MORPHOLOGICAL CHARACTERISTICS AND VISUAL ACUITY OF HIGHLY MYOPIC EYES WITH DIFFERENT SEVERITIES OF MYOPIC MACULOPATHY

To investigate the morphological feature, visual acuity, and prevalence of macular complications in highly myopic eyes with different categories of myopic maculopathy (MM) according to the META-PM classification system.

The clinical records of 1,132 consecutive patients (1,841 eyes) with high myopia (refractive error ≤ -6D and axial length ≥26.5 mm), who visited the High Myopia Clinic at the Zhongshan Ophthalmic Center from January 2014 to July 2017, were reviewed. Fundus photograph, optical coherence tomography, axial length, refractive error, and best-corrected visual acuity were measured in each patient. Myopic maculopathy was graded from fundus photographs according to the META-PM classification, including tessellated fundus (C1), diffuse chorioretinal atrophy (C2), patchy atrophy (C3), and macular atrophy (C4). Other macular complications, including foveoschisis, extrafoveal schisis, full-thickness macular hole, epiretinal membrane, lacquer cracks, Fuchs spot, choroidal neovascularization, macular hemorrhage, and dome-shaped macula, were also investigated.

Among the 1,841 eyes, 58 (3.15%) had no MM (C0), 779 (42.31%) had tessellated fundus only (C1), 524 (28.46%) had diffuse chorioretinal atrophy (C2), 352 (19.12%) had patchy chorioretinal atrophy (C3), and 128 (6.95%) had macular atrophy (C4). Age increased and best-corrected visual acuity became worse with the severity of MM (P < 0.01). Axial length was significantly longer with the severity of MM from C0 to C3 (P < 0.01), and spherical equivalent was greater with the severity of MM from C0 to C3 (P < 0.01) but was not different between C3 and C4 (P > 0.05). Subfoveal and parafoveal choroidal thicknesses were significantly thinner from C0 to C3 (P < 0.01). However, no significant difference was found between C3 and C4 in parafoveal choroidal thickness (P > 0.05). The complications were different among C0 to C4 correlated with MM (P < 0.01). The complications of foveoschisis, choroidal neovascularization, hemorrhage, lacquer cracks, Fuchs spot, dome-shaped macula, and epiretinal membrane were different between C1 and C2 (P < 0.01), but none of the complications were different between C3 and C4 (P > 0.05) except Fuchs spot (P = 0.009).

The morphological and functional characteristics in eyes with high myopia were positively correlated with the severity of C0 to C3 MM. However, no morphological difference was found between C3 and C4. The absence of the progressive relationship between C3 and C4 might be determined.