A rare condition in which there remain some parts of the hyaloid artery. Posteriorly there may be a vascular loop or the thread of an obliterated vessel running forward from the optic disc and floating freely in the vitreous. Anteriorly there may be some fibrous remnants attached to the posterior lens capsule and others sometimes floating in the vitreous. The anterior attachment of the hyaloid artery to the lens may also remain throughout life as a black dot, called Mittendorf's dot, and can be seen within the pupil by direct ophthalmoscopy (it appears as a white dot with the biomicroscope). There is rarely any visual interference although patients may sometimes report seeing muscae volitantes. Syn. persistent hyaloid artery. See hyaloid canal; Bergmeister's papilla; pseudopapilloedema; persistent hyperplastic primary vitreous.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann