In Vitro Evaluation of Nitinol Stone Retrieval Baskets for Flexible Ureteroscopy

Ureterorenoscopic lithotripsy for pediatric kidney stones using Holmium: YAG laser devices: 15 W versus 30 W

Introduction We aimed to compare the effectiveness of 15Watt (W) and 30 W Holmium: yttrium-aluminum-garnet (Ho: YAG) laser devices used in the treatment of pediatric kidney stones. Methods: Eighty-six consecutive pediatric patients who underwent retrograde intrarenal surgery between February 2010 and August 2020 were enrolled in the study. After exclusion criteria, the data of 79 children were evaluated retrospectively. Patients were divided into two groups according to the laser device power 15W (Group 15: N=30) and 30W (Group 30: N=49). The groups were compared according to demographic, stone feature, and clinical efficacy. Results The age, gender, height, weight, stone characteristics were similar between the groups. The mean operation time was shorter in Group 30. The stone-free rate after the first RIRS session (SF1) was 66.7% in Group 15 and 83.3% in Group 30. SF1 rate after the first RIRS procedure for 20 mm or larger kidney stones was found 0% in Group 15 and 62.5% in Group 30. However, there was no statistically significant difference between the two groups in terms of stone-free rate. Conclusion: In pediatric kidney stone treatment, 30 W Ho:YAG laser devices should be preferred as they shorten the operation time compared to 15 W devices and provide final stone-free with fewer procedures, especially in large kidney stones.

Evaluation of the use of NGage® Nitinol stone extractor for intraocular foreign body removal

PURPOSE

To describe a novel technique to use the NGage® Nitinol Stone Extractor for large IOFB extraction.

METHODS

We conducted a retrospective case series study by reviewing the data of 4 eyes with retained large IOFB extracted with the use of the NGage® Nitinol Stone Extractor. The study was conducted in a single tertiary referral center on four eyes of four patients with large retained IOFB. Studied eyes were treated by pars plana vitrectomy (PPV) and IOFB extraction by using the NGage® Nitinol Stone Extractor through a limbal incision.

RESULTS

Four eyes of four male patients with large Retained IOFB were included in the study. The nature of the IOFB was metallic in 2 eyes, glass in 1 eye or ceramic 1 eye. All the IOFB were removed from a limbal wound. Silicone oil tamponade was required in 3 eyes. Two eyes required reoperation. At 6 months postoperative, the final visual acuity using Snellen chart ranged between PL and 0.1.

CONCLUSION

The NGage® Nitinol Stone Extractor can be a useful tool for the extraction of the large retained IOFB.

Tipless Nitinol Stone Baskets: Comparison of Penetration Force, Radial Dilation Force, Opening Dynamics, and Deflection

OBJECTIVE

To evaluate 5 commercially available tipless nitinol baskets (2.2F) in 4 performance factors: penetration force, radial dilation force, opening dynamics, and deflection limitation.

MATERIALS AND METHODS

The 2.2F Coloplast Dormia No-Tip, 1.5F Sacred Heart Medical Halo, 2.2F Cook NCircle Nitinol Tipless Stone Extractor, 1.9F Bard SkyLite Tipless Nitinol Basket, and 1.9F Boston Scientific Zero Tip Nitinol Stone Retrieval Basket were tested for penetration force (safety metric), radial dilation force (functional metric for ureteral calculi), and opening or closing dynamics. Limitation of deflection (functional metric) was tested by measuring the difference in maximal upward and downward angle of deflection of a ureteroscope with and without a basket in place.

RESULTS

The Sacred Heart Medical Halo 1.5F basket had the highest mean force required to perforate the foil at 0.676N ± 0.117 (P < .0001). The Sacred Heart Medical Halo 1.5F basket also had the highest mean radial dilation force at 3.04 g ± 0.15 (P < .0001). The Cook NCircle Nitinol Tipless Stone Extractor 2.2F had the most linear pattern of opening, whereas the Coloplast Dormia No-Tip 2.2F and the Sacred Heart Medical Halo 1.5F exhibited exponential opening dynamics. The Cook NCircle Nitinol Tipless Stone Extractor 2.2F limited scope deflection the most with a decrease in 4° downward and 10° upward. The Sacred Heart Medical Halo 1.5F had the least influence on deflection with a decrease in 3° downward and 5° upward.

CONCLUSION

The penetration force, radial dilation force, opening dynamics, and resistance to deflection varied between 5 commonly available tipless nitinol stone baskets. A small diameter 1.5F basket is capable of providing optimal performance while sacrificing linear opening.

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.