Correction of lower lid retraction combined with entropion using an ear cartilage graft in the anophthalmic socket. (1/47)

PURPOSE: To investigate the surgical results of an ear cartilage graft and supplemental procedures for correcting lower lid retraction combined with entropion in anophthalmic patients. METHODS: We reviewed retrospectively the medical records of 7 anophthalmic patients with lower lid retraction and entropion, who received a posterior lamellar ear cartilage graft and one or both of lateral tarsal strip or eyelash-everting procedure between March 1998 and March 2003. Preoperative and postoperative lid and socket statuses were also investigated. RESULTS: Ear cartilage grafts were performed in all 7 patients, lateral tarsal strips in 6, and eyelash-everting procedures in 5. Postoperative follow-up durations ranged from 4 to 28 months (average 12.6 months). Retractions were corrected during follow-up in all patients. There were no cases of entropion immediately after surgery. However, the eyelashes of the lower lid returned to an upright position in 4 patients, but not so severe as to touch the ocular prosthesis, and thus did not require surgical correction during follow up. CONCLUSIONS: Lower lid retraction combined with entropion in anophthalmic patients can be corrected effectively using an ear cartilage graft with selective, supplemental procedures.  (+info)

Mice expressing HLA-DQ6alpha8beta transgenes develop polychondritis spontaneously. (2/47)

Relapsing polychondritis (RP) is a human autoimmune disease of unknown etiology in which cartilaginous sites are destroyed by cyclic inflammatory episodes beginning, most commonly, during the fourth or fifth decade of life. We have previously described collagen-induced polychondritis that closely mirrors RP occurring in young (6-8 weeks old) HLA-DQ6alphabeta 8alphabeta transgenic Abeta0 mice, following immunization with heterologous type II collagen (CII). We present evidence here that transgenic strains expressing the DQ6alpha8beta transgene develop spontaneous polychondritis (SP) at the mouse equivalent of human middle age (4.5-6 months and 40-50 years old, respectively) and display polyarthritis, auricular chondritis and nasal chondritis--three of the most common sites affected in RP. Auricular chondritis in SP, like RP but unlike CII-induced polychondritis, exhibited a relapsing/remitting phenotype, requiring several inflammatory cycles before the cartilage is destroyed. Elevated serum levels of total IgG corresponded with the onset of disease in SP, as in RP and CII-induced polychondritis. No CII-specific immune response was detected in SP, however--more closely mirroring RP, in which as few as 30% of RP patients have been reported to have CII-specific IgG. CII-induced polychondritis displays a strong CII-specific immune response. SP also demonstrated a strong female preponderance, as some workers have reported in RP but has not observed in CII-induced polychondritis. These characteristics of SP allow for the examination of the immunopathogenesis of polychondritis in the absence of an overwhelming CII-specific immune response and the strong adjuvant-induced immunostimulatory influence in CII-induced polychondritis. This spontaneous model of polychondritis provides a new and unique tool to investigate both the initiatory events as well as the immunopathogenic mechanisms occurring at cartilaginous sites during the cyclic inflammatory assaults of polychondritis.  (+info)

Comparison of butyl-2-cyanoacrylate, gelatin-resorcin-formaldehyde (GRF) compound and suture in stabilization of cartilage grafts in rabbits. (3/47)

