The posterior staphyloma of pathologic myopia.

A total of 250 myopic patients with posterior staphyloma affecting one or both eyes received a complete ocular examination including binocular indirect ophthalmoscopy, refraction, and axial length measurement. Ten types of staphyloma were noted; five primary and five compound. The primary staphyloma involved the posterior pole (Type I), macular area (Type II), peripapillary area (Type III), the fundus nasal to the disc (Type IV) and the area below the disc (Type V). Compound staphylomas consisted of combined primary staphylomas or distinctive and complex variations of a primary staphyloma, usually Type I. This type also was found to have the greatest prevalence of all ten types. Patients in this group had a 19% incidence of legal blindness with 34.5% of staphylomatous eyes having a vision of 20/200 or less. A remarkably wide range of refractions and axial lengths were found for each staphyloma type. These results indicate the importance of the staphyloma in the diagnosis and prognosis of pathologic myopia. It also offers an improved basis for genetic studies of this disease.