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M Maizels

Publications and source records attributed to M Maizels.

At least 55 records · Page 3Linked to original sources
PubMed1989

Urosound. In-office ultrasonography for pediatric urology.

Ultrasound has proved to be very accurate in evaluating children with common urologic problems such as renal obstruction and urinary infection and in screening for uropathology among children with siblings known to have urologic disease. The benefits of ultrasound in a pediatric population include diagnostic accuracy, ease of use, absence of radiation exposure, and no risk of adverse reactions to contrast agents. As a consequence, ultrasound has become routine in the evaluation of children with urologic conditions, and its use has been expanded to screening of healthy infants for urinary tract abnormalities. One (1.3 per cent) of 73 otherwise-healthy babies studied had urologic problems severe enough to warrant surgery. Steinhart and associates recommended the routine use of ultrasound in healthy infants, because a significant number of infants harbor silent urinary tract abnormalities that can be detected by ultrasound at a low cost. Obstetricians and other primary-care physicians as well as urologists have incorporated the office use of ultrasound into the care for their patients and thus avoid the inconvenience and difficulties of outside referral. In addition, the clinician as a sonographer occupies a unique position that permits sonographic information to be related directly to the clinical problem. In this review, we have included more than three times the number of patients studied in the initial report. The ease and accuracy of office ultrasound that we described initially have been confirmed by subsequent experience. The urosound examination is indicated for the initial evaluation of patients with voiding symptoms, urine infection, or hematuria, as well as to screen patients with known congenital anomalies, such as hypospadias. Urosound can be employed in the surveillance of children with dysfunctional voiding to measure the completeness of bladder emptying and hydronephrosis. The degree of hydronephrosis in cases of ureteropelvic junction obstruction, megaureters, ectopic ureters, and ureteroceles and that remaining after surgery may be documented by urosound examination. We have found that when the urosound study is abnormal, further diagnostic evaluation is more efficiently planned. Office-based pediatric urologist-operated ultrasound supplements the information elicited from routine history, physical examination, laboratory studies, and other radiologic investigations.

Adolescent↗
PubMed1989

Hypospadias hidden by a complete prepuce.

Nine boys were found to have hypospadias despite the presence of a complete prepuce. The urethral meatus was in the subcoronal position in six boys, the distal shaft position in one boy and on the corona glandis in two boys. Although it is generally thought that boys with hypospadias have a dorsal hooded prepuce resulting from incomplete development of the ventral phallus, we have found hypospadias in boys with complete preputial development. Thus, physicians who perform circumcision should fully retract the prepuce to detect occult hypospadias before completing the procedure. Parents of newborns with hypospadias and a complete prepuce should be told, before circumcision, that preputial tissues may be needed to repair the hypospadias.

Child↗
PubMed1988

Caution in antenatal intervention.

We assessed 18 fetuses who harbored a urinary tract malformation that was diagnosed by antenatal sonography. The antenatal diagnosis corresponded to the postnatal diagnosis in 66 per cent of the cases. We review the course of 6 fetuses who had catheters placed percutaneously to drain dilated urinary tracts that were believed to be caused by posterior urethral valves (5) or an obstructed megaureter (1). Only 2 of these fetuses exhibited valves postnatally. No fetus had any recognized benefit from the antenatal intervention. We found that sonography may not readily differentiate fetuses with hydronephrosis with obstruction from those without obstruction. From this experience we conclude that intervention in pregnancies suspected of harboring a fetus with a malformed urinary tract should be done cautiously. Antenatal sonography is useful to identify the fetus with a dilated urinary tract. This identification permits perinatal specialists to be alerted so that preparations for reconstructive surgery in such cases can be made early postpartum.

Female↗
PubMed1988

Office urologic ultrasound in pediatric patients.

We use office ultrasound to supplement the pediatric urologist's office examination and follow the European model (J. Cukier, personal communication). The study can better serve the child and the family in this setting. We have shown that office ultrasound is an excellent primary screening modality, being both practical and accurate. The portable ultrasound machines now available should permit widespread use of office ultrasonography. However, office studies are not intended to replace studies with the more sophisticated and costly ultrasound machines used in radiology departments, only to complement them. We believe the primary uses of in-office examination in children at present are evaluating for detrusor thickness, residual urine volume, bladder capacity, hydronephrosis, and hydroureter; postoperative follow-up of hydronephrosis; screening for sibling uropathology; screening for occult uropathology in cases of gross hematuria; and study of voiding dysfunction or urinary infection. Experience has taught us that the better we become in performing inoffice ultrasound examinations, the better we use ancillary radiologic tests.

