Related Experiment Video
Updated: Jun 28, 2026
Vessel-sparing Excision and Primary Anastomosis
Published on: January 7, 2019
Neo-modified Koyanagi technique for the single-stage repair of proximal hypospadias
Yutaro Hayashi1, Yoshiyuki Kojima, Kentaro Mizuno
1Department of Nephro-urology, Nagoya City University, Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan. yutaro@med.nagoya-cu.ac.jp
Purpose:
To retrospectively analyze the results of a modification of the Koyanagi hypospadias repair developed to reduce complications.
Materials And Methods:
Twelve boys underwent a modified Koyanagi repair over the past 3 years. The technique included the preservation of a wide vascular pedicle for each parameatal flap. The distal urethral plate was left intact and attached on each lateral side to the medial side of each distal Koyanagi pedicle flap.
Results:
One boy (8%) developed a urethral fistula. There was no instance of meatal stenosis, sacculation or urethral stricture.
Conclusions:
Modifying the Koyanagi repair by preserving a wide vascular pedicle for the distal skin flaps and utilizing the distal urethral plate as the base for the distal neourethra has lowered the incidence of complications. This technique is a suitable alternative to a two-stage approach for the correction of proximal hypospadias.
