Cadaveric Dermis Research Articles

Decellularized human cadaveric dermis provides a safe alternative for primary inguinal hernia repair in contaminated surgical fields

Background Repair options for inguinal hernias in contaminated surgical fields include local tissue repair or mesh repair. The former is associated with higher hernia recurrence rates. The latter generally is avoided because of an unacceptably high infection rate. AlloDerm (Lifecell Corp., Branchburg, NJ) can potentially provide a strong repair resistant to infection. The aim of our study was to evaluate if AlloDerm provides a safe alternative for inguinal hernia repair in contaminated surgical fields. Methods We retrospectively reviewed the medical records of all patients who underwent inguinal hernia repair with AlloDerm from December 2004 to April 2006. Demographics, risk factors, perioperative data, and recurrence rates were evaluated. Results Twelve patients with contaminated surgical fields underwent inguinal hernia repair with AlloDerm. Serious perioperative complications occurred in only 1 patient. Two patients developed superficial wound infections (treated conservatively). There were no mortalities. No hernia recurrence has been documented with a follow-up period of 3 to 17 months (median, 9 mo). Conclusions AlloDerm provides a safe alternative for inguinal hernia repair in contaminated surgical fields.

Transperineal Repair of Persistent Rectovaginal Fistulas Using an Acellular Cadaveric Dermal Graft (AlloDerm®)

A number of surgical techniques have been described to treat rectovaginal fistulas. Recurrent or persistent fistulas after previous repair can be particularly difficult to treat. We report a novel technique used to successfully repair rectovaginal fistulas after failed mucosal advancement flap procedures using a transperineal-layered closure with an interposed graft of acellular cadaveric dermis (Alloderm).

1322: Inlay Repair with Cadaveric Dermis: A New Technique for Repair of Distal Extrusion of Penile Cylinder

1322: Inlay Repair with Cadaveric Dermis: A New Technique for Repair of Distal Extrusion of Penile Cylinder

Comparison of Biomechanical Properties of Alloderm and Enduragen as Static Facial Sling Biomaterials

Static slings are one of the most commonly used surgical rehabilitation methods in the management of chronic facial paralysis. Acellular human cadaveric dermis (Alloderm; Life Cell Corp., Branchburg, NJ) is used for this purpose; however, it has variable stretching properties that may necessitate additional "tuning-up" procedure(s). Acellular porcine dermis (Enduragen; Tissue Sciences Laboratories, plc., Aldershot, U.K.) was recently introduced as a biologic implant and it is compositionally similar to Alloderm. However, no data currently exist regarding its biomechanical properties and potential use as an alternative implant to Alloderm in static facial sling procedures. The objective of this study was to compare the biomechanical properties of Alloderm and Enduragen for static facial sling procedures in the management of the paralytic face. This study consisted of an in vitro prospective study in an academic medical research setting. Same size and thickness Alloderm and Enduragen samples were tested with MTS 858 Bionix materials test system for load-to-failure, displacement under increasing and constant stress, and stiffness. Enduragen showed significantly less elongation under increasing stress and at the beginning of constant stress. Load-to-failure and stiffness were significantly higher in Alloderm; however, both biomaterials have adequate stiffness and load-to-failure for a static facial sling procedure. Enduragen may serve as another potential static facial sling material, because it stretches significantly less than Alloderm under stress. Clinical experience is needed with Enduragen to determine its potential use as a static facial sling material.

Pelvic, Abdominal, and Chest Wall Reconstruction with AlloDerm in Patients at Increased Risk for Mesh-Related Complications

The use of polypropylene mesh in the reconstruction of trunk defects increases complication rates when the mesh is placed directly over viscera or the operative site has been irradiated or contaminated with bacteria. An alternative is AlloDerm (decellularized human cadaveric dermis), which becomes vascularized and remodeled into autologous tissue after implantation. When used for fascial reconstruction, AlloDerm forms a strong repair, causes minimal abdominal adhesions, and resists infection. We did a retrospective study of cancer patients at increased risk for mesh-related complications who underwent trunk reconstruction with AlloDerm over a 1-year period. Risk factors included unavoidable placement of mesh directly over the bowel or lung, perioperative irradiation, and/or bacterial contamination of the defect. The indications, defect characteristics, reconstructive techniques, complications, and surgical outcomes were evaluated. Thirteen patients were included in the study. Indications for reconstruction were oncologic resection, resection of enterocutaneous fistula, and/or ventral hernia repair. Seven patients had bacterial contamination at the operative site and seven patients received perioperative radiation. The mean musculofascial defect size was 435 cm. AlloDerm was placed directly over the bowel or lung in all patients. Nine patients required flap reconstruction, including 14 pedicled and two free flaps. The mean follow-up was 6.4 months. Complications occurred in six patients, however, there were no clinically evident mesh infections, hernias, or bulges. AlloDerm successfully can be used in reconstructions for large, complex pelvic, chest, and abdominal wall defects even when placed directly over viscera and when the operative field is irradiated and/or contaminated with bacteria.

