|Year : 1983 | Volume
| Issue : 7 | Page : 995-996
Intraocular lens implant
SM Sathe, Vachrajani
Municipal Eye Hospital, Trimbak, Parshuram Street, Mumbai, India
S M Sathe
Municipal Eye Hospital, Trimbak Parshuram Street, Mumbai
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sathe S M, Vachrajani. Intraocular lens implant. Indian J Ophthalmol 1983;31, Suppl S1:995-6
At the Municipal Eye Hospital for over a period of 6½ years, 100 cases of two loop iridocapsular lens implants (Indian) were done after extracapsular cataract extraction with encouraging results.
| Material and methods|| |
The cases selected were of two categories viz. 1) Unilateral cataracts both traumatic and senile in the younger age group. 2) Bilateral cataracts over the age of 50 years. Out of 41 unilateral cataracts 26 were traumatic and 15 were senile cataracts.
The lens implant was modified to overcome some of the initial problems encountred during the study. The changes were as follows:
Size: Initial total length of the implant was 11 mm. This was reduced to 8.5 mm. after trying out various sizes.
Shape: Biconvex implants were replaced by planoconvex type.
The disc material was polymethylmethacrylate, but the loop material was changed from platinium iridium to prolene as it was found that the metal loops were responsible for changes in the iris viz. depigmentation.
Loop Angle: Varied from 5°-16°.
Power: The diopteric value was equivalent to +10D in spectacle. Later it was changed to +12D as it required lesser correction after the operation.
Sterilization: Initially chemical process (10% NaOH) was used. At present ethylene oxide gas sterilization is used.
Operative Procedure: In all cases lens implants were done as a primary procedure after extracapsular cataract extraction.
a) Open Technique: In this method the cornea is lifted up and the lower loop is inserted in the capsular bag. Then the upper loop is manoeuvred by lifting the iris tissue.
b) Closed Method: The implant is introduced under an air bubble in the anterior chamber.
Post operative follow up: The cases were followed up for a varying period of 3 months to 6 years. Fusion and stereopsis was checked in unilateral cataracts in addition to routine examination.
Complications: Striate Keratitis and mild iridocyclitis responded to routine therapy. In the initial stages iris pigment disturbance noted and was probably due to the metal loops. Out of cases 8 implants were removed because of severe iridocyclitis (6), and dislocation of implants (2).
In 14 cases needling had to be done to improve the vision. In 4 cases antiglaucoma surgery was performed to control the tension.
| Observations|| |
Initial cases in whom implant of power equivalent to +10D spectacle correction was used, required correction upto +1D to +4D spheres and +0.5 cyl to +2.50 cyl. Hence the power of the implant was increased upto +140. Then the patients needed -10D to -3D spherical correction. Now with an implant of +12D sphere the correction required is minimum. The visual acuity of 8 patients in whom implants were removed was 6/60 to 6/24 with glasses.
With the advent of ultrasound appliance the exact dioptric power of implant required can be calculated without difficulty.
Conclusion: With proper selection of cases, lens implant restores almost normal vision. The quality of vision is far superior to aphakic vision with thick glasses. Predicting the future is notoriously hazardous, but looking at the results and the tolerance of the implant, intraocular lens is a great achievement and it will be preferred at least in selected cases till such time as a more physiological contact lens is developed.
[Table - 1], [Table - 2], [Table - 3]