Validation procedures for the Hamilton Thorne Integrated Visual Optical System sperm and cell analyzer.

The Hamilton Thorne Integrated Visual Optical System (IVOS) analyzer is a combined internal optical and computer system widely applied to laboratory animals, such as rat, rabbit, and canine, sperm in reproductive toxicology. It measures sperm motility, progressive motility, velocity, motion parameters, and concentration. The system is specially designed to facilitate on-site validation. Digital encoding allows image storage with absolute replay fidelity for later reexamination, enabling on-site validation complying with Good Laboratory Practices. A NIST-certified scale provides the length standard on which validation is based. Sperm typically move in wavy tracks, which must be characterized and validated. Playback of exact sperm tracks allows visual validation of sperm head position, given as Cartesian coordinates, and visual determination of motility from the playback screen. A cursor checks coordinate values, and manual confirmation of sperm motion parameters may be performed directly from the validated coordinates. Agreement to within 0.2% is obtained between manual and IVOS computation. Concentration is determined using a specific DNA stain that enables discrimination between sperm and somatic cell nuclei. The IVOS concentration of sperm nuclei in homogenized rat testis and cauda epididymis has been determined to be within 5% of manual hemacytometer counts of the same homogenate.