The choroid is the most commonly involved site although this is not always clinically apparrent. Ocular and orbital involvement can manifest as skin infiltration, extraocular muscle palsies, diplopia, proptosis, subconjunctival hemorrhage, sterile ring ulcers, anterior segment necrosis, ciliary body involvement, vitreous leukemic infiltrates, retinal hemorrhages, cotton wool spots, serous retinal detachments, RPE changes, papilledema, or optic nerve infiltration. Hyperviscosity states can manifest as retinal microaneurysms, venous occlusive disease, and retinal neovascularization. Opportunistic infections are common. Complications of therapy include radiation or steroid related cataracts, radiation retinopathy, and chemotherapeutic agent side effects.
Symptoms can include redness, photophobia, changes in pupil shape or color, pain, and visual loss.
Clinically, anterior segment leukemic infiltrates can be distinguished from anterior uveitis in that leukemic involvement presents more commonly with normal or slightly decreased pupil size, segmental or total ciliary injection, segmental or diffuse iris swelling, hypopyon and hyphema, increased intraocular pressure, and rarely with posterior synechiae. Anterior uveitis tends to present with miotic pupils, total ciliary injection, flat irides, low intraocular pressures, posterior synechiae, and less commonly with hypopyon or hyphema. References Schachat AP, Markowitz JA, Guyer DR, et al. MacLean H, Clarke MP, Strong NP, et al. Primary Ocular Relapse in Acute Lymphoblastic Leukemia.