Renography, dynamic

A plethora of methods has been developed to evaluate renal function by dynamic renography and remote analysis of the excretion of renal function markers. The underlying principle is that the kidneys excrete a majority of small hydrophilic molecules and their clearance, secretion, or fixation in the kidney is quantifiable. When a renal marker in plasma is filtered through the glomeruli, the accumulation of the filtrate in the Bowman s capsule. One or more of the following events may occur in the renal tubule once a marker is filtered or is in plasma [171] ... 

Although dynamic renography has been used for decades, one must nevertheless ensure that the data are acquired adequately and processed according to well-established guidelines and that the interpretation of the results is based on published supported information wherever possible. 

Dynamic renography allows estimation of three parameters of renal function blood flow to the kidney renal clearance (Prigent et al. 1999 Rutland 1985 PiEPSz et al. 1998), i.e., the extraction of a tracer from the blood, when estimation of relative clearance occurs as in differential renal function (DRF) and the drainage function or excretion from the kidney. 

The strengths of dynamic renography lie in the ability to routinely quantify DRF and drainage serial renography is also reliable. There is a low radiation burden, especially using the agents with tubular extraction. 

Dynamic renography assesses renal blood flow, differential function and drainage. Indications are assessment of pre- and posturological surgery in children. In the presence of dilatation it assesses function and drainage. 

The dynamic renogram is only of diagnostic value if glomerular renal function is normal and both kidneys appear normal in the ultrasonographic evaluation. It is important that dynamic renography is performed with an empty bladder to exclude an obstruction at the ureterovesical junction. Therefore, in infants the use of an indwelling bladder... 

Dynamic studies providing information on renal function (camera renography)... 

Depending on the parameters to be studied and the method to be used, 37-185 MBq (1-5 mCi) are used in adults (70 kg). Studies of renal blood flow or transport through the ureters generally require a larger dose than do studies of intrarenal transport whereas renography requires smaller activities than dynamic sequential scintigraphy. 

Lee VS, Rusinek H, Noz ME, Lee P, Raghavan M, Kramer EL (2003) Dynamic three-dimensional MR renography for the measurement of single kidney function initial experience. Radiology 227 289-294... 

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