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Humans exhibit significant interindividual variability in behavioral reaction time (RT) performance yet the underlying neural mechanisms for this variability remain largely unknown. It has been proposed that interindividual variability in RT performance may be due to differences in white matter (WM) physiological properties, although such a relationship has never been demonstrated in cortical projection or association pathways in healthy young adults. Using diffusion tensor MRI (DTI), we sought to test whether diffusion tensor fractional anisotropy (FA), a measure of the orientational coherence of water self-diffusion, is regionally correlated with RT on a visual self-paced choice RT (CRT) task. CRT was found to be significantly correlated with FA in projection and association pathways supporting visuospatial attention including the right optic radiation, right posterior thalamus, and right medial precuneus WM. Significant correlations were also observed in left superior temporal sulcus WM and the left parietal operculum. The lateralization of the CRT-FA correlation to right visual and parietal WM pathways is consistent with the specialization of right visual and parietal cortices for visuospatial attention. The localization of the CRT-FA correlations to predominately visual and parietal WM pathways, but not to motor pathways or the corpus callosum indicates that individual differences in visual CRT performance are associated with variations in the WM underlying the visuospatial attention network as opposed to pathways supporting motor movement or interhemispheric transmission. diffusion tensor MRI

Background: Although various studies have documented increased life-sustaining treatments among racial minorities in medical patients, whether similar disparities exist in surgical patients is unknown. Methods: A retrospective cohort study using the Nationwide Inpatient Sample (2006 to 2011) examining patients older than 39 years who died after elective colectomy was performed. Primary predictor variable was race, and main outcome was the use of life-sustaining treatment. Results: In univariate analysis, significant differences existed in use of cardiopulmonary resuscitation (CPR; black, 35.9%; Hispanic, 29.0%; other, 24.5%; white, 11.7%; P = .002) and reintubation (Hispanic, 75.0%; other, 69.0%; black, 52.3%; white, 45.2%; P = .01). In multivariate analysis, black (odds ratio [OR], 3.67; P = .01) and Hispanic (OR, 4.21; P = .03) patients were more likely to have undergone CPR, and Hispanic patients (OR, 4.24; P = .01) were more likely to have been reintubated (reference: white). Conclusions: Blacks and Hispanics had increased odds of experiencing CPR, and Hispanics were more likely to have been reintubated before death after a major elective operation. These variations may imply worse quality of death and increased associated costs. [ABSTRACT FROM AUTHOR]

Background: The indications for carotid revascularization are based almost exclusively on the results of carotid duplex ultrasonography. Noninvasive vascular laboratories show large variation in the diagnostic criteria used to classify degree of carotid artery stenosis. We hypothesize that variability of these diagnostic criteria causes significant variation in stenosis classification directly affecting the number of revascularizations and associated costs. Methods and Results: The diagnostic criteria to interpret carotid duplex ultrasounds were obtained from 10 New England institutions. All carotid duplex scans performed at our institution were reviewed from 2008 to 2012. Using the diagnostic criteria from each institution, the degree of stenosis that would have been reported was classified as 70% to 99% asymptomatic, 80% to 99% asymptomatic, and 50% to 99% symptomatic. We then calculated the theoretical number of carotid revascularization procedures that this cohort would be offered using each institution's diagnostic criteria and the costs of these procedures based on reimbursement rates. Among 10 614 patients who underwent 15 534 carotid duplex scans, 31 025 arteries were reviewed. Application of the 10 institutions' criteria to the patients from our institution yielded marked variation in the number classified as 70% to 99% asymptomatic (range, 186-2201), 80% to 99% asymptomatic (range, 78-426), and 50% to 99% symptomatic (range, 157-781). If revascularizations were based on these results, costs would range from $2.2 to $26 million, $0.9 to $5.0 million, and $1.9 to $9.2 million, respectively. Conclusions: Differences in diagnostic criteria to interpret carotid ultrasound result in significant variation in classification of carotid artery stenosis, likely leading to differences in the number and subsequent costs of revascularizations. This theoretical model highlights the need for standardization of carotid duplex criteria. [ABSTRACT FROM AUTHOR]

