|Year : 1990 | Volume
| Issue : 2 | Page : 78-80
A comparative study of ophthalmodynamometry in hypertensive and non-hypertensive cases
SS Grewal, RK Grewal, SS Shergill
Dept. of Ophthalmology, Dayanand M College, Ludhiana, Punjab, India
S S Grewal
654- Gurudev Nagar,Ludhiana-141001. (Punjab)
Source of Support: None, Conflict of Interest: None
Ophthalmodynamometry was done on 100 hypertensive cases and 100 non-hypertensive cases who had clear media and no glaucoma. The ratio of the pressure mean ophthalmic: pressure mean brachial in the non-hypertensive group was 0.71:1.0, which rose to 0.78:1.0 in the hypertensive group. The ophthalmic humeral diastolic ratio increased with the severity of fundus changes. The pressure mean ophthalmic showed higher values with increasing grades of fundus changes. Those cases having a pressure mean opthalmic higher than the expected value in the hypertensive group as compared to the cases having a pressure mean ophthalmic lower than the expected value, were at a greater risk or had a graver prognosis. The importance of ophthalmodynamometry is stressed for the prognosis of hypertension along with the fundus examination.
|How to cite this article:|
Grewal S S, Grewal R K, Shergill S S. A comparative study of ophthalmodynamometry in hypertensive and non-hypertensive cases. Indian J Ophthalmol 1990;38:78-80
|How to cite this URL:|
Grewal S S, Grewal R K, Shergill S S. A comparative study of ophthalmodynamometry in hypertensive and non-hypertensive cases. Indian J Ophthalmol [serial online] 1990 [cited 2020 Feb 27];38:78-80. Available from: http://www.ijo.in/text.asp?1990/38/2/78/24532
| Introduction|| |
Ophthalmodynamometry is a procedure of measuring the arterial blood pressure in the ophthalmic artery when external pressure is applied to the globe. The diastolic pressure is measured when complete collapse of the central retinal artery occurs after pressure by the ophthalmodynamometer and systolic pressure when the first pulsation re-appears when the pressure of the dynamometer is lessened after complete interruption of the blood flow.
Paul Bailliart  laid the foundations of ophthalmodynamometry. He found the average value of retinal diastolic pressure as 47 mm of Hg and retinal systolic pressure as 78 mm of Hg. He also concluded that these pressures varied with the general blood pressure giving the relation of the ophthalmic to the humeral pressure in diastolic as 45: 100 and systolic as 54: 100.
| Material and methods|| |
Ophthalmodynamometry was performed on a total of 200 cases. These were divided into two groups of 100 cases each of non-hypertensive and hypertensive cases respectively. All cases had clear media and were not having glaucoma. Patients having brachial systolic blood pressure less than 150 mm of Hg and brachial diastolic blood pressure less than 90 mm of Hg were considered non-hypertensives. In the hypertension group, all cases were known hypertensives and were on anti-hypertensive treatment. Hence in a few of these cases the brachial systolic blood pressure was less than 150 mm of Hg and 90 mm of Hg respectively. Since they were on anti-hypertensive treatment they were considered definitely hypertensives. The ophthalmodynamometer used for the study were those of H.K.Muller No. 576 and No. 716 (Hypertensive model) made by Ogi, Berlin. The following procedure was adopted:
1. The pupils were dilated with 10% Phenylephrine and fundus examination done for any arteriosclerotic/hypertensive changes.
2. Xylocaine 400 was instilled in each eye and I.O.P recorded with a Schiotz tonometer.
3. The brachial blood pressure was recorded from the right and left upper arm at heart level, with the patient in a sitting position and the cuffs were left in place on each arm during the procedure.
