Yong Seung Lee

Diagnostic Value of Anteroposterior Diameter of Fetal Renal Pelvis During Second and Third Trimesters in Predicting Postnatal Surgery Among Korean Population: Useful Information for Antenatal Counseling

OBJECTIVEnTo establish prognostic data regarding fetal hydronephrosis using the anteroposterior diameter (APD) and the need for interventional surgery in the Korean population.nnnMETHODSnA total of 187 children with an APD of ≥ 4 mm on obstetric ultrasound scans at any gestational age were retrospectively reviewed. The affected renal units were divided into 2 groups: surgical and nonsurgical. The ultrasound findings were compared at 3 gestational ages: second trimester (15-26 weeks gestation), early third trimester (27-33 weeks gestation), and late third trimester (34-40 weeks gestation).nnnRESULTSnThe area under the receiver operating characteristic curve was 0.770, 0.828, and 0.812 at the second, early third, and late third trimesters, respectively. A 100% sensitivity for predicting postnatal surgery could be achieved at a cutoff APD of 5 mm during the second trimester, 8 mm during the early third trimester, and 10 mm during the late third trimester if scheduled antenatal ultrasound scans were performed. A cutoff APD of 11 mm during the second trimester was of diagnostic value in selecting children at risk of postnatal surgery with an odds ratio of 5.13 (95% confidence interval 1.62-16.25), with relatively high sensitivity and specificity. With a cutoff of 15 mm during the early third and late third trimesters, the odds ratio was 11.51 (95% confidence interval 5.05-26.23) and 6.94 (95% confidence interval 3.30-14.57), respectively.nnnCONCLUSIONnCompared with an APD of 10 mm, the most commonly used standard cutoff value in predicting postnatal hydronephrosis and its outcome, an APD cutoff of 5, 8, and 10 mm during the second, early third, and late third trimesters, respectively, is more specific in predicting the need for postnatal surgical intervention in the Korean population.

Spina bifida occulta: Not to be overlooked in children with nocturnal enuresis

Previous reports have suggested that the incidence of spina bifida occulta in patients with nocturnal enuresis is higher than in the general population. However, the effect of spina bifida occulta on the response to nocturnal enuresis treatment is controversial. The purpose of this study was to investigate the relationship between spina bifida occulta and response to treatment of nocturnal enuresis.

Factors Associated with Complications of the Ureteral Stump After Proximal Ureteroureterostomy

PURPOSEnUreteroureterostomy is a treatment modality for managing an ectopic ureterocele or ectopic ureter and preserving upper pole kidney function. However, the development of urinary tract infection at the residual ureteral stump is a concern. We analyzed factors affecting the development of urinary tract infection at the residual ureteral stump after proximal ureteroureterostomy.nnnMATERIALS AND METHODSnBetween January 2002 and December 2009 proximal ureteroureterostomy was performed in 80 patients with ectopic ureterocele or ectopic ureter associated with a duplex system. Excluding 6 patients who did not meet the study inclusion criteria, we investigated age at operation, diameter of the upper pole ureter on ultrasonography, differential renal function and the presence of vesicoureteral reflux in 74 patients. Risk factors for residual ureteral stump infection and decreased differential renal function were analyzed.nnnRESULTSnDuring a median followup of 5.0 years an additional operation was required in 9 patients (12.2%) due to urinary tract infection at the residual ureteral stump a median of 2.4 years after initial proximal ureteroureterostomy. The preoperative maximal diameter of the upper pole ureter was significantly greater in patients with infection complications. The postoperative maximal diameter of the upper pole ureter was also significantly greater on postoperative ultrasonography performed a median 43.0 days after the operation. Median preoperative and postoperative differential renal function was 47.8% and 47.0%, respectively. No preoperative factors were significantly related to the decrease in differential renal function.nnnCONCLUSIONSnProximal ureteroureterostomy is a safe treatment for ectopic ureterocele or ectopic ureter with a low postoperative complication rate. Upper pole ureter diameter was correlated with the development of a urinary tract infection at the residual ureteral stump.

