thumb|Misshapen pupil due to Iritis-caused synechia in the left eye
Ocular synechia is an eye condition where the iris adheres to either the cornea (i.e. anterior synechia) or lens (i.e. posterior synechia). Synechiae can be caused by ocular trauma, iritis or iridocyclitis and may lead to certain types of glaucoma. It is sometimes visible on careful examination but usually more easily through an ophthalmoscope or slit-lamp.
Anterior synechia causes closed angle glaucoma, which means that the iris closes the drainage way of aqueous humour which in turn raises the intraocular pressure. Posterior synechia can be observed in cases of anterior uveitis secondary to severe to moderate bacterial keratitis.