Optic disk edema with a macular star.

Optic disk edema with a macular star is a descriptive term encompassing a heterogeneous group of disorders. The clinical features include sudden visual loss, swelling of the optic disk, peripapillary and macular exudates that may occur in a star pattern, and cells in the vitreous. Herein we describe the clinical features, potential etiologic factors, differential diagnosis, work-up, and natural history of this entity. Although optic disk edema with a macular star is usually idiopathic, infectious causes, especially syphilis, Lyme disease, cat-scratch disease, and toxoplasmosis, should be considered. The macular exudate likely results from primary optic nerve disease, not from inflammation of the retina; therefore, we prefer the term "idiopathic optic disk edema with a macular star" for idiopathic cases rather than "neuroretinitis." When optic disk swelling and macular star are associated with focal or multifocal inflammatory lesions in the retina (retinitis), especially if an infectious cause is documented, the term "neuroretinitis" is appropriate. The prognosis for visual recovery is usually good, but residual visual loss may be severe in a few cases. Patients with a recurrent type of the disease may not experience pronounced improvement in optic nerve function. The macular exudate may not develop in cases of disk edema until 2 weeks after the patient's initial assessment; thus, patients who have acute papillitis with a normal macula should be reexamined within 2 weeks for development of a macular star. The presence of a macular star militates strongly against subsequent development of multiple sclerosis.