N. Y. (STATE), COMMISSION FOR THE BLIND. 
THE EYE; ITS IMPORTANCE IN RELATION 
TO GENERAL DISEASE. THE EYE AND ITS IMPORTANCE 
IN RELATION TO GENERAL DISEASE 
Conrad Berens, M.D. 
and 
Adolph Posner, M.D. 
JULY 1949 
Prevention of Blindness Service 
COMMISSION FOR THE BUND 
STATE DEPARTMENT OF SOCIAL WELFARE 
205 East 42nd Street 
New York 17, New York THE EYE AND ITS IMPORTANCE 
IN RELATION TO GENERAL DISEASE* 
Conrad Berens, M.D. 
and 
Adolph Posner, M.D. 
It has been long recognized that the state of health of the body as 
a whole has a definite effect on the health of the eyes. The following 
pages have been prepared in an attempt to clarify the relationship 
between general diseases and eye diseases for the reader who has no 
specialized knowledge in the field of ophthalmology. 
In man and the higher animals the eye represents an expanded and 
specialized portion of the brain. Therefore, certain diseases of the 
brain can often be recognized through a study of the eyes. The eye 
is also the one place in the body where blood vessels are not covered 
by opaque tissues; not only are they exposed to direct view, but they 
may be observed under a magnification of approximately 15 times 
their natural size. Since many diseases affect all the blood vessels of 
the body to nearly an equal degree, a study of the blood vessels of 
the eye often permits an early diagnosis of such diseases as arterio- 
sclerosis (hardening of the arteries), hypertension (high blood pres- 
sure), nephritis (kidney disease), diabetes (excess of sugar in the 
blood), and the group of blood diseases named the leukemias, which 
are characterized by the presence in the blood of an excessive number 
of white blood corpuscles. 
Gross Anatomy of the Eye (Figs. 1 and 2) 
A knowledge of the anatomy and embryology of the eye is vital 
to an understanding of the eye in relation to general diseases. A brief 
discussion follows of the structures which compose the eyeball and 
are closely associated with it: the cornea, the three coats of the eyeball, 
the optic nerve, the crystalline lens, the vitreous and aqueous humor, 
the eyelids, the conjunctiva or modified skin lining the eyelids, the 
lacrimal apparatus which produces and drains the tears, and the 
extraocular muscles. 
* Aided by a grant from The Ophthalmological Foundation, Inc. 
3 Fig. 1 — Sagittal Section through the Eyeball and Eyelids. 
A — sclera; B — choroid; C — retina; D — optic nerve; E — sheath of optic nerve; 
F —vitreous; G —lens; H —inferior rectus; I — ciliary body; J —iris; K — 
cornea; L — Meibomian gland; M — tarsus; N — conjunctiva; O — orbicularia 
muscle; P — skin of the eyelid; Q — levator palpebrae superioris; R — superior 
rectus muscle. 
The cornea (window of the eye) is the curved, transparent, tough 
membrane which constitutes the front of the eyeball. It allows the 
light to pass through, but protects the contents. 
The sclera, commonly called the white of the eye, forms the protec- 
tive outer coat of the eyeball, and affords attachment for the external 
muscles which make it possible for the eye to turn in the various 
directions. 
The vascular or second coat of the eye (uveal tract) is the layer 
which lies directly beneath the sclera. It contains the blood vessels 
that nourish the interior of the eye. This layer consists of three dis- 
tinct parts which differ structurally from one another. They are: 
4 Fig. 2 — Greatly magnified section of the front portion of the eye ball: A — 
cornea; B —iris; C — lens; D — sphincter muscle of the iris, which causes the 
pupil to contract; E — Schlemm’s canal; F — angle of the anterior chamber; 
G — ciliary muscle; H — vitreous. 
the iris, the bulk of the ciliary body and the choroid. The iris, which 
is formed of the blood vessel layer and a background of pigmented 
cells, encloses a round opening which is the pupil. The color of the 
iris varies in different individuals from blue to gray and brown. The 
pupil is situated at the center of the iris for the transmission of light. 
The ciliary body (Fig. 2) contains the muscles which make it pos- 
sible for the eye to focus. The choroid lines the greater part of the 
eyeball and serves as a source of nourishment for the rods and cones 
of the retina. 
