T1 vs. T2 weighted magnetic resonance imaging to assess total kidney volume in patients with autosomal dominant polycystic kidney disease (original) (raw)
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2017
Purpose: In ADPKD patients total kidney volume (TKV) measurement using MRI is performed to predict rate of disease progression. Historically T1 weighted images (T1) were used, but the methodology of T2 weighted imaging (T2) has evolved. We compared the performance of both sequences. Methods: 40 ADPKD patients underwent an abdominal MRI at baseline and follow-up. TKV was measured by manual tracing with Analyze Direct 11.0 software. Three readers established intraand interreader coefficients of variation (CV). T1 and T2 measured kidney volumes and growth rates were compared with ICC and Bland– Altman analyses. Results: Participants were 49.7 ± 7.0 years of age, 55.0% female, with estimated GFR of 50.1 ± 11.5 mL/min/ 1.73 m. CVs were low and comparable for T2 and T1 (intrareader: 0.83% [0.48–1.79] vs. 1.15% [0.34–1.77], P = 0.9, interreader: 2.18% [1.59–2.61] vs. 1.69% [1.07–3.87], P = 0.9). TKV was clinically similar, but statistically significantly different between T2 and T1: 1867 [...
Background In autosomal dominant polycystic kidney disease (ADPKD), total kidney volume (TKV) is regarded as an important biomarker of disease progression and different methods are available to assess kidney volume. The purpose of this study was to identify the most efficient kidney volume computation method to be used in clinical studies evaluating the effectiveness of treatments on ADPKD progression. Methods and findings We measured single kidney volume (SKV) on two series of MR and CT images from clinical studies on ADPKD (experimental dataset) by two independent operators (expert and beginner), twice, using all of the available methods: polyline manual tracing (reference method), free-hand manual tracing, semi-automatic tracing, Stereology, Mid-slice and Ellipsoid method. Additionally, the expert operator also measured the kidney length. We compared different methods for reproducibility, accuracy, precision, and time required. In addition, we performed a validation study to evaluate the sensitivity of these methods to detect the between-treatment group difference in TKV change over one year, using MR images from a previous clinical study. Reproducibility was higher on CT than MR for all methods, being highest for manual and semiautomatic contouring methods (planimetry). On MR, planimetry showed highest accuracy and precision, while on CT accuracy and precision of both plani-metry and Stereology methods were comparable. Mid-slice and Ellipsoid method, as well as kidney length were fast but provided only a rough estimate of kidney volume. The results of the validation study indicated that planimetry and Stereology allow using an importantly lower number of patients to detect changes in kidney volume induced by drug treatment as compared to other methods. Conclusions Planimetry should be preferred over fast and simplified methods for accurately monitoring ADPKD progression and assessing drug treatment effects. Expert operators, especially on MR images, are required for performing reliable estimation of kidney volume. The use of efficient TKV quantification methods considerably reduces the number of patients to enrol in clinical investigations, making them more feasible and significant.
# 239 Aim: To determine whether TKV can be sequentially quantified using a 3T clinical scanner in a drug intervention study using sirolimus (S).Background: Disease progression in animal models of PKD can be assessed noninvasively by purpose-built small bore MR systems, but these are costly and not widely available. Methods: Male Lewis Polycystic Kidney (LPK) rats (model of ARPKD, n = 18) and controls (n = 8) received vehicle (V) or S (0.2 mg/kg/d by daily i.p.i) from postnatal wk3 to 10. MR scanning was performed at wks 4, 6 and 10. Rats were anaesthetised with isofluorane, and imaging was done using a clinically available wrist coil on a GE Twin Speed SIGNA HDX 3T Scanner. TKV was analysed by segmentation using a 3D SLICER toolkit. Results: A total of 32 scans were undertaken in 17 animals. At wk3 in LPK rats, TKV increased (2.5 ± 1.1 cm3) compared to Lewis rats (1.5 ± 0 cm3). Kidneys maintained a reniform shape and showed a hyper-intense linear radial appearance in the cortex and ...
Canadian journal of kidney health and disease, 2017
Autosomal dominant polycystic kidney disease (ADPKD) is an inherited disorder characterized by the formation of kidney cysts and kidney enlargement, which progresses to kidney failure by the fifth to seventh decade of life in a majority of patients. Disease progression is evaluated primarily through serum creatinine and estimated glomerular filtration rate (eGFR) measurements; however, it is known that serum creatinine and eGFR values typically do not change until the fourth or fifth decade of life. Until recently, therapy only existed to target complications of ADPKD. As therapeutic agents continue to be investigated for use in ADPKD, a suitable biomarker of disease progression in place of serum creatinine is needed. This review summarizes recent research regarding the use of total kidney volume as a biomarker in ADPKD, as presented at the Canadian Society of Nephrology symposium held in April 2015. Measurement of patients' total kidney volume made using ultrasound (US) or magn...
Kidney International, 2003
Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by gradual renal enlargement and cyst growth prior to loss of renal function. Standard radiographic imaging has not provided the resolution and accuracy necessary to detect small changes in renal volume or to reliably measure renal cyst volumes. The Consortium for Radiologic Imaging Studies in Polycystic Kidney Disease (CRISP) is longitudinally observing ADPKD individuals using high-resolution magnetic resonance (MR) imaging to determine if change in renal and cyst volumes can be detected over a short period of time, and if they correlate with decline in renal function early in disease. Standardization studies were conducted in phantoms and four subjects at each participating clinical center. After, in the full-scale protocol, healthy ADPKD individuals 15 to 45 years old with creatinine clearance>70 mL/min underwent standardized MR renal imaging, renal iothalamate clearance, comprehensive clinical evaluation, a...