Diseases of the Retina

Belladonna is one of the most frequently indicated homeopathy remedies for both hyperaemia and inflammation of the optic nerve and retina. The retinal vessels will be found enlarged and tortuous….

Anatomy.-The retina is the delicate membrane lying be-tween the choroid and the vitreous and extending from the optic nerve to the ciliary processes, where it terminates in a finely in dented border called the ora serrata. Microscopically the retina is divided into ten layers which are from within outward: I. The internal limiting membrane; 2. The nerve-fibre layer; 3. The layer of ganglion cells; 4. The internal molecular layer; 5. The internal granular layer; 6. The external molecular layer; 7. The external granular layer; 8. The external limiting membrane; 9. The layer of rods and cones; 10. The pigment layer.

The internal limiting membrane is a very thin, imperfect membrane, serving to separate the nerve-fibre layer from the vitreous. The fibres of Muller terminate in this layer.

The nerve-fibre layer consists of the axis cylinders of the optic nerve-fibres, which run in a radiating direction to the ora serrata, where they terminate. At the macula lutea these fibres are bent into arches and are so arranged that a large number of them reach the yellow spot than could if they approached it in a radiating direction.

The layer of ganglion cells forms, excepting in the region of the macula, several layers of multipolar cells, having both a nucleus and a nucleolus. A nerve-fibre enters each of these cells and one or more prolongations, extend outward into the inner molecular layer. These ganglionic cells are arranged more closely to each other near the optic nerve than at the ora serrata. The internal molecular layer consists of the fine fibres from the layer of ganglion cells, irregularly arranged, with an amorphous molecular substance.

The internal granular layer is composed of two kinds of cells with nuclei. The larger of these are nerve cells, similar to those in the layer of ganglion cells, and having two offshoots, one passing into the inner granular layer to anastomose with the offshoots from the ganglionic cells and the other passing outward into the external molecular layer, where, it is claimed by some, they anastomose with fibres from the layer of rods and cones. The smaller cells of this layer are connected with the fibres of Muller.

The external molecular layer is very thin and is made up of the fibres just mentioned, together with a molecular substance similar to that of the internal molecular substance similar to that of the internal molecular layer.

The external granular layer, like the internal, is composed of both nerve and connective tissue elements. The former consists of bi-polar cells, from which offshoots pass outward to the layer of rods and cones and inward to the internal granular layer.

The external limiting membrane is the expansion formed by the terminal extremities of the fibres of Muller.

The layer of rods and cones is the most important part of the retina. The rods, commencing as fine fibres in the outer molecular layer, pass through the outer granular layer and, just beneath, the external limiting membrane, begin to increase in size, forming the rod granule, and some distance after passing through this membrane they taper down into cylindrical shaped rods, which extend outward to the pigment layer. The cones also commence as a cone-shaped swelling in the outer molecular layer, where they are in direct communication with the fibres from the internal granular layer. The cone-fibre becomes thinner until, just underneath the external limiting membrane, it again swells rapidly and there forms the cone itself, which contains a large oval nucleus and nucleolus. The cones are shorter and thicker than the rods and are of a bottle-shaped appearance. The rods and cones are arranged perpendicularly to the plane of the retina and may be divided into an inner and outer part. The inner segment is thicker than the outer and appears granulated; the outer part is broken up into fine, highly refracting lamellae, appearing like superposed circular discs or a pile of coins.

The pigment layer consists of a single layer of hexagonal nucleated cells, the inner surface of which is loaded with pigment granules.

The fibres of Muller from the connective tissue framework of the retina which traverses its various layers from the internal to the external limiting membranes and spreads out in these membranes.

