Fixation and photoreceptor integrity in optical coherence tomography

Area of Science:

• Ophthalmology
• Retinal Imaging
• Visual Neuroscience

Background:

• Full-thickness macular holes (FTMH) and epiretinal membranes (ERM) are common retinal conditions.
• Eccentric fixation (EF) can occur in patients with these conditions, affecting visual acuity.
• Understanding the relationship between EF and photoreceptor integrity is crucial for managing these patients.

Purpose of the Study:

• To investigate the prevalence and characteristics of eccentric fixation (EF) in patients with FTMH and ERM.
• To explore the association between EF and the integrity of the photoreceptor inner segment/outer segment (IS/OS) junction.
• To compare EF in preoperative and postoperative stages of FTMH and ERM.

Main Methods:

• Eccentric fixation (EF) was quantified using spectral domain optical coherence tomography (SD-OCT) by measuring the distance between the scan center and foveal center.
• Photoreceptor integrity was assessed by evaluating the reflectivity of the IS/OS junction at both the scan center and foveal center.
• Comparisons were made between eyes with FTMH, ERM, and normal control eyes.

Main Results:

• Significantly greater EF was observed in eyes with preoperative FTMH, postoperative FTMH, preoperative ERM, and after ERM removal compared to normal eyes.
• Abnormal EF was more prevalent in eyes exhibiting greater IS/OS junction reflectivity at the scan center than at the foveal center.
• The amount of EF varied between preoperative and postoperative conditions, suggesting a dynamic relationship with the retinal pathology.

Conclusions:

• Eccentric fixation (EF) is frequently present in patients with FTMH and ERM.
• The degree of EF appears to be influenced by the integrity of the photoreceptor IS/OS junction.
• These findings suggest that photoreceptor integrity plays a role in the development or compensation of eccentric fixation in macular diseases.