Comprehensive analysis of tubularized incised-plate urethroplasty in primary and re-operative hypospadias.

OBJECTIVE: To retrospectively review our experience of the tubularized incised-plate (TIP) urethroplasty over the last 4 years. PATIENTS AND METHODS: From 1998 to December 2001, 133 patients (mean age 7 years, sd 4, range 1-22), had a TIP urethroplasty by one surgeon for primary (103) and re-operative (30) hypospadias; the defects included 106 (79%) distal and mid-shaft, and 27 (21%) posterior shaft. The neourethra was covered by a subcutaneous flap in 66 (50%) patients or by corpus spongiosa (spongioplasty) in 31 (23%), with no cover in the remaining 36 (27%). In the last 20 patients (15%) a modified meatoplasty was used; the site and size of the new meatus was predetermined on the glans around a suitable catheter before any incision. Urethral stents were not used after repair in 39 (29%) patients, and regular meatal dilation was used only in patients with voiding difficulty and obvious tendency to stenosis. The presence of complications requiring re-operation and overall general appearance were recorded. RESULTS: The mean (sd) follow-up was 10 (5) months; there were 24 complications in 20 patients (15%), including a small fistula in 12 (9%), complete disruption of the repair in 4 (3%), meatal stenosis in seven (5%) and neourethral stricture in one (0.8%). Complications were not significantly different between primary and re-operative cases, and unaffected by the use of the stents. On univariate analysis complications were significantly higher with running than interrupted sutures, in repairs in the first 2 years of the study, in patients with posterior hypospadias, and in those with no neourethral coverage. However, the last two factors were the only significant independent risk factors in a multivariate analysis. Regular urethral dilatation was indicated in 43 patients (32%). Modified meatoplasty was associated with a significantly lower requirement for regular dilatation (P < 0.05) and no meatal stenosis. In the 113 complication-free patients the operation gave an excellent cosmetic appearance with a vertical slit meatus on the tip of conical glans in 110 (97%); there was slight meatal retraction in the remaining three patients. CONCLUSION: The TIP repair is a reliable method for treating both distal and proximal penile shaft hypospadias, is suitable for both primary and re-operative cases, and is more versatile than other repairs. Covering the neourethra with a flap or spongioplasty significantly improves the results. Regular urethral dilatation is required in a third of patients but modified meatoplasty obviates the need for regular dilatation and eliminates the risk of meatal stenosis.

Treatment of urethral defects: skin, buccal or bladder mucosa, tube or patch? An experimental study in dogs.

PURPOSE: We studied 3 graft materials and 2 urethroplasty techniques in 24 adult male mongrel dogs. MATERIALS AND METHODS: The animals were divided into 2 equal groups. In group 1 a 4 cm. segment of perineal urethra was excised and tubed urethroplasty was performed using free full-thickness skin, buccal and bladder mucosa grafts in 4 dogs each. In group 2 a 4 cm. urethral strip was excised and onlay urethroplasty was performed using the same graft materials in 4 dogs each. Retrograde urethrography was done and the animals were sacrificed at week 12. Autopsy specimens were calibrated with a 10Fr catheter. Hematoxylin and eosin stained sections were examined. Masson's trichrome stain was used to determine the extent of fibrosis. RESULTS: Urethral stricture was diagnosed by radiology and confirmed by calibration in 8 of the 12 dogs (66%) in group 1 but in only 1 of the 12 (8%) in group 2 (p <0.004). Buccal mucosa grafts were associated with the lowest stricture rate of 12%, followed by 37% for bladder mucosa and 62% for skin (p <0.2). There was no difference in neovascularization among the 3 grafts. Graft shrinkage was less than 10% for buccal mucosa compared with 20% to 40% for skin and bladder mucosa. The shrinkage rate was similar for the onlay and tube techniques. The intensity of chronic inflammation and fibrosis was highest in the skin grafts. Circumferential fibrosis was noted in association with tubed urethroplasty but not with the onlay technique. CONCLUSIONS: The theoretical advantages of buccal mucosal grafts were pathologically demonstrated. When possible, grafts should be used as an onlay rather than as a complete tube.

