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1.
IEEE Open J Eng Med Biol ; 5: 133-139, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487093

RESUMEN

Goal: We present a new framework for in vivo image guidance evaluation and provide a case study on robotic partial nephrectomy. Methods: This framework (called the "bystander protocol") involves two surgeons, one who solely performs the therapeutic process without image guidance, and another who solely periodically collects data to evaluate image guidance. This isolates the evaluation from the therapy, so that in-development image guidance systems can be tested without risk of negatively impacting the standard of care. We provide a case study applying this protocol in clinical cases during robotic partial nephrectomy surgery. Results: The bystander protocol was performed successfully in 6 patient cases. We find average lesion centroid localization error with our IGS system to be 6.5 mm in vivo compared to our prior result of 3.0 mm in phantoms. Conclusions: The bystander protocol is a safe, effective method for testing in-development image guidance systems in human subjects.

2.
J Endourol ; 38(4): 395-407, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38251637

RESUMEN

Introduction: Three-dimensional image-guided surgical (3D-IGS) systems for minimally invasive partial nephrectomy (MIPN) can potentially improve the efficiency and accuracy of intraoperative anatomical localization and tumor resection. This review seeks to analyze the current state of research regarding 3D-IGS, including the evaluation of clinical outcomes, system functionality, and qualitative insights regarding 3D-IGS's impact on surgical procedures. Methods: We have systematically reviewed the clinical literature pertaining to 3D-IGS deployed for MIPN. For inclusion, studies must produce a patient-specific 3D anatomical model from two-dimensional imaging. Data extracted from the studies include clinical results, registration (alignment of the 3D model to the surgical scene) method used, limitations, and data types reported. A subset of studies was qualitatively analyzed through an inductive coding approach to identify major themes and subthemes across the studies. Results: Twenty-five studies were included in the review. Eight (32%) studies reported clinical results that point to 3D-IGS improving multiple surgical outcomes. Manual registration was the most utilized (48%). Soft tissue deformation was the most cited limitation among the included studies. Many studies reported qualitative statements regarding surgeon accuracy improvement, but quantitative surgeon accuracy data were not reported. During the qualitative analysis, six major themes emerged across the nine applicable studies. They are as follows: 3D-IGS is necessary, 3D-IGS improved surgical outcomes, researcher/surgeon confidence in 3D-IGS system, enhanced surgeon ability/accuracy, anatomical explanation for qualitative assessment, and claims without data or reference to support. Conclusions: Currently, clinical outcomes are the main source of quantitative data available to point to 3D-IGS's efficacy. However, the literature qualitatively suggests the benefit of accurate 3D-IGS for robotic partial nephrectomy.


Asunto(s)
Robótica , Cirugía Asistida por Computador , Humanos , Imagenología Tridimensional/métodos , Nefrectomía/métodos , Cirugía Asistida por Computador/métodos
3.
Robotica ; 41(5): 1590-1616, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37732333

RESUMEN

Robots and inertial measurement units (IMUs) are typically calibrated independently. IMUs are placed in purpose-built, expensive automated test rigs. Robot poses are typically measured using highly accurate (and thus expensive) tracking systems. In this paper, we present a quick, easy, and inexpensive new approach to calibrate both simultaneously, simply by attaching the IMU anywhere on the robot's end effector and moving the robot continuously through space. Our approach provides a fast and inexpensive alternative to both robot and IMU calibration, without any external measurement systems. We accomplish this using continuous-time batch estimation, providing statistically optimal solutions. Under Gaussian assumptions, we show that this becomes a nonlinear least squares problem and analyze the structure of the associated Jacobian. Our methods are validated both numerically and experimentally and compared to standard individual robot and IMU calibration methods.

