1095Vol. 10 | No. 4 | Autumn 2013 |U R O LO G Y J O U R N A L The Effect of Urethral Catheter Size on Meatal Stenosis Formation in Children Undergoing Tubularized Incised Plate Urethroplasty Suleyman Cuneyt Karakus,1 Naim Koku,1 Mehmet Ergun Parmaksiz,1 Idris Ertaskin,1 Huseyin Kilincaslan,2 Hasan Deliaga,3 Corresponding author: Huseyin Kilincaslan, MD Department of Pediatric Surgery, Faculty of Medicine, Adnan Menderes Bulvari, Bezmialem Vakif University, 34093 Fatih, İstanbul, Turkey Tel: +90 505 939 7834 Fax: +90 212 534 6970 E-mail: hkilincaslan@yahoo.com.tr Received October 2012 Accepted March 2013 1 Department of Pediatric Surgery, Gaziantep Children Hospital, Gazi- antep, Turkey 2 Department of Pediatric Surgery, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey 3 Department of Pediatric Surgery, Servergazi State Hospital, Denizli, Turkey PEDIATRIC UROLOGY Purpose: Meatal stenosis is still a common problem in tubularized incised plate urethro- plasty. In this study, we aimed to seek for a relationship between the size of urethral catheter and meatal stenosis formation in children undergoing tubularized incised plate urethroplasty. Materials and Methods: We retrospectively reviewed 83 children who underwent tubular- ized incised plate urethroplasty for hypospadias. The whole group was classified into the groups A and B based on the catheter size. One group (group A) consisted of 44 patients (mean age, 4.82 ± 3.83 years) with tubularized neourethra over a 6 Fr catheter, while the other group (group B) included 39 patients (mean age, 5.19 ± 3.83 years) with tubularized neourethra over a 8 Fr catheter. Results: There were no significant differences between the groups according to their age, lo- cation of urethral meatus, dehiscence and urethrocutaneous fistula formation. Meatal stenosis formation in group B was markedly higher than that in group A. Number of meatal dilatation was higher in group B compared to group A. Conclusion: We suggest that the tubularization of urethral plate over a small-sized (6 Fr) catheter, regardless of the age of the patients, prevents meatal stenosis by reducing foreign body reaction and pressure injury and by hindering secondary healing. Keywords: hypospadias; child; urethra; treatment outcome; urologic surgical procedures; urethral stricture. 1096 | INTRODUCTION Tubularized incised plate (TIP) urethroplasty has become the most commonly used method in pa-tients with distal and mid-shaft hypospadias in re- cent years. Although there have been modified techniques described in order to reduce meatal stenosis, it is still a com- mon problem in TIP urethroplasty.(1-3) However, the size of the urethral catheter may be a factor to prevent meatal ste- nosis. To the best of our knowledge, it is the first reported study that seeks for a relationship between the size of ure- thral catheter and meatal stenosis formation in children un- dergoing TIP urethroplasty. MATERIAL AND METHODS We retrospectively reviewed 83 children who underwent TIP urethroplasty for hypospadias performed by the first author between May 2008 and March 2011 at Gaziantep Children Hospital, Turkey. The whole group was classified into the groups A and B based on the catheter size. One group (group A) consisted of 44 patients (mean age, 4.82 ± 3.83 years, range 1-16 years) with tubularized neourethra over a 6 French (Fr) catheter, while the other group (group B) included 39 patients (mean age, 5.19 ± 3.83 years, range 1-13 years) with tubularized neourethra over a 8 Fr catheter. Glanular hypospadias and secondary repair were excluded from this study. Under general anesthesia, formal TIP urethroplasty opera- tion was performed as briefly described in the following parts; a stay suture was placed through the glans for trac- tion. Afterwards, the penis was degloved and two paral- lel incisions were made on the glans to form the glanular wings. One midline deep incision was carried out in the ure- thral plate as described by Snodgrass.