|Year : 1983 | Volume
| Issue : 5 | Page : 525-527
A clinical evaluation of oxygen and carbon dioxide values and pH in the human aqueous humour in normal and cataractous eyes
RG Sharma, YC Mishra, GL Verma, Kishan Lal
Department of Ophthalmology, S.M.S. Medical College & Hospital, Jaipur, India
R G Sharma
Deptt.of Ophthal., S.M.S. Medical College & Hospital, Jaipur
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sharma R G, Mishra Y C, Verma G L, Lal K. A clinical evaluation of oxygen and carbon dioxide values and pH in the human aqueous humour in normal and cataractous eyes. Indian J Ophthalmol 1983;31:525-7
|How to cite this URL:|
Sharma R G, Mishra Y C, Verma G L, Lal K. A clinical evaluation of oxygen and carbon dioxide values and pH in the human aqueous humour in normal and cataractous eyes. Indian J Ophthalmol [serial online] 1983 [cited 2020 Jan 21];31:525-7. Available from: http://www.ijo.in/text.asp?1983/31/5/525/29536
The avascular lens almost entirely depends upon aqueous humour for its nourishment. Lenticular metabolism is mostly anaerobic and to some extent aerobic-an auto oxidative metabolic system wherein glutathione, Vit. C. and riboflavin are the essential requirements. A cataractous lens is an asphyxiated lens producing changes in pH, pCO 2 and pO 2 of the aqueous.
Accurate measurement of the pCO 2 and pH values of the aqueous in normal and cataractous eyes can throw a lot of light on the utilization of 0; and acidic waste products. Therefore, it was considered worthwhile to analyze the aqueous humour for their study in normal, cataractous and glaucomatous eyes by a highly sensitive radiometer technique.
| Material and Method|| |
The break up of 45 cases selected from the Upgraded department of Ophthalmology, S.M.S. Medical College Hospital Jaipur for this study is as given below:
During surgery the aqueous was aspirated with tuberculin syringe and a rubber cork was applied immediately to the tip of the needle to prevent the contact of aqueous with atmosphere. The samples were immediately taken to biochemistry lab for estimation of pO:, pCO2 and pH. by the micromethod of Siggard Anderson, Engel, Jorgson and Atrupt . It is highly sensitive radiometer technique which can analyse micro quantities of fluid and was not available to previous workers.
(Control group pH)
| Observations|| |
The study of the control group in the present series revealed that pH values varied from 7.50 to 7.60 with a mean of 7.56. Gold Schmiedt  and Baurmann  reported pH value of 7.37 and 7.32 respectively which is slightly low as compared to the present studies.
The mean pCO, values in the present series was 40.40 mg. Hg. while Baurmann  found it to be 40.50 mg. of Hg. and Kronfeld  recorded the pCO 2 value to be 38.50 mg. Hg. which are almost similar to the observations in the present work.
The pO 2 in the present series ranged from 50 mg. to 55 mg. with an average of 52.9 mg. of Hg.
In cataractous cases in present series, the pO 2 was found to be 64.20 mg. of Hg., in immature cataracts, 65.40 mg. of Hg., in mature cataract and 68.40 mg. of Hg. in hypermature cataracts. This clearly shows that the pO 2 goes on increasing as the cataractous changes advance.
Theil  recorded the pO 2 values of the aqueous humour in cataractous cases varying from 53.68 mg. of Hg. with a mean 59.68 mg, of Hg. while Kleifeld and Neumann  found the lower value 52.6 mm of Hg.
The mean pH value in the present series in immature cataract was observed to 7.37 which become more acidic in hypermature with a pH of 7.30 while the mean pH value of the control group was 7.5 in the present series. Baurmann  observed the mean pH value of 7.37 in all types of cataractous cases which is at par with our observations of its becoming slightly acidic.
The pCO 2 in the present study had an average of 36.2 mm of Hg. in immature cataract and 36.01 mm Hg. in mature cataract and 38.22 in hypermature cataract. This shows a significant change as compared to the control group (40.40 mg. Hg.) and proves that lens metabolism tremendously decreases due to cataractous changes and consequent lesser production of CO 2 in cataractous lens. Thiel  observed the pCO 2 level to vary from 35 to 44.5 mm of Hg. which is quite close to our observations.
| Conclusion|| |
It is apparent from the above study that the 0 2 consumption of lens declines with cataractous changes and increased I.O.P. leading to increased pO 2 value in the aqueous, there is less production of CO 2 hence pCO 2 value of the aqueous is reduced. pH of the aqueous is also reduced because of greater anaerobic metabolism leading to accumulation of acid metabolites in the aqueous.
| References|| |
Siggard-Anderson, et. al., Scand. J. Clin. Lab. Invest., 12, 172, 1960.
Goldschmidt, M., Heidelberger Berichte S. Zus. Heidelberger., 191-197, 1925.
Baurmann, M., Albrecht V., Graefes. Arch. Ophthal., 118, 360, 1927.
Kronfeld, P., Albrecht V., Graefes. Arch. Ophthal., 118, 606, 1927.
Thiel, H.J., Albrecht V., Graefes, Arch. Klin. Exp. Ophthal., 174, 127, 1967.
Kleifeld, O., and Neumann, H.G., Klin. Mbl. Augenheilk., 135, 224, 1959.
[Table - 1], [Table - 2], [Table - 3]