Variability of diuresis renography interpretation due to method of post-diuretic renal pelvic clearance half-time determination.

PURPOSE: We assessed variability in the interpretation of diuresis renography that may result from using different methods of clearance half-time determination. MATERIALS AND METHODS: We reviewed 152 diuresis renography studies performed at diagnosis or during followup of 53 children enrolled in a prospective study assessing the natural history of unilateral neonatal hydronephrosis. Studies were classified as nonobstructive, indeterminate or obstructive using 4 methods of half-time determination. Intermethod correlation and agreement were evaluated. We compared the proportion of nonobstructive, indeterminate and obstructive classifications by each method, and the interpretation of individual studies based on each method. RESULTS: Among methods we noted a high degree of correlation and fair to excellent agreement (Spearman rho = 0.86 to 0.92 and kappa = 0.57 to 0.86, respectively). However, in 27.8% of intermethod comparisons the proportion of studies classified as nonobstructive, indeterminate and obstructive differed significantly (p <0.05). The classification of pelvicaliceal drainage varied by method for all but the most severely dilated systems. In individual studies classification by 1 method was discordant with classification by another in 19% of comparisons. Of the discordant interpretations 97.7% involved nonobstructive versus indeterminate or indeterminate versus obstructive classifications. CONCLUSIONS: Variability in classifying drainage patterns based on half-time requires that practitioners be circumspect when applying this parameter for managing asymptomatic hydronephrosis. It also necessitates the description of quantitative methodology in published series of this important clinical problem.

Extension of academic pediatric radiology to the community setting: experience in two sites.

BACKGROUND: Children are better served by radiologists and technical personnel trained in the care of pediatric patients. However, a variety of obstacles may limit the access of children to dedicated pediatric imaging facilities. OBJECTIVE: We designed and implemented two models for providing community-based imaging by academic pediatric radiologists. MATERIALS: and methods. The first site was an outpatient clinic staffed by physicians from the university-affiliated children's hospital. Imaging services included radiography, fluoroscopy, and ultrasound. The second site was a full-service community hospital radiology department staffed by a group practice, with pediatric imaging covered by the children's hospital radiologists. Facility, equipment, and protocol modifications were required to maintain quality standards. Success of these models was determined by volume statistics, referring physician/patient satisfaction surveys, and quality-assurance (QA) programs. RESULTS: The outpatient satellite had a 48 % increase in total examinations from the first year to the second year and 87 % the third year. Pediatric examinations in the community hospital increased over 1000 % the first 7 months. Referring physicians reported increased diagnostic information and patient satisfaction compared to previous service. QA efforts revealed improved image quality when pediatric radiologists were present, but some continuing difficulties off-hours. CONCLUSION: We successfully implemented pediatric imaging programs in previously underserved communities. This resulted in increased pediatric radiologist supervision and interpretation of examinations performed on children and improved referring physician and patient satisfaction.

Small intestinal obstruction by remnants of the omphalomesenteric duct: findings on contrast enema.

OBJECTIVE: We reviewed the contrast enema examinations and medical records of six patients with small intestinal obstruction due to omphalomesenteric duct remnant to evaluate for characteristic imaging findings. RESULTS: In five out of the six patients the point of obstruction was demonstrated on the enema; in three patients, the characteristic "beak" of a volvulus was seen, either in the terminal ileum or cecum. In three patients, there was medial deviation of the cecum. CONCLUSION: The characteristic radiographic features of volvulus at the cecum or terminal ileum and medial deviation of the cecum should suggest persistence of an omphalomesenteric duct remnant as the etiology of obstruction in a child less than 2 years of age. The appearance of omphalomesenteric duct remnant obstruction on enema examination, though not specific, is characteristic and should be familiar to pediatric radiologists.

Vesicoureteral reflux in children: incidence and severity in siblings.

