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Biomedical subjects

R L Lebowitz

Publications and source records attributed to R L Lebowitz.

At least 19 recordsLinked to original sources
PubMed2001

Extrinsic ureteropelvic junction obstruction from a crossing renal vessel: demography and imaging.

BACKGROUND: The increase in the use of prenatal ultrasound has revolutionized the detection of hydronephrosis and has had an unanticipated consequence. OBJECTIVE: To describe the new demographics of symptomatic ureteropelvic junction (UPJ) obstruction and the characteristic imaging findings, when the obstruction is extrinsic, from a crossing renal vessel. MATERIALS AND METHODS: From a uroradiology database (1994 through 1999) we identified children with surgically corrected UPJ obstruction from intrinsic and extrinsic causes. RESULTS: One hundred children had symptomatic UPJ obstruction treated by surgery. In 51 (49 %), obstruction was due to a crossing vessel. One hundred and one had UPJ obstruction detected by prenatal sonography. Only 11 (11%) were due to a vessel. Two clinical and imaging findings were strongly suggestive of obstruction from a vessel: (1) in 5 of the 100 children the symptoms (pain, nausea, and vomiting) were intermittent. Only when symptoms were present were there hydronephrosis and obstruction; (2) in 51 of the 100 children a short segment of ureter, just below the UPJ, was filled with contrast or urine (on renal sonography, intravenous urography, or retrograde/antegrade ureterography). CONCLUSIONS: Extrinsic UPJ obstruction caused by a vessel is an uncommon cause of obstruction when all patients are considered. However, in symptomatic older patients whose hydronephrosis was not first identified on prenatal sonography, a vessel was the cause of obstruction in one half.

Child↗
PubMed2001

Predictors for abnormal voiding cystourethrography in pediatric patients undergoing renal transplant evaluation.

The role of pretransplant voiding cystourethrography (VCUG) in adults has been questioned owing to the low prevalence of abnormal findings. As there are no studies evaluating the relevance of VCUG in children and because vesicoureteral reflux (VUR) occurs with higher prevalence in children, we performed a retrospective cohort study to identify any predictors for abnormal VCUG. We reviewed 271 consecutive renal transplants performed between 1980 and 1997. By logistic regression, the etiology of end-stage renal disease (ESRD) and age at transplantation (Tx) were strong predictors of abnormal pretransplant VCUG findings in children. On multi-variate analysis, children with urologic etiologies of renal disease had an odds ratio (OR) of 16.5 (p < 0.0001) for abnormal VCUG as compared to children with non-urologic or acquired causes of ESRD. Similarly, children transplanted when younger than 8 yr of age had an OR of 3.0 (p = 0.0043) for having an abnormal VCUG when compared with older children. Finally, our analysis suggests that children with abnormal pretransplant VCUG findings, whether or not pretransplant surgical correction was performed, were over three-fold more likely to require post-transplant urologic surgery when compared to children with normal pretransplant VCUG. We conclude that urologic causes of ESRD and age under 8 yr are strong independent predictors of abnormal pretransplant VCUG findings, and that these findings are of clinical relevance both in deciding whether to pursue pretransplant VCUG and in the post-transplant course of the patient.

Adolescent↗
PubMed2000

Pediatric radiologists: who we are and what we do. Results of a membership survey of the Society for Pediatric Radiology--1999.

BACKGROUND: There is a need for reliable monitoring of workforce trends in the field of pediatric radiology by the Society for Pediatric Radiology. In addition, the Society should periodically assess itself as to its mission and relevance to its members via membership surveys. OBJECTIVE: The Membership Committee of the Society for Pediatric Radiology, 1999, conducted a 54-question survey to determine the makeup of its members, job profiles, satisfaction with services of the Society for Pediatric Radiology, and its official journal, Pediatric Radiology. MATERIALS AND METHODS: Seven hundred fifty surveys were given to active members of the Society for Pediatric Radiology in the United States and Canada. There were 275 surveys returned for an overall response of 37%. RESULTS: Mean age of members is 48 years with 99% of respondents working. Membership is 34% female and 66% male. Women members of the Society are younger (45 vs 49 years, P = 0.0012) and work less hours (47.8 vs 51.0, P = 0.0135) than men. Fifty-seven percent of respondents practice in a freestanding children's hospital, 29% in a "children's hospital within a hospital," and 14% are in community hospitals or an office-based practice. Eighty-two percent of the responding pediatric radiologist's time is spent in performing examination on children, with only 18% spent on adult work or administration. Forty-eight percent work at more than one office. Sixty-one percent worked evenings or weekends, excluding night call. Two hundred twenty-two of 275 respondents had received a Certificate of Added Qualification. The meeting "for CME credit" was considered the most important benefit of Society membership. Most respondents read select articles in Pediatric Radiology. There was sentiment to decrease esoteric case reports in favor of review articles. Only 19% of respondents submitted their articles to Pediatric Radiology initially. CONCLUSION: Pediatric radiologists are a diverse membership with the common goal of advocating for healthcare and imaging in children. Survey information given to the leadership of the Society will help the organization remain responsive to its members.

