These procedures go beyond the normal routine eye examination. They will flow from patient age, symptoms and/or signs, predisposing risk factors, or findings during the routine eye examination. Many will be subsequent to the routine examination and some on another day. They all have the potential to assist in accurate diagnosis and patient management. This group includes: various forms of tonometry, various forms of fundus examination and anterior chamber evaluation.
This is a hand held instrument that uses air pressure to applanate the cornea. The Pulsair uses a transducer to directly measure the air pressure at the point at which the cornea is flattened. Firing the demo button once will give a value of 30, firing it twice will give a value of 50 if the mach...
Only when the tonometer is at the correct distance and properly aligned with respect to the patient’s cornea, will the image of the corneal reflex fall onto three photodetectors in such a way that more light falls onto the two outer detectors than the central one. At the moment that the instrumen...
The Goldmann applanation tonometer consists of an applanating probe and weight loaded lever system, which is placed on a slit-lamp mount. The end of the probe is brought into contact with the anaesthetised cornea. When contact is made, the clinician views the applanated area (which is made visibl...
This is a hand held version of the Goldmann tonometer. It uses a spring to exert a variable force upon the eye. It can be used with patients supine or erect. Since it lacks the control and security of a slit-lamp, care must be taken to stabilise the instrument to ensure centration without causing...
This video shows how drugs can be instilled without causing the clinician stress nor the patient anxiety.
This is used to measure intraocular pressure for the detection and management of glaucoma. The end of the probe is brought into contact with the anaesthetised cornea. When contact is made, the clinician views the applanated area (which is made visible by the instillation of fluorescein). The forc...
One of the most important, but often forgotten parts of the visual field analysis is the setting up stage. Inadequate set up of the patient or the instrument or both is the most common cause for artefactual visual field defects.
The amount of fusional vergence that can be exerted to maintain clear and single binocular vision. Components of fusional vergence are: Sensory fusion - the ability to appreciate two similar images, one formed on each retina and interpret them as a single image. Motor fusion - the maintenance of ...
This test consists of a series of plates designed to provide a quick and accurate assessment of colour vision deficiency of congenital origin. Most cases are characterised by a red or green deficiency.
The test comprises selected paper colour samples. On each page, four colour samples surround a central spot and the subject must choose the one that most closely resembles the colour of the central spot. Each page provides possible protan, deutan or tritan confusions that may be mixed with a norm...
The Amsler grid is a test chart used to determine quality of central vision and allows the analysis of disturbances of visual function, which accompany the beginning and evolution of maculopathies. The standard chart to be used in this practical consists of a square with white lines on a black ba...
Children may become frightened as the clinician approaches closely, during direct ophthalmoscopy and co-operation could be lost. Also, children often look at the ophthalmoscope light and track it as the clinician moves, allowing examination of the macula but not the optic disc. Furthermore, the f...
