Part 35

_Purulent Ophthalmia_ most frequently occurs in warm climates, and is attended from the first with profuse puriform discharge from the conjunctiva. In the natural state of the organ, the conjunctival discharge is pellucid, and so small in quantity as to be indiscernible; but in this disease it possesses all the external characters of pus, and is secreted in large quantity. The affection commences generally in the under eyelid, with a feeling as if sand or foreign bodies were lodged in the eye. The parts swell very much, and the eyelids become more or less inverted, in consequence of serous effusion into their cellular texture. Frequently the patient experiences an exacerbation of the complaint about three or four hours after each meal. Though the disease usually commences in the conjunctival lining of the eyelids, the external coverings of the ball are often secondarily affected. In some cases the bulb becomes the seat of lancinating pains; its coats give way; the humours are discharged; and the eye sinks, with immediate relief to the patient from the more urgent symptoms, but at the same time with irreparable loss of vision. In other instances the effects are less injurious to the structure of the organ, but equally so to the sense of vision: the cornea becomes dull, and ultimately opaque, or ulcerates, or partially sloughs; the swollen conjunctival surface of the lids is covered with granulations, and secretes a copious puriform discharge, with or without eversion, according to the degree of swelling. At first the lids are more or less inverted, on account of œdematous swelling of the cellular tissue: in the latter stages they are everted by thickening and turgescence of the conjunctiva. This membrane is at first villous and of a dull red colour, relaxed, and its vessels enlarged and loaded; afterwards it becomes hard, almost warty, and continues to discharge puriform fluid. The latter state of the lining of the lid produces disease of the cornea, opacity of a greenish colour, or an ulcer with intolerance of light, and other symptoms of disorganisation proceeding in that tissue. The disease is supposed to be contagious, and was the scourge of the British army for many years after the campaign in Egypt. In that country it seems to be caused by exposure to cold and damp during the night, and the intense rays of light during the day, more especially when these causes act on eyes which have not been accustomed to such vicissitudes. After its invasion, it is communicable to others by contact of the morbid secretion; and in individuals who have been once affected the disease is very apt to recur when they are crowded together in unhealthy situations.

A disease of equal malignity, and resembling in all respects the Egyptian ophthalmia, occurs from the application of gonorrhœal matter to the conjunctiva, or on sudden suppression of the gonorrhœal discharge,—metastasis of the action sometimes takes place from the urethral membrane to the conjunctiva. The eye is seldom saved from the destructive effects of the violent inflammation which follows the contact of the morbid fluid. Of all forms of purulent ophthalmia, the gonorrhœal is the most rapid in its course and destructive in its effects.

Children are not unfrequently the victims of purulent ophthalmia—the _ophthalmia neonatorum_. Immediately after birth the conjunctival lining of the eyelids seems unusually red and turgid, and a great degree of swelling soon takes place, so as to render separation of the eyelids very difficult. Occasionally eversion of the lids occurs, when the child cries, from sudden and forcible contraction of the strong external fibres of the orbicular muscle. In general, the lids soon relapse into their former situation; but sometimes the eversion remains, if the internally projecting tumour of the conjunctiva is allowed to become still more swelled from strangulation, caused by the outer margin of the reflected lid. The inflammation spreads over the ball; and, in general, the swelling of the conjunctiva, being greatest at the circumference of the eye, bulges out the eyelids, and turns in their margins. Puriform matter is secreted copiously, and is confined, more especially when, from inattention, the margins of the lids are allowed to become glued together. They often adhere so firmly as to require a very considerable force for their separation, and when opened the matter gushes out as if from the cavity of an abscess. From confinement of the matter the inflammation is still more increased, and the cornea involved. Whitish specks form on it, or it ulcerates, and the ulcers make their way into the anterior chamber of the eye; or portions of it slough, causing partial loss of the organ and openings into the chamber, in consequence of which the aqueous humour is discharged, and the cornea sinks and becomes flaccid. In many instances the cornea becomes opaque, changed in texture, and increased in thickness, so as to form a convex projection from betwixt the eyelids, termed _Staphyloma_; the sclerotic coat also is occasionally affected in a similar manner. A frequent cause of purulent ophthalmia in children is imprudent exposure of the eyes to strong light, the parent or nurse not remembering that the organ must be gradually accustomed to the stimulus. Exposure to cold may also induce the inflammatory action. The application of leucorrhœal or gonorrhœal matter to the eyes of the child, whilst passing through the vagina of the mother, is perhaps the most common cause of the disease. A very unhealthy state of the constitution accompanies the affection: the scalp and other parts of the surface are frequently covered with eruptions. A singular result sometimes follows the purulent ophthalmia of infants. A small opaque spot is observed on the capsule of the lens, which remains through life a central spurious capsular cataract.