Long-term outcome analysis of low pressure rectal reservoirs in 33 children with bladder exstrophy.

PURPOSE: The augmented valved rectum and double folded rectosigmoid bladder represent 2 modifications of ureterosigmoidostomy. Both procedures improve continence by lowering the reservoir pressure. We present the outcome of these techniques on the upper urinary tract, continence, metabolic profile, linear growth and bone density. MATERIALS AND METHODS: Between March 1987 and May 1997, 22 boys and 11 girls with bladder exstrophy underwent urinary diversion to a low pressure rectal reservoir. Patient age at surgery ranged from 2 to 13 years (mean 5.4). The augmented valved rectum technique was used in 18 cases and the double folded rectosigmoid bladder method was used in 15. Serial followup ultrasounds were obtained and voiding proctography was performed 1 year postoperatively in all patients. Supine height was measured at last followup in all cases. Serum electrolytes, arterial blood gases, the results of which were plotted on an acid base nomogram, and bone density using dual energy x-ray absorptiometry were measured in all patients. Prophylactic alkalization was administered to all patients. RESULTS: Mean followup is 66 months (range 24 to 148). All patients are continent during the daytime with an emptying frequency of 3 to 5 times, and all are continent at night. No patient experienced pyelonephritis or clinical acidosis. The upper urinary tract was either improved or stabilized in 64 of 66 renal units. No patient had reflux to the upper urinary tract. All patients had normal serum creatinine, sodium, potassium, calcium and phosphorus. Hyperchloremia was noted in 19 of the 33 patients (57%), and arterial blood gases showed subclinical metabolic acidosis in 18 (55%). Supine height measurements at last followup revealed that 19 of the 33 patients (57%) had decreased linear growth (below 3rd percentile). All patients had significant reduction in bone density, and mean for age corrected bone density was 70% (standard deviation 10.9%). Both groups (augmented valved rectum and double folded rectosigmoid bladder) were comparable in regard to age, sex and followup duration. There was no statistically significant difference between the groups in any parameter measured. CONCLUSIONS: The augmented valved rectum and double folded rectosigmoid bladder provide preservation of the upper urinary tract with excellent continence rates. However, prophylactic alkalization and functional isolation of the reservoir do not prevent the long-term metabolic consequences. Subclinical metabolic acidosis and decreased linear growth are to be anticipated in more than 50% of patients. Moreover, significant bone demineralization is to be expected in all of these patients.

Cystolitholapaxy versus cystolithotomy in children.

BACKGROUND: Primary vesical stones are common in children in developing countries. Cystolithotomy is the traditional treatment, but a percutaneous approach has been advocated. PATIENTS AND METHODS: Between January 1992 and March 1997, 52 male children with primary vesical stones were treated at our center. The patients were stratified retrospectively into two groups according to the procedure of stone removal. Group I (25 patients) were children who underwent open cystolithotomy, and group II (27 patients) were those who had endourologic treatment either by the transurethral route (11 children) or via suprapubic approached (16). The mean age at the time of diagnosis was 3.6 +/- 2.1 years. The stone size ranged from 0.7 to 2 cm (mean 1.2 +/- 0.7 cm). RESULTS: In all cases, the stones were removed successfully. The operative time was similar in the two groups. The hospital stay was significantly less after endourologic procedures than after open surgery (P < 0.05). In Group I, one patient had a small-intestinal injury, and in Group II, one patient had urethral rupture and extravasation during transurethral cystolitholapaxy. There were no early or late complications in Group I. However, in Group II, 4 patients (15%) developed early and late complications. Early morbidity was in the form of persistent leakage of urine from the suprapubic site in one patient and acute abdomen from the peritoneal urine leakage in another two patients who had the same approach. A stricture of the bulbous urethra was seen in one patient 1 year after transurethral stone disintegration. CONCLUSION: In spite of the improvement of endourologic instruments, open surgical removal of primary vesical stones in boys is still the mainstay of therapy.

