Non-neoplastic Pathology of the Uveal Tract
The uveal tract is a highly vascular structure consisting of the iris, ciliary body, and choroid. The uveal tract may be involved by developmental abnormalities, noninfectious and infectious inflammation (uveitis), systemic diseases, vascular disorders, degenerative conditions, and inherited diseases. In this chapter, we provide a brief overview of the normal anatomy of the uveal tract and the clinical, pathological, and pathogenetic features of these entities: 1. Developmental disorders: Persistent pupillary membrane, persistence of the tunica vasculosa lentis, iris cysts, iris hypoplasia and aniridia, and colobomas. 2. Noninfectious uveitis: Sarcoidosis, Blau syndrome, Behçet's disease, sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome, granulomatosis with polyangiitis (Wegener granulomatosis), phacoantigenic uveitis, tissue reactions to artificial intraocular lens implants, autoimmune anterior uveitis, HLA-B27 acute anterior uveitis, juvenile idiopathic arthritis, Fuchs' heterochromic uveitis, tubulointerstitial nephritis and uveitis syndrome, intermediate uveitis, birdshot retinochoroidopathy, acute posterior multifocal placoid pigment epitheliopathy, serpiginous choroiditis, and drug-induced uveitis. 3. Infectious uveitis: Bacterial endophthalmitis, tuberculosis, leprosy, syphilis, Lyme disease, nocardiosis, herpes simplex virus, varicella zoster virus, cytomegalovirus, congenital rubella syndrome, human immunodeficiency virus/acquired immunodeficiency syndrome, Candida albicans, histoplasmosis, cryptococcal choroiditis, Aspergillus species, Pneumocystis jirovecii choroidopathy, toxoplasmosis, toxocariasis, and onchocerciasis. 4. Systemic disease: Diabetes mellitus, neurofibromatosis (Lisch nodules), and cystinosis. 5. Vascular diseases: Malignant hypertension, uveal ischemia and necrosis, rubeosis iridis/iris neovascularization, choroidal neovascularization, and choroidal hemorrhage and effusion. 6. Degenerative conditions: Angioid streaks and iridocorneal endothelial syndrome. 7. Inherited choroidal diseases: Central areolar choroidal dystrophy, North Carolina macular dystrophy, progressive bifocal chorioretinal atrophy, Bietti's crystalline retinopathy, gyrate atrophy, and choroideremia.
