Fully Automatic Region of Interest Selection in Glomerular Filtration Rate Estimation from 99mTc-DTPA Renogram

Abstract

Glomerular filtration rate (GFR) is a common accepted standard estimation of renal function. Gamma camera-based methods for estimating renal uptake of (99m)Tc-diethylenetriaminepentaacetic acid (DTPA) without blood or urine sampling have been widely used. Of these, the method introduced by Gates has been the most common method. Currently, most of gamma cameras are equipped with a commercial program for GFR determination, a semi-quantitative analysis by manually drawing region of interest (ROI) over each kidney. Then, the GFR value can be computed from the scintigraphic determination of (99m)Tc-DTPA uptake within the kidney automatically. Delineating the kidney area is difficult when applying a fixed threshold value. Moreover, hand-drawn ROIs are tedious, time consuming, and dependent highly on operator skill. Thus, we developed a fully automatic renal ROI estimation system based on the temporal changes in intensity counts, intensity-pair distribution image contrast enhancement method, adaptive thresholding, and morphological operations that can locate the kidney area and obtain the GFR value from a (99m)Tc-DTPA renogram. To evaluate the performance of the proposed approach, 30 clinical dynamic renograms were introduced. The fully automatic approach failed in one patient with very poor renal function. Four patients had a unilateral kidney, and the others had bilateral kidneys. The automatic contours from the remaining 54 kidneys were compared with the contours of manual drawing. The 54 kidneys were included for area error and boundary error analyses. There was high correlation between two physicians' manual contours and the contours obtained by our approach. For area error analysis, the mean true positive area overlap is 91%, the mean false negative is 13.4%, and the mean false positive is 9.3%. The boundary error is 1.6 pixels. The GFR calculated using this automatic computer-aided approach is reproducible and may be applied to help nuclear medicine physicians in clinical practice.

An Approach to Classify Chronic Kidney Diseases using Scintigraphy Images

“…The process of manually marking the regions of interest (ROI) is time consuming, tedious and depends on the specialist skill. Consequently, the results are dependent on the person processing the exam, which can compromise the reproducibility of the method [10]. Thus, methods have been proposed to support the definition of ROIs.…”

“…Nevertheless, it is necessary an input provided by the operator in order to correctly segment the kidneys. In [10], their automatic segmentation approach could not segment a patient kidney with poor renal function.…”

A New Approach for Split Renal Function Evaluation of Glomerular Filtration Rate, Perfusion and Plasma Flow by Numerical Analysis of 3d MSCT-Based Models

“…It is a researcher-dependent way of split kidney function assessment. As well as that results of RS may depend on patient's weight and patient's body movements during the procedure [2,7]. However, it is commonly used in the clinical settings [4,5,8].…”

Glomerular filtration rate measured by 99mTc‐DTPA renal dynamic imaging is significantly lower than that estimated by the CKD‐EPI equation in horseshoe kidney patients

“…They are non‐invasive, simple, and relatively accurate. Furthermore, renal dynamic imaging, also named Gate's method, is another method for measuring GFR due to the following advantages: achievement of unilateral renal blood flow and kidney function; the entire procedure is performed in approximately 20 min; no blood or urine collection is needed; and its result is not affected by the diet of the patient . However, it is unclear whether the isotope renal dynamic imaging can accurately assess renal function in HSK patients with renal fusion anomalies.…”

“…Thus, GFR can be accurately measured using 99m Tc‐DTPA . The patients were hydrated with 300–500 mL water 20 min prior to the examination . The patients laid down on the bed, and then a 5 mCi (185 MBq) count of the syringe containing 99m Tc‐DTPA was performed before injection.…”