HOLLOWELL AND ASSOCIATES
Primary hypospadias repairs-complication rates (19821987) %
Meatal advancement and glanuloplasty Mathieu Onlay island flap Preputial island tube Double faced island flap Over-all complication rate
<1 10 8
The onlay island flap urethroplasty was described originally as an alternative to the meatal-based flip-flap urethroplasty for repair of distal hypospadias without chordee. 1 Advantages of the technique continue to be proved with time. The onlay island flap avoids the proximal penile shaft skin ~eficiency res_ulting from a meatal-based flap, which makes skm coverage m the Mathieu procedure more difficult. By not removing the ventral flip-flap, this extra shaft skin is available fo~ ventral shaft coverage and this, in turn, improves the cosmetic result. The onlay island flap repair is more applicable for cases of proximal hypospadias when a meatal-based flap mig~t be considered but would require incorporation of scrotal skm. Meatal stenosis is eliminated easily with the technique. Perhaps most importantly, successful repair is not dependent on the viability of the thin ventral shaft skin at the hinge of the meatus used in a Mathieu procedure. We believe that this deficient parameatal tissue and its precarious blood supply at the base of meatal-based flaps are a likely source of many of the problems seen with the Mathieu urethroplasty. Although the complication rates of the onlay island flap and meatal-based flap techniques were similar in our earlier report, additional experience with the onlay island flap has resulted in a slightly lower (8%) rate of complications. The use of vascularized preputial flaps in more severe hypospadias repair is preferred, in our experience, for construction of the neourethra. 5 •6 Subcutaneous blood supply to the ventral preputial skin is reliable and easily preserved, optimizing vascularity and subsequent healing. The onlay island flap urethroplasty evolved as a simplified version of its more complex precursor, the transverse preputial tubularized island flap urethroplasty. Advantages of the onlay island compared to the tubularized island flap urethroplasty include its ease in performance the immobilization provided by the urethral plate, which pr;vents kinking and tortuosity, and avoidance of circumferential anastomoses proximally and at the meatus making stricture and stenosis less likely. These techn_ical_ advantages have resulted in a significantly lower comphcat10n r~te with the onlay island flap compared to the transverse preputial island flap when applied to similar proximal hypospadias variants. The broadened applications of the onlay island flap urethroplasty represent a significant departure from o~r previous approach to the management of many cases of proximal hypospadias with and without chordee. Classically, excisio~ of cho~dee in attempts to eliminate penile curvature necessitates division of the urethral plate and pericorporeal excision of fibrous plaque. In our experience most mild degrees of ~urvature a~d glans tilt are corrected by takedown of the pei:ule shaft ski~. This procedure releases tethering caused by thm ventral skm and fibrous dartos fascia proximal to the meatus and preserves the urethral plate. In many patients mild degrees of persistent curvature are not resolved by dividing the urethral plate and dissecting behind it. More aggressive attempts to straighten the curved penis by ventral dissection of fibrous tissue, including splitting the corporeal septum, may result in secondary ~earring and residual ventral curvature. We currently are less likely to persist with this approach and have turned to correction of persistent mild or moderate chordee by adjunctive dorsal plication maneuvers when the urethral plate is well developed. Opposite the point of curvature, 2 parallel nonabsorbable su-
tures are placed about 8 to 10 mm. apart on the dorsolateral aspect of each corpora at the 10 and 2 o'clock positions. The neurovascular bundles are identified and avoided by lateral-tomedial dissections of Buck's fascia at these points. The tunica albuginia is not excised but merely plicated. An artificial erection confirms straightness. We have not had neurological complications with this technique. If the urethral plate has been divided the onlay island flap cannot be used and a more extensive urethroplasty, usually in combination with a dorsal straightening maneuver, becomes necessary. Other options for alleviating persistent curvature include insertion of dermaF or tunica vaginalis 4 grafts, removing wedges of dorsal tunica albuginea and reapproximating the defect,3 and dorsal plications with permanent sutures (our preference). Dorsal plication sutures are simply done, sacrifice little in the way of penile length and have withstood time in correction of chordee. Significantly, they allow for preservation of the