1.Prefabricated Urethra With Oral Micro-mucosa And Gelatin Sponge 2.Urethral Reconstruction Using Gelatin Spongy And Micro-mucosa Graft Combined With Local Flap

1.Prefabricated urethra with oral micro-mucosa and gelatin spongeHypospadias is one of the most common congenital deformities of male genitourinary system.Distal urethral defect is the main manifestation.Urethral reconstruction requires adequate amounts of tissue and donor-site morbidities occured common by using autologus tissue.We graft the gelatin sponge together with micro-mucosa which taken from buccal mucosa to the subcutaneous capsule.Then we implant soft tissue expander under the graft to prefabricate the urethra lined by mucosa.Objective:We investigated the survival and inversion of the compound graft(gelatin sponge and micro-mucosa) to the capsule and measure the rate of contracture.Further study were also made to against the contracture such as adding BMSC and combining with flap.Materials and methods:1.We cut the free buccal mucosa into particles,the diameter of which is less than 1mm, spread onto the gelatin sponge and then transplant to the capsule,the experimental group was divided into three subgroups(GroupⅠ,ⅡandⅢ) with area expansion ratio of autogenous micro-mucosa 4:1,8:1 and 16:1 respectively.We implant the soft tissue expander under it and keep 40mmHg in it.The control group was only implanted soft tissue expander without mucosa graft.Macroscopy and histological samples by HE and immunohistochemical staining were examined on the 7th,14th,21th and 28th day after the grafting.SEM examination was taken on the 28th day.We observed the tissue harvested from the samples on the 150th day after grating to investigate the inversion of the grafted mucosa.2.We prefabricate the capsule in advance when measure the contraction of grafts.5 groups(Ⅴ,Ⅵ,Ⅶ,ⅧandⅨ) were made.The autogenous micro-mucosa graft(expansion rate 8:1)was served as groupⅤgroupⅥwas the same ratio but adding BMSc.We transplanted free skin graft taken from groin in groupⅦand micro-mucosa combined with local flap in groupⅧ.GroupⅨwas blank control.All the groups were keeping stent for 3 weeks by the tubes and measured the contraction after 3 weeks.Results:1.All the wounds were not healed completely after one week grafting,though some of the mucosa survived and its epithelial cells grew into the gelatin sponge,and the wound healing rates were different.On the 14th day after grafting,The wound healing rates of groupⅠandⅡwere more than 90%and higher than groupⅢ(p＜0.05),however,there's no obvious difference between groupⅠandⅡ.All the wound healing rates were more than 90%0 on the 21th day.There's no obvious difference between 2 weeks and 3 weeks after grafting in groupⅠand groupⅡ,however groupⅢhad the difference(P＜0.05).All the three groups had the obvious difference between one week and two week after grafting(P＜0.01).2.The CK were observed with immuneohistochemistry in wound tissue specimens so as to confirm epithelial tissue among all the experimental groups before 4 weeks.We could find stratified squamous epithelium on 21th day and the cells presented obvious polarity. However,immunohistochemical staining of certain antibody were negative in 5 months after grafting and the polarity disappeared. 3.The gelatin sponge was not absorbed on the 7th day.We could also find some gelatin sponge exist 4 weeks after grafting.4.All the groups encountered the contraction,however groupⅧwas better than the others.Conclusion:1.The oral micro-mucosa and gelatin spongy graft can survive on the expanded capsule.2.The quality of compound graft is best between 2 weeks and 3 weeks after grafting. The cell degeneration can be found in the long time.3.We could find stratified squamous epithelium on 21th day and the cells presented obvious polarity.The stratified squamous epithelium is thick,because epithelial cells grew into the gelatin sponge.4.All the groups encountered the contraction after removing the silicone tubes. 2.Urethral reconstruction using gelatin spongy and micro-mucosa graft combined with local flapHypospadias is one of the most common congenital deformities of male genitourinary system and the surgical treatment is the only method for repairing hypospadias.Objective:It has been popular to repair hypospadias by using the tubularized incised plate(TIP) urethroplasty and onlay island flap urethroplasty in recent years because of their low complication rates and satisfied cosmetic and functional results.However,both of the urethroplasties are not applicable to proximal hypospadias with severe chordee.The purpose of our study is to contrive a new method to repair proximal hypospadias by combining micro-mucosa which taken from inner prepuce or urethral plate with local flap to reconstruct urethra and describe the clinical feasibility and value of this method. Moreover,we compare our method with the other ones such as combined use of scrotal skin graft and local flap.Methods:From April 2006 to December 2007,18 cases of congenital hypospadias were operated using our method by the same surgeon.The average age was 21 months old(8 months to 36 months).The meatus located at the penoscrotal angle or scrotum and deep chordee was all presented.We divided all the cases into 2 groups(8 cases in groupⅠand 10cases in groupⅡ).GroupⅠwere repaired by combined use of micro-mucosa which taken from inner prepuce or urethral plate and local flap to reconstruct urethra.Only one of the 8 cases was undergone two-staged operations because the meatus located at the proximal scrotum.GroupⅡwere repaired by combined use of scrotal skin graft and prepucial flap to reconstruct urethra.3 of the 10 cases were undergone two-staged operations.A free micro-mucosa was transplanted to the corpora cavernosa and covered with gelatin sponge.Temporary urethral stent tube which had lateral apertures were used for about 14 days after first operations and used for 6 months after second staged operations.All the patients were followed up and some of them were examined using urethroscopy postoperatively.Results:Patients in groupⅠwere followed up after surgical repair for 2～24 months and in groupⅡfor 6-30 months.All the cases were successful without urethral fistula and urethral stricture postoperatively.It took about 150±35.0 min of groupⅠand 200±45.0 min of group2 to complete this operation.The length of absent urethra was about 2.5cm～4.5cm (average length was 3.38±0.79cm) which measured during the operations.Both of the methods corrected the down curvature and created a vertically oriented,slit-like meatus at the tip of the glans and satisfactory voiding function.The appearance of penis resembled the appearance after prepuce circumcision.All the patients could normal urination and erection.Superficial penile curvature occurred in one case respectively of two groups after one year postoperatively without further repair.One case in groupⅠhad needle fistula but self-cure.The neomeatus of one case in groupⅡhad split and retruded so as to take further repair.there's no obvious disparity of complication rates between two groups.2cases in either group were undergone urethroscopy follow-up.GroupⅠpresented smooth urethral wall,normal urethral caliber and good compliance.Conclusion:Our method could repair the proximal hypospadias which combined micro-mucosa taken from inner prepuce or urethral plate and local flap.The complication rates are approached to the groupⅡ.The neourethra was not easy to curvature because of the support of corpus cavemosum.We didn't resect the urethral plate to avoid the stenosis of anastomosis and urethral expansion.A vertically oriented,slit neomeatus was gained after operation and the appearance of the glans was satisfied.Furthermore,hair growth couldn't been found in the urethra after puberty.The advantages of our method are to decrease the utilization of local tissues,improve the appearance of glans and decrease the complication rates.However,the time of follow-up is not adequate,so we have to make further investigations after long peiod.