Browsing by Subject "Kidney calculi"
Now showing 1 - 8 of 8
Results Per Page
Sort Options
Item Consultation on kidney stones, Copenhagen 2019: lithotripsy in percutaneous nephrolithotomy(Springer, 2021-06) Axelsson, Tomas Andri; Cracco, Cecilia; Desai, Mahesh; Hasan, Mudhar Nazar; Knoll, Thomas; Montanari, Emanuele; Pérez‑Fentes, Daniel; Straub, Michael; Thomas, Kay; Williams, James C., Jr.; Brehmer, Marianne; Osther, Palle J.S.; Anatomy and Cell Biology, School of MedicinePurpose: To evaluate the balance between existing evidence and expert opinions on the safety and efficacy of new technological improvements in lithotripsy techniques for percutaneous nephrolithotomy (PCNL). Methods: A scoping review approach was applied to search literature in Pubmed, Embase, and Web of Science. Consensus by key opinion leaders was reached at a 2-day meeting entitled "Consultation on Kidney Stones: Aspects of Intracorporeal Lithotripsy" held in Copenhagen, Denmark, in September 2019. Results: New-generation dual-mode single-probe lithotripsy devices have shown favourable results compared with use of ballistic or ultrasonic lithotripters only. However, ballistic and ultrasonic lithotripters are also highly effective and safe and have been the backbone of PCNL for many years. Compared with standard PCNL, it seems that mini PCNL is associated with fewer bleeding complications and shorter hospital admissions, but also with longer operating room (OR) time and higher intrarenal pressure. Use of laser lithotripsy combined with suction in mini PCNL is a promising alternative that may improve such PCNL by shortening OR times. Furthermore, supine PCNL is a good alternative, especially in cases with complex renal stones and large proximal ureteric stones; in addition, it facilitates endoscopic combined intrarenal surgery (ECIRS). Conclusion: Recent technological improvements in PCNL techniques are promising, but there is a lack of high-level evidence on safety and efficacy. Different techniques suit different types of stones and patients. The evolution of diverse methods has given urologists the possibility of a personalized stone approach, in other words, the right approach for the right patient.Item Endoscopic observations as a tool to define underlying pathology in kidney stone formers(Springer, 2019-10) Pless, Maria Sloth; Williams, James Caldwell, Jr.; Andreassen, Kim Hovgaard; Jung, Helene Ulrich; Osther, Susanne Sloth; Christensen, Dorte Ravnsmed; Osther, Palle Jörn Sloth; Anatomy and Cell Biology, School of MedicinePURPOSE: Advancements in endoscopy offer the possibility of inspection of intrarenal anatomy and pathology. The aim of the study was to evaluate renal papillary appearance in kidney stone formers and to correlate papillary findings with stone type and patient metabolic data. MATERIALS AND METHODS: A consecutive cohort of 46 kidney stone formers undergoing retrograde intrarenal surgery was enrolled. During surgery, renal papillae were characterized in the domains of ductal Plugging (DP), surface Pitting, Loss of papillary contour, and Amount of Randall's plaque (RP, PPLA scoring). Stone material was analyzed using micro-CT and infrared spectroscopy, and blood and urine were collected for metabolic evaluation. RESULTS: In all patients, renal papillae had changes in at least one of the domains of the PPLA score. Examining the total population, it was evident that patients with predominantly plugging (DP > 0) all had very low RP scores. There were no significant trends between mean PPLA scores and urinary analytes for the total group. CONCLUSION: Efforts to prevent renal stone formation have so far been insufficient in majority of patients. Digital endoscopy reveals that kidney stone formers have different and distinct papillary morphologies that seem to be linked to specific stone-forming pathways. Since renal papillary abnormalities may be easily identified during endoscopy, this may in the future prove to be an important method for tailoring prevention strategies in kidney stone patients.Item First-in-human clinical trial of ultrasonic propulsion of kidney stones(First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones, 2016-04) Harper, Jonathan D.; Cunitz, Bryan W.; Dunmire, Barbrina; Lee, Franklin C.; Sorensen, Mathew D.; Hsi, Ryan