Effects of Mirodenafil, a Phosphodiesterase-5 Inhibitor, on Female Rat Bladder in a Partial Bladder Outlet Obstruction Model: Physiological and Immunohistochemical Aspects

PURPOSE: We investigated the effects of mirodenafil, a phosphodiesterase-5 inhibitor developed in South Korea, on the female rat bladder in a partial bladder outlet obstruction (BOO) model. MATERIALS AND METHODS: Thirty-six female Sprague-Dawley rats were divided into four groups: the control group, BOO without medication group, BOO with mirodenafil 1 mg/kg group, and BOO with mirodenafil 4 mg/kg group. Mirodenafil was administered orally for 2 weeks after the induction of BOO. Two weeks after BOO, the rats in each group underwent cystometry under urethane anesthesia. After cystometry, the bladder was excised to perform immunohistochemical staining for connexin 43. RESULTS: The three BOO groups showed significant increases in mean bladder weight compared with the control group. Baseline pressure, threshold pressure, and maximum contraction pressure were not significantly different between the four groups. Although the contraction interval was decreased in all BOO groups compared with the control group, it was prolonged in the two groups treated with mirodenafil compared with the untreated BOO group. In the immunohistochemical examination, connexin 43 staining intensity in the lamina propria increased in the three BOO groups compared with the control group. The two groups treated with mirodenafil, however, showed decreased connexin 43 staining compared with the untreated BOO group. CONCLUSIONS: Mirodenafil may increase the contraction intervals of female rat bladders in a partial BOO model. Decreasing bladder overactivity by mirodenafil may be related to intracellular communication mechanisms involving connexin 43.

Analysis of Octyl-2-Cyanoacrylate as a Dressing Material after Pediatric Urological Procedures

PURPOSE: We aimed to evaluate the efficacy of Octyl-2-cyanoacrylate (Dermabond(TM)) as a topical skin adhesive for pediatric urologic open surgery. METHODS: From August 2010 to August 2011, we retrospectively evaluated pediatric patients who underwent urologic open surgery at our institution. A total of 128 pediatric patients with 210 incisions used Dermabond(TM) for skin closure. RESULTS: We divided the 128 patients into 3 groups according to type of surgery. Group 1 underwent hydrocelectomy (55 cases, 41.3%), Group 2 underwent orchiopexy (43 cases, 32.3%), Group 3 underwent penoplasty (35 cases, 26.4%). One hundred and twenty eight patients who underwent 133 surgeries in total, with a total of 210 incisions visited our outpatient department postoperatively, and a total of 5 wound complications (2.3%) occurred, but were simple inflammations and no dehiscence was observed. When analyzed according to groups, no wound problems occurred in Group 1 (0/55, 0%), one occurred in Group 2 (1/43, 2.3%) and four cases occurred in Group 3 (4/35, 11.4%) respectively. When re-analyzed according to wound locations, one occurred in an inguinal wound (1/120, 0.83%), none occurred in scrotal wounds (0/55, 0%), and four occurred in penile wounds (4/35, 11.4%). In Group 3, the incidence of penile wounds was significantly increased compared to other groups (P=0.008). All 5 wound problems were inflammatory and healed at an average of 13.8 days (13-15 days) with antibiotic ointment application only. CONCLUSION: Dermabond(TM) is feasible and safe topical skin adhesive alternative to standard skin suture in pediatric urologic surgery. However, further research about its efficacy and safety could be valuable in the future.

Impact of Cardio-Pulmonary and Intraoperative Factors on Occurrence of Cerebral Infarction After Early Surgical Repair of the Ruptured Cerebral Aneurysms

OBJECTIVE: Delayed ischemic deficit or cerebral infarction is the leading cause of morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH). The purpose of this study is to reassess the prognostic impact of intraoperative elements, including factors related to surgery and anesthesia, on the development of cerebral infarction in patients with ruptured cerebral aneurysms. METHODS: Variables related to surgery and anesthesia as well as predetermined factors were all evaluated via a retrospective study on 398 consecutive patients who underwent early microsurgery for ruptured cerebral aneurysms in the last 7 years. Patients were dichotomized as following; good clinical grade (Hunt-Hess grade I to III) and poor clinical grade (IV and V). The end-point events were cerebral infarctions and the clinical outcomes were measured at postoperative 6 months. RESULTS: The occurrence of cerebral infarction was eminent when there was an intraoperative rupture, prolonged temporary clipping and retraction time, intraoperative hypotension, or decreased O2 saturation, but there was no statistical significance between the two different clinical groups. Besides the Fisher Grade, multiple logistic regression analyses showed that temporary clipping time, hypotension, and low O2 saturation had odds ratios of 1.574, 3.016, and 1.528, respectively. Cerebral infarction and outcome had a meaningful correlation (gamma=0.147, p=0.038). CONCLUSION: This study results indicate that early surgery for poor grade SAH patients carries a significant risk of ongoing ischemic complication due to the brain's vulnerability or accompanying cardio-pulmonary dysfunction. Thus, these patients should be approached very cautiously to overcome any anticipated intraoperative threat by concerted efforts with neuro-anesthesiologist in point to point manner.

