Abstract
Purpose :
About 20 patients develop ocular complications per 1 million smallpox immunizations, usually through autoinoculation, in which the patient transfers Vaccinia from the immunization site to the eye. We observed central corneal steepening (CCS) that occurred in the setting of Vaccinia virus-associated nummular keratitis.
Methods :
A 40-year-old healthy male with no significant past ocular or medical history who was vaccinated against smallpox in 2003 was examined. Within 2 weeks of vaccination, he developed a diffuse skin rash and bilateral eye redness. He later experienced progressive decline in his corrected distance visual acuity. After undergoing an eye exam, he was informed that the blurry vision was associated with smallpox vaccination. He also developed significant nearsightedness and astigmatism.
Results :
Recently, his vision with corrective glasses of OD=-6.50- 2.50 x 140; 20/30, and -5.00- 2.50 x 130; 20/60. Pupils, ocular motility, confrontation visual field, external exam, lids, and conjunctiva were unremarkable. There were no symblepharon, tear film, or function abnormalities. Bilateral, fine peripheral corneal neovascularization and multiple peripheral coin shape opacities (subepithelial/anterior stroma) that spared the central corneas were noted. Some of these opacities coalesced. Pentacam tomography revealed significant CCS similar to central keratoconus in each eye (Fig. 1). Anterior segment optical coherence tomography demonstrated subepithelial and anterior stromal lesions that were confined to superficial peripheral corneal layers without involvement of deeper corneal layers and the visual axis (Fig. 2). A plausible explanation for the patient’s stable myopic shift and astigmatism is that inflammation caused structural changes in the corneal mid-periphery. This process may be similar to the myopic refractive changes seen in conductive keratoplasty, in which heat-induced shrinking of peripheral collagen lamellae causes CCS.
Conclusions :
Significant CCS can occur in the setting of mid-peripheral nummular keratitis, which presumably mimics the conductive keratoplasty biomechanical changes in the corneal mid-periphery that led to the CCS.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.