Lasers in percutaneous renal procedures

Safety During Ureteroscopy: Radiation, Eyes, and Ergonomics

It is known that urologic surgeons are at risk of work-place injury due to the physical requirements of operating and exposure to hazards. These hazards include radiation, exposure to body fluids, use of laser energy, and orthopedic injury due to the physical nature of operating. The risks that these hazards present can be mitigated by implementing several evidence-based safety measures. The methods to protect against radiation exposure include keeping radiation usage in the operating room as low as reasonably achievable, donning lead aprons, and wearing protective glasses. Additionally, protective glasses decrease the risk of eye injury from laser injury and exposure to body fluids. Finally, practicing sound surgical ergonomics is essential to minimize the risk of orthopedic injury and promote career longevity. The interventions discussed herein are simple and easy to implement in one's daily practice of urology.

Fragmentation targeted at preferred discontinuities: A new concept in endolithotripsy with Holmium laser:YAG

INTRODUCTION

There are currently 3holmium laser, YAG (Ho:YAG) endolithotripsy procedures that are considered basic (fragmentation, pulverisation, "pop-corn" technique). We present the technique of fragmentation targeted at preferred discontinuities (FTPD), a new concept of endolithotripsy by Ho:YAG laser.

MATERIAL AND METHODS

The FTPD technique is based on the selective application of energy (targeting a specific preselected point) to an area that is visually prone to the formation of a fracture line or preferred discontinuity (conditioned by the anisotropy of the urolithiasis). The ideal energy regimen (setting) is a high range of working energy (2-3J) with a very low frequency range (5-8Hz) and short pulse width. Between January 2015 to February 2017, the FTPD technique was used in 37 procedures (7 NLP, 16 RIRS, 12 URS, 2 cystolithotomies), with a Ho:YAG laser (Lumenis Pulse 120H^®, Tel-Aviv, Israel). Maximum power used: 24W (3J/8Hz) with fibres of 365μ and 273μ (URS, RIRS), and 32W (4J/8Hz) with fibres of 550μ (NLP, cystolithotomy).

RESULTS

Strategic improvement was achieved in all cases using the TFPD technique to continue the endolithotripsy or remove fragments. No complications were recorded after the use of this method.

CONCLUSIONS

FTPD can be considered a complementary option in combination with the basic methods of fragmentation and pulverisation. In our experience, it constitutes significant progress in optimising the performance of Ho:YAG laser endolithotripsy.

Laser Application in Iran Urology: A Narrative Review

The usage of laser in medicine is not recent, and its history in urology goes back to 40 years ago. For the last 2 decades, common uses of laser have been treatments of subjects with urolithiasis, bladder tumors, benign prostatic enlargement, lesions of the genitalia and urinary tract strictures. To evaluate laser application in urology in Iran, we reviewed all of the Iranian literature on the topic. This study was designed to retrieve all studies on laser application in urology in Iran, regardless of publication status or language, covering years 1990-2017. Twenty-six articles were identified: 12 about urolithiasis, 8 about benign prostatic hyperplasia (BPH), 2 case reports, 1 paper about prostate cancer, 1 on female urethral stricture, 1 review and 1 basic sciences study. We conclude that the use of this technology has not yet found its position in Iran, especially in the field of urology. The main causes for it are the difficult accessibility and disturb of laser devices and its accessories, as well as the lack of adequate knowledge of the medical community about this modality.

Jackets Off: The Impact of Laser Fiber Stripping on Power Output and Stone Degradation

PURPOSE

To investigate the effect of laser fiber stripping on stone fragmentation and laser fiber power output.

MATERIALS AND METHODS

In a benchtop simulation of laser lithotripsy, 20 BegoStone phantoms were positioned within a ureteral model and irradiated for 10 minutes at 8 Hz and 0.8 J. A freshly cleaved 365 μm laser fiber was used for all trials, with half of the fibers also undergoing stripping. Power output was measured at 1-minute intervals, beginning with an initial prelithotripsy recording at 0 minutes. Fiber tips were imaged with scanning electron microscopy. In a single-blinded manner, final masses of residual stone fragments were measured and used to quantify stone breakdown. Independent-sample Mann-Whitney U tests were performed with significance set at p < 0.05, comparing stripped and unstripped fiber tips with respect to power output and fraction of stone fragmentation.

RESULTS

Mean power output after 1 minute of lasing was significantly greater in unstripped laser fibers (p = 0.015), while fibers, whether stripped or not, demonstrated no significant output differences prelithotripsy or at any time from 2 to 10 minutes. However, stripped laser fibers achieved significantly increased stone breakdown compared to unstripped fibers (p = 0.004), fragmenting 63 mg (25%) more of the initial stone mass per trial.

CONCLUSIONS

Although unstripped laser fibers provided superior power output at 1 minute, output at all other time points was similar between stripped and unstripped fibers. However, despite similar optical output, stripped laser fibers achieved greater stone fragmentation, possibly due to improved contact between stone and fiber tip.

Advances in ureteroscopy

Recent innovations in imaging equipment and novel instrumentation have helped ureteroscopy evolve from a diagnostic to a therapeutic tool. In this review, the authors highlight several of the most recent advances in ureteroscopy that have helped allow unprecedented access, visualization, and treatment of upper urinary tract pathologic conditions.

Urinary tract stone disease: are all problems solved?

During the past four decades there have been dramatic developments in the methods used for active stone removal from the urinary tract, and the need for open surgery has been almost entirely replaced by extracorporeal shockwave lithotripsy, percutaneous surgery, ureteroscopy and retrograde intrarenal surgery. Residual fragments and the pronounced risk of recurrent stone formation remain important problems for the future development of urolithology and for the optimal low-risk management of this large group of patients. It is emphasized that all aspects of the care of patients with stone disease are the responsibility of the urologist.

The evolution of lasers in urology

The world's first laser was developed by Theodore Maiman in 1960. Over the course of the past five decades, this technology has evolved into a highly specialized entity, also finding a niche market in the field of urology. Lasers obtained from various lasing mediums producing amplified light of different wavelengths have been tested for urological applications. Today, these lasers are most commonly used in the surgical management of benign prostatic hyperplasia and as intracorporeal lithotripters. Other uses include ablation of various urologic tumors and incising strictures of the upper- and lower urinary tract. A continuous process of evolution of this technology is taking place, resulting in surgical lasers becoming ever safer, more effective, and more affordable.