The Science behind the Tip
Nanophthalmos, small eye-big trouble
, is a form of microophthalmos which is not accompanied by other congenital anomalies and is often familial. Hyperopia is present from birth and the axial length is less than 20 mm. Angle-closure glaucoma occurs between the 4th and 6th decades of life.
Glaucoma surgery in nanophthalmos has an extremely high complication rate with disastrous visual results (1). Late choroidal effusion occurs in up to 50% of patients after trabeculectomy with mitomycin C (2).
A recent study of phacoemulsification and IOL in these patients shows that the results have improved and choroidal effusion is less likely to occur (5%), but that complications (for example malignant glaucoma and severe uveitis) are still common (3). Persistent choroidal effusion can be successfully treated by partial thickness sclerectomy, which suggests that reduced scleral permeability to protein secondary to thickened sclera plays a pathophysiological role in this complication (4).
Contributor: John Salmon, Oxford
References
Singh OS, Simmons RJ, Brockhurst RJ, et al. Nanophthalmos: a perspective on identification and therapy. Ophthalmology. 1982;89:1006-12.
Yalvac IS, Satana B, Ozkan G, et al. Management of glaucoma in patients with nanophthalmos. Eye. 2008;22:838-43.
Day AC, MacLaren RE, Bunce C, et al. Outcomes of phacoemulsification and intraocular lens implantation in microphthalmos and nanophthalmos. J Cataract Refract Surg. 2013;39:87-96.
Johnson MW, Gass JD. Surgical management of the idiopathic uveal effusion syndrome. Ophthalmology. 1990;97:78-785.
Tip Reviewer: Roger Hitchings
Tip Editors: Ann Hoste, John Salmon and John Thygesen