Subfoveal choroidal neovascularization in a 3-year-old child with North Carolina macular dystrophy David Y. Rhee, MD, Elias Reichel, MD, Adam Rogers, MD, and Mitchell Strominger, MD
North Carolina macular dystrophy is characterized by nonprogressive atrophy of the choroid, choriocapillaris, and the retinal pigment epithelial layer.1,2 The characteristic retinal findings, ranging from scattered drusen to a posterior staphyloma, have been reported as early as infancy and usually reach their greatest magnitude in the second decade of life.3 Herein, we describe a case of a 3-year-old boy with a documented family history of North Carolina macular dystrophy who presented with a subfoveal choroidal neovascular membrane in addition to the macular dystrophic changes.
Case Report A 3-year-old boy with a history of a retinal dystrophy was referred to the pediatric ophthalmology clinic at the New England Eye Center for a pediatric ophthalmologic examination. The patient was a former 32-week-old, 1770 g, premature child whose father had a documented history of North Carolina macular dystrophy. The patient had been examined at 34 weeks of gestational age in the neonatal intensive care unit at another institution during a routine screening for retinopathy of prematurity. There he was found to have bilateral atrophy of the choroid and retinal pigment epithelial layer that was confined to the macula, consistent with North Carolina macular dystrophy. On examination, visual acuity was 20/100 in the right eye and 20/25 in the left eye at distance by Allen picture testing. Near visual acuity was 20/63 in the right eye and 20/30 in the left eye. Stereopsis was not detectable by random dot and Titmus fly tests. The patient was able to correctly identify 13/14 Ishihara color vision plates with the right eye and 14/14 with the left eye. Versions were comitant bilaterally and the patient was orthotropic by cover testing. No nystagmus was noted. Both pupils reacted briskly to light, and there was no afferent pupillary defect. Slit-lamp examination of the external adnexae and anterior segment revealed no obvious abnormalities.
Author affiliations: Tufts-New England Medical Center, New England Eye Center, Boston, Massachusetts Submitted December 5, 2006. Revision accepted June 11, 2007. Published online October 3, 2007. Reprint requests: Mitchell Strominger, MD, Tufts-New England Medical Center, New England Eye Center, 750 Washington Street, Box 450, Boston, MA 02111 (email:
[email protected]). J AAPOS 2007;11:614-615. Copyright © 2007 by the American Association for Pediatric Ophthalmology and Strabismus. 1091-8531/2007/$35.00 ⫹ 0 doi:10.1016/j.jaapos.2007.06.010
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Cycloplegic retinoscopy demonstrated ⫹1.00 spherical refractive error in both eyes. On fundus examination, the patient was noted to have well-demarcated atrophy of the retinal pigment epithelium and choroid throughout most of the macular region in both eyes, corresponding to a grade 2 lesion, as described by Small4 (Figure 1A and B). When compared with previous photographs taken from the neonatal intensive care unit, this atrophy appeared relatively unchanged. In addition, the right eye also exhibited a large, involuted subfoveal neovascular membrane (Figure 1A), with nearby exudation (Figure 1A). The fibrovascular composition of the membrane suggested chronicity of the lesion. Fluorescein angiography was not performed at the request of the parents.
Discussion Lefler et al1 and Frank et al2 were the first to report a progressive, dominantly inherited foveal dystrophy that was characterized by good color vision and normal fullfield electroretinogram and electro-oculogram responses. Other previously characterized dystrophies, including central areolar pigment epithelial dystrophy, are now thought to be part of North Carolina macular dystrophy.7 Through linkage analysis, North Carolina macular dystrophy has been localized to chromosome 6q14-q16.2; however, no putative gene has yet been identified.6 Our patient did not undergo genetic testing, as the father stated he had already been analyzed previously and did not see the need for further testing. Atrophy of the choroid, choriocapillaris, or retinal pigment epithelium in North Carolina macular dystrophy has been described in young children as early as 3 months of age,5 and choroidal neovascularization has been observed in older patients with North Carolina macular dystrophy.4,5 To our knowledge, at a gestational age of 34 weeks, this is the youngest patient with North Carolina macular dystrophy to have documented macular atrophy. Both Gass3 and Small4 have reported visual acuities as poor as 20/200, with an average visual acuity in the small familial cohorts of 20/40 to 20/50. Most patients with North Carolina macular dystrophy with macular atrophy alone do not typically show progressive visual loss, although progressive visual decline can occur in these patients as a result of subfoveal neovascularization.5 The lifetime risk of subfoveal neovascularization and treatment modalities for the development of neovascularization have
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FIG 1. Fundus photographs of the right (A) and left (B) eye. Both eyes show well-demarcated atrophy of the retinal pigment epithelium and choroid in the macula. In addition, the left eye shows a fibrovascular subfoveal neovascular membrane (arrow) with associated exudation (arrowhead).
not been well studied. The possibility of intravitreal ranibizimab or bevacizumab as well as photodynamic therapy was discussed with the family; however, due to the young age of the patient, it was decided to carefully observe the patient. We believe that this is the youngest patient with North Carolina macular dystrophy with a documented choroidal neovascular membrane. We therefore recommend frequent follow-up for all pediatric patients with North Carolina macular dystrophy to monitor the development of subfoveal neovascular membranes.
Literature Search A MEDLINE search covering the years 1950 to 2007 was performed using the search terms North Carolina Macular Dystrophy, autosomal dominant macular dystrophy, dominant progressive foveal dystrophy, dominant macular degeneration with aminoaciduria, Lefler Wadsworth Sidbury syndrome, and
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autosomal dominant pattern dystrophy, although North Carolina Macular Dystrophy was not described until 1974. References 1. Lefler WH, Wadsworth JA, Sidbury JB Jr. Hereditary macular degeneration and amino-aciduria. Am J Ophthalmol 1971;71:224. 2. Frank HR, Landers MB III, Williams RJ, Sidbury JB. A new dominant progressive foveal dystrophy. Am J Ophthalmol 1974;78:903. 3. Gass JDM. Stereoscopic Atlas of Macular Diseases: Diagnosis and Treatment, 3rd ed. St. Louis (MO): C.V. Mosby Co.; 1987. p. 98-100. 4. Small KW. North Carolina macular dystrophy: Clinical features, genealogy, and genetic linkage analysis. Trans Am Ophthalmol Soc 1998;925-61. 5. Small KW. North Carolina macular dystrophy: In: Traboulsi EI, editor. Genetic Diseases of the Eye. New York (NY ):Oxford University Press; 1998. p. 367-71. 6. Small KW. North Carolina macular dystrophy is localized to 6q14q16.2. (Abstract) Am J Hum Genet 1992;51(Suppl):A34. 7. Small KW, Hermsen V, Gurney N, Fetkenhour CL, Folk JC. North Carolina macular dystrophy and central areolar pigment epithelial dystrophy: One family, one disease. Arch Ophthalmol 1992;110:515-8.