Sarkar D. et al., 2022: Efficacy of supine trans-abdominal pronated shock head ESWL for treatment of distal ureteric stones: A pilot study.
Sarkar D, Wakle DU, Pal DK.
Department of Urology, Institute of Postgraduate Medical Education and Research, Kolkata, India.
Abstract
Objective: To evaluate the efficacy of extracorporeal shockwave lithotripsy (ESWL) in supine trans-abdominal approach for distal ureteric calculi and to determine the variables that could affect the outcome results.
Materials and methods: Between November 2019 and January 2021, 172 patients with a solitary distal ureteric calculus were treated with ESWL in supine position with a pronated shock wave head against the anterior abdominal wall. The outcome of treatment evaluated and the clinical and radiological findings, as well as stone characteristics, were reviewed and correlated with the stone-free rate (SFR).
Results: Overall SFR was 84.84% (140/165). Those with stone clearance, 83.57% (117/140) cleared after one session and 16.42% (23/140) needed more than one session. Only three factors had a significant impact on SFR, that is stone length, stone width, stone attenuation. For stone length ⩽ 9 mm SFR was 93.44% (114/122) compared to 60.46% (26/43) for stone length of 10-12 mm (p < 0.00001). There were statistically significant increased SFR for stones with attenuation of <0.0001 and for the mean stone width of 8.02 mm (p < 0.00001). Stone localisation was easy with good patient comfort.
Conclusion: Supine trans-abdominal ESWL is a new, effective and safe form of treatment for distal ureteric calculi. The stone length, stone width along with stone attenuation were the only significant predictors of stone free status in supine position.
Urologia. 2022 Apr 15:3915603221091080. doi: 10.1177/03915603221091080. Online ahead of print. PMID: 35422154
Comments 1
With which method distal ureteral stones best should be removed has remained a matter of debate over the years. Generally, results of SWL are good and it is in my mind surprising that various guidelines recommend URS as first line treatment of ureteral stones. I agree with the authors of this report that there are obvious advantages of choosing a non-invasive method that does not require general or regional anaesthesia.
In this article the authors report their experience of SWL in supine position with pronated therapy head. It needs to be noticed that this approach only is possible when the therapy head can be turned to a position above the patient. If this is not possible patients must be placed in prone position for similar transabdominal direction of the shockwaves. My personal experience, however, is that patients do not find the prone position particularly uncomfortable or that this position negatively affects respiration.
One aspect in this article that is surprising to me is the low use of analgesics. Administration of only diclofenac might be insufficient, particularly for treating larger stones and it can be assumed that with adequate pain-relief the failure of 15 percent had been much lower. In my experience the power should be adapted to the course of stone disintegration and not to the pain tolerance of the patient. Sufficient analgesics always should be given to maintain an optimal level of ambition.
With this comment it is necessary to consider that there is no absolute best treatment position for distal ureteral stones. With advantage some stones can be treated by directing shockwaves through the sciatic foramen from the back whereas others are better treated by directing shockwaves transabdominally.
In this report the results are good and obviously there was no interference between the shockwave path and intestinal gas.
The conclusion is that it is necessary to utilize all available tricks that can maintain SWL at high quality level while avoiding organisational obstacles.
Hans-Göran Tiselius