The diagnosis of a case of couched cataract presents the surgeon with three distinct problems: (1) To ascertain whether a couching has been done or not; (2) to discover the new position of the lens and its condition; and (3) to decide whether it is advisable to operate. Only those who work in lands, where the couching of cataracts is an everyday occurrence, will take a deep concern in such questions; but the subject has a scientific interest which cannot fail to appeal to any one who devotes his serious attention to the large questions of ophthalmology.

It might be thought that the simple and obvious way to ascertain whether a couching had been done would be to ask the patient or his relatives. In a large number of cases this is of course sufficient; but in India, at all events, there are many who will deny the operation they have undergone. This is due to the fact that it is widely known among the people that the British surgeons view the coucher and all his methods with extreme disfavour. Patients are therefore reluctant to admit having consulted him, and they also are afraid lest treatment should be refused them, once their true history is known; for it is common knowledge amongst them that the Western practitioner is extremely reluctant to interfere with an eye which a coucher has spoilt. It is well, therefore, to consider carefully the grounds on which the physical diagnosis of a couched lens should rest.

We will first consider the case of those eyes in which the cataract has been definitely removed from the neighbourhood of the pupil. These present certain well-marked signs: (1) The pupil is brilliantly black, and (2) the plane of the iris is flat. It may seem strange to insist upon these points, but to the trained eye they are so obvious that a diagnosis can often be made, as soon as the patient takes his seat in the out-patient room, in front of the surgeon. The quality of the blackness of the pupil is difficult to put into words, but it arrests the attention by its contrast to the ordinary appearance of the pupil in people so advanced in life as the subjects of cataract usually are. The phenomenon is due to the whole cataract, capsule and all, being thrust away from the pupillary area, and it can be equally well seen in cases which have undergone the intra-capsular operation. Then, with regard to the flattening of the iris, the trained eye is used to the appearance presented by the slight forward convexity of that membrane as a result of the presence of the lens behind it; whereas the complete removal, not merely of the lens, but also of the support of the suspensory ligament, makes the iris flatten out in its own plane.

On close inspection we notice other signs. (3) The iris, deprived of the support of the lens, is often tremulous. This can best be observed if the patient is bidden to move his eye sharply in different directions. (4) Scars may be seen on the iris. These are the result of tears of the membrane during the operation. In some cases they are associated with an irregularity of the pupil, which may be extreme, or with a limitation or absence of pupillary movements. In other cases the immobility of the pupil, which may be absolute, is associated with (5) an atrophic condition of the inner free margin of the iris. Such a condition is only met with in very long-standing cases. Transillumination of the eye will sometimes show up the scars, or the atrophic condition just referred to, as light spaces against the rest of the dark background of the iris. (6) A careful study of the cornea, or of the sclera in its neighbourhood, will often reveal evidence of the wound made by the instrument during couching. In the cornea these take the form of small nebulæ or leucomata, lying just within the limbus, and usually in the temporal quadrant. In one case a persistent fistula was met with, as the result, presumably, of the bursting of a staphyloma along the original track of a septic wound. Scars in the sclera are much more difficult to distinguish, but they can sometimes be detected by the pigmentation which overlies them; such pigmentation may be due to the inclusion of uveal pigment in the track of the wound, as has been shown by our pathological specimens: but this is not the only possible explanation of the discoloration, for in dark-skinned races a certain amount of pigmentation is not uncommon after injuries of the conjunctiva. In one of the eyes we examined, there was a filtering scar over a fistula which had formed along the track of a scleral wound. (7) We come now to the leading feature in the diagnosis of these cases—viz., the recognition of the displaced cataract in its new position within the eye. In the rare event of a lens being dislocated into the anterior chamber and fixed there, its presence can be easily recognised. Again, in a large number of the cases which present themselves in the out-patient room, the cataract can be seen floating freely in the vitreous, and bobbing up and down with the movements of the eye. In the case of the milky Morgagnian cataracts, or of those cortico-nuclear cataracts which present a glistening and pearly-sectored appearance, it would be difficult even for a beginner to fail to see the lens, which usually lies at the lowest part of the eye. As the patient sits in front of the surgeon, the gleam of the white cataract can be caught each time he looks downward, even though a distance of two or three feet may separate him from the observer. In the case of darker cataracts, such as the pigmented nuclear ones, frequently met with in Indian practice, a closer examination is required.

