Changes of retinal structure and visual function in patients with demyelinating transverse myelitis

Area of Science:

• Neuro-ophthalmology
• Neuroimmunology

Background:

• Demyelinating diseases like aquaporin-4 IgG-positive neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein-associated disease (MOGAD), and multiple sclerosis (MS) can affect the central nervous system.
• Transverse myelitis (TM) is a form of myelitis characterized by inflammation across the spinal cord, and its association with specific neuroimmunological diseases without optic neuritis (ON) warrants investigation into potential ocular structural changes.

Approach:

• This retrospective cross-sectional study analyzed 97 patients with demyelinating TM without ON, categorized into AQP4-IgG-positive NMOSD, MOGAD, and MS groups.
• Optical coherence tomography (OCT) was used to measure retinal nerve fiber layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) thickness.
• Visual acuity and visual field tests assessed functional outcomes, with comparisons made to age-matched healthy controls.

Key Points:

• All TM patient groups exhibited reduced mean RNFL and GCIPL thickness compared to healthy controls, indicating retinal microstructural damage.
• While RNFL thickness reduction was consistent across TM groups, GCIPL thinning was significantly more pronounced in AQP4-IgG-positive NMOSD-TM and MS-TM patients compared to MOGAD-TM patients.
• Despite structural alterations, visual function, assessed by visual acuity and visual field tests, was generally well-preserved across all TM patient groups.

Conclusions:

• Demyelinating TM, irrespective of the underlying disease entity (NMOSD, MOGAD, MS), leads to distinct patterns of retinal microstructural damage.
• The observed retinal damage is more severe in AQP4-IgG-positive NMOSD and MS-TM compared to MOGAD-TM, particularly affecting the GCIPL.
• Current findings suggest that while retinal microstructural integrity is compromised in TM, this damage does not significantly impair visual function in the studied patient cohorts.