The retina, or nerve coat, is the innermost coat of the eye. Its func- 
tion is to receive the light rays, which produce an inverted image of 
the observed object. This image is then carried by the optic nerve 
to the brain, where it is turned right side up and interpreted. 
5 The optic nerve is a relatively thick stem which connects the eye 
with the brain. It is composed of many individual nerves, each one 
covered by a sheath and all of them bound together by strong con- 
nective tissue fibers. The optic nerve itself is surrounded by three 
sheaths, which are continuous with the sheaths of the brain. 
The crystalline lens is the transparent structure behind the pupil 
which focuses light rays on the retina. It corresponds to, and has prac- 
tically the same shape as, the lens in the camera. The crystalline lens 
has no blood vessels, but is nourished by the fluids (vitreous and aque- 
ous humor) surrounding it. It is made up of many concentrically 
arranged cells and the lens grows continually throughout life by the 
lengthening of these cells. 
The vitreous is a substance resembling the white of an egg, which 
fills the space back of the lens and maintains the shape of the eye. 
If its nutrition is disturbed or chronic infection attacks the blood 
vessel coat of the eye, the vitreous becomes cloudy and the patient 
is aware of floating spots or strands. Under these circumstances the 
vitreous may also lose its gelatinous consistency, becoming fluid. 
The aqueous humor is the watery liquid that fills the front portion 
of the eyeball between the cornea and the lens. It is secreted by the 
ciliary body behind the iris. The aqueous humor passes through the 
pupil and leaves the eye in front of the iris, through the angle between 
the iris and the cornea where it is drained off through the canal of 
Schlemm and the aqueous veins. Interference with its circulation gives 
rise to increased hardness of the eyeball, a condition known as 
glaucoma. 
The eyelids are composed of several layers of tissue. Beneath the 
outer skin is the muscle that opens and closes the eyelid. This muscle 
overlies the tarsus, which is a plate of dense fibrous tissue that gives 
the eyelid its shape. The tarsus contains the meibomian or grease 
glands, and provides an attachment to the muscles which move the 
eyelids. 
The conjunctiva is the modified skin that lines the inside of the eye- 
lids and extends over the anterior one-third of the eyeball. It is com- 
posed of an outer layer of epithelial cells which differ from the epi- 
thelial cells of the skin because they do not have a horny substance. 
The lacrimal apparatus is a system of glands and ducts concerned 
with the circulation of tear fluid. The lacrimal gland, which produces 
the tears, is situated beneath the outer portion of the eyebrow. Its 
6 Fig. 3 — The Lacrimal Apparatus: A — lacrimal gland; B — ducts of the lacrimal 
gland; C — puncta (upper and lower); D— canaliculus; E — lacrimal sac; 
F — nasolacrimal duct; G — Meibomian glands contained within the tarsal plate. 
delicate ducts empty into the upper fornix, or fold of the conjunctiva. 
After having discharged its functions of lubricating and cleansing 
the surface of the cornea, the tear fluid is drained off through the 
puncta, or small holes, one being located near the nasal corner of each 
eyelid. From here, the tears pass through narrow ducts (canaliculi) to 
the lacrimal sac, which carry them to the nasolacrimal duct and finally 
into the nasal cavity. This system of canals accounts for the fact that 
medicine instilled in the eye is often recovered in the nose and throat. 
The muscles which turn the eyeball are six in number, four recti 
or straight muscles and two oblique muscles. The four recti muscles 
(Fig. 4) are; (A) the medial rectus muscle, which turns the eyeball 
toward the nose; (B) the inferior rectus muscle, which turns the eye- 
ball downward; (C) the lateral rectus, which turns the -eyeball to- 
ward the temple; and (D) the superior rectus, which turns the eyeball 
upward. The two oblique muscles are: (E) the superior oblique, 
which, from the primary position, turns the eyeball downward and 
outward but rotates the eyeball downward when the eye is turned 
7 Fig. 4 — Extraocular Muscles. A —medial rectus muscle; B —inferior rectus 
muscle; C — lateral rectus muscle; D — superior rectus muscle; E — superior 
oblique muscle; F — inferior oblique muscle. 
inward; and (F) the inferior oblique muscle, which, from the primary 
position, turns the eyeball upward and outward but rotates the eyeball 
upward when the eye is turned nasally. 
