Application of normalized values of kidney clearance function in the diagnosis of bilateral obstructive nephropathy - a preliminary report.

Background: Dynamic renal scintigraphy provides effective diagnosis of obstructive uropathy and nephropathy. However, in case of a bilateral outflow impairment, relative differential renal function (DRF), which is a primary quantitative criterion for diagnosis of unilateral obstructive nephropathy (when its value is below 45%, according to EANM guidelines from 2011), becomes unreliable. In case of bilateral nephropathy with similar severity, this parameter may even be within the normal range (45-55%) for both kidneys.

Modification of a two blood sample method used for measurement of GFR with 99mTc-DTPA.

Background: Measurements of GFR may be performed with a slope/intercept method (S/I), using only two blood samples taken in strictly defined time points. The aim of the study was to modify this method in order to extend time intervals suitable for blood sampling. Modification was based on a variation of a Russel et al.

Usefulness of clearance parametric images in detection of regional renal parenchyma dysfunction.

Background: The aim of the study was to examine whether parametric clearance images (PAR) enhance diagnostic potential of a dynamic renal scintigraphy with detection of local dysfunction of kidneys, on a model of kidneys after treatment with extracorporeal shock wave lithotripsy (ESWL), MATERIAL AND METHODS: Kidneys after ESWL were accepted as a proper model for the implementation of this objective because of the previously proven damaging effect of a shock wave on renal parenchyma and known region of ESWL application. Forty patients (23 males and 17 females) at the age of 37 to 70 years (mean value 54) with untreated earlier single, one-sided nephrolithiasis, currently treated with ESWL, underwent a study. A dynamic renal 99mTc-EC scintigraphy was performed three times: before ESWL, a week and a month after this therapeutic intervention.

Preliminary assessment of interand intraobserver reproducibility, and normative values of renal mean transit time (MTT) and parenchymal transit time (PTT) for 99mTc-etylenodicysteine.

Background: The clinical significance of MTT and PTT, determined by deconvolution of renographic curves, is arguable. Their usefulness in diagnosis of obstructive uro- and nephropathy, renovascular hypertension and monitoring of transplanted kidneys is pointed out, but susceptibility of deconvolution methods to errors resulting from "statistical noise" is also stressed. So far there are no reports on normative MTT values for 99mTc-EC, although such values were already determined for ¹³¹I-OIH, 99mTc-DTPA and 99mTc-MAG3.

Diagnostic efficacy of parametric clearance images in detection of renal scars in children with recurrent urinary tract infections.

Objective: Static renal scintigraphy with Tc-99m dimercaptosuccinic acid (DMSA) is considered a scintigraphic gold standard in detection of post-inflammatory renal scars. Reports on usefulness of conventional summed (SUM) Tc-99 m mercaptoacetyltriglycine (MAG3) or Tc-99m ethylene dicysteine (EC) dynamic scintigraphic images in detection of renal scarring are ambiguous and some authors emphasize low sensitivity of this method. The work aimed at assessment of a diagnostic efficacy of parametric clearance images (PAR) generated from a dynamic renal scintigraphy in detection of renal scars.

Assessment of accuracy and precision of (99m)Tc-HEPIDA clearances determined by means of a simplified method.

Background: The aim of the present study was the assessment of the accuracy and precision of our own simplified method for the determination of (99m)Tc-HEPIDA liver clearance.

Material And Methods: It has been assumed that archived results of plasma clearance (Cl(Pl)) and hepatic (Cl(Hp)), determined by means of multisample methods, could be legitimately used as a reference standard. The accuracy and precision of the simplified method was assessed by means of a Monte Carlo method alternatively utilizing three blood sampling times (T) of 68, 75 and 83 minutes post i.

Conventional and parametric kidney scintigrams - reproducibility of semiquantitative image evaluation.

Background: Parametric kidney scintigraphy gives the possibility of regional function distribution assessment of these organs; the clinical application of the method has thus far been limited. The usefulness of the method for the assessment of postinflammatory scars and diabetic nephropathy has been demonstrated. Preliminary data also indicate that this type of imaging allows the assessment of kidney function after extracorporeal shock wave lithotripsy.

Comparison of (99m)Tc-HEPIDA and (99m)Tc-MBrIDA from the standpoint of hepatic clearance determination-- preliminary communication.

