|Year : 1984 | Volume
| Issue : 2 | Page : 85-87
Amplitude of accommodation in different age groups and age of on set of presbyopia in Bengalee population
DN Chattopadhyay, GN Seal
Eye Infirmary, Calcutta Medical College, Calcutta, India
D N Chattopadhyay
Eye Infirmary, Calcutta Medical College, Calcutta
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Chattopadhyay D N, Seal G N. Amplitude of accommodation in different age groups and age of on set of presbyopia in Bengalee population. Indian J Ophthalmol 1984;32:85-7
|How to cite this URL:|
Chattopadhyay D N, Seal G N. Amplitude of accommodation in different age groups and age of on set of presbyopia in Bengalee population. Indian J Ophthalmol [serial online] 1984 [cited 2020 Jan 27];32:85-7. Available from: http://www.ijo.in/text.asp?1984/32/2/85/27377
The amplitude of accommodation in normal human eyes have been studied by various workers at different times in different parts of the world and it was observed that it varied widely among normal individuals. Similarly age of onset of presbyopia also varies widely among normal individuals. Donders and Duane worked on the amplitude of accommodation in European subjects. From their observations it was found that a person develops presbyopia at about the age of 45 years. Rambo and Rambo and Sangal published some reports on amplitude of accommodation in Indians. According to them, Donders' and Duane's statistics and graph of accommodation are not, applicable for Indians and probably not even for large section of human race. In clinical practice also we very often find that the Indians need presbyopic glass much before the age of 45 years.
| Materials and method|| |
The present study was conducted on patients attending the out patients department.800 eyes of'400 cases were subjected to external examination and fundoscopy. Refractive conditions of the eyes were thoroughly checked. Normal eyes free from any external or internal diseases and with visual acuity of 6/6 or 6/6(P) (with ametropic correction if any) were selected for the present study.
The near point of accommodation of each eye was recorded separately by R.A.F. nearpoint rule. Ametropic cases were given full correction before recording the near point of accommodation. In this study Duane's method (clear to blur method) was adopted.
| Observations|| |
Mean amplitude of accommodation in 610 year age-group is 14.5D and it diminishes more or less regularly so that in the 61-65 year age group, it comes down to,0.8D [Table - 1] and [Figure - 1].
From [Table - 1] it is obvious that the mean age of onset of presbyopia is some where between the age of 31 to 40.
In the present study, we considered a person to be presbyopia when his amplitude of accommodation is reduced 4,0 Die. when his punctum proximum is-25 cms. away from the eye.
From [Table - 2] we can estimate the particular age (X) in this series, at which the amplitude of accommodation (Y) is 4.00 D. The equation to regression line of X on Y is
X on Y
('r' is the coefficient of correction; V y and V x are the standard deviations, x and y are the deviation of the value of X and Y from their respective means Mx=35.50,
| Discussion|| |
Amplitude of accommodation is not a fixed quantity. It varies primarily with age. various workers have studied amplitude of accommodation in various populations. All of them observed that amplitude of accommodation diminishes steadily with the advancement of age. Donders (1864) found that amplitude of accommodation diminishes from 14.C D at the age of 10 years to 0 at the age of 7C years.
In the present study also it is observed that accommodation diminishes gradually as the age increases. On detail analysis in relation to age-groups, it is noted that in the age-group of 6-10 years the amplitude of accommodation is 14.5 D, in the age-group of 11.15 years it is 10.6 D and so on [Table - 1]. In the last age group of the series (61-65 years) it is only 0.81).
In the study conducted by Duane, it was shown that in ages of 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 years the amplitude of accommodation was 13.4D, 12.3 D, 12.3 D, 11.1 D, 9.9 D, 9.7 D, 5.8 D, 3.6D,1.9 D, 13 D,1.2 D, respectively, In the age group of 64 to 72 years, the mean amplitude was between 1.1D to 1.0 D. It was also observed that age of onset of presbyopia is about 45 years.
Hirose charted the standard values of accommodation in normal Japanese population. For 5,10,15, 20, 25, 30, 35, 40, 45, 50, 55. 60, 65, and 70 years, amplitude of accommodation was 1413, 12D, 9D, 8D, 7D, 6D, 513, 4D, 2D, 1D, 0.5D, 0.25D, 013, respectively.
In our present series, we have noticed that amplitude of accommodation is practically the same as for European and Japanese in the earlier groups, but falls rapidly in the age groups from 16-20 years to 41-50 years. This is in conformity with the observations of Rapheal, who found that the lowering of accommodation occurred particularly in the age groups from mid thirties to mid fifties among the population of Israel.
Rambo reported that amplitude of accommodation among the Indians fall more rapidly than the Europeans after the age of 15 years and in the Indian population presbyopia develops at the age of 37th years. This calls for earlier correction for presbyopia in the average Indian subject. Dhir studied accommodation in 500 Indian eyes and on comparing his results with Duane's figures, found no difference as had been observed by Rambo.
| Summary|| |
In the present study, 800 eyes of 400 Bengalee subjects of different age groups ranging from 6 to 65 years with normal visual acuity (corrected or uncorrected), were considered for determination of amplitude of accommodation. It was found that the amplitude of accommodation among the bengalee population is practically the same as that of European and Japanese in the earlier age groups but falls rapidly from the age groups of 16-20 years to 41-50 years. The average age of on set of presbyopia among the Bengalee population is 35 years. This calls for earlier correction of presbyopia in the average Bengalee subject.
| References|| |
Donders F.C., 1864: Anomalies of accommodation and refraction of the eye bond., 1864
Duane A., 1922: Amer. Ophtlialmol 5: 865
Rambo V.C., 1957: J. All India Ophthal. Soc., 5: 51
Rambo V.C. and Sangal, 1960: Amer. Ophthalmol:993
Hirose I, 1968: Rinso Ganka, 22: 523
Rapheal J., 1961: Brit. J. Physiol. Optics., 18: 181
Dhir B.K., 1960: Proc. All-India Ophthal. Soc., 19:100.
[Figure - 1]
[Table - 1], [Table - 2]