Adult↗
PubMed1998

Incontinence due to an infrasphincteric ectopic ureter: why the delay in diagnosis and what the radiologist can do about it.

PURPOSE: To determine (1) the reasons for the frequently long delay in the diagnosis of an infrasphincteric ectopic ureter in girls, and (2) what role the radiologist can play in decreasing the delay. MATERIALS AND METHODS: Twelve girls were referred to our hospital from June 1994 until April 1997 for evaluation of constant urinary dribbling and/or vaginal discharge. Available imaging studies, radiology reports, and clinic notes were reviewed. RESULTS: Mean age at the time of diagnosis was 6 years 7 months (range 2 years 10 months to 11 years 11 months). Mean delay until diagnosis after presentation was 2 years 5 months. Excluding the one girl whose ectopic ureter was diagnosed while she was still in diapers, mean age at the time of the first parental "complaint" was 4 years 9 months. The significance of the classic history of constant urinary dribbling was not recognized by physicians in 7 girls for 4 months to 7 years 10 months after presentation. Physical exam was not meticulously performed, as the ectopic orifice was visible in 8 of 12 girls. Imaging studies were ineffectively utilized: no imaging was done (for 2 years in 2 girls), inappropriate studies were done (ultrasound and voiding cystourethrography) and were misleading, studies were called normal when they were not (ultrasound and excretory urography), or perinatal imaging led to the incorrect assumption of a congenitally absent kidney in one girl and a multicystic dysplastic kidney in another. Excretory urography (EU) was diagnostic in all 10 girls with a duplex kidney, and computed tomography (CT) was supportive in 2 with a dysplastic kidney. CT was an adjunct in 3 girls; a Tc-99m-dimercaptosuccinic acid (DMSA) scan was needed in 2. CONCLUSION: The classic history of constant urinary dribbling in a successfully toilet-trained girl should immediately lead to an imaging search for the portion of kidney (or entire kidney) drained by an infrasphincteric ectopic ureter. EU should usually be the first imaging performed and is often the only imaging study needed.

Child↗
PubMed1997

Correlation of cystographic bladder morphology and neuroanatomy in boys with posterior urethral valves.

PURPOSE: We have observed a difference in the radiographic appearance of the body of the bladder (trabeculated) and its base (smooth) in boys with severely obstructing posterior urethral valves. We wanted to determine if (1) this was a reproducible finding and (2) there was an anatomic and/or physiologic explanation for it. MATERIALS AND METHODS: We reviewed the initial voiding cystourethrogram in 47 boys with severe posterior urethral valves. The interureteric ridge was used as the division between the body and base of the bladder. The presence of trabeculation for each region was recorded. RESULTS: Ages ranged from 1 day to 6 years at the time of initial cystographic evaluation (median 14 days). The body of the bladder was trabeculated and the base smooth in 72 % (34 patients). In the remaining patients, both the body and base were smooth. In no patient was the base trabeculated. CONCLUSIONS: The cystographic morphology of the urinary bladder in boys with posterior urethral valves can be explained by its neuroanatomy. The body of the bladder, which contracts during voiding because of parasympathetic (cholinergic) stimulation, becomes trabeculated. The bladder base relaxes during voiding due to sympathetic (alpha adrenergic) stimulation and remains smooth. Thus, this difference in the cystographic appearance of the two parts of the urinary bladder reflects the normal innervation and the mechanics of micturition in boys with urethral obstruction.

Child↗
PubMed1996

Absence of a renal sinus echo complex in the ectopic kidney of a child: a normal finding.

The typical urographic and anatomic appearance of the extrarenal pelvicalyceal system of the normal ectopic kidney has been thoroughly described. We report the ultrasonographic correlate of this distinct configuration. The normal central renal sinus echo complex was absent in two thirds of the ectopic kidneys in this series. In the remaining one third, the sinus echo complex was eccentric.

Adolescent↗
PubMed1995

Congenital urethroperineal fistula.

PURPOSE: To characterize the radiographic appearances of congenital urethroperineal fistula and to distinguish it from urethral duplication of the hypospadiac type. MATERIALS AND METHODS: The authors examined four patients with congenital urethroperineal fistula in whom radiographic examinations were performed to define the pathologic anatomy. RESULTS: Congenital urethroperineal fistula mimics the hypospadiac form of urethral duplication, except the normally positioned dorsal channel is the normal urethra. Patients with congenital urethroperineal fistula have normal micturition. Both a normal dorsal penile urethra and a ventral urethroperineal fistula can be observed during radiographic and cystoscopic examination. The dorsal urethra is the functionally normal channel. Excision of the ventral channel is simple and curative. This contrasts starkly with congenital urethral duplication of the hypospadiac type, where excision of the ventral channel may be catastrophic. CONCLUSION: Although it resembles the hypospadiac form of urethral duplication, congenital urethroperineal fistula should be classified as a separate entity.

