Towards safer robot-assisted surgery: A markerless augmented reality framework.

Robot-assisted surgery is rapidly developing in the medical field, and the integration of augmented reality shows the potential to improve the operation performance of surgeons by providing more visual information. In this paper, we proposed a markerless augmented reality framework to enhance safety by avoiding intra-operative bleeding, which is a high risk caused by collision between surgical instruments and delicate blood vessels (arteries or veins). Advanced stereo reconstruction and segmentation networks are compared to find the best combination to reconstruct the intra-operative blood vessel in 3D space for registration with the pre-operative model, and the minimum distance detection between the instruments and the blood vessel is implemented. A robot-assisted lymphadenectomy is emulated on the da Vinci Research Kit in a dry lab, and ten human subjects perform this operation to explore the usability of the proposed framework. The result shows that the augmented reality framework can help the users to avoid the dangerous collision between the instruments and the delicate blood vessel while not introducing an extra load. It provides a flexible framework that integrates augmented reality into the medical robotic platform to enhance safety during surgery.

Spatio-temporal layers based intra-operative stereo depth estimation network via hierarchical prediction and progressive training.

BACKGROUND AND OBJECTIVE: Safety of robotic surgery can be enhanced through augmented vision or artificial constraints to the robotl motion, and intra-operative depth estimation is the cornerstone of these applications because it provides precise position information of surgical scenes in 3D space. High-quality depth estimation of endoscopic scenes has been a valuable issue, and the development of deep learning provides more possibility and potential to address this issue. METHODS: In this paper, a deep learning-based approach is proposed to recover 3D information of intra-operative scenes. To this aim, a fully 3D encoder-decoder network integrating spatio-temporal layers is designed, and it adopts hierarchical prediction and progressive learning to enhance prediction accuracy and shorten training time. RESULTS: Our network gets the depth estimation accuracy of MAE 2.55±1.51 (mm) and RMSE 5.23±1.40 (mm) using 8 surgical videos with a resolution of 1280×1024, which performs better compared with six other state-of-the-art methods that were trained on the same data. CONCLUSIONS: Our network can implement a promising depth estimation performance in intra-operative scenes using stereo images, allowing the integration in robot-assisted surgery to enhance safety.

Penile-Sparing Surgery for Tumour Recurrence after Previous Glansectomy/Partial Penectomy: Treatment Feasibility and Oncological Outcomes.

We tested the feasibility and oncological outcomes after penile-sparing surgery (PSS) for local recurrent penile cancer after a previous glansectomy/partial penectomy. We retrospectively analysed 13 patients (1997-2022) with local recurrence of penile cancer after a previous glansectomy or partial penectomy. All patients underwent PSS: circumcision, excision, or laser ablation. First, technical feasibility, treatment setting, and complications (Clavien-Dindo) were recorded. Second, Kaplan-Meier plots depicted overall and local recurrences over time. Overall, 11 (84.5%) vs. 2 (15.5%) patients were previously treated with glansectomy vs. partial penectomy. The median (IQR) time to disease recurrence was 56 (13-88) months. Six (46%) vs. two (15.5%) vs. five (38.5%) patients were treated with, respectively, local excision vs. local excision + circumcision vs. laser ablation. All procedures, except one, were performed in an outpatient setting. Only one Clavien-Dindo 2 complication was recorded. The median follow-up time was 41 months. Overall, three (23%) vs. four (30.5%) patients experienced local vs. overall recurrence, respectively. All local recurrences were safely treated with salvage surgery. In conclusion, we reported the results of a preliminary analysis testing safety, feasibility, and early oncological outcomes of PSS procedures for patients with local recurrence after previous glansectomy or partial penectomy. Stronger oncological outcomes should be tested in other series to optimise patient selection.

FRSR: Framework for real-time scene reconstruction in robot-assisted minimally invasive surgery.