Embryologic Development of the Eye 
The eyeball develops from an out-pouching of the brain which 
projects forward on either side of the head to form the primary 
optic vesicle (Fig, 5A). This pouch or vesicle consists of a thin layer 
of tissue from which the retina develops. 
In shape, the young human embryo resembles a little tadpole (Fig. 
5B). On the back of this embryo a groove develops by the infolding 
of the outer layer or primitive skin. This groove is called the neural 
groove because it gives rise to the nervous system. The edges of the 
neural groove unite, thus forming the neural canal. This closure begins 
8 Fig. 5A —Forebrain and optic vesicle on one side of embryo, shown in section. 
1 — forebrain; 2 — optic stalk (later the optic nerve); 3 — primary optic vesicle 
(later the eyeball). (After Mann.) 
Fig. 5B — Superficial view of young human embryo; 1 — neural groove; 2 — 
neural canal; 3 — primitive brain; 4 — optic pit. (After Mann.) 
in the middle of the embryo and progresses forward and backward. 
The open front portion of the neural groove meanwhile commences 
to form little pouches, separated by indentations, thus marking off 
the divisions of the brain. In one of these pouches there appears on 
each side a depression, the optic pit (Fig. 6A), which grows out to 
form a grape-like vesicle, the primary optic vesicle (Fig. 6B). From 
this vesicle the eyeball is formed. The vesicle remains attached to 
the brain by means of a stalk which becomes the optic nerve. The 
optic vesicle comes into close contact with the layer of primitive skin. 
At this point a thickening forms in the skin; this is the lens plaque. 
This plaque pushes the optic vesicle in and becomes the lens groove, 
which, by detaching itself from the rest of the skin, becomes the 
lens vesicle. The lens vesicle becomes filled with cells and fibers and 
eventually develops into the lens of the eye. The optic cup. now has 
two layers; the inner layer forms the visual or seeing portion of the 
retina, while the outer layer acquires pigment (layer of pigmented 
epithelium) and serves as a light-proof background for the retina. 
From the inner layer of the retina, fibers grow toward the optic 
stalk and thence to the brain. This bundle of nerve fibers is known as 
9 Fig. 6A — Section through front portion of human embryo: 1 — neural groove; 
2 — primitive skin; 3 — optic pit. (After Salzmann.) 
Fig. 6B — Sagittal section through primary optic vesicle: 1 — primary optic 
vesicle; 2 — cavity of primitive brain; 3 — optic stalk; 4 — primitive skin; 
5 — lens plaque showing transition to lens groove. (After Salzmann.) 
the optic nerve. These stages in the development of the eye are dia- 
grammatically represented in figure 7. 
Surrounding the optic cup is a mass of tissue which condenses to 
form the tough outer coat of the eye (the sclera), the front part of 
which remains transparent to form the cornea or the window of the 
eye. Other portions of this tissue differentiate to form the iris (the 
Fig. 7 — Diagrammatic representation of the development of the primitive 
human eye: 1 —cavity of forebrain; 2—cavity of optic vesicle; 3—cavity of 
optic vesicle becoming obliterated by formation of optic cup; 4 —optic cup 
well formed; 5 — two layers of optic cup; 6 —optic stalk; 7 — optic nerve 
developing. (After Mann.) 
10 diaphragm of the eye) enclosing a round opening, the pupil, and the 
ciliary body with its muscle which acts on the lens to make it focus 
the image sharply on the retina. 
The under surface of the optic cup remains open forming a groove. 
Through this groove two blood vessels, a vein and an artery enter 
the optic cup just before the groove closes. T hese vessels form the 
central vein and artery of the retina (see Fig. 12). 
Anatomical Relation of the Eye and Body 
We have seen from the discussion on embryology of the eye that 
there is an intimate relation between the eye and the brain. However, 
we must also be aware of the fact that the eye as a part of the body is 
Fig. 8 — Schematic drawing of a horizontal section through the right orbit to 
illustrate the relation of the nasal sinuses to the eye. A — nasal cavity; B — 
ethmoid cell; C — anterior ethmoid cells; D — posterior ethmoid cells; E — 
sphenoid sinus; F — orbit; G — eyeball; H — lateral wall of the orbit; I — optic 
nerve; J — optic foramen; K — intracranial portion of optic nerve; L — nasal 
septum. 
