CRAO is considered a stroke of the eye. Studies show that about two-thirds of patients have underlying high blood pressure and one-fourth of patients will have significant carotid artery disease (plaque with narrowing of the artery lining), cardiac valvular disease or diabetes.
Electrical pressure is measured in volts, or voltage. All electrical devices are rated for specific voltages. Most devices and small appliances in a home are rated for 120 volts, while high-voltage appliances, such as electric dryers, ranges, and many baseboard heaters, are rated for 240 volts.
The bigger the voltage and the bigger the current, the more electrical power you have. We measure electric power in units called watts. Something that uses 1 watt uses 1 joule of energy each second. The electric power in a circuit is equal to the voltage Ã the current (in other words: watts = volts Ã amps). So if you have a 100-watt (100 W) light and you know your electricity supply is rated as 120 volts (typical household voltage in the United States), the current flowing must be 100/120 = 0.8 amps.