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Objectives/Hypothesis The objective of this study was to compare the viability of cartilage grafts embedded in platelet-rich fibrin matrix (PRFM) wrapped with no material (bare diced cartilage grafts), oxidized methylcellulose (Surgicel), or acellular dermal tissue (AlloDerm). Study Design Experimental study. Methods In this study, six New Zealand rabbits were used. Cartilage grafts including perichondrium were excised from each ear and diced into 2-mm-by 2-mm pieces. There were four comparison groups: 1) group A, diced cartilage (not wrapped with any material); 2) group B, diced cartilage wrapped with AlloDerm; 3) group C, diced cartilage grafts wrapped with Surgicel; and 4) group D, diced cartilage wrapped with PRFM. Four cartilage grafts were implanted under the skin at the back of each rabbit. All rabbits were sacrificed at the end of 10 weeks. The cartilages were stained with hematoxylin-eosin, Masson's Trichrome, and Orcein. After that, they were evaluated for the viability of chondrocytes, collagen content, fibrillar structure of matrix, and changes in peripheral tissues. Results When the viability of chondrocytes, the content of fiber in matrix, and changes in peripheral tissues were compared, the cartilage embedded in the PRFM group was statistically significantly higher than in the other groups ( P < 0.05). Conclusion We concluded that PRFM has significant advantages in ensuring the chondrocyte viability of diced cartilage grafts. It is also biocompatible, with relatively lesser inflammation and fibrosis. Level of Evidence N/A. Laryngoscope, 125:E104-E111, 2015 [ABSTRACT FROM AUTHOR]

Objective: Micronized Dermis (MD) has been used for injection laryngoplasty for correction of glottic insufficiency since 2000. There is controversy whether the material is temporary or permanent. This is a retrospective review of 381 injections in 344 patients. From this review, we hope to better define the role of MD in injection laryngoplasty. Method: Retrospective chart review from a single surgeon (2000-2010) Results: The indications for MD were for both temporary and permanent correction of glottic insufficiency. The diagnoses were: vocal fold paralysis (n = 216), scar (n = 51), atrophy (n = 42), sulcus (n = 22), and others (n = 13). The material has the best effect when placed into the membranous vocal fold just lateral to the vocal ligament. The operative and postoperative complication was 1.05%. Twenty-nine percent of all injections resulted in unwanted absorption. Overinjection was needed and transcervical approach was preferred to prevent implant extrusion with over-injection. The median volume of injected material has increased from 0.8 cc to 1.0 cc over the decade. In 159 patients with long-term follow-up (>1 year), there was a 14% incidence of reinjection. Despite this, the overall need for open procedures in patients with long-term follow-up was 20%. Conclusions: Despite the problems of inconsistency in preparation, slow absorption and need for overinjection, micronized dermis is a safe allograft material that has long-term (>1 year) stability. The material may reduce the need for open surgery. It can be used for both temporary and permanent vocal fold augmentation. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis: AlloDerm (LifeCell Corp., Branchburg, NJ) is commonly employed for reconstruction of ablative soft tissue and mucosal defects following surgical resections. Although devoid of growth factors, AlloDerm may serve as an adhesive matrix for binding of growth factors, increasing local angiogenesis, and wound healing. We hypothesized that AlloDerm would enhance angiogenesis and might be altered with autologous blood products to enhance initiation of the angiogenic response. Methods: We used a human placental vein in a fibrin-thrombin clot-based angiogenesis model. Four groups, human placental vein (HPVM), HPVM with AlloDerm, HPVM with AlloDerm plus platelet-poor plasma, and HPVM with AlloDerm plus platelet-rich plasma were evaluated. Endothelial cell growth was evaluated visually (40×). Hematoxylin and eosin staining and immunofluorescent staining for growth within the AlloDerm matrix were also performed. To assess human umbilical vein endothelial cell (HUVEC) sites of attachment to AlloDerm, we incubated HUVEC cells with AlloDerm for a period of 2 weeks and evaluated attachment with anti-factor VIII immunofluorescence. Results: Angiogenic initiation decreased in the combined placental vein with AlloDerm group ( P < .0001 at day 7, 14, 21). Additionally, initiation in the AlloDerm plus platelet-poor plasma group was significantly better than the AlloDerm alone group when placentas 2 and 3 were compared ( P < .0001). On hematoxylin and eosin staining and immunofluorescent factor VIII staining, no endothelial growth into the AlloDerm was noted in the samples analyzed. Conclusions: AlloDerm may be enriched with platelet-poor plasma to stimulate greater initiation and wound healing; however, AlloDerm inhibits angiogenic initiation in this model. Laryngoscope, 2010 [ABSTRACT FROM AUTHOR]

