Max Maizels

Ultrasound grading of hydronephrosis: Introduction to the system used by the society for fetal urology

The Society for Fetal Urology (SFU) was founded in 1988 to study the postnatal evolution of prenatally detected anomalies of the urinary tract by following those neonates whose prenatal studies have brought them to medical attention while asymptomatic. The SFU has attempted to standardize methods of performing and grading the ultrasound and radionuclide examinations in this population. A system to grade upper tract dilatation or hydronephrosis (HN) imaged by ultrasound has been developed and is being used by SFU members in 36 institutions. The appearance of the calices, renal pelvis and renal parenchyma are key in determining the grade of HN and are illustrated in this article.

SURGERY VERSUS OBSERVATION FOR MANAGING OBSTRUCTIVE GRADE 3 TO 4 UNILATERAL HYDRONEPHROSIS: A REPORT FROM THE SOCIETY FOR FETAL UROLOGY

PURPOSE The Society for Fetal Urology has undertaken the first multicenter prospective randomized study of high grade obstructive unilateral hydronephrosis to evaluate the natural history of untreated obstruction and compare it to the benefits of pyeloplasty. MATERIALS AND METHODS Since 1991, infants with isolated unilateral Society for Fetal Urology grade 3 hydronephrosis and ipsilateral obstruction with greater than 40% differential renal function on well tempered renography were studied. Patients were randomly assigned to observation or pyeloplasty groups. Renal ultrasound and well tempered renography were performed biannually for 1 year and yearly thereafter. Crossover criteria for surgery included concurrent worsening of isotope washout and increasing grade of hydronephrosis or a greater than 10% point loss in percent differential renal function that was noted between studies. The end point of the study was the 3-year anniversary of randomization. RESULTS A total of 32 infants from 10 centers were randomized equally to 2 groups. The starting grade of hydronephrosis and percent differential renal function were similar between the 2 groups. At 6 months and 1 year the grade of hydronephrosis was significantly reduced (p < 0.02) and well tempered renography was significantly more likely to demonstrate no obstruction (p < 0.03) in the surgical group compared with the observation group. The mean percent differential renal function remained stable and similar in both groups. Reduced hydronephrosis and resolution of obstruction in the surgery group persisted as a trend at the 2 and 3-year anniversaries. In the observation group 4 patients (25%) showed enough renal deterioration to qualify for crossover to surgery. CONCLUSIONS Infant pyeloplasty significantly improved the grade of hydronephrosis and drainage pattern at 6 months and 1 year postoperatively, when compared with observation. Renal function stabilization was similar for either management approach. However, 25% of the patients satisfied objective criteria of status deterioration requiring pyeloplasty.

Bladder Capacity (Ounces) Equals Age (years) Plus 2 Predicts Normal Bladder Capacity and Aids in Diagnosis of Abnormal Voiding Patterns

Standardization of the bladder capacities of children will improve the precision of urodynamic evaluation. In an attempt to develop a practical guide to predict the normal bladder capacity during childhood the bladder capacities of 132 children without a clinically abnormal pattern of voiding were measured. When the bladder capacities are correlated by age the following linear relationship exists: normal bladder capacity (ounces) equals age (years) plus 2. The bladder capacities of 68 children with primary enuresis, frequency or infrequent voiding were then measured. Children with clinically infrequent voiding demonstrated large bladder capacities and those with frequency or enuresis demonstrated small bladder capacities compared to normal children. The formula appears to be a useful guide to predict normal bladder capacity by age and also to aid in the diagnosis of abnormal voiding patterns.

Surgical Correction of the Buried Penis: Description of a Classification System and a Technique to Correct the Disorder

The concealed penis is a long-standing problem that only recently has begun to receive the attention it deserves. We offer a classification for this general disorder, which facilitates the selection of appropriate surgical procedures for these patients. To correct the most common problem, the buried penis, involves removal of localized deposits of fat from the hypogastrium with open surgical or closed suction techniques followed by anchoring of the skin of the base of the penis to the periosteum of the pubis. During the last year we have used this approach successfully in 7 boys with various forms of penile concealment with good results.

Grading nephroureteral dilatation detected in the first year of life: correlation with obstruction.

To understand better the significance of pediatric idiopathic nephroureteral dilatation the renal ultrasound images of patients less than 1 year old with hydronephrosis or hydroureteronephrosis were graded and compared to the radiological diagnosis of obstruction as determined by diuresis renography and/or urography. The study included 73 boys and 30 girls with hydronephrosis (76 patients) or hydroureteronephrosis (27). For hydronephrosis obstruction was diagnosed in 56 children (74%) and involved 61 of 97 kidneys (63%). For obstructed kidneys the mean grade of hydronephrosis (3.4 +/- 0.7 standard deviation) was statistically different from that of nonobstructed kidneys (1.6 +/- 0.8 standard deviation) (p less than 0.05). When the value to predict obstruction was set at grade 3 hydronephrosis or greater there was an 88% sensitivity and 95% specificity. For hydroureteronephrosis obstruction was diagnosed in 15 of 27 children (56%) and involved 17 of 34 kidneys (50%). The degree of dilatation was weighted as a score to assess the grades of hydronephrosis and ureteral dilatation, namely hydroureteronephrosis score equals grade of hydronephrosis plus grade of ureteral dilatation. In obstructed megaureters the mean hydroureteronephrosis score (5.8 +/- 1.0) was statistically different from that for nonobstructed megaureters (mean hydroureteronephrosis score 2.7 +/- 1.9) (p less than 0.001). When the value to predict obstruction was set at hydroureteronephrosis score of 5 or greater there was a 94% sensitivity and 80% specificity. Although ultrasound examination alone cannot be used to diagnose urinary obstruction, the radiological diagnosis of obstruction is linked with the grade of hydronephrosis or score of hydroureteronephrosis.

