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H J Testa

Publications and source records attributed to H J Testa.

At least 73 records · Page 4Linked to original sources

Regional renography in segmental renal disease.

Twenty-nine patients with symptomatic segmental renal disorders were studied by regional renography. Twenty-three patients had duplex kidneys and 6 had other segmental disease. Abnormal gamma camera findings included ureteroureteric reflux, vesicoureteric reflux, impaired function, obstruction and non-obstructive dilatation. Comparison between renography and radiology in duplex kidneys showed agreement in 10 cases. In 7 kidneys the gamma camera provided additional information and in 6 cases the X-rays alone were abnormal. It is concluded that regional renography should be performed wherever possible to complement conventional radiology in the functional and urodynamic evaluation of segmental renal disease.

Humans↗

The dilated non-obstructed renal pelvis.

This paper discusses 28 patients with renal pelvic dilatation in whom obstruction was excluded by excretion urography and diuresis renography. The clinical presentation and progress of the patients over a follow-up period of 1 to 5 years are presented. One patient required pyeloplasty, one developed 2 asymptomatic pelvic calculi and one showed some deterioration in function on the affected side. The remaining 25 patients remain well and their follow-up renograms show satisfactory renal function and excretion. Before the advent of objective means of assessing renal function and urodynamics, these patients would probably have been subjected to pyeloplasty. The present study confirms that the correct management of the dilated non-obstructed renal pelvis is conservative.

Adolescent↗

Radionuclide studies of the lower urinary tract.

The results of prospective experimental and clinical studies into the use of radionuclides in the evaluation of urinary flow rates and residual urine volume estimations are presented. The results indicate that the radionuclide estimation of flow rates is accurate, but complex and time-consuming compared with other available methods. The calculation of residual urine is simple and accurate where residual volumes are not extremely large. The opportunity for such lower tract studies after renography should not be missed where clinically appropriate, and the combined upper and lower tract studies provide a useful quantitative urological profile.

Humans↗

The plasma protein binding of HIDA.

By using Sephadex gel column chromatography to separate substances into their various components according to molecular weight, we have investigated the effect of incubating several "brands" of HIDA in plasma, in vitro. The results show that such incubation has no effect on either dimethyl HIDA, or diethyl HIDA, but that in the case of para-butyl HIDA, incubation in plasma increases the Rf value to that of HSA (human serum albumin). This indicates that para-butyl HIDA becomes bound to plasma proteins, in contrast to both dimethyl HIDA and diethyl HIDA.

Blood Proteins↗

The preparation and composition of HIDA.

The compositions of four "brands" of Tc-HIDA-dimethyl HIDA (Sorin Biomedica), diethyl HIDA (Solco), diethyl HIDA (The Radiochemical Centre), and para-butyl HIDA (Sorin Biomedica)--were investigated at varying times after their preparation from "instant kits", by using Sephadex gel column chromatography. Up to three peaks of activity were seen in each chromatogram, representing free reduced technetium, the monocomplex, and the biscomplex of Tc-HIDA respectively. In all cases the free reduced technetium component diminished to reach a plateau at less than 4% of total activity, by 1 h. In both "brands" of diethyl HIDA there was a transformation from the monocomplex to the biscomplex which took about one hour. The rate of this transformation was increased by raising the temperature of incubation, or by agitation during incubation. In the para-butyl HIDA this transformation was again noted, but was incomplete. In the dimethyl HIDA the monocomplex form was not seen. There was no noticeable disintegration of any Tc-HIDA complex up to 6 h. It is suggested that HIDA should be incubated for 1 h after preparation, before use, to achieve a stable composition.

England↗

Regional left ventricular wall motion from first-pass radionuclide angiocardiography using an Anger camera. Experimental and clinical study.

Experimental studies with a balloon phantom, and clinical studies were performed to evaluate first-pass radionuclide angiocardiography using a gamma camera in the assessment of regional wall motion. The phantom studies showed that choice of isocount contour was not critical in edge detection. Adequate count densities could be achieved, but only at the expense of temporal resolution. The clinical studies disclosed a good correlation with radiography in normal subjects and those with diffuse ventricular disease but a poor correlation in subjects with localised abnormalities of wall motion.

Cineangiography↗

HIDA scanning in gall-bladder disease.

HIDA labelled with 99Tcm is a new hepatobiliary imaging radiopharmaceutical which is selectively taken up by the liver and excreted into the biliary tree; it has been shown to demonstrate the gall bladder in normal subjects. Using a gamma-camera computer system, dynamic liver scans were performed during the first hour on 97 patients who, on the basis of standard investigations and on the findings at surgery, were divided into six groups as follows. 1. Normal. 2. Hepatocellular disease. 3. Biliary obstruction. 4. Chronic gall-bladder disease. 5. Acute gall-bladder disease. 6. Acute abdomen (not due to gall-bladder disease). Pictures were taken and activity-time curves of "regions of interest" were generated from the computer data. From these the presence or absence of a gall-bladder image was easily determined. The gall bladder was visualized in all normals but in none of the patients with acute gall-bladder disease. In the group with an acute abdomen suggestive of acute gall-bladder disease, but subsequently shown to be otherwise, the gall bladder was visualized in all cases. The gall bladder was not visualized in 42% of hepatocellular disease patients, nor in any of those with biliary obstruction, due to poor uptake or poor secretion of the HIDA. In cases of chronic gall-bladder disease, visualization of the gall bladder corresponded with gall-bladder opacification on the oral cholecystogram; in these cases the HIDA scan offers no advantage over the oral cholecystogram. These results suggest that in cases of "acute abdomen" an absent gall bladder image with a normal hepatogram will strongly support the diagnosis of acute gall-bladder disease, and that visualization of the gall bladder excludes such a diagnosis, making the HIDA scan a useful first-line investigation in these patients.