11 connected with the general blood vessel system and with the lymphatic 
system which includes glands, vessels, sinuses, and spaces as well as 
serous membranes. 
The most intimate association that the eye has with the body is in 
relation to the sinuses of the nose (see Fig. 8). On both sides of the 
nasal septum (the tissue dividing the nose into two cavities), the 
turbinate bones protrude like flaps into the nasal cavities from the 
inner walls of the orbits. In the wall of the orbit are the ethmoid cells, 
consisting of an anterior and a posterior group on each side. Behind 
them is the sphenoid sinus, closely adjoining the optic nerve. It is 
easy to understand that an inflammation of the sphenoid sinus may 
cause an inflammation of that portion of the optic nerve which is 
situated behind the eyeball. 
The close connection that exists between the eye and the sinuses 
through the many veins and lymphatic vessels (the latter carry color- 
less fluid and white blood cells) makes it possible for any part of the 
eyeball to be involved when there is an inflammation of the nasal 
passages or sinuses. 
EYE SYMPTOMS SUGGESTIVE OF GENERAL DISEASES 
Let us now consider the symptoms which lead us to suspect an 
abnormal condition of the eye, and also attempt to deduce any 
relationship which may exist between eye symptoms and general 
symptoms. 
(1) Eyestrain and Headache. A majority of the people suffering 
from headache attribute it to eyestrain and the first step usually is to 
consult an eye physician. Although headache may arise from various 
diseases, the oculist should always endeavor to exclude the eye as a 
factor because it is a dangerous practice to diagnose the cause of a 
headache from its location and character alone. 
What is an eye headache? There is no typical eye headache but the 
following characteristics should lead one to consider the eyes as the 
probable cause of the headache: a headache which is brought on or 
aggravated by the use of the eyes; a headache located over the eyes, 
or around the eyes, or sometimes radiating down the back of the neck. 
However, even in apparently typical cases, we must not overlook the 
fact that other conditions may cause the headache. The time of occur- 
rence is an important factor. If the patient awakens in the morning 
with headache around the eyes, or above the eyes, and feels better after 
being up for a while, the headache may be caused by infection of the 
nasal sinuses. 
12 A headache which radiates down the back of the neck is often 
attributable to faulty coordination of the eye muscles. If it is difficult 
for the patient to focus his eyes for a long time on close objects, the 
condition is called weakness of convergence or convergence insuffi- 
ciency. This is a common finding and one of the most frequent causes 
of difficulty in using the eyes. This condition is often observed in chil- 
dren who return to school having had no occasion for using their eyes 
for close work all summer. It is due to rapid fatigue or weakness of 
the coordinating centers of the ocular muscles. 
Headaches may also arise from a systemic infection, viz., infection 
in the sinuses or intestinal tract, or from excessive mental strain. If 
headache persists for a long time, other causes, such as migraine, and 
increased pressure in the brain following a brain tumor or a head 
injury, should be ruled out. 
(2) Photophobia. We see many children who complain of fear of 
the light. What is the significance of this symptom? Photophobia may 
be caused by inflammation of the iris or cornea, or it may be due to 
irritation of the conjunctiva (the membrane lining the eyelids), or to 
inflammation along the borders of the eyelids. Photophobia may even 
signify the need of proper eye glasses, for the excessive use of the 
muscles of the eye entails a great strain which gives rise to congestion 
and irritation which in turn produces photophobia. But fear of light 
is also commonly due to causes remote from the eyes, namely, general 
infection or focal infection. The focus may be situated in the teeth, 
tonsils, sinuses, intestines, and other parts of the body. 
(3) Lacrimation. Tearing is common and may arise from a simple 
local condition such as narrow, malplaced or blocked drainage chan- 
nels from the eye, but quite often this is not the case. Among causes 
outside the eye is nervous stimulation of the tear gland. Since tear- 
ing may be associated with chronic nasal infection, anyone who is 
constantly troubled with tearing should have his nose and sinuses 
examined. In infants tearing may indicate that the tear passages into 
the nose failed to open. This condition is often cured by passing 
a probe through the tear duct. 
