To the Editor:
In their otherwise excellent article, Sundin et al.1 erroneously state that the term “posterior microphthalmia” is synonymous with nanophthalmos. Although both conditions are characterized by shortened axial lengths and high hyperopia, in nanophthalmos anterior chamber dimensions are decreased1,2 whereas in posterior microphthalmos the anterior segment is of normal (or slightly subnormal) size.3,4,5 Thus the phenotype of posterior microphthalmos does not include the predisposition to angle-closure glaucoma that is part of nanophthalmos phenotype.3,4,5 Additional findings of posterior microphthalmos include retinal folds, occasional pigmentary retinopathy, and a propensity for uveal effusion.3,4,5 Published reports and my own experience suggest that posterior microphthalmos is a distinct autosomal recessive isolated ocular phenotype.3,4,5
REFERENCES
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