Preoperative Urodynamic Factors Predicting Outcome of Botulinum Toxin-A Intradetrusor Injection in Children With Neurogenic Detrusor Overactivity

OBJECTIVEnTo investigate urodynamic (UD) parameters that predict outcome of intradetrusor botulinum toxin-A (BTX-A) injection in children with neurogenic detrusor overactivity (NDO), by reviewing clinical and UD data.nnnMETHODSnFrom January 2010 to March 2014, 56 cases of the first BTX-A intradetrusor injection were performed in pediatric patients with NDO. We excluded 19 cases based on these criteria: patient age <4 years, no preoperative UD study or postoperative outcome assessment, and simultaneous sphincter injection. Based on the Patient Global Impression of Improvement, patients were classified as responders or nonresponders.nnnRESULTSnThirty-seven cases were included finally. Mean number of pads used per day was significantly decreased after BTX-A injection (2.67 ± 1.46 vs 1.37 ± 1.15; P <.001). On postoperative UD study, maximum cystometric capacity and residual urine volume were significantly increased above baseline. Persistent NDO was only detected in 3 cases (8.1%). Regardless of UD improvements, 20 cases were responders, whereas 17 were nonresponders based on Patient Global Impression of Improvement. Preoperative bladder compliance was significantly lower in nonresponders (25.11 ± 32.59 vs 8.64 ± 6.52; P = .039). Open bladder neck (OBN) was seen in 9 cases and more likely occurred in nonresponders. Regression analysis revealed that poor bladder compliance (<10 mL/cm H2O; odds ratio, 6.041; 95% confidence interval, 1.189-30.677; P = .030) and presence of OBN (odds ratio, 16.889; 95% confidence interval, 1.825-156.282; P = .031) were independent predictors of poor response after BTX-A injection.nnnCONCLUSIONnPreoperative bladder compliance and OBN were important predictors of outcome after BTX-A intradetrusor injection. Thus, intradetrusor BTX-A injection should be considered in select patients to achieve optimal outcome.

A modified technique for ureteral reimplantation: Intravesical detrusorrhaphy

PURPOSEnTo describe the surgical procedure of intravesical detrusorrhaphy, a modified technique of ureteral reimplantation, and report our initial experience.nnnMETHODSnFrom October 2007 to March 2012, 55 children with vesicoureteral reflux (VUR) and 13 children with obstructive megaureter (OM) underwent intravesical detrusorrhaphy. All surgical procedures were performed via an open intravesical approach. The ureter was mobilized, and the bladder mucosa was separated from the detrusor in a cephalad direction. The separated detrusor was incised vertically and repaired underneath the mobilized ureter to create the submucosal tunnel. The ureteral orifice was anastomosed to its orthotopic position.nnnRESULTSnOf 31 patients treated with bilateral intravesical detrusorrhaphy, no patient had postoperative urinary retention. Follow-up voiding cystourethrography was performed in 45 patients with 72 reimplanted ureters. VUR was resolved in 41 patients (91.1%) with 68 ureters (94.4%). Among 13 patients with 14 ureters treated for OM, hydroureteronephorosis improved in 11 patients (84.6%) with 12 ureters (85.7%).nnnCONCLUSIONSnIntravesical detrusorrhaphy is modified technique of ureteral reimplantation, which recreates the neo-ureteric orifice in the orthotopic position and does not produce postoperative urinary retention in bilateral cases. Intravesical detrusorrhaphy is safe and effective in treating patients with VUR or OM.

Prerequisite for Successful Surgical Outcome in Urothelium Lined Seromuscular Colocystoplasty

