2.10\ Keratoprostheses

2.10.1\ Discussion

Keratoprostheses are artificial corneal substitution devices. The Boston keratoprostheses are perhaps the most commonly used and are available in two forms: the type I device is a collar button-shaped

a

device composed of a polymethyl methacrylate (PMMA) front plate and its stem and a PMMA or titanium back plate, while the type II device has an additional anterior nub that allows for through-the- lid implantation (Fig. 2.42). The devices are considered MRI compatible. Complications that can be observed on CT or MRI include inclusion cyst formation and vitreous hemorrhage.

b

Fig. 2.42  Keratoprostheses. Axial CT image (a) shows a Kpro type 1 device on the left and a Kpro type II device on the right. A glaucoma drainage device is also present on

the right side (arrow). Photograph of a Kpro device in situ (b) (Courtesy of Kathryn Colby MD)