Definition : Ophthalmic diagnostic instruments designed for assessing the retinal circulation of the eyes and the visual function behind media opacity; the instruments permit the patient to visualize the leukocytes flowing in the patient's perifoveal retinal capillaries when viewed against a field of pure blue light (blue field entoptic phenomenon). These instruments usually consist of a light source, a lens system, and a light filter; they project a shortwave blue light into the eye to illuminate the retina, centering the light at the fovea in such a way that the patient can view his or her own white blood cells moving in the perifoveal retinal vessels. The patient reports his/her observations regarding the location of the corpuscles (white cells) in the whole field (e.g., number, movement, distribution, and where there are very few corpuscles). Entoptoscopes are used mainly to evaluate macular pathologies and retinal circulation for detection of some disorders (e.g. glaucoma, diabetes) or to predict potential visual function before cataract surgery.
Entry Terms : "Blue Field Entoptoscopes" , "Vascular Entoptoscopes"
UMDC code : 15288