Glaucoma ducts, and narrowing or closure of the angle between the iris and cornea. The primary division in categorizing different types of glaucoma is open-angle and closed-angle (or angle-closure) glaucoma. In open angle glaucoma, the iris meets the cornea normally, allowing the fluid from inside the eye to drain, thus relieving the internal pressure. Where this angle is narrowed or closed, pressure increases over time, causing damage to the optic nerve, leading to blindness. Primary open-angle glaucoma (also, "primary glaucoma", "chronic glaucoma") refers to slow clogging of the drainage canals resulting in increased eye pressure which causes progressive optic nerve damage.
Henneke horse body condition scoring system Cup (a 160-km / 100-mile 24-hour race held each August near Truckee, California) found both for 1995 and 1996 (study 1) and for 1998 (study 2), that significantly more horses finished the race when they had a higher (vs. lower) body condition score: Horses competing in 1995 and 1996 had body condition scores ranging from 1.5 to 5.5 (1998: 2.5 to 5.5); no horses with a score of ≤ 2.5 (1998: scores ≤ 3) finished the respective race, and all horses with a score of 5.5 (same in 1998) finished the respective race. In both studies, no significant relationship was