PURPOSEnUrothelium lined seromuscular colocystoplasty is an ideal method of augmentation cystoplasty that avoids various complications caused by the use of gastrointestinal segments. We reviewed the long-term outcomes using this technique at a single institution.nnnMATERIALS AND METHODSnWe retrospectively analyzed 34 patients who underwent urothelium lined seromuscular colocystoplasty between January 1996 and December 2007. A total of 33 patients, excluding 1 who had previously undergone artificial urinary sphincter implantation, were included in the study. Changes in urodynamic parameters, duration of anticholinergic use, incontinence and surgical complications were analyzed.nnnRESULTSnMean±SD age at surgery was 10.0±5.7 years (range 3.0 to 26.0) and duration of followup was 6.0±2.3 years (2.7 to 13.4). A total of 17 patients (51.5%) underwent simultaneous anti-incontinence surgery and urothelium lined seromuscular colocystoplasty. Mean bladder capacity increased by a factor of 2.96 and mean percentage of expected bladder capacity for age increased by a factor of 1.96 postoperatively. Of patients who underwent anti-incontinence surgery 4 of 10 whose abdominal leak point pressure was less than 40 cm H2O required additional surgery, whereas none whose abdominal leak point pressure was 40 to 60 cm H2O required reoperation. Two of 16 patients who did not undergo anti-incontinence surgery eventually required continence surgery. A total of 13 patients (39.4%) were able to discontinue anticholinergics at 47.3 months postoperatively. There were no bladder perforations, bowel obstructions or metabolic abnormalities.nnnCONCLUSIONSnUrothelium lined seromuscular colocystoplasty can be primarily considered in patients without prior bladder mucosal injury. Constant high bladder outlet pressure to facilitate adhesion of bladder mucosa and seromuscular patch is critical for the best results. We recommend abdominal leak point pressure 60 cm H2O or less as an indication for simultaneous anti-incontinence surgery and urothelium lined seromuscular colocystoplasty.

Impact of ectopic insertion on treatment outcome of primary non-refluxing megaureter.

OBJECTIVEnTo investigate the characteristics of primary non-refluxing megaureter with ectopic insertion and its effects on renal function.nnnMETHODSnOf 118 patients diagnosed with primary non-refluxing megaureter, we retrospectively studied 33 patients who underwent surgical treatment. Depending on the position of ureteral insertion, patients were classified as having either an ectopic or orthotopic megaureter; clinical characteristics and renal function, were analyzed.nnnRESULTSnAmong the 36 primary non-refluxing megaureters, 7 (19.4%) had ectopic megaureter. A total of 34.5% of the orthotopic megaureter and all ectopic megaureter cases were women (P = .003). The mean value of maximum ureteral diameter was significantly wider for ectopic than for orthotopic megaureter (16.3 vs 12.1 mm, respectively, P = .029). Mean preoperative differential renal function (DRF) were 36.4% and 43.0% for ectopic and orthotopic megaureters, respectively (P = .164). After surgery, the mean DRF of ectopic megaureter had decreased from 50% to 18.8%, whereas the mean DRF of orthotopic megaureter was 42.9% (P <.001). At the time of surgery, the mean age of patients was 4.6 months in the ectopic megaureter and 16.7 months in the orthotopic megaureter (P = .005).nnnCONCLUSIONnIn our study, all the cases of an ectopic megaureter occurred in women, and the ureteral dilatation was comparatively more severe than in orthotopic megaureters. In addition, despite early surgical treatment, renal function deteriorated gradually. Further analyses are necessary to determine whether earlier surgical intervention for preventing deterioration of renal function is worthwhile or not.

Factors Indicating Renal Injury in Pediatric Bilateral Ureteropelvic-junction Obstruction

OBJECTIVEnTo analyze the factors indicating renal injury in patients with bilateral ureteropelvic-junction obstruction (UPJO).nnnMETHODSnWe investigated 26 patients, 35 kidney units (KUs), who were diagnosed with bilateral UPJO and underwent unilateral or bilateral pyeloplasty between January 2000 and December 2011. During pyeloplasty, ipsilateral kidney biopsy was performed. Kidney biopsy results were divided into 3 categories. Hydronephrosis was analyzed using both the Society of Fetal Urology (SFU) and Onens grading system. We investigated factors related with the renal histopathologic results of 29 KUs. We additionally analyzed whether there were factors predicting contralateral pyeloplasty after initial unilateral pyeloplasty.nnnRESULTSnTen KUs (34.5%) showed grade 1 histopathologic change, whereas 10 KUs (34.5%) and 9 KUs (31.0%) showed grade 2 and 3 change, respectively. Preoperative differential renal function (DRF) and serum creatinine levels were not different among groups (Pxa0= .697 and .516, respectively). Hydronephrosis grade was not different when graded by SFU system (Pxa0= .100) while significantly different by Onens system (Pxa0<.001). Among 23 patients with initial unilateral pyeloplasty, additional contralateral pyeloplasty was required in 6 patients (26.1%). There were no significant preoperative factors predicting the need for additional operations.nnnCONCLUSIONnIn bilateral UPJO, DRF, and SFU grade of hydronephrosis did not correctly reflect renal injury. Onens hydronephrosis grade showed a significant relationship with renal histopathologic grade and could be an indicator for renal injury in bilateral UPJO.

