Visual outcome correlates with inner macular volume in eyes with surgically closed macular hole

Abstract

Purpose: To determine the macular morphologic features that correlate best with visual outcome in eyes with surgically closed idiopathic macular hole.

Methods: Transversal observational case series of 24 eyes (22 subjects) imaged postoperatively using high-resolution Fourier domain optical coherence tomography (FD-OCT). Total and inner macular volume for central 3 mm area, central foveal thickness, and size of foveal inner segment-outer segment junction abnormality were correlated with best-corrected visual acuity. Microperimetry (MP-1) test was performed in a subset of 18 eyes.

Results: Mean postoperative best-corrected visual acuity was 20/36 (range, 20/25-20/70). Postoperative follow-up mean was 32.97 ± 24.68 months (range, 5-96 months). Eighteen eyes underwent internal limiting membrane (ILM) peeling. Among FD-OCT parameters, logarithm of the minimum angle of resolution best-corrected visual acuity and mean total microperimetry-1 sensitivity correlated best with inner macular volume in all eyes and ILM-peeled eyes (P < 0.05). Macular surface irregularities were noted in 12 eyes (66.7%) with ILM peeling but in none of the non-ILM-peeled eyes (P = 0.02). No significant correlation was found between microperimetry-1 sensitivity and other FD-OCT parameters.

Conclusion: Because inner macular volume strongly correlated with visual outcome in eyes with surgically closed macular hole, the possible effect of ILM peeling on visual outcome needs to be further investigated.

Fig. 1

High-resolution FD-OCT three-dimensional structure and corresponding thickness maps of the macula of an eye with surgically closed idiopathic macular hole. A. The segmented tMV volumetric data set is shown, from nerve fiber to retinal pigment epithelial layer. Note the retinal surface irregularities (solid white arrow) in this eye that had ILM peeling. B. The corresponding color-coded retinal thickness map for tMV measurement. C. The segmented three-dimensional volumetric data set for iMV, that is, nerve fiber to inner plexiform layer is shown. D. The corresponding color-coded retinal thickness map for iMV measurement. The intersection of the vertical and horizontal black lines on Figure 1B and 1D represents the central fovea. Dashed circle denotes the central 3 mm zone for which macular volume was measured.

Fig. 2

Scatterplots showing the correlation between logMAR BCVA and FD-OCT parameters for 24 eyes: A. tMV, B. iMV, C. CFT, D. foveal photoreceptor IS-OS junction abnormality size.

Fig. 3

High-resolution FD-OCT B-scan images of eyes that had ILM peeling for surgical closure of macular hole. A. An eye with BCVA of 20/60 showing more severe macular surface irregularity (solid white arrow). This eye underwent a second vitrectomy with ILM peeling for recurrent macular hole. Note also the foveal photoreceptor IS-OS abnormality. B. An eye with BCVA of 20/30 with more subtle macular surface irregularity (solid white arrow) and mild epiretinal membrane peripheral to the irregularity. Foveal photoreceptor IS-OS abnormality is present again. Image A is a single frame image and Image B is an average of 10 frames.

Fig. 4

High-resolution FD-OCT B-scan image of an eye with surgically closed macular hole without ILM peeling. BCVA is 20/25 and no macular surface irregularity is noted. A small foveal photoreceptor IS-OS defect is present. This image is an average of 10 frames.

Fig. 5

Scatterplots showing the correlation between MP-1 sensitivity and logMAR BCVA and FD-OCT parameters for 18 eyes: A. Mean total MP-1 sensitivity (45 data points) and logMAR BCVA, B. Mean total MP-1 sensitivity (45 data points) and tMV, C. Mean total MP-1 sensitivity (45 data points) and iMV, D. Mean central MP-1 sensitivity (9 data points) and foveal photoreceptor IS-OS junction abnormality size.

Fig. 6

MP-1 (8° 10 dB strategy) and high-resolution FD-OCT image of an eye with surgically closed macular hole with ILM peeling. A. MP-1 sensitivity with numerical values for the 45 data points, B. MP-1 sensitivity color map (green denotes normal sensitivity, whereas yellow and orange denotes progressive loss of sensitivity, respectively) and C. the three-dimensional FD-OCT volumetric data set as viewed on volume visualization and image processing software; (i) the B-scan in XZ plane showing macular surface irregularity, (ii) the en face projection view of the volume showing the extent of the macular surface irregularity relative to the retinal vessels, (iii) the “virtual” B-scan in YZ plane reconstructed from volume through section of macula with less surface irregularity and (iv) the three-dimensional FD-OCT volume with surface irregularities. The dashed white circle represents the approximate area over which the MP-1 sensitivity assessment was done. For this eye, the BCVA postoperatively was 20/70, mean total MP-1 sensitivity of 45 data points was 13.30 dB and mean central MP-1 sensitivity of 9 data points was 5.33 dB and tMV and iMV for central 3 mm was 2.11 mm³ and 0.49 mm³, respectively. This is an example of an eye with poor MP-1 sensitivity and macular surface abnormality on FD-OCT B-scan. As shown, there is some correlation between the area of the macula with decreased sensitivity on MP-1 and the area of the macula with surface irregularity on FD-OCT.