Objective: To compare the outcomes of three different urethroplasty techniques (onlay, buccal mucosa, Koyanagi type I) used in the reconstruction of severe hypospadias.
Patients and methods: Over 10 years (1997-2007), 300 severe hypospadias cases were treated with a mean follow up of 2 years (1-105 months); 203 were operated by the same surgeon of whom 184 completed follow up. Three main techniques were used according to the quality of the urethral plate: onlay urethroplasty (133), buccal graft urethroplasty (25) and Koyanagi type I (26). The mean age at surgery was 36 months (8-298); 76 required preoperative androgen stimulation (onlay 37, buccal 11, Koyanagi 26); 18 required a corporoplasty to straighten the penis (onlay 13, buccal 3, Koyanagi 2).
Results: Thirty-eight onlay (28.5%); 14 buccal (56%); 16 Koyanagi (61.5%) urethroplasties had a complication. The fistula rate was 15% for the onlay group; 32% for the buccal mucosa group; 19.2% for the Koyanagi cases. The dehiscence rate was, respectively, 11.3%, 20% and 42.3%. The stricture rate was, respectively, 1.5%, 20% and 34.6%. Urethrocele was found in seven Koyanagi patients. Final functional and cosmetic results were satisfactory in 126/133 (94.7%) onlay, 20/25 (80%) buccal and 14/26 Koyanagi (53.8%) urethroplasties. Primary cases had better results (89%) than redo cases (75.9%). Patients submitted to preoperative androgen therapy developed more complications (onlay: 40.5% vs 23.9%; buccal: 70% vs 43.7%).
Conclusion: Two striking results are the low number of severe hypospadias cases requiring an additional corporoplasty, and the increased complication rate found in androgen-stimulated patients. The excellent results of the onlay procedure could be related to the use of dorsal preputial tissue, which in hypospadias is characterized by a well-balanced protein platform compared to the ventral tissues.