4.
J Endourol ; 37(4): 453-461, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36585860

RESUMEN

Introduction/Background: There are increasing reports of serious complications related to the air pyelography technique, which raise concerns about the safety of room air (RA) injection into the renal collecting system. Carbon dioxide (CO2) is much more soluble in blood than nitrogen and oxygen and thus considerably less likely to cause gas emboli. Iodinated contrast medium (ICM) is expensive, and supplies may not be as reliable as previously assumed. CO2 pyelography (CO2-P) techniques using standard fluoroscopy and digital subtraction fluoroscopy (CO2 digital subtraction pyelography [CO2-DSP]) are described. Materials and Methods: During the endourologic stone cases, 15 to 20 mL of CO2 gas was typically injected into the renal pelvis through a catheter or sheath. Imaging was usually obtained with endovascular CO2 digital subtraction angiography settings using either a traditional fluoroscopy system (TFS) or robotic arm multiplanar fluoroscopy system (RMPFS) (Artis Zeego Care+Clear®; Siemens). Results: CO2-P was performed in 22 endoscopic stone treatment cases between March 2021 and August 2022, primarily using digital subtraction settings in 20 cases. CO2-DSP overall provided higher quality images of the renal pelvis and collecting system than CO2-P, but with a relatively higher radiation dose. Following a quality intervention, fluoroscopy doses for CO2-DSP cases were decreased by 81% overall. The use of CO2-P avoided fluoroscopic or intraoperative CT (ICT) artifacts seen with intraluminal ICM. Conclusions: CO2-P allows the urologist to obtain imaging of the renal collecting system without ICM and with much lower risk of air embolism compared with RA pyelography. CO2 is a nearly cost-free alternative to ICM. Because CO2 is widely available and the technique is easy to perform, we propose that CO2-P should be favored over traditional air pyelography to improve patient safety.


Asunto(s)
Dióxido de Carbono , Medios de Contraste , Urografía , Humanos , Medios de Contraste/efectos adversos , Endoscopía , Fluoroscopía
5.
Nat Commun ; 13(1): 6036, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36229464

RESUMEN

Cribriform prostate cancer, found in both invasive cribriform carcinoma (ICC) and intraductal carcinoma (IDC), is an aggressive histological subtype that is associated with progression to lethal disease. To delineate the molecular and cellular underpinnings of ICC/IDC aggressiveness, this study examines paired ICC/IDC and benign prostate surgical samples by single-cell RNA-sequencing, TCR sequencing, and histology. ICC/IDC cancer cells express genes associated with metastasis and targets with potential for therapeutic intervention. Pathway analyses and ligand/receptor status model cellular interactions among ICC/IDC and the tumor microenvironment (TME) including JAG1/NOTCH. The ICC/IDC TME is hallmarked by increased angiogenesis and immunosuppressive fibroblasts (CTHRC1+ASPN+FAP+ENG+) along with fewer T cells, elevated T cell dysfunction, and increased C1QB+TREM2+APOE+-M2 macrophages. These findings support that cancer cell intrinsic pathways and a complex immunosuppressive TME contribute to the aggressive phenotype of ICC/IDC. These data highlight potential therapeutic opportunities to restore immune signaling in patients with ICC/IDC that may afford better outcomes.


Asunto(s)
Carcinoma Intraductal no Infiltrante , Neoplasias de la Próstata , Apolipoproteínas E , Carcinoma Intraductal no Infiltrante/genética , Proteínas de la Matriz Extracelular , Humanos , Ligandos , Masculino , Clasificación del Tumor , Neoplasias de la Próstata/patología , ARN , Receptores de Antígenos de Linfocitos T , Análisis de la Célula Individual , Microambiente Tumoral/genética
6.
J Urol ; 208(1): 126-127, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35442764
7.
World J Urol ; 40(3): 671-677, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34132897

RESUMEN

Image-guidance during partial nephrectomy enables navigation within the operative field alongside a 3-dimensional roadmap of renal anatomy generated from patient-specific imaging. Once a process is performed by the human mind, the technology will allow standardization of the task for the benefit of all patients undergoing robot-assisted partial nephrectomy. Any surgeon will be able to visualize the kidney and key subsurface landmarks in real-time within a 3-dimensional simulation, with the goals of improving operative efficiency, decreasing surgical complications, and improving oncologic outcomes. For similar purposes, image-guidance has already been adopted as a standard of care in other surgical fields; we are now at the brink of this in urology. This review summarizes touch-based approaches to image-guidance during partial nephrectomy, as the technology begins to enter in vivo human evaluation. The processes of segmentation, localization, registration, and re-registration are all described with seamless integration into the da Vinci surgical system; this will facilitate clinical adoption sooner.


