Papers by Devon Snow-Lisy
Current Bladder Dysfunction Reports
The Journal of Urology
INTRODUCTION AND OBJECTIVES: Endoscopic injection of a bulking agent is a common first-line appro... more INTRODUCTION AND OBJECTIVES: Endoscopic injection of a bulking agent is a common first-line approach to the treatment of vesicoureteral reflux (VUR). While early outcomes are comparable to open ureteroneocystotomy, 5-25% of children will eventually develop recurrent reflux necessitating repeat injections or open ureteral reimplantation. The objective of this study was to determine whether prior endoscopic injection of a bulking agent impacts outcomes of subsequent open ureteral reimplantation. METHODS: Using a retrospective cohort design, radiographic and clinical outcomes of open ureteral reimplantation were compared between patients with and without prior endoscopic correction of reflux. Surgical and hospitalization data were also compared between groups and a cost comparison was performed to assess differences in healthcare costs between the two cohorts. Units of analysis included total ureters or total patients. For certain variables, subanalysis of unilateral versus bilateral reimplantation was included. RESULTS: A total of 258 patients underwent open reimplantation for VUR between 2007-2016 by five pediatric urologists. Final analysis included 192 patients with preoperative and postoperative VCUG and follow-up data, with a total of 342 reimplanted ureters. There was no significant difference in rates of radiographic resolution among 317 reimplanted refluxing ureters with and without prior endoscopic treatment (96.3% vs. 96.2%, respectively, p¼0.981). No difference in clinical success rates was noted among the 192 patients (99.4% vs. 100%, p¼0.755). There were no statistically significant differences between duration of surgery or length of stay. There were no statistically significant differences between total charges, total costs, and OR costs between groups. CONCLUSIONS: This study indicates that prior endoscopic injection of a bulking agent does not impact the outcomes or costs of subsequent open ureteroneocystotomy. While prior studies have demonstrated tissue changes associated with injection of a bulking agent, these do not seem to significantly impact the difficulty of later open surgery or the success rates compared to patients who proceed directly to open correction of reflux. This study is, to the authors' knowledge, the first to analyze healthcare costs associated with salvage ureteroneocystotomy for VUR.
The Journal of Urology, 2017
Children with bladder dysfunction resulting in increased storage pressure are at risk for renal d... more Children with bladder dysfunction resulting in increased storage pressure are at risk for renal deterioration. The current gold standard for evaluation of bladder pressure is urodynamics, an invasive test requiring catheterization. We evaluated ultrasound shear wave elastography as a novel means of assessing bladder biomechanical properties associated with increased bladder pressure. Concurrent shear wave elastography and urodynamics were performed. Ultrasound shear wave elastography images were obtained of the anterior and posterior wall when empty and at 25%, 50%, 75% and 100% expected bladder capacity, and end fill volume. Regions of interest were confirmed by a pediatric radiologist. Bladder cohorts were defined as compliant (capacity detrusor pressure less than 25 cm H2O) and noncompliant (25 cm H2O or greater). Pearson correlation coefficients and a mixed effects model evaluated the relationship between shear wave speed and detrusor pressure, compliance and normalized compliance. An unpaired t-test was used for between cohort analyses. In all 23 subjects mean shear wave speed of the anterior and posterior bladder walls significantly correlated with detrusor pressure throughout filling. When comparing compliant and noncompliant bladders, mean shear wave speed and detrusor shear wave speed of the anterior wall significantly increased with filling of noncompliant bladders. Shear wave speed remained at baseline levels in compliant bladders. Mean shear wave speed of the anterior wall was significantly correlated with compliance and normalized compliance. Ultrasound shear wave elastography bladder measurements correlate well with bladder storage pressure, and shear wave speed measurements differ between compliant and noncompliant bladders. This is the first known study to demonstrate that shear wave elastography is promising as a bedside modality for the assessment of bladder dysfunction in children.
PloS one, 2015
Recent studies have demonstrated that mesenchymal stem cells (MSCs) combined with CD34+ hematopoi... more Recent studies have demonstrated that mesenchymal stem cells (MSCs) combined with CD34+ hematopoietic/stem progenitor cells (HSPCs) can function as surrogate urinary bladder cells to synergistically promote multi-faceted bladder tissue regeneration. However, the molecular pathways governing these events are unknown. The pleiotropic effects of Wnt5a and Cyr61 are known to affect aspects of hematopoiesis, angiogenesis, and muscle and nerve regeneration. Within this study, the effects of Cyr61 and Wnt5a on bladder tissue regeneration were evaluated by grafting scaffolds containing modified human bone marrow derived MSCs. These cell lines were engineered to independently over-express Wnt5a or Cyr61, or to exhibit reduced expression of Cyr61 within the context of a nude rat bladder augmentation model. At 4 weeks post-surgery, data demonstrated increased vessel number (~250 vs ~109 vessels/mm2) and bladder smooth muscle content (~42% vs ~36%) in Cyr61OX (over-expressing) vs Cyr61KD (knock...