3D reconstruction of the intra-operative scenes provides precise position information which is the foundation of various safety related applications in robot-assisted surgery, such as augmented reality. Herein, a framework integrated into a known surgical system is proposed to enhance the safety of robotic surgery. In this paper, we present a scene reconstruction framework to restore the 3D information of the surgical site in real time. In particular, a lightweight encoder-decoder network is designed to perform disparity estimation, which is the key component of the scene reconstruction framework. The stereo endoscope of da Vinci Research Kit (dVRK) is adopted to explore the feasibility of the proposed approach, and it provides the possibility for the migration to other Robot Operating System (ROS) based robot platforms due to the strong independence on hardware. The framework is evaluated using three different scenarios, including a public dataset (3018 pairs of endoscopic images), the scene from the dVRK endoscope in our lab as well as a self-made clinical dataset captured from an oncology hospital. Experimental results show that the proposed framework can reconstruct 3D surgical scenes in real time (25 FPS), and achieve high accuracy (2.69 ± 1.48 mm in MAE, 5.47 ± 1.34 mm in RMSE and 0.41 ± 0.23 in SRE, respectively). It demonstrates that our framework can reconstruct intra-operative scenes with high reliability of both accuracy and speed, and the validation of clinical data also shows its potential in surgery. This work enhances the state of art in 3D intra-operative scene reconstruction based on medical robot platforms. The clinical dataset has been released to promote the development of scene reconstruction in the medical image community.

A Novel Nomogram to Identify Candidates for Focal Therapy Among Patients with Localized Prostate Cancer Diagnosed via Magnetic Resonance Imaging-Targeted and Systematic Biopsies: A European Multicenter Study.

BACKGROUND: Suitable selection criteria for focal therapy (FT) are crucial to achieve success in localized prostate cancer (PCa). OBJECTIVE: To develop a multivariable model that better delineates eligibility for FT and reduces undertreatment by predicting unfavorable disease at radical prostatectomy (RP). DESIGN, SETTING, AND PARTICIPANTS: Data were retrospectively collected from a prospective European multicenter cohort of 767 patients who underwent magnetic resonance imaging (MRI)-targeted and systematic biopsies followed by RP in eight referral centers between 2016 and 2021. The Imperial College of London eligibility criteria for FT were applied: (1) unifocal MRI lesion with Prostate Imaging-Reporting and Data System score of 3-5; (2) prostate-specific antigen (PSA) ≤20 ng/ml; (3) cT2-3a stage on MRI; and (4) International Society of Urological Pathology grade group (GG) 1 and ≥6 mm or GG 2-3. A total of 334 patients were included in the final analysis. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was unfavorable disease at RP, defined as GG ≥4, and/or lymph node invasion, and/or seminal vesicle invasion, and/or contralateral clinically significant PCa. Logistic regression was used to assess predictors of unfavorable disease. The performance of the models including clinical, MRI, and biopsy information was evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analysis. A coefficient-based nomogram was developed and internally validated. RESULTS AND LIMITATIONS: Overall, 43 patients (13%) had unfavorable disease on RP pathology. The model including PSA, clinical stage on digital rectal examination, and maximum lesion diameter on MRI had an AUC of 73% on internal validation and formed the basis of the nomogram. Addition of other MRI or biopsy information did not significantly improve the model performance. Using a cutoff of 25%, the proportion of patients eligible for FT was 89% at the cost of missing 30 patients (10%) with unfavorable disease. External validation is required before the nomogram can be used in clinical practice. CONCLUSIONS: We report the first nomogram that improves selection criteria for FT and limits the risk of undertreatment. PATIENT SUMMARY: We conducted a study to develop a better way of selecting patients for focal therapy for localized prostate cancer. A novel predictive tool was developed using the prostate-specific antigen (PSA) level measured before biopsy, tumor stage assessed via digital rectal examination, and lesion size on magnetic resonance imaging (MRI) scans. This tool improves the prediction of unfavorable disease and may reduce the risk of undertreatment of localized prostate cancer when using focal therapy.

Risk stratification for early biochemical recurrence of prostate cancer in the era of multiparametric magnetic resonance imagining-targeted biopsy.

