Acute angle-closure glaucoma

Primary open-angle glaucoma is a chronic, usually asymptomatic optic neuropathy with a normal iridocorneal angle, progressive cupping of the optic disc, and characteristic peripheral-before-central visual field loss. Diagnosis rests on tonometry, gonioscopy to confirm the open angle, dilated funduscopy with cup-disc ratio, and perimetry, and treatment is lifelong topical IOP-lowering therapy escalating to laser or incisional surgery for uncontrolled disease.

Uveitis is inflammation of the uveal tract, classified by anatomic location as anterior, intermediate, posterior, or panuveitis and by systemic association such as HLA-B27 spondyloarthritis, sarcoidosis, or Behcet disease. Anterior uveitis presents with a painful red eye and photophobia diagnosed at the slit lamp, while posterior uveitis presents with painless floaters or vision loss, and treatment is topical corticosteroid for anterior disease escalating to systemic corticosteroid and steroid-sparing immunosuppression for recurrent, severe, or posterior-segment disease.

A corneal abrasion is a traumatic or foreign-body-related defect of the corneal epithelium diagnosed by fluorescein uptake under cobalt-blue light. Uncomplicated cases heal in days with lubrication and pain control, but contact-lens wear mandates antipseudomonal coverage and any red flag (rust ring, infiltrate, Seidel sign, hypopyon) demands same-day ophthalmology referral.

Conjunctivitis is inflammation of the conjunctiva from viral, bacterial, or allergic causes presenting with red eye, discharge, and preserved vision, diagnosed clinically by discharge character and managed with supportive care, targeted topical antibiotics, or topical antihistamine/mast-cell-stabilizer therapy.

Giant cell arteritis is a granulomatous large- and medium-vessel vasculitis of patients over 50 that threatens irreversible blindness through ischemic optic neuropathy. Diagnosis is clinical and must not delay treatment: start high-dose glucocorticoids immediately on suspicion, intravenous methylprednisolone pulse for visual loss, then confirm with temporal artery biopsy within 1 to 2 weeks and add tocilizumab as glucocorticoid-sparing therapy.

Central retinal artery occlusion is sudden, painless, profound monocular vision loss from embolic or thrombotic occlusion of the central retinal artery, an ocular stroke equivalent in which irreversible retinal infarction begins around 90 minutes after complete occlusion. Diagnosis is clinical on dilated fundoscopy, and management pairs time-critical reperfusion attempts with an emergency embolic and giant-cell-arteritis workup to protect the fellow eye and prevent a subsequent stroke.

Optic neuritis is inflammatory demyelination of the optic nerve, usually a presenting event of multiple sclerosis, causing subacute painful monocular vision loss with a relative afferent pupillary defect. Confirm with MRI orbits/brain and treat with IV methylprednisolone followed by an oral prednisone taper, never oral prednisone alone.

Cluster headache is a trigeminal autonomic cephalalgia causing severe unilateral orbital or temporal pain lasting 15 to 180 minutes, up to eight times daily, with ipsilateral autonomic features. First-line acute treatment is 100% oxygen inhalation or subcutaneous sumatriptan; verapamil is first-line prevention.

Migraine is a primary episodic headache disorder diagnosed by ICHD-3 clinical criteria (recurrent attacks, 4-72 hours, pulsatile/unilateral pain with nausea or photophobia/phonophobia). First-line acute treatment is an NSAID or oral triptan started early in the attack; prevention with a beta-blocker, topiramate, or CGRP-targeted therapy is added once attacks are frequent or disabling.