Ambulatory Care↗
PubMed1987

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.

Adolescent↗
PubMed1987

Inhibition of protein glycosylation causes renal dysplasia in the chick embryo.

The pathogenesis of renal dysplasia, a common congenital renal malformation, remains poorly understood. However, the disease is believed to represent failure of normal renal morphogenesis. Recently, it has been demonstrated that a shift in the composition of the extracellular matrix from an interstitial type to a basement membrane type heralds induction of the renal mesenchyme. In addition, 2 agents that inhibit glycosylation of extracellular matrix glycoconjugates, 6-diazo-5-oxonorleucine and tunicamycin, prevent induction of tubules in vitro. To investigate the relationship between failure of tubulogenesis and renal dysplasia experimentally, we used these inhibitors as potential teratogens and examined the resultant effects of the renal distribution of 2 extracellular matrix constituents: laminin, a basement membrane glycoprotein, and fibronectin, an interstitial glycoprotein. We documented the normal shift in the distribution of laminin and fibronectin during tubulogenesis. Fibronectin, prominent in undifferentiated mesenchyme, tended to disappear during development, while laminin appeared in increasing amounts within differentiating tubules. Renal rudiments (7 to 9 days of incubation) were exposed to tunicamycin, 6-diazo-5-oxo-norleucine or control media in vitro and then they were permitted to develop further as grafts in ovo. In 127 surviving grafts those treated at 8 days of incubation for 48 hours most often were dysplastic: 12 of 18 (67 per cent) tunicamycin versus 3 of 16 (19 per cent) control media (p less than 0.025) and 8 of 13 (62 per cent) 6-diazo-5-oxo-norleucine versus 2 of 16 (12 per cent) control media (p less than 0.025). Most rudiments exposed to 6-diazo-5-oxo-norleucine or tunicamycin for only 24 hours at 8 days of incubation or at 7 or 9 days of incubation were not dysplastic. Finally, 4 chick kidneys with induced dysplasia and 2 fresh surgical specimens with dysplasia were stained for laminin and fibronectin with indirect immunofluorescence and all showed abnormal distributions of both glycoproteins. These results support existing theories that dysplasia is the result of a disruption in normal epithelial-mesenchymal interaction during the induction of renal tubules.

Animals↗
PubMed1987

In-office ultrasonography to image the kidneys and bladder of children.

We present the first experience with in-office ultrasonography to further the office evaluation of children with urological problems. Since February 1986 we imaged prospectively the kidneys and bladders of 172 children (100 boys and 72 girls, mean age 6 years) who presented for office evaluation using a portable 5 MHz. real-time linear array scanner. Initially, we gained familiarity with in-office ultrasonography by examining 38 children who presented for evaluation of problems not recognized to be associated with renal malformations (that is undescended testis). In-office ultrasonography showed hydronephrosis in 1 boy with a buried penis that was found later to be owing to ureteropelvic junction obstruction requiring pyeloplasty. Then, in-office ultrasonography was used to supplement the office evaluation of children with a history of urine infection, voiding problems or known malformations of the kidney and/or bladder. The test showed that 12 of 24 children (50 per cent) with a history of urine infection had a thickened detrusor, large bladder capacity with or without residual urine or reduced sensation to void. In-office ultrasonography also showed that 24 of 74 children (32 per cent) with voiding problems had a thickened detrusor, large bladder capacity with or without residual urine, fecal impaction, suspected bladder neck obstruction (which later required internal urethrotomy) or small bladder capacity. In 35 children with known malformations of the urinary tract in-office ultrasonography was useful to assess the progress of hydronephrosis (29) or to clarify the etiology of the hydronephrosis (4). The diagnostic value of this test was evaluated in 98 children in whom enough data were available to compare the results to those of subsequent urography or clinical outcome. In-office ultrasonography had a 98 per cent sensitivity and an 82 per cent specificity rate. We conclude that in-office ultrasonography is a reliable means to identify incomplete bladder emptying in children with urine infection related to dysfunctional voiding, identify detrusor thickening related to the unstable bladder and indicate the likely etiology of hydronephrosis.

