Influence of pre-stenting on RIRS outcomes. Inferences from patients of the Global Multicentre Flexible Ureteroscopy Outcome Registry (FLEXOR)
Bibliographic record
Abstract
BACKGROUND: Retrograde Intrarenal Surgery (RIRS) is recommended as an alternative to percutaneous nephrolithotomy for stones up to 2 cm. Pre-stenting before RIRS remains controversial with various studies differing in outcomes and recommendations. We aim to understand how pre-stenting influences surgical outcomes. METHODS: A number of 6579 patients from the TOWER group registry were divided into pre-stented (group 1) and non-pre-stented groups (group 2). Patients aged ≥18 years old, with normal calyceal anatomy were enrolled. Patients with ureteric stones, anomalous kidneys, bilateral stones, planned for ECIRS were excluded. RESULTS: Patients are homogeneously distributed in both groups (3112 vs. 3467). The predominant indication for pre-stenting was symptom relief. Overall stone size was comparable, whilst group 1 had a significantly more multiple (1419 vs. 1283, P<0.001) and lower-pole (LP) stones (1503 vs. 1411, P<0.001). The mean operative time for group 2 was significantly longer (68.17 vs. 58.92, P<0.001). Stone size, LP stones, age, recurrence and multiple stones are contributing factors for residual fragments at the multivariable analysis. The incidence of postoperative day 1 fever and sepsis was significantly higher in group 2, indicating that pre-stenting is associated with a lower risk of post-RIRS infection and a lower overall complications rate (13.62% vs. 15.89%) (P<0.001). CONCLUSIONS: RIRS without pre-stenting can be considered safe without significant morbidity. Multiple, lower-pole and large stone is a significant contributor towards residual fragments. Patients who were not pre-stented had significantly higher but low-grade complications, especially for lower pole and large volume stones. While we do not advocate routine pre-stenting, a tailored approach for these patients should include proper counselling regarding pre-stenting.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".