Abstract
Purpose :
Alport syndrome is an inherited disease characterised by renal failure, hearing loss, lenticonus and retinopathy that is caused by mutation of the type IV collagen genes. Because type IV collagen is a component of the ILM, ILM is impaired in Alport syndrome. This retrospective, cross-sectional clinical study was performed to investigate whether similar findings to postoperative changes after ILM peeling for macular holes may exist in eyes with Alport syndrome.
Methods :
The medical records of 6 eyes of 3 patients with Alport syndrome (age: 30, 41 and 42 years) were reviewed. Papillofoveal distance was measured in the Spectralis® fundus image in both eyes and compared with normal control eyes. In the horizontal Spectralis® OCT images, the thicknesses of different retinal layers (total retina, inner layer, layer between outer nuclear layer and ellipsoid zone (ONL-EZ), layer between ellipsoid zone and retinal pigment epithelium (EZ-RPE)) at 1000 μm nasally and temporally to the foveal centre were measured. Superficial en face OCT images were also evaluated.
Results :
The papillofoveal distance in Alport syndrome was significantly shorter than that in normal control eyes (4107.8±284.5 μm vs. 4430.5±129.7 μm, respectively; p <0.05). The thicknesses of total retina, inner layer, ONL-EZ, and EZ-RPE was 135.9±26.0, 61.5 ±15.0, 37.5 ±3.2, 36.9 ±11.2 μm at temporal side and 212.6±78.8, 130.9±54.3, 43.0±19.7, 38.8±13.8 μm at nasal side, respectively. The thicknesses of total retina, inner layer at temporal side was significantly thinner than nasal side (both p<0.05), and thicknesses of ONL-EZ and EZ-RPE were not significantly different (both p>0.05). Superficial en face images showed spindle-shaped dimples mainly in the temporal retina, which has a shape similar to that of the dimples observed after surgery with ILM peeling.
Conclusions :
The shorter papillofoveal distance, horizontal retinal thickness asymmetry, and inner retinal changes mainly found in temporal area in Alport syndrome were similar to the changes after ILM peeling for the macular holes. These similarities suggest that these changes are caused by the loss of ILM. ILM may have an important role in maintaining normal retinal structure.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.