Evaluation of the functional significance of the colorectal valve used in rectal urinary diversion in children: a comparative study between cases with and without the valve.

OBJECTIVES: To study the long-term impact of functional isolation of rectal reservoirs on the blood chemistries and acid-base balance of children who underwent this type of urinary diversion. METHODS: A retrospective evaluation of 63 children with rectal reservoirs was performed. Of these, 40 had a colorectal valve and 23 had double-folded rectal reservoirs without a functional isolation valve. Evaluation included serum chemistry and arterial blood sample analysis to verify the impact of the created valve on homeostasis. RESULTS: There was a statistically significant difference between the two groups relative to the value of pH, P(CO2), bicarbonate, base excess, and chloride in favor of those having a colorectal valve. Reduction of the absorptive surface area of the colon is presumably the cause in view of the functional isolation created by the colorectal valve. CONCLUSIONS: In children, the long life expectancy and the benign condition for which they have diversion require the incorporation of the colorectal valve in any form of continent rectal diversion. Prophylactic alkalinization with strict follow-up is a must in those having no valve.

Renal Doppler ultrasonography in children with equivocal obstructive uropathy: effect of intravenous normal saline fluid load and frusemide.

OBJECTIVE: To study the effect of hyperhydration with normal saline and frusemide on the renal resistive index (RI) in children with equivocal obstructive uropathy. PATIENTS AND METHODS: Twelve children (24 kidneys) with unilateral or bilateral hydronephrosis underwent isotopic diuretic renography and Doppler ultrasonography. All children had equivocal obstruction of the hydronephrotic kidneys with half-time drainage (T/2) values of 10-20 min. Doppler studies were carried out both at baseline and after the infusion of normal saline and frusemide. RESULTS: Of the 24 kidneys, five were normal and 19 were hydronephrotic; compared with normal kidneys, the hydronephrotic units had a significantly lower glomerular filtration rate (GFR) and longer T/2. At baseline, the mean RI values of normal and hydronephrotic kidneys were not significantly different (0.70, SD 0.03 and 0.71, SD 0.04, respectively). After the infusion of saline and frusemide, the mean RI of hydronephrotic kidneys (0.67, SD 0.07) was significantly (P = 0.01) higher than that of normal kidneys (0.60, SD 0.02), but the response of RI in hydronephrotic kidneys was variable. Based on the RI at baseline and after infusion, hydronephrotic kidneys could be categorized into three groups. Group 1 (n = 6) had an RI < 0.7 before and after infusion, group 2 (n = 6) had a baseline RI > 0.7 and < 0.7 after infusion, and in group 3 (n = 7) both RIs were > 0.7. Kidneys in group 3 had the lowest GFR and the highest T/2 values. Five of these seven hydronephrotic kidneys eventually had deteriorating GFRs requiring surgical correction; the GFR of the remaining hydronephrotic kidneys remained stable. CONCLUSION: In children with equivocal obstructive uropathy based on diuretic renography, the determination of RI before and after infusion of normal saline and frusemide could be helpful in distinguishing obstructed from non-obstructed kidneys.

Renal Doppler ultrasound in children with obstructive uropathy: effect of intravenous normal saline fluid load and furosemide.