BACKGROUND: Multiparametric magnetic resonance imaging (MRI) and MRI-targeted biopsy are nowadays recommended in the prostate cancer (PCa) diagnostic pathway. Ploussard and Mazzone have integrated these tools into novel risk classification systems predicting the risk of early biochemical recurrence (eBCR) in PCa patients who underwent radical prostatectomy (RP). We aimed to assess available risk classification systems and to define the best-performing. METHODS: Data on 1371 patients diagnosed by MRI-targeted biopsy and treated by RP between 2014 and 2022 at eight European tertiary referral centers were analyzed. Risk classifications systems included were the European Association of Urology (EAU) and National Comprehensive Cancer Network (NCCN) risk groups, the Cancer of the Prostate Risk Assessment (CAPRA) score, the International Staging Collaboration for Cancer of the Prostate (STAR-CAP) classification, the Ploussard and Mazzone models, and ISUP grade group. Kaplan-Meier analyses were used to compare eBCR among risk classification systems. Performance was assessed in terms of discrimination quantified using Harrell's c-index, calibration, and decision curve analysis (DCA). RESULTS: Overall, 152 (11%) patients had eBCR at a median follow-up of 31 months (interquartile range: 19-45). The 3-year eBCR-free survival rate was 91% (95% confidence interval [CI]: 89-93). For each risk classification system, a significant difference among survival probabilities was observed (log-rank test p < 0.05) except for NCCN classification (p = 0.06). The highest discrimination was obtained with the STAR-CAP classification (c-index 66%) compared to CAPRA score (63% vs. 66%, p = 0.2), ISUP grade group (62% vs. 66, p = 0.07), Ploussard (61% vs. 66%, p = 0.003) and Mazzone models (59% vs. 66%, p = 0.02), and EAU (57% vs. 66%, p < 0.001) and NCCN (57% vs. 66%, p < 0.001) risk groups. Risk classification systems demonstrated good calibration characteristics. At DCA, the CAPRA score showed the highest net benefit at a probability threshold of 9%-15%. CONCLUSIONS: The performance of risk classification systems using MRI and MRI-targeted information was less optimistic when tested in a contemporary set of patients. CAPRA score and STAR-CAP classification were the best-performing and should be preferred for treatment decision-making.

Optimizing multiparametric magnetic resonance imaging-targeted biopsy and prostate cancer grading accuracy.

PURPOSE: To assess the most efficient biopsy method to improve International Society of Urological Pathology (ISUP) grade group accuracy with final pathology of the radical prostatectomy (RP) specimen in the era of magnetic resonance imaging (MRI)-driven pathway. METHODS: A total of 753 patients diagnosed by transrectal MRI-targeted and systematic biopsies (namely "standard method"), treated by RP, between 2016 and 2021 were evaluated. Biopsy methods included MRI-targeted biopsy, side-specific systematic biopsies relative to index MRI lesion and combination of both. Number of MRI-targeted biopsy cores and positive cores needed per index MRI lesion were assessed. Multivariable analysis was performed to analyze predictive factors of upgrading using MRI targeted and ipsilateral systematic biopsies method. RESULTS: Overall, ISUP grade group accuracy varied among biopsy methods with upgrading rate of 35%, 49%, 27%, and 24% for MRI targeted, systematic, MRI targeted and ipsilateral systematic biopsies and standard methods, respectively (p < 0.001). A minimum of two positive MRI-targeted biopsies cores per index MRI lesion were required when testing MRI targeted and ipsilateral systematic biopsies method to reach equivalent accuracy compared to standard method. Omitting contralateral systematic biopsies spared an average of 5.9 cores per patient. At multivariable analysis, only the number of positive MRI-targeted biopsy cores per index MRI lesion was predictive of upgrading. CONCLUSION: MRI targeted and ipsilateral systematic biopsies allowed an accurate definition of ISUP grade group and appears to be an interesting alternative when compared with standard method, reducing total number of biopsy cores needed.

Expanding Active Surveillance Criteria for Low- and Intermediate-risk Prostate Cancer: Can We Accurately Predict the Risk of Misclassification for Patients Diagnosed by Multiparametric Magnetic Resonance Imaging-targeted Biopsy?

