Abstract
Purpose: :
To evaluate the macular morphological changes in eyes with surgically closed idiopathic macular hole (MH) using high-resolution Fourier-domain optical coherence tomography (FD-OCT) and to correlate these findings with visual acuity outcome.
Methods: :
Laboratory prototype FD-OCT system developed at our institution with axial and transverse resolution of 4.5 µm and 10 to 15 µm respectively was used to evaluate the macula of 22 eyes of 20 subjects with surgically closed idiopathic MH. Volumetric data sets covering an area of 5x5x2mm and 6x6x2mm of the macula and 6mm serial horizontal B-scans were acquired. Post-operative best-corrected Snellen visual acuity (BCVA) was converted to logMAR VA and correlated with the following measured FD-OCT parameters: volume of the central 3000 µm of the macula, central foveal thickness (CFT), and size of the foveal inner-outer segment (IS/OS) junction defect.
Results: :
Among 22 eyes imaged, mean post-operative BCVA was 20/46 ± 29.92 (range: 20/25 to 20/150). All eyes had standard vitrectomy, 17 with internal limiting membrane (ILM) peeling and 5 without ILM peeling. Mean duration of follow-up was 30.36 ± 22.01 (range 5 to 96 months). Postoperative logMAR BCVA correlated with total macular volume (mean: 2.26±0.16 mm3, r = 0.58, p = 0.004) and volume of the macular inner retinal layers (nerver fiber layer to inner plexiform layer) (mean: 0.68±0.12 mm3, r = 0.65, p = 0.001). LogMAR BCVA did not correlate with volume of the outer retinal layers of the central macula (mean: 1.57 ± 0.07 mm3, r = 0.17, p = 0.44), CFT (mean: 174.31±28.49 µm, r = 0.10, p = 0.65) and size of the foveal IS/OS defect (mean: 24.7±21.2 µm, r = 0.26, p = 0.24). Retinal surface irregularities were noted in 12 eyes (70%) that had ILM peeling but in none of the eyes without ILM peeling.
Conclusions: :
Volume of the inner retinal layers of the macula appears to correlate with visual outcome in eyes with surgically closed idiopathic MH. Retinal surface irregularities were seen in a majority of eyes that had ILM peeling. The possible role of ILM peeling in affecting inner macular volume and visual outcome needs to be further investigated.
Keywords: macular holes • imaging/image analysis: clinical • vitreoretinal surgery