Echo-enhanced ultrasound voiding cystography in children: a new approach.

The development of echo-enhancing agents has significantly improved the detection of the movement of fluid within the urinary tract by ultrasonography (US). The purpose of our study was to compare ultrasound voiding cystography (USVC) for the detection of vesicoureteric reflux (VUR) in children with direct radionuclide voiding cystography (DRVC). Ninety-nine children, aged 1.1-12.3 years, with 198 potentially refluxing units, were investigated simultaneously by DRVC and USVC. The indications for cystography were urinary tract infection, follow-up of a previously detected VUR, and screening of siblings of children with VUR. During the investigation an echo-enhancing agent (Levovist) was administered intravesically through a catheter already in place for the DRVC. The movement of both agents, radiotracer and Levovist, was registered simultaneously by a computerized gamma camera and US, respectively. The results were analyzed with DRVC representing the reference diagnostic test. The overall sensitivity and specificity of USVC for the detection of VUR were 79% and 92%, respectively. USVC may represent a reliable diagnostic tool for the detection and follow-up of VUR in children.

A follow-up study of vesico-ureteric reflux and renal scars in asymptomatic siblings of children with reflux.

The objectives of this study were to follow up children with vesico-ureteric reflux (VUR) and renal scars, to evaluate kidney growth and to determine the incidence of urinary tract infection (UTI) and elevated blood pressure in 40 asymptomatic siblings of children with VUR, in whom VUR had been detected at an early age, and to gather additional data which could help to evaluate the need for screening for VUR in asymptomatic siblings. During the follow-up period of 3-7 years, two children (5%) had UTI; 66% of VUR grade 1 and 2 disappeared. The progression of scars was only detected in two of nine children with renal scars on the initial study, both of whom had high-grade VUR. Renal ultrasound was normal in all siblings and none developed hypertension. The results indicate that low-grade sterile VUR may not play a major role in renal scarring, but this may not be the case with high-grade sterile VUR. Considering the correlations among VUR, UTI and reflux nephropathy, routine screening for VUR at an early age in asymptomatic siblings of children with VUR seems to be justified to identify those at the greatest risk of subsequent renal damage.

Vesicoureteric reflux and renal scars in asymptomatic siblings of children with reflux.

The purpose of the study was to determine the incidence of vesicoureteric reflux (VUR), renal scars and hypertension in asymptomatic siblings of children with VUR. The study comprised 105 siblings of patients with VUR. Their age ranged from 4 months to 6.3 years. All had a direct radionuclide voiding cystography (DRVC) performed, and VUR was detected in 47 of 105 (45%). High grade VUR in the first year of life had an incidence of 50% compared with a 9% incidence in siblings older than 2 years, while only one of the 27 siblings with a low VUR grade was younger than 1 year. In 43 of 47 siblings with VUR, a technetium-99m dimercaptosuccinic acid (99mTc-DMSA) scan was performed and renal scars were found in 10, which presents 23% of siblings with VUR who were scanned and 10% of all siblings studied. One child had hypertension. Identifying VUR among asymptomatic siblings could possibly prevent renal damage and its consequences. Thus, the predictive value of positive family history alone in identifying VUR was 45% while 23% of siblings had renal scars. This incidence justifies the routine investigation of asymptomatic siblings, by using DRVC at an early stage.

Cyclic direct radionuclide voiding cystography: increasing reliability in detecting vesicoureteral reflux in children.

The purpose of this study was to establish the sensitivity of cyclic direct radionuclide cystography (RVC) in detecting vesicoureteral reflux (VUR) in infants and small children, and to compare it to the conventional (one cycle only) RVC. 428 patients (856 renal units) were admitted to the study from January 1991 through March 1992 and all had a cyclic RVC. The age of the patients ranged from 4 months to 7 years. The overall agreement of both cycles in detecting VUR in this study was 45%, the lowest being in detecting VUR I (36%), and the highest in detecting VUR III (86%). If we had used a conventional RVC (the first cycle only), 17 (29%) VUR I, 50 (36%) VUR II and 3 (9%) VUR III, which were detected in the second cycle only, would have been missed. We conclude that cyclic RVC detected 43% more VURs than the conventional (first cycle only) RVC, and would therefore recommend its use as a standard procedure instead of the conventional RVC.

Detection of electrocardiographically imperceptible ventricular pre-excitation by phase imaging.