Objective To report our experience in reconstructing defects of the anterior and middle cranial fossa skull base using endoscopic placement of acellular dermal allograft (AlloDerm, LifeCell Corp., The Woodlands, TX). Study Design Retrospective chart review. Methods In all cases, the skull base repair was completed with a similar technique. After identification of the defect boundaries, endoscopic transnasal repair was performed through placement of a layered reconstruction of acellular dermal allograft, septal bone/cartilage, and acellular dermal allograft, which were all placed on the intracranial side of the defect. A mucosal free graft was draped over the reconstruction. Fibrin glue was used to hold the mucosal graft in place, and the reconstruction was supported by both absorbable and nonabsorbable nasal packing. Results Eight patients with nine skull base defects underwent the procedure for repair of cerebrospinal fluid rhinorrhea. All defects were successfully repaired. One patient underwent successful reconstruction of bilateral ethmoid roof defects that resulted from endoscopic resection of ethmoid adenocarcinoma. Twenty-four patients underwent primary resection of hypophyseal adenomas. Twenty-three patients had macroadenomas, and intraoperative cerebrospinal fluid leaks were noted in 11 patients. Sellar repairs after trans-sphenoidal hypophysectomy were successful in 22 of 24 patients. One patient with hypophysectomy required reoperation (1 of 24 [4%]) for secondary closure of a cerebrospinal fluid leak. Serious complications were avoided in all patients. Patients were followed for a period ranging from 5 to 57 months (mean period, 34 mo). Conclusions Acellular dermal allograft can be successfully used for the reconstruction of anterior and middle cranial fossa skull base defects. This allograft, which is easy to manipulate endoscopically, provides an effective seal and barrier in skull base reconstruction and avoids the need for a donor site. [ABSTRACT FROM AUTHOR]

Objectives To evaluate and discuss the role of acellular human dermal matrix (AlloDerm, LifeCell Corp., Branchburg, NJ) graft for coverage of radial forearm free flap donor site. Study Design Prospective, nonrandomized study. Methods Fifty-two consecutive patients underwent harvest of 52 radial forearm fasciocutaneous free flaps. All 52 donor sites were covered by AlloDerm graft. Split-thickness skin graft was not used to reinforce the acellular dermal graft in the series. Clinical phases of healing, duration of healing, and donor site complications were studied. Results No donor site complications except seroma formation in five patients was noted. This was treated by conservative measures. Full range of hand motion was allowed in 3 days. Complete healing occurred within 8 to 12 weeks. Scar contracture after complete healing was minimum in all patients. Range of motion of the hand and fingers during flexion, extension, supination, and pronation was identical on the operated and nonoperated sides. Conclusion AlloDerm graft is a viable alternative to split-thickness skin graft for coverage of the radial forearm free flap donor site. [ABSTRACT FROM AUTHOR]

Objective To report our experience in reconstructing pharyngeal defects that cannot be closed primarily, using acellular dermal matrix (AlloDerm, LifeCell Corp., Branchburg, NJ) and sternocleidomastoid (SCM) muscle flap. Study Design Prospective, nonrandomized, nonblinded study in the setting of an academic tertiary care medical center. Methods Fourteen patients underwent reconstruction of through-and-through defects of partial pharyngectomy for squamous cell carcinoma using AlloDerm graft. Primary closure of the defects was not possible because of substantial loss of pharyngeal tissue. The graft was reinforced with superiorly based SCM muscle flap in 10 patients. The remaining four patients did not receive any flap. Eleven lesions involved the lateral pharyngeal wall, and three were piriform sinus lesions. Patients were followed for a period ranging from 3 to 20 months. Outcome measures were determined on several parameters including graft take rate, evidence of graft contracture, postoperative complications, resumption of diet, intelligibility of speech, and decannulation. All patients were evaluated by a speech pathologist by means of a bedside swallowing examination. Five patients had videofluoroscopic studies. The three patients with piriform sinus lesions underwent videostroboscopic examination to assess vocal cord function. Results There was a high success rate for graft take. Two patients developed postoperative fistulas that resolved with conservative management . One of the 10 patients with SCM flap and one of the 4 patients without SCM flap developed fistulas. Clinically significant graft contracture or pharyngeal stenosis was not observed in any patients. All patients resumed oral intake. Ten patients resumed a normal diet, two tolerated a soft diet, and two could take purees. Decannulation was successful in all patients. Two of the three patients with piriform sinus lesions had vocal cord palsies after surgery resulting in breathy dysphonia. They underwent type I thyroplasty for vocal rehabilitation. All patients had intelligible speech. Conclusions Thick AlloDerm, reinforced with SCM muscle or cervical soft tissue, provides a useful alternative option for reconstruction of pharyngeal defects that cannot be closed primarily. It is safe and effective and provides excellent functional outcomes. [ABSTRACT FROM AUTHOR]

