Post-refraction procedures, such as the ophthalmoscopy and Mallett unit testing, are usually performed after the optimum refractive correction has been determined. Some procedures, such as those assessing oculomotor balance, may be conducted pre- and post-refraction to determine if the new refractive correction has had any effect on the results of those tests. Other procedures may be conducted post-refraction in order not to negatively affect the refraction procedures, such as contact tonometry and fundoscopy through dilated pupils.
This is a distortion test whereby a distorted image is presented to one eye to a level were fusion cannot occur. This distortion is produced by grooves (plano-convex cylinders) ground onto a disc of coloured glass – red glass used for distance and green glass used for near. A spotlight seen throu...
The Maddox wing is designed to work at 30cm. The patient looks through two slit holes and the presence of a septa means that separate views are seen by each eye i.e. different targets are presented to each eye so fusion cannot occur. The right eye sees arrows while the left eye sees tangent scale...
People present to optometrists complaining of headache, eye ache, tired and sore eyes, poor concentration and poor performance at school or work. With this clinical scenario many optometrists test for the presence of fixation disparity. The amount of prism required to remove fixation disparity ha...
When evaluating the anterior segment the direct ophthalmoscope is used to assess the external structures, iris and lens, and to identify abnormalities or the need for further investigation. Abnormalities picked up in the anterior segment can be more thoroughly examined using slit-lamp biomicroscopy.
When evaluating the posterior segment the direct ophthalmoscope is used to assess the vitreous, optic disc and retina, and to identify abnormalities or the need for further investigation. Abnormalities picked up in the posterior segment can be more thoroughly examined through dilated pupils using...
Slit-lamp examination of the lids, lashes, conjunctiva, sclera and cornea is important during contact lens fitting and aftercare and for those patients when symptoms or signs suggest the problem may lie with these ocular structures. Diffuse illumination refers to a wide beam that is directed obli...