PURPOSE: We attempted to determine the incidence of vesicoureteral reflux in asymptomatic siblings of children with reflux at different ages and assess the incidence of renal damage in asymptomatic siblings with reflux. MATERIALS AND METHODS: We reviewed radionuclide cystograms of 482 consecutively referred siblings of children with vesicoureteral reflux, including 295 girls and 187 boys 2 weeks to 12.8 years old (mean age 2.8 years). Ultrasonograms and renal cortical scintigrams of children with reflux were evaluated. All siblings were considered asymptomatic by the referring physicians. RESULTS: The overall incidence of vesicoureteral reflux was 36.5%, and the incidence in girls and boys was 39.3 and 32.1%, respectively. Children 24 months old or younger had the highest incidence (45.7%) and the highest risk of bilateral reflux. From ages 25 to 72 months the incidence of reflux was 33.1% and in siblings older than 72 months it was 7%. Reflux of urine to the level of the renal pelvis was detected in 28.6% of all referred siblings. Renal damage was observed on sonography or scintigraphy in 4.7% of the siblings with reflux. CONCLUSIONS: The high incidence of vesicoureteral reflux through age 72 months indicates that it is important to screen siblings of children with reflux at an early age to prevent renal damage, which can occur in the absence of symptomatic urinary tract infection.

Hydrocele of the spermatic cord: embryology and ultrasonographic appearance.

Five cases of hydrocele of the spermatic cord are presented. All five patients had a firm inguinal mass, and ultrasonography, performed to exclude adenopathy, incarcerated hernia, and paratesticular tumor, showed an avascular cystic mass superior to and separate from the testicle. A testicular hydrocele did not coexist. This typical appearance should lead to a confident diagnosis of this benign but rare anomaly. Elective surgery may prevent the development of an acquired indirect hernia.

Fate of the reconstructed carotid artery after extracorporeal membrane oxygenation.

Reconstruction of the right common carotid artery has been shown to be feasible in neonates after extracorporeal membrane oxygenation (ECMO). However, the long-term outcome after carotid artery reconstruction (CAR) remains unknown. The purpose of this study was to evaluate the natural progression of the anastomotic site after CAR. Between February 1990 and June 1993, 201 patients received ECMO. All veno-arterial (VA) ECMO patients (n = 172) were considered candidates for reconstruction unless a significant neurological event (ie, intracranial hemorrhage, stroke) had occurred; the duration of ECMO exceeded 10 days, making carotid mobilization difficult; or the patient's prognosis was deemed poor. Reconstruction was performed by excising the arteriotomy site, followed by primary end-to-end anastomosis. Reconstruction was abandoned and the artery ligated if an intimal flap, arterial thrombosis, or excessive tension was encountered. After reconstruction all patients had early carotid ultrasonography and either head computed tomography (CT) or magnetic resonance imaging (MRI). Subsequent ultrasound examinations were performed at approximately 6-month intervals. Diameter index (DI) (a measure of anastomotic narrowing) was calculated using ultrasound by dividing the anastomotic diameter by the diameter of the carotid artery 5 mm proximal to the anastomosis. Forty-three of 172 VA ECMO patients (25%) had successful reconstruction. Long-term follow-up data were available on 27 patients. These 27 patients had 39 ultrasound examinations, with an average follow-up time of 7.3 months (range, 4 days to 29 months). All carotid arteries were patent. Linear regression analysis showed significant improvement in the DI with time (P = .0001, r2 = .382).(ABSTRACT TRUNCATED AT 250 WORDS)

Second trimester prenatal findings in duodenal and esophageal atresia without tracheoesophageal fistula.

The combination of duodenal atresia and esophageal atresia without tracheoesophageal fistula leads to a closed loop of bowel involving the distal esophagus, stomach, and duodenum. Prenatally, this association of anomalies is visualized as a characteristic dilated C-shaped fluid collection in the fetal abdomen. We report three cases of the association of duodenal and esophageal atresia without tracheoesophageal fistula, identified sonographically in the second trimester of pregnancy.

A comparison of the perioperative neurologic effects of hypothermic circulatory arrest versus low-flow cardiopulmonary bypass in infant heart surgery.

