Posterior keratoconus.

Posterior keratoconus (PKC) is a rare, typically non-inflammatory condition that is characterised by an abnormal posterior corneal curvature, which may be accompanied by overlying stromal opacification. It is usually congenital and can be associated with other ocular and systemic abnormalities. PKC remains a clinical diagnosis, although imaging techniques including ultrasound biomicroscopy and anterior segment optical coherence tomography may be useful tools for confirmation and classification. Genetic studies should be considered, although no specific genetic defects have been identified thus far. As a potential cause of amblyopia, early diagnosis and management are crucial in maximising visual potential. Occasionally, management considerations may also include surgical intervention, such as corneal transplantation. Intraocular lens power calculation at the time of cataract surgery requires special consideration. Here, we review the present literature on PKC and consider future directions in the management of this rare entity.