Johns Hopkins University

Author Of 1 Presentation

Neuromyelitis Optica and Anti-MOG Disease Oral Presentation

YI02.01 - Optic Neuritis-Independent Retinal Atrophy In Neuromyelitis Optica Spectrum Disorders

Speakers
Presentation Number
YI02.01
Presentation Topic
Neuromyelitis Optica and Anti-MOG Disease
Lecture Time
11:15 - 11:27

Abstract

Background

Prior studies have suggested that retinal neuro-axonal loss may occur in aquaporin-4 (AQP4)-IgG seropositive neuromyelitis optica spectrum disorder (NMOSD) in the absence of optic neuritis (ON), but data are conflicting.

Objectives

To examine whether patients with AQP4-IgG seropositive NMOSD exhibit progressive retinal neuro-axonal loss, independently of optic neuritis (ON) attacks.

Methods

In this single-center, longitudinal study, 32 AQP4-IgG+ NMOSD patients and 48 healthy controls (HC) were followed with serial spectral-domain optical coherence tomography (OCT). NMOSD patients with ON less than 6 months prior to baseline were excluded, while data from patients with ON during follow-up were censored at the last visit prior to ON. Rates of peri-papillary retinal nerve fiber layer (pRNFL) and macular ganglion cell+inner plexiform layer (GCIPL) thinning were compared between groups utilizing mixed-effects linear regression models adjusted for age, race and sex.

Results

Median follow-up duration was 4.3 years (IQR: 2.6 -7.5) for the NMOSD cohort and 4.0 years (IQR: 1.8 – 7.5) for the HC. We observed faster pRNFL (β=-0.25µm/year, 95%CI: -0.45 to -0.05, p=0.014) and GCIPL thinning (β=-0.09µm/year, 95%CI: -0.17 to 0, p=0.05) in NMOSD compared to HC eyes. This difference appeared to be driven by faster pRNFL and GCIPL thinning in NMOSD eyes without a history of ON compared to HC (GCIPL: β=-0.15µm/year, 95%CI: -0.25 to -0.05, p=0.005; pRNFL: β=-0.43µm/year, 95%CI: -0.67 to -0.19, p<0.001), while rates of pRNFL (β=-0.07µm/year , 95%CI: -0.31 to 0.16, p=0.53) and GCIPL (β=-0.01µm/year, 95%CI: -0.11 to 0.10, p=0.90) thinning did not differ between NMOSD-ON and HC eyes .

Furthermore, we explored the effects of non-ON relapses during follow-up on rates of pRNFL and GCIPL thinning. Ten patients had relapses during follow-up (9 transverse myelitis, 1 area postrema syndrome). Patients with relapses did not exhibit differences in rates of GCIPL (β=0.05µm/year, 95%CI:-0.10 to 0.20, p=0.51) or pRNFL thinning (pRNFL: β=0.08µm/year, 95%CI: -0.28 to 0.43, p=0.67), compared to those who were clinically stable.

Conclusions

In this longitudinal study, we observed progressive pRNFL and GCIPL atrophy in AQP4-IgG+ NMOSD eyes unaffected by ON. These results support that subclinical involvement of the anterior visual pathway may occur in AQP4-IgG+ NMOSD.

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Author Of 2 Presentations

Biomarkers and Bioinformatics Poster Presentation

P0036 - Cerebral hypometabolism is a marker of disease severity in multiple sclerosis: a non-invasive imaging study using T2-Relaxation-Under-Spin-Tagging MRI (ID 1856)

Speakers
Presentation Number
P0036
Presentation Topic
Biomarkers and Bioinformatics

Abstract

Background

Metabolic dysfunction at a cellular level is a crucial element of progressive neuronal dysfunction, and ultimately neurodegeneration in multiple sclerosis (MS). Changes in retinal superficial vascular plexus (SVP) density, which is known to be reduced in MS, may in part reflect metabolic demand in the neuronal layers of the retina, and could accordingly provide insight regarding concurrent metabolic alterations in the brain.

Objectives

To compare cerebral metabolism in people with MS (PwMS) to healthy controls (HCs) using T2-Relaxation-Under-Spin-Tagging (TRUST) and phase-contrast (PC) MRI, and assess whether cerebral hypometabolism is related to reduced SVP density measured using optical coherence tomography angiography (OCTA).

Methods

In this cross-sectional study, PwMS and HC underwent TRUST and PC MRI to derive the oxygen extraction fraction (OEF; a measure of the efficiency of cerebral tissue in extracting oxygen from circulating blood) and cerebral metabolic rate of oxygen consumption (CMRO2; a volume-adjusted measure of cerebral tissue metabolism). A subset of PwMS underwent OCTA, with quantification of retinal SVP density using a deep neural network based-algorithm. Statistical analyses were adjusted for age and intra-subject inter-eye correlations, where relevant.