dorsal urethral plate and use of the onlay island flap urethroplasty. Careful inspection often reveals that the dorsal urethral plate is well developed and can be preserved. We currently recommend in cases of proximal and mid shaft hypospadias with mild or moderate chordee to avoid urethral plate division initially until it is certain that such a maneuver is necessary for an attempt at complete chordee release. When the plate is developed poorly and may be contributing to chordee it should be divided. Otherwise, when mild curvature persists after pericorporeal dissection we prefer to plicate the corpora and perform onlay island flap urethroplasty. The onlay island flap is not suitable for every hypospadias variant. More severe chordee still is treated by a standard division of the dorsal urethral plate and dissection of chordee tissue. The tubularized transverse preputial island flap urethroplasty continues to be used for approximately 60% of the proximal cases and will remain a mainstay for treatment of hypospadias with significant chordee. However, we recognize that many patients with proximal hypospadias without chordee, and many with mild and moderate chordee may benefit from the simpler onlay island flap urethroplasty with its technical advantages and lower complication rate. Although the longterm implications of preserving a well developed urethral plate are unknown, we suspect that use of the onlay island flap in these patients will show continued good results with time. REFERENCES 1. Elder, J. 8., Duckett, J. W. and Snyder, H. M.: Onlay island flap in the repair of mid and distal penile hypospadias without chordee. J. Urol., 138: 376, 1987. 2. Duckett, J. W.: MAGPI (meatal advancement and glanuloplasty): a procedure for subcoronal hypospadias. Urol. Clin. N. Amer., 8: 513, 1981. 3. Nesbit, R. M.: Congenital curvature of the phallus: report of three cases with description of corrective operation. J. Urol., 93: 230, 1965. 4. Das, 8.: Peyronie's disease: excision and autografting with tunica vaginalis. J. Urol., 124: 818, 1980. 5. Duckett, J. W.: Hypospadias. In: Adult and Pediatric Urology. Edited by J. Y. Gillenwater, J. T. Grayhack, 8. 8. Howards and J. W. Duckett. Chicago: Year Book Medical Publishers, vol. 2, chapt. 57,pp. 1880-1915, 1987. 6. Duckett, J. W., Jr.: Transverse preputial island flap technique for repair of severe hypospadias. Urol. Clin. N. Amer., 7: 423, 1980. 7. Horton, C. E. and Devine, C. J., Jr.: Peyronie's disease. Plast. Reconstr. Surg., 52: 503, 1973. EDITORIAL COMMENT The authors deserve credit for their ongoing contributions to the study of hypospadias. However, I do have some concerns about the long-term application of the technique reported. Is there a risk that the urethral plate, which may be intrinsically abnormal in the more proximal forms of hypospadias, will fail to grow normally and, thus, cause chordee at a later date? I recently operated on a 25-year-old man with distal shaft-coronal hypospadias associated with moderately severe chordee that reportedly was not present previously.
PRESERVATION OF URETHRAL PLATE
I have ahvays had misgivings about dorsal corporeal excision or plication in small children, fearing neurovascular injury. The authors report no "neurological complications with this technique". I would be most interested to learn how they determined this in small children. Additionally, is plication really long-lasting and, if it is, will the permanent sutures used act as an irritant, since so little subcutaneous tissue is present in the penis? It seems to me that if dorsal shortening is elected then excision of fascia with reapproximation using longlasting but ultimately absorbable suture would be preferable. However, as a urologist I always have felt more comfortable lengthening rather than shortening the penis. A. Barry Belman Department of Urology Children's Hospital National Medical Center Washington, D. C.
REPLY BY AUTHORS
Judgment of the elasticity and normalcy of the urethral plate is made when the artificial erection is done and the plate remains soft, pliable and healthy. Obviously, the fibrous chordee with more proximal severe forms of hypospadias requires excision and this decision depends on experience. We are reporting that a surprising number of proximal cases are amenable to the onlay island flap technique with preservation of the plate. One must start with this incision so that, after the artificial erection, one may still excise the plate if necessary. Experience with dorsal plication has made us confident that we can avoid neurovascular injury and not shorten the penis. Similar results are reported with treatment of mild Peyronie's disease with plication techniques with no sexual compromise. As Doctor Belman states, whatever the "hypospadiologist" is "more comfortable" with, he will advocate either positively or negatively.