Headache, usually unilateral, caused by acute narrow-angle glaucoma and associated with other symptoms and clinical signs of this disorder.
A. Any headache fulfilling criterion C
B. Acute narrow-angle glaucoma has been diagnosed
C. Evidence of causation demonstrated by at least two of the following:
1. headache has developed in temporal relation to the onset of glaucoma
2. headache has significantly worsened in parallel with progression of glaucoma
3. headache has significantly improved or resolved in parallel with improvement in or resolution of glaucoma
4. pain location includes the affected eye
D. Not better accounted for by another ICHD-3 diagnosis.
Acute glaucoma generally causes eye and/or periorbital pain, visual acuity loss (blurring), nausea and vomiting. When intraocular pressure rises above 30 mm Hg, the risk of permanent visual loss rises dramatically, which makes early diagnosis essential.