Are iris mammillations correlated with keratoconus?

Abstract

PurposeTo describe the presence of iris mammillations (IM) in keratoconus.DesignRetrospective case series and literature review.ObservationsThis is a retrospective case series of eight patients presenting with keratoconus and IM, who were examined between January 2016 and December 2017 in the ophthalmology outpatient clinic. They had a median age of 14 (11–30), and all had bilateral keratoconus and diffusely distributed IM. The IM had similar presentations and similar iris colors. None had relevant medical or family diseases associated with IM. Three eyes previously had penetrating keratoplasty. Four (31%) out of 13 eyes had mean keratometry (Km) > 55D, and 4 (31%) had the thinnest pachymetry between 300 and 400μm.Conclusions and importanceTo the best of our knowledge, this is the first time that IM was observed in association with keratoconus patients. The possibility that IM is an early finding in otherwise healthy patients may help to predict the future diagnosis of keratoconus. Future studies are needed to show the frequency and possible association between IM and a keratoconus prognosis. This may also demonstrate that there is a subgroup of patients with a distinct etiology of keratoconus.

An unusual coexistence of iris mammillations and optic disc pit with keratoconus: A case report and literature review

“…reported for the first time a possible association between bilateral iris mammillations and keratoconus. [ 8 ] From 1995 to 2018, the reported ocular conditions associated with iris mammillations included myopia, amblyopia, esotropia, congenital ptosis, eyelid trichilemmoma, ipsilateral ocular melanocytosis, oculodermal melanocytosis, scleral pigmentation, iris hamartomas, persistent pupillary membrane, congenital cataract, congenital glaucoma, calcified ciliary body mass, choroidal melanoma, choroidal hemangioma, retinal detachment, optic neuritis, and optic nerve damage. [ 1 2 9 ] Based on these previously reported conditions, keratoconus was reported only recently in 2019.…”

“…[ 1 ] In addition to Lisch nodules, the differential diagnosis includes Brushfield flecks, iris melanoma, granulomatous iridocyclitis, iris nevi, Cogan-Reese iridocorneal endothelial syndrome, juvenile xanthogranuloma, and retinoblastoma. [ 1 2 8 10 ] In this case, the typical appearance of mammiform iris protuberances in addition to the absence of iris melanosis and systemic disorders were significant to diagnose this extremely rare ocular condition [ Figure 1 ]. Iris mammillations are distinctive, uniformly elevated, and regularly spaced smooth conical and villiform nodules, which sometimes stellate-like with tiny radiations emanating from the nodules bases, overlying areas of iris hyperpigmentation (naevi or iris melanosis), but not a pigmentary condition per se .…”