Ophthalmic Equipment

Correcting Vision

admin — Tue, 22 Sep 2009 02:29:07 +0000

Eye disorders are problems with visual acuity that can be corrected with the use of eye glasses or contact lenses. Not to be confused with eye diseases like cataracts and glaucoma, eye disorders happen when the eyes of a person have trouble focusing light rays through the cornea to the retina, which results to blurred vision. Refractive errors can be measured using an ophthalmic instrument called an autorefractor or a phoropter, from which data the optometrist or optician would give a prescription for corrective lenses that would allow the patient their best visual acuity. These types of ophthalmic equipment are found in most any modern optician’s clinic. (more…)

Extemporaneous Eye Examinations: Using the Focometer

admin — Thu, 19 Mar 2009 01:48:40 +0000

Refractive errors happen when the cornea of the eye is shaped differently from the normal circular form and cannot receive light rays properly. Vision errors include myopia or near-sightedness, hyperopia or far-sightedness and astigmatism, all of which can be treated by using prescription eye glasses, contact lenses or in some cases, eye surgery like LASIK or PRK. What corrective lenses do is compensate for the errors in the cornea so that light rays focus onto the retina and not in front as with myopia, or behind as with hyperopia. Refractive eye surgery entails the use of a laser to adjust the cornea, allowing light rays to enter the eye properly. (more…)

Tonometry: Measuring the Pressure in the Eyes

admin — Wed, 11 Mar 2009 08:10:00 +0000

Tonometry is a kind of eye examination where a part of the cornea is observed to measure the pressure of fluid inside the eye. Tonometry is also called intraocular pressure (IOP) measurement or even a glaucoma test because it is usually done to detect glaucoma and begin preventive treatment before it results to blindness. Glaucoma is the third leading cause of blindness globally. Often called the ‘sneak thief of sight’, this kind of visual defect does not have visible symptoms and can only be detected through ophthalmic eye examinations by the proper ophthalmic equipment. Caused by an increased pressure of the fluid in the eyes, glaucoma is an eye disease where optic nerves get damaged and result in permanent loss of vision. There are medications already available to lower intraocular pressure, but there is no cure for glaucoma as of yet. The early detection of this eye disease allows for careful preventive treatment to prevent actual loss of vision. Glaucoma may result from some systemic medications and even from other eye diseases like uveitis. Open angle glaucoma also runs in families. People who might have a high risk of this eye condition are recommended to have regular eye examination to be able to prevent or manage glaucoma in its early stage as soon as possible. (more…)

Looking at the Pupil of the Eye: the Pupilometers

admin — Wed, 11 Mar 2009 08:07:12 +0000

The pupilometer is actually two different opthalmic equipment devices that share the same name. One of the instruments measures the distance between each pupil of the eyes and the other is one that measures the response of the pupil to any kind of visual stimuli. The normal usage of pupilometer is pertaining to the ophthalmic equipment used by optometrists or ophthalmologists to measure inter pupillary distance (PD). This is done in order to fit a person for eyeglasses so that the lenses are focused correctly in the frame. This will ensure that the glasses are positioned directly in front of the visual axis. Measuring for PD is done twice, one with the eyes focusing on a target that is far away from the patient and another one with the patient looking at a closer object. Measurements from the latter are helpful in making reading glasses. While measuring for PD can be done with a ruler using millimetres, the results may not be as accurate as it were done properly with an ophthalmic equipment called the pupilometer. (more…)

Pachymeter: Measuring the Thickness of the Cornea

admin — Wed, 11 Mar 2009 08:04:17 +0000

Pachymeter is a type of ophthalmic equipment that ophthalmologists or optometrists use to measure corneal thickness. Pachymetry is especially helpful to eye surgeons prior to ocular surgery using the ophthalmic surgical microscope, since it is important for them to see the cornea and the exact location in the eye where the adjustments should be made before they properly continue with the surgical operation. Other eye diseases that could be diagnosed using ophthalmic equipment like the pachymeter are glaucoma and even keratoconus, both of which could result to serious visual impairment if not detected and treated early.

Former types of pachymeter equipment used optical principles in measuring the thickness of the cornea. But much has been done to improve the technology behind the pachymeter and contemporary models of this ophthalmic equipment now use the same principles as that of ultrasound with the results appearing in numerical form and analyzed by the ophthalmologist. The latest types of pachymeter instruments now use a procedure concerning Corneal Waveform (CWF). This echogram of the cornea can even be superimposed over another waveform in order for the ophthalmologist to compare the progression of any kind of refractive error or disease and how it reacts to treatment. The technique is similar to a computerized corneal topography, which results in a detailed map of the corneal surface and its curvatures. (more…)