Decreased incidence of bacteriuria associated with periodic instillations of hydrogen peroxide into the urethral catheter drainage bag

We determined the incidence and source of bacterial colonization of the bladder in 31 consecutive patients with acute spinal cord injury who required indwelling urethral catheterization. Patients were randomized to conventional drainage or to conventional drainage with a secondary sterile bag for periodic administration of saline or 3 per cent hydrogen peroxide. The hydrogen peroxide group maintained sterile bladder urine significantly longer than the conventional drainage group (p less than 0.05). Cultures suggested that the reservoir for bladder colonization was the bag in 5 of 12 patients (42 per cent) on conventional drainage. Instillation of hydrogen peroxide prevented bacterial contamination of the drainage bag before bladder bacteriuria (p less than 0.01) and also reduced drainage bag bacteriuria in patients with urinary infections (p less than 0.0005). The data indicate that bacterial contamination of the drainage bag is a frequent source of bladder bacteriuria that can be eliminated effectively by periodic instillation of hydrogen peroxide.

Detrusorrhaphy: Extravesical Ureteral Advancement to Correct Vesicoureteral Reflux in Children

We used a modified extravesical technique, coined detrusorrhaphy, to correct surgically vesicoureteral reflux. By detrusorrhaphy the submucosal ureteral tunnel is opened, the ureteral meatus is advanced and anchored onto the trigone, and the detrusor buttress of the ureter is closed (-rrhaphy). The operation is performed extravesically. The procedure was used in the last 5 years in 79 children, or 120 renal units. Reflux resolved in 93 per cent of the renal units. Postoperative morbidity related to bladder spasms and hematuria was minimal compared to conventional transvesical surgical procedures. Detrusorrhaphy is an effective method to correct vesicoureteral reflux and to minimize postoperative morbidity.

Cowpek’s Syringocele: A Classification of Dilatations of Cowper’s Gland Duct Based Upon Clinical Characteristics of 8 Boys

Lesions of Cowpers gland duct assume various appearances. A system to classify each of these appearances is offered to diagnose these lesions more precisely. The urethrographic and endoscopic characteristics of dilated Cowpers gland ducts noted in 8 boys are grouped as a simple classification. The dilated Cowpers duct is referred to as a syringocele (Greek syringo--tube plus cele--swelling). There are 4 groups of Cowpers syringoceles: 1) simple syringocele--a minimally dilated duct, 2) perforate syringocele--a bulbous duct that drains into the urethra via a patulous ostium and appears as a diverticulum, 3) imperforate syringocele--a bulbous duct that resembles a submucosal cyst and appears as a radiolucent mass, and 4) ruptured syringocele--the fragile membrane that remains in the urethra after a dilated duct ruptures. Marsupialization of the syringoceles cured urine infection and hematuria but voiding symptoms may persist.

Urodynamic Biofeedback: A New Approach to Treat Vesical Sphincter Dyssynergia

Some children with vesical sphincter dyssynergia are refractory to conventional pharmacologic therapy. Three such patients were treated using a method of sphincter retraining, biofeedback. They observed the urinary sphincter electromyogram while voiding to appreciate visually the abnormality. Two children learned to suppress voluntarily the inappropriate sphincter contraction during voiding. This normalized the subsequent electromyographic recordings and offered subjective improvement in the voiding symptoms. Retraining the urethral sphincter dysfunction may be approached using biofeedback techniques in selected patients.

THE PRENATAL DIAGNOSIS OF CLOACAL EXSTROPHY

PURPOSE We assess and clarify diagnostic features for making the prenatal diagnosis of cloacal exstrophy. MATERIALS AND METHODS We evaluated 9 patients born with cloacal exstrophy at our institutions (2 prospectively and 7 retrospectively) for diagnostic features on prenatal ultrasound studies. We also thoroughly reviewed the literature on 13 previous prenatally diagnosed cloacal exstrophy cases. Diagnostic criteria were assessed by combining the findings in our patients and those in previous reports. RESULTS Of the 22 patients with prenatal ultrasound studies and cloacal exstrophy whom we analyzed 1 of our 9 and 2 in the literature had a cloacal membrane that persisted at 22 weeks of gestation. Major ultrasound criteria for diagnosing cloacal exstrophy prenatally are nonvisualization of the bladder, a large midline infraumbilical anterior wall defect or cystic anterior wall structure (persistent cloacal membrane), omphalocele and lumbosacral anomalies. Seven less frequent or minor criteria include lower extremity defects, renal anomalies, ascites, widened pubic arches, a narrow thorax, hydrocephalus and 1 umbilical artery. CONCLUSIONS We propose major and minor criteria to assist in the prenatal diagnosis of cloacal exstrophy. Despite these major and minor criteria the certainty of establishing a prenatal diagnosis remains challenging. Persistence of the cloacal membrane beyond the first trimester in 1 patient was an exception to the classic concept of cloacal exstrophy embryogenesis. An accurate prenatal diagnosis requires validation of these criteria by further correlation of prenatal and postnatal observations.