Asunto(s)
Neoplasias Renales , Procedimientos Quirúrgicos Robotizados , Robótica , Humanos , Riñón/cirugía , Neoplasias Renales/cirugía , Nefrectomía/métodos , Tacto
8.
J Cancer Res Ther ; 17(2): 420-425, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34121687

RESUMEN

OBJECTIVES: To investigate the relationship between gender, body mass index (BMI), and prognosis in renal cell carcinoma (RCC) patients. MATERIALS AND METHODS: We retrospectively reviewed 1353 patients with RCC who underwent a partial or radical nephrectomy between 1988 and 2015. The association among sex, BMI, stage, grade, overall survival (OS), and recurrence-free survival (RFS) was analyzed. RESULTS: The median age of the patients was 59.4 ± 11.9 years. Female patients had proportionally lower grade tumors than male patients (Grade I-II in 75.5% vs. 69.3% in women and men, respectively, P = 0.022). There was no relationship between Fuhrman grade and BMI when substratified by gender (p > 0.05). There was a nonsignificant trend toward more localized disease in female patients (p = 0.058). There was no relationship between T stage and BMI when stratified by gender (p > 0.05). Patients with higher BMI had significantly better OS (p = 0.0004 and P = 0.0003) and RFS (P = 0.0209 and P =0.0082) whether broken out by lower 33rd or 25th percentile. Male patients with higher BMI had significantly better OS and RFS rates. However, there was no relationship between BMI and OS or RFS for female patients (P > 0.05). Multivariate analysis of the entire cohort demonstrated that a BMI in the lower quartile independently predicts OS (hazard ratio 1.604 [95% confidence interval: 1.07-2.408], P = 0.022) but not RFS (P > 0.05). When stratified by gender, there was no relationship between BMI and either OS or RFS (P > 0.05). CONCLUSIONS: Increasing BMI was associated with RCC prognosis. However, the clinical association between BMI and oncologic outcomes may be different between men and women.


Asunto(s)
Índice de Masa Corporal , Carcinoma de Células Renales/mortalidad , Neoplasias Renales/mortalidad , Recurrencia Local de Neoplasia/epidemiología , Anciano , Carcinoma de Células Renales/cirugía , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Nefrectomía , Pronóstico , Estudios Retrospectivos , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Factores Sexuales
9.
IEEE Trans Med Robot Bionics ; 2(4): 578-581, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33251487

RESUMEN

Current surgical approaches to radical prostatectomy are associated with high rates of erectile dysfunction and incontinence. These complications occur secondary to the disruption of surrounding healthy tissue, which is required to expose the prostate. The urethra offers the least invasive access to the prostate, and feasibility has been demonstrated of enucleating the prostate with an endoscope using Holmium laser, which can itself be aimed by concentric tube robots. However, the transurethral approach to radical prostatectomy has thus far been limited by the lack of a suitable means to perform an anastomosis of the urethra to the bladder after prostate removal. Only a few intraluminal anastomotic devices currently exist, and none are small enough to pass through the urethra. In this paper we describe a new way to perform an anastomosis in the small luminal space of the urethra, harnessing the dexterity and customizability of concentric tube manipulators. We demonstrate a successful initial proof-of-concept anastomosis in an anthropomorphic phantom of the urethra and bladder.

10.
IEEE Trans Med Robot Bionics ; 2(2): 196-205, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-36176345

RESUMEN

Partial nephrectomy involves removing a tumor while sparing surrounding healthy kidney tissue. Compared to total kidney removal, partial nephrectomy improves outcomes for patients but is underutilized because it is challenging to accomplish minimally invasively, requiring accurate spatial awareness of unseen subsurface anatomy. Image guidance can enhance spatial awareness by displaying a 3D model of anatomical relationships derived from medical imaging information. It has been qualitatively suggested that the da Vinci robot is well suited to facilitate image guidance through touch-based registration. In this paper we validate and advance this concept toward real-world use in several important ways. First, we contribute the first quantitative accuracy evaluation of touch-based registration with the da Vinci. Next, we demonstrate real-time touch-based registration and display of medical images for the first time. Lastly, we perform the first experiments validating use of touch-based image guidance to improve a surgeon's ability to localize subsurface anatomical features in a geometrically realistic phantom.

