The introduction of the Ho:YAG laser 3 decades ago revolutionized the endoscopic treatment of urolithiasis. Since then, a variety of innovations have continued to evolve these devices, including the ...development of high-power lasers capable of high-frequency lithotripsy. The clinical utility of high-frequency lithotripsy, however, has not necessarily lived up to the potential suggested by in vitro studies. A review of the relevant literature, confirming strong similarities between the outcomes associated with high and lower power laser lithotripsy, follows.
We sought to compare the clinical effectiveness of the pulse-modulated Ho:YAG (holmium:yttrium-aluminum-garnet) laser and the thulium laser fiber for ureteroscopic stone management in a randomized ...clinical trial. The primary outcome was the ureteroscope time required to adequately fragment stones to 1 mm or less. Secondary outcomes were stone-free rate, complications, subjective surgeon measurement of laser performance, patient related stone quality of life outcomes, and measurements of laser efficiency.
An Institutional Review Board-approved randomized clinical trial was conducted to randomize patients to outpatient treatment with either the Moses 2.0 or thulium laser fiber in a 1:1 manner after stratification into groups based on the maximal diameter of treated stone (3-9.9 mm or 10-20 mm). Patient, stone, and operative parameters were compared using the appropriate categorical/continuous and parametric/nonparametric statistical tests (SPSS 25).
From July 16, 2021 to March 11, 2022, 108 patients were randomized and had primary endpoint data available for analysis; 52 patients were randomized to Ho:YAG and 56 patients to thulium laser fiber. Groups were well balanced with no significant differences observed for patient or stone characteristics. Ureteroscope time was not significantly different between modalities (Ho:YAG mean 21.4 minutes vs thulium laser fiber mean 19.9 minutes,
= .60), or within subgroup analysis by stone size, median Hounsfield units, or stone location. There were no significant differences observed in the stone-free rate and complications rate between the 2 lasers.
This randomized clinical trial suggests no significant clinical advantage of one laser technology over the other. Surgeon and institutional preference are the best approach when selecting one or the other.
Purpose of Review
Radiological imaging techniques and applications are constantly advancing. This review will examine modern imaging techniques in the diagnosis of urolithiasis and applications for ...surgical planning.
Recent Findings
The diagnosis of urolithiasis may be done via plain film X-ray, ultrasound (US), or contrast tomography (CT) scan. US should be applied in the workup of flank pain in emergency rooms and may reduce unnecessary radiation exposure. Low dose and ultra-low-dose CT remain the diagnostic standard for most populations but remain underutilized. Single and dual-energy CT provide three-dimensional imaging that can predict stone-specific parameters that help clinicians predict stone passage likelihood, identify ideal management techniques, and possibly reduce complications. Machine learning has been increasingly applied to 3-D imaging to support clinicians in these prognostications and treatment selection.
Summary
The diagnosis and management of urolithiasis are increasingly personalized. Patient and stone characteristics will support clinicians in treatment decision, surgical planning, and counseling.
We analyzed the impact of residual stone fragments seen on abdominal x-ray after ureteroscopy and laser lithotripsy on the risk of repeat surgical intervention.
Our study included 781 patients (802 ...renal units) who underwent ureteroscopy and laser lithotripsy with abdominal x-ray within 3 months postoperatively and who had at least 1 year of followup. Ureteroscopy and laser lithotripsy were performed using the dusting technique. We analyzed the association between surgical recurrence-free survival and the size of the largest residual fragment.
During a median followup of 4.2 years repeat surgery was performed on 161 renal units (20%). Of the repeat interventions 75% were done for symptomatic nephrolithiasis. Postoperative imaging showed residual stone fragments in 42% of cases. In the entire group the risk of repeat surgery was increased in renal units with residual fragments greater than 2 mm. The effect of the size of residual fragments on the risk of surgical recurrence varied by patient body mass index. It was much larger in nonobese subjects, who were at increased risk for repeat surgery with residual fragments of any size. In the obese subgroup only fragments greater than 2 mm increased the risk of surgical recurrence.
The association between the size of residual stone fragments detected by abdominal x-ray after ureteroscopy and laser lithotripsy, and the risk of repeat surgical intervention depends on patient body mass index. Nonobese patients with residual stone fragments of any size are at increased risk for repeat intervention compared to those with a negative abdominal x-ray. The predictive value of abdominal x-ray after ureteroscopy and laser lithotripsy is limited in obese patients.