_Inflammation of the Cornea_ supervenes on simple conjunctival inflammation, and frequently on the purulent. The vessels of the part, both veins and arteries, previously carrying single and therefore invisible blood corpuscules, become much dilated, are filled with numerous globules, and hence are rendered red and conspicuous to the unassisted eye. Writers on ophthalmic surgery, in their rage for refinement, speak of three kinds of this inflammation—inflammation of the external or conjunctival covering, of the middle tunics or cornea propria, and, lastly, of the third coat, the capsule of the aqueous humour: such distinctions, however, are found to effect no good practical end, and it is unnecessary to follow them. One particular layer of the cornea may be first attacked, but the whole structure soon becomes involved. The inflammation generally commences in the conjunctival covering. Vision is necessarily much obscured from even slight inflammatory affection of the cornea. Part only of the organ may be affected, but frequently the whole is involved. Sometimes only one or two vessels remain dilated; but still they, passing over the centre of the cornea, render vision indistinct. Opacity of the cornea, to a greater or less degree, always attends dilatation of its vessels.

In inflammation of the internal and middle tunics of the cornea, most of the enlarged vessels which traverse it are seen to be continuations of those that ramify in the conjunctival covering; while the anastomotic vessels derived from the sclerotic coat are smaller and less apparent than those of the conjunctiva. The cornea, and the sclerotic immediately surrounding it, frequently appear to be almost entirely covered with meshes of their dilated capillaries. At first the whole cornea has a clouded appearance, but as the disease advances portions become distinctly opaque, and at these points either lymph or pus is effused. Sometimes matter collects between the laminæ, distends them, and, causing ulceration, discharges itself either into the anterior chamber or externally. Inflammation of the cornea arises frequently from lodgement of a foreign body in it: and ulcers of it are often produced by a similar cause. If the extraneous matter is not removed soon after its insertion, nature commences her endeavours to detach it, and the process employed is ulceration. Sometimes, however, a sac is formed around the foreign body as in other parts, and no ulcer is produced.

Ulceration of the cornea also takes place in order to afford an exit to matter formed between its layers deeply or superficially. Deep abscess of the cornea is by no means a rare consequence of violent inflammatory action in the part. A minute opaque spot is at first seen; this extends, assumes a yellow colour, and does not change its situation on the head being moved. The internal lamellæ may ulcerate in consequence of the pressure; but this seldom happens; the matter is discharged externally. Suppuration in this situation is often attended with much pain. Abscess of the surface of the cornea is of more frequent occurrence than one more deeply seated: from its external covering yielding readily to the pressure of the accumulating matter, it generally assumes a pustular form. The fluid in such cases is sometimes absorbed, and no vestige of disease remains in the part; but more frequently the apex of the pustule gives way, and an ulcer is the consequence. A similar result takes place if an artificial opening is made for evacuation of the matter; and it may be considered as a good rule in practice not to interfere with collections in the cornea, as there is a probable chance of the matter being absorbed, and the cornea regaining its transparency; while it is certain that breach of its surface, in such cases, though made by the most delicate instrument, will give rise to ulceration.

_Pustular Opthalmia_ is at some seasons frequently met with: small pustules, sometimes numerous, form on the conjunctiva, whilst that membrane is turgid and its vessels dilated; the sclerotic conjunctiva around the cornea is their most common situation, but sometimes almost the whole conjunctival surface appears studded with them. When the cornea is affected, the pustules frequently give way, and produce ulceration; and when the pustules are numerous, and surrounded by much vascularity, the part becomes opaque as well as ulcerated.

