Dusk-Dawn Asymmetries in SuperDARN Convection Maps.

The Super Dual Auroral Radar Network (SuperDARN) is a collection of radars built to study ionospheric convection. We use a 7-year archive of SuperDARN convection maps, processed in 3 different ways, to build a statistical understanding of dusk-dawn asymmetries in the convection patterns. We find that the data set processing alone can introduce a bias which manifests itself in dusk-dawn asymmetries. We find that the solar wind clock angle affects the balance in the strength of the convection cells. We further find that the location of the positive potential foci is most likely observed at latitudes of 78° for long periods (>300 min) of southward interplanetary magnetic field (IMF), as opposed to 74° for short periods (<20 min) of steady IMF. For long steady dawnward IMF the median is also at 78°. For long steady periods of duskward IMF, the positive potential foci tends to be at lower latitudes than the negative potential and vice versa during dawnward IMF. For long periods of steady Northward IMF, the positive and negative cells can swap sides in the convection pattern. We find that they move from ∼0-9 MLT to 15 MLT or ∼15-23 MLT to 10 MLT, which reduces asymmetry in the average convection cell locations for Northward IMF. We also investigate the width of the region in which the convection returns to the dayside, the return flow width. Asymmetries in this are not obvious, until we select by solar wind conditions, when the return flow region is widest for the negative convection cell during Southward IMF.

Frailty predicts outcome of partial nephrectomy and guides treatment decision towards active surveillance and tumor ablation.

PURPOSE: To examine frailty and comorbidity as predictors of outcome of nephron sparing surgery (NSS) and as decision tools for identifying candidates for active surveillance (AS) or tumor ablation (TA). METHODS: Frailty and comorbidity were assessed using the modified frailty index of the Canadian Study of Health and Aging (11-CSHA) and the age-adjusted Charlson-Comorbidity Index (aaCCI) as well as albumin and the radiological skeletal-muscle-index (SMI) in a cohort of n = 447 patients with localized renal masses. Renal tumor anatomy was classified according to the RENAL nephrometry system. Regression analyses were performed to assess predictors of surgical outcome of patients undergoing NSS as well as to identify possible influencing factors of patients undergoing alternative therapies (AS/TA). RESULTS: Overall 409 patient underwent NSS while 38 received AS or TA. Patients undergoing TA/AS were more likely to be frail or comorbid compared to patients undergoing NSS (aaCCI: p < 0.001, 11-CSHA: p < 0.001). Gender and tumor complexity did not vary between patients of different treatment approach. 11-CSHA and aaCCI were identified as independent predictors of major postoperative complications (11-CSHA ≥ 0.27: OR = 3.6, p = 0.001) and hospital re-admission (aaCCI ≥ 6: OR = 4.93, p = 0.003) in the NSS cohort. No impact was found for albumin levels and SMI. An aaCCI > 6 and/or 11-CSHA ≥ 0.27 (OR = 9.19, p < 0.001), a solitary kidney (OR = 5.43, p = 0.005) and hypoalbuminemia (OR = 4.6, p = 0.009), but not tumor complexity, were decisive factors to undergo AS or TA rather than NSS. CONCLUSION: In patients with localized renal masses, frailty and comorbidity indices can be useful to predict surgical outcome and support decision-making towards AS or TA.

Prospective geriatric assessment for perioperative risk stratification in partial nephrectomy.

PURPOSE: Comorbidities and frailty are determinants of surgical outcome. The aim of the study was to examine various measures of frailty and comorbidities in predicting postoperative outcome of partial nephrectomy (PN). METHODS: We prospectively analyzed the frailty and comorbidity status of 150 patients undergoing PN between 2015 and 2018. Primary endpoint was the occurrence of major postoperative complications (MPC) and secondary endpoints were the failure of Trifecta achievement and the need for hospital readmissions. For the transfer into clinical practice the most significant frailty parameters were summarized in a multi-dimensional test. RESULTS: Median age was 67 (33-93) years, 64.7% of the patients were male. Univariable regression analysis showed, that patients with increased frailty indices (Hopkins frailty score ≥2 (OR = 3.74, p = 0.005), Groningen frailty index ≥4 (OR = 2.85, p = 0.036)) are at higher risk to develop MPC. Furthermore, poor physical performance, such as a low handgrip strength or a Full-Tandem-Stand (FTS) < 10 s were associated with MPC (OR = 4.76, p = 0.014; OR = 4.48, p = 0.018) and Trifecta failure (OR = 3.60, p = 0.037, OR = 5.50, p = 0.010). Six measures were combined to the geriatric assessment in partial nephrectomy score (GAPN). A GAPN-score ≥3 proved to be a significant predictor for MPC (OR = 4.30, p = 0.029) and for Trifecta failure (OR = 0.20, p = 0.011) in multivariable regression analysis. CONCLUSION: The frailty status and comorbidities are important determinants of the postoperative course after PN. These parameters should be assessed preoperatively and included in the treatment planning, especially in light of available alternative therapies. In this context, the GAPN-score may be a suitable tool.