11.
IEEE ASME Trans Mechatron ; 25(3): 1432-1443, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33746503

RESUMEN

Open surgical approaches are still often employed in neurosurgery, despite the availability of neuroendoscopic approaches that reduce invasiveness. The challenge of maneuvering instruments at the tip of the endoscope makes neuroendoscopy demanding for the physician. The only way to aim tools passed through endoscope ports is to tilt the entire endoscope; but, tilting compresses brain tissue through which the endoscope passes and can damage it. Concentric tube robots can provide necessary dexterity without endoscope tilting, while passing through existing ports in the endoscope and carrying surgical tools in their inner lumen. In this paper we describe the mechatronic design of a new concentric tube robot that can deploy two concentric tube manipulators through a standard neuroendoscope. The robot uses a compact differential drive and features embedded motor control electronics and redundant position sensors for safety. In addition to the mechatronic design of this system, this paper contributes experimental validation in the context of colloid cyst removal, comparing our new robotic system to standard manual endoscopy in a brain phantom. The robotic approach essentially eliminated endoscope tilt during the procedure (17.09° for the manual approach vs. 1.16° for the robotic system). The robotic system also enables a single surgeon to perform the procedure - typically in a manual approach one surgeon aims the endoscope and another operates the tools delivered through its ports.

12.
Ann Biomed Eng ; 48(1): 181-191, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31342337

RESUMEN

New robotic systems have recently emerged to assist with peripheral lung access, but a robotic system for rigid bronchoscopy has yet to be developed. We describe a new robotic system that can deliver thin robotic manipulators through the ports of standard rigid bronchoscopes. The manipulators bend and elongate to provide maneuverability of surgical tools at the endoscope tip, without endoscope motion. We describe an initial feasibility study on the use of this system to bronchoscopically treat a central airway obstruction (CAO). CAO is prevalent and can be life-threatening in patients with large tumors, and conventional rigid bronchoscopic treatments place patients at risk of complications including broken teeth, neck trauma and damage to oropharyngeal structures due to significant forces induced by bronchoscope tilting and manipulation. In this study, we used an ex vivo ovine airway model to demonstrate the ability of a physician using the robotic system to efficiently remove tissue and restore the airway. Pre- and post-operative CT scans showed that the robot was able to reduce the degree of airway obstruction stenosis from 75 to 14% on average for five CAO resections performed in an ex vivo animal model. Using cadaver experiments, we demonstrated the potential of the robotic system to substantially reduce the intraoperative forces applied to the patient's head and neck (from 80.6 to 4.1 N). These preliminary results illustrate that CAO removal is feasible with our new rigid bronchoscopy robot system, and that this approach has the potential to reduce forces applied to the patient due to bronchoscope angulation, and thereby reduce the risk of complications encountered during CAO surgery.


Asunto(s)
Obstrucción de las Vías Aéreas/cirugía , Broncoscopía/instrumentación , Robótica , Animales , Cadáver , Estudios de Factibilidad , Ovinos
13.
IEEE Trans Biomed Eng ; 66(11): 3176-3184, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30835205

RESUMEN

OBJECTIVE: This paper describes a surgical device that provides both wrist and elbow dexterity without motors or electronics. The device provides dexterity advantages in minimally invasive surgery typically associated with robotic systems, but does so with many fewer components. Fully mechanical designs of this type promise to deliver "robot-like dexterity" at a lower financial cost than current surgical robotic systems. METHODS: Most non-robotic articulated surgical tools developed to date feature one or two degrees-of-freedom (DOF) close to the tool tip (i.e., a "wrist"). In this paper, we describe a new tool that not only features a two-DOF wrist, but also augments its dexterity with a two-DOF "elbow" consisting of a multi-backbone design seen previously only in robotic systems. Such an elbow offers high stiffness in a thin form factor. This elbow requires static balancing, which we accomplish with springs in the handle, so that the surgeon can benefit from the stiffness without feeling it while using the device. RESULTS: We report the overall tool design and experiments evaluating how well our static balance mechanism compensates for the multi-backbone elbow's intrinsic stiffness. CONCLUSION: We demonstrate the use of a multi-backbone elbow in a manual tool for the first time and show how to combine the elbow with a pin joint wrist in a fully mechanical (i.e., non-robotic) tool. SIGNIFICANCE: This paper is a step toward high dexterity, low-cost surgical instruments that bring some benefits of surgical robotic systems to patients and surgeons at a lower cost.


