Peripartum Decompensation of an Orbital Vascular Malformation Managed With Urgent Postpartum Surgical Decompression.

A 36-year-old woman at 36 weeks gestation presented with 5 months of pain on upgaze and 2 months of progressive vision loss in the right eye. Examination revealed 20/200 acuity, a relative afferent pupillary defect, proptosis, motility restriction, disc edema, and visual field loss. Noncontrast MRI showed a lobulated superolateral orbital apex mass, with differential diagnosis including an orbital vascular malformation enlarged by gestational hypervolemia versus a hormonally sensitive meningioma. Given severe vision loss and advanced gestational age, induced delivery was performed. Postpartum imaging and rapid partial visual recovery favored a vascular etiology. Because spontaneous resolution could not be reliably timed to prevent permanent damage, endoscopic transethmoidal posterior medial wall decompression was performed, restoring vision to 20/20-1 with subsequent lesion regression and normalization of examination findings by 4 months postpartum. Coordinated obstetric-ophthalmic management achieved excellent maternal and fetal outcomes.