Experiences of Renal Transplantation after Correction of Dysfunctional Contracted Bladder / 대한이식학회지

BACKGROUND: There is some controversy about the safety of renal transplantation in patients with an augmentation cystoplasty. The purpose of this study is to assess the early and long-term results of renal transplantation in 6 patients who underwent augmentation cystoplasty to correct bladder dysfunction. METHODS: We retrospectively reviewed the surgical outcome of renal transplants in 6 recipients with augmentation cystoplasty including one ileal conduit. The etiology of bladder dysfunction was neurogenic bladder with detrusor hyperreflexia (4 pediatric patients) and renal tuberculosis (2 adult patients). Augmentation cystoplasty was performed before transplantation in all patients. The bowel segments used in the augmentation cystoplasty included stomach in 2 (including one revision case with ileum), ileum in 3, ileocecal segments in 1, and sigmoid colon in 1 patients. The mean patient's age at transplantation was 25.5 years. Four transplants were from living donors. The donor ureter was anastomosed to ileal conduit in 1, native bladder in 2, and the bowel segment in 3 patients. RESULTS: All transplanted kidneys were functioning at a mean follow-up of 103 months (range 5 to 220). The mean serum creatinine level was 1.0 mg/dl (range 0.7 to 1.8). Acute rejection was diagnosed in protocol biopsy in one patient without graft function deterioration. Four patients admitted for febrile urinary infection during the follow up periods. CONCLUSIONS: Augmentation cystoplasty is a safe and effective method to restore the renal function in patients who have noncompliant bladders. Renal transplantation can be performed safely after augmentation cystoplasty.

Efficacy and Tolerability of Extended-release Oxybutynin in Children with a Neurogenic Bladder / 대한비뇨기과학회지

PURPOSE: The aim of this study was to investigate the efficacy and tolerability of extended-release oxybutynin(oxybutynin ER) in children with a neurogenic bladder. MATERIALS AND METHODS: Fifty-four patients(21 myelomeningocele and 33 lipomyelomeningocele) with a neurogenic bladder were enrolled in the study. We reviewed the medical records and performed a telephone interview. The treatments were changed from immediate-release oxybutynin (oxybutynin IR) or other anticholinergics to oxybutynin ER from August to December 2006. The mean age of the study patients was 11.1 years (range 4 to 18 years) and the mean body weight was 37.9kg(range 16.2 to 72.0kg). All patients were asked about the effectiveness, side effects and compliance with the medication. The number of voids, volume of urine per void or clean intermittent catheterization(CIC) and number of incontinence episodes were also evaluated. RESULTS: The mean duration of oxybutynin ER treatment was 16.3 weeks (range 7-25 weeks). Twenty-six patients(48.1%) responded they had improvement in voiding symptoms. Among the patients, there was a significant reduction in the number of incontinence episodes(from 3.3 to 1.3, p<0.001) with the change in medications. The number of voids or CIC per 24 hours and the maximum volume of urine per void or CIC did not show a significant change. Another twenty-eight patients(51.9%) responded that the improvements were maintained. Among these patients, there were no significant changes of the medications. Only five patients (9.3%) changed their medication because of the side effects. CONCLUSIONS: The results of this study showed that the extended-release oxybutynin was effective and well tolerated in children with a neurogenic bladder.