Objectives To assess the use of an acellular dermal allograft in the repair of chronic tympanic membrane perforations. Chronic tympanic membrane perforations are a common problem in otolaryngology, and although surgical tympanoplasty using either temporalis fascia or rice paper has proven to be highly successful, these materials are not without their own limitations. The search has continued for a simpler, yet equally effective, means of repairing persistent tympanic membrane perforations in an office setting. In this study we experimentally evaluated the use of an acellular dermis (AlloDerm, (LifeCell Corporation, The Woodlands, TX) as an alternative to traditional tympanoplasty materials. Study Design Prospective study using 28 adult chinchillas. Methods Subtotal tympanic membrane perforations were created bilaterally in 28 adult chinchillas. Animals with noninfected, stable perforations that showed no signs of epithelial regeneration after 5 to 8 weeks were used to compare the use of rice paper patch with AlloDerm in patch tympanoplasties. Results Eighteen of 23 tympanoplasties (78%) that were performed using AlloDerm showed no signs of perforation after 5 to 6 weeks. In those performed using rice paper control, 14 of 21 (66%) showed no signs of perforation after 5 to 6 weeks. In addition, histological evaluation of the healed tympanic membranes demonstrated that the acellular dermis had been incorporated within the middle fibrous layer of the tympanic membrane. Conclusions The results and histological studies suggest that acellular dermis may be a suitable alternative to traditional materials currently used for patch tympanoplasty. Future studies to evaluate the efficacy of acellular dermis in humans are warranted. [ABSTRACT FROM AUTHOR]

Objective To evaluate the integration of AlloDerm (LifeCell Corp., The Woodlands, TX) in a field exposed to external-beam radiation (EBR) by analyzing graft thickness, fibroblast recellularization, and neovascularization. Study Design Randomized control. Methods Thirty-six male Sprague-Dawley rats (n = 36) were randomly assigned to four groups. One hind leg of each rat was exposed to 20 Gy of EBR; the other limb served as the nonirradiated control. Two weeks after irradiation, AlloDerm was implanted into both hind legs. Grafts were harvested at 3, 4, 6, and 14 weeks after implantation and underwent histological analyses. Results There was no statistically significant difference in graft thickness, fibroblast count, or neovascularization between the grafts placed in the irradiated bed and the controls (n = 33, P = .332, P = .336, and P = .057, respectively). However, at week 3, fibroblast counts in the graft placed in the field exposed to EBR were significantly lower than those of controls ( P = .019), although at week 14 the counts in the experimental limb were higher than those of the controls ( P = .002). Graft thickness ( P = .001) and fibroblast count ( P < .004) were lower at week 14 than at earlier time periods for both the experimental and control grafts. Conclusions In the rat model, graft thickness and neovascularization of the AlloDerm dermal implant do not appear to be adversely affected by a field that has received EBR. Fibroblast ingrowth may be hindered in the early postimplantation period but appears to normalize in the long term. Furthermore, overall graft thickness and fibroblast counts decrease over time, regardless of irradiation status. [ABSTRACT FROM AUTHOR]

Objective/Hypothesis The purpose of this work is to evaluate the performance of an acellular dermal allograft (AlloDerm; LifeCell Corp., The Woodlands, TX) in tympanic membrane (TM) grafting. Study Design A retrospective review of 20 consecutive tympanoplasty surgeries using temporalis fascia and 20 consecutive procedures using AlloDerm. Methods The charts of 20 consecutive adults who underwent tympanoplasty surgery were reviewed to evaluate graft take and hearing results. Similarly, 20 consecutive patients who had TM grafting with AlloDerm were reviewed. Pre- and postoperative air-bone gaps (ABG) at 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz were compared. Results There were no graft failures in either the temporalis fascia group or the AlloDerm group. No statistically significant difference was noted in hearing results when comparing the residual conductive loss in both postoperative groups. Conclusions AlloDerm is a suitable material for TM grafting. This product is especially valuable in revision surgery in which the availability of appropriate autologous grafting material is limited. [ABSTRACT FROM AUTHOR]