Final answer:
ICD-10 irregular astigmatism unspecified is a diagnostic code for a common vision condition where the cornea or lens has an uneven curvature, leading to distorted vision. Cylindrical correction is used in eyeglasses to correct this irregularity, and a special chart can help detect the presence of astigmatism.
Step-by-step explanation:
The term ICD-10 irregular astigmatism unspecified refers to a diagnosis code used in the International Classification of Diseases, Tenth Revision (ICD-10), to categorize health disorders. Astigmatism itself is an eye condition characterized by an uneven curvature of the cornea or lens, causing blurred or distorted vision.
It is a common vision defect where rays of light passing through different regions of the eye focus at various points, leading to images appearing elongated or less distinct. Cylindrical correction in eyeglasses addresses the irregularity in astigmatism by offsetting the unevenness in the eye's focus, whereas spherical corrections are used for short- or farsightedness and are the same along all axes. A chart, like the one mentioned as Figure 26.8, helps in detecting astigmatism by revealing the difference in image clarity along different axes to the examined eye.