The patient must be brought nearer to the observer, and facing a good source of illumination. The surgeon then focusses the light on the pupil by the aid of a lens, bidding the patient at the same time to look downward. If this fails, the patient is instructed to bend his head forward, holding the face horizontal; the surgeon then places one closed fist on the back of his head, and gives a number of sharp raps on it with his other fist; when this is done, it is often found that the lens has floated forward on to the pupil. If the patient’s head be now quietly raised, the lens can be seen dropping gently away from the pupil, which turns from white or brown (according to the nature of the cataract) to black as it does so. The experiment can be repeated again and again. Sometimes the lens falls away from the pupil so quickly that the surgeon must stoop down and look up at the eye in order to see it. If even after this test he fails to see the cataract, it is safe to assume that it is tied down in its new position by inflammatory adhesions excited by the septic matter introduced at the time of operation. Such adhesions may consist merely of delicate fibrils of exudate, which slightly increase the consistency of the vitreous body, and so to a small extent limit the excursions of the lens; or they may be represented by firm and highly organised fibrous tissue, which mats the lens in its new position, and which may be so strong that even a post-mortem dissection would fail to disengage the cataract from its adventitious position. This subject has been dealt with much more fully in the chapter on pathology. The dilatation of the pupil by a mydriatic will often make it quite easy to discover the whereabouts of the cataract, especially if a strong light, whether natural or artificial, is focussed on the eye by means of a lens. Natural light is preferable to artificial if possible, especially in a country like India, where powerful daylight can be counted on during a large part of the year. The advantage of the white light is especially marked when dealing with brown or dark-coloured cataracts. An examination with the ophthalmoscope or with a transilluminator may sometimes be of value, but in the class of cases we are now discussing, these are seldom of much use, if the examination just described fails to reveal the whereabouts of the cataract.

There remain a few points of interest which deserve mention. Though in the great majority of couched eyes the cataract lies in the lowest part of the globe, it may be found either to the inner or to the outer side, or even in the upper half of the eye. Sometimes it flaps backward and forward with the movements of the globe, swinging on a hinge, which evidently consists of the remaining fibres of the suspensory ligament, and which may be situate in any possible direction, though most often it lies below. It will be readily understood that if this hinge is situate below, or to the inner or outer sides, the lens will flap away from the pupil downward, or to the hinged side, as the case may be. It is not inconceivable that, in repeatedly doing so, it may inflict some measure of injury on the neighbouring part of the ciliary body and retina, and may thus excite a local inflammation which will tend in time to tie the cataract permanently in the new position towards which it flaps, away from the pupil. In the event of the hinge being in one of the three directions now under discussion, the cataract will tend to fall forward on to the pupil only when the patient stoops forward, so as to bring his face into the horizontal plane. When the hinge is situate above, the latter is one of the few positions of the face in which the pupil clears itself in ordinary cases; but one meets with instances in which, despite the hinge being above, the pupil remains clear except when the face is horizontal, the lens lying most of the time in the upper segment of the eye. There is another factor, and probably a more frequent one, than that of the local injury inflicted by the lens during its movement, which tends to tether it in situ. This is the increasing consistence of the vitreous, due to the deposit within it of inflammatory matter, a point which has already been alluded to.

Our next consideration is that of the cases in which the cataract still lies behind the pupil. It then seldom, if ever, is in absolutely normal position, and it very frequently is found to have been moved bodily downwards or to one side, or obliquely. Again, but more rarely, it may be tilted backward at an angle with the plane of its normal position. In a great number of cases the history will help one, and, even when the patient denies couching, he will very often admit to having had “medicine applied to his eye by a native practitioner.” Should no such evidence be forthcoming, there may still remain that of the lesions to the cornea, the sclera, or the iris, to which attention has already been directed in the previous section.

From these cases we pass on to consider those in which the lens cannot be seen at all, owing to the occlusion of the pupil. Here our difficulties are greater still, and, if the history fails us, we must fall back on a careful search for signs of wound scars in the cornea or sclera, or of tears in the iris. A point which is always suggestive is the existence of a cataract in the opposite eye. In such cases as these, the contents of the chamber may be found to consist of pus or of blood.

Our next group is a still more difficult one, for in it no fundus reflex can be obtained. It embraces a number of conditions which may be shortly dealt with in turn: (1) Those in which the vitreous body has been converted into a more or less highly organised inflammatory exudate, which is impenetrable to the light of the ophthalmoscope. (2) Those in which this vitreous exudate has contracted inflammatory adhesions to the retina, and by its shrinkage has determined the total detachment of that membrane. (3) Those in which the vitreous chamber has become filled with blood. It is obvious that in all such cases our main dependence must be upon the history, though the other indications already outlined may help us in some of them.