The comprehensive complication index (CCI): proposal of a new reporting standard for complications in major urological surgery.

PURPOSE: The comprehensive complication index (CCI) is a new tool for reporting the cumulative burden of postoperative complications on a continuous scale. This study validates the CCI for urological surgery and its benefits over the Clavien-Dindo-Classification (Clavien). MATERIAL AND METHODS: Data from a prospectively maintained data base of all consecutive patients at a university care-center was analyzed. Complications after radical cystectomy (RC), radical prostatectomy (RP), and partial nephrectomy (PN) were classified using the CCI and Clavien system. Differences in complications between the CCI and the Clavien were assessed and correlation analyses performed. Sample size calculations for hypothetical clinical trials were compared between CCI and Clavien to evaluate whether the CCI would reduce the number of required patients in a clinical trial. RESULTS: 682 patients (172 RC, 297 RP, 213 PN) were analyzed. Overall, 9.4-46.6% of patients had > 1 complication cumulatively assessed with the CCI resulting in an upgrading in the Clavien classification for 2.4-32.4% of patients. Therefore, scores between the systems differed for RC: CCI (mean ± standard deviation) 26.3 ± 20.8 vs. Clavien 20.4 ± 16.7, p < 0.001; PN: CCI 8.4 ± 14.7 vs. Clavien 7.0 ± 11.8, p < 0.001 and RP: CCI 5.8 ± 11.7 vs. Clavien 5.3 ± 10.6, p = 0.102. The CCI was more accurate in predicting LOS after RC than Clavien (p < 0.001). Sample size calculations based in the CCI (for future hypothetical trials) resulted in a reduction of required patients for all procedures (- 25% RC, - 74% PN, - 80% RP). CONCLUSION: The CCI is more accurate to assess surgical complications and reduces required sample sizes that will facilitate the conduction of clinical trials.

Influence of symptomatic pseudoaneurysms on postoperative renal function after partial nephrectomy: results of a matched pair analysis.

PURPOSE: A symptomatic pseudoaneurysm (SPA) is a rare but severe complication after partial nephrectomy (PN). Selective trans-arterial embolization (TAE) is the treatment of choice with high success rates. However, the influence of this intervention on postsurgical renal function has not been studied. METHODS: Between 2005 and 2016 we performed 1047 PNs at our institution. Postsurgical SPA occurred in 40 patients (3.8%). Patients with and without SPA were matched in a 1:2 ratio concerning tumor complexity (RENAL) and pre-operative renal function (CKD stage). Any CKD upstage and a relevant CKD progression (CKD ≥ III) were defined as endpoints. Furthermore, the influence of the amount of contrast agent applied during TAE was assessed. RESULTS: All patients with SPA were treated successfully with TAE. No significant difference could be detected concerning clinical, functional and surgical aspects. Median follow-up time accounted for 12.5 (6.75-27.5) months. Kaplan-Meier analyses detected an increased rate of any CKD upstage (p = 0.066) and relevant CKD progression (p = 0.01) in patients with SPA. Multivariate analysis identified post-operative SPA to be an independent predictor for a relevant CKD progression (HR 4.15, p = 0.01). The amount of contrast agents used did not have an impact on the development of a relevant CKD progression (p = 0.72). CONCLUSION: Patients treated with TAE after PN show an additional risk for an impairment of renal function over time. Hence, those patients should explicitly be informed about possible consequences and closely monitored by nephrologists.