Predictive Factors for Unsuccessful Holmium: YAG Laser Lithotripsy in the Retrograde Treatment of Proximal Ureteral Stones

Öz

Background: This retrospective study aimed to evaluate clinical and radiological parameters associated with unsuccessful outcomes of semi-rigid ureteroscopy  using holmium: YAG laser lithotripsy in patients with proximal ureteral stones.

Materials and Methods: A total of 212 patients who underwent semi-rigid URS for proximal ureteral stones between 2015 and 2025 were retrospectively analyzed. Patients were classified into three groups according to postoperative outcomes: Group 1 (stone-free, n=158), Group 2 (retropulsion, n=32), and Group 3 (residual fragments >3 mm, n=22). Demographic and stone-related parameters, including hydronephrosis grade, stone density, stone volume, and stone-to-renal pelvis distance, were compared statistically among the groups.

Results: The overall stone-free rate was 74.5%. Severe hydronephrosis was significantly more frequent in the retropulsion group compared to the stone-free group (46.9% vs. 12.7%, p<0.001), and was associated with a 6.1-fold increased risk of stone migration (95% CI: 2.6-14.1, p<0.001). Mean stone density was significantly higher in Group 2 compared to Group 1 (916±239 HU vs. 692±234 HU, p<0.001) and in Group 3 compared to Group 1 (868±191 HU vs. 692±234 HU, p=0.003). Median stone volume was also significantly greater in Group 2 than in Group 1 (459 mm³ vs. 168 mm³, p<0.001). Additionally, stone-to-renal pelvis distance was significantly shorter in Group 2 (7.5 mm vs. 27 mm, p<0.001).

Conclusions: High-grade hydronephrosis, increased stone density, larger stone volume, and shorter stone-to-renal pelvis distance are significantly associated with unsuccessful outcomes of semi-rigid ureteroscopic holmium: YAG laser lithotripsy in proximal ureteral stones. Preoperative evaluation of these parameters may help optimize surgical planning and patient counseling.

Anahtar Kelimeler

• Ureteral stone
• Lithotripsy
• Holmium laser
• Stone free rate

Proksimal Üreter Taşlarının Retrograd Tedavisinde Holmiyum: YAG Lazer Litotripsisinin Başarısızlığını Öngören Faktörler

Öz

Amaç: Bu retrospektif çalışmada, proksimal üreter taşlarında yarı rijit üreteroskopi (URS) eşliğinde uygulanan holmiyum:YAG lazer litotripsinin başarısız sonuçları ile ilişkili klinik ve radyolojik parametrelerin değerlendirilmesi amaçlandı.

Materyal ve metod: 2015-2025 yılları arasında proksimal üreter taşı nedeniyle yarı rijit URS uygulanan toplam 212 hasta retrospektif olarak analiz edildi. Hastalar postoperatif sonuçlara göre üç gruba ayrıldı: Grup 1 (taşsız, n=158), Grup 2 (retropulsiyon, n=32) ve Grup 3 (>3 mm rezidüel fragman, n=22). Demografik veriler ile hidronefroz derecesi, taş dansitesi, taş hacmi ve taşın renal pelvis uzaklığı gibi taşla ilişkili parametreler gruplar arasında istatistiksel olarak karşılaştırıldı.

Bulgular: Genel taşsızlık oranı %74,5 olarak bulundu. Retropulsiyon %15,1, >3 mm rezidüel fragman ise %10,4 oranında saptandı. Şiddetli hidronefroz retropulsiyon grubunda anlamlı derecede daha sık görüldü (%46,9’a karşı %12,7; p<0,001) ve taş migrasyonu için 6,1 kat artmış risk ile ilişkili bulundu (%95 GA: 2,6-14,1; p<0,001). Ortalama taş dansitesi Grup 2’de Grup 1’e göre anlamlı derecede daha yüksekti (916±239 HU’ya karşı 692±234 HU; p<0,001). Medyan taş hacmi retropulsiyon grubunda anlamlı olarak daha fazlaydı (459 mm³’e karşı 168 mm³; p<0,001). Taşın renal pelvis uzaklığı retropulsiyon grubunda anlamlı derecede daha kısa bulundu (7,5 mm’ye karşı 27 mm; p<0,001).

Sonuç: Yüksek dereceli hidronefroz, artmış taş dansitesi, büyük taş hacmi ve renal pelvise kısa mesafe, proksimal üreter taşlarında yarı rijit URS eşliğinde uygulanan holmiyum:YAG lazer litotripside başarısızlık ile anlamlı şekilde ilişkilidir. Bu parametrelerin preoperatif değerlendirilmesi cerrahi planlamaya ve hasta bilgilendirmesine katkı sağlayabilir.

Anahtar Kelimeler

• Üreter taşı
• Litotripsi
• Holmium laser
• Taşsızlık oranı

Kaynakça

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