4. Under dimmed illumination the ophthalmoscope was focussed at the patients right disc. Then the assistant standing behind the patient, applied pressure with the ophthalmodynamometer from the temporal side avoiding the external canthus and aiming horizontally towards the centre of the eye-ball. The patient maintained straight ahead fixation with the other eye. The first complete collapsing pulsation of the C.R.A. or one main branch on the disc was instantaneously reported to the assistant who read off the corresponding scale units on the ophthalmodynamometer. Pressure was slightly released and even more slowly increased until the first pulsation appeared once more. The lower of the two readings was jotted down. The same procedure was done on the left eye.
| Observations|| |
Out of the 100 hypertensive cases 56 cases were males and 44 females. 54% cases had normal fundi. 4% had grade I, 2700 grade. 11, 14% grade III and 1 °0 grade IV retinopathy respectively. Males showed a greater incidence of fundus changes as compared to females. In grade I retinopathy 25% were males, in grade II 66.6°0 males, in grade 11164.3% and in grade IV 100% males.
In the hypertensive group the average diastolic brachial pressure was 95.8 mm of Hg. varying from 71.6 to 119.6 mm of Hg. The average systolic brachial pressure was156 mm of Hg, varying from 102 to 204 mm of Hg. The pressure mean brachial in hypertensive cases was on an average 120 mm of Hg, varying from 84 to 153 mm of Hg. The ophthalmic artery diastolic pressure was on an average 67.2 mm of Hg varying from 45.3 to 107.7 mm of hg. The ophthalmic artery systolic pressure was on an average 119.9 mm of Hg varying form 64.6 to 175.5 mm of Hg. the pressure mean ophthalmic was on an average 94.6 mm of Hg varying from 68 to 135 mm of Hg.
In the non-hypertensive group: The average diastolic brachial pressure was 79.8 mm of Hg (69 to 90 mm of Hg), average systolic brachial pressure was 127.0 mm of Hg (109- 149 mm of Hg). The average diastolic pressure in the ophthalmic artery was 49.3 mm of Hg (34.8 to 80.3 mm of Hg) and average systolic pressure in ophthalmic artery 96.4 mm of Hg (57-94 mm of Hg). In the hypertensive group: The average ratio of ophthalmic artery diastolic pressure: humeral diastolic pressure was 0.7 : 1.0. The average ratio of ophthalmic artery systolic pressure : humeral systolic pressure was 0.77 :1.0.
In the non-hypertensive group: The ophthalmic artery diastolic pressure: humeral diastolic pressure was 0.61 : 1.0. The ophthalmic artery systolic pressure: humeral systolic pressure was 0.75 : 1.0.
Thus the diastolic ratio rose from 0.6:1.0 in the non-hypertensive group to 0.71 : 1.0 in the hypertensive group.
The pressure mean ophthalmic : pressure mean brachial rose from 0.71 : 1.0 in the non-hypertensive to 0.78:1.0 in the hypertensive group.
It was also found that with the increasing grade of retinopathy the ophthalmic : humeral diastolic ratio also rose as seen in [Table - 1].
There was no significant rise in ophthalmic humeral systolic ratio.
The relation of the pressure mean ophthalmic to that of fundus changes in the hypertensive group was evaluated as shown in [Table - 2].
A graph was plotted between the pressure mean ophthalmic and pressure mean brachial in hypertensive and non - hypertensive cases. It was evident that in the hypertensive group, the majority of the cases had a pressure mean ophthalmic higher than the pressure mean ophthalmic expected for a given pressure mean brachial as seen in graph II. In the non - hypertensive cases, most of the cases had a pressure mean ophthalmic lower than the pressure mean ophthalmic expected for a given pressure mean brachial as seen in graph I. In a two months follow up of all hypertensive cases a comparison was made between those cases having a pressure mean ophthalmic more than the expected pressure mean ophthalmic and those cases in which pressure mean ophthalmic was lower than the expected pressure mean ophthalmic. It was found that in those cases with a pressure mean ophthalmic higher than the expected value of pressure mean ophthalmic, one case expired and two cases landed into hypertensive encephalopathy. These three cases had grade II retinopathy changes. In those cases having a pressure mean ophthalmic lower than the expected pressure mean ophthalmic, none progressed to hypertensive encephalopathy..
| Discussion|| |
In systemic hypertension a high blood pressure is also recorded in the ophthalmic artery. The eye shows involvement in the form of retinopathy. A higher diastolic blood pressure as compared to systolic blood pressure is of greater significance. Also there seemed to be no direct relationship between the magnitude of hypertension and retinal changes. Lal et al  found 14.5% of eyes in the hypertensive group were without any fundus changes. Earlier also it was found that hypertension was more severe in its course and complications in men . In our series also, males showed a more severe course.