The macula lutea or yellow spot is about I. 25 mm. in diameter and is the most sensitive portion of the whole retina. It lies to the outer side of the antero-posterior axis of the eyeball. The shape of the macula has been almost universally described in text-books as oval; the error of this has been pointed out by Johnson, Archiv. Ophthal., vol. xxi., I, 1892. who claims that: “The macula is invariably circular, and probably corresponds to the extreme limit of macula region,” and that it is best seen with a very weak illumination the macula ring can be seen in its entire circumference in nearly every person under thirty-five years of age and frequently over that age. He concludes that the mistake of all authors who have seen the macula has also been variously described, usually as of a somewhat yellowish appearance, from which it was called the yellow spot, but Johnson (loc. cit), by means of sixteen colored drawings, shows that “, in normal eyes of Europeans the inner portion of the macula appears of a more intense or brighter red than the fundus generally, the color deepening as it approaches the fovea centralis, where it is almost always masked by the bright foveal reflex, varying in shape and intensity.”

Anatomically the macula differs from other parts of the retina in that there are no rods, and the cones are longer and narrower than in other parts of the fundus. At the centre all the other layers of the retina are thinner, forming a depression called the fovea centralis, for toward the margin the retinal layers, especially the layer of ganglionic cells, are for the most part thicker than elsewhere.

The vascular supply of the retina is derived from the arteria centralis retinae which divides on the optic disc into an upper and lower branch. These branches then turn outward, forming a large ellipse around the macular region, none of its capillaries extending into the fovea; other branches are given off to supply the inner and other parts of the retina. Each artery is generally accompanied by a vein.

The appearance of the healthy retina is that of perfect transparency. The retinal vessels are easily distinguished from those of the choroid by being more clear and well-defined and by their taking a more radiating course and branching dichotomously. Pulsation of the retinal veins and still more rarely of the arteries may occasionally be seen in normal eyes; both may be produced by pressure of the finger upon the globe during an ophthalmoscopic examination. Usually, however, pulsation of the retinal vessels is indicative of some pathological change.

Hyperaemia Retinae-It is difficult to state in any given case whether the congestion exceeds that which is physiological or not, and in making the diagnosis the relative sizes of the arteries and veins should be considered. Normally the retinal arteries are about three-quarters the size of the corresponding vein. Hyperaemia may be either active or passive. Active hyperaemia (arterial or irritation) usually results from some straining of the eyes, such as a prolonged use of the eyes fine work or by poor light. It is often associated with or caused by some refractive error and is, or course, present in the first stage of retinitis, or may be present with inflammation of the cornea, iris, etc. The relative size of the vessels in active hyperaemia is usually well maintained and the diagnosis rests upon the congestion of the optic disc, which becomes more pinkish, with less contrast between it and the surrounding fundus. It manifests itself to the patient by fatigue on using the eyes, sensitiveness to light, pain and pressure within the eye. Passive hyperaemia (venous or stasis) results from some circulatory interference which may take place in the eye, as in glaucoma, or external to the eye, as in pressure upon the optic nerve. In this form the relative normal proportions between the arteries and veins becomes lost and we find the veins tortuous and increased in size, while the arteries may either remain normal or become diminished. In hyperaemia the only symptoms complained of by the patient will be some dimness of vision; or of flashes of light before the eyes.

TREATMENT-Hyperaemia frequently depends upon some refractive error, which should be corrected by suitable glasses. Rest of the eyes of the great importance, and hence the patient should be instructed to abstain from all use of the eyes. The remedies most frequently found of service are Dubois., Belladonna, phos., Conium, Pulsatilla or Bryonia The special indications will be found under Retinitis.

Retinitis Simplex-{ Retinitis Serosa, Retinitis Diffusa, OEdema of the Retina)

PATHOLOGY-There is hyperaemia of the retinal vessels followed by an infiltration of serous fluid into all the layers of the retina. The membrane, especially in the neighborhood of the disc, becomes somewhat swollen and thickened.

SYMPTOMS-Patients will complain of a diminution of vision as though looking through a mist, and the field of vision may be somewhat impaired. The ophthalmoscope will show a hyperaemia of the retina and optic papilla, together with a diffuse grayish of bluish appearance of the retina, especially in the vicinity of the optic disc, the outlines of which are slightly blurred and indistinct. The vessels may be slightly covered, as with a veil, or appear perfectly distinct.

CAUSES-This form of inflammation may precede or extend into other types of retinitis. It has been attributed to exposure to cold, heat or strong light, and as a result of over use of the eyes by poor light especially when there is some refractive error and in many cases it is impossible to assign a distinct cause.