BACKGROUND: Hypothermic circulatory arrest is a widely used support technique during heart surgery in infants, but its effects on neurologic outcome have been controversial. An alternative method, low-flow cardiopulmonary bypass, maintains continuous cerebral circulation but may increase exposure to known pump-related sources of brain injury, such as embolism or inadequate cerebral perfusion. METHODS: We compared the incidence of perioperative brain injury after deep hypothermia and support consisting predominantly of total circulatory arrest with the incidence after deep hypothermia and support consisting predominantly of low-flow cardiopulmonary bypass in a randomized, single-center trial. The criteria for eligibility included a diagnosis of transposition of the great arteries with an intact ventricular septum or a ventricular septal defect and a planned arterial-switch operation before the age of three months. RESULTS: Of 171 patients with D-transposition of the great arteries, 129 (66 of whom were assigned to circulatory arrest and 63 to low-flow bypass) had an intact ventricular septum, and 42 (21 assigned to circulatory arrest and 21 to low-flow bypass) had a ventricular septal defect. After adjustment for diagnosis, assignment to circulatory arrest as compared with low-flow bypass was associated with a higher risk of clinical seizures (odds ratio, 11.4; 95 percent confidence interval, 1.4 to 93.0), a tendency to a higher risk of ictal activity on continuous electroencephalographic (EEG) monitoring during the first 48 hours after surgery (odds ratio, 2.5; 95 percent confidence interval, 1.0 to 6.4), a longer recovery time to the first reappearance of EEG activity (only in the group with an intact ventricular septum, P < 0.001), and greater release of the brain isoenzyme of creatine kinase in the first 6 hours after surgery (P = 0.046). Analyses comparing durations of circulatory arrest produced results similar to those of analyses comparing treatments. CONCLUSIONS: In heart surgery in infants, a strategy consisting predominantly of circulatory arrest is associated with greater central nervous system perturbation in the early postoperative period than a strategy consisting predominantly of low-flow cardiopulmonary bypass. Assessment of the effect of these findings on later outcomes awaits follow-up of this cohort.

Sonography with sonicated albumin in the detection of vesicoureteral reflux.

The primary radiological procedures for diagnosing vesicoureteral reflux are fluoroscopic and radionuclide cystography. Ultrasonography, with no ionizing radiation, would be useful as a screening tool for the diagnosis of reflux due to its absence of radiation exposure. We evaluated the usefulness of ultrasonography with sonicated albumin in the diagnosis of vesicoureteral reflux. Sonicated albumin contains approximately 3 to 5 x 10(8) microspheres per ml., which are echogenic. Sonicated albumin was tested in vitro, alone, and in human and porcine urine to assess microsphere stability. Urine dilutions, specific gravity, temperature and pH were used as variables. The mode of delivery was also tested in vitro and in vivo. These studies showed that sonicated albumin microspheres were stable over a wide range of chemical variables and urine composition. Sonicated albumin produced an image of uniform echogenicity when it was pre-loaded into a Foley catheter and followed by saline infusion in vitro. Fluoroscopic cystograms, using standard radiopaque contrast media, in 5 Hanford mini-swine in which unilateral reflux had been created previously confirmed the presence of reflux unilaterally. Sonographic cystograms with various dilutions of sonicated albumin in 0.9% sodium chloride (1:100, 1:250, 1:500, 1:750 and 1:1,000) were performed. At a dilution of 1:100 sonicated albumin produced dramatic echogenicity in the bladder and refluxing ureters during sonographic imaging. The microspheres appeared to be stable for prolonged periods (more than 40 minutes), thus allowing for a careful sonographic assessment of the entire genitourinary tract. Sonicated albumin may be valuable for the sonographic detection of vesicoureteral reflux.

Ultrasonography of the female pelvis in childhood and adolescence.

The age of the patient is crucial in the consideration of differential diagnoses for pelvic disease. This is especially true in the pediatric population. Ultrasonography is the first, and often only, imaging required for female babies, children, and young adults who present with signs and symptoms referable to the pelvis. Usually, children come to attention because of pelvic mass, pelvic pain, ambiguous genitalia, or abnormal sexual development. It should be remembered that congenital anomalies may not become apparent until the onset of puberty. In all cases, good practice requires that adnexal and uterine anatomy and screening views of each kidney are documented on hard copy. Further evaluation, which consists of MR or CT scanning, depends on the results of the ultrasonograms, the clinical examination, and acuity of the problem.

Urolithiasis in a children's hospital: 1985-1990.

We performed a retrospective study of patients who had urinary tract stones and were seen at our hospital from 1985-1990. The study was intended to determine the prevalence of urolithiasis and optimal approaches to imaging. Clinical data and imaging studies of 87 patients were reviewed. The mean age was 15.7 years with a range of 3 months to 44 years. Fifty-four percent of patients were male. Most patients had a known predisposing cause for urolithiasis; patients with myelodysplasia and structural urologic problems predominated. Plain films were performed in 77 patients; 57% showed stones. Ultrasonograms were performed in 71 patients; 77% showed stones. Excretory urograms (EU) were performed in 49 patients; 84% showed either stones or their effect on the urinary tract. Computed tomographic (CT) scan was performed in 25 patients; all showed stones.

