IOLMaster

IOLMaster is a non-contact optical biometer used to measure eye dimensions for intraocular lens (IOL) power calculation in cataract and refractive surgeries. Developed by Carl Zeiss Meditec, the IOLMaster family includes models such as the IOLMaster 500 and the IOLMaster 700. It provides measurements that are critical for selecting the correct IOL power and for planning refractive outcomes after surgery.

Technology and operation: The traditional IOLMaster relied on partial coherence interferometry to measure axial length and keratometry. Newer generations, notably the IOLMaster 700, employ swept-source optical coherence tomography to capture axial length, keratometry, anterior chamber depth, and lens thickness in a single scan. The device is non-contact, uses infrared light, and guides users with automated alignment, fixation targets, and measurement quality indicators. Its measurements are integrated with common IOL power calculation formulas.

Clinical significance: Accurate biometry is essential for achieving desired postoperative refractive results. The IOLMaster is valued for its repeatability, speed, and non-invasive workflow, reducing corneal indentation risks associated with contact methods. It is widely used in preoperative assessment to provide data for formulas such as SRK/T, Haigis, and Barrett Universal II. Limitations include potential measurement challenges in eyes with dense cataracts or unstable fixation, where alternative imaging or biometry methods may be required.

See also: intraocular lens, cataract surgery, ocular biometry, partial coherence interferometry, swept-source OCT.