Michael A. DiPietro

RENAL SONOGRAPHY IS NOT A RELIABLE SCREENING EXAMINATION FOR VESICOURETERAL REFLUX

A retrospective analysis of 493 infants and children was performed to determine the reliability of renal sonography for identifying vesicoureteral reflux. Sonography was done in all cases within 8 hours of a voiding cystourethrogram. Vesicoureteral reflux was documented in 272 of 986 kidneys on voiding cystourethrography and there were 201 refluxing kidneys with normal ultrasound (25 with grade I reflux, 119 with grade II, 50 with grade III, 6 with grade IV and 1 with grade V). In 71 of the refluxing kidneys the ultrasound was abnormal due to pelvicaliceal dilatation in 45, a duplication anomaly in 6 and renal fossae abnormality in 20. Of the kidneys with vesicoureteral reflux 74% were sonographically normal. Sonography was not sufficiently sensitive or specific for detecting vesicoureteral reflux, since 28% of the missed refluxing kidneys had grade III or higher reflux.

Diagnosis and management of congenital cystic disease of the lung in children

Pulmonary sequestration, congenital adenomatoid malformation (CAM), congenital lobar overinflation (CLO), and bronchogenic cysts are four congenital lesions that may present as abnormal cystic areas within the pleural cavity in early life. They share similar clinical and embryologic characteristics, are frequently difficult to diagnose, and all require surgical treatment. From December 1974 to January 1985, 22 patients were operated upon on the Pediatric Surgical Service for congenital cystic disease of the lung. There were eight females and 14 males, ranging in age from 1 day to 18 years; 12 were under 6 months of age, and 14 were under one year. There were 7 CAMs, 5 extralobar pulmonary sequestrations, 5 intralobar pulmonary sequestrations, 3 bronchogenic cysts, and 3 cystic lobes caused by CLO. One patient had bilateral pulmonary sequestrations, intralobar on one side and extralobar on the other, with both sharing a common systemic artery arising from the infradiaphragmatic aorta. All except two asymptomatic patients presented with either progressive respiratory distress or recurrent pulmonary infections, and had cystic changes noted on chest roentgenograms. The differentiation of these congenital lesions from resolvable inflammatory cysts is important. Diagnosis was aided by selective utilization of barium contrast studies, ultrasonography, computed tomography, and arteriography. Operation consisted of resection alone of the extralobar pulmonary sequestrations and bronchogenic cysts, and total lobectomy in CAM, intralobar sequestration, and CLO. One infant with CAM died 1 day postoperatively from bilateral hypoplastic lungs. The other 21 patients are alive and well with follow-up ranging from 1 month to 9 years, with a mean of 3.5 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful treatment of neonatal arterial thromboses with recombinant tissue plasminogen activator

Seven newborns were treated with recombinant tissue plasminogen activator for arterial thromboses. Complete lysis occurred in four of seven and partial in two of seven patients. Serious bleeding complications were observed in two of seven patients. This and published experience suggest that successful lysis with recombinant tissue plasminogen activator occurs in most patients and that hemorrhagic complications are unusual but are not.

Transient small-bowel intussusception in children on CT.

ObjectiveTo determine the frequency and significance of small-bowel intussusception identified in children on CT.Materials and methodsAll abdomen CT reports between July 1995 and April 2002 were reviewed to identify patients with small-bowel intussusception. Intussusceptions were identified as an intraluminal mass with a characteristic layered appearance and/or continuity with adjacent mesenteric fat. Ileocolic intussusceptions and intussusceptions related to feeding tubes were excluded. Imaging studies and medical records were reviewed.ResultsTwenty-five pediatric patients (16 boys, 9 girls; mean age 11.2 years) were identified with small-bowel intussusception on CT. No patient had a persistent intussusception requiring surgery. Fourteen had limited immediate repeat CT images as part of the same examination, ten of which demonstrated resolution of the CT abnormality. Follow-up CT [n=13 (6 within 24 h)], ultrasound (n=3), small-bowel follow-through (n=4) and surgery (n=3) showed no intussusception. In four patients with persistent symptoms, underlying pathology was identified requiring treatment (giardiasis, 2; small-bowel inflammation/strictures, 1; abscess and partial small-bowel obstruction after perforated appendicitis, 1). In 21 other patients, direct correlation of symptoms to CT abnormality was absent or questionable, no treatment was required, and there was no clinical or imaging evidence of persistence or recurrence.ConclusionMost small-bowel intussusceptions identified in children by CT are transient and of no clinical significance.