In weak constitutions _Ulcers of the Cornea_ occur from slight causes,—exposure to strong light, intemperance, inverted or irregular ciliæ, a granulated state of the lining of the lids, or from momentary irritation of the part by extraneous matter. The ulcer appears at first circular, but during its progress it often becomes of an irregular form; its surface is depressed and ragged, and can readily be seen by directing the patient to fix the eye, and then looking at the part from one side. The edges are elevated; and the surface, which is of an ash colour, discharges an acrid colourless fluid, as in similar affections of all surfaces that are covered with a delicate, tense, and exquisitely sensible expansion. Sometimes the ulcer is very minute and superficial, and enlarges very slowly, if at all; but in other instances it extends rapidly in depth and size, with great pain and irritability of the organ, and intolerance of light. Occasionally their increase is expedited by partial sloughing. At first, when the ulcer is minute, the part often retains its natural transparency. But as the disease advances, when the sore spreads superficially either by the sloughing or the ulcerative process, or by both, the cornea becomes opaque, often to a considerable extent, around the ulcerated part; and if the ulcer extends deeply, so as to perforate the tunics, the aqueous humour escapes, the iris falls forward, and the pupil becomes distorted: in either case vision is impaired or destroyed. In some cases great relief follows discharge of the humour, and the consequent flaccidity of the cornea, the ulcers seeming to have been prolonged and irritated by the fulness of the chamber. Sometimes an ulcer will penetrate the laminæ of the cornea, even to the aqueous membrane. This latter tissue may resist the ulcerative process, and will then be pushed forward into the opening by the pressure of the aqueous fluid. This is _the hernia of the aqueous membrane_, so called, instances of which have been known to acquire a considerable size before the bag has given way.

_Abrasion_ of the conjunctival covering of the cornea is produced by accident, or follows incited action of the vessels. The abraded surface either ulcerates, or contracts and heals kindly, with or without opacity of the part. Breach of surface in the cornea,—whether an ulcer, an abrasion, or a raw surface, caused by the giving way of a pustule, or of a small abscess,—is constantly liable to irritation, on account of not being protected by mucous membrane and mucous discharge: even the contact of the tears irritates, and keeps up inflammatory action in the membranes. When the ulcerative process ceases, lymph is effused, and a grayish halo forms around the sore; the ash colour of the surface of the sore disappears, and is succeeded by florid granulations, extremely minute, which fill up the cavity; cicatrisation follows in due time, with subsidence of all the symptoms and appearances of inflammation. There remains, however, an opaque speck of a pearly hue corresponding to the sore, but occupying rather less space. When the cornea is perforated by ulceration, the sore sometimes shows no disposition to heal, becoming a fistulous aperture through which the aqueous humour is from time to time discharged. By this condition of parts vision is much impaired, the cornea being always more or less flaccid. Touching the fistulous opening with the nitrate of silver, reduced by scraping to a very fine point, will often promote a healthy action in the tissue, and effect adhesion of its sides.

The pearly speck which remains after cicatrisation of a corneal sore is termed _Leucoma_, and is permanent. It is generally of an uniform colour, but occasionally a black speck is perceptible in some part of it. For, when an ulcer lays open the anterior chamber, part or the whole of the aqueous humour is evacuated, and the iris falls forward; a portion of the iris falling into the opening, provided this is not in the centre of the cornea, closes it up, and becomes adherent to that part. If the opening is large, the prolapsus of the iris is considerable; and in some cases this membrane, being pressed on by the humours, is forced through the opening in the form of a small bag. This change of position is termed _Hernia of the Iris_; and the dark sacculated portion of the iris which projects from the surface of the cornea is called _Myocephalon_, from its resemblance to the head of a fly. The myocephalon may remain for a considerable time, or may sphacelate and drop away. The pupil is thus rendered irregular, is perhaps nearly obliterated, or is drawn down behind the opaque part, and thereby rendered totally useless to the patient. The impairment of vision caused by Leucoma depends on the size and situation of the speck. The disease is irremediable, though the thin cloudy opacity, which frequently surrounds the leucoma, may be dissipated. The operation of artificial pupil is sometimes required, in order to afford a degree of vision in this affection of the cornea,—as well as in the speck of a similar appearance occasioned by effusion and organisation of lymph betwixt the deep lamellæ of the cornea, and which is termed _Albugo_.

Albugo occurs during the intensity of inflammatory attacks. It also is surrounded occasionally by thinner opacity, but not depressed and unequal on the surface, as leucoma sometimes is. Large and tortuous vessels are generally seen passing into albugines, but meshes of dilated vessels are seldom present. When the affection is recent, it sometimes disappears under proper treatment, especially in young subjects; but the albugo is by no means so readily removed as the _Nebula_, or thin cloudy opacity which is the frequent consequence of obstinate chronic dilatation of the conjunctival vessels. Nebula is superficial, and consists of mere thickening of the conjunctival covering, from lymph having been effused. It impairs vision, but does not destroy it, for the affected part remains semitransparent.

