From the Departments of Ophthalmology (FJA) and Radiology (RL), “Lozano Blesa” University Clinic Hospital; and Aragon Health Sciences Institute (FJA), Zaragoza, Spain.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to Francisco J. Ascaso, MD, PhD, Department of Ophthalmology, “Lozano Blesa” University Clinic Hospital, San Juan Bosco 15, ES-50009 Zaragoza, Spain. E-mail: firstname.lastname@example.org
Choroidal osteoma is a rare ossifying benign choroidal tumor that typically occurs in healthy young women as a circumscribed, unilateral, yellow-orange, slow-growing juxtapapillary lesion.1
We report the case of a 28-year-old woman who had been attended in our hospital since she was 12 years old. She presented in 1994 with gradual decrease in vision in the right eye over the past year. She had been blind in the left eye since childhood. There was no history of trauma, endocrine dysfunction, or hearing impairment. Her visual acuity was 20/400 in the right eye and 20/1600 in the left eye. Intraocular pressure, anterior segment examination, and ocular movements were normal in both eyes. The pupil of the left eye showed sluggish reaction to light. Funduscopy revealed a primary optic atrophy in the left eye (Fig. A) and a well-demarcated, slightly elevated, yellow-white to orange lesion located in the juxtapapillary and macular area of the right eye compatible with a choroidal osteoma (choroidal osteoma) (Fig. B).
Figure. (A) Funduscopy of the Left Eye Showed a Primary Optic Nerve Atrophy. (B) Right Fundus Photograph Revealed a Typical Choroidal Osteoma in the Juxtapapillary and Macular Area. (C) Orbital Computed Tomography Scan Demonstrated a Characteristic, Circumscribed, Homogeneously Radio-Opaque Plaque with the Same Density as Bone at the Level of the Choroid in the Right Eye (arrow), and Bilateral Calcification of the Dural Optic Nerve Sheath (arrowheads). Note the Calcification in Petroclinoid Ligament (black Arrows). (D) Cranial Computed Tomography Scan Showed Calcifications in the Pineal, Choroid Plexus, and Dura (falx and Tentorium) (asterisks).
B-scan ultrasonography confirmed the diagnosis. Serum calcium, phosphate, and parathyroid hormone levels were normal. Orbital computed tomography scan revealed a characteristic, well-defined, homogeneously radio-opaque plaque with the same density as bone at the posterior choroid in the right eye, bilateral optic nerve sheath calcification, and calcification of the petroclinoid ligaments (Fig. C). Cranial computed tomography scan showed calcifications in the pineal, choroid plexus, and dura (falx and tentorium) (Fig. D). Brain parenchyma and cerebellum were normal. Magnetic resonance imaging showed that the optic nerve calcification was limited to the nerve sheaths, but the choroidal lesion was not visible. During the past 16 years, visual acuity, tumor size, and intracranial calcifications have not changed.
Although choroidal osteoma has been associated with various ocular disorders such as retinitis pigmentosa, Stargardt’s dystrophy, or central serous retinopathy, these associations may be coincidental and the choroidal tumor could be related to a dysfunction of the retinal pigment epithelium or choriocapillary.2,3 The current case of choroidal osteoma was associated with calcified lesions of the optic nerves.
Of only six previously reported cases of optic nerve calcifications, two displayed unilateral profound intraorbital optic nerve calcification with no other intracranial calcium deposits, had unilateral optic atrophy and remote histories of severe optic nerve trauma, and the presumed mechanism was optic nerve hemorrhage.4 Four more cases were described as idiopathic and bilaterally affecting the dural optic nerve sheath. Although no further patient information was provided in one of them,5 two other cases showed bilateral optic atrophy and multiple intracranial calcifications.6 Another case noted no recent change in his vision, both optic nerve heads had a normal appearance, and no intracranial calcification was associated.7 The latter looks like a benign or early form of optic nerve calcification.
Similar to the patients described by Phadke et al.,6 our case showed a worse prognosis. The current case of bilateral dural optic nerve sheath calcification was associated with choroidal osteoma in the right eye and optic atrophy in the left eye. It is also the only reported female and the youngest one with optic nerve sheath calcifications.
The pathogenesis of bone formation in choroidal osteoma remains uncertain. Although several etiological factors have been associated with its onset, intraocular inflammation might be one of them. Only a few cases of choroidal osteoma associated with intraocular inflammation have been reported.8–10 Thus, Katz and Gass8 described a choroidal osteoma developing in association with recurrent orbital inflammatory pseudotumor. Trimble and Schatz9 reported a peripapillary choroidal osteoma that appeared some years after the onset of an inflammation. Casaroli-Marano et al.10 evaluated an unusual concurrence of bilateral choroidal osteoma after optic disk inflammation in a woman in whom optic neuritis was the first symptom of Behçet’s disease.
In our case, although the bilateral decreased visual acuity could be explained by the left optic atrophy and contralateral macular tumoral lesion, both of them might be the result of the bilateral optic nerve calcification. In addition, bilateral optic nerve sheath calcification associated with multiple intracranial calcifications would suggest an unexplained and generalized dural calcification process that rarely leads to optic nerve sheath calcification. Such calcification is in some cases vision threatening, as happened in our patient and other already mentioned reported cases.6,7 A dystrophic calcification could occur in degenerated tissues as a reaction to cell damage. This global response might be secondary, such as to an unknown subclinical meningitis.
- De Potter P, Shields JA, Shields CL, Rao VM. Magnetic resonance imaging in choroidal osteoma. Retina. 1991;11:221–223. doi:10.1097/00006982-199111020-00006 [CrossRef]
- Figueira EC, Conway RM, Francis IC. Choroidal osteoma in association with Stargardt’s dystrophy. Br J Ophthalmol. 2007;91:978–979. doi:10.1136/bjo.2006.098186 [CrossRef]
- Browning DJ. Choroidal osteoma: observations from a community setting. Ophthalmology. 2003;110:1327–1334. doi:10.1016/S0161-6420(03)00458-5 [CrossRef]
- Crompton JL, O’Day J, Hassan A. Optic nerve calcification after trauma. J Neuroophthalmol. 2004;24:293–294.
- Murray JL, Hayman LA, Tang RA, Schiffman JS. Incidental asymptomatic orbital calcifications. J Neuroophthalmol. 1995;15:203–208.
- Phadke RV, Agarwal P, Sharma K, Chauhan SS. Idiopathic duro-optic calcification: a new entity?Clin Radiol. 1996;51:359–361. doi:10.1016/S0009-9260(96)80116-4 [CrossRef]
- Nicholson BP, Lystad LD, Emch TM, Singh AD. Idiopathic dural optic nerve sheath calcification. Br J Ophthalmol. 2011;95:290,299. doi:10.1136/bjo.2008.157032 [CrossRef]
- Katz RS, Gass JDM. Multiple choroidal osteomas developing in association with recurrent orbital inflammatory pseudotumor. Arch Ophthalmol. 1983;101:1724–1727.
- Trimble SN, Schatz H. Choroidal osteoma after intraocular inflammation. Am J Ophthalmol. 1983;96:759–764.
- Casaroli-Marano RP, Molina JJ, Adán A, Corretger X. Bilateral choroidal osteoma associated with optic neuritis in Behçet’s disease. Ophthalmic Surg Lasers Imaging. 2010;41:e1–e4. doi: doi:10.3928/15428877-20100215-78 [CrossRef]