Radioisotope Renography as a Renal Function Test in the Newborn

Abstract

TechniqueLugol's iodine solution (0 2 ml) (17 3 mg total iodine and 6-6 mg free iodine) is given orally on the night before and on the evening after the test in order to block the possible uptake of any free radioactive iodine by the thyroid. Renography is carried out 1 hours after a feed to obtain a standard level of hydration. The patient is bandaged to a crucifix splint in the prone position, a detector probe is placed over the site of each kidney, and a third is positioned over the left scapular region. The probes are connected to ratemeters and recorders. The meter range employed has been 30 and the paper speed 1 25 cm/minute. Hippuran 125I 0-3 ,uCi/kg is injected rapidly into a scalp vein. For renography in children over 2 years of age we use a dose of 0 25 ,uCi/kg and a meter range of 100. The modification in technique for newbom infants is necessary to obtain sufficient amplitude in the tracing. If necessary, the positions of the kidney probes are readjusted within a few seconds of the start of the test in order to obtain maximum deflection. The renogram tracings last from 10 to 30 minutes. At the conclusion bladder radioactivity is recorded with the baby in the supine position. All recordings reproduced by recorders are from right to left-a convention in the renographic field.The following parameters were measured from renogram curves.(1) The time interval from the injection to the peak of the tracing (Tm). (2) The time interval from the injection to the point where the curve decays to 500, of the maximum (TI). (3) The amplitude of tracing is expressed by radioactive counts per second.The parameters were compared with those obtained

Experience of renal artery embolization in patients with blunt kidney trauma

“…The normal range of (T MAX ) was considered from 2.5 to 5.5 min, and the normal range of (T 1/2 ) – from 8.2 to 9.9 min [ 11 ].The renograms were considered normal if they were within these limits and abnormal if outside.…”

Experience of renal artery embolization in patients with blunt kidney trauma

“…The time interval from injection to the peak of the tracing (T MAX ); 2. The time interval from injection to the point where the curve decays to 50% of the maximum (T 1/2 ); The normal range of (T MAX ) was considered from 2.5 to 5.5 min, and the normal range of (T 1/2 ) -from 8.2 to 9.9 min [11].The renograms were considered normal if they were within these limits and abnormal if outside. Differences in the distribution of continuous variables were described in terms of the mean ± standard deviation (M ±SD) and assessed for statistical significance using Student's t test.…”

Assessment of individual renal function in children using 99mTc-DTPA.

“…However, they provide only qualitative information on differential renal function. Bilateral ureteric cannulation for the measurement of individual kidney clearances carries the risk of introducing infection and requires general anaesthesia, and is therefore not suitable for routine use. Attempts have been made for some time to assess individual renal function by noninvasive radioisotope Prince (Johnston and lIving, 1967;Kathel, 1971), and more recently methods using technetiumlabelled stannous diethylenetriaminepentaacetic acid (9imTc-DTPA) have been described (Pieretti et al, 1974;Nielsen et al, 1977). The use of deconvolution analysis to quantify the renogram and the potential advantages of this method in radioisotopic assessment of renal function have been described by Kenny et al (1975) and Diffey et al (1976).…”