Three-dimensional ultrasound. Initial experience in various eye diseases

Background. Studies have confirmed three-dimensional (3-D) ultrasound as a practical diagnostic tool in examining the eye and orbit and suggest its ro utine clinical use. Materials and methods. 3-D ultrasound was prospectively performed in 46 pat ients (46 eyes) with various ocular diseases. In six large choroidal melano mas the tumor volume were measured by 3-D ultrasound and compared to that m easured by MRI and to that calculated by a theoretical formula. To assess t he reproducibility of volumetry by 3-D ultrasound the volumes of such three intraocular tumors were measured ten times using ten different virtual sec tioning planes and a section thickness of 0.5 mm and/or 1.0 mm. Results. 3-D ultrasound allows the precise assessment of complex three-dime nsional structures. Choroidal melanoma volumes measured by 3-D ultrasound, MRI, and theoretical calculation were in the same range. Conclusion. Intraocular tumor volume can be measured well by 3-D ultrasound ,which may be of clinical importance in follow-up examinations.