Dextranomer/Hyaluronic Acid Copolymer (Deflux(R)) Injection for Vesicoureteral Reflux in Children: the Efficacy and Safety / 대한비뇨기과학회지

PURPOSE: We evaluated the efficacy and safety of Deflux injection for treating vesicoureteral reflux (VUR) in children. MATERIALS AND METHODS: Between January 2004 and May 2006, 49 children (28 boys and 21 girls) with a mean age of 51 months (5-182) underwent Deflux injection. VUR was unilateral in 19 cases (38.8%) and bilateral in 30 (61.2%), affecting 79 ureters. VUR was grades II to V in 26 cases (32.9%), 24 (30.4%), 16 (20.3%), and 4 (5.1%), respectively. Our clinical protocol involved ultrasonography at 6 weeks to evaluate the development of hydronephrosis and the creation of submucosal mound, and VCUG or RIVCU at 3 months to assess the VUR. RESULTS: The median follow-up was 8.0 months (1-22). The cure rate at 3 months by the ureter was 81.6% (88.9% for grade I, 100% for grade II, 79.2% for grade III, 75.0% for grade IV, and 50.0% for grade V) and the cure rate was 84.8% for the total patients (100% for the unilateral cases and 80% for the bilateral cases). There were 16 patients with 1 year of follow-up and the cure rate was 88.5% by the ureter and 87.5% for the total patient. The severity of VUR (p=0.035) and the concomitant voiding dysfunction (p=0.001) were the significant predictors of a successful outcome. One patient complained of gross hematuria resolved within a few days. CONCLUSIONS: Deflux injection was safe and efficacious with a low complication rate. The severity of VUR and the concomitant voiding dysfunction had significant adverse effects on the cure rate.

Extravasation from the Distal Anterior Choroidal Artery Aneurysm in Moyamoya Patient during Computed Tomographic Angiography

Three-dimensional computed tomographic angiography (CTA), a representative noninvasive radiologic technique, is being widely used for detecting vascular lesions in specific intracranial bleeding under a certain circumstance (acute nontraumatic subarachnoid hemorrhage). We encountered a case of extravasation of the contrast medium on CTA images that appeared as ribbon-like high-attenuation lesion from an aneurysm at the distal anterior choroidal artery in a young adult moyamoya patient. As CTA is used more frequently, it is imperative to understand such unusual but, potentially lethal image findings to conduct a prompt intervention.

Aneurysmal Subarachnoid Hemorrhage Associated with Achondroplasia: Case Report / 대한뇌혈관외과학회지

Patients with achondroplasia manifest various neurologic symptoms including megaencephaly, hydrocephalus, and progressive myelopathy or radiculopathy secondary to spinal stenosis. However, only anecdotal postmortem reports proved ruptured aneurysm or vascular malformation as a source of intracranial hemorrhage. We herein report a case of a 26-year-old woman with achondroplasia who underwent uneventful surgical treatment for the aneurysmal subarachnoid hemorrhage. In this literature, we review the pathophysiologic mechanism and emphasize the necessity of considering the possibility of sudden mental deterioration in achondroplastic patient.

Influence of Lamina Terminalis Fenestration on the Occurrence of the Shunt-Dependent Hydrocephalus in Anterior Communicating Artery Aneurysmal Subarachnoid Hemorrhage

Recently, it was reported that fenestration of the lamina terminalis (LT) may reduce the incidence of shunt-dependent hydrocephalus in aneurysmal subarachnoid hemorrhage (SAH). The authors investigated the efficacy of the LT opening on the incidence of shunt-dependent hydrocephalus in the ruptured anterior communicating artery (ACoA) aneurysms. The data of 71-ruptured ACoA aneurysm patients who underwent aneurysmal clipping in acute stage were reviewed retrospectively. Group I (n=36) included the patients with microsurgical fenestration of LT during surgery, Group II (n=35) consisted of patients in whom fenestration of LT was not feasible. The rate of shunt-dependent hydrocephalus was compared between two groups by logistic regression to control for confounding factors. Ventriculo-peritoneal shunts were performed after aneurysmal obliteration in 18 patients (25.4%). The conversion rates from acute hydrocephalus on admission to chronic hydrocephalus in each group were 29.6% (Group I) and 58.8% (Group II), respectively. However, there was no significant correlation between the microsurgical fenestration and the rate of occurrence of shunt-dependent hydrocephalus (p>0.05). Surgeons should carefully decide the concomitant use of LT fenestration during surgery for the ruptured ACoA aneurysms because of the microsurgical fenestration of LT can play a negative role in reducing the incidence of chronic hydrocephalus.

