Central corneal thickness

Rachymetry measures central corneal thickness thin corneas (less than 540 microns) are considered a glaucoma risk factor. 

T reatment is indicated for ocular hypertension if the patient has a significant risk factor such as IOP greater than 25 mm Hg, vertical cup-disk ratio greater than 0.5, or central corneal thickness less than 555 micrometers. Additional risk factors to be considered include family history of glaucoma, black race, severe myopia, and presence of only one eye. 

Even in the absence of contact lens wear, the central corneal thickness (CCT) undergoes normal dim-nal variation. CCT is thicker when awakening from sleep and decreases exponentially over approximately 2 homs. 

Vertical cupping of the optic nerve head Pattern standard deviation on visual fields Thin central corneal thickness < 555 mcm... 

Aghaian E, Choe JE, Lin S, Stamper RL. Central corneal thickness of Caucasians, Chinese, Hispanics, Filipinos, African American, and Japanese in a glaucoma clinic. Ophthalmology 2004 111 2211-2219. 

Outline the importance of central corneal thickness in glaucoma practice. 

Ehlers N, Bramsen T, Sperling S (1975) Applanation tonometry and central corneal thickness. Acta Ophthalmol (Copenh) 53 1974-1983. 

Similarly, after use in ECCE, many clinical studies revealed insignificant or clinically irrelevant differences in endothelial cell loss and corneal thickness when comparing different viscoelastics. (Alpar, 1985 Alpar et al., 1988 Lane, 1991 Smith 8c Lindstrom, 1991). In a trial led by Pederson (1990), central corneal thickness was statistically significant higher following phacoemulsification and use of HPMC products than Healon . 

A 12-year-old girl took amantadine HCl 100 mg bd for 4 months and developed bilateral blurred vision which progressed. She had corneal edema and the central corneal thicknesses were 851 pm in the right eye and 886 pm in the left eye (reference range 509-613) [278 ]. 

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