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Background: Following our hypothesis that oxidative stress might play a primary role in renal ischemia/reperfusion injury (RIRI), we investigated if ethyl pyruvate (EPy) with potent antioxidant activity might prevent or alleviate RIRI induced in rats. Methods: Sprague-Dawley rats were randomly divided into four groups: (A) Sham, (B) renal ischemia/reperfusion (RIR), (C) RIR with EPy supplement (RIR+EPy), and (D) RIR with Mann supplement (RIR+Mann). Mannitol (Mann), a preoperative agent being clinically used, was tested for comparison with EPy. Rats were subjected to 40-min ischemia, followed by 24-h reperfusion. Either EPy or Mann was given to rats 30 min prior to ischemia and immediately before the reperfusion period. Results: The RIR and RIR+Mann groups showed palpable kidney injuries with the ~5-fold elevated blood urea nitrogen (BUN) and creatinine (Cr) levels, indicating renal dysfunction. However, the kidneys in the RIR+EPy group appeared merely normal (similar to the Sham’s) with the basal BUN/Cr levels, indicating normal renal function. No effects on histology, BUN or Cr were yet seen with Mann. Moreover, specific kidney injury markers were up-regulated and oxidative stress was also ~2.1-fold severer in the RIR group, whereas little changes in those markers and oxidative stress were seen with EPy supplement (RIR+EPy). Conclusions: Although oxidative stress feasibly plays a key role in RIRI, EPy with antioxidant activity is capable of protecting the kidneys from such an assault. Thus, EPy (not Mann) should be considered as an effective perioperative renoprotective agent that could be used clinically.

Let $${{\mathfrak {S}}}_n$$ be the nth symmetric group. Given a set of permutations $$\Pi $$, we denote by $${{\mathfrak {S}}}_n(\Pi )$$ the set of permutations in $${{\mathfrak {S}}}_n$$ which avoid $$\Pi $$ in the sense of pattern avoidance. Consider the generating function $$Q_n(\Pi )=\sum _\sigma F_{{{\,\mathrm{Des}\,}}\sigma }$$ where the sum is over all $$\sigma \in {{\mathfrak {S}}}_n(\Pi )$$ and $$F_{{{\,\mathrm{Des}\,}}\sigma }$$ is the fundamental quasisymmetric function corresponding to the descent set of $$\sigma $$. Hamaker, Pawlowski, and Sagan introduced $$Q_n(\Pi )$$ and studied its properties, in particular, finding criteria for when this quasisymmetric function is symmetric or even Schur nonnegative for all $$n\ge 0$$. The purpose of this paper is to continue their investigation by answering some of their questions, proving one of their conjectures, as well as considering other natural questions about $$Q_n(\Pi )$$. In particular, we look at $$\Pi $$ of small cardinality, superstandard hooks, partial shuffles, Knuth classes, and a stability property.

Objectives To develop a preoperative nomogram that would predict the risk of a postoperative complication for pheochromocytoma patients undergoing adrenalectomy using an international database. Methods We retrospectively analyzed preoperative variables and postoperative outcomes in patients who underwent adrenalectomy for pheochromocytoma in three institutions from 2000 to 2017. Internal validation of a generated nomogram was carried out with receiver operating characteristics, calibration plots, and decision curve analyses. Results A total of 153 patients who had undergone 166 adrenalectomies were included in the study. Overall, post-adrenalectomy complications were seen in 30% of patients, whereas 9.6% of patients sustained a Clavien ≥3a complication. Independent predictors of a complication were a history of hypertension, body mass index, tumor size, and Charlson Comorbidity Index score. On internal validation, the multivariable model generated a nomogram that predicted a postoperative complication or clinically hemodynamic event with an area under the curve of 0.86, showed good calibration and had an overall net benefit. Conclusions An internally validated nomogram combining body mass index, Charlson Comorbidity Index score and tumor size can predict the probability of a post-adrenalectomy complication in those with and without hypertension. The model, the first of its kind in pheochromocytoma surgery, identifies patients at risk of a postoperative complication at the time of their presentation with pheochromocytoma.

Background The use of 12-core systematic prostate biopsy is associated with diagnostic inaccuracy that contributes to both overdiagnosis and underdiagnosis of prostate cancer. Biopsies per...

While multiple studies have demonstrated that minimally invasive surgical (MIS) techniques are a safe and efficacious approach to adrenalectomy for pheochromocytomas (PC), these studies have only been small comparative studies. The aim of this multi-institutional study is to compare perioperative outcomes between open and MIS, stratified by robotic and conventional laparoscopic, techniques in the surgical management of PC. We retrospectively evaluated patients who underwent adrenalectomy for PCs from 2000 to 2017 at three different institutions. Clinical, perioperative, and pathologic parameters were analyzed using t test, Chi square, and Fisher exact statistical measures. Of the 156 adrenalectomy cases performed, 26 (16.7%) were with an open approach and 130 (83.3%) using MIS techniques. Of the MIS procedures, 41 (31.5%) were performed robotically and 89 (68.5%) performed laparoscopically without robotic assistance. Demographic and clinical parameters were similar between the open and MIS groups. Patients, who underwent MIS procedure had a lower complication rate (p = 0.04), shorter hospitalization (p = 0.02), shorter operative time (p < 0.001), and less blood loss (p = 0.002) than those who underwent open surgical resection. Conventional laparoscopic and robotic operative approaches resulted in similar complication rates, length of hospitalization, and blood loss. Our study is one of the largest cohorts comparing the perioperative outcomes between conventional laparoscopic and robotic adrenalectomies in patients with PC. Our results support that MIS techniques have potentially lower morbidity compared to open techniques, while laparoscopic and robotic approaches have similar perioperative outcomes.

