bryce , Ericson, Christian , Haehn, Daniela A. , Anyane-Yeboah, Abena N., Wieczorek, Mikolaj A. , Ball, Colleen T. , Pak, Raymond W., Thiel, David D. , Myers, Amanda A. , Lyon, Timothy D.

No container title available | April 25, 2022 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-1577467/v1 Get It

Abstract Objective: To analyze operating room (OR) efficiency by evaluating fixed and variable OR times for open (OPN) and robotic-assisted partial nephrectomies (RAPN).Methods: We analyzed consecutive OPN and RAPN performed by one surgeon over a 24-month period. All patients were placed in the lateral decubitus position and secured with a beanbag regardless of approach. Fixed (nonprocedural) OR times were prospectively collected and defined as: in room to anesthesia release time (IRAT), anesthesia release to cut time (ARCT), and close to wheels out time (CTWO). Variable OR time was procedural cut to close time (CTCT). Comparison of fixed and variable OR time points between OPN and RAPN were performed using the Wilcoxon rank sum test. Results: 146 RAPN and 31 OPN were evaluated from 2019-2020. Median IRAT was similar for RAPN versus OPN [20 min (IQR: 16-25) vs. 20 min (IQR: 16-26), P=0.57]. Median ARCT was longer for RAPN than it was for OPN [40 min (IQR: 36-46) vs. 34 min (IQR: 30-39), P<0.001]. Median CTWO was similar for OPN (12 min, IQR: 9-14) and RAPN (11 min, IQR: 7-15) (P=0.89). Median CTCT was longer for RAPN (202 min, IQR: 170-236) compared to OPN (164 min, IQR: 154-184) (P<0.001).Conclusions: In a single surgeon partial nephrectomy series with the same patient positioning, utilization of robotic technology was associated with longer surgeon operating time as well as less efficient fixed OR times, specifically ARCT.
Independent external validation of a nomogram to define risk categories for a significant decline in estimated glomerular filtration rate after robotic‐assisted partial nephrectomy
Bajalia, Essa M. , Myers, Amanda A. , Haehn, Daniela A. , Kahn, Amanda E. , Ball, Colleen T. , Thiel, David D. , Myers, Amanda , Kahn, Amanda

International Journal of Urology | November 2, 2020 | Volume: 28 | Issue: 1 | Pages: 75-79

10.1111/iju.14404 Get It

ObjectiveTo validate the Martini nomogram predicting the decline in estimated glomerular filtration rate after robotic‐assisted partial nephrectomy.MethodsEstimated glomerular filtration rate of 406 patients from a single surgeon series was calculated before robotic‐assisted partial nephrectomy and at postoperative intervals. To determine the risk group, we calculated the total score and corresponding risk of significant estimated glomerular filtration rate reduction at 15 months using the Martini nomogram. The primary outcome was a reduction in estimated glomerular filtration rate of ≥25% from preoperative levels between 1 and 12 months after surgery.ResultsThe median length of follow up for this study was 12 months (interquartile range 6–12 months). Overall, 134 (33%) patients were in the low‐, 143 (35%) in the intermediate‐, 119 (29%) in the high‐ and 10 (2%) in the very high‐risk groups. The Kaplan–Meier estimates for the probability of significant estimated glomerular filtration rate reduction by 12 months after robotic‐assisted partial nephrectomy was 12.9% in the low‐risk group, 24.0% in the intermediate‐risk group, 49.7% in the high‐risk group and 40.0% in the very high‐risk group. Harrell’s C‐index for discriminating between those with and without a significant reduction in estimated glomerular filtration rate 1–12 months after robotic‐assisted partial nephrectomy was 0.73 (95% confidence interval 0.68–0.78).ConclusionsThe risk groups proposed by the Martini nomogram are accurate in predicting those at higher risk for a >25% decline in postoperative estimated glomerular filtration rate after robotic‐assisted partial nephrectomy at 12 months.
Laparoscopic Completion Nephrectomy for Local Surgical Bed Recurrence After Partial Nephrectomy: An Analysis of Procedural Complexity and Feasibility
Shah, Paras , Patel, Vinay , Kozel, Zachary , Vira, Manish , Myers, Amanda A. , Kaplan-Marans, Elie , Yaskiv, Oksana, Kavoussi, Louis R., Richstone, Lee, Myers, Amanda

Journal of Endourology | November 6, 2018 | Volume: 32 | Issue: 12 | Pages: 1114-1119

10.1089/end.2018.0384 Get It