Abdomen, Acute↗

Study of right ventricular function in ischaemic heart disease using radionuclide angiocardiography.

A technique for the estimation of LVEF from first passage radionuclide angiocardiography was adapted to provide estimates of RVEF. In 17 subjects with no history of cardiovascular disease mean LVEF was 0.71 +/- 0.08 and mean RVEF 0.65 +/- 0.08. Mean values for 15 subjects with coronary artery disease but no previous history of myocardial infarction were 0.66 +/- 0.10 for LVEF and 0.65 +/- 0.08 for RVEF. Depressed ejection fractions were found after acute myocardial infarction. LVEF was lower after anterior (0.43 +/- 0.06) than inferior (0.51 +/- 0.10) infarction. RVEF was normal in the majority of subjects with anterior infarction (0.58 +/- 0.10) but was depressed after inferior infarction (0.50 +/- 0.05). Similar, although less marked, results were found in a group of subjects with old myocardial infarction.

Adult↗

Idiopathic hydronephrosis--the diuresis renogram: a new non-invasive method of assessing equivocal pelvioureteral junction obstruction.

A new method to evaluate patients with equivocal obstruction of the pelvioureteral junction is described. It involves the performance of a standard 131iodine-hippuran renogram followed by a second renogram 3 minutes after an intravenous injection of the diuretic, frusemide. When the 2 results are inspected together it is found that the patients can be separated into 4 groups: 1) normal, 2) obstructed, 3) atonic and 4) partially obstructed. The results in 23 children and 27 adults with suspected obstruction of the pelvioureteral junction are presented. Obstruction was confirmed in 18 patients and excluded in 32. The correlation between the renogram results and clinical, radiological and operative findings is discussed. The technique is simple, accurate and non-invasive, and it is recommended after excretory urography before proceeding to more invasive tests.

Adult↗

Diuresis renography and the results of pyeloplasty for idiopathic hydronephrosis.

Eighty-six kidneys in 82 patients have been assessed by diuresis renography after pyeloplasty. A non-obstructed diuresis renogram was found in 64% of kidneys. Ninety per cent of patients were clinically improved by surgery and 51% of cases studied had improved urographic features. Thirty kidneys (29 patients) were assessed both before and after pyeloplasty. An improvement in the diuresis renogram was found in 89% of cases postoperatively. Standard renography demonstrated improved drainage in only 33% of kidneys. These findings are discussed in relation to the value of diuresis renography after pyeloplasty.

Adolescent↗

Diuresis renography and morphology in upper urinary tract obstruction.

The results of a combined study of 25 patients with idiopathic hydronephrosis are presented. Diuresis renography was performed pre-operatively and surgically removed specimens of the renal pelvis and ureter were examined by light and electron microscopy. There was good correlation between the results of these 2 methods of assessment which have defined 2 broad categories of patients with renal pelvic dilatation. These findings are discussed with particular reference to the clinical value of diuresis renography.

Adolescent↗

A clinical evaluation of isotope scanning, ultrasonography and computed tomography in pancreatic disease.

In a prospective study of 46 patients with suspected pancreatic disease the provisional diagnoses arrived at independently by isotope scanning (IS), ultrasonography (USS) and computed tomography (CT) have been compared. In the control group, IS and CT were associated with a higher false positive rate than USS; The isotope scan was abnormal in most patients with proven chronic pancreatitis and cancer. The results from USS and CT were similar when structural changes were present. USS was superior in diagnosing pancreatic carcinoma and was a convenient means to follow the progression of acute pancreatitis to final resolution or the development of a pseudocyst. CT proved especially useful in accurately delineating cysts, pseudocysts and calculi prior to planning surgery and in assessing disease in contiguous viscera.

Evaluation Studies as Topic↗

Diuresis renography in equivocal urinary tract obstruction.

A trial of the value of diuresis renography in equivocal upper urinary tract obstruction is presented. Fifty-two patients were examined by standard renography and renography under a diuretic provocation. The results indicate that the technique is of considerable value in making the vital distinction between dilatation on the excretion urogram due to atonicity and that caused by a genuine obstruction. A quantitative index of the response to diuresis reflecting the degree of impedance to flow is described--the Diuresis Excretion Index. Diuresis renography is recommended in the evaluation of the patient with equivocal urinary tract obstruction.

Diuresis↗

Use of 129caesium, 99Tcm stannous pyrophosphate, and a combination of the two in the assessment of myocardial infarction.

Acutely damaged myocardium was shown in 103 patients with suspected acute myocardial infarction using 99Tcm pyp. A significant incidence of false positive and false negative results occurred, 'true' results being defined by standard clinical, electrocardiographic, and enzyme criteria. Localisation of infarction compared reasonably well with standard electrocardiographic criteria but more frequently suggested true posterior involvement. Serial estimates of infarct size may be of value in the recognition of infarct extension during the acute phase. Viable perfused myocardium was shown in 63 patients with a variety of cardiac disorders using 129Cs. The technique gives a reliable indication of anterior infarction but tends to underestimate inferior infarction. There was good correlation with the electrocardiogram with regard to localisation and extent of infarction. Nineteen patients received both isotopes and were included in each of the above groups. The combination permits further assessment of equivocal results Furthermore as 129Cs demonstrates both previous and recent infarction and 99Tcm pyp accumulates only in acutely damaged myocardium it was possible to estimate the extent of previous and recent myocardial damage.

Adult↗