Abstract: Background: Although robot-assisted laparoscopic radical cystectomy (RARC) was first reported in 2003 and has gained popularity, comparisons with open radical cystectomy (ORC) are limited to reports from high-volume referral centers. Objective: To compare population-based perioperative outcomes and costs of ORC and RARC. Design, setting, and participants: A retrospective observational cohort study using the US Nationwide Inpatient Sample to characterize 2009 RARC compared with ORC use and outcomes. Outcome measurements and statistical analysis: Propensity score methods were used to compare inpatient morbidity and mortality, lengths of stay, and costs. Results and limitations: We identified 1444 ORCs and 224 RARCs. Women were less likely to undergo RARC than ORC (9.8% compared with 15.5%, p =0.048), and 95.7% of RARCs and 73.9% of ORCs were performed at teaching hospitals (p <0.001). In adjusted analyses, subjects undergoing RARC compared with ORC experienced fewer inpatient complications (49.1% and 63.8%, p =0.035) and fewer deaths (0% and 2.5%, p <0.001). RARC compared with ORC was associated with lower parenteral nutrition use (6.4% and 13.3%, p =0.046); however, there was no difference in length of stay. RARC compared with ORC was $3797 more costly (p =0.023). Limitations include retrospective design, absence of tumor characteristics, and lack of outcomes beyond hospital discharge. Conclusions: RARC is associated with lower parenteral nutrition use and fewer inpatient complications and deaths. However, lengths of stay are similar, and the robotic approach is significantly more costly. [Copyright &y& Elsevier]

Purpose: We describe the feasibility of partial arterial clamping (PAC) during robot-assisted partial nephrectomy (RAPN). Patients and Methods: We undertook a retrospective study of five patients who underwent PAC vs 17 who underwent complete hilar clamping (CHC). Estimated blood loss (EBL), transfusion rate, operative/console time, warm ischemia time (WIT), pathology, and postoperative glomerular filtration rate (GFR) were compared. Results: PAC patients were older ( P=0.002) and more likely to have had previous abdominal surgeries ( P=0.032). PAC vs CHC was associated with higher median EBL (350 mL vs 75 mL, P=0.026), although there were no differences in blood transfusions ( P=0.250). PAC was associated with shorter WIT (14 min vs 21 min, P=0.023). Positive margin rate and GFR change were similar. Conclusions: PAC offers a simple and reproducible technique that limits WIT during RAPN. PAC was not associated with more transfusions or positive margins. Further study is warranted to determine the utility of PAC with larger tumor size as well as the long-term benefits on renal function. [ABSTRACT FROM AUTHOR]

Objectives. Retroperitoneal lymph node dissection (RPLND) outcomes for testis cancer originate mostly from single-center series. We characterized population-based utilization, costs, and outcomes and assessed whether higher volume affects outcomes. Methods and Materials. Using the US Nationwide Inpatient Sample from 2001-2008, we identified 993 RPLND and used propensity score methods to assess utilization, costs, and inpatient outcomes based on hospital surgical volume. Results. 51.6% of RPLND were performed at hospitals where there were two or fewer cases per year. RPLND was more commonly performed at large urban teaching hospitals, where men were younger, more likely to be white and earning incomes exceeding the 50th percentile (all P = .05). Higher hospital volumes were associated with fewer complications and more routine home discharges (all P = .047). However, higher volume hospitals had more transfusions (P = .004) and incurred $1,435 more in median costs (P < .001). Limitations include inability to adjust for tumor characteristics and absence of outpatient outcomes. Conclusions. Sociodemographic differences exist between high versus low volume RPLND hospitals. Although higher volume hospitals had more transfusions and higher costs, perhaps due to more complex cases, they experienced fewer complications. However, most RPLND are performed at hospitals where there were two or fewer cases per year. [ABSTRACT FROM AUTHOR]