Small intestinal submucosa for patch grafting after plaque incision in the treatment of Peyronie's disease

Objective: Report the results using porcine small intestinal submucosa (SIS) as a graft material in the surgical management of Peyronie’s disease (PD). Materials and Methods: We performed a retrospective chart review of men with PD who underwent surgical correction of the curvature by plaque “H” incision and patch grafting with 4-ply SIS (Cook, Bloomington, IN) by a single surgeon at our institution. Degree and direction of curvature, sexual function, and co-morbidities were assessed preand postoperatively. Results: Thirteen patients were identified. Mean age was 57 ±� ��� range ���7�� �ears. Median �����w��p was �� ��nths , range 3��9 ��nths. At presentati�n�� a�� rep�rted peni�e c�rvat�re. A�s� rep�rted were di�fic��t� with vagina� penetrati�n (deter�ined b� q�esti�n n��ber � �� the sex�a� enc��nter pr�fi�e q�esti�nnaire – SEP�)�� pa�pab�e p�aq�e�� h��rg�ass de��r�it��� di�fic��t� with fir�ness�� and di�fic��t� with s�staining erecti�n (deter�ined b� SEP3) in77%�� 69%�� 77%�� 6�%�� and �6% �� patients�� respective��. Mean and �edian degrees �� c�rvat�re �� the pri�ar� de��r�it� were 7� and 67.5 degrees�� respective��. Three patients had sec�ndar� c�rves �� �ess than 3�� degrees in a di��erent directi�n. Mean and �edian p�aq�e size were 3.5 and �.7 c�2, respectively. Seven patients had one graft and six patients had tw� gra�ts p�aced with a �ean size �� �5 ±� �� c� 2. Conclusions: For the patient with PD, SIS grafting can achieve a functionally straight erection with durable results yet with relatively high rates of erectile dysfunction. SIS is a viable graft material for use in the surgical treatment of PD.


INTRODUCTION
Peyronie's disease (PD) is a condition of plaque formation in the tunica albuginea of the corpora cavernosa with resultant curvature of the penis (�). The disease has tw� phases; an ear�� ac�te phase associated with painful erections and progression of deformity, and a later chronic phase in which the pain ceases and the de��r�it� is stabi�ized. C�nservative medical therapy is the initial treatment of choice for patients with acute phase disease. A variety of medi-cati�ns has been �ti�ized inc��ding vita�in E�� para� a�in�benz�ate p�tassi���� ta��xi�en�� c��chicine�� and verapamil. In addition to oral therapy, intralesional injections and various forms of energy have been applied for the treatment of PD (2). Few medical therapies have been proven effective in large scale trials. Surgical correction is the treatment of choice when the deformity precludes intercourse, but should not be considered until the disease has reached its stable, chronic phase.
Surgical options for the management of PD can be divided into 3 types: procedures that shorten the convex, uninvolved side of the tunica albuginea, procedures that lengthen the concave, diseased side, and i�p�antati�n �� a peni�e pr�sthesis (3). E��ipsoid resection and closure of the tunica albuginea �n the hea�th� c�nvex side�� as first described b� Nesbit, was the previous standard for surgical care (4). Subsequently, successful variations including a Heineke�Mik��icz pr�ced�re and ���tip�e para��e� p�icati�ns have been rep�rted (5��6). These pr�ced�res are limited by a shorter postoperative penile length that precludes their use in patients with large plaques, severe deformities, or small penises (3). For these patients, superior results may be obtained using tunical lengthening procedures where incision or excision of the tunical plaque is followed by interposition of a graft material to bridge the resulting defect in the t�nica. P�aq�e incisi�n �ti�izing a�t���g��s �ateria�s such as saphenous vein as patch grafts for the incised defect has been reported to result in high rates of patient satis�acti�n (7���). Drawbacks t� a�t���g��s grafting are the increased morbidity of a secondary tissue harvest site and increased OR time required for tissue procurement and preparation.
Non-autologous "off the shelf" biomaterials are an attractive alternative to autologous tissue for patch grafting (3). At our institution we favor porcine small intestinal submucosa (Stratasis, Cook Urological, Spencer, IN), a xenographic biomaterial retaining matrix elements that support host cell migration and differentiation. There have been some preliminary reports describing the use of SIS in Peyronie's disease repair (9���). We present ��r instit�ti�n's experience with SIS gra�ts in �3 patients.

MATERIALS AND METHODS
Institutional review board approval was obtained for a retrospective chart review of men who underwent surgical correction of Peyronie's disease with plaque incision and patch grafting with 4-ply porcine small intestinal submucosa (Stratasis, Cook Urological, Spencer, IN) at our institution by a sing�e s�rge�n between March �999 and A�g�st �����6.
Follow-up data was collected by the operating s�rge�n at �����w��p ��fice visits. P�st�perative peni�e curvature, length, potency, use of erectile dysfunction medications, pain, and palpable plaque were recorded. Subjective (by patient) and objective (by physician) cosmetic and functional outcomes were recorded.

COMMENTS
Plaque incision and grafting is the procedure of choice for the treatment of severe Peyronie's disease. This precludes intercourse when patients have large plaques, severe curvature, or a short phallus, which makes the loss of penile length with plication procedures unacceptable. Autologous grafts such as saphenous vein have been used as patch grafts with satisfactory results. However, non-autologous grafts have the advantage of not requiring a second harvest site, decreasing operative time and patient morbidity as well as preserving graft material, such as saphenous vein, should the patient require coronary artery bypass surgery in the future.
In our study, concomitant penile plication was per��r�ed in �� �� �3 cases. In �rder t� prevent the need for plication in addition to the incision and gra�ting pr�ced�re�� we have since ��dified ��r s�r-gica� techniq�e. The SIS gra�t is �versized b� �3��% instead �� ����%�� and the H incisi�n is br�ader and �arger. M�re�ver�� we have started t� excise a s�a���� linear segment of the plaque before placement of the graft, a technique that other authors have found to negate the need ��r a sec�ndar� p�icati�n (�9).
Weaknesses of our study include a retrospective design�� s�a�� sa�p�e size�� and the �se �� subjective assessments of satisfaction and erectile function. Future studies on graft materials for the s�rgica� c�rrecti�n �� PD sh���d �ti�ize �bjective �eans �� characterizing peni�e b���d fl�w�� s�ch as power Doppler ultrasonography of the penis, and objective measures of rigidity and tumescence, such as Rigiscan® nocturnal penile tumescence.

CONCLUSIONS
The results of our experience using SIS in the repair �� Pe�r�nie's disease de��nstrate its e�ficacy in achieving a functional, straight erection with durable results. The advantages of SIS include ease of use and favorable biochemical characteristics as well as ready availability and lack of need for native tissue harvest with its attendant morbidity. Our study showed a relatively higher rate of venous leak erectile dysfunction than previously described, particularly in men with greater penile curvature at baseline. Larger st�dies investigating the tr�e rates �� erecti�e dysfunction using SIS as well as comparisons with other materials are warranted.