Hypothesizing that the implantation of non-articular (heterotopic) chondrocytes might be an alternative approach to support articular cartilage repair, we analyzed joint cartilage defect healing in the rabbit model after implantation of autologous auricle-derived (auricular) chondrocytes. Autologous lapine articular and auricular chondrocytes were cultured for 3 weeks in polyglycolic acid (PGA) scaffolds before being implanted into critical sized osteochondral defects of the rabbit knee femoropatellar groove. Cell-free PGA scaffolds and empty defects served as controls.
View Article and Find Full Text PDFImplantation of non-articular (heterotopic) chondrocyte-based implants might be an alternative approach to articular cartilage repair. This strategy could be helpful in cases in which there are no or too few articular chondrocytes available. Therefore, this study was undertaken to compare joint cartilage defect healing in the minipig model after implantation of heterotopic auricular and orthotopic articular chondrocytes.
View Article and Find Full Text PDFBackground: There are very few studies analyzing the functional und audiological results of tympanoplasty type I using pure perichondrium.
Materials And Methods: Data of 80 randomly selected patients, who had tympanoplasty surgery between 1998 and 2008 with pure perichondrium were evaluated retrospectively. Average postoperative follow-up was 9 months.
Tissue Engineering is an important method for generating cartilage tissue with isolated autologous cells and the support of biomaterials. In contrast to various gel-like biomaterials, human demineralized bone matrix (DBM) guarantees some biomechanical stability for an application in biomechanically loaded regions. The present study combined for the first time the method of seeding chondrocyte-macroaggregates in DBM for the purpose of cartilage tissue engineering.
View Article and Find Full Text PDFThe availability of autologous articular chondrocytes remains a limiting issue in matrix assisted autologous chondrocyte transplantation. Non-articular heterotopic chondrocytes could be an alternative autologous cell source. The aims of this study were to establish heterotopic chondrocyte cocultures to analyze cell-cell compatibilities and to characterize the chondrogenic potential of nasoseptal chondrocytes compared to articular chondrocytes.
View Article and Find Full Text PDFImplantation of tissue-engineered heterotopic cartilage into joint cartilage defects might be an alternative approach to improve articular cartilage repair. Hence, the aim of this study was to characterize and compare the quality of tissue-engineered cartilage produced with heterotopic (auricular, nasoseptal and articular) chondrocytes seeded on polyglycolic acid (PGA) scaffolds in vitro and in vivo using the nude mice xenograft model. PGA scaffolds were seeded with porcine articular, auricular and nasoseptal chondrocytes using a dynamic culturing procedure.
View Article and Find Full Text PDFInjured articular cartilage is limited in its capacity to heal. Autologous chondrocyte transplantation (ACT) is a suitable technique for cartilage repair, but it requires articular cartilage biopsies for sufficient autologous chondrocyte expansion in vitro. Hence, ACT is restricted by donor-site morbidity and autologous articular chondrocytes availability.
View Article and Find Full Text PDFThe ideal treatment in severe obstructive allergic rhinitis unresponsive to standard therapy is lacking. This study aimed to evaluate the efficacy of endonasal corrective laser surgery in perennial (pAR) and seasonal (sAR) allergic rhinitis. Forty subjects (20 pAR, 20 sAR) underwent videoendoscopic diode laser surgery.
View Article and Find Full Text PDFFor decades, reconstructive surgery of the auricle has presented a challenge to surgeons. An immense number of publications now document the efforts to develop and improve techniques designed to provide reasonable shape and functionality. Since the early 1990s, tissue engineering has become increasingly popular in the field of reconstructive surgery.
View Article and Find Full Text PDFCartilage injury remains a challenge in orthopedic surgery as articular cartilage only has a limited capacity for intrinsic healing. Autologous chondrocyte transplantation (ACT) is a suitable technique for cartilage repair, but requires articular cartilage biopsies for autologous chondrocyte expansion. The use of heterotopic chondrocytes derived from non-articular cartilage sources such as auricular chondrocytes may be a novel approach for ACT.
View Article and Find Full Text PDFIntroduction: The standard treatment of persistent eardrum perforation is conventional surgical closure using myringoplasty or a tympanoplasty type I. In this study the valence of a modified, CO(2)-laser-assisted de-epithelialization of perforation margins was investigated.
Material And Methods: A total of 44 patients with mesotympanal eardrum perforation (diameter 1-5 mm) were included in a partially retrospective and partially prospective study.