The Journal of Urology, 2015
The Journal of Urology, 2015
The Journal of urology, Jan 18, 2015
Nanoparticles, submicroscopic particles typically ranging from 100-300 nm, are interesting for th... more Nanoparticles, submicroscopic particles typically ranging from 100-300 nm, are interesting for the potential treatment of testicular disorders because they can be engineered to allow delivery to privileged tissues such as across the blood-brain-barrier or, theoretically, the blood-testis-barrier. We compare the effects of anatomical and/or ligand targeting on testicular nanoparticle uptake in a rat model. Rats (n=48) were divided into six groups: control group, intra-arterial injection of unconjugated nanoparticles with and without saline flush, intravenous injection of unconjugated nanoparticles, intra-arterial injection of follicle stimulating hormone conjugated nanoparticles, intravenous injection of follicle stimulating hormone conjugated nanoparticles and intra-arterial injection of trans-activating transcriptor conjugated nanoparticles. A dose response curve was then assessed for intra-arterially injected unconjugated nanoparticles. Using high performance liquid chromatography...
The Journal of urology, Jan 31, 2015
Review the current literature regarding the current urologic management of spina bifida from pren... more Review the current literature regarding the current urologic management of spina bifida from prenatal diagnosis to adulthood. We searched MEDLINE, EMBASE and PubMed for English articles published through December 2014 using search terms "spina bifida", "spinal dysraphism" and "bladder". Based on review of titles and abstracts, 437 of 1869 articles were identified as addressing topics related to open spina bifida in pediatric patients or the long term or quality of life outcomes in adult patients with spina bifida. We summarize this literature to inform clinical guidelines and a framework for disease management. The birth prevalence of spina bifida in the United States has recently plateaued at approximately 30 per 100,000 births. With improved management, more patients are surviving to adulthood with an economic impact of $319,000 over the lifetime of one spina bifida patient. Recent advancements in prenatal surgery have demonstrated that prenatal closu...
Drug delivery and translational research, 2011
Nanotechnology has been increasingly utilized for the targeting and delivery of novel therapeutic... more Nanotechnology has been increasingly utilized for the targeting and delivery of novel therapeutic agents to different tissues and cell types. The current therapeutic options for testicular disorders fall short in many instances due to difficulty traversing the blood-testis barrier, systemic toxicities, and complicated dosing regiments. For testicular tissue, potential targeting can be obtained either via anatomic methods or specific ligands such as luteinizing hormone or follicle-stimulating hormone analogs. Potential novel therapeutic agents include DNA, RNA, cytokines, peptide receptor antagonists, peptide receptor agonists, hormones, and enzymes. Nanotherapeutic treatment of testicular cancer, infertility, testicular torsion, orchalgia, hypogonadism, testicular infections, and cryptorchidism within the framework of potential target cells are an emerging area of research. While there are many potential applications of nanotechnology in drug delivery to the testis, this remains a r...
Frontiers in Bioscience, 2013
Introduction 3. Logistics of a good diagnostic andrology laboratory 3.1. Certifications and accre... more Introduction 3. Logistics of a good diagnostic andrology laboratory 3.1. Certifications and accreditations 3.2. Quality control 3.3. Testing offered 4. Algorithm for evaluation of the infertile patient 5. Interpreting andrology laboratory tests 5.1.
Surgical Management of Urolithiasis, 2013
Journal of the National Comprehensive Cancer Network : JNCCN, 2010
Since the first introduction of prostate-specific antigen (PSA) as a screening tool in the 1980s,... more Since the first introduction of prostate-specific antigen (PSA) as a screening tool in the 1980s, the accurate diagnoses of clinically significant prostate cancer remains a challenge. Analysis of a correlation between PSA levels and prostate biopsies of men with PSA 3 ng/mL or less in the placebo group of the Prostate Cancer Prevention Trial suggested that no "normal" PSA level exists. With the acknowledgement that PSA level is considered a continuum rather than a dichotomous marker, accurately diagnosing clinically significant prostate cancer is even more challenging. Nomograms are increasingly being used as tools in the clinical setting to address this challenge. Through incorporating multiple clinical factors, such as PSA, digital rectal examination, age, race, prostate volume, family history, and previous negative biopsy, risk calculators can improve sensitivity of diagnosis over using a PSA cutoff alone. This article discusses the rational for the use of nomograms and...
