ABSTRACT
OBJECTIVES: To determine the role of the main cartilage components in the internal system of interlocked stresses and to clarify the effect of laser beam irradiation on cartilage. DESIGN: Control and experimental series. SUBJECTS: Rabbit ear cartilage. INTERVENTION: Rabbit ear cartilage strips incubated in collagenase and hyaluronidase enzyme solutions for specific periods were examined, and the observed changes in shape, strength, and elasticity were recorded, as well as the effect of carbon dioxide laser irradiation. Laser-pretreated cartilage strips were also incubated in the enzyme solutions to determine whether the laser-provoked changes were susceptible to enzymatic action. All cartilage pieces were examined by light and electron microscopy. RESULTS: Collagenase-treated cartilage strips gradually lost their interlocked stresses, while hyaluronidase-treated strips mostly maintained their shape and their physical characteristics. Hyaluronidase-incubated cartilage strips altered their shape when they were laser treated. Collagenase-treated cartilages did not modify their shape when they were laser treated. Laser-pretreated cartilage pieces lost their new form in collagenase solutions but kept their laser-evoked shape when put in hyaluronidase solutions. CONCLUSION: The macroscopic observations combined with light and electron microscopy findings argue for the distinct role of the collagen network in morphologic cartilage shape and tensile strength preservation and provide a probable mechanism of cartilage transformation owing to carbon dioxide laser irradiation.
Subject(s)
Collagenases/pharmacology , Ear Cartilage , Hyaluronoglucosaminidase/pharmacology , Lasers , Animals , Collagen/ultrastructure , Ear Cartilage/drug effects , Ear Cartilage/radiation effects , Ear Cartilage/ultrastructure , Extracellular Matrix/drug effects , Extracellular Matrix/radiation effects , Extracellular Matrix/ultrastructure , In Vitro Techniques , Microscopy, Electron, Transmission , RabbitsABSTRACT
Parotid gland is the most common location of malignant mixed tumors. Three different subtypes of these tumors exist: carcinoma ex pleomorphic adenoma, carcinosarcoma, and metastasizing mixed tumor. Carcinoma ex-pleomorphic adenoma is by far the most common subtype. Although unusual sites of these tumors have been published, we report an extremely rare case of a malignant mixed tumor located in the nasal cavity.
