Peripapillary hyper-reflective ovoid mass-like structures (PHOMS) in AQP4-IgG-positive neuromyelitis optica spectrum disease (NMOSD) and MOG-IgG-associated disease (MOGAD)

Peripapillary hyperreflective ovoid mass-like structures: multimodal imaging and associated diseases

Growing evidence has demonstrated that peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel structures rather than a subtype of optic disc drusen. They correspond to the laterally bulging herniation of optic nerve fibers and are believed to be the marker of axoplasmic stasis. PHOMS present in a broad spectrum of diseases, including optic disc drusen, tilted disc syndrome, papilloedema, multiple sclerosis, non-arteritic anterior ischemic optic neuropathy, optic neuritis, Leber hereditary optic neuropathy, and so on. We focus on the multimodal imaging features, pathophysiological mechanisms of PHOMS, and their association with multiple diseases and healthy people in this review to deepen the ophthalmologists' understanding of PHOMS. Additionally, we provide some new directions for future research.

Features of Peripapillary Hyperreflective Ovoid Mass-Like Structures in Nonarteritic Anterior Ischemic Optic Neuropathy Patients and Normal Controls

Purpose

To determine the characteristics of peripapillary hyperreflective ovoid mass-like structures (PHOMS) in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and in normal adults.

Methods

A total of 406 included eyes were divided into four groups: acute NAION group, chronic NAION group, unaffected group, and normal eyes group. PHOMS were detected on optical coherence tomography slices from optical coherence tomography angiography scans centered on the optic nerve head (ONH). The differences in age, sex, and ONH parameters were investigated between eyes with PHOMS and eyes without PHOMS among groups.

Results

The prevalence of PHOMS in acute eyes (43.48%) and fellow eyes (28.20%) was significantly higher than that in normal eyes (11.76%) (acute vs. normal, P < 0.001; fellow vs. normal, P = 0.014). In the acute group, the PHOMS score of size was negatively correlated with age in acute eyes (r = -0.486, P = 0.03). The size of PHOMS was negatively correlated with age and cup/disc ratio and positively correlated with retinal nerve fiber layer thickness in the nasal and inferior sectors in the normal groups. No differences in age, sex, ONH parameters, or visual field defects were found between eyes with PHOMS and eyes without PHOMS.

Conclusions

The prevalence of PHOMS increased significantly in acute nonoptic disc drusen (NODD)-NAION eyes and fellow eyes. PHOMS could also be found among normal adults. PHOMS may be a nonspecific sign secondary to ONH edema and axoplasmic stasis.

Translational Relevance

The high prevalence of PHOMS in acute NODD-NAION eyes may indicate axoplasmic stasis secondary to tissue edema.

The Acute Optic Neuritis Network (ACON): Study protocol of a non-interventional prospective multicenter study on diagnosis and treatment of acute optic neuritis

Optic neuritis (ON) often occurs at the presentation of multiple sclerosis (MS), neuromyelitis optica spectrum disorders (NMOSD), and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). The recommended treatment of high-dose corticosteroids for ON is based on a North American study population, which did not address treatment timing or antibody serostatus. The Acute Optic Neuritis Network (ACON) presents a global, prospective, observational study protocol primarily designed to investigate the effect of time to high-dose corticosteroid treatment on 6-month visual outcomes in ON. Patients presenting within 30 days of the inaugural ON will be enrolled. For the primary analysis, patients will subsequently be assigned into the MS-ON group, the aquapotin-4-IgG positive ON (AQP4-IgG+ON) group or the MOG-IgG positive ON (MOG-IgG+ON) group and then further sub-stratified according to the number of days from the onset of visual loss to high-dose corticosteroids (days-to-Rx). The primary outcome measure will be high-contrast best-corrected visual acuity (HC-BCVA) at 6 months. In addition, multimodal data will be collected in subjects with any ON (CIS-ON, MS-ON, AQP4-IgG+ON or MOG-IgG+ON, and seronegative non-MS-ON), excluding infectious and granulomatous ON. Secondary outcomes include low-contrast best-corrected visual acuity (LC-BCVA), optical coherence tomography (OCT), magnetic resonance imaging (MRI) measurements, serum and cerebrospinal fluid (CSF) biomarkers (AQP4-IgG and MOG-IgG levels, neurofilament, and glial fibrillary protein), and patient reported outcome measures (headache, visual function in daily routine, depression, and quality of life questionnaires) at presentation at 6-month and 12-month follow-up visits. Data will be collected from 28 academic hospitals from Africa, Asia, the Middle East, Europe, North America, South America, and Australia. Planned recruitment consists of 100 MS-ON, 50 AQP4-IgG+ON, and 50 MOG-IgG+ON. This prospective, multimodal data collection will assess the potential value of early high-dose corticosteroid treatment, investigate the interrelations between functional impairments and structural changes, and evaluate the diagnostic yield of laboratory biomarkers. This analysis has the ability to substantially improve treatment strategies and the accuracy of diagnostic stratification in acute demyelinating ON.

Trial registration

ClinicalTrials.gov, identifier: NCT05605951.