PROGNOSIS.- If the disease leads to no more serious form of inflammation, recovery, with perfect restoration of vision, is the rule. Neuro-retinitis is a more common diagnosis, as the optic nerve the retina are usually inflamed at the same time.

TREATMENT-Rest is the most important aid in all cases whether inflammatory or only hyperaemic, and the more complicate it is, especially in neuritis or retinitis, the better for the patients. they should be artificial light. Some authors, Stellwag and others, recommend the confinement of the patient in a darkened room and the employment of a bandage. Such severe measures are, however, not required except in extreme cases. It is better to allow moderate exercise in the open air, taking care that the eyes are properly protected from the irritating influence of bright light by the use of either blue or smoked glasses.

Proper hygienic rules, according to the nature of the case, demand our most careful attention.

Belladonna-One of the most frequently indicated remedies for both hyperaemia and inflammation of the optic nerve and retina. the retinal vessels will be found enlarged and tortuous, particularly the veins, while a blue or bluish-gray film may seem to overspread the fundus (oedema). Extravasations of blood may be numerous or few in number. The optic disc is swollen and its outlines ill-defined. the vision is, of course, deteriorated. The pains are usually of an aching, dull character, cough may be throbbing and severe, accompanied by throbbing, corrective headaches with visibly beating carotids and flushed face. Phosphenes of every shape and hue, especially red, may be observed by the patient. Decided sensitiveness to light. The eyes feel worse in the afternoon and evening when all the symptoms are aggravated.

Duboisia-Of great value in the treatment of both hyperaemia and inflammation of the optic nerve and retina. Retinal vessels large and tortuous, especially the veins. Optic papilla swollen and outlines ill-defined (engorged papilla). Haemorrhages in the retina, aching in the eyes and pain through the upper part of the eyeball just beneath the brow, which may be very severe. Chronic hyperaemia of the conjunctiva.

Phosphorous-Hyperaemia or inflammation of the optic nerve and retina, especially with extravasations of blood. Degeneration of the coats of the blood-vessels. The eye may be sensitive to light and vision improved in twilight. vision impaired, muscae volitantes, photopsies and chromopsies are present, halo around the light. The eyeballs may be sore on motion and pain may extend from eyes to top of head.

Pulsatilla.-Hyperaemia and inflammation of the optic nerve and retina accompanied by more or less severe pains in the head always relieved in the open air. Sensation as if a veil were before the eyes, or the vision may be nearly lost. All the ophthalmoscopic appearances of engorged papilla or simple hyperaemia and be present if dependent upon menstrual difficulties or associated with acne of the face or disorders of the stomach.

Bryonia.-Serous retinitis or hyperaemia, with a bluish haze before the vision and severe sharp pain through the eye and over it. Eyes feel full and sore on motion or to touch. Great heat in the head, aggravated by stooping.

Mercurius.-Retinitis with marked nocturnal aggravation and sensitiveness of the eyes to the glare of the fire. Congested conditions of the fundus found in those who work at a forge or over fires. Degeneration of the blood-vessels, with haemorrhages into the retina. Concomitant symptoms will assist us in the selection.

Cactus.-Retinal congestion, especially if heart trouble is present.

Cactus.-Retinal congestions, especially if heart trouble is present.

Conium.-Fundus congested, with much photophobia, ciliary muscle weak.

Nux vomica-Retinitis occurring with gastric disturbances, especially in drunkards. The eye indications vary, but are usually aggravated in the morning.

Veratrum viride-Engorged disc, with severe pain at menses and general vaso-motor disturbances.

In addition to the above, the following remedies may be of benefit in rare cases or as intercurrents; Aconite, Arsenicum, Aurum, China sulph., Gels, Kali, iod, Kali mur., Lach, Spigelia and Sulph.