Solvent‐dehydrated cadaveric dermis: a new allograft for pubovaginal sling surgery

The aim of this study was to evaluate the efficacy of solvent-dehydrated cadaveric dermis in pubovaginal sling surgery for the first time in the literature. Twenty-five women with stress urinary incontinence underwent pubovaginal sling surgery using 2 x 12 cm allograft dermis. Preoperatively, all patients were evaluated by a detailed urogynecologic evaluation, voiding diary, pelvic examination and urodynamic investigation. Outcome was assessed by the Urogenital Distress Inventory short form and standardized follow-up questionnaires. Twenty (80%) patients were cured of stress incontinence symptoms. Seventeen wore no pad and three reported occasional stress urinary incontinence and used no or one pad at a mean follow up of 12 months. Five (20%) patients in our series experienced the same amount of leakage as before the surgery. Seventy-six percent of the patients indicated that urinary incontinence was no longer negatively affecting their daily life and were satisfied with the procedure. Questionnaire-based assessment of outcome suggests that solvent-dehydrated cadaveric dermis is effective in the treatment of stress urinary incontinence. However, larger and comparative prospective studies with long-term results and randomized comparison of tissue preparation techniques are warranted.

Refractory pyoderma gangrenosum peristomal ulcer and sinus tract treated with micronized cadaveric dermis

Refractory pyoderma gangrenosum peristomal ulcer and sinus tract treated with micronized cadaveric dermis

Biomechanical properties of materials used in static facial suspension.

To compare the biomechanical properties of the superficial (human acellular dermis); (AlloDerm; LefeCell Corp, Branchburg, NJ) and deep layers of cadaveric dermis and expanded polytetrafluoroethylene (ePTFE); (Gore-Tex; W. L. Gore & Associates, Flagstaff, Ariz). Sixteen samples of superficial dermis (AlloDerm), 12 samples of deep dermis, and 12 samples of ePTFE were axial loaded on a materials testing machine. Maximum load to failure and stiffness were calculated and statistical analysis was performed to compare the materials. Dermis samples had statistically greater mean stiffness compared with ePTFE samples. There was no statistical difference of maximum load to failure comparing ePTFE with superficial dermis. There was a statistical difference in maximum load to failure between ePTFE and deep dermis. There was no statistical difference between the superficial and deep layers of the dermis with respect to stiffness or maximum load to failure. Cadaveric dermis has some biomechanical properties to be a superior material for static facial suspension. There was larger than expected variability in both parameters (stiffness and maximum load to failure) tested in dermis samples, which may correlate with occasional clinical failure.

Poster 8: Development and characterization of tissue-engineered oral mucosa using cryopreserved oral keratinocytes

Poster 8: Development and characterization of tissue-engineered oral mucosa using cryopreserved oral keratinocytes

Small intestinal submucosa does not promote PAIII tumor growth in Lobund-Wistar rats

Background Site-specific remodeling and angiogenesis are two observations associated with the use of small intestinal submucosa (SIS) as a tissue repair graft. Its angiogenic capacity has raised questions concerning its effect on tumor growth and metastasis in clinical tumor resection cases. The effect of SIS on the ability of neoplastic (prostate adenocarcinoma) cells to establish, grow, and metastasize was examined in Lobund-Wistar (L-W) rats. Materials and methods In one study, SIS, expanded polytetrafluoroethylene (ePTFE), or human cadaveric dermis was placed in a subcutaneous pocket on the flank of L-W rats and immediately inoculated with PA-III cell suspension. Tumors were allowed to establish and metastasize for 5 weeks prior to sacrifice. Rate of tumor growth, tumor weight, and frequency of lung metastases were assessed. In a second study, SIS was placed in a resected tumor bed and tumors were allowed to recur. Rate of tumor growth, tumor weight, and frequency of lung metastases were assessed after 3 weeks. Results ePTFE hastened the rate of formation of palpable tumors compared to controls and other materials; cadaveric dermis and SIS did not. No differences between materials were noted in final tumor weight nor in the frequency of metastasis to the lungs. Following surgical tumor resection, residual tumor cells led to recurrence of same-site tumors in all animals, but in the defects augmented with SIS, the tumors were significantly smaller than those which regrew in the resected, unaugmented group. Conclusions This study demonstrates that SIS does not enhance tumor establishment, growth, or metastasis in de novo tumors. Furthermore, SIS appears to reduce the rate of tumor growth, but not metastasis, when applied in direct contact with a residual tumor bed in a rat model of prostate-related tumors.