(4) Diplopia. Double vision may be monocular or binocular, de- 
pending upon whether the patient sees double when using' one eye 
alone, or only when using both eyes together. The latter is the type 
in which we are most interested as it is sometimes due to serious 
disease. Temporary attacks of double vision, occasionally encountered 
in school children, may be due to hysteria or to transient disorders of 
13 the eye muscles. However, too often double vision indicates disease 
of the brain (for example, brain tumor, epidemic encephalitis, menin- 
gitis and syphilis) or, in older people, disease of the arteries (arterio- 
sclerosis) . 
(5) Congestion of the borders of the eyelids. This is a common 
complaint. It may be due to local causes, but frequently it is associated 
with other infections, especially with sinusitis and infection of the 
scalp. 
(6) Failing Distant Vision. If this symptom is present in a young 
person attending school, it is probably due to the fact that he is be- 
coming slightly near-sighted. Near-sightedness can be corrected by 
wearing appropriate eyeglasses. If distant vision fails in the adult, it 
is commonly due to the fact that he is unable to compensate for a 
far-sighted condition (hyperopia) because of an increasing loss in 
the elasticity of the lens (presbyopia). However, cataract (clouding 
of the lens), glaucoma (hardening of the eyeball), and other chronic 
diseases of the eye should also be considered as possible causes. 
Poisoning by tobacco, alcohol and arsenic may cause neuritis of 
the nerve back of the eyeball (retrobulbar neuritis) resulting in dis- 
turbance of vision. Diabetes and nephritis may disturb vision as the 
result of changes in the retina (diabetic and renal retinopathy). 
(7) Failing Near Vision. In the adult the vision for near normally 
begins to fail after the age of about 45 years. This is due to loss of 
elasticity of the lens. The same symptom in a child often indicates 
that he is commencing to be troubled by far-sightedness (hyperopia). 
These patients are benefited by properly fitted glasses. Sometimes fail- 
ing near vision may signalize a more serious condition. It may mean 
the early stage of sympathetic ophthalmia (inflammation of a healthy 
eye due to injury of the other) or it may be an early sign of glau- 
coma. Weakness of accommodation due to diphtheria, anemia, hypo- 
thyroidism and syphilis may cause difficulty in reading or other 
near work. 
(8) Halos. Seeing colored rings or halos around lights is a com- 
mon sign in glaucoma. It may also be due to inflammation of the 
cornea, or to an early stage of cataract, or even to toxic conditions. 
(9) Nyctalopia. Night blindness is sometimes due to a dietary 
deficiency, that is, insufficient vitamins in the diet. At other times it is 
the chief symptom of a disease known as retinitis pigmentosa which 
may be hereditary or result from syphilis (syphilitic chorio-retinitis). 
14 (10) Micropsia a?id Macropsia. Micropsia is seeing things smaller 
than they are and macropsia means seeing things larger than they are. 
In the exact center of the seeing layer of the retina in the back of the 
eye there is a spot where vision is most acute — the yellow spot or 
macula lutea. The apparent size of an object depends upon the number 
of seeing elements in the retina upon which the image of this object 
falls. If the yellow spot becomes swollen, fewer elements are stimu- 
lated and the object appears smaller. If there is a depression in this 
region, more elements are exposed and the object appears larger. This 
is a very ominous sign because any disease of the macula lutea is 
serious and, if possible, an attempt should be made to find the cause. 
Certain Diseases of the Eye Associated with General Diseases 
It is important to realize that many disturbances of the eye may be 
the result of serious general disease. Moreover, an eye symptom should 
not be neglected and when in doubt an oculist should be consulted. 
Herpes Zoster Ophthalmicus. Herpes Zoster or shingles is a dis- 
ease of the sensory nerve. It may affect any nerve. It becomes of inter- 
est to the eye physician when it affects the ophthalmic division of 
the fifth nerve which goes to the eye. Clinically, the disease consists 
of blisters surrounded by an area of inflammation. The most striking 
feature of this affection is the severe pain which usually precedes the 
appearance of the blisters. The blisters break, leaving permanently 
depressed scars. This disease is due to a filterable virus (an organism 
which is too small to be seen with the microscope and which passes 
through a bacterial filter). Since the infection must have a portal of 
entry into the body, we should investigate more carefully the sinuses 
which many observers consider of prime importance in this infection. 
