title: Ultrasonographic, three-dimensional scanning for determination of intraocular tumor volume.
abstract: Important prognostic information may be gained from knowing the volume of intraocular tumors, such as choroidal melanomas. To measure such volume, we developed an ultrasonographic 3-D scanning system, which operates by an axial, back and forth, half-turn rotation of a commercial sector scanning transducer, applied directly onto a closed eyelid. Control of movement, data acquisition, and image analysis are accomplished by means of a microcomputer and application-specific software. The elapsed time for scanning and digitizing 11 cross-sectional images across a human eyeball, is 4 sec. Outlines of specific structures are traced manually. The system was tested through repeated, in vitro measurements of known volumes of meat; the mean variation coefficient of these measurements was 2.8%. While accurate estimates were obtained on volumes between 0.01-0.25 ml, these are linearly dependent on gain setting. A patient with a choroidal melanoma was scanned repetitively. The procedures of scanning and tracing contributed about equally to the total variance. This method of scanning allows repeatable, reliable, and easily generated measurements of a tumor's volume and, thus, has great potential for use in the diagnosis and treatment of malignant, intraocular tumors.
authors.affiliation: Department of Ophthalmology, Kommunehospitalet, Aarhus University, Denmark.
authors.forename: P K
authors.initials: PK
authors.lastname: Jensen
authors.forename: M K
authors.initials: MK
authors.lastname: Hansen
mesh_terms: D002830:Choroid Neoplasms / Q000000981:diagnostic imaging*; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008545:Melanoma / Q000000981:diagnostic imaging*; D009367:Neoplasm Staging / Q000295:instrumentation / Q000379:methods; D014463:Ultrasonography / Q000295:instrumentation