Dazzling of the Retina-Under this heading we shall class all those cases accompanied by a dazzling sensation, due to exposure to the bright glare of the sun, upon snow or water, to the electric light, etc. These conditions may produced a diffuse retinitis or neuro-retinitis, or, again, such exposure may be followed by amblyopia, with no ophthalmoscopic signs. Widmark Revue generale d’ophthalmologie, Paris, Aug., 1890. considers the trouble as produced by direct irritation of the part affected and that this is caused almost exclusively by the ultraviolet rays which exert a similar influence upon the skin. the patients complain of a dazzling, a central scotoma and slight impairment of the vision. Objects appear in a mist and the air seems to flicker. Cases of retinitis have also been reported as the result of a single intense flash of light. The treatment of these cases consists in the prevention of all use of the eyes and in protection from the light.

Retinitis Albuminurica- (Renal Retinitis, Papillo retinitis, Retinitis of Bright’s Disease).

PATHOLOGY-The pathological changes in albuminuric retinitis are numerous and variable in the different stages of the disease. There is at first a slight granular exudation into the retina, with a fatty degeneration of the walls of the vessels. Following this there is a hyperplasia of the connective tissue of the retina with subsequent fatty degeneration. the nerve-fibres become remarkably swollen; these swellings are club-shaped and highly refracting and the whole layer is much thickened. Later these fibres undergo fatty degeneration and atrophy. The ganglion cells may undergo a similar degeneration or remain unaltered. The granular layer become infiltrated and thickened and pass into a fatty degeneration. Haemorrhages, which result from the degenerated walls of the retinal vessels, may occur at any place, but are found most numerous in the nerve-fibre layer, and serve to increase the destruction of the retinal elements. there may be a slight proliferation of pigment, but this layer is but little affected. There are usually found pathological changes in the choroid, nerve, and other parts of the eye. According to Weeks, Archiv. Ophthal., vol. xvii., 3, 1888. we may divide this disease into two classes of cases-those occurring in all forms of acute disease of the kidneys, such as pregnancy, scarlet fever, and, in the other class, he places those dependent upon a general diseased condition of the vessels in which the eye symptoms precede those of the kidney. In the first form, which is by far the most frequent, oedema and white patches appear first, to be followed by haemorrhages, while in the second class a slight haemorrhage near the macula and a few bright dots are the first evidenced, followed later by the oedema and white patches.

SYMPTOMS-The only subjective symptoms noticed by the patient is that of impairment of vision, which may vary from a slight cloudiness to complete blindness. The field of vision and also the color vision remains good. Frequently the disease is diagnosed by ophthalmoscope before the patient is aware that there is seen swelling and hyperaemia of the disc; the retinal arteries are somewhat diminished and the veins increased in size; there is a diffuse haziness of the retina, together with haemorrhage and the formation of white patches.

In a well-marked case there is in the macula or its immediate vicinity numerous fine white spots, which are, in the early stages, small and separate, but later on, or a truly typical case, from a star-shaped figure, at the centre of which lies the fovea centralis. These specks are due to the infiltration with fat of Muller`s fibres. Other of these spots and somewhat larger in size, due to the fatty degeneration of the two granular layers, are usually seen around the papilla, and in this locality they will often coalesce into a broad zone around the optic nerve entrance, giving it he appearance usually designated as surrounded by a snow bank. These peculiar white spots of the retina are due to a fatty degeneration of the nerve-fibre and granular layers, and, when seen, may be considered almost pathognomonic of albuminuria, particularly so when assuming the star-shaped arrangement at the macula.

The white patches occur mostly in the deeper layers of the retina, as proven by the fact that the retinal vessels may usually be seen passing over them, but may be partially or completely covered by the patch at some places.

Haemorrhages are almost universally found in albuminuric retinitis, but unlike the white patches just described, are not especially pathognomonic of this disease. They may occur in great numbers and of various sizes and shapes, from large, dark- red extravasations to small, round or linear-shaped spots scattered throughout the fundus. Haemorrhages occurring in the nerve fibre layer are striated in appearance. The extent of the haemorrhages is considered to be somewhat indicative of the severity of the disease.

