Table 3.

Magnetic Resonance Imaging Characteristics at ON Onset in Patients with LO-NMOSD-ON and Patients with EO-NMOSD-ON: Segmental Enhancement of AVPs

Segmental Enhancement of AVPs	LO-NMOSD-ON (n = 10 AVPs)	EO-NMOSD-ON (n = 24 AVPs)	p-value
▫ Segmental enhancement of AVPs, n of AVPs with each enhanced segment/n of available AVPs (%)
Orbital optic nerve	8/10 (80.0%)	17/24 (70.8%)	0.69
Intracanalicular optic nerve	6/10 (60.0%)	19/24 (79.1%)	0.39
Intracranial optic nerve	2/10 (20.0%)	13/24 (54.1%)	0.12
Optic chiasm	0/10 (0.0%)	4/24 (16.6%)	0.29
Optic tract	0/10 (0.0%)	1/24 (4.1%)	1.00 0.43
≥2 consecutive enhanced segments	6/10 (60.0%)	18/24 (75.0%)
▫ Total enhanced segments, mean ± standard deviation, segments	1.60 ± 0.51	2.20 ± 1.02	0.08

Abbreviations: LO-NMOSD-ON, late-onset neuromyelitis optica spectrum disorder-related optic neuritis; EO-NMOSD-ON, early-onset neuromyelitis optica spectrum disorder-related optic neuritis; ON, optic neuritis; AVP, anterior visual pathway; n, number.