PURPOSE: We studied the effect of hyperhydration with normal saline and furosemide on renal resistive index in children with obstructive uropathy. MATERIALS AND METHODS: 99mTechnetium-mercaptoacetyltriglycine diuretic renography and Doppler ultrasound were done in 27 children (54 renal units) with unilateral or bilateral hydronephrosis. Doppler studies were performed at baseline, and after infusion of normal saline and administration of furosemide. Half-time drainage, considered the gold standard for the diagnosis of renal obstruction, was compared to resistive index. RESULTS: There was a positive correlation between half-time and resistive index on both Doppler studies. With a resistive index of 0.70 as the critical value for predicting renal obstruction 82 versus 100% sensitivity (p < 0.006), 63 versus 94% specificity (p < 0.04) and 76 versus 98% overall accuracy (p < 0.0005) were obtained for Doppler studies at baseline and after induced diuresis, respectively. All children with false-positive results were younger than age 4 years. CONCLUSIONS: Doppler ultrasonography after hyperhydration with normal saline and furosemide is an accurate method for diagnosing renal obstruction in children. It is more sensitive, specific and accurate than baseline Doppler studies.

Renal Doppler ultrasound in children with normal upper urinary tracts: effect of fasting, hydration with normal saline, and furosemide administration.

OBJECTIVES: To study the age dependency of renal resistive index (RI) and to study the effect on the renal RI of fasting, intravenous infusion of normal saline, and administration of furosemide in children with normal upper urinary tracts. METHODS: The study included 28 nonobstructed renal units in 15 boys ranging in age from 3 to 11 years. Diuretic renography and Doppler ultrasonography were attempted in all children. Doppler ultrasonography was carried out under three different conditions: fasting state, 30 to 60 minutes after intravenous infusion of normal saline (15 mL/kg), and 10 minutes after administration of furosemide (1 mg/kg; maximum, 40 mg). RESULTS: There was an inverse correlation between age and RI of both renal units under the three conditions of Doppler studies. At fasting state mean RI was 0.70 +/- 0.04, whereas 15 of 28 renal units (54%) had an RI of 0.70 or higher. Intravenous infusion of normal saline significantly decreased the RI to 0.63 +/- 0.04 (P < 0.000001). Injection of furosemide caused a further significant decrease of RI from 0.63 +/- 0.04 to 0.60 +/- 0.04 (P < 0.002). CONCLUSIONS: The renal RI in healthy children is age dependent. In the fasting state, 54% of nonobstructed renal units in children have an RI of 0.70 or higher. Intravenous infusion of normal saline and administration of furosemide can independently cause a significant decrease of the RI in nonobstructed renal units in children.

The modified rectal bladder in children: long-term follow-up.

The criteria for evaluation of urinary diversion procedures in children must be strict since their life expectancy is long. Our experience with the modified rectal bladder in children with considerable follow-up periods is reported herein. All patients were continent by day and night. Urography studies revealed a normal upper tract in all cases. Three early complications were encountered among patients who had a submucous tunnel reimplantation. Reflux to the proximal colon or the kidneys was not demonstrated. The metabolic status and growth-rate patterns of these patients were within normal limits without alkaline therapy. All urine samples aspirated from the renal pelves were sterile. We conclude that a modified rectal bladder with a second ileal intussusception valve is the operation of choice whenever urinary diversion in children is indicated.

Prostatic abscess in a child.

We report a metastatic prostatic abscess in a 12-year-old boy. Rectal examination revealed a tender, fluctuating prostatic mass, causing acute retention of urine. Prostatic imaging by computerized tomography and transrectal ultrasonography were important in the diagnosis and management.

Urethral controlled bladder substitution: a comparison between Parks S pouch and hemi-Kock pouch.

To study the effect of the configuration of ileal reservoirs on the urodynamic features, 12 S bladders and 12 Kock pouches were compared. Volume capacity and pressure characteristics were studied 6 months postoperatively. The mean capacity of the reservoirs was 500 +/- 83 ml. for the S bladder and 536 +/- 56 ml. for the Kock pouch. The amplitudes of phasic contractions at 50%, 80% and 100% capacity were similar in both groups. However, the frequency of these contractions was higher in the S bladder. The intraluminal pressure at full capacity was 31 +/- 15 cm. water for the S bladder and 39 +/- 20 cm. water for the Kock pouch. The similar urodynamic features of the S and Kock pouches indicate their ultimate expansion into reservoirs of close physical characteristics and urodynamic behavior.