Abstract
Purpose: :
Choroidal naevi, the most common ocular fundus tumour, is present in 7% of the white population. Despite its benign nature, it carries a risk of visual loss and rarely malignant transformation. Moreover, flat choroidal nevi are not always detected by ultrasonography, hence the interest of other imaging modalities. The use of spectral domain optical coherence tomography (SD-OCT) for choroidal naevi diagnosis and follow up has not been evaluated yet .
Methods: :
Twenty eyes of 20 patients with one or several chroroidal nevi were examined with SD-OCT. The following parameters were analyzed: size(largest diameter, size of decreased posterior reflectivity, thickness), choroidal and retinal structure modifications, presence of drusen or orange pigment.
Results: :
The diameter of choroidal naevi ranged from 0.4 to 4 mm. Thickness was in all cases less than 2mm. In all cases the naevi appeared as hyperreflective lesions at the level of large choroidal vessels, masking the posterior choroid and the sclera, with preservation of the choriocapillaris. Orange pigment appears as a hyperreflective structure within pigment epithelium, whereas drusen were located at the subepithelial level. Retinal serous detachment was found in one patient.
Conclusions: :
OCT is a useful tool for quantitative and qualitative analysis of choroidal naevi. In particular, it allows the diagnosis of associated lesions undetectable by ultrasonography. Its specific interest for the differential diagnosis with melanoma an should be evaluated by a larger prospective study.
Keywords: choroid • tumors • oncology