Efficacy and Tolerability of Tolterodine Compared to Oxybutynin in Children with a Neurogenic Bladder / 대한비뇨기과학회지

PURPOSE: The aim of this study was to investigate the efficacy and adverse effects of oral tolterodine compared to oxybutynin in children with a neurogenic bladder. MATERIALS AND METHODS: 16 patients, with persistent daytime or nighttime wetting after oxybutynin medication for the treatment of a neurogenic bladder, were enrolled. All 16 patients had been crossed-over from oxybutynin to tolterodine due to serious side effects or lack of improvement. The mean age was 6.4 years (range 3 to 11), and the mean body weight was 22kg (range 16 to 33). All patients were initially treated with oral tolterodine, 2mg, twice daily. The efficacy of tolterodine was assessed in comparison to oxybutynin, and considered as improved with a greater than 50% reduction in wetting episodes, as stationary with a less than 50% reduction or as increased or aggravated with a greater than 50% increase. The tolerability was also assessed using a questionnaire for adverse events. RESULTS: The mean duration of tolterodine treatment was 193 days (range 14 to 940). After treatment with an initial tolterodine dose of 2mg bid, 5 patients (31%) were improved, 8 (50%) were stationary and 3 (19%) were aggravated. Overall, the initial tolterodine dose showed equal efficacy to that of oxybutynin (p=0.483). Of the 16 patients, side effects developed in 12 (75%) during the oxybutynin treatment, whereas only 2 (13%) developed side effects during the tolterodine treatment (p=0.001). CONCLUSIONS: Compared to oxybutynin, tolterodine was well tolerated in children, allowing greater compliance and offering an equally effective treatment for neurogenic incontinence in children with a neurogenic bladder. Therefore, it seems that tolterodine can be safely and effectively used to replace oxybutynin in children with a neurogenic bladder.

Cerebral Aneurysm and Aortic Coarctation in a 46, XY Female. Is it Causal or Coincidental?

Most vascular disorders tend to affect both the brain and heart, and among them, a clinical syndrome constituting cerebral aneurysm and aortic coarctation(AC) has been well recognized. Persistent hypertensive impact to the cerebral vasculature with developmental anomaly of the neural crest, precursor of ectomenchymal, would be closely associated with development of the cerebral aneurysm in AC. Gonadal steroid hormone, a guardian of the cardiovascular system, has been known for its protective effects on the vascular wall. Gonadal steroid hormone (androgen) insensitivity such as 46, XY female syndrome may increase the risk of hypertention and subsequent vascular anomalies. The authors report on a 46-year-old 46, XY female patient with AC who underwent surgical clipping of the ruptured cerebral aneurysm. Clinical implications and proposed pathogenetic mechanisms of aneurysm in this intersex syndrome are presented and discussed.

alpha-Adrenoceptor Antagonistic Effect of Palmatine on the Prostatic Urethral Pressure of the Rabbit / 대한비뇨기과학회지

PURPOSE: Palmatine is an isoquinoline alkaloid, with multiple pharmacological actions, including anti-inflammatory activity. The aim of this study was to examine the effect of palmatine on the prostatic urethral pressure in anesthetized rabbit. MATERIALS AND METHODS: 10-week-old male New Zealand White rabbits (3.0-3.5kg) were used in the experiment. After anesthetized with urethane (800mg/kg i.v.), a midline incision was made, and the urinary bladder completely drained. To prevent filling of the bladder, polyethylene tubes were inserted into the bilateral ureters. Using a 3-F MIKRO-TIP catheter transducer positioned in the prostatic urethra, urethral pressure was recorded continuously. To record the blood pressure, the left femoral artery was cannulated with an angiocatheter. After a stabilizing period, phenylephrine (1mug/kg) was intravenously administered two or three times. When the increase in the urethral pressure became stable, palmatine was administered intravenously (0.5-3.0mg/kg), followed by phenylephrine, with no time interval. RESULTS: In the anesthetized rabbits, an intravenous bolus injection of palmatine (0.5-3.0mg/kg) caused no significant change in the resting prostatic urethral pressure (p>0.05), but decreased the blood pressure (p<0.05). After administration of phenylephrine, the urethral pressure increased from 7.5 0.8 mmHg to 26.5 2.6 mmHg, with the difference in the pressure (19.0 3.1 mmHg) being statistically significant (p<0.01). The intravenously administered palmatine (0.5-3.0mg/kg) dose-dependently inhibited the phenylephrine-induced increases in the prostatic urethral pressure and mean blood pressure. The maximal inhibition was obtained when a palmatine dose of 3.0mg/kg was administered, at which point, the decrease in the urethral pressure was 73.1% (p<0.01). CONCLUSIONS: These results indicate that palmatine inhibits the phenylephrine-induced increases in the prostatic urethral pressure and blood pressure in the anesthetized rabbits.