The sequence of ventricular contraction was studied by radionuclide phase imaging in 25 patients with Wolff-Parkinson-White syndrome. The studies were performed when no signs of precontraction were present in the electrocardiogram; in these cases pre-excitation was either intermittent or suppressable by injection of ajmaline. In 11 of the 16 patients with free wall accessory pathways, precontraction could be detected in spite of electrocardiographically absent pre-excitation. Discrete precontraction was seen also in 2 of the 9 patients with paraseptal accessory pathways. We conclude that antegrade conduction through the accessory pathway does not need to be completely blocked if signs of pre-excitation are absent on the electrocardiogram, and that phase imaging is, at least in some patients (especially those with free wall accessory pathways), a more sensitive technique for detection of pre-excitation (precontraction) than the electrocardiogram.

Association of an accessory atrioventricular pathway and ipsilateral bundle branch block.

We performed electrophysiological study and radionuclide phase imaging in a patient with intermittent Wolff-Parkinson-White syndrome type A and left bundle branch block. The presence of a left-sided accessory pathway was proven by eccentric retrograde atrial activation. Phase-imaging revealed delayed left ventricular phase angles when left bundle branch block was present in the electrocardiogram. There was an advance of early phase angles at the ventricular insertion of the accessory pathway as well as delayed phase angles in the rest of the left ventricle when the pre-excitation pattern was seen electrocardiographically.

Multiple accessory pathways: a combined electrophysiological and radionuclide study.

Electrophysiological study in a patient with Wolff-Parkinson-White syndrome revealed multiple accessory pathways: Kent bundle and Mahaim nodoventricular and fasciculoventricular fibers. Radionuclide phase imaging disclosed two distinct ventricular activation sequences during sinus rhythm or slow atrial pacing and during fast atrial pacing. The third activation pattern could be recorded after injection of ajmaline, which abolished signs of preexcitation in the electrocardiogram. Phase image in combination with pacing and pharmacological interventions can, at least in some cases, detect complex preexcitation syndromes noninvasively.

Wolff-Parkinson-White syndrome type B and left bundle-branch block: electrophysiologic and radionuclide study.

Coinciding left bundle-branch block and Wolff-Parkinson-White syndrome type B, a very rare electrocardiographic occurrence, was found in a patient with dilated cardiomyopathy. Electrophysiologic study revealed eccentric retrograde atrial activation during ventricular pacing, suggesting right-sided accessory pathway. At programmed atrial pacing, effective refractory period of the accessory pathway was 310 ms; at shorter pacing coupling intervals, normal atrioventricular conduction with left bundle-branch block was seen. Left bundle-branch block was seen also with His bundle pacing. Radionuclide phase imaging demonstrated right ventricular phase advance and left ventricular phase delay; both right and left ventricular phase images revealed broad phase distribution histograms. Combined electrophysiologic and radionuclide investigations are useful to disclose complex conduction abnormalities and their mechanical correlates.

[Early prediction of hypothyroidism after subtotal thyroidectomy (author's transl)]. / Früherkennung von Hypothyreose nach Strumaresektion.

30 patients were classified euthyroid (group A, n = 13) and hypothyroid (group B, n = 17) 4 years after subtotal thyroidectomy. A retrospective analysis of the hormonal status was then performed. In both groups (A and B) a significant decrease of serum T3 was found 3 days after surgery. 3 months later T3 levels had returned to normal. Serum T4 showed no significant change, neither at day 3 nor 3 months after the operation. Serum thyrotropin (TSH) also showed no significant change 3 days after surgery in both groups. However, 3 months later serum TSH levels were found to be significantly increased in group B (greater than 4.8 microU/ml, Mean = 13.0 +/- 6.7 microU/ml, p less than 0.001) while in group A TSH remained normal (normal range: 0--3.4 microU/ml). Assuming a serum TSH of 5.0 microU/ml as critical level at 3 months after subtotal thyroidectomy 25% of eventually hypothyroid patients will be missed and 1% will be classified hypothyroid. It is therefore suggested that all patients with serum TSH of more than 4.8 microU/ml 3 months after surgery should be considered chronically hypothyroid. The patients with a serum TSH between 3.4--4.8 microU/ml should be kept on prophylactic thyroid hormone therapy until further 3 months later the final diagnosis is established.