Sonographic Twinkling Artifact for Renal Calculus Detection: Correlation with CT

PURPOSE To retrospectively correlate sonographic color Doppler twinkling artifact within the kidneys with unenhanced computed tomography (CT) in the detection of nephrolithiasis. MATERIALS AND METHODS Institutional review board approval was obtained for this retrospective HIPAA-complaint investigation, and the informed consent requirement was waived. Sonographic imaging reports describing the presence of renal twinkling artifact between January 2008 and September 2009 were identified. Subjects who did not undergo unenhanced abdominal CT within 2 weeks after sonography were excluded. Ultrasound examinations were reviewed by three radiologists working together, and presence, number, location, and size of renal twinkling artifacts were documented by consensus opinion. Sonographic findings were correlated with unenhanced CT (5-mm section width, no overlap) for nephrolithiasis and other causes of twinkling artifact. The number, location, and size of renal calculi at CT were documented. RESULTS The presence of sonographic renal twinkling artifact, in general, had a 78% (95% confidence interval: 0.66, 0.90) positive predictive value for nephrolithiasis anywhere in the kidneys at CT. The true-positive rate of twinkling artifact for confirmed calculi at CT was 49% (73 of 148 twinkling foci), while the false-positive rate was 51% (75 of 148 twinkling foci). The overall sensitivity of twinkling artifact for the detection of specific individual renal calculi observed at CT was 55% (95% confidence interval: 0.47, 0.64). CONCLUSION While renal twinkling artifact is commonly associated with nephrolithiasis, this finding is relatively insensitive in routine clinical practice and has a high false-positive rate when 5-mm unenhanced CT images are used as the reference standard. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11102128/-/DC1.

Ureaplasma urealyticum and chronic lung disease in very low birth weight infants during the exogenous surfactant era.

BACKGROUND An association between recovery of Ureaplasma urealyticum from the respiratory tract of very low birth weight (VLBW) infants (< or =1500 g) and later chronic lung disease (CLD) was reported by several authors before the routine use of exogenous surfactant (SURF). We sought to assess whether this relation persists in the era of routine SURF. METHODS We prospectively studied a cohort of 105 VLBW infants who required mechanical ventilation at < 12 h of age. Tracheal aspirates for U. urealyticum culture were obtained before administration of SURF or antibiotics. Clinicians were unaware of U. urealyticum status. Chest radiographs at 28 days were reviewed by a single pediatric radiologist, blinded to U. urealyticum status. Sample size was predetermined to detect a 30% increase in CLD among those with U. urealyticum recovery from tracheal culture (U. urealyticum-positive) with alpha <0.05 and beta <0.20. RESULTS Of the study infants 22 were U. urealyticum-positive and 83 were U. urealyticum-negative. No differences were found between the groups for birth weight, gestational age, gender, inborn, antenatal or postnatal steroid use, SURF therapy, non-U. urealyticum infection, necrotizing enterocolitis, patent ductus arteriosus, intraventricular hemorrhage or cystic periventricular leukomalacia. At 28 days U. urealyticum-positive patients were significantly more likely to have CLD than U. urealyticum-negative [15 of 22 (68%) vs. 30 of 83 (36%); P < 0.02]. The U. urealyticum-positive patients also required significantly longer courses of supplemental oxygen and mechanical ventilation. No significant differences were found for CLD at 36 weeks postconception or duration of hospitalization, although type II error could not be excluded for these secondary endpoints. CONCLUSIONS Respiratory U. urealyticum at or shortly after birth remains associated with CLD at 28 days despite routine use of SURF. Controlled trials of anti-Ureaplasma therapy in U. urealyticum-positive VLBWs as soon after birth as possible may determine whether CLD, duration of respiratory support and attendant costs can be decreased.

