Effectiveness of high-intensity laser light for treating large kidney stones

Introduction. This work analyzes efficacy, convenience, and safety of a high-energy laser light technique for destructing large kidney stones in patients with nephrolithiasis in comparison to other contact methods of nephrolithotripsy.Material and methods. The effectiveness of contact laser nephrolithotripsy is compared to that of hydropneumatic and ultrasonic lithotripsy. Holmium green laser light was used in this laser procedure. For other techniques, Swiss LithoClast Master devices were used. The authors have analyzed outcomes obtained after operating on 73 patients with large and complex kidney stones.Results. To evaluate the effectiveness, basic parameters were taken (degree of kidney cleaning of stones and their fragments, probability of migration of stone fragments, blood loss, duration of surgery, complications, etc.). In addition, the correlation between basic parameters was obtained and analyzed.Conclusion. The present trial has shown that laser contact lithotripsy is the most optimal technique for destructing large and complex kidney stones in comparison to traditional modalities such as contact hydropneumatic and ultrasonic lithotripsy. It takes more time but provides more effective cleaning from calculi.

Comparative Analysis of the Efficacy and Safety of Combined Pneumatic and Ultrasonic Lithotripsy in the Treatment of Patients with Staghorn Nephrolithiasis

Urolithiasis is one of the most common disease encountered in the daily practice of a urologist. Depending on the severity of the course, patients with urolithiasis and, in particular, kidney stones, are often required to have the surgical treatment. The greater problem is deemed to be staghorn nephrolithiasis and the choice of the optimal surgical technique for the elimination of kidney stones. The objective: to evaluate the efficacy and safety of the combined method of fragmentation of coral kidney stones in comparison with standard ultrasound lithotripsy. Materials and methods. A total of 352 percutaneous nephrolithotripsies (PCNL) were performed: 187 (53,1%) – patients who were diagnosed with staghorn calculi. The age of the patients ranged from 26 to 66 (mean age 42,5 years). There were 89 men and 98 women. 78 (41.7%) patients had previously undergone surgical treatment (open surgery or PCNL) of kidney stones, in which recurrent staghorn stones were subsequently identified. Nine (4,8%) patients had bilateral coral calculi. The size of the stone varied from 3,5 to 11,0 cm. Their density ranged from 300 to 1500 Hounsfield units. The most frequent complication of the underlying disease was chronic pyelonephritis – 145 (77,5%) patients. Hydronephrosis on the affected side was diagnosed in 98 (52,4%) patients. A combined pneumatic and ultrasonic lithotripter ShockPulse-SE from Olympus (Japan) was used for breaking kidney stones. We performed PCNL in a combined mode in 41 (21,9%) patients with staghorn nephrolithiasis. Results. In the group of patients using combined pneumatic and ultrasonic lithotripsy, complete removal of the staghorn calculus was achieved in 97,6% of cases (in 40 of 41 patients), whereas in the opposite group, using an ultrasonic lithotripter only in 84,9% (in 124 of 146 patients). The duration of the PCNL operation using the ShockPulse-SE device was from 35 to 130 minutes, on average – 48±5 minutes. The duration of the surgical intervention using an ultrasound lithotripter is from 90 to 180 minutes, an average –105±7 minutes. Blood loss during PCNL using an ultrasonic lithotripter was 200–400 ml, whereas with the ShockPulse-SE apparatus – 100–200 ml. An exacerbation of pyelonephritis was noted in 7 patients (in two patients after PCNL in a combined mode and in five after PCNL using an ultrasonic lithotripter). The mean length of patient hospitalization after surgery ranged from 4 to 10 days. At the same time, the average duration after PCNL using the combined ShockPulse-SE technique was 4±1 days, while after PCNL using an ultrasonic lithotripter it was 6±1 days. Conclusions. The combined technique of lithotripsy with a combined probe for simultaneous pneumatic and ultrasound lithotripsy has shown better results in terms of safety and efficacy compared to using only an ultrasound lithotripter. Used for decades, ultrasound lithotripsy for staghorn stone PCNL is both effective and safe moreover it’s a traditional technique. Thus, in comparison with ultrasound lithotripsy, the combined technique showed a shorter operation time, with less blood loss, a shorter length of patient hospitalization and less pyelonephritis in the postoperative period, as a result of maintaining a lower intrarenal pressure gradient during the operation. At the same time, the cost of the procedure using a combined probe was estimated, which turned out to be higher than traditional ultrasound lithotripsy. The use of combined lithotripsy with simultaneous aspiration of stone fragments is an indisputable advantage of this kind of PCNL in patients with staghorn nephrolithiasis, which brings the effectiveness of this technique closer to 100%.