Models predicting the risk of adverse pathology (ie, International Society of Urological Pathology [ISUP] grade group ≥3, pT3, and/or pN1) among patients operated by radical prostatectomy (RP) have been proposed to expand active surveillance (AS) inclusion criteria. We aimed to test these models in a set of 1062 low-risk and favorable intermediate-risk prostate cancer (PCa) patients diagnosed by multiparametric magnetic resonance imaging (MRI) and MRI-targeted biopsy. We hypothesized that the inclusion of radiological features into a novel model would improve patient selection. Performance was assessed using discrimination, calibration, and decision curve analysis (DCA). Available models were characterized by poor discrimination (areas under the receiver operating characteristic curve [AUCs] of 59% and 60%), underestimation of predicted risk on calibration plots, and a small amount of net benefit against a probability threshold of 40-50% at the DCA. The development of a novel model slightly improved discrimination (AUC of 63% vs 59%, p = 0.001, and 63% vs 60%, p = 0.07) and net benefit against threshold probabilities of ≥30%. This first multicenter study demonstrated the poor performance of models predicting adverse pathology and that implementation of MRI and MRI-targeted biopsy in this setting was not associated with a clear improvement in patient selection. Patients harboring low-risk or favorable intermediate-risk PCa and candidates for RP cannot be referred accurately to an AS program without a non-negligible risk of misclassification. PATIENT SUMMARY: We tested prediction models that could expand the selection of prostate cancer patients for active surveillance. Models were inaccurate and associated with a high risk of misclassification despite the implementation of multiparametric magnetic resonance imaging and targeted biopsies.

External Validation of Models for Prediction of Side-specific Extracapsular Extension in Prostate Cancer Patients Undergoing Radical Prostatectomy.

BACKGROUND: Predicting the risk of side-specific extracapsular extension (ECE) is essential for planning nerve-sparing radical prostatectomy (RP) in patients with prostate cancer (PCa). OBJECTIVE: To externally validate available models for prediction of ECE. DESIGN, SETTING, AND PARTICIPANTS: Sixteen models were assessed in a cohort of 737 consecutive PCa patients diagnosed via multiparametric magnetic resonance imaging (MRI)-targeted and systematic biopsies and treated with RP between January 2016 and November 2021 at eight referral centers. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Model performance was evaluated in terms of discrimination using area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analysis (DCA). RESULTS AND LIMITATIONS: Overall, ECE was identified in 308/1474 (21%) prostatic lobes. Prostatic lobes with ECE had higher side-specific clinical stage on digital rectal examination and MRI, number of positive biopsy cores, and International Society of Urological Pathology grade group in comparison to those without ECE (all p < 0.0001). Less optimistic performance was observed in comparison to previous published studies, although the models described by Pak, Patel, Martini, and Soeterik achieved the highest accuracy (AUC ranging from 0.73 to 0.77), adequate calibration for a probability threshold <40%, and the highest net benefit for a probability threshold >8% on DCA. Inclusion of MRI-targeted biopsy data and MRI information in models improved patient selection and clinical usefulness. Using model-derived cutoffs suggested by their authors, approximately 15% of positive surgical margins could have been avoided. Some available models were not included because of missing data, which constitutes a limitation of the study. CONCLUSIONS: We report an external validation of models predicting ECE and identified the four with the best performance. These models should be applied for preoperative planning and patient counseling. PATIENT SUMMARY: We validated several tools for predicting extension of prostate cancer outside the prostate gland. These tools can improve patient selection for surgery that spares nerves affecting recovery of sexual potency after removal of the prostate. They could potentially reduce the risk of finding cancer cells at the edge of specimens taken for pathology, a finding that suggests that not all of the cancer has been removed.

Radiotherapy to the Primary Tumor: The First Step of a Tailored Therapy in Metastatic Prostate Cancer.

Prostate cancer is the first most frequent cancer in men worldwide, with over 250,000 estimated new cases diagnosed in 2021 [...].

Quality of Life and Psychological Distress among Patients with Small Renal Masses.

Background: Quality of life (QoL) and psychological distress represent an important aspect of the daily life of cancer patients. The aim of this systematic review was to critically analyze available literature regarding QoL and psychological distress in patients with small renal masses (SRMs). (2) Methods: A systematic search of EMBASE, PUBMED and American Psychological Association (APA-net) was performed on 30 April 2022. Studies were considered eligible if they included patients with SRMs, had a prospective or retrospective design, included at least 10 patients, were published in the last 20 years, and assessed the QoL or psychological distress in patients that underwent active surveillance (AS) in comparison to those that underwent ablation/surgery treatments. (3) Results: The patients that underwent AS were statistically significantly older, with smaller renal masses than those that underwent surgery/ablation. A study showed a significant reduction in total scores of Short Form-12 (SF-12) among AS patients when compared to partial nephrectomy (PN) patients at enrollment (95.0 ± 15.8 vs. 99.1 ± 13.9), 2 years (91.0 ± 16.4 vs. 100.3 ± 14.3), and at 3 years (92.9 ± 15.9 vs. 100.3 ± 14.3), p < 0.05, respectively. That was mainly due to lower physical health scores. On the other hand, another study showed that AS patients with a biopsy-proven malignant tumor had a worse psychological distress sub-score (PDSS) compared to patients treated with surgery/ablation after biopsy. (4) Conclusions: It seems that there is an influence on QoL and psychological distress while on AS of SMRs. However, due to the low amount of available data, the impact of AS or active treatment on QoL or psychological distress of patients with small renal masses warrants further investigation.

Sexual and ejaculatory function after holmium laser enucleation of the prostate and bipolar transurethral enucleation of the prostate: a single-center experience.

Currently available surgical treatments for Lower Urinary Tract Symptoms (LUTS) due to Benign Prostatic Obstruction (BPO) are associated with an increased risk of sexual dysfunction. The aim of our study is to compare sexual and ejaculatory function after Holmium Laser Enucleation of the Prostate (HoLEP) and Bipolar Transurethral Enucleation of the Prostate (B-TUEP). We performed a retrospective analysis of data prospectively collected from 62 (44.9%) and 76 (55.1%) patients who underwent HoLEP and B-TUEP, respectively. Erectile function and ejaculation characteristics were assessed with the International Index of Erectile Function-Erectile Function (IIEF-EF) domain and the Male Sexual Health Questionnaire-Ejaculatory function (MSHQ-EJ) questionnaires. Our study recorded no change in erectile function and no significant difference in rates of preserved antegrade ejaculation after both surgeries. One month after surgery, rates of physical pain/discomfort and perceived decreased physical pleasure during ejaculation were higher in HoLEP than B-TUEP patients (all p < 0.03). Moreover, HoLEP patients were more bothered by their ejaculatory difficulties than B-TUEP men (p = 0.03). At 3- and 12-months follow-up, all ejaculation-related differences disappeared. In conclusion, both procedures are valid alternatives for BPO treatment as they offer comparable urinary and sexual outcomes in the long term. However, in the first month after surgery, HoLEP patients present with more ejaculatory difficulties.

Development of a Novel Clinical and Radiologic Risk Score to Predict Septic Complications After Urinary Decompression in Patients with Obstructive Uropathy.

Background: Well-defined clinical predictors of sepsis after upper tract drainage for obstructive uropathy are lacking. The study aim is to develop a data-driven score to predict risk of sepsis after decompression of the upper urinary tract. Materials and Methods: Complete clinical and radiologic data from 271 patients entering the emergency department for obstructive uropathy and submitted to stent/nephrostomy tube decompression were evaluated. The Charlson Comorbidity Index (CCI) was used to score comorbidities. The definition of sepsis was an increase in ≥2 Sequential Organ Failure Assessment points (or a postoperative persistently elevated score +1 additional increase) and documented blood or urine cultures. Descriptive statistics and stepwise multivariable logistic regression modeling with receiver operating characteristic analysis were performed to obtain a composite risk score to predict the risk of sepsis after surgery. This study was approved by our local Ethics Commitee (Prot. 25508). Results: Fifty-five (20.3%) patients developed sepsis. At multivariable analysis, CCI ≥2 (odds ratio [OR] 3.10; 95% confidence interval [CI] 1.36-7.04), maximum body temperature ≥38°C (OR 4.35; 95% CI 1.89-9.44), grade III-IV hydronephrosis (OR 2.37; 95% CI 1.10-4.98), HU of the dilated collecting system ≥7.0 (OR 4.47; 95% CI 2.03-9.81), white blood cells ≥15 × 103/mmc (OR 2.77; 95% CI 1.24-6.19), and C-reactive protein ≥10 (OR 3.27; 95% CI 1.41-7.56) were independently associated with sepsis. The positive predictive value of a true sepsis increased incrementally as a function of number of positive variables, ranging from 1.6% to 100.0% among patients with 1 and 6 positive variables, respectively. Conclusion: Our risk score identifies accurately patients with an increased risk of sepsis after urinary decompression for obstructive uropathy, hence improving clinical management.