Testicular infarction in the newborn: Ultrasound findings

Three patients with neonatal testicular torsion and infarction (two bilateral, one unilateral) are presented with a distinctive sonographic appearance. All five testes appeared inhomogeneously hypoechoic and each was surrounded by a brightly echogenic rim. Whereas surgical exploration was required in the past to establish the diagnosis of testicular infarction in the neonate, sonographic demonstration of the abnormality in the appearance of the testicular parenchyma permits nonoperative diagnosis. Because surgical salvage of the testis in the setting of neonatal extravaginal torsion is thought to be quite rare, the necessity of removing the testis is less clear when the diagnosis is established preoperatively.

National Ultrasound Curriculum for Medical Students

Abstract Ultrasound (US) is an extremely useful diagnostic imaging modality because of its real-time capability, noninvasiveness, portability, and relatively low cost. It carries none of the potential risks of ionizing radiation exposure or intravenous contrast administration. For these reasons, numerous medical specialties now rely on US not only for diagnosis and guidance for procedures, but also as an extension of the physical examination. In addition, many medical school educators recognize the usefulness of this technique as an aid to teaching anatomy, physiology, pathology, and physical diagnosis. Radiologists are especially interested in teaching medical students the appropriate use of US in clinical practice. Educators who recognize the power of this tool have sought to incorporate it into the medical school curriculum. The basic question that educators should ask themselves is: “What should a student graduating from medical school know about US?” To aid them in answering this question, US specialists from the Society of Radiologists in Ultrasound and the Alliance of Medical School Educators in Radiology have collaborated in the design of a US curriculum for medical students. The implementation of such a curriculum will vary from institution to institution, depending on the resources of the medical school and space in the overall curriculum. Two different examples of how US can be incorporated vertically or horizontally into a curriculum are described, along with an explanation as to how this curriculum satisfies the Accreditation Council for Graduate Medical Education competencies, modified for the education of our future physicians.

Radiographic imaging for Ilizarov limb lengthening in children.

The Ilizarov method for limb lengthening is rapidly gaining popularity in North America. Use of this new technique has necessitated modifications in radiographic protocol. Initial imaging problems gained from our experience with twenty children are detailed including accurate centering for the plain films, correcting for magnification to accurately measure the distraction gap and the expected radiographic appearance of the regenerate bone. Ultrasonography has potential value in accurately measuring the distraction gap and in imaging the new bone prior to radiographic appearance. Since overly fast distraction inhibits bone formation and overly slow distraction leads to premature consolidation, ultrasound may serve a useful role in the qualitative evaluation of new bone formation in Ilizarov limb lengthening, enabling the orthopedic surgeon to tailor the distraction rate to the particular child.

Effect of furosemide and intravenous normal saline fluid load upon the renal resistive index in nonobstructed kidneys in children

Recent literature has shown that relative to baseline the renal resistive index remains unchanged in nonobstructed kidneys and increases in obstructed kidneys after administration of furosemide. To our knowledge the effect upon the renal resistive index of furosemide administered in conjunction with intravenous normal saline fluid load has not been reported. We evaluated the renal resistive index in 13 nonobstructed kidneys in 8 children 6 to 18 years old before and after furosemide and intravenous normal saline fluid load. The mean resistive index decreased from baseline (mean decrease was 0.06 +/- 0.06 standard deviation), with the observation of a resistive index decrease significant to p < 0.005). It appears likely that the combination of an intravenous normal saline fluid load and furosemide caused the resistive index decrease, since a decrease was not observed with furosemide alone; however, these results cannot exclude the possibility that the resistive index decrease was due to the intravenous normal saline fluid load alone. Nonetheless, these data are important since they may provide the foundation for the development of a pharmacologically challenged Doppler sonographic examination using furosemide and intravenous normal saline fluid load to evaluate better potentially obstructed kidneys.