Normal Renogram Research Articles

Uses and limitations of renal scintigraphy in renal transplantation monitoring.

The value of thrice weekly technetium-99m mercaptoacetyltriglycine renography after renal transplantation was investigated in 213 consecutive transplants. A grading system was used: 0 = normal renogram; 1 = normal uptake, reduced excretion; 2 = normal uptake, flat excretion curve; 3 = rising curve; 4 = reduced rate of uptake, rising curve and reduced absolute uptake; 5 = minimal uptake. The initial renogram grade (RG) was primarily a marker of ischaemic damage, being poorer with cadaver donation, long cold ischaemia (>24 h), and high donor and recipient age. High primary RG predicted primary graft non-function, long time to graft function, low discharge Cr EDTA clearance and low 1- and 5-year graft survival. Discharge RG predicted late (>6 months) graft loss. RG was highly correlated (P<0.001) with creatinine and creatinine clearance, and changes in RG were correlated with changes in renal function. A change in RG of 0.5 was non-specific, while a change of 1 or more predicted clinical complications in 95% of cases. The negative predictive value was low (58%). RG change antedated clinical diagnosis in only 38% of cases, and in only 14% of acute rejections did an RG change of 1 or more antedate a rising creatinine. RG did not contribute to the differential diagnosis between acute rejection, acute tubulointerstitial nephropathy and cyclosporine toxicity. In conclusion, an initial renography after transplantation is valuable as it measures ischaemic damage and predicts duration of graft non-function and both short and long-term graft survival. A review of the literature suggests that the indication for serial scintigraphic monitoring for functioning grafts is less certain: the diagnostic specificity is insufficient for it to be the definitive investigation for common diagnostic problems and it does not give sufficient advance warning of impending problems.

Urography and renography in the follow-up of patients with toxemia of late pregnancy.

We have studied 129 patients with toxemia of pregnancy two months post partum by urography and renography. The same investigations were performed on 17 healthy parturients post partum. 49 patients (38.8%) had an abnormality either in urography or renography. 20 patients (15.5%) had an abnormal urogram and 42 (32.6%) an abnormal renogram. The findings correlated so that 7 patients had an abnormal urogram with a normal renogram and 13 patients had an abnormality in both investigations. 29 patients had only an abnormal renogram. In the control series 3 patients had an abnormal urogram and the same patients also had an abnormal renogram. We divided the studied patients into groups according to the clinical severity of toxemia. Urographic and renographic findings were divided evenly in the series so that abnormalities were no more common in the severe cases. Renography cannot be considered merely as a screening method when compared with urography in the follow-up of toxemic patients, but these investigations are complementary.

The value of renography in the assessment of obstruction in the upper urinary tract. An investigation of 45 cases of carcinoma of the cervix uteri treated by Wertheim hysterectomy.

Simultaneous renography and intravenous urography have been done to assess the value of renography in detecting the presence of upper urinary tract obstruction. 45 women were treated by Wertheim's operation (radical hysterectomy and pelvic lymph node dissection) and were investigated preoperatively and at 14 days, 2–6 months and 1, 2 and 3 years postoperatively. A total of 193 investigations have been done. Good agreement was found in 33 cases, i.e. 73% (21 had normal flow and 12 had varying degrees of obstruction). A false diagnosis of obstruction was made in 8 cases (i.e. 17%) after renography and in 3 cases after i.v. urography. Renography would appear to be a reliable screening method for detecting ureteric obstruction after Wertheim's operation. A normal renogram excludes obstruction. Abnormal renograms should be followed by urography, not only because the high sensitivity of renography can lead to a false diagnosis of obstruction, but also to delect the site of the lesion.

The use of radioactive hippuran in the management of cadaveric renal transplants.

Abstract The use of a combined radiohippuran clearance and renogram with blood background subtraction in 35 recipients of a cadaveric renal transplant is described. The presence of renal blood flow during the initial oliguria can be demonstrated by this technique. The renogram during the postoperative period of acute tubular necrosis usually continues to rise until 30 minutes and no peak is seen. After diuresis most patients are found to have a normal renogram and to have had a significant rise in radiohippuran clearance. Characteristic abnormalities may be seen with acute and chronic rejection or urinary obstruction and these abnormalities are reversed if treatment is successful. There are still limitations to the use of renography in the diagnosis of acute rejection or obstruction during the initial oliguria. The combined test is of value in the management of cadaveric renal transplantation.

The radioisotope renogram in carcinoma of the cervix.

One hundred and forty-three patients with carcinoma of the cervix of the uterus were studied prospectively. All had pretreatment, intravenous pyelograms and radioisotope renograms. The results of the investigations have been compared and their relationship to the prognosis in the disease is shown. A normal renogram before treatment is more often associated with freedom from pelvic disease than a normal I.V.P. An abnormal renogram before treatment is more often associated with recurrence of disease than an abnormal I.V.P.

