4.6 Macular Pseudohole 221
A macular pseudohole resembles a full- thickness macular hole in terms of its shape, but the pathophysiology is quite different. The pseudohole is created by spontaneous contrac- tion of an epiretinal membrane surrounding the fovea. The pseudohole is not a retinal hole but a round defect of the epimacular membrane over the fovea. The natural course of a macular pseudohole is generally good, with preserva- tion of near-normal visual acuity [1]. In some cases, however, further contraction of the epiretinal membrane distorts the fovea, result- ing in decreased visual acuity.
A fundus photograph and an OCT image of an eye with a macular pseudohole are shown in Fig. 4.26. When the focal macular ERG elicited by a 15° spot was analyzed [2], we found a significant correlation between the reduction of the a-waves and b-waves and the parafoveal thickness (Fig. 4.27). There was a significant reduction in the mean amplitudes of the a-
waves, b-waves, and OPs in the affected eyes compared with fellow eyes. The relative ampli- tudes of the a-wave, b-wave, and OPs were 84.0%, 74.8%, and 62.4%, respectively. Thus, the decrease in the amplitude was greatest for the OPs followed by the b-waves and then the a- waves. The implicit times of a-waves, b-waves, and OPs were delayed significantly. These results were similar to those obtained from eyes with an idiopathic epimacular membrane without a macular pseudohole (see Section 4.3).
A significant correlation was found between the relative amplitude (affected eye/normal fellow eye) of the b-wave elicited by the 5° stim- ulus and the visual acuity (Fig. 4.28). This cor- relation probably resulted from using the 5°
spot, which is small and reflects the function of the small central area where the epiretinal membrane is absent.
4.6 Macular Pseudohole
Fig. 4.26. Fundus photograph (top) and OCT image (bottom) in a 56-year-old woman with a macular pseudohole. Visual acuity was 1.0
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222 4 Acquired Macular Diseases
References
1. Creven CM, Slusher MM, Czyz CN (1998) The natural history of macular pseudoholes. Am J Oph- thalmol 125:360–366
2. Suzuki T, Terasaki H, Niwa T, Mori M, Kondo M, Miyake Y (2003) Optical coherence tomography and focal macular electroretinogram in eyes with epiretinal membrane and macular pseudohole. Am J Ophthalmol 136:62–67
Fig. 4.27. There was a significant correlation between the relative amplitudes (affected eye/fellow eye) of the a-wave (top) and the b-wave (bottom) elicited by a 15° spot and the thickness of the parafoveal retina in patients with a macular pseudohole. (a-wave:
r= 0.674, P = 0.0006; b-wave: r = 0.804; P < 0.0001) (From Suzuki et al. [2], with permission)
Fig. 4.28. There was a significant correlation between the relative amplitudes of the b-wave elicited by a 5° spot and best-corrected visual acuity (VA). (r= 0.918, P = 0.0005) (From Suzuki et al. [2], with permission)
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