Successful management of choroidal neovascular membrane secondary to choroidal osteoma with intravitreal bevacizumab.

A 35-year-old female presented with sudden painless loss of vision since 7 days in right eye. Her best corrected visual acuity (BCVA) was 6/24 in right eye while left eye was within normal limits. Right eye fundus examination revealed a minimally elevated well defined orange-yellow lesion with irregular margins and large hypo-pigmented areas at the posterior pole suggestive of choroidal osteoma (CO) (Fig 1A). The maximum height of the lesion was beneath the fovea with a grayish subretinal membrane having an adjacent bleed, diagnostic of choroidal neovascular membrane (CNVM) (Fig 1). Ultrasound of right eye demonstrated a high spiking calcified plaque with acoustic shadow at macula, measuring 7.8 × 6.5 mm, further confirming the diagnoses of CO (Fig 1B). Fluorescein angiography revealed leakage corresponding to active CNVM with surrounding areas of mottled pigmentation (Fig 1C) while optical coherence tomography (OCT) revealed the neovascular membrane with minimal subretinal fluid and subretinal pigment epithelium (RPE) calcification corresponding to CO (Fig 1D). The patient received 3 intravitreal injections of bevacizumab (1.25 mg), each a month apart following which her BCVA marginally improved to 6/12 and the CNVM with the subretinal fluid resolved (Fig 2A and B). Dense pigmentation was noted corresponding to thick RPE seen on OCT. Choroidal osteoma remained unaffected. Patient was explained the need of repeated injections and risks of chronic RPE damage due to CO and kept on regular follow-up. At 12 month, her BCVA, fundus and OCT were stable as before.

Figure 1

A: Fundus photography depicting choroidal osteoma with choroidal neovascular membrane (white arrow) and accompanying subretinal bleed; B: ultrasound image of the right eye posterior pole showing calcified plaque (white arrow) in the outer coats corresponding to osteoma; C: Fluorescein angiogram of the right eye. Note mottled pigmentation corresponding to osteoma along with CNVM (white arrows); D: OCT images of the right eye showing the CNVM with accompanying subretinal fluid (white arrow). Sub RPE calcification corresponding to osteoma can also be seen as hyper reflective shadows (white arrow head).

Figure 2

A: Fundus photography showing dense pigmentation and resolved CNVM post treatment (3 months). Osteoma remains unaffected by the treatment; B: OCT image of right eye after treatment depicting resolved CNVM and subretinal fluid (3 months). Note thickened RPE (white arrow) corresponding to the area of pigmentation in Fig. 2A.

Comment

Choroidal osteoma (CO) is a rare ossifying tumor often associated with complications such as serous retinal detachment, RPE atrophy and CNVM. As nearly a third of patients with CO develop a CNVM, it is the most common cause of visual loss. Previous treatments such laser or photo dynamic therapy had been unsatisfactory with long-term RPE loss following treatment. However, recent evidence indicates better outcomes with multiple anti VEGF injections.2, 3 In our case too, visual improvement was noted following anti VEGF injections, thus echoing its efficacy. The clinician should explain the long-term prognoses and be aware of other differential diagnoses of CO such as melanoma, metastasis and sclera choroidal calcification.

Conflict of interest

The author declares that there is no conflict of interest.