Urology, 2012
A man interested in active surveillance of low-risk prostate cancer sought a second opinion after... more A man interested in active surveillance of low-risk prostate cancer sought a second opinion after having undergone an inappropriate metastatic evaluation that demonstrated multiple enhancing liver masses. Because of his history of splenectomy for trauma, hepatic splenosis was suspected. Despite reassurance, the patient desired biopsy of the masses to confirm splenosis. The imaging features and pathophysiology of hepatic splenosis are presented. Owing to the low rates of metastatic disease, the current guidelines do not recommend diagnostic imaging for low-risk prostate cancer. The present case illustrates the dangers of the current widespread practice of inappropriate diagnostic imaging of patients with low-risk prostate cancer. UROLOGY 79: e73-e74, 2012.
Urology, 2013
To address the challenges that today&... more To address the challenges that today's trainees encounter, such as information overload and reduced immersion in the field, and recognizing their preference for novel educational resources, an electronic case-based urology learning program was developed. Each case was designed to illustrate the basic principles of the disease process and the fundamentals of evaluation and management using the Socratic method, recapitulating a prototypical patient encounter. A 21-question survey was developed after review of published reports of classroom and clinical learning environment surveys. The target group was 2 pilot urology training programs (the Cleveland Clinic and University Hospitals-Case Medical Center). The responses were entirely anonymous. A total of 32 trainees participated (8 fellows and 24 residents), representing a 53% response rate. Most trainees (79%) were able to process cases within an average of ≤ 10 minutes. Of the trainees, 91% reported referring back to particular cases for patient care, to review for examinations, or for studying. Most trainees believed a case-based urology learning program would be a potentially important resource for clinical practice (69%) and for preparing for the in-service (63%) or board (69%) examinations. Most trainees believed the program met its goals of illustrating the basics principles of the disease process (88%), outlining the fundamentals of evaluation and management (94%), and improving the trainees' knowledge base (91%). An electronic case-based urology learning program is feasible and useful and stimulates learning at all trainee levels.
Urology, 2013
OBJECTIVE To compare perioperative outcomes of robot-assisted partial nephrectomy (RAPN) for hila... more OBJECTIVE To compare perioperative outcomes of robot-assisted partial nephrectomy (RAPN) for hilar vs nonhilar tumors. MATERIALS AND METHODS The study retrospectively reviewed 364 patients with available computed tomography scans undergoing RAPN. Demographic data and perioperative outcomes results were compared between the hilar (group 1, n ¼ 70) and nonhilar tumors (group 2, n ¼ 294). Multivariate analysis was used to identify predictors of warm ischemia time (WIT), estimated blood loss (EBL), major perioperative complications, and postoperative renal function. RESULTS There were no differences with respect to demographic variables. Hilar tumors had higher RENAL (radius, exophytic/endophytic properties of the tumor, nearness of tumor deepest portion to the collecting system or sinus, anterior/posterior descriptor and the location relative to polar lines) scores (P <.001) and were larger (3.9 vs 2.6 cm, P <.001). Surgeries for hilar tumors were associated with greater operative time (210 vs 180 minutes, P <.001), longer WIT (27 vs 17 minutes, P <.001), and increased EBL (250 vs 200 mL, P ¼ .04). No differences were noted in transfusion rate, length of stay, complications (overall and major) and positive margins. Postoperative estimated glomerular filtration rate showed no significant difference between hilar vs nonhilar patients on postoperative day 3 (70.12 vs 74.71 mL/min/1.73 m 2 , P ¼ .31) or at last follow-up (72.62 vs 75.78 mL/min/1.73 m 2 , P ¼ .40), respectively. Multivariate analysis found hilar location was independently associated with increased WIT without significant changes in EBL, major complications, or postoperative renal function. CONCLUSION RAPN represents a safe and effective procedure for hilar tumors. Hilar location for patients undergoing RAPN in a high-volume institution seems not be associated with an increased risk of transfusions, major complications, or decline of early postoperative renal function. UROLOGY 81:
Urology, 2009
A 65-year-old man underwent computed tomography (CT) of the abdomen during evaluation for anemia ... more A 65-year-old man underwent computed tomography (CT) of the abdomen during evaluation for anemia which showed a 10 cm right renal mass and inferior vena cava (IVC) thrombus. Positron emission tomography (PET)/CT revealed uptake of flurorodeoxyglucose (FDG) within only the tumor mass and thrombus. Right radical nephrectomy and IVC thrombectomy with IVC patch graft reconstruction were performed. Final pathology showed pT3bNxMx renal cell carcinoma (RCC) with IVC thrombus composed of poorly differentiated RCC. There is no evidence of recurrence at one year follow-up. We discuss the role of
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Papers by Devon Snow-Lisy