Article

Evaluation of pharyngolaryngeal region with 3-D computed tomography

Department of Otolaryngology, Kanazawa Medical University, Daigaku 1-1, Uchinada, Ishikawa 920-0293, Japan; Department of Radiology, Kanazawa Medical University, Daigaku 1-1, Uchinada, Ishikawa 920-0293, Japan
International Congress Series 01/2003; DOI: 10.1016/S0531-5131(03)01623-6

ABSTRACT We present a new method of 3-D CT reconstruction with space extraction (volume rendering) technique in this study. The objective of this study is to demonstrate pharyngeal space with 3-D CT images and evaluate the volume change of upper airway in normal individuals and patients with snoring and sleep apnea. Axial CT scanning was taken before 3-D images of upper airway cavity being reconstructed. Then the volume of airway was measured, in each aspect of inspiration, expiration, sleeping, snoring and apnea. Repeat of closing and widening of airway was clearly demonstrated in OSAS (sleep apnea syndrome) patients during their sleep. It was also found that the volume changes of airway corresponded with shape changes. This new method is expected to be helpful in locating obstructive site and estimating surgical outcome of OSAS.

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