Vacuum-assisted mini-percutaneous nephrolithotomy is associated with lower rates of infectious complications compared to vacuum-cleaner procedure in patients at high risk for infections: a single-center experience

Development and validation of a deep learning-based automated computed tomography image segmentation and diagnostic model for infectious hydronephrosis: a retrospective multicentre cohort study

Background

Accurately diagnosing whether hydronephrosis is complicated by infection is crucial for guiding appropriate clinical treatment. This study aimed to develop a fully automated segmentation and non-invasive diagnostic model for infectious hydronephrosis (IH) using CT images and a deep learning algorithm.

Methods

A retrospective analysis of clinical information and annotated cross-sectional CT images from patients diagnosed with hydronephrosis between June 2, 2019 and June 30, 2024 at the Sun Yat-Sen Memorial Hospital (SYSMH), Heyuan People's Hospital (HPH), and Ganzhou People's Hospital (GPH) was performed. Data on cases of hydronephrosis were extracted from the hospital's medical record system. The SYSMH cohort was randomly divided into two subsets: the SYSMH training set (n = 279) and the SYSMH validation set (n = 93) in a 3:1 ratio. The HPH cohort and GPH cohort serve as external validation sets. A hydronephrosis segmentation model (HRSM) was developed using the Improved U-Net algorithm, and the segmentation accuracy evaluated by the Dice Similarity Coefficient (DSC). Using 3D Convolutional Neural Network established an IH risk score (IHRS) based on segmented images. Independent risk clinical data for IH were screened by logistic regression. An IH diagnostic model (IHDM) was then developed, incorporating the IHRS and clinical data, using five machine learning algorithms (Random Forests, K-Nearest Neighbor, Decision Tree, Logistic Regression and Support Vector Machine). The diagnostic performance of the IHDM was assessed by the Receiver Operating Characteristic (ROC) curve.

Findings

The study initially included 1464 potential eligible cases, of which 864 were deemed qualified after preliminary examination. Ultimately, a total of 615 patients (363 female and 252 male) with hydronephrosis (including 5876 annotated cross-sectional CT images) were included in the study, 372 of whom were from SYSMH, 123 from HPH, and 120 from GPH. Based on bacterial culture results from percutaneous nephrostomy drainage of hydronephrosis, 291 cases were classified as IH, while 324 were non-IH. The DSC for the HRSM in the internal and two external validation cohorts were 0.922 (95% CI: 0.895, 0.949), 0.906 (95% CI: 0.869, 0.943), and 0.883 (95% CI: 0.857, 0.909), respectively, indicating high segmentation accuracy. The IHRS achieved a prediction accuracy of 78.5% (95% CI: 78.1%-78.9%) in the internal validation set. The IHDM developed using Support Vector Machine (SVM) combination with blood neutrophil count, fever within one week of history and IHRS performed best, demonstrated areas under the ROC curve of 0.919 (95% CI: 0.859-0.980), 0.902 (95% CI: 0.849-0.955), and 0.863 (95% CI: 0.800-0.926) in three cohorts, respectively.

Interpretation

The automated HRSM demonstrated excellent segmentation performance for hydronephrosis, while the non-invasive IHDM provided significant diagnostic efficacy, facilitating infection assessment in patients with hydronephrosis. However, more diverse real-world multicenter validation studies are needed to verify the robustness of the model before it can be incorporated into clinical practice.

Funding

The Key-Area Research and Development Program of Guangdong Province, and the National Natural Science Foundation of China.

Safety and efficacy of vacuum-assisted mini-percutaneous nephrolithotomy for the treatment of renal stone disease: an analysis of stone free status and postoperative infectious complications

PURPOSE

Vacuum-assisted mini-percutaneous nephrolithotomy (vmPCNL) is being increasingly adopted due to its faster operating times and lower incidence of postoperative infectious complications (IC), however, studies have been limited by small sample sizes. We hypothesize that vmPCNL is an efficacious treatment for renal stone disease with acceptable stone-free rates (SFR) and low incidence of IC. The objectives of this study were to measure SFR three months after surgery, determine the factors influencing SFR, and determine the rates of postoperative IC after vmPCNL.

MATERIALS AND METHODS

Seven hundred and sixty seven patients underwent vmPCNL for the treatment of renal stones > 20 mm at a single institution. Patients underwent postoperative computed tomography at three months to assess SFR. Postoperative fever and SIRS/Sepsis were recorded for individual patients. Multivariate logistics regression was performed to assess predictors of SFR.

RESULTS

The SFR was found to be 73.7% at three months. Stone burden (OR 0.39, 95% CI [0.33-0.46]) and age (OR 1.03, 95% CI [1.01-1.04]) emerged as statistically significant predictors of SFR on multivariate analysis. 5.5% of patients experienced postoperative fever, while 2.9% experienced SIRS/Sepsis.

CONCLUSIONS

This is the largest continuous cohort of patients to undergo vmPCNL for stone disease and demonstrates that vmPCNL is safe and efficacious, with an SFR of 74% at three months. The incidence of postoperative fever and SIRS/Sepsis is 5.5% and 2.9% respectively. Further randomized studies with large sample sizes are required to ascertain the rates of these complications in comparison to conventional approaches.

Holmium:yttrium-aluminium-garnet laser with MOSES technology is more efficient than thulium fibre laser in supine mini-percutaneous nephrolithotomy

OBJECTIVES

To address the paucity of literature comparing outcomes achieved with utilisation of the high-power holmium:yttrium-aluminium-garnet (Ho:YAG) laser with MOSES technology vs those achieved with the thulium fibre laser (TFL) in mini-percutaneous nephrolithotomy (PCNL).

METHODS

A retrospective review was performed of patients undergoing supine mini-PCNL between August 2021 and May 2023. Exclusion criteria were urinary diversion, simultaneous utilisation of >1 laser platform, use of any other form of fragmentation, and ureteric stones. The Ho:YAG platform (Lumenis Pulse P120H™ with MOSES technology, 120W; Boston Scientific®) and the TFL (Soltive SuperPulsed Thulium Fibre [SPTF], 60W; Olympus®) were compared. Data on stone-free rate (SFR) were determined by computed tomography performed on the first postoperative day and presented as absence of stone fragments, no fragments larger than 2 mm, or no fragments larger than 4 mm.

RESULTS

A total of 100 patients met the inclusion criteria, 51 mini-PCNLs with the Ho:YAG laser and 49 with the SPTF laser. No significant differences in demographics or stone characteristics were detected between the two groups. The Ho:YAG laser utilised less energy and time, resulting in higher ablation efficiency (P < 0.05) and less total operating time (P < 0.05). Overall, there was no difference in SFR in any category between the Ho:YAG group and the SPTF group (no fragments: relative risk [RR] 0.81, 95% confidence interval [CI] 0.59-1.12, P = 0.21; fragments <2 mm: RR 0.86, 95% CI 0.67-1.10, P = 0.23; fragments <4 mm: RR 0.96, 95% CI 0.80-1.15, P = 0.67).

CONCLUSIONS

Although we observed an equivalent postoperative SFR, this study supports a shorter operating time and greater intra-operative laser efficiency with the Ho:YAG laser over the SPTF laser in mini-PCNL.