Evaluation of a Novel Temperature-Sensitive Polymer for Temporary Ureteral Occlusion

Prevention of stone retropulsion during ureteroscopy: Limitations in resources invites revival of old techniques

Objective

To compare a modified technique using the Dormia basket vs Stone Cone for stone entrapment to avoid proximal stone migration during ureteroscopic pneumatic lithotripsy of ureteric stones.

Patients and methods

Our study included all patients with ureteric stones of <15 mm who underwent ureteroscopic pneumatic lithotripsy from January 2015 to September 2018. The study had two arms that were conducted over two consecutive periods; the first included 72 patients in whom we used the Stone Cone (Group 1) and the second included 86 patients in whom we started to use a Dormia basket with a modification (Group 2) to guard against proximal stone migration.

Results

Both groups were comparable for gender, age, and stone characteristics. Lower ureteric stones were the most prevalent as they represented 62.5% and 60.5% in groups 1 and 2, respectively; while upper ureteric stones were respectively found in 16.7% and 17.4%. Chemical stone analysis revealed that calcium oxalate stones were most predominant accounting for 51.3% and 51.1% in groups 1 and 2, respectively. Most of the stones were radio-opaque stones representing 57% and 58.1% in groups 1 and 2, respectively. There was a significant difference in operative time, with a mean (SD) operative time was 50.9 (11.2) in Group 1 vs 58.3 (12.4) min in Group 2 (P < 0.001). The success rate, defined as no retropulsion of stone fragments, was 97.7% in Group 2 vs 91.7% in Group 1 (P < 0.01). Complications were minor and comparable between the groups. There was no difference in hospital stay between the groups, but the cost assessment favoured Group 2.

Conclusion

We found that our modified-basket stone entrapment technique compared favourably with the Stone Cone to guard against stone retropulsion during ureteroscopic pneumatic lithotripsy. Our modification to the basket was found to be feasible, efficient, safe, reproducible and cost-effective in preventing proximal stone migration. This procedure is particularly suitable in cost-limited environments.

Advances in ureteroscopy

Ureteroscopy (URS) is a procedure which has been constantly evolving since the development of first generation devices 40 years ago. Progress towards smaller and more sophisticated equipment has been particularly rapid in the last decade. We review the significant steps that have been made toward improving outcomes and limiting morbidity with this procedure which is central to the management of urolithiasis and other upper urinary tract pathology.

Simultaneous saline irrigation during retrograde rigid ureteroscopic lasertripsy for the prevention of proximal calculus migration

OBJECTIVE

In this paper, we analyze the clinical efficacy of a simultaneous saline irrigation method in treating upper-mid ureteral stone migration and evaluate its effectiveness during ureteroscopic lasertripsy.

METHODS

We prospectively evaluated 78 patients with a total of 95 upper-mid ureteral stones, which were treated with holmium:YAG lasertripsy. These patients were randomized into 2 groups. In Group 1 (39 cases with 44 ureteral stones), conventional ureteroscopic lasertripsy was performed. In Group 2, (39 cases with 51 ureteral stones), the simultaneous saline irrigation method was used during lasertripsy. There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by spiral computed tomography or excretory urography. Data were analyzed regarding stone migration, lengths of time, and ureteral clearing for various stages of each procedure.

RESULTS

One patient in Group 2 (2%) experienced upward stone migration, while this occurred in 8 patients in Group 1 (20%). The operative time in Group 1 ranged from 35 to 55 minutes (mean: 44.8 ± 5.3), while in Group 2 it ranged from 40 to 69 minutes (mean: 50.4±3). There was no significant different in the operative times between the two groups (p < 0.05). Ureteral perforation, urinoma and urosepsis were not seen in both groups.

CONCLUSION

The simultaneous saline irrigation method demonstrated a statistically significant advantage over conventional methods. The operation can be performed persistently under clear vision, and since the stones cannot move upward, fragmented portions are easily flushed out. Our data suggest that this method is simple, safe and effective in preventing proximal stone migration during ureteroscopic lasertripsy.

A comparison of Stone Cone versus lidocaine jelly in the prevention of ureteral stone migration during ureteroscopic lithotripsy

BACKGROUND

Intracorporeal lithotripsy modalities and stone removal devices have been created to facilitate endoscopic management of ureteral stones. These devices, along with improved techniques, have resulted in stone-free rates greater than 95% with low morbidity. However, problems remain that preclude consistent 100% stone-free rates with endoscopic treatment of ureteral calculi. Retrograde migration during ureteroscopic procedures remains a significant problem.

OBJECTIVES

The aim of this study was to compare the Stone Cone device and instillation of lubricating lidocaine jelly as two methods to prevent retrograde stone migration during ureteroscopic lithotripsy.

PATIENTS AND METHODS

This study included patients suffering from ureteral stones that were treated with intracorporeal lithotripsy using the pneumatic Lithoclast. These patients were divided into two groups. In group I, the Stone Cone device was used, while in group II, lidocaine jelly 2% concentration was used.

RESULTS

This study included 40 patients with a mean age of 38.6 ± 9.3 years (20 patients in each group). There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by excretory urography. The pneumatic Lithoclast allowed successful fragmentation of all calculi into small fragments. Upward stone migration did not occur in patients in the Stone Cone group, while in the lidocaine jelly group it occurred in three patients (15%). The operative time in the Stone Cone group ranged between 30 and 55 minutes (mean, 41.8 ± 5.3), while in the lidocaine jelly group it ranged between 40 and 71 minutes (mean, 51.4 ± 3.4), and this difference was statistically significant (p < 0.05).

CONCLUSION

The Stone Cone is safe and efficient in preventing proximal stone migration during ureteroscopic pneumatic lithotripsy. It maintained continuous ureteral access and demonstrated a statistically significant advantage over the lidocaine jelly in terms of proximal stone migration, operative time, and the need for auxiliary procedures.