The term "Percutaneous nephrolithotomy" (PCNL) refers to a minimally invasive procedure that is also well known for removing renal calculi greater than 2 cm in size. PCNL has become the most widely utilised technique for treating renal stones since Fernstorm and Johansson first documented removing renal calculus using a nephrostomy channel in 1976.[1] It facilitates a direct approach to the calculus while the kidney and surrounding structures are subjected to lesser trauma as compared to the open approach, and hence a great deal of surgical expertise is required for percutaneous access to the kidney and stone removal. It has gradually, evolved to be one of the main endourologic treatment options. With the introduction of other treatment modalities such as extracorporeal shock wave lithotripsy (ESWL) [2] and ureterorenoscopy [3], the indications for percutaneous stone surgery have changed. Initially, patients unfit for open surgery were referred for the percutaneous approach. Later, the indications were broadened to include particular situations such ureteral [4] and calyceal diverticular [5] stones as a result of improvements in energy delivery and intraoperative visualisation. Miniaturized tools were created in an effort to lower morbidity without reducing the procedure's effectiveness or percentage of patients without stones. [6] The improvements to PCNL techniques included not just a reduction in the diameter of the working instruments but also better patient placement, safer and more precise tract formation techniques, new imaging modalities, advancements in intracorporeal lithotripters, and the use of flexible devices for effective collecting system screening. Urinary stone disease management constitutes today more than a third of the surgical volume of a contemporary urological department.[7] Percutaneous nephrolithotomy (PCNL) has evolved as the preferred treatment for large and complex renal calculi, supported by AUA and EAU guidelines. Since its inception in 1976, technical refinements have improved efficacy and reduced morbidity. This study from Index Medical College presents outcomes of 60 patients who underwent PCNL, focusing on stone clearance, perioperative complications, hospital stay, and recovery. The thesis also intended to evaluate renal clearance outcomes; however, numerical renal clearance values were not located in the accessible sections.

Design: Prospective observational study at Index Medical College (March 2021–September 2022). Inclusion: Adults with renal calculi indicated for PCNL. Exclusion criteria included unfit for surgery as per thesis protocol. Surgical technique: Under regional (spinal) anesthesia, patients underwent ureteral catheter placement in lithotomy, then prone positioning. Percutaneous access under fluoroscopy was obtained using an 18G needle, guidewire insertion, and tract dilation to 30F using metal and Amplatz dilators. A 24-F rigid nephroscope was used for stone fragmentation and extraction; adjunctive measures (stone forceps, mechanical lithotripsy) employed as needed. Nephrostomy tube or drain placement was at surgeon's discretion. Outcomes: Primary outcome was stone-free rate (SFR) defined by absence of residual fragments on postoperative imaging (KUB/CT/APG). Secondary outcomes included intraoperative complications, postoperative complications, duration of surgery, hospital stay, time to recovery, and patient satisfaction. Statistical analysis used descriptive statistics and Fisher’s exact test where appropriate.

A total of 60 patients underwent PCNL and were included in the analysis. Key demographic and outcome data are summarized below with supporting figures. Table 1. Age and sex distribution (n=60) Age group 18-20 21-30 31-40 41-50 >50 Male 0 7 15 7 7 Female 3 10 4 5 2 Table 2. Residual Stone (n = 60) Residual stone n % No 51 85.0% Yes 9 15.0% Table 3. Intra-operative Complications (n = 60) Intra-op complication n % No complication 50 83.3% Hemorrhage 8 13.3% Tear 1 1.7% Extravasation 1 1.7% Intra-operative complications occurred in 16.7% (10/60) with hemorrhage in 8 patients (13.3%). Post-operative complications occurred in 13.3% (8/60), most commonly surgical site infection (5%). There were no mortalities. Table 4. Post-operative Complications (n = 60) Post-op complication n % No complication 52 86.7% SSI 3 5.0% UTI 1 1.7% Delayed hemorrhage 1 1.7% Nephro-cutaneous fistula 2 3.3% Sepsis 1 1.7% Mean hospital stay was 2.57 ± 0.99 days; 56 patients (93.3%) were discharged within 3 days. Mean time to full recovery was 5.19 ± 1.35 days.

This prospective series reports an SFR of 85% after primary PCNL, comparing favorably with many published series. Intra- and postoperative complication rates were within expected ranges; hemorrhage was the most frequent intraoperative complication. Short hospital stay (mean 2.57 days) reflects efficient perioperative care and single-stage management in most patients. Factors influencing stone clearance include stone burden (size, staghorn morphology), history of prior ipsilateral surgery, and the number of access tracts. The 9 patients with residual stones mostly had complex stone burden requiring additional procedures. The study's strengths include its prospective design and standardized surgical technique performed by a single experienced surgeon, minimizing inter-operator variability. Limitations include a modest sample size, single-center design, and lack of available numeric renal clearance data within the accessible thesis excerpts; renal function trends and specific clearance measurements should be included in future reports for comprehensive renal outcome assessment. Clinical implications: The high SFR, low morbidity, and brief hospitalization support PCNL as an effective intervention for larger renal stones when performed by experienced teams. Optimizing preoperative imaging and intraoperative techniques may further reduce residual fragments.

PCNL in this cohort achieved an 85% stone-free rate with acceptable complication rates and short hospital stays. It remains the treatment of choice for large and complex renal stones in experienced hands. Inclusion of renal clearance metrics will strengthen future analyses; these were not retrievable from the thesis excerpts available for this summary.

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