Evaluation of visual functional and morphology change in young patients with idiopathic choroidal neovascularization

Idiopathic choroidal neovascularization (ICNV) is an uncommon disorder affecting primarily individuals younger than the age of 50 years. In CNV patients, no apparent cause can be determined. This study aimed to evaluate the functional and morphological change of the retina with ICNV in young adults.

In this retrospective study, 32 eyes of 32 patients with subfoveal or juxta/extra foveal ICNV had been admitted into the Shanghai First People's Hospital from January 2009 to July 2010. The functional changes were evaluated using the best corrected visual acuity (BCVA) and the microperimetry in the macular area. The morphology changes were evaluated using optical coherence tomography (OCT), the color fundus photography and the fluorescein angiography.

Seventeen patients with juxta/extra foveal and 15 subfoveal CNV were investigated. The mean logarithm of the minimum angle of resolution (LogMAR) BCVA was 0.39, the mean central retinal thickness (CRT) was 334 µm, and the mean sensitivity (MS) was 11.8 decibels (dB). In the subfoveal group, there was a strong correlation between CRT and BCVA (r = -0.675, F = 2.167, P < 0.01); as well as that between CRT and MS (r = -0.681, F = 22.91, P < 0.01). While in the juxta/extra foveal CNV group, the correlation of CRT and BCVA was not significant (r = -0.071, F = 1.018, P > 0.05); neither was the correlation of CRT and MS (r = -0.142, F = 36.54, P > 0.05). The microperimetry (MP-1) test revealed 17 (53%) patients with stable fixation, 9 (28%) with relatively unstable and 6 (19%) with unstable fixation. Fixation stability correlated positively with sensitivity in the central 2° diameter area (r = 0.380, F = 3.213, P < 0.05) and the duration of symptoms (r = 0.401, F = 7.933, P < 0.05).

ICNV was associated with reduced total MS, unstable fixation and eccentric fixation. These findings emphasized functional change in ICNV is beyond the BCVA and regular morphology change, which provided additional information of functional evaluation in clinical practice.