Results

We included 49 PwMS and 80 HCs. Overall, OEF was lower, and CMRO2 trended towards being lower, in PwMS as compared to HCs (OEF: 35.9% [SD 5.1] vs. 40.9%, [SD 5.1], p=0.04; CMRO2: 156.3 umol/mL/min [SD 23.9] vs. 158.7 umol/mL/min [SD 19.9], p=0.08). Lower CMRO2 was associated with longer MS disease duration (p=0.02), higher expanded disability status scale score (p=0.01) and lower subcortical gray matter volume fraction (p=0.04). Additionally, lower CMRO2 was associated with higher age in PwMS (p=0.02), but not in HCs (p=0.19), in whom effective neurovascular coupling is expected to maintain a fairly constant rate with aging. Lower OEF correlated with lower retinal SVP density in PwMS (r=0.32, p=0.02).

Conclusions

Cerebral hypometabolism is evident in PwMS compared to HCs, and is associated with longer disease duration and greater disability. Furthermore, alterations in cerebral metabolism are mirrored by alterations in retinal SVP density, supporting the utility of these non-invasive imaging techniques to measure inter-linked pathobiological processes. The ability to detect metabolic dysfunction in-vivo in PwMS may help facilitate the identification of new therapeutic targets and outcome measures for clinical trials.

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Neuromyelitis Optica and Anti-MOG Disease Poster Presentation

P0713 - Evidence of subclinical quantitative retinal layer abnormalities in aquaporin-4-IgG seropositive NMOSD (ID 862)

Speakers
Presentation Number
P0713
Presentation Topic
Neuromyelitis Optica and Anti-MOG Disease

Abstract

Background

Aquaporin-4-IgG (AQP4-IgG) seropositive Neuromyelitis Optica Spectrum Disorder (NMOSD) typically presents with discrete attacks of optic neuritis (ON) and transverse myelitis, and insidious subclinical disease activity is considered a rare occurrence. Prior optical coherence tomography (OCT) studies have suggested that subclinical retinal abnormalities, including lower foveal thickness and altered foveal morphology, may be present in AQP4-IgG+ NMOSD in the absence of a clinical history of ON; however, existing studies were relatively small.

Objectives

To compare retinal layer thicknesses at the fovea and surrounding macula between AQP4-IgG+ NMOSD eyes without a history of ON (AQP4-nonON) and healthy controls (HC).

Methods

In this single-center cross-sectional study, 83 AQP4-nonON and 153 HC eyes were studied with spectral-domain OCT. Statistical analyses were performed with generalized estimating equations (GEE) and were adjusted for age, sex and race.

Results

Total foveal thickness did not differ between AQP4-nonON and HC eyes (-3.55±3.79μm, p=0.35). AQP4-nonON eyes exhibited lower outer nuclear layer (ONL) and inner photoreceptor segment (IS) thickness at the fovea (ONL: -4.01±2.03μm, p=0.049; IS: -0.32±0.14μm, p=0.029) and surrounding macula (ONL: -1.98±0.95μm, p=0.037; IS: -0.16±0.07μm, p=0.023), compared to HC. Macular retinal nerve fiber layer (mRNFL: -1.34±0.51μm, p=0.009) and ganglion cell + inner plexiform layer (GCIPL: -2.44±0.93μm, p=0.009) thicknesses were also lower in AQP4-nonON compared to HC eyes. The magnitude of the estimated differences was similar in sensitivity analyses restricted to AQP4-IgG+ patients who had never experienced ON in either eye (n=33 patients; mRNFL: -1.33±0.60μm, p=0.026; GCIPL: -2.59±1.12μm, p=0.021; macular ONL: -2.01±1.04μm, p=0.052; macular IS: -0.16±0.08μm, p=0.031; foveal ONL: -3.78±2.28μm, p=0.10; foveal IS: -0.28±0.19μm, p=0.14).

Conclusions

AQP4-nonON eyes exhibited evidence of subclinical retinal ganglion cell neuronal and axonal loss, as well as structural evidence of photoreceptor layer involvement. These results remained largely unaltered in analyses limited to patients who had never experienced ON, suggesting that they are likely related to processes that are independent of clinically overt ON attacks. These findings support that subclinical anterior visual pathway involvement may occur in AQP4-IgG+ NMOSD, and may relate to a primary retinal process or subclinical optic neuropathy.

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