A long-lasting dysfunction of the eustachian tube seems to be the etiologic origin for development of chronic otitis media (COM) with mesotympanic perforation, otitis media with effusion (OME), and chronic atelectasis of the middle ear. Surgical interventions in the middle ear generally treat the sequelae of the tube dysfunction but not the dysfunction itself. This prospective clinical study investigated how far fiber-guided laser ablation of the posterior half of the epipharyngeal tubal ostium led to better middle ear ventilation in the otologic disease patterns mentioned below.
View Article and Find Full Text PDFJ Tissue Eng Regen Med
September 2008
Currently, mesenchymal stem cells (MSCs) are considered as the most eligible cells for skeletal tissue engineering. However, factors such as difficult stimulation and control of differentiation in vivo hamper their clinical use. In contrast, periosteum or periosteum-derived cells (PCs) are routinely clinically applied for bone and cartilage repair.
View Article and Find Full Text PDFPurpose: Adenoid cystic carcinomas are rare tumours. Regional lymphatic spread is rather uncommon. Distant metastases occur in approximately half of all patients.
View Article and Find Full Text PDFReconstruction of long tracheal defects remains an unsolved surgical problem. Tissue engineering of respiratory epithelium is therefore of utmost surgical and scientific interest. Successful cultivation and reproduction of respiratory epithelium in vitro is crucial to seed scaffolds of various biomaterials with functionally active respiratory mucosa.
View Article and Find Full Text PDFCholesteatoma is a destructive ear condition requiring complete surgical removal. One major problem lies in the frequent occurrence of residual cholesteatoma caused by squamous epithelium remaining in the middle ear. Our aim is to develop a laser treatment that is selectively directed against residual cholesteatoma cells and can be performed after cholesteatoma surgery in the same session.
View Article and Find Full Text PDFCartilage tissue engineering holds considerable promise for orthopaedic and reconstructive head and neck surgery. With an increasingly ageing population, the number of patients affected by arthritis and recurrent joint pain is constantly growing, along with the associated socio-economic costs. In head and neck surgery reconstructive procedures gain increasing importance in multimodal tumour therapies.
View Article and Find Full Text PDFObjectives: Intratympanic administration of a cell-permeable JNK ligand has been shown to prevent hearing loss after acute acoustic trauma in animal models.
Conclusions: Functional and morphological analysis of the treated ears revealed that AM-111 had an excellent otoprotective effect, even when administered hours after the noise exposure. Blocking the signal pathway with D-JNKI-1 is therefore a promising way to protect the morphological integrity and physiological function of the inner ear in various conditions involving acute sensorineural hearing loss.
Seborrheic keratosis is one of the most common benign neoplasms seen at the trunk, extremities, head and neck of older individuals which rarely occurs in the auditory canal. Even rarer is the occurrence of an inverted or hyperkeratotic variant in this localization. We present the clinical picture of a 74-year-old man with a recurrent hyperkeratotic, partially inverted seborrheic keratosis of the right external auditory canal.
View Article and Find Full Text PDFCartilage tissue engineering is applied clinically to cover and regenerate articular cartilage defects. In this study autologous human cartilage tissue engineering grafts based on bioresorbable polyglactin/polydioxanone scaffolds were analyzed on the broad molecular level. RNA from freshly isolated, primary and expanded adult articular chondrocytes and from three-dimensional cartilage grafts were used for gene expression profiling using oligonucleotide microarrays.
View Article and Find Full Text PDFCultivation of phenotypically stable auricular chondrocytes will have applications in autologous chondrocyte transplantation and reconstructive surgery of cartilage. Chondrocytes grown in monolayer culture rapidly dedifferentiate assuming a fibroblast-like morphology and lose their cartilage-specific pattern of gene expression. Three-dimensional high-density culture models mimic more closely the in vivo conditions of cartilage.
View Article and Find Full Text PDFThe first symptom of an acoustic neuroma in about 50% of the patients is hearing loss, which occurs suddenly in about 5-10% of cases. Acute progressive hearing loss is associated with a broad spectrum of differential diagnoses. Cerebellar and hepatic metastases from a bronchial carcinoma were previously diagnosed in the case presented here, and the most probable causes of the progressive hearing loss, e.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
July 2005
The loss of cartilage and bone because of congential defects, trauma and after tumor resection is a major clinical problem in head and neck surgery. The most prevalent methods of tissue repair are through autologous grafting or using implants. Tissue engineering applies the principles of engineering and life sciences in order to create bioartificial cartilage and bone.
View Article and Find Full Text PDFThe purpose of the study was to examine the morphology and biomechanical characteristics of in vivo cultured tissue-engineered human septal cartilage as a prospective autogenous transplant material for subcutaneous implantation in reconstructive procedures. Chondrocytes were enzymatically isolated from human septal cartilage biopsies. The cell number was expanded in monolayer culture.
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