Outcome of Stone Fragmentation with Pneumatic and Ultrasonic Lithotripter During Percutaneous Nephrolithotomy

Background of the study: Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for kidney stones larger than 2 cm. PCNL has replaced open surgical removal of large or complex calculi at the most institutions. The success of PCNL is related to the ability to achieve an optimum access tract and proper fragmentation. A wide range of lithotripsy techniques are currently available. One of these is ultrasonic lithotripsy, in which the stones are fragmented and sucked out simultaneously. This technique induces minimal tissue injury and could be considered as a standard modality for PCNL. The pneumatic lithotripter uses pneumatic ballast, which crushes the stones without producing any thermal effects. Because this mechanical energy passes along the metal wire to the stone, the probe works like a chisel on the stone surface. This modality destroys all stones, regardless of their composition. There were very few studies had been done in this context in our country, so I had decided to do this study to compare the outcome of stone fragmentation with pneumatic and ultrasonic lithotripter during percutaneous nephrolithotomy. Objective: To compare the outcome of stone fragmentation with pneumatic and ultrasonic lithotripter during percutaneous nephrolithotomy. Materials & Methods: This Prospective Interventional Study (Quasi Experimental Trial) was performed in Department of Urology, National Institute of Kidney Diseases and Urology, Sher-E- Bangla Nagar, Dhaka during the period from December 2014 to May 2016. A total of 60 subjects will be selected with renal calculi (as per inclusion & exclusion criteria), among these, half of the patients will be group A (using pneumatic lithotripsy) & rest of the patients will be group B (using ultrasonic lithotripsy). The study subjects were underwent PCNL under general anesthesia, half of which used pneumatic lithotripter and rest used ultrasonic lithotripter for stone fragmentation. Above mentioned outcome variables were assessed both per-operative and post-operatively. Data were collected, processed & analyzed. Statistical analysis of relevant variables was done by unpaired Student’s T test and Chi Square test. P value Â0.05 was considered significant. Results: Total 60 patients were selected for study according to the selection criteria. Of the 60 subjects, 30 patients, those who were done PCNL by pneumatic lithotripsy were labeled as Group A and 30 patients, those who were done PCNL by ultrasonic lithotripsy, were labeled with Group B. Distribution of respondents in terms of different parameters is shown in tabulated form and statistical analysis was done in both groups to see statistical significance, p value less than 0.05 was considered significant. The mean stone fragmentation time was 27.23±4.78 (18-38) min in PCNL by pneumatic lithotripsy and those were 23.80±5.30 (13-34) min in by ultrasonic lithotripsy which is statistically significant. Other variables of interest which includes stone clearance rate, post operative haematuria and post operative hospital stay, were not statistically significant. Conclusion: Comparing the findings of the present study, results indicate that stone fragmentation time is lesser in ultrasonic lithotripsy than pneumatic lithotripsy in PCNL which decreases the overall operative time. Bangladesh Journal of Urology, Vol. 23, No. 2, July 2020 p.129-135

Establishing the Improved Dynamic Model for the Extracorporeal Ultrasonic Lithotripsy Medical Cooperative Robot

The calculus is one of the common diseases with high incidence. The effective treatment method is extracorporeal ultrasonic lithotripsy. At present, it is low about the intelligent and automatic level of the lithotripter, and it has gradually failed to meet the treatment needs. The extracorporeal ultrasonic lithotripsy medical cooperative robot can solve such problems effectively, and it is equally critical for accurate modeling studies of dynamic models. Based on the previous research and experimental basis, this paper proposes a correction theory to improve the accuracy of the dynamic model for the model error in collaborative robot work. The study first establishes the dynamic model and the solid model of the collaborative robot and then subtracts the value of the dynamic model from the solid model to obtain the modified equation. Finally, the accuracy of the dynamic model is improved by modifying the equation. The experiments show that the kinetic model correction theory is effective and can improve the accuracy of the dynamic model modeling after the correction of the torque equation. The experiments show that the improved dynamic model theory is effective and can improve the modeling accuracy of the dynamic model after the correction of the torque equation. The modified equation has the best correction effect in the 5th degree polynomial and can be used for the extracorporeal ultrasonic lithotripsy medical cooperative robot control.

Intracorporeal techniques of stone fragmentation

The use of intracorporeal lithotripsy for the management of larger ureteral and intrarenal calculi has dramatically improved. Although the choice of intracorporeal fragmentation is frequently based on the location and composition of the stone to be treated, the experience of the clinician and availability of equipment often dictates this decision. Several different modalities of intracorporeal lithotripsy are currently available. Ultrasonic lithotripsy is mainly used for the fragmentation of large renal calculi during percutaneous nephrolithotripsy procedures. Ultrasound is used rarely via an ureteroscopic approach. Significant advances in laser fibres and power generation systems have propelled laser lithotripsy to the treatment of choice for fragmentation of most ureteral stones. Pneumatic lithotripsy consists of a pneumatically driven piston which will fragment stones by direct contact.

Analysis of Postoperative Complications In Urethrolithiasis Treatment Using Intracorporeal Ultrasonic Lithotripsy

The causes of early and late postoperative complications in patients with ureteral calculi during ultrasonic ureterolithotripsy performance were analyzed. 287 early and late postoperative complications of different severity were noted in 204 patients included into the study. During the bivariate analysis of complications causes, the interrelationship with localization in the upper and middle third of the ureter, the size of more than1 cmand a density of more than 1000 Hounsfield units was revealed.Taking into account the high risk of failure and complications, intracorporeal ureterolithotripsy in patients with complicated ureteral calculi, a differentiated approach to the use of devices for the disintegration of the concretion, or other types of surgery should be used in this group of patients.