Bladder Dysfunction in Focal Cerebral Ischemia of Rat / 대한비뇨기과학회지

Purpose: The purpose of this study was to evaluate the active contractile properties of detrusor smooth muscle from bladders of cerebral-infarcted rats (CI rats). Materials and Methods: The cerebral infarction was induced in 8 to 9 week-old male Sprague-Dawley rats by occlusion of the left middle cerebral artery. At 2 and 4 weeks after the operation, bladder muscle strips were evaluated for force development in response to electrical field, 5 micrometer carbachol (Cch) and 60mM KCl stimulation using an isometric transducer. The contractile response to field stimulation on the additions of 1micrometer atropine and 5micrometer alpha, beta-methylene ATP (abmATP) were measured, and the contributions of cholinergic and purinergic transmissions determined. Cystometrography (CMG) was also performed in anaesthetized rats. Results: In comparison with sham-operated rats, the CI rats showed a shorter voiding interval, smaller peak voiding pressure, smaller voiding volume and greater residual urine volume on CMG. The CI rats also showed smaller tension at maximum contraction induced by Cch and a quicker response to maximum contraction induced by KCl than the sham operated rats. The CI rats showed time-dependent increases and decreases in the proportions of abmATP-sensitive (purinergic) and atropine-sensitive (cholinergic) components, respectively. Conclusions: CI rats showed changes in detrusor activity, contractility and the proportions of cholinergic and purinergic components. The increase in the purinergic contraction of the detrusor muscle was believed to be related to bladder instability. The results of this study will be useful in explaining detrusor hyperactivity, with impaired contractility (DHIC), in patients with cerebral infarction.

Anterior Interbody Fusion for Cervical Fracture-Dislocations

Cervical fracture-dislocation continue to be a difficult therapeutic problem. It gives more prolonged and complexing neurological deficits and complications than any other injuries. Since the introduction of skull tongs for skeletal traction by Crutchfield in 1933, very little had been added to treat cases until the works of Dereymaeker, Smith and Robinson, and Cloward who introduced the value of anterior approach for cervical fracture-dislocations around 1955. The author reviewed 51 cases of cervical fracture-dislocation treated at Severance Hospital and Hanyang University Hospital from 1964 to 1972; 23 cases were treated by simple traction, 27 cases by anterior interbody fusion, and one cases by posterior internal splint using resin and wiring. 1. Early anterior approach offers a unique opportunity to treat the lesion under direct vision. The spinal instability can be corrected by a vertebral fusion, and prolonged immobilization in skull traction may be avoided. 2. Myelography and Queckenstedt's test is not indicated except in the few limited cases to find ruptured disc lesions. 3. Acute ruptured disc was found in almost all the surgical cases. In many cases, disc removal was imperative after conservative therapy. And interbody fusion gives the best prognosis. 4. For the reduction of new locked facets, posterior approach is easier and safer than anterior approach. But in the case of old locked facets, all scar tissue should be excised via anterior approach before performing posterior approach. 5. Postoperative anterior angulation of cervical spine resulted from compression of vertebral body at the time of injury, and it may be prevented by hyperextended surgical position of the cervical spine during interbody fusion and postoperative fraction for two to three weeks.

Acute Cervical Subdural Hematoma Following Minor Trauma, with Complete Recovery

A case is reported in which spinal cord compression was caused by acute subdural hematoma following minor injury of the cervical spine in an 8 year old girl, with recovery following early surgical evacuation.

Drug therapy in chilhood enuresis / 대한비뇨기과학회지

We evaluated the results of drug therapy in 76 children with nocturnal enuresis, who were free of other abnormalities in screening tests. History taking, careful physical examination including back area. urinalysis, urine culture, KUB and uroflowmetry were the screening tests. Overall response rate was 69.7 %. We found no statistically significant differences in responses between primary and secondary enuresis to drug therapy. We also found no difference in response according to the drugs including imipramine hydrochloride alone, oxybutynin chloride alone and combining of both. There was no difference in the results of the presence or the absence of daytime frequency and urgency. Two patients who resisted to the long-term therapy of imipramine hydrochloride and oxybutynin chloride showed good responses to the administration of intra-nasal desmopressin acetate. These data suggest that oxybutynin chloride does not show better therapeutic results than imipramine hydrochloride, whereas desmopressin acetate may be used for intractable enuresis to conventional drug therapy.