COURSE-When due to pregnancy, diphtheria, or scarlet fever, is comparatively short, but when dependent upon the contracted kidney it is very chronic. Albuminuric retinitis may either gradually or suddenly pass into a neuro-retinitis resembling very closely the choked disc from cerebral causes. The ophthalmoscope picture of retinitis albuminurica (See Chromo-Lithograph, Plate II, Fig.6) may remain unaltered for a long time, the haemorrhages and white patches slowly disappearing, while new ones at the same time may make their appearance. The white plaques at the macula are always the last to disappear, and, may never, according to some authorities. As the secondary changes go on the optic disc becomes discolored and atrophied, the retinal vessels become contracted and pigment changes in the retina result.

CAUSES-Renal retinitis may occur with any form of kidney disease, but is especially found with the contracted kidney. It is also quite frequently seen associated with the albuminuria of pregnancy, and more rarely with post scarlatinal nephritis. A few cases have also been reported associated with functional albuminuria. Both eyes are as a rule involved, although it may occur in but one.

DIAGNOSIS-The ophthalmoscopic appearances are always quite characteristic of this disease, and the presence or albumin in the urine would at once confirm the diagnosis. Diabetic and leukaemic retinitis both present appearances of the fundus very similar to those found in this disease, and an examination of the urine will be necessary to clear up the diagnosis. A neuro- retinitis resulting from intra-cranial disease, especially if it be complicated by albuminuria, would present great difficulty in the differential diagnosis and a very careful study of the general symptoms would be required. The white spots in choroidal affections would differ from this by presence of more or less pigment and by the different location and shape of the white patches. Opaque optic nerve-fibres resemble somewhat closely the snow-bank appearance around the papilla, but in opaque nerve- fibres the white patches extend out from the disc in a fan-shaped manner, it is unaccompanied by any change in the macula or oedema of the retina and the vision is but little or none affected.

PROGNOSIS-In albuminuric retinitis the prognosis must necessarily cover two points; first, as to vision, and second, as to the life of the patient. The prognosis as to vision should always be unfavorable, excepting in the slighter cases and particularly those occurring in pregnancy. The appearance of albuminuric retinitis in all cases, excepting when associated with pregnancy, is always a most unfavorable symptom as regards the life of the patient. It is extremely rare for recovery to take place in cases of kidney disease after the retina has become involved, and in the majority of cases a fatal termination will ensue inside of two years.

In the retinitis albuminurica of pregnancy the prognosis depends chiefly upon the period of gestation, and secondly upon the extend of the disease. Some cases of very extensive haemorrhages, with marked patches of infiltration of the retina and almost complete loss of vision, when only occurring in the last weeks of pregnancy, may recover, after confinement at full term, with almost complete restoration of vision. On the other hand, slight changes in the earlier months of pregnancy, which have a tendency to increase in spite of treatment, may prove very serious both o vision and the life of the patient as w3ell, if allowed to go on to full term, The longer the disease exists the greater are the degenerative changes which may take place, and it is on this account that the appearance of the disease in the last weeks of pregnancy proves far less serious than when occurring early. Induction of premature delivery in these cases becomes then a question of grave importance. The presence of albuminuric retinitis, when of a high degree and accompanied by loss of sight, denoting advanced degeneration of the kidneys, together with the face that the uraemic condition of the blood, threatens the life of both mother and foetus, to us argues in favor of interference. Howe draws the conclusion that ” The induction of labor is warrantable when the retinitis appears in the early stage of pregnancy and persists in spite of -proper treatment, but is not warrantable in the last few weeks, in spite of the greater case with which it is accomplished, unless the inflammation is unusually severe.”

A. B. Norton
Norton, A. B. (Arthur Brigham), 1856-1919
Professor of Ophthalmology in the College of the New York Ophthalmic Hospital; Surgeon to the New York Ophthalmic Hospital. Visiting Oculist to the Laura Franklin Free Hospital for Children; Ex-President American Homoeopathic Ophthalmological, Otological and Laryngological Society. First Vice-President American Institute of Homoeopathy : President Homoeopathic Medical Society of the State of New York ; Editor Homoeopathic Eye. Ear and Throat Journal : Associate Editor. Department of Ophthalmology, North American Journal of Homoeopathy, etc.