Cartilage grafting is an interesting option for rhinoplasties refinements. AIM: To compare butyl-2-cyanoacrylate, compound gelatin-resorcin-formaldehyde (GRF) and suture control to determine the efficacy of these tissue glue preparations in securing grafted cartilage. STUDY DESIGN: Experimental. METHODS: Fifteen male adult New Zealand rabbits were submitted to a surgical procedure to harvest 6 auricular cartilage grafts from each animal. 2 of these grafts in each animal were glued together with butyl-2-cyanoacrylate, 2 with compound gelatin-resorcin-formaldehyde and 2 sewn together with nylon suture. These sandwich grafts were then glued or sewn to the periosteum of the calvaria. After 2, 6 and 12 weeks, groups of 5 animals were sacrificed and histological analysis for inflammation was performed. Cartilage graft migration, adhesion and deformities of the grafts were also evaluated. RESULTS: There was less migration of the cartilages glued with GRF than with cyanoacrylate and suture. There was no statistical difference between the 3 materials of graft stabilization in relation to the inflammatory reaction in all evaluated periods. There wasn't detachment neither deformity in the cartilage sandwiches sewn with suture. The majority of detachment and deformed cartilages were found among those glued with cyanoacrylate. The number of deformed cartilages was directly related to the number of detached cartilages. The data were statistically significant (p< 0.05). CONCLUSION: The compound gelatin-resorcin-formaldehyde revealed to be a stabilization material for cartilage grafts in rabbits better than butyl-2-cyanoacrylate. The compound gelatin-resorcin-formaldehyde was also better than the suture when comparing its fixation to the periosteum.  (+info)

Effects of auricular chondrocyte expansion on neocartilage formation in photocrosslinked hyaluronic acid networks. (4/47)

The overall objective of this study was to examine the effects of in vitro expansion on neocartilage formation by auricular chondrocytes photoencapsulated in a hyaluronic acid (HA) hydrogel as a next step toward the clinical application of tissue engineering therapies for treatment of damaged cartilage. Swine auricular chondrocytes were encapsulated either directly after isolation (p = 0), or after further in vitro expansion ( p = 1 and p = 2) in a 2 wt%, 50-kDa HA hydrogel and implanted subcutaneously in the dorsum of nude mice. After 12 weeks, constructs were explanted for mechanical testing and biochemical and immunohistochemical analysis and compared to controls of HA gels alone and native cartilage. The compressive equilibrium moduli of the p = 0 and p = 1 constructs (51.2 +/- 8.0 and 72.5 +/- 35.2 kPa, respectively) were greater than the p = 2 constructs (26.8 +/- 14.9 kPa) and the control HA gel alone (12.3 +/- 1.3 kPa) and comparable to auricular cartilage (35.1 +/- 12.2 kPa). Biochemical analysis showed a general decrease in glycosaminoglycan (GAG), collagen, and elastin content with chondrocyte passage, though no significant differences were found between the p = 0 and p = 1 constructs for any of the analyses. Histological staining showed intense and uniform staining for aggrecan, as well as greater type II collagen versus type I collagen staining in all constructs. Overall, this study illustrates that constructs with the p = 0 and p = 1 auricular chondrocytes produced neocartilage tissue that resembled native auricular cartilage after 12 weeks in vivo. However, these results indicate that further expansion of the chondrocytes (p = 2) can lead to compromised tissue properties.  (+info)

Expression of actin isoforms in human auricular cartilage. (5/47)

The objective of this study was to determine whether human auricular chondrocytes can also express alpha-- -smooth muscle actin. Immunohistochemistry using monoclonal antibodies for alpha-smooth actin, muscle-specific actin, beta-actin, S-100 protein, CD34, and desmin was performed on samples of human ear cartilage obtained from 20 individuals during a partial resection of the ear for different reasons. Moreover, the RT-PCR analysis of actin isoforms in auricular chondrocytes was performed. Approximately 60 % of the chondrocytes of the ear cartilage expressed alpha-smooth muscle actin as demonstrated by immunohistochemistry in all the examined samples. Actin-positive chondrocytes occurred in both external subperichondrial layers of the auricular cartilage. This finding was confirmed by the RT-PCR technique. The knowledge of this fact could help us to better understand the chondrocyte changes occurring during the healing and transplantation of auricular cartilage. The question of whether it is necessary to refer to these predominating cells in ear cartilage as myochondrocytes is considered. This is the first report of an unusual immunophenotype and contractile potential for human auricular chondrocytes.  (+info)

Comparison of microtia reconstructive surgery with autograft versus homograft. (6/47)