Effect of Ginseng Extract on Blood Pressure and Intracranial Pressure in Cats

There are two contradictive opinions of the therapeutic administration of Ginseng in the conditions of cerebrovascular accident and/or hypertensive heart diseases. This experimental study was performed to observe the effects of the Ginseng extract on the blood pressure(BP) and intracranial pressure(ICP) at the same time. Seven mongrel cats were used. ICP was measured with epidural ballon and pressure transducer, and BP with intraarterial catheter via female routs. Both were continuously recorded by polygrapher. 1. In a normal condition, a single intravenous injection of Ginseng 100mg/kg induced immediate reduction of BP for 30~45 second. Intracranial pressure, however, showed delayed elevation for 50~60 second. 2. Even in a condition of increased ICP or induced cardiac hypertension, the results were the same as in above-described normal condition.

Effects of Combined Drug Therapy in the Nocturnal Enuretic Patients / 대한비뇨기과학회지

PURPOSE: Recently there have been arguments about the exact nature of pathophysiology of nocturnal enuresis. Desmopressin and imipramine have been used for drug therapy. Also oxybutynin chloride has been used to treat the children having nocturnal enuresis and diurnal voiding symptoms. Practically most nocturnal enuretic patients who visit outpatient clinic really want to quit their enuretic episode quickly and durably without side effect of drug therapy. We evaluated the effectiveness of combined drug therapy in the primary nocturnal enuretic patients who had 7 times episodes in a week. MATERIALS AND METHODS: In a total of 36 nocturnal enuretic patients(male:female=24:12) whose ages ranged from 4- to 12-year-old(mean; 7.9-year-old), we initially used two or three drugs among oxybutynin chloride(O) t.i.d., imipramine(I) h.s. and desmopressin(D) h.5. for the 24 patients who have urgency and/or daytime enuresis(DE): O+l for 8 patients, O+D for 4,1+D for 4 and 0+1+D for 8. For 12 monosymptomatic enuretic(ME) patients without having diurnal symptoms,0 h.s.+1 h.s.(in 5 patients) or 1 h.s.+D h.s.(in 7 patients) were used. Usual doses in a time are as follows: 2.5mg p.o. for 0,25mg p.o. for 1,20mg intranasally for D or 0.2mg p.o. for 8. RESULTS: At the first follow-up visit(2 weeks later), 14 patients had up to 3 enuretic episodes in a 2 weeks period(judged as success) in the 24 DE patients. Among the successful patients, 2 used O+l, 2 used O+D, 4 used 1+D and 6 used 0+1+D at the start. In the 12 ME patients,5 had success. Four of the 5 successful patients had used 1+D. At the second visit(6 weeks later from the beginning), 16 patients who had not showed success at the first follow-up visit were analysed. Ten(6 DE and 4 ME) of the 16 patients became success. Five DE and 3 ME patients among the 10 successful patients had newly used D or increased D dose during the second period. Three patients (1+D in 1 DE,0+1+D in 1 DE and 1+D in 1 ME)who had showed success at 2 week visit became worse at 6-week visit after dose reduction in 1(12.5mg). CONCLUSIONS: From the above data, we think that combined use of imipramine and desmopressin is effective for initial treatment in the enuretic patients regardless of diurnal symptom. To improve success rate, desmopressin dose needs to be increased.

Nocturnal Enuresis / 소아과

No abstract available.

Hypospadias Repair: Current Experience Using Operating Microscope / 대한비뇨기과학회지

Currently improving results of hypospadias repair depend on careful application of surgical principles. Optical magnification. microsurgical instruments, fine suture materials, less reactive tubes and bio-occlusive dressings have been used to decrease postoperative complications requiring secondary surgery. We evaluated the effectiveness of microscopic surgery which was performed in 28 children with hypospadias from December, 1991 to June, 1994. Nine patients underwent hypospadias repair before 2 years-old whereas 19 patients after 2 years-old, whose success rate was 78% and 63% respectively. One-stage repair was performed in 19 patients and two-stage repairs in 9 patients, whose success rate was 69% and 67% each other. In chronological review, success rate was 50%, 29%, 77% and 100% in 1991, 1992, 1993 and 1994 respectively, which showed a rapidly increasing success rate. According to dressings and catheters, excellent results were obtained when we used Duodenum dressings and silastic Foley catheters, of which each complication rate was 7% and 0% respectively. In 9 patients(32 %), we experienced 20 surgical complications which included urethrocutaneous fistula (9), meatal stenosis(4) stricture(2) and others(5). The success rate of fistula repair was 61% in initial, 40% in secondary and 33% in tertiary repair. From these data, we think that the use of operating microscope with microsurgical principles and proper postoperative managements can improve success rate of hypospadias repair.