Mittendorf's dot

Definition: Mittendorf’s dot, also called the hyaloid body, is the embryologic remnant of the hyaloid artery as it joins the tunica vasculosa lentis.
Incidence/Prevalence: Mittendorf’s dot is present in normal eyes. It may be associated with posterior lenticonus.
Etiology: Mittendorf's dot represents the remains of the anterior end of the hyaloid artery.
Clinical Findings: On ophthalmoscopy Mittendorf’s dot may be visible as a black/gray axial or slightly nasal paraxial dot at the posterior apex of the lens. By slit lamp microscopy, Mittendorf’s dot is white. Attached one may find a thread-like structure, the remains of the anterior end of the hyaloid artery. The fibrous tissue of the fetal vasculature may extend through a gap in the lens and produce a posterior polar cataract. Progression may occur in the latter instance but is otherwise unusual.
Pathology: The hyaloid vascular system regresses usually by about 7 months. In the figure of this very premature infant, the tunical vasculosa lentis surrounds the lens (arrows 1) and is contiguous with the hyaloid vascular system (arrow 2). Notice the glial sheath of the hyaloid artery (arrow 3). Mittendorf's dot is evident as a white opacity on the posterior surface of the lens in an axial location of this adult autopsy eye (arrow 4).
Treatment: No treatment is generally necessary.