Cost analysis between mini-percutaneous nephrolithotomy with and without vacuum-assisted access sheath.

PURPOSE: To perform a cost analysis between vacuum-assisted percutaneous nephrolithotomy (vmPCNL) and minimally invasive PCNL (MIP) and explore potential predictors of costs associated with the procedures. METHODS: We analyzed data from 225 patients who underwent vmPCNL or MIP at a single tertiary referral academic center between January 2016 and December 2020. We collected patients' demographics, peri-and postoperative data and detailed expense records. After propensity score matching, 108 (66.7%) vmPCNL and 54 (33.3%) MIP procedures were analyzed. Descriptive statistics assessed differences in clinical and operative parameters. Univariable and multivariable linear regression models tested the association between clinical variables and costs. RESULTS: Operative time (OT) was shorter for vmPCNL, and the use of additional instruments to complete litholapaxy was more frequent in MIP (all p ≤ 0.01). Length of stay (LOS) was longer for MIP patients (p = 0.03) and the stone-free (SF) rate was higher after vmPCNL (p = 0.04). The overall instrumentation cost was higher for vmPCNL (p < 0.001), but total procedural costs were equivalent (p = 0.9). However, the overall cost for the hospitalization was higher for MIP than vmPCNL (p = 0.01). Univariable linear regression revealed that patient's comorbidities, OT, any postoperative complication and LOS were associated with hospitalization costs (all p < 0.001). Multivariable linear regression analysis revealed that LOS and OT were associated with hospitalization costs (all p < 0.001), after accounting for vmPCNL procedure, patients' comorbidities, and complications. CONCLUSION: vmPCNL may represent a valid option due to clinical and economic benefits. Shorter OT, the lower need for disposable equipment and the lower complication rate reduced procedural and hospitalization costs.

The Effect of CO2 Pressure and Flow Variation on Carbon Particles Spread During Pneumoperitoneum: An Experimental Study.

Background: A correlation between atypical recurrences and minimally-invasive surgery has been suggested in case of urothelial cancer; however, few data are available on the role of pneumoperitoneum in terms of gas flow and intra-abdominal pressure. The objective of the study is to analyze the impact of CO2 pneumoperitoneum variation on an inert material as surrogate of neoplastic cells. Material and Methods: We designed an experimental model mimicking pneumoperitoneum in three settings: sealed flow (no leakage), pulsatile flow (alternating efflux and influx), and continuous flow (AirSeal® insufflator). Each experiment was characterized by a predetermined gas flow and pressure, trocar distance, and position from the particles. Hounsfield density (HD) variation in the areas of interest was measured as index of graphite powder dispersion. A Linear Regression Model was used to measure the correlation between modifiable variables and HD. Results: HD was lower in the pulsatile compared to both the sealed and continuous flows (p < 0.03). On multivariate analysis for sealed setting, flow and total gas liters delivered (i.e., gas leakage) were inversely and independently related to HD (all p < 0.03). In pulsatile setting, trocar position, trocar distance, and gas flow independently predicted HD (all p < 0.03). In continuous setting, gas pressure was directly and independently related to HD (p = 0.004) due to decreased pneumoperitoneum stability and increased CO2 liters delivered. In case of inflow trocar positioned laterally to the particles, low flow (1 L/min), or low pressure (8 mmHg), HD values recorded in the three settings were all overlapping (all p > 0.05). Conclusions: Flow and pressure setting, inflow trocar distance and contiguity from the tumor, and pneumoperitoneum stability may be all crucial components in minimally invasive surgery. In vivo, these variables should be considered as potential risk factors for tumor cells spread within the abdominal cavity. Clinical Trial Registration number: NCT01740011.