Abstract Background Long-term comparative outcomes for radiofrequency ablation (RFA) versus partial nephrectomy (PN) for the primary treatment of clinical T1a renal cell carcinoma (RCC) have not ...previously been reported. Objective Report comparative 5-yr oncologic outcomes for RFA versus PN in patients with clinical T1a RCC. Design, setting, and participants Observational single-institution cohort study, involving consecutive patients with a solitary histologically confirmed T1a RCC treated by RFA or PN and followed for a minimum of 5 yr. Those presenting with synchronous multiple, metachronous, bilateral, and/or metastatic disease, a history of hereditary RCC syndromes, a family history of RCC, and with post-treatment follow-up <5 yr were excluded from analysis. Measurements The Kaplan-Meier method was used to determine 5-yr overall survival (OS), cancer-specific survival (CSS), local recurrence-free survival (local RFS), overall disease-free survival (DFS), and metastasis-free survival (MFS) for RFA versus PN. Survival curves were compared using the log-rank test. A p value ≤0.05 was considered statistically significant. Results and limitations A total of 37 patients in each group met the selection criteria. The RFA cohort was significantly older and had more advanced comorbidities, but other patient characteristics were similar. For RFA versus PN, median follow-up was 6.5 yr (interquartile range IQR: 5.8–7.1) versus 6.1 yr (IQR: 5.4–7.3) ( p = 0.68), respectively. The 5-yr OS was 97.2% versus 100% ( p = 0.31), CSS was 97.2% versus 100% ( p = 0.31), DFS was 89.2% versus 89.2% ( p = 0.78), local RFS was 91.7% versus 94.6% ( p = 0.96), and MFS was 97.2% versus 91.8% ( p = 0.35), respectively. Study limitations are retrospective data analysis, loss to follow-up, limited statistical power, and limited generalizability of our data. Conclusions In appropriately selected patients, RFA is an effective minimally invasive therapy for the treatment of cT1a RCC, yielding comparable long-term oncologic outcomes to nephron-sparing surgery.
Purpose Renal tumor size influences the efficacy of radio frequency ablation but identification of confident size cutoffs has been limited by small numbers and short followup. We evaluated tumor size ...related outcomes after radio frequency ablation for patients with adequate (greater than 3 years) followup. Materials and Methods We identified 159 tumors treated with radio frequency ablation as primary treatment. Disease-free survival was defined as the time from definitive treatment to local recurrence, detection of metastasis or the most recent imaging showing no evidence of disease. Patients were evaluated with contrast enhancing imaging preoperatively, and at 6 weeks, 6 months and at least annually thereafter. Results Median tumor size was 2.4 cm (range 0.9 to 5.4) with a median followup of 54 months (range 1.5 to 120). Renal cell carcinoma was confirmed in 72% of the 150 tumors that had pre-ablation biopsy (94%). The 3 and 5-year disease-free survival was comparable at 92% and 91% overall, and was dependent on tumor size, being 96% and 95% for tumors smaller than 3.0 cm and 79% and 79%, respectively, for tumors 3 cm or larger (p = 0.001). Most failures (14 of 18) were local, either incomplete ablations or local recurrences. This is an intent to treat analysis and, therefore, includes patients ultimately found to have benign tumors, although outcomes were comparable in patients with cancer. Conclusions Radio frequency ablation treatment success of the small renal mass is strongly correlated with tumor size. Radio frequency ablation provides excellent and durable outcomes, particularly in tumors smaller than 3 cm. Of tumors 3 cm or larger, approximately 20% will recur such that alternative treatment techniques should be considered. However, most treatment failures are local and are often successfully treated with another ablation session.
The traditional pathologic grading for human renal cell carcinoma (RCC) has low concordance between biopsy and surgical specimen. There is a need to investigate adjunctive pathology technique that ...does not rely on the nuclear morphology that defines the traditional grading. Changes in collagen organization in the extracellular matrix have been linked to prognosis or grade in breast, ovarian, and pancreatic cancers, but collagen organization has never been correlated with RCC grade. In this study, we used Second Harmonic Generation (SHG) based imaging to quantify possible differences in collagen organization between high and low grades of human RCC.
