Efficacy of pethidine, ketorolac, and lidocaine gel as analgesics for pain control in shockwave lithotripsy: A single-blinded randomized controlled trial oleh Abdelwahab Hashem, Fady K. Ghobrial, M. A. Elbaset, Ahmed M. Atwa, Mohamed Fadallah, Mahmoud Laymon, Ahmed El-Assmy, Khaled Z. Sheir, Hassan Abol-Enein