The Matryoshka technique in percutaneous nephrolithotomy.

OBJECTIVE: Miniaturized percutaneous nephrolithotomy (PCNL) reduces the risk of haemorrhagic complications, but the limited field of work represents a drawback. To obtain the best outcomes, the percutaneous access size should be intraoperatively tailored. Our purpose is to describe the indications and the procedural steps of the Matryoshka technique and to report its clinical outcomes. MATERIALS AND METHODS: We performed a retrospective analysis of the data from consecutive Matryoshka PCNL procedures from October 2016 to January 2018. Collected data included patients' history, stone characteristics, intra- and post-operative items, stone clearance and need for retreatment. The main indication to the Matryoshka technique is the inability to securely position a guidewire due to an obstruction or narrowness in the pyelocalyceal system. This technique begins by puncturing the calyx hosting the stone and advancing a hydrophilic guidewire through the needle. If the guidewire cannot proceed beyond the stone, the Matryoshka technique is employed for tract stabilization. The tract is carefully dilated with small-bore instruments and a cautious lithotripsy is performed to create enough space to introduce the guidewire beyond the stone under visual control. Once the access has been stabilized the surgeon can upsize the tract to the optimum to complete the procedure. Additionally, the technique can be employed when an intraoperative reassessment induces the surgeon to further dilate the tract to quicken the procedure. RESULTS: Sixteen patients were included, with a median stone volume of 3.49 cm3. Median operative time was 112 minutes. Three Clavien I-II (postoperative fever) and one Clavien IIIB (colon perforation) complications were reported. No blood transfusions were recorded. Three patients underwent scheduled retreatment as part of a multistep procedure. Out of the remaining 13 patients, 10 (76.9%) obtained a complete stone clearance. CONCLUSIONS: The Matryoshka technique helps the urologist to obtain a secure percutaneous access and makes PCNL flexible and progressive, potentially minimizing the risk of access-related complications.

Bipolar Transurethral Enucleation of the Prostate: Is it a size-independent endoscopic treatment option for symptomatic benign prostatic hyperplasia?

BACKGROUND: Bipolar Transurethral Enucleation of the Prostate (B-TUEP) is recommended as a first-choice treatment for benign prostatic obstruction in prostates >80 ml. Differently, B-TUEP is only considered as an alternative option after TURP for smaller prostates (30-80 ml). The aim of our study is to assess the relation between prostate size and surgical outcomes after B-TUEP. METHODS: We performed a retrospective analysis of data collected from 172 patients submitted to B-TUEP. Patients were segregated according to tertiles of prostate volume (PV) (≤60 ml, 61-110 ml, >110 ml). For each group we evaluated enucleation efficacy (enucleated weight/enucleation time), complication rates, urinary and sexual function parameters. Functional and sexual parameters were compared between groups at baseline, 1 and 3 months follow up. Descriptive statistics and linear and logistic regression models tested the association between PV and postoperative complications/outcomes. RESULTS: Operative time and weight of enucleated adenomas increased along with prostate volumes (all p≤0.01). Enucleation efficacy was higher in men with PV >110 ml compared to other groups (p≤0.001). Length of hospital stay, catheterization time and rates of postoperative complications, such as transfusion and clot evacuation rates and bladder neck/urethral strictures, were comparable between groups. Urinary symptoms improved at 1-and 3-months in each group as compared to baseline evaluation (all p<0.01) but they did not differ according to PV. In each group maximum urinary flow and post-void residual volume significantly improved at 3 months compared to baseline (all p≤0.01), without differences according to PV. Sexual symptoms were similar between groups at each follow up assessment. At multivariable linear and logistic regression analysis, prostate volume was not associated with postoperative functional outcomes and complications. Conversely, patient's comorbid status and antiplatelet/anticoagulation use were independently associated with postoperative complications. CONCLUSION: According to our findings, B-TUEP should be considered a "size independent procedure" as it can provide symptom relief in men with prostates of all sizes with the same efficacy and safety profile.

Micropapillary Bladder Cancer Metastatic to the Breast: A Case Report and Brief Literature Review.

