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LETTER TO EDITOR |
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Year : 1999 | Volume
: 47
| Issue : 4 | Page : 265-266 |
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Strategies for correcting surgical aphakia
NV Prajna, G Venkataswamy
Correspondence Address: N V Prajna
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 10892489 
How to cite this article: Prajna N V, Venkataswamy G. Strategies for correcting surgical aphakia. Indian J Ophthalmol 1999;47:265-6 |
Dear Editor: | |  |
A recent clinical trial conducted in India evaluated the safety and efficacy of extracapsular cataract extraction with posterior chamber intraocular lens (ECCE/PCIOL) compared to intracapsular cataract extraction with aphakic glasses (ICCE/AG).[1] The most noteworthy result of this study was a comparison of the postoperative visual acuity at 12 months within the ICCE/AG group depending on the correction used. With regard to the ICCE/AG group, visual acuity ≥ 6/ 12 was present in 33% of patients when corrected with a standard +10 D lens, while a careful manifest refraction with both sphere and cylinder improved the percentage to 90%. However, just fitting the spherical equivalent to the aphakic patient improved the vision to ≥ 6/12 in 87% of cases. This compared quite favorably to the ECCE/PCIOL group without correction having 64% with vision ≥ 6/12 and with best manifest correction having 96% with vision ≥ 6/12. The clear conclusion from this data was that fitting a spherical correction rather than only a + 10 D lens improves aphakic vision immensely.
Why are these data so important? It is a fact that although the demand for ECCE/PCIOL is increasing in India, a significant proportion of cataract operations at the present time and in the next 5 years or so will continue to be the ICCE/AG procedure. Let us examine why this is so. At present, the Indian Government has crossed the half-way mark in the World Bank Assisted Cataract Blindness Control Project. This program aims to reduce the prevalence of blindness by the turn of the century. This will be accomplished by performing 11.03 million sight restoring cataract operations in the states of Madhya Pradesh, Uttara Pradesh, Andhra Pradesh, Rajasthan, Tamil Nadu, Orissa, and Maharashtra during the 7-year project (1994-2001). Although there is no doubt that substantial resources are being expended to train surgeons in ECCE/PCIOL, it is only slowly replacing the ICCE/AG procedure. For additional data on how rapidly ECCE/PCIOL is replacing ICCE/AG, we can turn to the two surveys of Indian ophthalmologists who are members of the All India Ophthalmological Society, conducted in 1992 and repeated in 1995. [2, 3] In 1992, 26% of private patients received an ECCE/PCIOL. Among patients operated in Government facilities (one third of the annual national data), 9% received an ECCE/PCIOL. By 1995, the private sector had increased the ECCE/PCIOL to 43% and the government sector increased ECCE/PCIOL to 31%. Thus 52% of private cases and 67% of patients seen in government facilities were still receiving either ICCE/AG or ECCE/PCIOL. The change to ECCE/ PCIOL is taking place slowly but the majority of cases still require aphakic glasses.
The National Program for the Control of Blindness (NPCB) reported that between 1995 and 1996, a total of 2,469,000 cataract operations were performed. If it is assumed that two-thirds of these patients (1,613,000) were operated in private facilities and approximately 50% (806,500) needed aphakic correction and one-third of these patients (823,000) were operated in government facilities and approximately 65% (534,950) needed aphakic correction, then a total of about 1,341,550 patients would receive either no aphakic correction or merely a +10 D lens. Since the goal of the NPCB is sight restoration, we return to the question of aphakic correction. If one uses the percentage of patients better than 6/12 vision, there is good agreement between the best manifest correction (90.7%) and use of the spherical equivalent (87.4%) as compared to using a +10 D lens (33%). The table presents the distribution of spherical equivalent correction resulting in a visual acuity of 6/ 12 or better. Of the 1224 patients in whom a spherical equivalent lens resulted in visual acuity 6/12 or better, 5 spherical lens in one-half diopter steps from + 10 D to + 12 D accounted for 89% of the 6/12 or better vision (Table).
There is no doubt that Indian ophthalmologists are moving toward PCIOL following cataract extraction.[4] However, it is imperative that training takes place, equipment made be available and the cost is within the reach of the vast majority of those who need cataract surgery. This "evolution" in cataract surgery will certainly progress by the start of the twenty first century and will bring about a marked improvement in the quality of life of the Indian people. Meanwhile every effort should be made to adequately rehabilitate the aphakic person so that he becomes a "satisfied customer".
References | |  |
1. | Prajna NV, Chandrakanth KS, Kim R, Narendran V, Selvakumar S, Raohini G, et al. The Madurai intraocular lens study II. Clinical outcomes. Am J Ophthalmol 1998;125:14-25. |
2. | Gupta AK, Ellwein LB. The pattern of cataract surgery in India: 1992. Indian J Ophthalmol 1995;43:3-8.  [ PUBMED] |
3. | Gupta AK, Tewari HK, Ellwein LB. Cataract surgery in India:Results of a 1995 survey of ophthalmologists. Indian J Ophthalmol 1998;46:47-50.  [ PUBMED] |
4. | Prajna NV, Rahmatulla R. Changing trends in the intraocular lens acceptance in rural Tamil Nadu. Indian J Ophthalmol 1995;43:177-79. |
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