● Tear film assessment should be undertaken with minimal invasion of the structure – non-invasive techniques should be used whenever possible ● Assessment must be made both prior to and during contact lens wear. Tear film quality should be assessed both with the lens in situ and without the lens ● Use of the Tearscope in clinical practice allows a more detailed examination of the tears to be un...

A chemiluminescence (CL) method has been developed for the determination of Hydroxyzine (Hyd) and its metabolite Cetirizine (Cet). The method is based on sensitizing effect of Cet and Hyd on the weak CL reaction between Ru(phen)32+ and acidic Ce(IV). A mechanism for the CL reaction has been proposed on the basis of UV-Vis, fluorescent and CL spectra. By using the recommended procedure, the cali...

A n active ciliary body controls the eye’s accommodation process, allowing near focusing to occur. The ciliary body is made up mainly of smooth muscle, known as the ciliary muscle. Accommodation occurs when the muscarinic receptors within the ciliary muscle are stimulated by the parasympathetic neurotransmitter, acetylcholine (see Part 1 Optician 29.06.12). The ciliary muscle then contracts, pu...

M acular oedema refers to the accumulation of fluid in retinal layers around the fovea, usually as a result of blood-retina barrier dysfunction. Macular oedema is not a specific entity, but rather a non-specific response to an abnormal retinal environment. Vision is impaired due to disruption of the normal cellular relationships in the retina, mechanical stress, and a mild inflammatory response...

In the last in our three-part series on myopia, Catherine Viner considers the assessment and correction of myopia in practice. Module C15569, one general point for optometrists and DOs Part 3: Assessment and correction T he predominant symptom in uncorrected (or undercorrected) myopia is blurred distance vision.1-3 It is suggested that because this symptom is so readily apparent, myopes account...