BACKGROUND: Bladder cancer (BC) usually metastasizes to the lymph nodes, bone, lung, liver and peritoneum, but rarely in the breast. CASE REPORT: We present a case of a 66-year-old female diagnosed with a massive bladder tumor, who presented a right mammary nodule after neo-adjuvant chemotherapy. A biopsy of the nodule did not permit a definite diagnosis of metastatic spread, which was confirmed by excision of the nodule. In the literature, we found only 7 other similar cases of BC metastasis to the breast. Currently, a non-invasive method for differentiating a breast metastasis from primary cancer is lacking, although there are some clinical and radiological aspects that may help the diagnosis. Histological examination provides diagnostic certainty. CONCLUSION: Breast metastases from BC are unusual and consequently difficult to identify without non-invasive tools. Clinical history and histological study play a pivotal role in determining the correct diagnosis.

Clinical Comparison of Mini-Percutaneous Nephrolithotomy with Vacuum Cleaner Effect or with a Vacuum-Assisted Access Sheath: A Single-Center Experience.

Purpose: To compare outcomes of two different miniaturized percutaneous nephrolithotomy (PCNL) techniques: minimally invasive PCNL (MIP) with the vacuum cleaner effect and vacuum-assisted mini-PCNL (vmPCNL). Materials and Methods: Data from 104 (66.7%) patients who underwent vmPCNL and 52 (33.3%) patients who underwent MIP at a single tertiary referral academic center between January 2016 and December 2019 were analyzed. Patient demographics and peri- and postoperative data were recorded, and propensity score matching was performed. Descriptive statistics and linear regression models were used to identify variables associated with operative time (OT) and patient effective dose. Logistic regression analyses were used to identify factors associated with infectious complications and stone-free (SF) status. Results: Patient demographics and stone characteristics were comparable between groups. vmPCNL was associated with shorter OT (p < 0.001), fluoroscopy time, and patient effective dose (4.2 mSv vs 7.9 mSv; p < 0.001). A higher rate of infectious complications was found in the MIP group (25.0% vs 7.7%, p < 0.01). Linear regression analysis showed that stone volume, multiple stones, and MIP procedure (all p values ≤0.02) were associated with longer OT. Similarly, OT and the MIP procedure (p ≤ 0.02) were associated with higher patient effective dose. Logistic regression analysis revealed that the stone volume, positive preoperative bladder urine culture, and MIP procedure (all p values ≤0.02) were associated with postoperative infectious complications. vmPCNL was not associated with the SF rate. Conclusions: Mini-PCNL performed with continuous active suction is associated with lower rates of infectious complications, shorter OT, and lower patient effective dose than MIP.

How the COVID-19 Wave Changed Emergency Urology: Results From an Academic Tertiary Referral Hospital in the Epicentre of the Italian Red Zone.

OBJECTIVE: To quantify and characterize the burden of urological patients admitted to emergency department (ED) in Lombardy during Italian COVID-19 outbreak, comparing it to a reference population from 2019. METHODS: We retrospectively analysed all consecutive admissions to ED from 1 January to 9 April in both 2019 and 2020. According to the ED discharge ICD-9-CM code, patients were grouped in urological and respiratory patients. We evaluated the type of access (self-presented/ambulance), discharge priority code, ED discharge (hospitalization, home), need for urological consultation or urgent surgery. RESULTS: The number of urological diagnoses in ED was inversely associated to COVID-19 diagnoses (95% confidence interval -0.41/-0.19; Beta = -0.8; P < .0001). The average access per day was significantly lower after 10 March 2020 (1.5 ± 1.1 vs 6.5 ± 2.6; P < .0001), compared to reference period. From 11 March 2020, the inappropriate admissions to ED were reduced (10/45 vs 96/195; P = .001). Consequently, the patients admitted were generally more demanding, requiring a higher rate of urgent surgeries (4/45 vs 4/195; P = .02). This reflected in an increase of the hospitalization rate from 12.7% to 17.8% (Beta = 0.88; P < .0001) during 2020. CONCLUSION: Urological admissions to ED during lockdown differed from the same period of 2019 both qualitatively and quantitatively. The spectrum of patients seems to be relatively more critical, often requiring an urgent management. These patients may represent a challenge due to the difficult circumstances caused by the pandemic.