Isotope Renography with Special Reference to Reproducibility and Significance of Patient Position

Abstract

The reproducibility of the three parameters used in isotope renography (T/2 = time from the maximum until half the radioactivity over the kidney had been attained; t = time from injection until the maximum value was attained; and the maximum value) was studied in 41 patients by repeat tests in the same position. The influence of patient position to the same three parameters was also studied in 61 patients investigated in sitting and prone position. The values could be reproduced in 70–98% of the patients in the same position with a fairly wide definition of the concept reproducibility. Patient position was of no significance to the reproducibility. When changing from the sitting to the prone position, the maximum value decreased, while T/2 and t did not show any systematic alteration. A disparity between the function of the two kidneys was demonstrated with the same frequency in the sitting and prone position. This disparity between the two sides was more easily reproducible when X-ray examinations revealed unilateral renal disease. It is concluded that the reproducibility in isotope renography is not fully satisfactory. In the event of a disparity between the two sides the test should be repeated, and if there is a clinical or radiological suspicion of unilateral renal disease, one normal isotope renography should not be relied on, but the test repeated.

Postural Changes in Essential Hypertension under Treatment and their Effect on the Renogram

“…Other factors known to produce minor changes in the renogram (7,8,9,10,11) such as the position, hydration, other drugs and emotional state of the patients, should not interfere significantly with the results of this study, as is shown by the findings in the control group. Therefore, as long as knowledge of possible side effects of the antihypertensive treatment is inadequate, caution should be exercised in treating hypertensive patients with no clinical signs of renal abnormalities, even though a patient may have a slight impairment of the laboratory tests of renal function.…”

The ¹³¹I-Hippurate Renogram as a Quantitative Test of Function in Renal Parenchymal Disease

“…Results of renogram analysis were correlated with those obtained for the following renal function tests: blood urea nitrogen (BUN); serum fig. 1) 1 A = counts per minute (cpm) at beginning of second segment [19,26,35] 2 T a = time from injection to beginning of second segment in min [19] 3 B = peak cpm [19,26,35] 4 T b = time from injection to peak cpm in min [2,31,33] 5 B -A = increase in cpm from beginning of second segment to peak [19,38] 6 3 min -A = cpm at 3 min postinjection less cpm at beginning of second segment [28] 7 Transit time (min) = T b ~ T a [6,19] 8 Angle = degrees between AB and horizontal [19,20,32] 9 3 min -A -------------= increase in cpm from beginning of second segment to 3 min postinjec tion as fraction of cpm at beginning of second segment 10 T'/i = time in min from peak until count rate has fallen to 50% of peak cpm [2,7,16,19,20,23] 11 B -C = decrease in cpm from peak (B) to cpm 15 min after peak (C) [20] 12 Percent fall 15 min after peak = decrease in cpm from peak to 15 …”

Η Επιδρασις Της Πτωσεως Της Αρτηριακης Πιεσεως Επι Της Μορφολογιας Του Νεφρογραμματος.

“…Ή μεταβολή τής θέσεως συζητείται ύφ' ώρισμένων ερευνητών, ότι δυνατόν να μεταβάλη τήν μορφολογίαν του νεφρογράμματος, δεν υπάρχει όμως ομοφωνία επί του θέματος. Ούτω οι Friis καί Krogsgard 28 εμελέτησαν τήν έπίδρασιν τής θέσεως από καθιστικής είς πρηνή επί 61 ασθενών μέ φυσιολογικήν αρτηριακή ν πίεσιν καί εύρον, οτι ή μεγίστη τιμή τής ραδιενέρ γειας τοΰ νεφρογράμματος μειοΰται είς τήν πρηνή θέσιν, ενώ ô χρόνος ô απαιτούμενος προς καταγραφήν ταύτης καί το τρίτον σκέλος (γ) του νεφρο γράμματος δεν επηρεάζονται. Δέν δύνανται όμως ούτοι εκ των ευρημάτων των να προτιμήσουν τήν μίαν ή τήν άλλην θέσιν του ασθενούς.…”

“…Συμφώνως προς τάς παρατηρήσεις τών Friis καί Krogsgard 28 καί Nor dyke καί Tonchen 74 δέν έπρεπε να αναμένεται βελτίωσις άλλα μικρά έπι-…”