S.; Thiel, Jeff; Wessells, Hunter; Lingeman, James E.; Bailey, Michael R.; Urology, School of MedicinePURPOSE: Ultrasonic propulsion is a new technology using focused ultrasound energy applied transcutaneously to reposition kidney stones. We report what are to our knowledge the findings from the first human investigational trial of ultrasonic propulsion toward the applications of expelling small stones and dislodging large obstructing stones. MATERIALS AND METHODS: Subjects underwent ultrasonic propulsion while awake without sedation in clinic, or during ureteroscopy while anesthetized. Ultrasound and a pain questionnaire were completed before, during and after propulsion. The primary outcome was to reposition stones in the collecting system. Secondary outcomes included safety, controllable movement of stones and movement of stones less than 5 mm and 5 mm or greater. Adverse events were assessed weekly for 3 weeks. RESULTS: Kidney stones were repositioned in 14 of 15 subjects. Of the 43 targets 28 (65%) showed some level of movement while 13 (30%) were displaced greater than 3 mm to a new location. Discomfort during the procedure was rare, mild, brief and self-limited. Stones were moved in a controlled direction with more than 30 fragments passed by 4 of the 6 subjects who had previously undergone a lithotripsy procedure. The largest stone moved was 10 mm. One patient experienced pain relief during treatment of a large stone at the ureteropelvic junction. In 4 subjects a seemingly large stone was determined to be a cluster of small passable stones after they were moved. CONCLUSIONS: Ultrasonic propulsion was able to successfully reposition stones and facilitate the passage of fragments in humans. No adverse events were associated with the investigational procedure.Item Fragmentation of Stones by Burst Wave Lithotripsy in the First 19 Humans(Wolters Kluwer, 2022) Harper, Jonathan D.; Lingeman, James E.; Sweet, Robert M.; Metzler, Ian S.; Sunaryo, Peter L.; Williams, James C., Jr.; Maxwell, Adam D.; Thiel, Jeff; Cunitz, Bryan W.; Dunmire, Barbrina; Bailey, Michael R.; Sorensen, Mathew D.; Urology, School of MedicinePurpose: We report stone comminution in the first 19 human subjects by burst wave lithotripsy (BWL), which is the transcutaneous application of focused, cyclic ultrasound pulses. Materials and methods: This was a prospective multi-institutional feasibility study recruiting subjects undergoing clinical ureteroscopy (URS) for at least 1 stone ≤12 mm as measured on computerized tomography. During the planned URS, either before or after ureteroscope insertion, BWL was administered with a handheld transducer, and any stone fragmentation and tissue injury were observed. Up to 3 stones per subject were targeted, each for a maximum of 10 minutes. The primary effectiveness outcome was the volume percent comminution of the stone into fragments ≤2 mm. The primary safety outcome was the independent, blinded visual scoring of tissue injury from the URS video. Results: Overall, median stone comminution was 90% (IQR 20, 100) of stone volume with 21 of 23 (91%) stones fragmented. Complete fragmentation (all fragments ≤2 mm) within 10 minutes of BWL occurred in 9 of 23 stones (39%). Of the 6 least comminuted stones, likely causative factors for decreased effectiveness included stones that were larger than the BWL beamwidth, smaller than the BWL wavelength or the introduction of air bubbles from the ureteroscope. Mild reddening of the papilla and hematuria emanating from the papilla were observed ureteroscopically. Conclusions: The first study of BWL in human subjects resulted in a median of 90% comminution of the total stone volume into fragments ≤2 mm within 10 minutes of BWL exposure with only mild tissue injury.Item Quantitative prediction of stone fragility from routine single and dual energy CT: proof of feasibility(Elsevier, 2016-12) Ferrero, Andrea; Montoya, Juan C.; Vaughan, Lisa E.; Huang, Alice E.; McKeag, Ian O.; Enders, Felicity T.; Williams, James C.; McCollough, Cynthia H.; Anatomy and Cell Biology, School of MedicineRationale and Objectives Previous studies have demonstrated a qualitative relationship between stone fragility and internal stone morphology. The goal of this study was to quantify morphological features from dual-energy