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Background: A number of UK transplantation centres use isotope studies to estimate the relative contribution from each kidney in living kidney donor assessment. The evidence that the estimation of pre-donation split function of the non-donated kidney influences post-donation renal recovery is limited. The aim of this study was to analyse whether, in the context of other donor factors, the split function of the non-donated kidney predicts the percentage recovery of glomerular filtration rate (GFR) at one-year post-donation. Methodology: A retrospective cohort analysis was undertaken on 291 living kidney donors in the Glasgow Renal and Transplant Unit between 1st January 2011 and 1st June 2022. Univariable and multivariable linear regression analysis was used to analyse the impact of donor factors on recovery of renal function at one year relative to baseline isotope GFR (iGFR) or to estimated GFR (eGFR by Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] formula). Sub-analyses of donor outcome (% recovery of iGFR and eGFR at one year) were undertaken using single-measures ANOVA and grouping of donors by pre-donation isotope uptake of the non-donated kidney. Results: Median recovery of pre-donation GFR at 1 year was 70.0% (IQR 64.8-75.5). On linear regression analysis there was no significant association found between split function of the non-donated kidney and the percentage recovery of iGFR, although a small significant association was found for eGFR. There was no significant difference between mean iGFR or eGFR recovery on sub-analysis of donor outcomes. Conclusions: This study demonstrated no clinically important predictive relationship between percentage recovery of renal function at 1 year after living kidney donation and pre-donation split function within the range accepted for donation in our centre. [ABSTRACT FROM AUTHOR]

Abstract Background A number of UK transplantation centres use isotope studies to estimate the relative contribution from each kidney in living kidney donor assessment. The evidence that the estimation of pre-donation split function of the non-donated kidney influences post-donation renal recovery is limited. The aim of this study was to analyse whether, in the context of other donor factors, the split function of the non-donated kidney predicts the percentage recovery of glomerular filtration rate (GFR) at one-year post-donation. Methodology A retrospective cohort analysis was undertaken on 291 living kidney donors in the Glasgow Renal and Transplant Unit between 1st January 2011 and 1st June 2022. Univariable and multivariable linear regression analysis was used to analyse the impact of donor factors on recovery of renal function at one year relative to baseline isotope GFR (iGFR) or to estimated GFR (eGFR by Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] formula). Sub-analyses of donor outcome (% recovery of iGFR and eGFR at one year) were undertaken using single-measures ANOVA and grouping of donors by pre-donation isotope uptake of the non-donated kidney. Results Median recovery of pre-donation GFR at 1 year was 70.0% (IQR 64.8-75.5). On linear regression analysis there was no significant association found between split function of the non-donated kidney and the percentage recovery of iGFR, although a small significant association was found for eGFR. There was no significant difference between mean iGFR or eGFR recovery on sub-analysis of donor outcomes. Conclusions This study demonstrated no clinically important predictive relationship between percentage recovery of renal function at 1 year after living kidney donation and pre-donation split function within the range accepted for donation in our centre.

Abstract Purpose Our objective was to assess a deconvolution and denoising technique based on Legendre polynomials compared to matrix deconvolution on dynamic 18F-FDG renography of healthy patients. Method The study was carried out and compared to the data of 24 healthy patients from a published study who underwent examinations with 99mTc-MAG3 planar scintigraphy and 18F-FDG PET/MRI. Due to corruption issues in some data used in the published article, post-publication measurements were provided. We have been warned that post-publication data were treated differently. The smoothing method switched from Bezier to Savitzky–Golay and the deconvolution from matrix-based (with Tikhonov Regularization) to Richardson–Lucy. A comparison of the split function and mean transit times of the published and post-publication data against our method based on Legendre polynomials was performed. Results For split function, we only observed a good agreement between the processing methods for the 99mTc-MAG3 and the post-published data. No correlation was found between the split functions obtained on the 99mTc-MAG3 and the 18F-FDG, contrary to the published study. However, all calculated split function values for 18F-FDG and 99mTc-MAG3 were within the established normal range. For the mean transit time, the correlation was moderate with published data and very good with the post-publication measurements for both 99mTc-MAG3 and 18F-FDG. Bias of the Bland–Altman analysis of the mean transit times for 99mTc-MAG3 versus 18F-FDG was 1.1 min (SD 1.7 min) for the published data, − 0.11 min (SD 1.9 min) for the post-publication results and .05 min (SD 1.9 min) for our method. Conclusions The processing methods used in the original publication and in the post-publication work were quite complex and required adaptation of the fitting parameters for each individual and each type of examination. Our method did not require any specific adjustment; the same unmodified and fully automated algorithm was successfully applied to all data.

