From the Ocular Oncology Service, Wills Eye Institute, Thomas Jefferson University, Philadelphia, Pennsylvania.
Supported by the Eye Tumor Research Foundation, Philadelphia, Pennsylvania (CLS).
The authors have no proprietary or financial interest in the materials presented herein.
Address correspondence to Carol L. Shields, MD, Ocular Oncology Service, Suite 1440, Wills Eye Institute, 840 Walnut Street, Philadelphia, PA 19107. E-mail: email@example.com
Choroidal osteoma is a rare intraocular osseous tumor more often seen in healthy eyes of young women, the youngest reported case of which was in a 3-year-old girl.1,2 It is typically yellow-white to orange-red in color with fairly defined margins in a geographic pattern, occasional pigment clumping, and often in a juxtapapillary location.3 This tumor is generally benign but can adversely affect vision when associated with choroidal neovascular membrane, subretinal fluid, and photoreceptor atrophy.2 Further, growth has been observed in approximately 50% of cases.4
We describe a 7-year-old girl with bilateral subfoveolar choroidal osteoma that showed progressive growth and discuss current treatment alternatives.
A 7-year-old girl in good health was referred for retinal dystrophy in both eyes detected during routine examination. Ocular, medical, and family histories were unremarkable. On initial presentation, visual acuity was 20/20 in the right eye and 20/30 in the left eye. Intraocular pressures and slit-lamp examination results were normal in both eyes. Fundus examination showed a solitary subfoveolar, orange-colored choroidal tumor in each eye measuring 4 × 3 × 0.9 mm in the right eye and 7 × 7 × 0.9 mm in the left eye without subretinal fluid, hemorrhage, exudation, or retinal pigment epithelium alterations (Figs. 1A and 1B). Ultrasonography confirmed flat calcified choroidal tumors, whereas optical coherence tomography (OCT) demonstrated intact retina and a normal photoreceptor layer (Figs. 1C to 1F). The clinical findings were consistent with choroidal osteoma in both eyes. Treatment options include observation versus methods to halt tumor growth such as photodynamic therapy or laser photocoagulation. However, because tumor decalcification would induce photoreceptor atrophy in the foveola with subsequent visual loss, the family elected observation and we recommended calcium supplementation.
Figure 1. A 7-year-old girl presented with bilateral subfoveolar choroidal osteomas. Fundus photographs of the right (A) and left (B) eyes on initial presentation showed an orange-colored choroidal tumor involving the fovea measuring 4 × 3 and 7 × 7 mm, respectively. Visual acuity was 20/20 in the right eye and 20/30 in the left eye. Ultrasonography confirmed flat calcified choroidal tumors of 1-mm thickness in the right (C) and left (D) eyes. Optical coherence tomography of the right (E) and left (F) eyes showed intact inner and outer retina with normal foveal contour.
Three years later, minimal tumor growth of 1 mm in diameter was documented in both eyes. There was no decalcification, choroidal neovascularization, subretinal fluid, or photoreceptor atrophy detected on OCT (Fig. 2). Visual acuity was maintained at 20/20 in the right eye and 20/30 in the left eye.
Figure 2. After 3 years, fundus photographs and optical coherence tomography of the right (A and C) and left (B and D) eyes showed basal diameter enlargement of 1 to 2 mm without decalcification or photoreceptor atrophy on optical coherence tomography. Visual acuity was preserved in both eyes.