PORCINE DERMIS INTERPOSITION GRAFT FOR REPAIR OF HIGH GRADE ANTERIOR COMPARTMENT DEFECTS WITH OR WITHOUT CONCOMITANT PELVIC ORGAN PROLAPSE PROCEDURES

Recent literature suggests that graft interposition may decrease the incidence of cystocele recurrence. We describe our experience with porcine dermis interposition grafts for the repair of high grade cystoceles. We retrospectively reviewed the charts of all women who underwent surgical repair of high grade cystocele. Prolapse was graded with the Baden-Walker and Pelvic Organ Prolapse Quantitation systems, and all patients were evaluated with multichannel videourodynamics. Concomitant stress urinary incontinence was corrected with a pubovaginal sling and vault prolapse was corrected with iliococcygeus vault suspension. Postoperatively patients were evaluated at 2 weeks, 2 months, 6 months and annually thereafter. A total of 70 patients underwent cystocele repair with a porcine dermis interposition graft. Concomitant procedures included a pubovaginal sling in 65 patients and vaginal vault suspension in 50. Mean followup was 24 months. There were no intraoperative complications. Of the patient 59 (91%) are currently dry. One patient had recurrent vault prolapse without cystocele (C -2), which was successfully repaired with abdominal sacral colpopexy. Six patients (8.6%) experienced recurrent grade II (Ba 0) cystocele but continued to be asymptomatic. Three others (4.3%) had recurrence of grade III (Ba +2) cystocele and elected not to undergo reoperation. Two of 6 de novo rectoceles (grade II, Ap and -1 and Bp 0) were repaired with site specific repairs. Superficial vaginal wound separation in 1 case was successfully treated conservatively. In cases of high grade cystocele interposition of porcine dermis represents a successful and safe treatment option. Cystocele recurrence is typically low grade and it frequently may not require additional surgery.

Acellular cadaveric dermis (AlloDerm): a new alternative for abdominal hernia repair.

AlloDerm is an intact human tissue matrix with the critical biochemical and structural components of the dermal extracellular scaffold that enable it to recellularize and revascularize. Its biologic nature provides AlloDerm with an improved capacity to reintegrate with surrounding tissues and less inclination toward infection, erosion, extrusion, and rejection compared with synthetic tissue replacement materials. This retrospective review describes the experience with AlloDerm for incisional hernia and transverse rectus abdominis musculocutaneous flap reconstructions at a plastic surgery practice that handles complex, nonprimary repairs. AlloDerm was observed to provide exceptional safety and tolerability, and to become reintegrated and vascularized with surrounding tissue for tolerable and persistent tissue replacement.

Pubovaginal sling using Duraderm graft: intermediate follow-up and patient satisfaction.

To assess outcome and patient satisfaction utilizing Duraderm allograft as sling material. Twenty five patients undergoing the Duraderm sling procedure were evaluated by pelvic examination, post-void residual urine, and multi-channel urodynamics. Follow-up included repeat examination, stress test, and chart review. Patient satisfaction was assessed by phone interview with an independent examiner. Outcome was defined as dry (no leaking at all and patient perception of satisfaction), improved (minimal leak requiring < or =1 pad daily and patient perception of satisfaction), or failure. Average age was 62.0 years (30-83); average daily preoperative pad usage was 3.5 (2-8). Duraderm allograft measuring 2 x 12 cm was used. Mean postoperative catheter time was 7.7 days (3-37 days). At 6 months, 17/25 (68%) were dry, 6 (24%) improved, and 2 (8%) failed. Mean intermediate follow-up at 14.8 months (8-23 months) revealed 8/25 (32%) patients were dry, 9 (36%) were improved, and 8 (32%) failed Duraderm sling. Mean pad use after surgery was 1.4 (0-6). Of the 25, 19 (76%) were satisfied with the surgical outcome, 17 (68%) noted they would have surgery again, and 17 (68%) would recommend the procedure. Initial results of pubovaginal sling using Duraderm graft are satisfactory; however, longer term follow-up is disappointing. Graft degeneration previously described after utilization of cadaveric fascia lata may be possible following implantation of cadaveric dermis.

Implications of axillary sentinel lymph node biopsy in immediate autologous breast reconstruction.