Purpose: Evaluation of split renal function (SRF) is critical for guiding surgical treatment decisions for patients with ureteral stricture disease (USD). We aimed to determine whether computed tomography (CT)-based renal parenchymal volumes may be used to predict SRF in patients with USD. Methods: We retrospectively reviewed all patients undergoing surgical management for USD at a single institution from October 2021 to January 2024. Patients who had preoperative nuclear medicine scan (NMS) and CT scan with intravenous contrast that were obtained within six weeks of each other were included. Interval between NMS and CT could be longer if the affected renal unit was drained with ureteral stent and/or percutaneous nephrostomy. Volume measurements were obtained using the 3D Region of Interest (ROI) Tool on Visage®7 Enterprise Imaging Platform (Visage Inc., San Diego, USA) by two investigators that were blinded to NMS derived SRF. Intraclass correlation coefficient (ICC) was used to assess consistency between investigators. Predictive accuracy was assessed using Pearson correlation coefficient (r) and linear regression. Results: 40 of 160 patients met inclusion criteria. There was excellent reliability in calculating renal parenchymal volume between raters (ICC = 0.990). There was a strong linear correlation between estimated CT SRF and NMS SRF (r = 0.912, p < 0.00001). A linear regression model found RObservedSRF = -0.013 + 1.015(REstimatedSRF), with r2 = 0.832. Conclusion: CT-derived parenchymal volume analysis may be used to estimate SRF in patients with USD. This may obviate the need to obtain preoperative renal scans for SRF measurement in selected patients when assessing surgical management options. [ABSTRACT FROM AUTHOR]

Robotic grasp in complex open-world scenarios requires an effective and generalizable perception. Estimating object’s pose is needed in a variety of practical grasping scenarios. Here we present a novel approach of pose estimation of textureless and textured objects. The algorithm utilizes a single RGB-D image to exploit depth invariant, oriented point pair feature as well as local contextual sensitivity in cluttered environments. To enhance the performance of the voting process and improve learning efficiency, we employ a global pruning algorithm that reduces the risk of overfitting and simplifies the structure of decision trees after compensating for the complementary information among multiple trees by optimizing a designed global objective function. Finally, we also refine the pose obtained from the above stage. The proposed approach of estimating 6-D (degree of freedom) poses of textured and textureless objects is evaluated on publicly available data sets against the recent works under various conditions. It illustrates that our framework is superior to these recent works. Further, we perform extensive qualitative experiments of robotic grasp to illustrate the proposed approach can be applied to practical scenarios. Note to Practitioners—This article is motivated by the problem of the pose estimation of textured and textureless objects in clutter environments. It is difficult for conventional works to address the issue of estimating textured or textureless objects’ poses in such scenarios. We considered that a novel system should be able to obtain the 6-D poses of objects. Therefore, we investigate the combined use of multiple split functions with different characteristics. Learning the model based on Hough forests always cost much computational resource; therefore, we construct a novel pruned Hough forest for solving this issue. Through the comparison and robotic grasp verifications, the behavior of our system can be used in practical applications. In future, we will deploy the proposed system in robotic assembling tasks. [ABSTRACT FROM AUTHOR]

Background: Obstructive uropathy refers to any blockage of urine drainage at any level of the urinary tract. It may be chronic or acute and may occur unilateral or bilateral. The prediction of the recoverability of kidney function after treatment of unilateral obstructive uropathy is of great clinical value to the urologists and nephrologists as it may affect the decision of treatment. Objectives: To detect changes in split renal function of unilaterally obstructed kidney after a period of 6 weeks of drainage. Patients and methods: This prospective observational study included 66 adult patients divided into 2 groups; Group A included patients with split function less than 10% (36 patients) and Group B included patients with split function of 10% or more (30 patients). Results: The study showed that there were an insignificant difference between the two groups in age, sex, cause of obstruction, laterality of obstruction, method of drainage and patient's presentation. Also, there was an insignificant difference between pre- and post-drainage for group A (P-value 0.142). While there was a highly significance difference between pre- and post-drainage for group B (P-value < 0.001). Conclusion: the preoperative split function of the obstructed kidney is the independent factor affecting the recoverability of renal function. Where kidneys with split function less than 10% are irreversibly damaged and the decision of treatment can be taken with no need to do drainage followed by repeating renal scan. While stabilization or improvement of renal function is expected after relief of obstruction in kidneys with split function of 10% or greater. [ABSTRACT FROM AUTHOR]

