Background: After full macular translocation (MT) surgery with 360 degrees retinotomy, the fovea is rarely identifiable. Our aim was to verify the position of the fovea, to determine how patients fixate after MT and to examine distribution and optical density of macular pigment (MP).
Methods: 9 patients after MT were investigated. The Utrecht Macular Pigment Reflectometer was used to quantify the MP optical density. A Scanning Laser Ophthalmoscope (SLO) was used to identify the fovea as the centre of MP distribution and determine the retinal locus of fixation.
Results: In all patients, we identified the fovea as the centre of MP distribution. The retinal areas used for fixation were displayed by SLO fixation analysis. Comparing their spatial relationship with the fovea, five patients fixated centrally and four eccentrically up to 7.5 degrees. In those patients, microperimetry showed that the atrophy caused by choroidal neovascularization (CNV) extraction prevented central fixation.
Conclusion: The combination of MP distribution and fixation analysis permits quantifying fixation behaviour even if the fovea morphologically cannot be localized. Our results suggest that the scotoma caused by spreading chorioretinal atrophy is the main cause for reduced visual acuity after MT and therefore the MT rotation angle is crucially important.