Type I Boston keratoprosthesis with cataract extraction and intraocular lens placement for visual rehabilitation of herpes zoster ophthalmicus: the "KPro Triple".

Abstract

Management of corneal scarring following herpes zoster ophthalmicus (HZO) is challenging due to the dense corneal anesthesia that results from viral damage to the subepithelial nerve plexus. These patients have significant risk of graft failure following traditional corneal transplantation. We present a case of a 74-year-old white woman with counting fingers vision from HZO-associated corneal scarring and mature cataract where visual rehabilitation was accomplished with a Type I Boston keratoprosthesis (KPro) and concurrent extracapsular cataract extraction and posterior chamber intraocular lens placement (the "KPro Triple"). One month following surgery, the patient's uncorrected visual acuity improved to 20/25; this level of vision has been maintained for 7 months at present. The keratoprosthesis is assembled by creating a sandwich composed of the KPro front plate, the donor cornea, and the KPro backplate that is secured with a locking ring. The host cornea is then trephined and posterior synechiae lysed to allow access to the mature cataract. The cataract is manually expressed and a posterior chamber intraocular lens implanted. The assembled keratoprosthesis is then sutured into position with 9.0 nylon. A bandage contact lens is placed. In patients with severe neurotrophic keratopathy, traditional penetrating keratoplasty is fraught with problems, including poor epithelial healing and corneal ulceration. The Boston KPro can provide rapid visual rehabilitation, despite corneal anaesthesia in these patients, and is currently our treatment of choice as a primary procedure for HZO patients who need corneal transplantation.