Pelvic ureteric junction obstruction (PUJO) can pose a management challenge to urologists. The natural history of the disease, particularly in adults is poorly understood and management decisions are largely based on historical, poor quality data. Additionally, many older patients may already have a degree of renal impairment secondary to systemic disease, further compounding the situation. The purpose of this paper is to detail the pathophysiology and natural history of PUJO, discuss the implications of chronic kidney disease in this population detailing the current evidence base for poorer functioning kidneys and describe the nephrological advantages of accurate renal function testing. There exists accurate methods to assess both glomerular filtration rate (GFR) and split function which could potentially provide both the urologist and patient with more relevant data on which to base their decisions when contemplating surgical intervention. The existing, low patient number case series currently published fail to address the relevance of overall GFR on the outcomes after pyeloplasty, no studies use single unit GFR and there is no clear consensus on what constitutes surgical success. PUJO is an area of benign upper tract disease that is in need of high-quality scientific studies to identify when intervention is necessary, long-term success of both surgery and conservative management in poorer functioning kidneys and clear guidelines for urologists. [ABSTRACT FROM AUTHOR]

Object detection with intraclass variations is challenging. The existing methods have not achieved the optimal combinations of classifiers and features, especially features learned by convolutional neural networks (CNNs). To solve this problem, we propose an object-detection method based on improved random forest and local image patches represented by CNN features. First, we compute CNN-based patch descriptors for each sample by modified CNNs. Then, the random forest is built whose split functions are defined by patch selector and linear projection learned by linear support vector machine. To improve the classification accuracy, the split functions in each depth of the forest make up a local classifier, and all local classifiers are assembled in a layerwise manner by a boosting algorithm. The main contributions of our approach are summarized as follows: (1) We propose a new local patch descriptor based on CNN features. (2) We define a patch-based split function which is optimized with maximum class-label purity and minimum classification error over the samples of the node. (3) Each local classifier is assembled by minimizing the global classification error. We evaluate the method on three well-known challenging datasets: TUD pedestrians, INRIA pedestrians, and UIUC cars. The experiments demonstrate that our method achieves state-of-the-art or competitive performance. [ABSTRACT FROM AUTHOR]

Functional compensation occurs in a kidney when the function of the contralateral kidney is decreased or absent. What is, however, not documented is the level of unilateral renal impairment at which functional compensation occurs. Split function, as obtained from a radionuclide renogram, can only show the asymmetry between both kidneys. The aim of the present work was to evaluate at what level of unilateral impairment a functional compensation can be observed in the contralateral normal kidney. From a large database, 180 children over 2 years of age with unilateral pathology were retrospectively selected. All of them underwent a radionuclide study, combining a technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renogram associated with a chromium-51 ethylenediaminetetraacetic acid (Cr-51 EDTA) overall clearance, allowing a precise estimation of single-kidney glomerular filtration rate (SKGFR). Below 30–35 ml/min/1.73 m2, there was a significant inverse correlation between SKGFR on the normal and the abnormal side. Above this level, no such correlation was observed, the mean SKGFR on the normal side remaining around 58 ml/min/1.73 m2, whatever the value of SKGFR on the abnormal side. In pediatric patients, hyperfunction occurs when SKGFR of the diseased kidney is below 30–35 ml/min/1.73m2. [ABSTRACT FROM AUTHOR]

Summary: Objective:: A drop of split renal function often constitutes a criterion for pyeloplasty in hydronephrosis since it is considered as representing deterioration of the affected kidney. The aim of this work was to determine, in a selected population of patients with a drop of split function of at least 5%, if the evolution of single kidney glomerular filtration rate (SKGFR) was parallel to the one of split renal function. Methods:: From a large data basis, we found retrospectively only 29 children (10 below and 19 above two years of age at first examination) having had at least two Tc-99m mertiatide (Tc-99m MAG3) renographic explorations for various urological diseases, with a decrease of split function of at least 5% between the two examinations. Evolution of split function was compared to evolution of SKGFR obtained by means of the combination of Tc-99m MAG3 split function and overall glomerular filtration rate as given by the chromium Cr 51 ethylenediamine tetraacetic acid (EDTA) clearance. Results:: For the group above two years of age, SKGFR increased or remained stable in 63% of the cases, while in the children less than 2 years of age, a decrease of SKGFR was never observed, according to the maturation of overall GFR in this age group. Thus, the decrease of split function was not necessarily associated with a similar decrease of SKGFR. Conclusion:: In patients with unilateral or bilateral urological disorders, deterioration of split renal function does not necessary correspond to a loss of function of the affected kidney. SKGFR often modifies the interpretation of split function. [Copyright &y& Elsevier]