Asunto(s)
Procedimientos Quirúrgicos Robotizados/instrumentación , Instrumentos Quirúrgicos , Diseño de Equipo , Humanos , Fenómenos Mecánicos , Procedimientos Quirúrgicos Robotizados/economía
14.
J Endourol ; 33(6): 480-485, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30618280

RESUMEN

Objective: Kidney stone formers are at risk for opioid dependence. The aim of this study is to describe opiate exposure and determine predictors of prolonged opiate use among kidney stone formers after surgery. Materials and Methods: A retrospective review was performed among patients who underwent ureteroscopy for upper tract stone disease. Prescription data were ascertained from a statewide prescribing database. Demographic data and surgical factors were collected from the electronic medical record. Predictors of additional postsurgery prescriptions filled within 30 days and persistent opiate use 60 days after ureteroscopy were determined. Results: Among 208 patients, 127 (61%) had received preoperative opiate prescriptions within 30 days before surgery. Overall, 12% (n = 25) of patients required an additional opiate prescription within 30 days after ureteroscopy, and 7% (n = 14) of patients continued to use opiate medications more than 60 days postoperatively. Patients continuing to use opiates long-term were not chronic opiate users. For both outcomes, preoperative opiate exposure, including number of prescriptions, days prescribed, and unique providers had significant associations (all p < 0.05). Additionally, younger age (p = 0.049) was associated with obtaining an additional opiate prescription within 30 days. Lower BMI (p = 0.02) and higher ASA score (p = 0.03) were predictors of continued opiate use more than 60 days after ureteroscopy. Conclusions: The majority of stone formers have had opiate exposure before surgery, often from multiple providers. Approximately 1 in 8 stone formers who undergo ureteroscopy require additional opiate prescriptions within 30 days. A small but significant population receive opiates beyond the immediate postoperative period.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Cálculos Renales/complicaciones , Cálculos Renales/cirugía , Trastornos Relacionados con Opioides/prevención & control , Ureteroscopía , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Periodo Posoperatorio , Estudios Retrospectivos , Riesgo , Tennessee
15.
Urolithiasis ; 47(4): 395-400, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30349974

RESUMEN

Patients presenting acutely with obstructing stones often have a ureteral stent placed as a temporizing solution. Ureteroscopy is then commonly performed in a staged fashion, but occasionally the stone is found to have passed. We aimed to identify the frequency and predictors of ureteral stone passage with a stent in place. Records were reviewed to identify patients who had a stent placed for a single ureteral stone. Subsequent ureteroscopy or CT scan was used to ascertain stone passage. Effect of age, gender, BMI, stone diameter, alpha blocker use, urinary tract infection, hydronephrosis, and stent duration on stone passage was assessed. Inclusion and exclusion criteria were met in 209 patients. Mean maximum stone diameter was 6.5 ± 2.5 mm. Passage rates for stones < 3 mm, 3-4.9 mm, 5-6.9 mm, and ≥ 7 mm were 50%, 13%, 10%, and 0%, respectively. The overall rate of passage was 8%. Stone passage was associated with smaller maximum stone diameter, more distal stone location, and longer duration of stent before ureteroscopy/CT on univariate analysis (p < 0.01). Stone diameter and stent duration remained significantly associated on multivariable analysis (p = 0.001 and p = 0.05, respectively). Our findings suggest ureteral stone passage with a concurrent ureteral stent is not a rare event as it occurred in 14% of stones less then 7 mm in maximum diameter. Stone size and duration of stent before ureteroscopy or CT were found to be independent predictors of passage. Select patients with small ureteral stones who have been stented should be considered for a trial of urine straining or repeat imaging before subsequent ureteroscopy.


Asunto(s)
Catéteres de Permanencia , Stents , Cálculos Ureterales/terapia , Obstrucción Ureteral/terapia , Catéteres Urinarios , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Uréter/diagnóstico por imagen , Uréter/cirugía , Cálculos Ureterales/complicaciones , Cálculos Ureterales/diagnóstico por imagen , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/etiología , Ureteroscopía , Adulto Joven
16.
Urology ; 123: 64-69, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30195012