CT images and assess their relationship to stone fragility. Materials and Methods Thirty-three calcified urinary stones were scanned with micro CT. Next, they were placed within torso-shaped water phantoms and scanned with the dual-energy CT stone composition protocol in routine use at our institution. Mixed low-and high-energy images were used to measure volume, surface roughness, and 12 metrics describing internal morphology for each stone. The ratios of low- to high-energy CT numbers were also measured. Subsequent to imaging, stone fragility was measured by disintegrating each stone in a controlled ex vivo experiment using an ultrasonic lithotripter and recording the time to comminution. A multivariable linear regression model was developed to predict time to comminution. Results The average stone volume was 300 mm3 (range 134–674 mm3). The average comminution time measured ex vivo was 32 s (range 7–115 s). Stone volume, dual-energy CT number ratio and surface roughness were found to have the best combined predictive ability to estimate comminution time (adjusted R2= 0.58). The predictive ability of mixed dual-energy CT images, without use of the dual-energy CT number ratio, to estimate comminution time was slightly inferior, with an adjusted R2 of 0.54. Conclusion Dual-energy CT number ratios, volume, and morphological metrics may provide a method for predicting stone fragility, as measured by time to comminution from ultrasonic lithotripsy.Item Removal of Small, Asymptomatic Kidney Stones and Incidence of Relapse(Massachusetts Medical Society, 2022) Sorensen, Mathew D.; Harper, Jonathan D.; Borofsky, Michael S.; Hameed, Tariq A.; Smoot, Kimberly J.; Burke, Barbara H.; Levchak, Branda J.; Williams, James C., Jr.; Bailey, Michael R.; Liu, Ziyue; Lingeman, James E.; Radiology and Imaging Sciences, School of MedicineBackground: The benefits of removing small (≤6 mm), asymptomatic kidney stones endoscopically is unknown. Current guidelines leave such decisions to the urologist and the patient. A prospective study involving older, nonendoscopic technology and some retrospective studies favor observation. However, published data indicate that about half of small renal stones left in place at the time that larger stones were removed caused other symptomatic events within 5 years after surgery. Methods: We conducted a multicenter, randomized, controlled trial in which, during the endoscopic removal of ureteral or contralateral kidney stones, remaining small, asymptomatic stones were removed in 38 patients (treatment group) and were not removed in 35 patients (control group). The primary outcome was relapse as measured by future emergency department visits, surgeries, or growth of secondary stones. Results: After a mean follow-up of 4.2 years, the treatment group had a longer time to relapse than the control group (P<0.001 by log-rank test). The restricted mean (±SE) time to relapse was 75% longer in the treatment group than in the control group (1631.6±72.8 days vs. 934.2±121.8 days). The risk of relapse was 82% lower in the treatment group than the control group (hazard ratio, 0.18; 95% confidence interval, 0.07 to 0.44), with 16% of patients in the treatment group having a relapse as compared with 63% of those in the control group. Treatment added a median of 25.6 minutes (interquartile range, 18.5 to 35.2) to the surgery time. Five patients in the treatment group and four in the control group had emergency department visits within 2 weeks after surgery. Eight patients in the treatment group and 10 in the control group reported passing kidney stones. Conclusions: The removal of small, asymptomatic kidney stones during surgery to remove ureteral or contralateral kidney stones resulted in a lower incidence of relapse than nonremoval and in a similar number of emergency department visits related to the surgery.Item Removal of Small, Asymptomatic Kidney Stones and Relapse(Massachusetts Medical Society, 2022-11-10) Sorensen, Mathew D.; Bailey, Michael R.; Lingeman, James E.; Urology, School of MedicineItem “Trust my morphology”, the key message from a kidney stone(SpringerLink, 2021-10) Pozdzik, Agnieszka; Van Haute, Carl; Maalouf, Naim; Letavernier, Emmanuel; Williams, James C.; Sakhaee, Khashayar; Anatomy and Cell Biology, School of Medicine