The OPTICAL BIOMETER AL-Scan is a measuring device that can measure as a single
The OPTICAL BIOMETER AL-Scan is a measuring device that can measure as a single unit the values necessary to calculate the power of an IOL for cataract surgery such as axial length, corneal curvature radius, and anterior chamber depth. It measures these necessary values successively through a non-contact optical measurement method. An optional A-scan probe is also available to scan axial length with an ultrasonic measurement functionby touching it to the cornea should optical measurement not be successful. In addition, an anterior eye segment image overlaid with the corneal meridians can be created as a reference for toric IOL implantation. The AL-Scan also has the function to calculate the power of an IOL using measured values such asaxial length.
The NIDEK US-500 Echoscan is an ultrasonic device to measure the axial length an
The NIDEK US-500 Echoscan is an ultrasonic device to measure the axial length and corneal thickness and provide the information to be used for diagnosis.Axial length is one of the parameters used to determine the refractive power of an IOL prior to cataract surgery. By inputting the measured axial length with other parameters, the refractive power of an IOL can be calculated. Corneal thickness is a necessary parameter when considering the clinical influence of surgery, drugs and contact lenses upon endothelium tissue. Pachymetry is now commonly performed prior to and after corneal refractive surgery using devices such as the excimer laser. The US-500 is comprised of a touch screen, main body with a built-in printer, Pachymetry probe, and foot switch.
Ultrasonic waves are the sound waves pitched above the range of human hearing wh
Ultrasonic waves are the sound waves pitched above the range of human hearing whose frequency is 20,000 Hz or more. In the medical field, ultrasonic waves of frequencies between 1 and 15 MHz are applied, and these types of high sound waves have the following characteristics similar to light:They have a high tendency to travel in a straight direction. They have characteristics such as reflect.