The study's aim is to determine which treatment modality, either ESWL or RIRS, is more effective in achieving stone clearance for lower calyceal calculi.

Investigators hypothesize that retrograde intrarenal surgery is better as compared to extracorporeal shockwave lithotripsy. It will target those patients suffering from kidney stones in lower calyces with sizes up to 1.5 cm in an open-label, randomized controlled trial.

After approval from the Institutional Ethical Review Committee and taking informed consent from the patients, the investigator will gather all the information related to the study. Patients will be enrolled in this study from the outpatient clinic. Total patients will be divided into two groups using the SNOSE protocol, in which patients will be randomly assigned to one of the two groups using the envelope method.

Group A will be labeled under those patients who will be treated by ESWL. Group B will be those treated by RIRS. It will be an open-label study. A Performa has been designed and finalized after a literature search. This form will gather demographic details, clinical characteristics, selection of procedure, procedure details, outcomes of procedure, and complications.

In case of ESWL, up to 3 sessions of ESWL will be given, and for RIRS, only one session will be considered. In ESWL, ultrasound- or fluoroscopy-guided 3000 shock waves per person are delivered under the supervision of an experienced consultant urologist for up to 60 - 90 minutes using lithotripsy model SLX-F2 FD21 with energy ranging from 1 to 6, and patients are discharged on proper hydration, painkillers, and alpha blockers. In RIRS, firstly, a retrograde pyelogram is performed to know the anatomy and stone position. Then, using aseptic technique, a sterile flexible 7.5/3.6 Fr ureterorenoscope of model HU30S will be passed over a Y-9-50 ureteral access sheath and advanced into the kidney, and the stone will be broken with the use of a 35-watt hyperphotonic holmium laser delivered via a 272 nm fiber. The RIRS will be performed by an experienced urologist. Later patients will be discharged with advice of hydration and empirical antibiotics. Initially the stone bulk will be defined by a CT scan, and the Hounsfield unit of stones will be noted. The infundibular pelvic angle, calyx length, diameter, and skin-to-stone distance will also be calculated using the CT scan plane. Patients managed either by RIRS or ESWL will be advised for a follow-up after four weeks with an X-ray KUB for radiopaque stones and an ultrasound and CT scan of the kidneys to look for residual radiolucent calculi. Stone clearance will be considered if residual stone size is less than 4 mm.

Inclusion Criteria

• Those patients will be included with lower calyceal renal stones and size up to 1.5 cm.
• Patients' ages will be between 18 and 60 years.
• Both genders will be included.

Exclusion Criteria:

• Untreated Urine culture positive will be excluded
• Patients using anticoagulants and females with pregnancies and those lactating will be excluded.
• Anatomical abnormalities like horseshoe kidney, duplex system, pelvic kidney, malrotated kidney, calyceal diverticulum, steep infundibulopelvic angle, infundibular stenosis, long infundibular length/narrow infundibular width, pelvic ureteric junction obstruction, ureterocele, and ureteral stricture will be excluded.

Only results will be shared