Diagnostic Tests


Ocular ultrasound is a form of testing employing high-frequency sound waves to create an image of some portion of the eye. It is performed in the ophthalmologist's office. After anesthetic drops are applied to the eye, the doctor will position the ultrasound wand so it is touching the eye. The ultrasound will generally be completed in 15 minutes and patients do not experience any pain.

A-scan is an ocular ultrasound that provides information on the length of an eye, which is an important factor in determining the selection of an intraocular lens after cataract removal. An A-scan may also be used to diagnose a variety of common eye conditions as well as analyze the shape and size of a mass within the eye.

IOL Master

The Zeiss IOL Master® is a high-precision measurement tool that is used to measure the axis length, corneal curvature and the anterior chamber depth of the eye. The measurements obtained provide physicians with the information needed in the selection of the right IOL to be used for the patient undergoing cataract surgery.

Approved by the FDA in 2000, the Zeiss IOL Master has proven to be five times more accurate than traditional IOL-fitting technologies. The IOL Master takes less time than an ultrasound, the traditional form of measurment which requires the use of anesthesia. The IOL Master does not come in contact with the patient's eye so there is no need for anesthetic eye drops.


A corneal pachymetry is a diagnostic test that is performed to determine the thickness of the cornea. After anesthetic eye drops are applied, the doctor will place the tip of the pachymeter on the front of the eye.

If the cornea is particularly thin, an intraocular pressure reading may be inaccurately low, and if the cornea is particularly thick, it may result in a reading that is inaccurately high. This knowledge allows the doctor to make adjustments to the pressure reading. A finding of a thin cornea may also indicate an increased risk for the development of glaucoma.

Wavefront Corneal Topography

The cornea is the clear covering of the front of the eye that bends, or refracts, light rays as they enter the eye. For clear vision to occur, the cornea must have the correct shape and clarity to focus incoming light rays precisely on the retina at the back of the eye.

A computerized test called corneal topography can map out the surface of the cornea, alerting your doctor to the presence of inflammation, scarring or astigmatism. It provides information about the surface power, thickness and shape of the cornea, allowing certain corneal diseases or abnormalities to be diagnosed at a much earlier stage than usual. Corneal topography is a valuable tool prior to a contact lens fitting, vision correction procedure or corneal transplant.


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