Objective Increased computational power and improved visualization hardware have generated more opportunities for virtual reality (VR) applications in healthcare. In this study, we test the feasibility of a VR-assisted surgical navigation system for robotic-assisted radical prostatectomy. Material and methods The prostate, all magnetic resonance imaging (MRI) visible tumors, and important anatomic structures like the neurovascular bundles, seminal vesicles, bladder, and rectum were contoured on a multiparametric MRI using an in-house segmentation software. Three-dimensional (3-D) VR models were rendered and evaluated in a side room of the operating room. While interacting with the VR platform, a real-time stereo video capture of the in situ prostate was obtained to render a second 3-D model. The MRI-based model was then overlaid on the real-time model by using an automated alignment algorithm. Results Ten patients were included in this study. All MRI-based VR models were examined by surgeons immediately prior to surgery and at important steps where visualization of the tumors and their proximity to surrounding anatomic structures were critical. This was mainly during the preparation of the prostatic pedicles, neurovascular plexus, the apex, and bladder neck. All participants found the system useful, especially for tumors with locally aggressive growth patterns. For small and centrally located tumors, the system was not considered beneficial due to lack of integration into the robotic console. A fully integrated system with real-time overlays within the robotic stereo viewer was found to be the ideal scenario. Conclusion We deployed a preliminary VR-assisted surgical navigation tool for robotic-assisted radical prostatectomies.

OBJECTIVES To determine the rate of Gleason Grade Group (GGG) upgrading in African-American (AA) men with a prior diagnosis of low-grade prostate cancer (GGG 1 or GGG 2) on 12-core systematic biopsy (SB) after multiparametric magnetic resonance imaging (mpMRI) and fusion biopsy (FB); and whether AA men who continued active surveillance (AS) after mpMRI and FB fared differently than a predominantly Caucasian (non-AA) population. PATIENTS AND METHODS A database of men who had undergone mpMRI and FB was queried to determine rates of upgrading by FB amongst men deemed to be AS candidates based on SB prior to referral. After FB, Kaplan-Meier curves were generated for AA men and non-AA men who then elected AS. The time to GGG upgrading and time continuing AS were compared using the log-rank test. RESULTS AA men referred with GGG 1 disease on previous SB were upgraded to GGG ≥3 by FB more often than non-AA men, 22.2% vs 12.7% (P = 0.01). A total of 32 AA men and 258 non-AA men then continued AS, with a median (interquartile range) follow-up of 39.19 (24.24-56.41) months. The median time to progression was 59.7 and 60.5 months, respectively (P = 0.26). The median time continuing AS was 61.9 months and not reached, respectively (P = 0.80). CONCLUSIONS AA men were more likely to be upgraded from GGG 1 on SB to GGG ≥3 on initial FB; however, AA and non-AA men on AS subsequently progressed at similar rates following mpMRI and FB. A greater tendency for SB to underestimate tumour grade in AA men may explain prior studies that have shown AA men to be at higher risk of progression during AS.

INTRODUCTION AND OBJECTIVE:Surgeons rely on 2D computed tomography (CT) scans for preoperative planning. IRIS is an interactive 3D virtual adjunct for surgical planning that includes features such ...

INTRODUCTION AND OBJECTIVE:Magnetic resonance imaging (MRI) offers high spatial resolution imaging of the prostate. Diagnostic radiologists annotate and describe the location of lesions in the imag...

Objective To evaluate the use of 3D computed aided designs and 3D-printed models as pre-operative planning tools for urologists, in addition to radiologist interpreted mp-MRIS, prior to radical prostatectomy procedures. Methods Ten patients with biopsy-positive lesions detected on mp-MRI were retrospectively selected. Radiologists identified lesion locations using a Prostate Imaging-Reporting and Data System (PI-RADS) map and segmented the prostate, lesion(s), and surrounding anatomy to create 3D-CADs and 3D-printed models for each patient. 6 uro-oncologists randomly reviewed three modalities (mp-MRI, 3D-CAD, and 3D-printed models) for each patient and identified lesion locations which were graded for accuracy against the radiologists’ answers. Questionnaires assessed decision confidence, ease-of-interpretation, and usefulness for preoperative planning for each modality. Results Using 3D-CADs and 3D-printed models compared to mp-MRI, urologists were 2.4x and 2.8x more accurate at identifying the lesion(s), 2.7x and 3.2x faster, 1.6x and 1.63x more confident, and reported it was 1.6x and 1.7x easier to interpret. 3D-CADs and 3D-printed models were reported significantly more useful for overall pre-operative planning, identifying lesion location(s), determining degree of nerve sparing, obtaining negative margins, and patient counseling. Sub-analysis showed 3D-printed models demonstrated significant improvements in ease-of-interpretation, speed, usefulness for obtaining negative margins, and patient counseling compared to 3D-CADs. Conclusion 3D-CADs and 3D-printed models are useful adjuncts to mp-MRI in providing urologists with more practical, accurate, and efficient pre-operative planning.