Lastly there are the cases in which the eye is undergoing shrinkage, and those in which phthisis bulbi is following panophthalmitis. The history of the signs and symptoms of severe iridocyclitis or of suppuration will, in India at least, always excite a suspicion of couching having been performed, unless the patient has a definite story to tell of some other form of injury. Strangely enough, the inventive faculty of the Indian patient does not rise to the height of vamping a narrative of the kind. If he has had an injury, he tells of it readily. If he has been couched, he stolidly denies that anything occurred to cause his trouble, which he states “simply came of itself.”

It will be observed that in the preceding remarks we have dealt with two of the problems which confront us in diagnosis, for the simple reason that it is very difficult to separate them; to do so would mean needless repetition. The discovery of the new position of the lens, and of the degree of fixation, if any, it has undergone, can hardly be divorced from the question of whether a couching has or has not been performed. Our third problem was to decide whether it is advisable to operate in any cases, and if so, in which. The Baron de Wenzel, in his treatise on cataract,4 records two cases in which his father successfully extracted couched lenses. A number of Anglo-Indian surgeons have had similar experiences, but most of them are reluctant to interfere with these cases oftener than they can help, because, should the operation fail, it is extremely likely that they will unjustly incur the odium for the loss of the patient’s vision. On this subject Maynard wrote (Ophthalmic Review, April, 1903): “It may be justifiable to attempt the removal of a recently couched lens. If not recent, and more especially if the lens is fixed, it is wiser to leave it alone, even if the sight is failing.” To the writer’s mind, the one crying indication for removal of a couched lens is that it flaps across and obstructs the pupil. He agrees strongly with Maynard, that if the lens is fixed it is better left alone; but he is doubtful whether the time element is of very great importance, in comparison with the mobility of the cataract; for a study of the fifty-four globes already dealt with has shown him that the fixation or otherwise of the lens is a question of the amount of septic action set up by the operation. If this is small, the lens may continue mobile, even for a very long period; if it is more severe, the latter will soon be tethered. Dealing with this subject five years ago (Proc. of S. Indian Branch of B.M.A., March 13, 1912), the author wrote as follows:

“We are extremely reluctant in Madras to undertake further operative procedures on an eye in which couching has been performed. Removal of a lens dislocated into the posterior chamber obviously means a wide opening up of the vitreous; and even if the immediate result appears good, there is little guarantee that the benefit will continue. Of eighteen cases in which the lens was removed, twelve obtained better vision at the time, four remained in statu quo, and two were rendered worse. I cannot but think that these statistics would suffer if the cases were followed for some years. On five occasions we undertook the laceration of an after-cataract which blocked the line of sight after couching. In two cases there was considerable benefit, whilst in three vision remained in statu quo ante. In four cases an iridectomy was performed for optical purposes. In two vision improved slightly, whilst in the two others it remained as before.

“Personally I have a strong and growing objection to undertake any operative procedure on a couched eye. Firstly, there is the risk of lighting up a septic explosion, for which the real responsibility lies with the coucher’s original operation; and, secondly, there is the danger of being saddled with the discredit which is justly due to another man’s failure.”

Reviewing these paragraphs in the light of the much better knowledge of the pathology of couching which we possess to-day, he would urge that only freely movable cataracts should be touched, since want of mobility is associated with profound changes in the vitreous due to septic action. The object that a surgeon sets before him, work where he may, is ever the same—“The greatest good of the greatest number.” Failure in such cases as these may play into the hands of the coucher, and enable him to extend his sphere of influence at the expense of the beneficent work of the Western hospitals. The problem in India is a difficult one, in which surgical considerations do not stand alone, but are interwoven with social, moral, and even political questions. Each surgeon must decide for himself what line he will take, and follow it fearlessly.

In this connection, Major Kirkpatrick’s experience5 in Madras is of considerable value, for he has removed a number of couched lenses, and has been “struck by the rarity of vitreous escape, even after fairly extensive investigation with a spoon,” during this operation. He adds: “I have noticed that the vitreous body becomes shrunken and extraordinarily tough, so much so that, when an eye is excised (either for glaucoma or for iridocyclitis following Mahomedan operation), the whole globe can be held up by a strabismus hook transfixing the vitreous, though the latter appears perfectly clear. The vitreous undoubtedly does undergo shrinkage, and leaves a large space, which is occupied by aqueous.” It is plain that he is referring here to cases in which the vitreous body has undergone some measure of inflammatory organisation, which might be expected to limit the mobility of the lens, and it will be of great interest to learn whether the conclusions of so reliable and experienced an observer ultimately coincide with the author’s, that interference should be confined to those cases in which the movements of the cataract within the vitreous body are noted to be free. Once again, let it be emphasised that there are two distinct questions at issue—one the benefit of the individual patient, and the other the good name of Western surgery. Each man must be guided according to the dictates of his own personality and of his environment.