In our series in the hypertensive group the retino brachial diastolic ratio was determined as 0.70 : 1.0 while the retino brachial systolic ratio was 0.77: 1.0. It is evident that the retino brachial diastolic ratio rose from 0.61 : 1 .0 in the non-hypertensive group to 0.70: 1.0 in the hypertensive group. The retino brachial systolic ratio rose only from 0.75: 1.0 in non-hypertensives to 0.77: 1.0 in the group.
Aggarwal  found that normally the retinal diastolic pressure bore a ratio of 0.45 : 1.0 with the brachial diastolic pressure. In case of malignant hypertension the ratio rose as high as 0.80 : 1.0. In our study, similar results pointed out a diastolic retino brachial rise in hypertensives. In all probabilities the retinal changes were not related to retinal artery pressures but a disproportionately high diastolic pressure was of a graver importance. Aggarwal et al  also concluded that a rise in pressure mean ophthalmic ; pressure mean brachial ratio was probably a better indicator than the ophthalmo humeral diastolic ratio although both showed a rise in the present series. The pressure mean ophthalmic : pressure mean brachial rose from 0.70: 1.0 in the non-hypertensive to 0.78: 1.0 in the hypertensives.
It was also found in our series that with the increasing grade of retinopathy the ophthalmic humeral diastolic ratio also rose. Identical views were expressed by Aggarwal et al . It may also be said that there was a parallel between the degree of retinal involvement and gravity of clinical picture of the disease, on which is based the prognosis relative to life expectancy. In grade I retinopathy changes, life expectancy in such cases is equal to that of the non-hypertensives. In severe malignant hypertension (retinopathy grade IV) life expectancy is quite poor. In our series the pressure mean ophthalmic showed a rise in relation to the fundus changes. The pressure mean ophthalmic did not show significant rise with the duration of hypertension.
In the non-hypertensive the pressure mean ophthalmic showed a value less than the expected pressure mean ophthalmic for a given pressure mean brachial as seen in graph I. In the hypertensive group, majority of the cases had a pressure mean ophthalmic higher than the expected pressure mean ophthalmic for a given pressure mean brachial as was evident from the graph II. in a two month follow up of hypertensive cases it was found that in those cases having a higher pressure mean ophthalmic than the expected pressure mean ophthalmic, one case expired and two case landed in hypertensive encephalopathy. In those cases who had a pressure mean ophthalmic lower than the expected pressure mean ophthalmic, none of them progressed to hypertensive encephalopathy. Thus it seemed that those cases having a pressure mean ophthalmic higher than the pressure mean ophthalmic expected were at a greater risk of suffering from complications or the prognosis was graver in those patients.
We also concluded that a disproportionate rise in the retinal diastolic pressure seemed to be more uniform, reliable and consistent.
Thus the possibilities of evaluation of each case of hypertension could be improved by the addition of dynamometry to the other examinations. This procedure has not become popular in this country and not easily understood by the fellow ophthalmologists, but it is a very simple, non-invasive procedure for the prognosis of hypertension.
| References|| |
Bailliart, P.(1917): Quoted by Duke Elder, 1962. System of Oph. thalmology, 7: 363. Henery Kempton, London.
Lal, S.K. Jain, I.S..Gupta, S.D, Wahi. P.L. (1974): Indian Journal Ophthalmology 22(2) :1-05), 1974.
Harrison's principles of Internal Medicine. 8th Ed., Chap. 250, pp. 1307, 1313, 1317.
Aggarwal, L.P. (1962) : Text Book of Eye Diseases, Ist Ed., 256. Kitab Mahal, Allahabad.
Aggarwal, L.P.. Patnaik, B., Batta, R.K., Gupta, A.K. (1965): Oriental arch.Ophthal., 3 : 238.
[Figure - 1], [Figure - 2]
[Table - 1], [Table - 2]