If all the isopters show similar depression to the same point, it is then called a contraction of visual field. Relative paracentral scotomas are the areas where smaller and dimmer targets are not visualized by the patient. Larger and brighter targets can be seen. Small paracentral depressions, mainly superonasal are seen in normal tension glaucoma (NTG). The generalized depression of the entire field may be seen in cataract also. Baring of blind spot: "Baring of blind spot" means exclusion of blind spot from the central field due to inward curve of the outer boundary of 30° central field. It is only an early non-specific visual field change, without much diagnostic value in glaucoma. Small wing-shaped Paracentral scotoma: Small wing-shaped Paracentral scotoma within Bjerrums area is the earliest clinically significant field defect seen in glaucoma. It may also be associated with nasal steps. Scotoma may be seen above or below the blind spot. Siedels sickle-shaped scotoma: Paracentral scotoma joins with the blind spot to form the Seidel sign. Arcuate or Bjerrums scotoma:  It is formed at later stages of glaucoma by extension of Seidels scotoma in an area either above or below the fixation point to reach the horizontal line. Peripheral breakthrough may occur due to damage of nerve fibers. Ring or Double arcuate scotoma: Two arcuate scotomas join to form a Ring or Double arcuate scotoma. This defect is seen in advanced stages of glaucoma.
Atenolol/chlorthalidone, also known as co-tenidone, is a combination medication used to treat high blood pressure. It is made up of atenolol, a beta-blocker and chlortalidone, a diuretic. It is not recommended as an initial treatment but may be used in those who are taking atenolol and chlortalidone individually. It is taken by mouth.Common side effects include gastrointestinal upset and gout. Serious side effects may include liver problems, pancreatitis, and psychosis. Use is not recommended during pregnancy. Use during breastfeeding may harm the baby. Atenolol works by blocking β1-adrenergic receptors in the heart, thus decreasing the heart rate and workload. Chlorthalidone works by increasing the amount of sodium lost by the kidneys.The combination was approved for medical use in the United States in 1984. It is available as a generic medication. In 2017, it was the 295th most commonly prescribed medication in the United States, with more than one million prescriptions. References
External links
"Atenolol mixture with chlorthalidone". Drug Information Portal. U.S. National Library of Medicine.