Abstract
Purpose :
Axenfeld Rieger syndrome (ARS) is a category of anterior segment dysgenesis (ASD) of neural crest origin with typical clinical features. However many cases present with atypical or overlap of clinical features with other categories of ASD. This observational study highlights lacunae in current classification system of ASD and the possible role of viral etiology.
Methods :
Hospital database of a tertiary eye centre in East India was retrospectively reviewed from 2009 to 2014 to identify cases of ARS with atypical presentation (typical ocular features were defined as presence of posterior embryotoxon and focal bridging iris strands in the angle with or without iris changes like stromal hypoplasia, corectopia, polycoria, ectropion uvea). Demographic data, family history, intraocular pressure with goldmann applanation tonometry (GAT), anterior segment findings on slit lamp and gonioscopic features were retrieved.
Results :
Out of 33 eyes with ARS, a total 17 eyes of 11 cases (M:F 9:2) were identified with atypical features. Mean age at diagnosis was 28.4±17.7 years. Six cases (55%) were bilateral and 3 (27%) were unilateral while laterality could not be assessed in 2 cases due to total corneal scar. Fifteen eyes had atypical prominent broad based anterior synechiae (different from bridging strands) seen on slit lamp extending >2 clock hours (figure 1) with prominent schwalbe’s line in only 6 eyes. These synechiae were non-progressive in nature and present at diagnosis. Associated pigmented keratic precipitates were present adjacent to these synechiae in 2 eyes (figure 1 & right inset in figure 2). One case had peripheral beaten metal corneal appearance in 1 eye (left inset in figure 2) as seen in Iridocorneal endothelial syndrome. Two eyes presented with features of recurrent anterior uveitis and negative viral polymerase chain reaction on anterior chamber tap, but responsive to anti-viral treatment (initiated based on clinical suspicion). One case had aniridia in 1 eye and ARS in other eye.
Conclusions :
Broad non-progressive anterior synechiae with no/minimal iris stromal hypoplasia may be a feature of atypical ARS. Significant overlap with other ASD entities in same or contralateral eye suggests common developmental etiologies and necessitate newer classification system for anterior segment dysgenesis. Viral uveitis in such cases indicate the possible role of viral insult at birth in pathogenesis of ASD with reactivation later in life.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.