|Year : 1971 | Volume
| Issue : 4 | Page : 166-168
Ocular changes following cataract extraction : Effect on ocular rigidity
K Nath, RL Vaid
Aligarh Muslim University Institute of Ophthalmology and Jawaharlal Nehru Medical. College, Aligarh, India
Aligarh Muslim University Institute of Ophthalmology and Jawaharlal Nehru Medical. College, Aligarh
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Nath K, Vaid R L. Ocular changes following cataract extraction : Effect on ocular rigidity. Indian J Ophthalmol 1971;19:166-8
|How to cite this URL:|
Nath K, Vaid R L. Ocular changes following cataract extraction : Effect on ocular rigidity. Indian J Ophthalmol [serial online] 1971 [cited 2020 May 28];19:166-8. Available from: http://www.ijo.in/text.asp?1971/19/4/166/35008
Dreager  and Gloster  reported a decrease in ocular rigidity after glaucoma operations, particularly cyclo-diathermy. Yunossada  and Miller, KeskY and Becker  , after a study of 85 cases and 20 cases respectively observed that ocular rigidity was not significantly affected following cataract surgery. The present study was undertaken to assess the effect of uncomplicated cataract extraction on the ocular rigidity.
| Material and Method|| |
33 cases of uncomplicated senile cataracts, including the present study, were screened to rule out the possibility of any other concurrent ocular disease. Ocular rigidity was graphically determined by the friedenwal (1955) nomogram. The intra-ocular pressure was recorded, both by applanation and electronic Schiotz (5.5 gm.) tonometer. Applanation pressure was marked on the ordinate and the electronic Schiotz reading on 5.5 gm. line of the nomogram. These readings were joined by a straight line. Another line, parallel to the above line, was drawn passing through the intercept of the ordinate and the absissa. The point of intersection of this line and the protractor, which is graduated for the co-efficient of ocular rigidity, gave the ocular rigidity for the eye.
The ocular rigidity of both eyes was determined, a couple of days before and 6 to 12 weeks after the cataract operation.
| Results|| |
In 33 cases, the pre-operative average ocular rigidity was 0.0241, which varied from 0.011 to 0.035. While its post-operative average value was 0.0239 varying from 0.013 to 0.041. It decreased in 19 (57.5%), increased in 10 (30.3%) and remained unchanged in 4 (12.2 %) cases.
In the unoperated eyes, which served as the control, the average ocular rigidity prior to the operation was 0.023 while it was 0.225 after the operation in other eye. Pre-operative ocular rigidity varied from 0.016 to 0.037, while post-operatively it ranged from 0.017 to 0.029. Within the group, the post-operative ocular rigidity was increased in 12 cases (36.4%) unchanged in 4 (12.2%) and decreased in the remaining 17 (51.4 %) cases.
| Comments|| |
Dreager reported a decearse in the ocular rigidity after intra-ocular surgery, due to its effect on the ocular coats. Miller et al  on the contrary, concluded that the ocular rigidity was not significantly altered by the cataract surgery. His observations were also I coroborated by Yunossada  the present study, the range of variation in ocular rigidity was very nearly the same in operated and unoperated eyes.
Statistical analysis, by the application of T test shows that the calculated T value in operated eye (0.715) and unoperated fellow eye (0.74) is lesser than the tabulated T value (1.96) at 5% of significance of 32° of freedom. We conclude on the basis of statistical analysis that ocular rigidity is not significantly affected by uncomplicated cataract extraction.
Thus our observations are in complete agreement with those of Miller et al  and Yunossada 
| Summary and Conclusion|| |
Pre- and post-operative study on ocular rigidity in 33 cases of cataract, did not show any significant change after cataract extraction.
| References|| |
DREAGER J.: Docum. Ophtha'. Den Haag, 13, 431 (1959), cited in 2 p. 38.
GLOSTER J.: Tonometry and tonography (1st edition). J and A Churchill Ltd. London (1966).
MILLER J. E., KESKY G. R. and BECKER B.: Cataract extraction and aqueous outflow. A.M.A. Arch. Ophthal. Chicago. 58, 401-406 (1957).
YUNOSSADA M. K.: Klin. Mon. Augenheilk, 141, 846-852 (1962), taken from Amer. J. Ophathal. 55, 1293 (1963).
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