IRISSeven surgeons randomly reviewed IRIS and CT images of 9 patients with renal masses [5 high complexity (RENAL score ≥ 8), 4 low complexity (≤ 7)]. Surgeons answered a series of questions regarding patient anatomy, perceived difficulty (/100), confidence (/100), and surgical plan. Eye tracking metrics (mean pupil diameter, number of fixations, and gaze duration) were collected.Surgeons spent significantly less time interpreting data from IRIS than CT scans (- 67.1 s, p 0.01) and had higher inter-rater agreement of surgical approach after viewing IRIS (α = 0.16-0.34). After viewing IRIS, surgical plans although not statistically significant demonstrated a greater tendency towards a more selective ischemia approaches which positively correlated with improved identification of vascular anatomy. Planned surgical approach changed in 22/59 of the cases. Compared to viewing the CT scan, left and right mean pupil diameter and number/duration of fixations were significantly lower when using IRIS (p 0.01, p 0.01, p = 0.42, p 0.01, respectively), indicating interpreting information from IRIS required less mental effort despite under-utilizing its interactive features.Surgeons extrapolated more detailed information in less time with less mental effort using IRIS than CT scans and proposed surgical approaches with potential to enhanced surgical outcomes.

Background While magnetic resonance imaging (MRI)-targeted biopsy (TBx) results in better prostate cancer (PCa) detection relative to systematic biopsy (SBx), the combination of both methods increases clinically significant PCa detection relative to either Bx method alone. However, combined Bx subjects patients to higher number of Bx cores and greater detection of clinically insignificant PCa. Objective To determine if prebiopsy prostate MRI can identify men who could forgo combined Bx without a substantial risk of missing clinically significant PCa (csPC). Design, setting, and participants Men with MRI-visible prostate lesions underwent combined TBx plus SBx. Outcome measurements and statistical analysis The primary outcomes were detection rates for grade group (GG) ≥2 and GG ≥3 PCa by TBx and SBx, stratified by Prostate Imaging-Reporting and Data System (PI-RADS) score. Results and limitations Among PI-RADS 5 cases, nearly all csPCs were detected by TBx, as adding SBx resulted in detection of only 2.5% more GG ≥2 cancers. Among PI-RADS 3–4 cases, however, SBx addition resulted in detection of substantially more csPCs than TBx alone (8% vs 7.5%). Conversely, TBx added little to detection of csPC among men with PI-RADS 2 lesions (2%) relative to SBx (7.8%). Conclusions While combined Bx increases the detection of csPC among men with MRI-visible prostate lesions, this benefit was largely restricted to PI-RADS 3–4 lesions. Using a strategy of TBx only for PI-RADS 5 and combined Bx only for PI-RADS 3–4 would avoid excess biopsies for men with PI-RADS 5 lesions while resulting in a low risk of missing csPC (1%). Patient summary Our study investigated an optimized strategy to diagnose aggressive prostate cancer in men with an abnormal prostate MRI (magnetic resonance imaging) scan while minimizing the risk of excess biopsies. We used a scoring system for MRI scan images called PI-RADS. The results show that MRI-targeted biopsies alone could be used for men with a PI-RADS score of 5, while men with a PI-RADS score of 3 or 4 would benefit from a combination of MRI-targeted biopsy and systematic biopsy. This trial is registered at ClinicalTrials.gov as NCT00102544.

Conventional staging for prostate cancer (PCa) is performed for men diagnosed with unfavorable-intermediate or higher risk disease. Computed tomography (CT) of the abdomen and pelvis and whole body bone scan remains the standard of care for the detection of visceral, nodal, and bone metastasis. The implementation of the 2012 United States Preventive Services Task Force recommendation against routine prostate specific antigen (PSA) screening resulted in a rise of metastatic PCa at the time of diagnosis, emphasizing the importance of effective imaging modalities for evaluating metastatic disease. CT plays a major role in clinical staging at the time of PCa diagnosis, but multi-parametric magnetic resonance imaging (MRI) is now integrated into many prostate biopsy protocols for the detection of primary PCa, and may be a surrogate for CT for nodal staging. Current guidelines incorporate both CT and MRI as appropriate cross-sectional imaging modalities for the identification of nodal metastasis in indicated patients. There is an ongoing debate about the utility of traditional cross-sectional imaging modalities as well as advanced imaging modalities in detection of both organ-confined PCa detection and nodal involvement.