Progression of limbal stem cell deficiency in aniridia correlates with degradation of palisade structures, gradual transformation of epithelial phenotype, onset of inflammation, and a corneal nerve deficit. IVCM can be useful in monitoring early- to late-stage degenerative changes in stem cell-deficient patients.

. Purpose:  To investigate the epidemiology of aniridia in the populations of Sweden and Norway. Methods:  A thorough search for aniridia patients has been performed in Sweden and Norway. All participants had a clinical ophthalmological examination documented through photography. Blood samples were taken for mutation analysis and pedigrees were established. Results:  A total of 181 patients with aniridia were identified in the two countries. This gives an age‐specific prevalence of 1:72 000 in the entire region, 1:70 000 in Sweden and 1:76 000 in Norway. A total of 124 individuals (69%) were examined. Male/female ratio was 0.94 (Sweden 0.85 and Norway 1.2). Mean age of the examined patients was 29 years and median age 25 years. We did not find any significant age difference between the two countries. The mean visual acuity (VA) was 0.19 (Sweden 0.19 and Norway 0.18).The number of families with more than one affected member was 31 and the number of sporadic cases was 40. Conclusion:  We have done a thorough search of the literature, but we have found no earlier studies describing aniridia in an entire country and only a few reports from larger areas. We assume that most aniridia patients have been found and the aniridia prevalence of 1:72 000 can be regarded as well supported. Further studies on other aspects of aniridia are in progress, and information from these can contribute to guidelines for the care of patients with this rare but serious disease.

Objective: To document the clinical and morphologic corneal findings in the early stages of congenital aniridic keratopathy in Swedish families. less thanbrgreater than less thanbrgreater thanDesign: Prospective, observational, comparative case series. less thanbrgreater than less thanbrgreater thanParticipants: A total of 16 eyes of 16 subjects with congenital aniridic keratopathy and a clear central cornea, and 6 eyes from 6 healthy controls (unaffected relatives). Nine of the 16 eyes with aniridia came from 5 families with a documented familial history of aniridia. less thanbrgreater than less thanbrgreater thanMethods: Detailed ophthalmic examinations included best spectacle-corrected visual acuity (BSCVA), tear film production, tear break-up time (BUT), corneal touch sensitivity, intraocular pressure measurement, ultrasound pachymetry, slit-lamp biomicroscopy, and laser scanning in vivo confocal microscopy (IVCM). less thanbrgreater than less thanbrgreater thanMain Outcome Measures: Confirmed stage of aniridic keratopathy, clinical parameters of cornea and tear film (visual acuity, sensitivity, corneal thickness, tear production, and BUT), and the morphologic status of corneal epithelium, sub-basal nerves, and limbal palisades of Vogt. less thanbrgreater than less thanbrgreater thanResults: In early-stage aniridic keratopathy, BSCVA and tear BUT were reduced relative to controls (P andlt; 0.001 for both), and corneal thickness was increased (P = 0.01). Inflammatory dendritic cells were present in the central epithelium in aniridia, with significantly increased density relative to controls (P = 0.001). Discrete focal opacities in the basal epithelial region were present in 5 of 11 aniridia cases with an otherwise clear cornea. Opacities were associated with dendritic cells and harbored structures presumed to be goblet cells. Sub-basal nerves were extremely dense in 3 aniridia cases, and a prominent whorl pattern of nerves and epithelial cells was observed in 1 case. Normal limbal palisade morphology was absent in aniridia but present in controls. less thanbrgreater than less thanbrgreater thanConclusions: Early-stage aniridic keratopathy is characterized by the development of focal opacities in the basal epithelium, altered sub-basal nerves, infiltration of the central epithelium by dendritic cells, tear film instability, and increased corneal thickness and degradation of limbal palisade architecture. These findings may help to elucidate the pathogenesis of aniridic keratopathy. less thanbrgreater than less thanbrgreater thanFinancial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Funding Agencies|European Union||Crown Princess Margaretas Foundation for the Visually Impaired||Swedish Eye Fund||Carmen and Bertil Regners Foundation||David and Beth Dahlins Foundation||King Gustav V and Queen Victorias Freemasons Foundation||County Council of Ostergotland||Association of the Blind in Ostergotland||

This research identified the presence of visible keratopathy in 80% of eyes. In addition, 26% of eyes had a keratopathy level that caused visual disturbances. The study showed that the prevalence and severity of keratopathy increased with the patient's age. Further conclusions are that intraocular surgery increases the severity of keratopathy and that the severity of keratopathy is correlated to reduced corneal sensitivity. Finally, extreme care should be taken when selecting patients for intraocular surgery because this procedure can trigger the development of keratopathy.