(4) Finally, the plate measured at least 13 mm in width. At first, incised urethral plate was tubularized over a 8 Fr catheter with 6-0 polyg- lactin suture and these patients were classified into group B. Afterwards, tubularization was made over a 6 Fr catheter in order to decrease meatal stenosis in group A. Neomeatus was given a slit-like shape in order to avoid stenosis. Mo- bilized divergent corpus spongiosum was approximated in the midline to cover neourethra. The glans wings were re- approximated with no tension and the skin was closed. The catheters were removed 7 days after surgery. Children in both groups were evaluated for 1 year (every fortnight for 1 month and then once a month and also when- ever a specific problem appeared) in the postoperative pe- riod. Diagnosis of meatal stenosis was made according to the history given by parents (difficulty in urination, narrow and high flow of urinary stream, pain during urination, and the need to sit or stand back from the toilet bowl to urinate), inspection of meatus (circular, small and narrowed shape) and calibration of meatus. Under local anesthesia, urethral sounding was performed on the postoperative 15th day, 1st, 3rd and 6-month and 1st year. The caliber of the meatus smaller than the normal minimal size for a given age group was regarded as meatal stenosis.(5) Under general anesthe- sia, dilatation was performed when meatal stenosis was de- termined. Twenty eight (63.6%) of the patients in group A and 23 (59.0%) of the patients in group B were not yet potty trained. So, we were not able to performed uroflowmetry in these patients and we did not use uroflowmetry as a diag- nostic tool. Data collected included age, the location of hypospadias, dehiscence, urethrocutaneous fistula formation, urethral meatal stenosis formation and number of meatal dilatation in each patient. The statistical analyses were made using the statistical package for the social science (SPSS Inc, Chicago, Illinois, USA) version 11.5. The results were expressed as mean ± standard deviation (SD). Mann-Whitney U and t tests were used for the statistical analysis. P < .05 was accepted as statistically significant. RESULTS Patients’ characteristics and results are summarized in Table. There were no significant differences between the groups according to their age (P = .489). In group A, the location of hypospadias was distal penile in 34 patients (77.3%) and mid-shaft in 10 (22.7%). In group B, it was distal penile in 29 patients (74.4%) and mid-shaft in 10 (25.6%). There Pediatric Urology 1097Vol. 10 | No. 4 | Autumn 2013 |U R O LO G Y J O U R N A L The Effect of Urethral Catheter Size in TIPU | Karakus et al were no significant differences between the groups accord- ing to the location of urethral meatus (P = .758). In group A, urethrocutaneous fistula occurred in 2 (4.5%) of the patients and 3 (7.7%) of the patients in group B. There were no significant differences between the groups accord- ing to the urethrocutaneous fistula formation (P = .550). There was no dehiscence in either group. Urethral meatal stenosis occurred in 1 (2.3%) of the patients in group A and 6 (15.4%) of the patients in group B. Meatal stenosis formation in group B was markedly higher than that in group A (P = .033). All the meatal stenosis were re- solved after dilatation program at the end of the first year. The mean of meatal dilatation number was 0.046 ± 0.30 in group A and 0.44 ± 1.07 in group B, it was higher in group B compared to group A (P = .030). DISCUSSION TIP urethroplasty, as described by Snodgrass in 1994, is the method of choice for treating distal and mid-shaft hypospa- dias.(4) The success rate has been reported to be 88 to 100%. (6,7) The meatal stenosis formation rate has been reported between 1% and 17% after TIP urethroplasty.(3,4,8) In TIP urethroplasty, some modifications such as the intactness of the anticipated dorsal lip of the neomeatus and creating a generous wide elliptical external meatus were reported in order to reduce the risk of fistula and meatal stenosis. (1,3,9) Another possible reason for meatal stenosis may be the tension of glans wings approximation. It is generally acknowledged that distal urethroplasty must not be consid- ered a separate procedure from glansoplasty. The size of the catheter determines the likelihood for meatal stenosis as it increases the tension exerted for glans approximation. Although uroflowmetry is a simple and non-invasive way of evaluating the dynamics of micturition, the calibration of the meatus, the history given by parents and the physical examination of the meatus were sufficient in the diagnosis of meatal stenosis.(10) In our study, there were no significant differences between the groups in terms of their ages. The urethral meatus cor- responds generally with age. Since the urethral meatus is the narrowest part of urethra in boys, the catheter size in hypospadias repair should be chosen according to the width of the narrowest part of urethra for a given age group. Yang et al calibrated the size of the urethral meatus by sounding and reported that the normal minimal size of the urethral meatus is 10 Fr in 88 uncircumcised boys aged 0-14 years. (5) Since the catheters used in both groups were smaller than 10 Fr, the selection of catheter size was made regardless of the age of the patients. Inflammation, the first phase of the wound healing, is of- ten accompanied by local interstitial fluid accumulation ex- pressed as edema.