For patients with invasive breast cancer, if the results of an axillary sentinel node biopsy are determined to be positive after permanent pathologic examination, the current recommendation is to perform a complete axillary node dissection. Subsequent axillary surgery may compromise the blood supply to an immediate autologous breast reconstruction. The purpose of this study was to determine which clinicopathologic factors in clinically node-negative breast cancer patients may be associated with an increased risk of positive axillary nodes. Identification of these factors will allow surgeons to modify their approach to immediate autologous breast reconstruction in these high-risk patients. The relationship between presenting clinicopathologic characteristics and the incidence of axillary metastases was analyzed by chi-square test and multivariate analysis in 167 patients with invasive breast cancer and a clinically negative axilla who underwent modified radical mastectomy with an immediate free transverse rectus abdominis musculocutaneous (TRAM) flap reconstruction. Axillary nodal metastases were found in 35 percent of clinically node-negative breast cancer patients. Multivariate analysis showed that patient age of 50 years or younger (p = 0.019), T2 tumor stage or greater (p = 0.031), and presence of lymphovascular invasion on the initial biopsy specimen (p < 0.001) were independent predictors of axillary metastases in clinically node-negative patients. Based on these results, the authors propose an algorithm for decision making in clinically node-negative breast cancer patients who desire autologous breast reconstruction and sentinel lymph node biopsy. Options for immediate autologous breast reconstruction in patients undergoing mastectomy and axillary sentinel lymph node biopsy that may minimize the risk of vascular damage on reoperation include the use of the internal mammary artery and vein as recipient vessels for a free TRAM flap or a pedicled TRAM flap. If an axillary-based blood supply is used, the authors are considering the use of cadaveric dermis to isolate the pedicle of the flap away from the remaining axillary contents. New developments in breast cancer diagnosis and treatment necessitate a team approach, with increased communication between the breast surgeon and the plastic surgeon in planning surgery for these patients.

Histopathologic Evaluation of a New Dermal Allograft Following Explantation

BACKGROUND Numerous materials have been used to accomplish soft tissue augmentation, but the ideal implant remains elusive. Dermaplant is a recently introduced soft tissue matrix derived from human cadaveric dermis and intended for use in soft tissue reconstruction. This product is U.S. Food and Drug Administration (FDA) approved, but there is a paucity of data regarding its clinical performance. OBJECTIVE To report histopathologic findings of an explanted Dermaplant specimen. METHODS A healthy 52-year-old man underwent repair of postblepharoplasty eyelid retraction and a prominent tear trough defect. At the patient's request the tear trough implant was removed in the seventh postoperative week. Gross and microscopic evaluations were performed. RESULTS Fibroblastic infiltration and new collagen production were demonstrated within the implant and at its periphery. Occasional macrophages and giant cells were also noted around the implant. CONCLUSION In this patient the Dermaplant was well tolerated and supported ingrowth of host tissues. The behavior of this material over the long-term cannot be extrapolated from this study.

GENETIC MATERIAL IS PRESENT IN CADAVERIC DERMIS AND CADAVERIC FASCIA LATA

We determined whether genetic material is present in the commercially processed cadaveric allografts used in sling surgery. We evaluated 16 samples from 2 commercial sources of human allograft, including 8 each of freeze-dried gamma irradiated cadaveric fascia lata and acellular cadaveric dermis. Fresh human rectus fascia and sterile saline served as positive and negative controls, respectively. All samples underwent a standard proteinase K/sodium dodecyl sulfate/phenol extraction technique to isolate DNA. Polymerase chain reaction was done to amplify the retrieved DNA material, spectrophotometry to quantify DNA concentration and agarose gel electrophoresis to determine the size of DNA fragments. Of the 16 samples tested from 2 commercial sources of human allograft fascia 14 (87.5%) contained DNA. Mean DNA concentration plus or minus standard error was 258.3 +/- 80.1 and 272.8 +/- 168.8 microg./gm. tissue for cadaveric fascia lata and cadaveric dermis, respectively. Polymerase chain reaction amplified DNA segments of 2,000 bp from 1 of each of the 8 samples of cadaveric fascia lata and cadaveric dermis. Freeze-dried gamma irradiated cadaveric fascia lata and acellular cadaveric dermis contained intact DNA.