BACKGROUND. In order to evaluate the functional capacity of the liver by means of clearance determination, the derivative of iminodiacetic acid ((99m)Tc-HEPIDA) has been used in recent decades. Because of recent problems with manufacturing and delivery of (99m)Tc-HEPIDA, an investigation was undertaken with the aim of testing whether a more widely available (99m)Tc-MBrIDA could be used for clearance determination and whether hepatic clearance measured with the use of this compound provides a similarly useful test of hepatic function.

Parametric clearance kidney scintigrams; diagnostic potential in diabetes.

Background: The diagnostic usefulness of parametric clearance kidney images was studied in the early diagnosis of diabetic nephropathy, juxtaposed with conventional dynamic urinary investigation (renoscintigraphy) combined with deconvolution procedure of renal and blood time activity curves and determination of plasma clearance of (99m)Tc-ethylenedicysteine ((99m)Tc-EC).

Material And Methods: The investigation was performed on a group of 70 individuals (41 males, 29 females) in whom diabetes type 1 was diagnosed (age 10 to 30 y.; mean 19 y.

(99m)Tc-HEPIDA hepatic clearance as a diagnostic tool: usefulness of a single sample plasma and hepatic clearance of (99m)Tc-HEPIDA for assessment of hepatic parenchyma performance.

Background: A simplified method of (99m)Tc-HEPIDA clearance determination, both plasma and hepatic, depends upon measuring the radiopharmaceutical concentration in plasma of a blood sample taken once in the time range from 68-83 min after injection of compound, and measurement of activity voided (excreted) with urine about five minutes after blood sampling. The aim of the present study was to analyze the clinical usefulness of both clearances, as determined by the simplified method in view of the diagnostic usefulness of both clearances (particularly of hepatic clearance) as determined by the respective multisampling method.

Material And Methods: For the analysis, archived data of studies in 134 individuals (48 healthy individuals and 86 patients with chronic liver parenchyma damage) were used, in which plasma clearance (Cl(Pl)) and hepatic clearance (Cl(Hp)) (99m)Tc -HEPIDA were determined by the standard multisample method--the values of such determined clearances constituted clearance referential values for further comparative analyses.

Specific 99mTC-HEPIDA hepatic clearance--essential value ranges from a clinical stand-point.

Background: Determinations of plasma 99mTc-HEPIDA clearance (ClPl) have been performed in some centres for 30 years to assess liver parenchyma damage, mostly for monitoring of organ performance in the course of various diseases. The main disadvantage of such a procedure rests with the fact that elimination of the compound from the system occurs not only via the liver and gall ducts, but also via the urinary route; the contribution of the latter compound being quite variable. This circumstance may lead to false assessment of liver parenchyma performance.

Uncertainty analysis of (99m)Tc-HEPIDA liver clearance determination.

Background: The aim of the study was to obtain information on the accuracy and precision of (99m)Tc-HEPIDA hepatic (Cl(Hp)) and plasma (Cl(Pl)) clearances and selection of an appropriate estimator of the measurement uncertainty of a single determination of these quantities.

Material And Methods: In a simulation (Monte Carlo) experiment, it was assumed that the recorded results of plasma and hepatic clearances, as obtained from 185 patients, provided authentic information about (99m)Tc-HEPIDA behaviour in the body over a wide range of the clearances studied. The time course (99m)Tc-HEPIDA concentration in blood plasma has been described by means of biexponential function with parameter values derived for each patient.

Hepatic plasma clearance of 99mTc-HEPIDA as a diagnostic tool: experimentally derived equations for a simplified determination.

Determination of the plasma (Cl(Pl)) and specific hepatic clearance (Cl(Hp)) of (99m)Tc-HEPIDA is gaining acceptance as one of the best tests for the assessment of liver parenchyma functional capacity. A standard method utilises numerous blood samples, collected after injection of the radiopharmaceutical, plus collection of the urine if specific hepatic clearance is required. It is not always necessary to obtain values of the clearances by means of the laborious multi-sample procedure.

99mTc-HEPIDA hepatic clearance as a diagnostic tool: usefulness of plasma and hepatic clearance for assessment of hepatic parenchyma performance.

Plasma clearance of (99m)Tc-HEPIDA (Cl(Pl)) has been used for two decades for assessment of liver function in patients with diseases of this organ. A specific determination of (99m)Tc-HEPIDA liver clearance (Cl(Hp)) has been developed that provides more direct possibility to evaluate performance of liver parenchyma. Both tests have been studied in healthy volunteers of varying age (48 individuals) and in 83 patients with varying degree of liver damage.