RESUMEN

OBJECTIVE: To compare outcomes of patients undergoing single session bilateral ureteroscopy (SSBU) to those undergoing planned staged ureteroscopy (URS) for bilateral nephrolithiasis. While SSBU has the advantage of 1 anesthetic procedure, some may pursue a staged approach due to the potential higher risk of complications and patient discomfort with 2 ureteral stents. METHODS: We retrospectively identified patients undergoing SSBU and planned staged URS for nephrolithiasis between December 2007 and December 2014. Preoperative characteristics, intraoperative techniques, and postoperative outcomes were compared. Stone burden was calculated as cumulative stone diameter. Residual stone fragments were defined as any stone visible on postoperative imaging. RESULTS: Sixty-three patients underwent SSBU and 37 underwent planned staged URS. Both cohorts had a relatively large cumulative stone burden (30.9 mm vs 32.4 mm, P = .71). Total operative time was significantly longer for planned staged URS (139 vs 86 minutes, P <.0001). There were no significant differences in complications or emergency room visits between the 2 cohorts despite bilateral ureteral stents being placed in the majority of the SSBU cohort (73%). There were no differences in stone-free rates or the need for additional procedures. CONCLUSION: SSBU is safe and effective with overall shorter operative times and similar stone-free rates compared to planned staged URS. Bilateral ureteral stent placement did not increase the rate of unplanned emergency visits. For patients with bilateral nephrolithiasis, urologists should strongly consider SSBU to limit anesthetic exposure, overall operative time, and health care costs.


Asunto(s)
Nefrolitiasis/cirugía , Ureteroscopía/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nefrolitiasis/patología , Estudios Retrospectivos , Resultado del Tratamiento , Ureteroscopía/efectos adversos
17.
Urology ; 125: 46-49, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30528717

RESUMEN

OBJECTIVE: To estimate effective dose of kidney-ureter-bladder (KUB) radiographs in a contemporary population of patients with urolithiasis. METHODS: A retrospective review was performed to identify patients visiting a urology clinic for urolithiasis where a KUB was obtained and whom had a recent computed tomography (CT). Effective dose for KUBs was estimated using a Monte Carlo based simulation program and for CT utilizing the reported dose-length-product. Age, gender, body mass index, and abdominal diameter were analyzed for association with effective dose. KUBs performed at outside facilities in referred patient were compared to those obtained locally when available. RESULTS: Fifty-four patients were identified meeting criteria. The majority (92.6%) of KUBs contained multiple radiographs. Mean effective dose was 2.15 mSv ± 1.67 mSv. Only 26% of examinations effective dose was under 1 mSv. Body mass index, abdominal thickness, and image count were all associated with an increase in dose (P < .01 each). Similar to local KUBs, 88% of outside examinations contained multiple images. CONCLUSION: KUB examinations in this contemporary setting are associated with a 2-fold higher effective dose then is often referenced. Increased effective dose is associated with increased patient size and number of images acquired. Nearly 1 in 5 patient's KUB effective dose was similar to a low-dose CT. KUBs role should be re-examined given its limited sensitivity, specificity, associated radiation, and other available imaging options.


Asunto(s)
Riñón/diagnóstico por imagen , Dosis de Radiación , Exposición a la Radiación/estadística & datos numéricos , Tomografía Computarizada por Rayos X , Uréter/diagnóstico por imagen , Vejiga Urinaria/diagnóstico por imagen , Urolitiasis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
18.
Urol Pract ; 4(5): 405-411, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29250578

RESUMEN

INTRODUCTION: Symptomatic urinary tract infection (UTI) is a known complication of cystoscopy with ureteral stent removal. However, little is known about the incidence and risk factors for post-cystoscopy UTI in renal transplant recipients, who likely represent a high-risk cohort. Our aim was to determine the infection rate following cystoscopy with stent removal in this population and identify opportunities for care improvement. METHODS: We performed a retrospective cohort study of office cystoscopies with stent removal in renal transplant recipients performed at a single institution from April 2012 through May 2014. Strict criteria were used to determine presence of symptomatic UTI within one month of the procedure. Fisher's exact tests were completed to examine associations between patient characteristics and post-transplant outcomes with UTI. RESULTS: A total of 324 patients were included. Mean age was 50.0 (SD 13.1) years, and 187 (57.7%) patients were male. Within this group,165 (52.5%) patients received a pre-procedural oral fluoroquinolone antibiotic dose prior to the procedure. Nine patients had symptomatic UTIs (2.8%), of which three infections (33.3%) were due to quinolone-resistant organisms. Female sex (P =0.04), but no other patient or post-operative characteristic was associated with symptomatic UTI, including the use of peri-procedural antibiotics. CONCLUSIONS: The incidence of symptomatic UTI after cystoscopy with ureteral stent removal in renal transplant recipients is less than three percent and comparable to post-cystoscopy UTI risk in the general population. Female sex is associated with symptomatic UTI. Further investigation is needed to identify groups most at risk for UTI and other complications.

