nonglaucomatous

Nonglaucomatous is an ophthalmology and neurology term used to describe conditions affecting the optic nerve or vision that are not caused by glaucoma. It is employed to distinguish optic neuropathies from glaucomatous optic neuropathy, which is linked to elevated intraocular pressure and characteristic cupping of the optic nerve head and progressive peripheral vision loss.

Common nonglaucomatous etiologies include inflammatory optic neuritis, often associated with demyelinating disease; ischemic optic neuropathies, such as anterior ischemic optic neuropathy; compressive optic neuropathies from tumors or mass lesions; hereditary optic neuropathies like Leber hereditary optic neuropathy and dominant optic atrophy; nutritional and toxic optic neuropathies from deficiencies or exposures (for example vitamins B12 or thiamine deficiency, methanol, ethambutol); traumatic optic neuropathy; and infiltrative or inflammatory conditions such as sarcoidosis. While these conditions differ in cause, they may share features such as sudden or subacute vision loss, color vision deficit, and relative afferent pupillary defect, with variable fundus findings ranging from optic disc edema to pallor.

Diagnosis relies on clinical history and ophthalmic examination, supported by visual field testing and optical coherence tomography to assess nerve fiber layer, as well as imaging like MRI to evaluate for compressive lesions. Laboratory tests and genetic testing may be indicated to identify nutritional deficiencies, inflammatory or autoimmune processes, or hereditary etiologies.

Management focuses on treating the underlying cause and preserving vision. This may include immunomodulatory therapy for optic neuritis, address of nutritional deficiencies, management of vascular risk factors, or surgical removal or treatment of compressive lesions. Prognosis varies by disorder and timeliness of diagnosis and treatment. See also glaucoma and optic neuropathies.