Case Report: Optic Disc Melanocytoma with PHOMS-Minimum Intensity Projection Image.

Abstract

Optic disc melanocytoma (ODMC) with peripapillary hyperreflective ovoid mass-like structures (PHOMS) is rare. This study reports a case of the characteristics of multimodal imaging and Minimum intensity projection (Min-IP) images. A 25-year-old male patient was referred to our hospital due to the presence of a dark pigmented tumor located in the optic disc area of his left eye. The patient exhibited normal pupillary reactions and had a best corrected visual acuity of 1.0 (decimal) in both eyes. This patient underwent multimodal retinal imaging examination including color fundus photograph (CFP), B-scan ultrasonography, Fundus autofluorescence (FAF), SD-OCT (spectral-domain optical coherence tomography), OCTA (optical coherence tomography angiography), en-face Min-IP image and fluorescein angiography (FA). CFP revealed a slightly elevated mass lesion in the inferior quadrant of the left optic disc, the lesion appeared black to dark brown in color. B-scan ultrasonography of the left eye confirmed the presence of a hyperechoic small dome-shaped lesion. Fundus autofluorescence (FAF) analysis revealed complete hypofluorescence in this area. SD-OCT (spectral-domain optical coherence tomography) and OCTA (optical coherence tomography angiography) with Min-IP were performed over the tumor and its surrounding areas. SD-OCT showed an elevated tumor mass arising from the optic disc with increased reflectivity. PHOMS appeared ovoid in shape on B-scan OCT image. PHOMS appeared peripapillary hyperreflective bright areas on en-face Min-IP image corresponding to PHOMS on B-scan OCT image. The fluorescein angiography (FA) showed the staining of PHOMS. A diagnosis of optic disc melanocytoma with PHOMS was established prompting the patient to be advised for regular follow-up. The optic disc melanocytoma with PHOMS is a rare benign ocular lesion that requires minimal active intervention, but demands a lifetime follow-up. The multimodal imaging and Min-IP images have clinical diagnostic value.