19.
J Endourol ; 31(6): 573-576, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28264591

RESUMEN

INTRODUCTION: During ureteroscopy (URS), ureteral dilation may be required to increase the likelihood of accessing the ureter to complete the procedure. Thus, we sought to assess the safety and efficacy of using Lubriglide sequential ureteral dilators® (Boston Scientific) to promote primary URS, without need for prestenting. PATIENTS AND METHODS: Retrospective review was performed of a consecutive series of patients undergoing primary URS by a single surgeon (N.L.M.) from 2011 to 2013. The primary outcomes were to characterize the use, safety, and efficacy of sequential ureteral dilators to promote stone treatment during URS. RESULTS: A total of 316 nonprestented cases of primary URS were attempted over the study period. Use of sequential ureteral dilators to promote ureteral access was performed in 109 (34.5%) cases and was effective to allow completion of the procedure in 102 (93.6%) cases. No intraoperative complications occurred while performing sequential ureteral dilation. Fourteen patients (4.3%) required ureteral stent placement for passive ureteral dilation, with definitive stone treatment at a later date. Postoperative radiographic follow-up was available for 272 (86.1%) cases, and no ureteral strictures were detected in the ureteral dilation group. On multivariate analysis, both a history of prior extracorporeal shockwave lithotripsy [odds ratio (OR) 0.45, confidence interval (CI) 0.25, 0.81, p = 0.008] and prior URS (OR 0.42, CI 0.25, 0.70, p = 0.001) were inversely associated with need to perform ureteral dilation. CONCLUSIONS: Approximately 1/3 of nonprestented patients may require ureteral dilation for effective completion of primary URS. Use of sequential ureteral dilators may significantly decrease the need for prestenting and a secondary procedure to complete stone treatment. Thus, we conclude that sequential ureteral dilators represent a safe and effective method to perform ureteral dilation to promote ureteral access and allow for effective stone treatment in one setting.


Asunto(s)
Uréter/patología , Cálculos Ureterales/cirugía , Ureteroscopía/instrumentación , Adulto , Constricción Patológica , Dilatación/instrumentación , Dilatación/métodos , Femenino , Humanos , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Ureteroscopía/métodos
20.
J Endourol ; 31(3): 217-222, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27936931

RESUMEN

PURPOSE: Urinary diversion and augmentation cystoplasty are associated with long-term complications, including metabolic derangements, infectious complications, and urolithiasis. The aim of this series was to characterize upper and lower urinary tract (LUT) calculi in this population. METHODS: A retrospective chart review was performed on all patients with a history of urinary diversion or augmentation cystoplasty who subsequently underwent treatment for urolithiasis between January 1998 and May 2015. Data collected included demographics, perioperative characteristics, type of reconstructive procedure, urine culture, stone analysis, and metabolic evaluation. A statistical analysis was performed. RESULTS: Ninety-nine patients were identified with a history of urolithiasis and incontinent urinary diversion (28), neobladder (21), continent cutaneous diversion (12), and augmentation cystoplasty (38). LUT stones were more common than upper tract stones in all except for incontinent diversions, which only had one lower tract stone (p = 0.0001). Twenty-three percent of stones were metabolic. Several metabolic derangements were noted, including hypocitraturia (100%), elevated urine pH (100%), low urine volume (70%), and hyperoxaluria (35%). There was a 44% rate of recurrent urolithiasis. CONCLUSIONS: Given the high rate of stone recurrence among patients with a history of urinary diversion and augmentation cystoplasty, all measures should be taken to prevent recurrent stones. In addition to actions aimed to prevent infectious stones such as bladder and pouch irrigation, we recommend these patients undergo a full metabolic workup with targeted dietary changes and medical therapies.


Asunto(s)
Cistotomía/efectos adversos , Intestinos/trasplante , Procedimientos de Cirugía Plástica/efectos adversos , Complicaciones Posoperatorias/epidemiología , Cálculos Urinarios/epidemiología , Derivación Urinaria/efectos adversos , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Cálculos Urinarios/etiología , Adulto Joven
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