The significance of detrusor wall thickness as a prognostic factor in pediatric bladder outlet obstruction

PURPOSEnThe purpose of this study is to determine detrusor thickness as a prognostic factor in posterior urethral valves.nnnMETHODSnThe medical information of 41 patients diagnosed with posterior urethral valves at our institute was retrospectively reviewed. The serum creatinine level after bladder decompression, results of ultrasonography, and voiding cystourethrography were compared between groups divided according to the final bladder and renal function. Detrusor thickness was measured using Müllers method.nnnRESULTSnThe median detrusor thickness was 1.3 mm (0.4-2.5 mm). After median 45.6 months (7.2-96.0 months) of follow-up, impaired bladder function (IBF) was observed in 14 patients. In multivariate analysis, detrusor thickness greater than 1.3 mm (odds ratio, 32.6; 95% confidence interval, 3.1-340.6; P = .004) was the only independent risk factor for later IBF. Final renal function impairment developed in 24 patients (58.5%), and 3 patients (7.3%) were diagnosed with end-stage renal disease after median 66.0 months (32.4-133.2 months) of follow-up period. On multivariate analysis, age-specific elevated serum creatinine level at presentation (odds ratio, 11.1; 95% confidence interval, 1.1-112.5; P = .042) was an independent risk factor.nnnCONCLUSIONSnDetrusor thickness more than 1.3 mm on ultrasonography was an independent prognostic factor for later IBF.

Does Hydronephrosis After Extravesical Ureteral Reimplantation Deteriorate Renal Function

PURPOSEnWe analyzed whether newly developed or aggravated hydronephrosis deteriorates differential renal function after extravesical ureteral reimplantation.nnnMATERIALS AND METHODSnWe performed extravesical ureteral reimplantation in 93 patients with unilateral vesicoureteral reflux between January 2006 and December 2009. Excluding 3 patients with other combined disease, a retrospective cohort analysis of 90 consecutive patients was conducted. We performed ultrasonography before and 1 month after extravesical ureteral reimplantation, and dimercapto-succinic acid scan before and 6 months after extravesical ureteral reimplantation. Of the patients 83 underwent final dimercapto-succinic acid scan at 6 months postoperatively. We analyzed the preoperative studies and perioperative parameters to evaluate the factors affecting newly developed or aggravated hydronephrosis at 1 month, and decrease in differential renal function at 6 months after extravesical ureteral reimplantation.nnnRESULTSnNewly developed or aggravated hydronephrosis was observed in 25 patients (28.4%) 1 month after extravesical ureteral reimplantation. Younger age at surgery was a risk factor (p = 0.003). Of the patients 23 showed improvement on ultrasound 6 months postoperatively. In 12 patients (15.7%) a decrease in differential renal function of more than 5% was observed 6 months postoperatively. Preoperative parenchymal reduction on dimercapto-succinic acid scan was the only significant factor (p = 0.008). There was no correlation between newly developed or aggravated hydronephrosis and final decrease in differential renal function (p >0.999).nnnCONCLUSIONSnAlthough newly developed or aggravated hydronephrosis after extravesical ureteral reimplantation is common, especially in younger patients, it is transient and does not affect differential renal function. A postoperative decrease in differential renal function without further urinary tract infection could develop when there is a parenchymal reduction on preoperative dimercapto-succinic acid scan.