BACKGROUND: Microtia is a congenital abnormality with low incidence but considerable morbidities. Reconstruction of the microtia deformity is a complex and difficult process that requires a proper planning. The primary technique of reconstruction employs patient's own rib cartilage. Irradiated homograft cartilages previously have been used in facial reconstruction but its application in microtia surgery has not been reported yet. This study is designed to compare the results of autograft versus homograft auriculoplasty. METHODS: Between 1992 - 2002, 23 patients underwent auricular reconstructive surgery by the senior author in our department. Autograft implantation was performed in one stage but homograft auriculoplasty was done in two stages. RESULTS: Auricular deformity was right-sided in 13, left-sided in 8, and bilateral in 2 cases. Implanted graft was autograft in 9 patients and homograft in 14 patients. During mean follow-up of 4 years, cartilage graft resorption was detected in two cases, one in autograft and one in homograft group (P > 0.05). No postoperative infection was observed. Status of postauricular sulcus was optimal in 85.7% of homograft and 77.8% of autograft groups (P > 0.05). The satisfaction score of the patients and/or parents was excellent in 66.7% of autograft and 92.9% of homograft groups (P < 0.01). CONCLUSION: Based on better satisfaction score, equivalent aesthetic appearance, and absence of complications such as scaring and pain on the chest wall, homograft auriculoplasty is an appropriate option for reconstructive surgery in patients with microtia.  (+info)

Cartilage tissue engineering for laryngotracheal reconstruction: comparison of chondrocytes from three anatomic locations in the rabbit. (7/47)

Tissue engineering may provide a technique to generate cartilage grafts for laryngotracheal reconstruction in children. The present study used a rabbit model to characterize cartilage generated by a candidate tissue engineering approach to determine, under baseline conditions, which chondrocytes in the rabbit produce tissue-engineered cartilage suitable for in vivo testing in laryngotracheal reconstruction. We characterized tissue-engineered cartilage generated in perfused bioreactor chambers from three sources of rabbit chondrocytes: articular, auricular, and nasal cartilage. Biomechanical testing and histological, immunohistochemical, and biochemical assays were performed to determine equilibrium unconfined compression (Young's) modulus, and biochemical composition and structure. We found that cartilage samples generated from articular or nasal chondrocytes lacked the mechanical integrity and stiffness necessary for completion of the biomechanical testing, but five of six auricular samples completed the biomechanical testing (moduli of 210 +/- 93 kPa in two samples at 3 weeks and 100 +/- 65 kPa in three samples at 6 weeks). Auricular samples showed more consistent staining for proteoglycans and collagen II and had significantly higher glycosaminoglycan (GAG) content and concentration and higher collagen content than articular or nasal samples. In addition, the delayed gadolinium enhanced MRI of cartilage (dGEMRIC) method revealed variations in GAG spatial distribution in auricular samples that were not present in articular or nasal samples. The results indicate that, for the candidate tissue engineering approach under baseline conditions, only rabbit auricular chondrocytes produce tissue-engineered cartilage suitable for in vivo testing in laryngotracheal reconstruction. The results also suggest that this and similar tissue engineering approaches must be optimized for each potential source of chondrocytes.  (+info)

Histopathology of ossicular grafts and implants in chronic otitis media. (8/47)

OBJECTIVES: We describe the histopathology of ossicular grafts and implants so as to provide insight into factors that may influence functional results after surgery for chronic otitis media. METHODS: Histopathologic observations were made on 56 cases: 50 surgical specimens and 6 temporal bone cases in which the graft was sectioned in situ. RESULTS AND CONCLUSIONS: Autogenous malleus, incus, and cortical bone grafts behaved in a similar manner and maintained their morphological size, shape, and contour for extended periods of time, at least up to 30 years. These histopathologic observations support the continued use of autograft ossicular and cortical bone grafts for middle ear reconstruction. Cartilage grafts developed chondromalacia with resulting loss of stiffness and showed a tendency to undergo resorption. Synthetic prostheses made of porous plastic (Plastipore, Polycel) elicited foreign body giant cell reactions with various degrees of biodegradation of the implants. Prostheses made of hydroxyapatite and Bioglass were enveloped by a lining of connective tissue and mucosal epithelium. The Bioglass material was broken down into small fragments and partially resorbed by a host response within the middle ear. These results warrant caution in the use of prostheses made of porous plastic or Bioglass.  (+info)