title: Determination of kidney function with 99mTc-DTPA renography using a dual-head camera.
abstract: OBJECTIVE
  Single-head gamma camera renography has been used for decades to estimate kidney function. An estimate of the glomerular filtration rate (GFR) can be obtained using Tc-diethylenetriaminepentaacetic acid (Tc-DTPA). However, because of differing attenuation, an error is introduced when the kidney depth or kidney size is unequal. This error can be reduced using geometric mean data obtained from dual-head renography. The aim of this study was to compare single-head versus dual-head assessment of single kidney function.
  
  
  METHODS
  Thirty-four patients were examined with (a) single-head renography, acquiring counts from the left ventricle and kidneys from a posterior projection, and simultaneously with (b) dual-head renography, acquiring counts from the left ventricle from an anterior projection and kidneys from both anterior and posterior projections using geometric mean values. Single kidney GFR from both models was estimated (GFRcam1 and GFRcam2, respectively) and compared with GFR determined with plasma samples of Tc-DTPA (GFRps).
  
  
  RESULTS
  The prediction intervals of GFRcam1 and GFRcam2 compared with GFRps did not differ significantly (SD of GFRcam1-GFRps=17.6 ml/min and SD of GFR2-GFRps=15.5 ml/min; P=0.48). The corresponding coefficients of variation were 16.5 and 14.7%, respectively.
  
  
  CONCLUSIONS
  There is no difference in variance between GFR estimated from single-head renography and that estimated using dual-head renography. Hence, dual-head camera renography might be useful in daily practice with the potential to provide a better estimate of absolute function in each kidney and the relative kidney function in patients with differing kidney depths and/or malformed kidneys.
authors: Department of Nuclear Medicine, Herning Regional Hospital, Herning. cljuma01@heh.regionh.dk
authors: Claus J
authors: CJ
authors: Madsen
authors: Michael L
authors: ML
authors: Møller
authors: Bo
authors: B
authors: Zerahn
authors: Claire
authors: C
authors: Fynbo
authors: Jens J
authors: JJ
authors: Jensen
mesh_terms: D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011866:Radioisotope Renography / Q000295:instrumentation*; D016284:Technetium Tc 99m Pentetate
chemical_list: D016284:Technetium Tc 99m Pentetate