THE SPECTRUM OF INTERNAL LIMITING MEMBRANE DISEASE IN ALPORT SYNDROME: A Multimodal Imaging Study

Area of Science:

• Ophthalmology
• Medical Imaging
• Genetics

Background:

• Alport syndrome is a genetic disorder affecting collagen production, leading to kidney, hearing, and eye abnormalities.
• Internal limiting membrane (ILM) disease is a known ocular manifestation of Alport syndrome, but its full spectrum and imaging characteristics require further elucidation.

Purpose of the Study:

• To characterize the spectrum of internal limiting membrane (ILM) disease in Alport syndrome using multimodal imaging (widefield and ultra-widefield).
• To determine the prevalence of these ILM findings based on the genetic pattern of inheritance in Alport syndrome.

Main Methods:

• A cross-sectional study involving 21 patients with Alport syndrome (42 eyes).
• Utilized ultra-widefield (UWF) color photography and autofluorescence, widefield (WF)-optical coherence tomography (OCT) angiography, and spectral-domain OCT (SD-OCT).
• Collected demographic, clinical, ophthalmic, and genetic mutation data.

Main Results:

• SD-OCT revealed ILM granularity, more common in X-linked Alport syndrome, correlating with dot maculopathy.
• Mid-peripheral SD-OCT showed progressive multilamellated ILM in 19% of eyes, appearing as a cavitary pattern on en-face OCT.
• En-face OCT identified retinal nerve fiber layer (RNFL) dehiscence and a coarse RNFL arrangement in 52% of eyes, overlapping with vascular lacunae.

Conclusions:

• Multimodal imaging effectively detected and characterized diverse retinal findings associated with ILM disease in Alport syndrome.
• Identified ILM granularity, progressive ILM lamellation, RNFL dehiscence, vascular lacunae, and coarse RNFL arrangement as key manifestations.
• These findings highlight the multifaceted nature of ILM disease in Alport syndrome, emphasizing the utility of advanced imaging techniques.