聴神経鞘腫の形状パラメータ評価法

―高信頼度簡易計測法の提案―

抄録

An international standard has yet to be established for the tumor diameter parameters of vestibular schwannoma. Knowing the tumor diameter parameters is essential for determining tumor ingravescence and making decisions regarding medical treatment. Yet the measurement of and computation methods for vestibular schwannoma differ from doctor to doctor. The tumor diameter parameters for vestibular schwannoma should reflect tumor volume since the treatment chosen for vestibular schwannoma depends on tumor size. It is thus vital to compare tumor diameter parameters with tumor volume. However, few studies have been made that compare tumor diameter parameter with tumor volume, and even fewer investigations have been conducted regarding new diameter parameters. The object of this study was to gain an understanding of the stereoscopic shape of tumors through three-dimensional (3D) reconstruction for the purpose of deriving original shape parameters and construct a pathological diagnosis support system for otolaryngology. MRI images were used for 3D reconstruction and the calculation of tumor volumes, with tumor diameter parameters in three dimensions instead of the generally used two-dimensional form. A comparison was then made of the calculated volumes, previous parameters and proposed parameters according to graph shape and correlation coefficient. The results of the study show that the proposed parameters are the most useful among the tumor diameter parameters for vestibular schwannoma.