Child↗
PubMed1986

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.

Abdominal Muscles↗
PubMed1986

Transplantation of the prepuce to facilitate hypospadias repair in monozygotic twins.

We report a case of free transplantation of the prepuce derived from a monozygotic twin to aid in the reconstruction of penoscrotal hypospadias in his brother. Although monozygotic twins discordant for hypospadias are seen rarely the possibility of preserving and transplanting the prepuce of the unaffected sibling should be considered to facilitate reconstruction of the phallus with hypospadias.

Circumcision, Male↗
PubMed1986

Successful hypospadias repair in infants using brief urinary diversion and watertight neourethral closure.

Since July 1982, 23 children between 10 and 28 months old underwent correction of hypospadias. After chordee was resected the urethral orifice was in the perineum in 3, at the penoscrotal junction in 5, on the proximal or mid shaft in 10 or at the distal shaft in 5. The neourethra was fashioned from a transverse island pedicle of preputial skin for proximal hypospadias or by using Mustarde's technique for distal hypospadias. A perforated silicone tube was left in the urethra and a feeding tube was passed through the lumen of the urethral stent to drain the bladder. Up to 4 days later the bladder catheter was removed and the children voided per the neourethra. The urethral stent was removed between 6 and 30 days postoperatively. Voiding through a recently constructed urethra was well tolerated. The boys did not experience bladder spasms, urinary extravasation did not occur and cosmetic results were good. Meatal stenosis did not occur. Three children (13 per cent) required closure of a fistula, which was noted 1 to 2 1/2 years later. It appears that briefly diverting bladder urine after hypospadias repair ameliorated postoperative morbidity without compromising the results. This technique was found to be inappropriate in older boys because of significant dysuria.

Child, Preschool↗
PubMed1986

Guide to the history in enuretic children.

In evaluating a child with enuresis, an organized approach to the history leads to a working diagnosis and an appropriate treatment plan. Questions are grouped in nine categories: perinatal complications, complications in infancy, toilet training, voiding pattern (assessed with a voiding diary), micturition pattern, urinary infection, defecation pattern, perineal symptoms and food sensitivities. Structural abnormalities must be evaluated cautiously to assure that a functional problem is not overlooked.

Biofeedback, Psychology↗
PubMed1985

Type I ureteral triplication: an extension of the Weigert-Meyer law.

We report a case of type I ureteral triplication and document the locations of the ureteral orifices corresponding to the renal segments. The ureter from the uppermost renal segment issued onto the urethrovaginal septum and caused wetting. The wetting was cured by high ureteroureterostomy. Our findings are consistent with those expected by the Weigert-Meyer law.

Child↗
PubMed1985

Successful treatment of nocturnal enuresis: a practical approach.

In this article, the emphasis is on formulating a correct diagnosis when the symptom of nocturnal enuresis is present, so that an effective treatment plan can be initiated. Diagnosis may relate to structural, urodynamic, psychologic, dietary, nephrologic, or neurologic problems. The authors present the format for successful treatment of nocturnal enuresis used at the Center to Assist the Regulation of Enuresis at the Children's Memorial Hospital in Chicago.

Adolescent↗
PubMed1984

Pitfalls in using human chorionic gonadotropin stimulation test to diagnose anorchia.

Previous studies have concluded that surgical exploration is unnecessary in genetic male subjects with nonpalpable tests who fail to respond to human chorionic gonadotropin. Lack of response suggested absent testicular tissue. We report on 2 patients thought to have anorchia because of lack of response to human chorionic gonadotropin stimulation. Testes were found in both patients. Genetic and phenotypic male subjects with nonpalpable testes who fail to have increased testosterone after human chorionic gonadotropin stimulation should undergo laparoscopy. If testicular structures are present at laparoscopy surgical exploration is indicated. Unresponsiveness to human chorionic gonadotropin may be evidence of nonexistent or dysfunctional Leydig cells rather than evidence of complete absence of testicular tissue.

Child↗