In strumous constitutions specks of the cornea are often accompanied with ulceration of the edges of the palpebræ, and destruction of the ciliæ—_the ophthalmia tarsi_. The margins of the eyelids are red and slightly tumid, and discharge an acrid fluid; the ciliæ are matted together; pustules form at their roots; the bags which secrete them are laid open and destroyed, and they consequently fall out. The affection is often of long duration, and may be in part prolonged by vitiated secretion from the meibomian glands. During its progress it excites very considerable irritation in the whole eye, and, as has been already stated, opacities of the cornea not unfrequently accompany it. Veins become enlarged, and varicose on the conjunctiva, as also their minute ramifications on the clear part of the ball; small reddish lines appear on the cornea, and around them is “diffused a thin, milky, or albuminous humour,” which destroys its transparency at that part. Such spots may be solitary or numerous, and darken the cornea either partially or entirely. They are always surrounded with a fasciculus of enlarged veins.

In elderly people a dim opaque ring, of a greyish colour, sometimes encircles the margins of the cornea, and is called _Arcus Senilis_; but this can scarcely be looked upon as a disease.

Sometimes the cornea presents a _spotted_ appearance; and this state of the organ is generally attended by obstinate inflammatory action in the part. The affection, however, is rare. I have seen several instances of it: in one, both corneæ were spotted, and sight was almost destroyed, without much irritability of the organ. The disease yielded to external stimulants, and the internal use of the bichloride of mercury. It is met with in a chronic and very intractable form.

The cornea may sometimes be rendered dim by _over-distension_, the aqueous humour being unusually copious.

Occasionally _sloughing_ takes place in the cornea from over-action. It is dangerous to the structure and functions of the organ, according to the extent to which it occurs.

_Ossification_ of the cornea is said to take place; but few cases are on record, and these were in very old people.

The cornea sometimes becomes _conical_ to a great degree in persons considerably advanced in life. The cone has its apex in the centre of the organ, seems thick and crystalline when viewed laterally, and when looked on from the front has a sparkling appearance. In some cases it is opaque in the centre, and occasionally its surface is irregular. Vision of objects at any distance is very indistinct; those placed within an inch or two of the eye are most distinctly seen, especially if looked on through a small aperture. The disease usually affects both eyes, though not always in an equal degree. The patients cannot judge accurately of distance, and see objects multiplied and disfigured.

_Staphyloma_ has been already alluded to as an occasional consequence of purulent ophthalmia in children. The cornea is thickened, prominent, and opaque; and in most cases vision is either much impaired or entirely lost. The prominence varies in different cases, being sometimes very little elevated beyond the natural state of the part, while in other instances it protrudes from between the eyelids. After having attained a certain size it often becomes stationary; but very frequently it continues to enlarge gradually. When the prominence is large, much inconvenience arises from the eyelids not being allowed to close; and the eye, being thereby deprived of its natural covering, is extremely liable to become inflamed from external irritation. When one eye is affected with staphyloma, the other not unfrequently becomes similarly diseased.

Dropsy of the anterior chamber, or _Hydrophthalmia_, occasionally takes place in persons of weak constitutions. The aqueous humour is either secreted in greater abundance than it usually is, or absorption is diminished. The cornea gradually accommodates itself to the increase of the fluid behind, and becomes wider and more prominent, but retains its transparency; in looking at the eye, the anterior chamber is seen evidently enlarged, and occasionally the aqueous humour is of a turbid appearance. There is little or no pain in the eyeball, but the patient complains of an annoying sense of fulness and tension in the part. In consequence of the vitreous humour also accumulating, the whole organ is ultimately enlarged considerably, and its motions are thereby much impeded. At first, vision of near objects is impaired, whilst the patient sees very distinctly those placed at a distance; ultimately sight is entirely lost.

_Exophthalmia_, or protrusion of the eye, attends the preceding disease, and is also a consequence of various other morbid actions in the globe and its neighbourhood, especially from the pressure of tumours in the orbit. The chronic enlargement of the bulb is noticed more fully in the succeeding chapters.