Original Koyanagi urethroplasty versus modified Hayashi technique: Outcome in 57 patients

Choosing a technique for severe hypospadias

“…Complication rates for the Koyanagi procedure in other series vary from 20 to 60% even in expert hands. [7,9,15,[19][20][21] But again, even if the complication rate is high, these are benign complications; we have not observed any strictures or residual chordee. This technique always allows for sufficient ventral tissue for the secondary operation if necessary.…”

“…This is in agreement with the series reported by Catti et al, where they remarked that division and proximal mobilisation of the plate allowed them to achieve complete penile straightening in 89% of cases. [19] Finally, when complications do occur following the modified Koyanagi repair, there is always sufficient tissue available on the ventral aspect for the redo-operation.…”

Modified Koyanagi's procedure for proximal hypospadias: Our experience

“…Catti et al. 10 compared outcomes of the original Koyanagi technique with the Hayashi modification in severe hypospadias and concluded that although the complication rate was quite similar in both groups, the Hayashi technique seemed to provide a better distal blood supply to the reconstructed urethra.…”

Long-term outcome of hypospadias surgery

“…(2) Koyanagi technique and the Hayashi modification [23] technique reviewed were compared showing a very similar number of complications (around 60%). The Hayashi technique has less urethral dehiscence and stenosis than the original Koyanagi technique.…”