BACKGROUND AND OBJECTIVES: Raman spectroscopy is a vibrational spectroscopic technique capable of providing details on the chemical composition, molecular structure and molecular interactions in cells and tissues. Its application of distinguishing normal and cancer tissue has been studied in a variety of sites, such as the cervix, lung, larynx and skin. The purpose was to explore spectral changes between normal and cancer tissue in the larynx using Raman spectroscopy to assess the feasibility of using Raman spectroscopy for the early diagnosis of laryngeal cancer. MATERIALS AND METHOD: Laryngeal tissue specimens (13 adjacent normal and 13 cancer tissues) were obtained from patients who underwent total laryngetomy or supracricoid laryngectomy with squamous cell carcinoma of the larynx. The specimens were stored -70 degrees C until use. These specimens were defrosted at room temperature. The Raman spectra from laryngeal tissue specimens could be obtained at 300 mW and 250 scan during 15 minutes of the signal acquisition time using FT-Raman spectroscopy (Bruker Co., Karsruhe, Germany). RESULTS: Raman spectra were different significantly between cancer and adjacent normal tissues of the larynx at 1446 cm-1, 1240 cm-1, 1335 cm-1, and 1655 cm-1 (p=0.007, 0.2, 0.2, 0.3, respectively). The difference of 1446 cm-1 means the change of CH2 bending mode in protein and lipid of malignant tissue. The change of 1335 cm-1 means a decrease in CH3CH2 to a wagging mode of collagen and polynucleotide chain of malignant tissue. The difference of 1240 and 1655 means a decrease in the alpha-helix conformation of collagen. CONCLUSION: This study demonstrates the differences of Raman units between laryngeal cancer and adjacent normal tissue using Raman spectroscopy. In future, Raman spectroscopy may become a useful tool of guided biopsy for accurate pathologic diagnosis and assessment of the adequacy of resection margins.
Biopsy ; Carcinoma, Squamous Cell ; Cervix Uteri ; Collagen ; Diagnosis ; Early Diagnosis ; Female ; Humans ; Laryngeal Neoplasms ; Laryngectomy ; Larynx* ; Lung ; Molecular Structure ; Skin ; Spectrum Analysis ; Spectrum Analysis, Raman*

BACKGROUND AND OBJECTIVES: Although the necessity of hearing aids as one of the rehabilitation methods is increasing, many hearing impaired persons are avoiding the use of behind-the-ear (BTE) hearing aids and prefer the complete-in-the-canal (CIC) hearing aids. CIC hearing aids have cosmetic and acoustic advantages but have problems of acoustic feedback and discomfort in wearing. Changes in the external auditory canal (EAC) by mandibular movements are a primary factor for the acoustic feedback and discomfort. The purpose of this research is to study the pattern of changes in the EAC by mandibular movement using the Korean population as subjects and to get basic data concerning the manufacture of impressions and shells for CIC hearing aids. MATERIALS AND METHODS: Subjects were 19 men with a fit external ear diameter to make CIC hearing aid. Impressions were made by taking 5 different conditions of jaw into consideration : fully opened state, 1/2 opened state, biting state, chewing state and resting state. Impressions were scanned at intervals of O.1mm using a 3D Laser digitizing system. We measured anterior to posterior (AP) width and superior to inferior (SI) height of each impression at the first bend, interbend and the 2nd bend of 5 conditions. RESULTS: Compared with the resting state, statistically significant changes in the AP width of the ear canal were observed at the interbend in the following order : fully opened jaw, 1/2 opened jaw (p <0.05), at 1st bend: 1/2 opened jaw (p<0.05). The 2nd bend biting state showed maximal AP width of the ear canal (p<0.05). The SI height of ear canal revealed statistically insignificant changes. CONCLUSION: We recommend making of ear impressions in the chewing state and shells to be supported at the interbend of the ear canal. The SI dimension of a shell tip should be more ground than AP dimension.
Acoustics ; Ear Canal* ; Ear* ; Ear, External ; Hearing Aids ; Humans ; Jaw ; Male ; Mandible ; Mastication ; Persons With Hearing Impairments ; Rehabilitation