Use of ultrasonography in dysplasia of the immature hip.

Real-time ultrasonography reconstruction is an imaging technique of relatively recent origin that has dramatically affected the diagnosis and treatment of patients with hip dysplasia. Ultrasonography is replacing conventional radiography as the primary method of diagnosing hip dysplasia and evaluating its treatment during the first six to nine months of life. While conventional radiography reveals a familiar two-dimensional image of ossified structures and to a much lesser extent, soft-tissue structures, it has disadvantages that include ionizing radiation, a relative inability to evaluate unossified tissues, and an inability to gain three-dimensional information without supplemental techniques.

The unsuspected double collecting system on imaging studies and at cystoscopy.

Five children (three girls and two boys) who had a duplex collecting system with an ectopic ureter or a ureterocele that was not detected with either imaging or cystoscopy were seen during a 10-year period. Four had urinary tract infection. The fifth was noted to have hydronephrosis when CT scanning of the abdomen was done for trauma. In each case, voiding cystourethrography showed reflux into what was thought to be a single (nonduplex) collecting system, but was found during surgery to be the lower pole of a duplex system. Excretory urography in four patients, sonography in two, and CT scanning in one did not show signs of duplication on the affected side. In each case cystoscopy failed to show a duplex system on the affected side. The diagnosis of duplication of the collecting system with ectopic ureter or ureterocele was made in each case only when the bladder was opened to reimplant the ureter. Direct opacification of the previously unsuspected upper pole ureter in each case showed it to be bind-ending and terminating at the level of the kidney. Radiologists and surgeons should be aware that duplex systems may not always be visible on urography and sonography.

Unsuspected hepatic injury in the neonate--diagnosis by ultrasonography.

Three cases of severe neonatal hepatic injury were investigated with ultrasonography. The injury is often associated with antenatal factors (fetal hepatic enlargement, maternal trauma), perinatal factors (breech presentation, pre- or post-maturity, difficult delivery), or postnatal factors (resuscitation).

Juvenile pilocytic astrocytomas: CT and MR characteristics.

Thirty-seven cases of juvenile pilocytic astrocytoma were reviewed retrospectively to determine their CT and MR characteristics. All cases occurred in pediatric patients, except for one in a young adult. There was a propensity for tumors to be located around the third and fourth ventricles. On CT the tumors were all sharply demarcated and smoothly marginated and rarely had associated edema. The lesions tended to be round or oval. The tumor matrix was most often hypo- or isodense with marked enhancement. Cyst formation, either micro- or macrocystic or combined, was frequently observed, and tumor calcification occurred occasionally. On MR the tumors appeared hypo- or isointense on T1-weighted images and hyperintense on T2-weighted images. The radiologic appearances of juvenile pilocytic astrocytomas are quite characteristic. By using age of presentation, typical location, configuration, and enhancement patterns, the presurgical diagnosis of juvenile pilocytic astrocytoma can be made with a high index of confidence.

Ectopic ureterocele without ureteral and calyceal dilatation (ureterocele disproportion): findings on urography and sonography.

Eight infants and children (six girls) were seen over a 13-year period with duplex collecting systems and ectopic ureteroceles. In each, there was striking dissimilarity in size between the large ureterocele and its diminutive ureter and calyces. The upper moiety did not function and, except for the ureterocele, the indirect urographic and direct sonographic signs of duplication were absent or subtle. We call this entity ureterocele disproportion. Seven patients presented with urinary infection and one was found to have hydronephrosis of a dilated lower moiety in utero. Five had ipsilateral lower-pole reflux, which ranged in degree from 3 to 5 (on a scale of 1-5). Two had bilateral duplication; one of these had a typical contralateral ectopic ureterocele. The diagnosis of ureterocele disproportion was strongly suggested by urography and sonography and was confirmed at cystoscopy by direct puncture of the ureterocele and opacification of the upper moiety. All had surgery. The approach varied and depended on the status of the lower moiety and the contralateral kidney. One had incision of the ureterocele only. Five with lower-pole reflux had excision of the ureterocele and ipsilateral common-sheath reimplantation.