Suburethral Sling Using Cadaveric Dermis as a Treatment for Complicated Stress Urinary Incontinence

Suburethral Sling Using Cadaveric Dermis as a Treatment for Complicated Stress Urinary Incontinence

Suburethral sling using cadaveric dermis as a treatment for complicated stress urinary incontinence

Objective: To report our initial experience with the use of a cadaveric dermal allograft as a suburethral sling material. Methods: Ten patients who underwent a suburethral sling procedure vaginally, either alone or in conjunction with other pelvic reconstructive surgery, were monitored prospectively. Dermal allografts obtained from licensed tissue banks measured 2 × 18 cm. After periurethral tunnels were developed bilaterally, a Pereyra needle was passed from the lateral aspect of a 5-cm suprapubic skin incision through one tunnel into the vagina; 0-Ethibond was placed through the long end of the dermis and was used to pass the sling material up until it appeared through the suprapubic incision. This procedure was repeated on the opposite side, and the sling was adjusted underneath the urethra with appropriate tension. The ends of the dermis were sutured to the rectus fascia. All patients had a chief complaint either of stress incontinence alone or of significant genital prolapse (to the introitus or beyond) with ‘unmasked‘ stress incontinence after the prolapse was reduced. All patients had at least 30° of urethral hypermobility and demonstrable stress incontinence on physical examination. All underwent multichannel urodynamic testing with fluoroscopy preoperatively. The diagnosis of complicated stress incontinence was based on one or more of the following factors: open bladder neck on fluoroscopy, Valsalva leak point pressure less than 60 cm H 2O, maximum urethral closure pressure less than 30 cm H 2O, or demonstrable stress incontinence after reduction of major genital prolapse with the urethra supported in its normal position. Follow-up ranged from 3–8 months. Results: All patients were satisfied with the results of the operation. All were continent at 6 weeks, with minimal to no urethral hypermobility and no demonstrable stress incontinence on physical examination. All have remained dry thus far. The average period of postoperative urinary retention requiring intermittent self-catheterization was 7 days (range, 4–18 days). Conclusions: Dermis seems to be an effective sling material at short-term follow-up for this small group of patients. The quality and consistency of the dermis may prove advantageous over cadaveric fascia, which is at times of poor caliber and variable length. The use of dermis eliminates the need for harvesting the patient’s own fascia, thereby shortening operating time and reducing potential complications related to the donor site. It may be superior to synthetic slings in that dermis, a natural material, is unlikely to pose any erosion risk. Larger prospective studies and long-term data are needed to further evaluate the place of cadaveric dermis in incontinence surgery.

Development and Characterization of a Tissue-engineered Human Oral Mucosa Equivalent Produced in a Serum-free Culture System

A problem maxillofacial surgeons face is a lack of sufficient autogenous oral mucosa for reconstruction of the oral cavity. Split-thickness or oral mucosa grafts require more than one surgical procedure and can result in donor site morbidity. Skin has disadvantages of adnexal structures and a different keratinization pattern than oral mucosa. In this study, we successfully assembled, ex vivo, a human oral mucosa equivalent, consisting of epidermal and dermal components, in a defined, essential-fatty-acid-deficient, serum-free culture medium without a feeder layer, that could be used for intra-oral grafting in humans. Autogenous oral keratinocytes were seeded onto a cadaveric dermis, AlloDerm. The oral mucosa equivalent was cultured at an air-liquid interface for 2 wks. The resulting equivalent had a well-stratified parakeratinized epithelial layer similar to native oral keratinized mucosa. Expression of differentiation markers, filaggrin and cytokeratin 10/13, suggested a premature keratinized state. The presence of proliferation markers, proliferating cell nuclear antigen (PCNA) and Ki-67, suggested a state of hyperproliferation. Fatty acid composition of the equivalent was similar to that of in vitro cultured oral keratinocytes but differed from the that of in vivo native tissue, showing a lower content of 18:2 and 20:4, and a higher content of 16:1 and 18:1 fatty acids, respectively. The keratinocytes of the equivalent appeared to be in a more active and proliferative state than native keratinized mucosa. The dynamic nature of the cell population on the oral mucosa equivalent may be beneficial for intra-oral grafting procedures and for transfection of the keratinocytes.

Initial experience with processed human cadaveric allograft skin for reconstruction of the corpus cavernosum in repair of distal extrusion of a penile prosthesis

We describe our initial experience with the novel application of processed human cadaveric allograft skin in reconstruction of a damaged corpus cavernosum associated with distal extrusion of a penile prosthesis. The material was evaluated for ease of reconstruction, adequacy of repair, and outcome. Human processed dermis allograft requires no intraoperative harvesting, is technically easy to fashion, and offers adequate tensile strength in the reconstruction of damaged corpora cavernosa. This initial experience with processed human cadaveric dermis in reconstruction of damaged corpora cavernosa is encouraging. Further evaluation to define the long-term efficacy and scope of application of this material in urologic reconstructive procedures is warranted.