Trifocal & progressive large intermediate zone computer progessive and Trifocals Baba 1 *,Rathna Kumar 2, 1 Professor,2 Associte Professor,Department of Ophthalmology Sri Lakshmi Narayana Institute of Medical Sciences (Affiliated to Bharath University,Chennai), Osudu, Puducherry, *Corresponding Author Dr.Baba Dept. of Ophthalmology, Sri Lakshmi Narayana Institute of Medical Sciences, (Affiliated to Bharath University,Chennai), Osudu, Puducherry,Puducherry -605 502, India. E.Mail: slimspub@yahoo.in
INTRODUCTION C.V.S. is a condition seen after prolonged work at computer precipitated by wrong ergonomic and/or faulty eye condition resulting in eye as well as general problems. Incidence In USA alone, 143 million adults and 53 million children use computers on a day to day basis. Out of these 88% i.e. approx 176million havebeen associated with eye strain. This leads to a hefty financial loss. And the employees are to be taken care of for their eye defects (Jalinderbali et al. 2007) Features The features of CVS can be classified into two types mainly. They are as follows: 1. Ocular 2. General Ocular The ocular features often complained by the patients are as follows: 1. Blurred or double vision 2. Inability to focus at distance 3. Irritation & watering 4. Eye fatigue. 5. Burning of eyes 6. Excess tearing 7. Dry eye 8. Frequent blinking These features have a lasting effect on the vision and eyes.
General Along with the expected and usual eye symptoms mentioned above patients also do come with general complaints as given below 1. Head ache 2. Pain over neck and back 3. Psychological Causes The main cause of the CVS syndrome is found to be the Computer fonts. The fonts have no sharp edges and the contrast is less andalong with that the color intensity at edge is less. All these factors lead to a constant refocusing of the eyes during vision. This causes different reactions by the eye and the brain while focussing on the screen (Clayton blehm et al., 2005). The computer screen made available in the markets is devoid of any form of harmful waves that could cause the CVS symptoms. METHODOLOGY Various computer centers in the nearby locality where chosen and professional computerists were taken as the study subjects. Their individual ergonomics were checked on the spot and any symptoms complained were recorded. Later anterior segment was studied and their visual acuity was checked. The accommodation and convergence was also measured (RAF scale).some individuals were identified and categorized for detailed study (Biljana et al., 2007).
RESULTS 45 persons were assessed. This included 21 gents and 24 ladies. All people belonged between 20 and 30 yrs of age. Among them 6 people had positive symptoms, two people had normal vision despite of their symptoms and four people had minimal error and was corrected. There were 39 people who were symptomless with a minimal error in 11 of them. But they didn t report any complaints. OPHTHALMIC MANAGEMENT The usual near vision. glasses are of no use and the routine progressive and trifocal lenses are also useless because intermediate zone is small computer glasses a) single vison adjust for screen distance (lens ) b) trifocal & progressive large intermediate zone computer progessive and Trifocals - unfit for usual distance vision less bv zone frame - any model. REFERENCES Jalinderbali, Neernavin and Bali renuthaker (2007). computer vision syndrome: A study of the knowledge, attitudes and practices in Indian opthamologists, Indian journal of opthamology 55(4) 289-293. Clayton blehm, seema Vishnu and ashbalakhatlak, (2005). computer vision syndrome; a review survey of ophthalmology 50(3) 253-262.
Ysun and Fisher (2003). Elsevier object-based visual attention for computer vision,artificial intelligence in science direct 46(1) Biljana Miljanovic and RezaDana (2007) impact of dry eye syndrome on vision march 2007- related quality of life, American journal of ophthalmology 43(3) 409-415.