Structure of the Ventilation Tube / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Ventilation tube is a percutaneous prosthesis which is exposed to external stimuli. The duration of retention and complication rate of ventilation tube partly depends on which type of tube is used. The purpose of this study is to classify ventilation tubes according to biofunctional characteristics and to design new ventilation tubes experimentally using computer graphics. MATERIALS AND METHOD:Two hundred and forty seven ventilation tubes were classified according to shape, size and material. Experimental design of a ventilation tube was performed with various graphic modellings. RESULTS: Grommet style was most common and most of flanges showed round type. Polymer has been a material of choice in making ventilation tubes. Length of the shaft ranged 1.5mm-15mm. Four kinds of models were created for designing a ventilation tube using computer graphics. CONCLUSION: Biofunctionality should be taken into account in designing ventilation tubes.

Ultrastructure of Temporalis Muscle Fascia Used as Molded Ear Drum Graft / 대한이비인후과학회지

Molded tympanic graft is beneficial in the difficult cases of middle ear surgery, for instance, total perforation of ear drum or revision surgery. For producing molded graft, it is essential to treat the graft material with physico-chemical methods. However, morphological change by influence to the epithelial migration by treatment of graft have not been clarified. To evaluate the morphological effects of molding process on the graft, human temporalis muscle fascias were taken and molded through drying, heating or treatment with chemical preservatives. Their ultrastructures were also evaluated using scanning electron microscope. In molding process, drying of fascia produced widening of interfiber space as well as flattening and fusion of fibers. Heating of fascia produced crater-like defects with amorphous matrix. Formaldehyde preservation induced more remarkable changes of fascia than alcohol.