The influence of changes in the intraocular circulation on the intraocular pressure / by E.E. Henderson, F.R.C.S., and E.H. Starling, F.R.S. (from the physiological laboratory, University College).

  • Henderson, E. E.
Date:
[1904?]
Catalogue details

Licence: In copyright

Credit: The influence of changes in the intraocular circulation on the intraocular pressure / by E.E. Henderson, F.R.C.S., and E.H. Starling, F.R.S. (from the physiological laboratory, University College). Source: Wellcome Collection.

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    [Reprinted from the Journal of Physiology. Vol. XXXI. No. 5, 1904.] THE INFLUENCE OF CHANGES IN THE INTRA¬ OCULAR CIRCULATION ON THE INTRAOCULAR PRESSURE1. By E. E. HENDERSON, F.R.C.S., and E. H. STARLING, F.R.S. (Nine Figures in Text.) {From the Physiological Laboratory, University College.) In a recent investigation by one of us (E. H. S.), of the factors deter¬ mining the amount and composition of the intraocular fluid which is constantly being poured out into the eyeball, it was found impossible to arrive at definite conclusions on account of the striking discrepancies which exist between the results of various observers as to the dependence of intraocular pressure on blood-pressure; and we have therefore subjected the question to a fresh examination. The problem of measuring intraocular pressure is analogous to that of measuring the intracranial pressure. We have a cavity with walls which, under the conditions of the experiment, can be regarded as approximately rigid. In this cavity fluid is being constantly poured out from the ciliary process, and absorbed through the canal of Schlemm at the anterior angle of the eye. Under normal conditions the intraocular tension determines an exact balance between the amount of fluid secreted and the amount absorbed. If we wish to determine this pressure it is evidently necessary that in the determination no fluid shall either enter or leave the eyeball. For this purpose, therefore, it is not sufficient to attach a manometer to the interior of the eyeball. We must use a method similar to that employed by Bay 1 iss and Hill(1) in the determi¬ nation of intracranial pressure, namely, a method in which there is no movement of fluid, but a bubble of air, serving as an indicator, is kept at a given position in the manometric apparatus by opposing a counter¬ pressure equal to that which obtains in the interior of the eyeball. The arrangements we made use of are represented in the accom¬ panying diagram (Fig. 1), and consist of a gilt-steel needle which is 1 Towards the expenses of this research a grant was made by the British Medical Association on the recommendation of the Scientific Grants Committee of the Association. PH. XXXI. 21