(11) Also, re-epithelialization begins in 24 hours after surgery. Neourethra covers 8 Fr catheter more tightly than 6 Fr. Therefore, using a 6 Fr catheter could pro- vide an adequate area for edema and an adherence of both raw sides of the wound. Increased need for regular dilata- tion after tubularization of incised urethral plate over a 8 Fr catheter can be explained by edema that caused a pressure injury on the urethral mea and by hindered re-epitheliali- zation. The critical period of healing after the TIP urethro- plasty is the first few weeks and using a large-sized cath- eter can separate both raw sides of incised plate resulting in secondary healing. In secondary healing, centripetally directed contraction reduces the area of the wound. Over time, meatal stenosis occurs. Delayed wound healing resulting from a foreign-body reac- tion to biomaterials have also been reported. Besides, bio- Table. Summary of patients’ characteristics and results. Group A Group B Number of patients 44 39 Mean age, years 4.82 ± 3.83 5.19 ± 3.83 Location of hypospadias, n (%) Distal Mid-shaft 34 (77.3) 10 (22.7) 29 (74.4) 10 (25.6) Urethrocutaneous fistula, n (%) 2 (4.5) 3 (7.7) Dehiscence, n (%) 0 (0) 0 (0) Urethral meatal stenosis, n (%) 1 (2.3) 6 (15.4) Number of meatal dilatation 0.046 ± 0.30 0.44 ± 1.07 1098 | 8. el-Kassaby AW, Al-Kandari AM, Elzayat T, Shokeir AA. Modi- fied tubularized incised plate urethroplasty for hypospa- dias repair: a long-term results of 764 patients. Urology. 2008;71:611-5. 9. Lorenzo A, Snodgrass W. Regular dilatation is unnecessary after Tubularized incised plate hypospadias repair. BJU Int. 2002;89:94-7. 10. Bazmamoun H, Ghorbanpour M, Mousavi-Bahar SH. Lubri- cation of circumcision site for prevention of meatal stenosis in children younger than 2 years old. Urol J. 2008;5:233-6. 11. Stamatas GN, Southall M, Kollias N. In vivo monitoring of cutaneous edema using spectral imaging in the visible and near infrared. J Invest Dermatol. 2006;126:1753-60. 12. Orenstein SB, Saberski ER, Klueh U, Kreutzer DL, Novitsky YW. Effects of mast cell modulation on early host response to implanted synthetic meshes. Hernia. 2010;14:511-6. 13. Weyhe D, Hoffmann P, Belyaev O, et al. The role of TGF-be- ta1 as a determinant of foreign body reaction to alloplastic materials in rat fibroblast cultures: comparison of different commercially available polypropylene meshes for hernia repair. Regul Pept. 2007;138:10-4. 14. Ritch CR, Murphy AM, Woldu SL, Reiley EA, Hensle TW. Overnight urethral stenting after tubularized incised plate urethroplasty for distal hypospadias. Pediatr Surg Int. 2010;26:639-42. materials increased early inflammation and fibrosis.(12,13) Ritch and colleagues reported no meatal stenosis in 49 pa- tients who underwent TIP urethroplasty with an overnight urethral stenting technique.(14) It can be the result of limited foreign-body reaction. Using a large-sized catheter leads to a foreign body reaction more often than a biomaterial does, and it can bring about increased early inflammation, edema and fibrosis resulting in meatal stenosis. CONCLUSION We recommend the tubularization of urethral plate over a small-sized (6 Fr) catheter. Also, following the tubulariza- tion over a large-sized catheter, it can be altered by a small- sized one. Using a small-sized catheter, regardless of the age of the patients, prevents meatal stenosis by reducing foreign body reaction and pressure injury and by hindering secondary healing. CONFLICT OF INTEREST None declared. REFERENCES 1. Jayanthi VR. The modified Snodgrass hypospadias repair: reducing the risk of fistula and meatal stenosis. J Urol. 2003;170:1603-5. 2. Elbakry A. Regular dilatation is unnecessary after tubular- ized incised-plate hypospadias repair. BJU Int. 2002;90:473- 4. 3. Stehr M, Lehner M, Schuster T, Heinrich M, Dietz HG. Tubu- larized incised plate (TIP) urethroplasty (Snodgrass) in pri- mary hypospadias repair. Eur J Pediatr Surg. 2005;15:420-4. 4. Snodgrass W. Tubularized incised plate urethroplasty for distal hypospadias. J Urol. 1994;151:464-5. 5. Yang SS, Hsieh CH, Chen YT, Chen SC. Normal Size of the Ure- thral Meatus in Uncircumcised Boys. J Urol Roc. 2001;12:20- 2. 6. Chen SC, Yang SS, Hsieh CH, Chen YT. Tubularized incised plate urethroplasty for proximal hypospadias. BJU Int. 2000;86:1050-3. 7. Yang SS, Chen YT, Hsieh CH, Chen SC. Preservation of the thin distal urethra in hypospadias repair. J Urol. 2000;164:151-3. Pediatric Urology