The natural course and visual prognosis of choroidal osteoma at 10 years reveal that this benign tumor can show enlargement in 51%, decalcification in 46%, visual acuity loss of 3 or more lines in 45%, and poor visual acuity of 20/200 or worse in 56%.3 Other less common features include subretinal hemorrhage and subretinal fluid associated with choroidal neovascular membrane, occurring in 30% of cases.1 If there is decalcification in the area of the macula, poor visual acuity results, usually due to photoreceptor atrophy.4 However, a decalcified border of a tumor shows little to no growth in that direction and thus results in the stabilization of the tumor scar.3
In a comprehensive report of 74 cases of choroidal osteomas by Shields et al., the estimated growth rate was 0.37 mm per year and growth was mostly uniform.3 Growth was not detected along a decalcified margin, but the remainder of the calcified tumor was at risk for growth. Although decalcified areas have been correlated to tumor stability, it is negatively associated with vision. The same authors showed patients with subfoveolar choroidal osteoma are at risk for poor visual outcome (< 20/200) if the tumor is decalcified (48%) versus calcified (22%).3 Further, decalcification imparts a relative risk of 3.6 for final visual acuity of 20/200 or worse, especially when subfoveolar as seen in our patient.3
OCT has been evaluated in a series of 22 eyes with choroidal osteoma and revealed that the inner and outer retina was intact overlying calcified portions of choroidal osteoma but the retina was thinned with photoreceptor loss over decalcified portions.5 By OCT, the decalcified portion specifically demonstrated tumor surface irregularity and overlying retinal pigment epithelium atrophy with outer retinal layer atrophy and intact inner layers.5 Despite knowing the effects of tumor decalcification on the overlying retina, there has not been any proven method of maintaining calcification of subfoveolar choroidal osteomas. In contrast to intraocular osseous tumors, however, calcium supplements have been proven to maintain bone calcification, especially in children.6,7 Further, they have also been shown to cause a decrease in bone resorption markers, bone formation markers, and parathyroid hormone levels, reflecting an overall reduction in bone turnover rate that did not persist after calcium withdrawal.7 Our patient was given the recommended daily calcium intake for children with the hopes that the effects of calcium supplementation on decreasing overall bone turnover may extend to intraocular osseous tissue. On the other hand, laser photocoagulation and photodynamic therapy have been proven to induce decalcification and this approach can be employed to halt further subfoveal growth of an extrafoveal choroidal osteoma.4,8
In contrast to the slow onset of visual loss from photoreceptor atrophy, acute loss of vision can occur with subretinal hemorrhage or subretinal fluid from choroidal neovascular membrane. In these instances, fluorescein angiography can differentiate the branching vascular tufts intrinsic to choroidal osteoma from the choroidal neovascular membrane.1 Treatment of choroidal neovascular membrane overlying the choroidal osteoma include laser photocoagulation, transpupillary thermotherapy, photodynamic therapy, surgical removal, and, more recently, intravitreal anti-vascular endothelial growth factors agents.4,8,9 Currently, the latter is the preferred therapy and, in some instances, additional consolidation with transpupillary thermotherapy or photodynamic therapy for extrafoveal choroidal neovascular membranes is applied. It should be realized that both photodynamic therapy and transpupillary thermotherapy might also induce decalcification.
Choroidal osteoma is a rare, benign intraocular tumor with slow, progressive growth and potential for substantial visual loss. Maintenance of tumor calcification could allow preservation of vision in eyes with subfoveolar tumors. The role of calcium supplementation in maintaining calcification of choroidal osteomas is unknown and would need further investigation.
- Shields CL, Shields JA, Augsburger JJ. Choroidal osteoma. Surv Ophthalmol. 1988;33:17–27. doi:10.1016/0039-6257(88)90069-0 [CrossRef]
- Mizota A, Tanabe R, Adachi-Usami E. Rapid enlargement of choroidal osteoma in a 3-year-old girl. Arch Ophthalmol. 1998;116:1128–1129.
- Shields CL, Sun H, Demirci H, Shields JA. Factors predictive of tumor growth, tumor decalcification, choroidal neovascularization, and visual outcome in 74 eyes with choroidal osteoma. Arch Ophthalmol. 2005;123:1658–1666. doi:10.1001/archopht.123.12.1658 [CrossRef]
- Aylward GW, Chang TS, Pautler SE, Gass JD. A long-term follow-up of choroidal osteoma. Arch Ophthalmol. 1998;116:1337–1341.
- Shields CL, Perez B, Materin MA, Mehta S, Shields JA. Optical coherence tomography of choroidal osteoma in 22 cases: evidence for photoreceptor atrophy over the decalcified portion of the tumor. Ophthalmology. 2007;114:e53–e58. doi:10.1016/j.ophtha.2007.07.037 [CrossRef]
- Lee WT, Leung SS, Wang SH, et al. Double-blind, controlled calcium supplementation and bone mineral accretion in children accustomed to a low-calcium diet. Am J Clin Nutr. 1994;60:744–750.
- Lambert HL, Eastell R, Karnik K, Russell JM, Barker ME. Calcium supplementation and bone mineral accretion in adolescent girls: an 18-mo randomized controlled trial with 2-y follow-up. Am J Clin Nutr. 2008;87:455–462.
- Shields CL, Materin MA, Mehta S, Foxman BT, Shields JA. Regression of extrafoveal choroidal osteoma following photodynamic therapy. Arch Ophthalmol. 2008;126:135–137. doi:10.1001/archopht.126.1.135 [CrossRef]
- Song JH, Bae JH, Rho MI, Lee SC. Intravitreal bevacizumab in the management of subretinal fluid associated with choroidal osteoma. Retina. 2010;30:945–951. doi:10.1097/IAE.0b013e3181c720ca [CrossRef]