A tissue microarray (TMA) was constructed from RCC tumor specimens. Each TMA core represents an individual patient. A 5 μm section from the TMA tissue was stained with standard hematoxylin and eosin (H&E). Bright field images of the H&E stained TMA were used to annotate representative RCC regions. In this study, 70 grade 1 cores and 51 grade 4 cores were imaged on a custom-built forward SHG microscope, and images were analyzed using established software tools to automatically extract and quantify collagen fibers for alignment and density assessment. A linear mixed-effects model with random intercepts to account for the within-patient correlation was created to compare grade 1 vs. grade 4 measurements and the statistical tests were two-sided.
Both collagen density and alignment differed significantly between RCC grade 1 and RCC grade 4. Specifically, collagen fiber density was greater in grade 4 than in grade 1 RCC (p < 0.001). Collagen fibers were also more aligned in grade 4 compared to grade 1 (p < 0.001).
Collagen density and alignment were shown to be significantly higher in RCC grade 4 vs. grade 1. This technique of biopsy sampling by SHG could complement classical tumor grading approaches. Furthermore it might allow biopsies to be more clinically relevant by informing diagnostics. Future studies are required to investigate the functional role of collagen organization in RCC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We examined the history of the Endourological Society through the lens of its fellowship programs in the United States (U.S.).
A review of the list of fellowship programs published annually in the
...from 1987 to 2015 allowed us to track the growth in fellowship programs over time. We reviewed the Endourological Society fellowship database and the websites for each of the fellowship programs for the names of graduates from each program. A survey was sent to each fellowship program director with a list of their graduates asking them to verify the names and to identify those graduates who had pursued a career in academic urology, and whether they had served as fellowship program director, residency program director or department chairperson. Seventeen of the 52 U.S. program directors (33%) responded to the survey. For those programs that did not respond to the survey each graduate's name was searched via Google, LinkedIn, and/or Doximity to determine if they had pursued a career in academic urology and served in a leadership position.
The number of U.S. Endourological Society fellowships has increased from 11 in 1987 to 52 in 2021. Five hundred and seventy-seven fellows have graduated from an Endourological Society Fellowship in the United States from 1987 to 2021. Two hundred and fifty fellows have pursued a career in academic urology (43.3%), 46 have served as fellowship program director (8.0%), 9 as residency program director (1.6%), and 13 have served as department chairperson (2.3%).
The progress of the Endourological Society can be directly tied to the historical growth of its fellowship programs and the pursuit of an academic career by many of its graduates leading them to become the current and future educational leaders in the field.
Influence of renal anatomy on success rates for shockwave lithotripsy has been reported in the literature with emphasis on lower pole anatomy. Influence of renal anatomy has not been evaluated in the ...setting of ureteroscopy and laser lithotripsy for stone treatment. This study analyzed the influence of infundibulopelvic angle (IPA) of the lower pole on the outcomes of ureteroscopy and laser lithotripsy with respect to stone-free rate and surgical recurrence.
We retrospectively analyzed 735 renal units undergoing retrograde flexible ureteroscopy (fURS) with laser lithotripsy between January 2009 and December 2016. All cases were performed at a single institution. No exclusion criterion was applied with regard to preoperative stone location. Success was defined as no evidence of residual stone fragments on kidney, ureter, and bladder radiograph within 2 months of surgery. Failure was defined as any stone present on imaging. Lower pole IPA was measured on intraoperative retrograde pyelogram as described by Elbahanasy et al. Univariate and multivariate analyses of factors contributing to stone-free rate were performed. Secondary outcomes included surgical recurrence-free survival.
Of the 735 cases evaluated, 243 cases had a retrograde pyelogram stored in our Picture Archiving and Communication System (PACS) sufficient for IPA interpretation. Of these patients, 122 (50%) were women. In total, 127 patients (52.3%) were stone free on follow-up imaging, whereas 116 (47.7%) had residual stone burden. In total, 144 (59%) patients had ≤3 mm stone burden on follow-up imaging. In multivariate analysis, residual stone fragments were significantly associated with acute IPA <90° (<0.001), lower pole stones preoperatively (<0.001), and larger stone size (0.001). IPA <90° and larger stone size were both found to be statistically significantly associated with need for repeat surgery.
Our data show that more acute IPA and larger preoperative stone size negatively affect stone-free rate and need for repeat surgery after retrograde fURS with laser lithotripsy for treatment of renal stones.
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