Adolescent↗
PubMed1995

Complete duplication of the ureter with ureteropelvic junction obstruction of the lower pole of the kidney: imaging findings.

OBJECTIVE: The purpose of our study was to identify the radiographic signs that aid in the diagnosis of obstruction of the ureteropelvic junction of the lower pole (or moiety) of the kidney in children with complete duplication of the ureter and to describe the imaging appearance of this unusual cause of lower-pole hydronephrosis. MATERIALS AND METHODS: We reviewed the medical records and imaging studies of 16 children (11 boys and five girls) with complete ureteral duplication and ureteropelvic junction obstruction of the lower pole of the kidney over a 5-year period. standard criteria for determining urinary tract obstruction were used. RESULTS: Sonograms showed a lower-pole abnormality (hydronephrosis or cystic mass) in all 15 children who underwent sonography. Voiding cystourethrography, performed for all children, showed vesicoureteral reflux into the lower pole in addition to ureteropelvic junction obstruction in eight children (seven boys and one girl). For the other eight, the diagnosis of lower-pole ureteropelvic junction obstruction was made by excretory urography, at times complemented with diuretic renography or retrograde ureterography. CONCLUSION: Ureteropelvic junction obstruction of the lower pole of the kidney in children with complete duplication of the ureter should be a diagnostic consideration when there is dilatation of the lower moiety. Imaging changes parallel those of ureteropelvic junction obstruction in a nonduplicated system. This anomaly, unlike others seen in duplication, appears to be more common in boys than in girls.

Child↗
PubMed1995

Detection of a poorly functioning malpositioned kidney with single ectopic ureter in girls with urinary dribbling: imaging evaluation in five patients.

OBJECTIVE: Some girls with lifelong continuous dribbling of urine despite successful toilet training have urographic or sonographic evidence of only one kidney. Such girls are likely to have a contralateral, poorly functioning, nonvisualized, malpositioned kidney with a nonduplicated collecting system and ureter draining through an ectopic orifice. Our objective was to analyze our experience with this group of patients to determine how best to confirm the presence and show the location of this abnormal kidney. MATERIALS AND METHODS: We reviewed the medical records and imaging studies of five such girls who were first seen at our hospital between 1975 and 1993 to determine how their poorly functioning, malpositioned kidney was detected. The imaging studies included sonography, excretory urography, vaginography, retrograde and intraoperative antegrade ureterography, renal cortical scintigraphy using 99mTc-dimercaptosuccinic acid, CT, and MR imaging. RESULTS: All the abnormal kidneys were located on the left side. Excretory urography and sonography showed the abnormal kidney in only one of these five patients. In a second girl, retrograde ureterography showed the ureter of the dysplastic kidney after an ectopic ureteral orifice was discovered in the vagina during examination under general anesthesia. In a third, reflux from the vagina during a vaginogram showed the abnormal kidney. Renal cortical scintigraphy using dimercaptosuccinic acid showed the dysplastic, malpositioned, poorly functioning kidney in three girls. CT with special attention to the region of radionuclide uptake seen on scintigram showed the location of the dysplastic kidney more precisely in two patients. CONCLUSION: A girl with continuous dribbling of urine despite normal voiding habits whose excretory urogram and sonogram reveal only one kidney should have a dimercaptosuccinic-acid scintigram as the next imaging evaluation. A CT scan through the area of interest as determined by the dimercaptosuccinic-acid scintigram will more accurately localize the often ectopic kidney, thus facilitating its removal.

Adolescent↗
PubMed1994

Acute pyelonephritis: can we agree on terminology?

There is no general agreement on which terms to use to report abnormalities on imaging studies in patients with kidney infection. The Society of Uroradiology recommends a simplified nomenclature that is based on the traditional and widely understood term acute pyelonephritis. To provide a framework for the simplified terminology, the authors review the relevant pathophysiology with its imaging correlates and offer a historic perspective on the terminology issues.

Acute Disease↗
PubMed1994

Benign cystitis in children mimicking rhabdomyosarcoma.

Seventeen (13 male, 4 female) patients, aged 13 months to 13 years, with benign cystitis had imaging findings that mimicked those of rhabdomyosarcoma. Our experience indicates that in the child with hematuria, dysuria, and frequency plus cystographic or sonographic demonstration of a bladder with reduced capacity and circumferential wall thickening or sonographic findings of isoechoic bladder wall thickening (focal, multifocal or circumferential distribution), intact mucosa, and bullous lesions should strongly suggest inflammation and not malignancy. When an inflammatory lesion is suspected, follow-up imaging should be performed in 2 weeks, which if normal will preclude biopsy.

Adolescent↗