Digital computer simulation study of the radio-Hippuran renogram

A digital computer model of the radio-Hippuran renogram has been developed to simulate the normal renogram previously described for this laboratory. The parameters used correspond to previously established physiologic values whenever such data were available, e.g. plasma volume, effective renal plasma flow, renal transit time and cardiac output. The apparent Hippuran space and body background were determined from patient studies. Intercompartmental transfer and intra-renal mixing rates were of necessity computer derived from the best fit. The model gives an estimate within ±5 per cent of the mean normal renogram and the 30-min excretion. Model results do not correspond as closely to the apparent Hippuran space. A simultaneous good fit of all three results does not appear possible with any combination of parameters which differ greatly from the values used. The model successfully simulates disease states, such as reduction in renal blood flow, mechanical obstruction and renal artery stenosis.

CRITERIA FOR SCREENING THE HYPERTENSIVE PATIENT WITH RENAL-ARTERY OCCLUSION.

An orderly search for a surgically correctable vascular lesion is necessary in the diagnostic evaluation of the hypertensive patient. A series of 210 cases were evaluated with a view toward appraising the relative merits of the intravenous pyelogram, radioisotope renogram, renal arteriogram, and differential renal-clearance studies as screening procedures. With a normal intravenous urogram and a normal renogram, one can be reasonably assured that a surgically correctable vascular lesion due to atheroma is not present. When either the pyelogram or the renogram is abnormal, the hypertensive patient should have a renal arteriogram. When an operable vascular lesion is anatomically demonstrated on the arteriogram, the work performance of the individual kidneys should be determined with split renal-clearance studies before the patient is considered as a candidate for vascular-reconstructive surgery.

A TRIAL OF THE RADIOISOTOPE RENOGRAM.

SUMMARY 1 The factors governing the shape of the normal renogram have been discussed 2 The results of seventy consecutive renograms are presented and analysed. 3 The rate of fall of the third phase of the renogram has been shown to be an inverse linear function of the creatinine clearance rate and a linear function of age. 4 In a group of twenty-seven hypertensive patients two false negative results were found in five patients with unilateral renal disease and seven false positive results were found in twenty-two patients who did not have unilateral renal disease. I wish to thank the physicians and surgeons of Charing Cross Hospital, Fulham Hospital, and the West London Hospital who sent patients for renogram investigation. I also thank Mr N. W. Ramsey for his help in setting up the apparatus, Dr J. Swales for preparing the hippuran for our early tests, and Miss J. Godden who helped to perform the renograms. Finally I would like to thank Dr D. R. McPherson for his help with the abdominal X-rays and the I.V.P.'s, and Mr B. Armitage for help with references.

Analysis of the I-131 sodium o-iodohippurate renogram.

THE ADMINISTRATION of a radioactive compound which is rapidly picked up and excreted by the kidney has been shown to produce a characteristic curve when recorded by duoscintillalor counters. Since Taplin and co-workers' original work in 1956, this phenomenon has been used as a qualitative kidney function test. Certain modifications have appeared which now include the use of the superior vehicle I¹³¹sodium o-iodohippurate (Hippuran). However, the original description of the components of the curve has been essentially unchanged. Winter has described the curve as follows: "The initial spike represents the vascular capacity of the kidney plus that of the background tissue. . . . The secondary rise in the tracing beginning during the second or third minute and lasting three to five minutes is due to tubular cell secretion of the contrast medium. . . . The third and final leg in the normal renogram is the descent in

A study on radioisotope renogram

Concerning radioisotope renogram, following investigations were made in respect of: 1) the requirements for measuring apparatus and its measuring method, 2) the results of animal experiments and 3) on the appraisal of its clinical application.1) The measuring apparatus were fixed with a collimeter and a discriminater, thereby accuracy was highly assured. As to the measuring method, the dosage was fixed at the rate of 4μc per 10kg body weight, and examinees were given diuresis to accelerate the urination. Measurements were taken mainly in sitting position. The test materials were: 131I-Diodrast, 131I-Urokon and 131I-Hippuran.2) The experiments were conducted with 131I-Diodrast on adult dog, with normal kidney, with stricture of renal arterie, with hydronephrosis, with absence kidney, etc. The normal renogram curves shows three segments which are characteristic of normal kidney, especially the renal tubular function and retention in the renal pelvis were clearly indicated. The renogram of diseased kidneys show varied curves of the split function, correspondingly to each cases.3) Clinical experiments consist of 381 cases; namely 350 Diodrast cases, 21 Urokon cases and 10 Hippuran cases. For the analysis of renogram, renal vascularity value, retention rate, maximum count, peak time and half crest count time etc. were determined as the normal renogram base factors. A close relationship were observed between the qualitative classification of renogram curves and fraction data of p. s. p test.The clinical application also proved that renogram was useful in the practice of determining various values in clinical cases, suggestes its useful application not only in urology but also in field of internal medicine.