The treatment of shingles is largely palliative, consisting of ointments 
and lotions. 
Convergent Squint or Crossed Eyes. As soon as a child is known 
to have squint, he should be examined by an eye physician. If the 
child uses only one eye, he is using only about one-half of his brain. 
Using both eyes together he develops both sides of his brain. If one 
eye is used to the exclusion of the other the vision fails in the unused 
eye. 
Squint may be caused by a serious disease of the brain, the eye, the 
nervous system, or the nerves of the eye, and a diagnosis can be made 
only after a thorough examination. A popular belief, which has been 
shown to be erroneous, is that a child cannot wear glasses until the age 
15 of three or four years. Glasses can be worn by children a year old or 
even younger. 
Another fallacy is the belief that these children cannot be operated 
upon until they are 13 or 14 years old. One should consider the psy- 
chologic handicap under which these children labor if operation is 
delayed until they are “teen-agers.” This is only one of the reasons why 
we should operate early (e.g., at three to four years of age). But 
probably the most important reason lies in the fact that if the eye 
doctor succeeds in straightening the eyes at an early age by exercise, 
glasses or operation, both sides of the brain are permitted to develop 
simultaneously. / 
Divergent Squint or Wall Eye. This type of squint, in which the 
eyes turn outward, is less common than crossed eyes and may at times 
be corrected by properly adjusted glasses for myopia (near-sighted- 
ness). One should always search for other possible underlying causes, 
such as malnutrition, disease of the brain, of the deeper parts of the 
eye, or of the other skeletal muscles of the body. When it becomes 
apparent that non-operative measures will not suffice, operation should 
not be delayed. 
Chalazion. A chalazion is a tumor or lump in the eyelid due to an 
infection of one of the Meibomian glands. Here, too, other causes 
outside the eye are sometimes responsible. Recurring multiple chalazia 
with chronically inflamed eyelids are frequently associated with an 
infection in the nose. If the cause can be removed, the treatment is 
facilitated. Because it is an inflammatory swelling it will sometimes 
subside spontaneously. If it is painful, it should be opened and treated 
like an abscess in any other location. Occasionally eye drops instilled 
into the eye will aid in the medical cure by opening the ducts and 
permitting the retained secretion to be discharged. It is also important 
to treat the other Meibomian glands, for enlargement of one gland 
usually means that many other glands are involved. Therefore, the 
eyelids should be treated regularly in order to prevent a recurrence 
of this condition. 
Dacryocystitis (inflammation of the tear sac). If we recall the 
anatomy of the lacrimal apparatus, we know that the tears are drained 
through the tear sac and the tear duct into the nose. Along its entire 
course this duct is in close relation to the sinuses. It is for this reason 
that tearing often accompanies sinus infections. The tearing is pro- 
duced by a diminished outflow due to the constriction of the tear duct 
combined with an increased secretion caused by an irritation of the 
16 nerves which supply both the sinuses and the tear glands. Therefore 
in most of these cases the underlying causes must be treated. The con- 
dition may sometimes be relieved by passing a probe down through 
the tear duct, but this form of treatment should be used only as a last 
resort, since probing may cause an injury to the lining membrane of 
the duct and thus give rise to a much more serious condition than the 
original one. 
Phlyctenular Keratoconjunctivitis (pimples and ulcers on the cor- 
nea and conjunctiva). This condition is characterized by an inflam- 
mation of the conjunctiva (the lining membrane of the eyelids) and 
of the cornea. Its cause has not been definitely determined. It is often 
associated with marked eczema of the scalp. The eye lesions consist 
of little pimples*on the conjunctiva and cornea, and most character- 
istically at the border between the conjunctiva and cornea. Children 
affected by this disease often suffer also from chronic nasal catarrh. 
For this reason and others, certain oculists are beginning to attribute 
it to chronic infections in the nose. From experiments on animals cer- 
tain workers have been led to attribute this disease to other factors, 
such as an excess of sugar in the diet and other dietary faults. In many 
instances it is caused by tuberculosis, but the essential point is not to 
overlook any of the possible factors. 
Gonorrheal Conjunctivitis in the Nenvborn. This disease is also 
known as ophthalmia neonatorum. This name, however, is mislead- 
ing, for all ophthalmia (that is, inflammation of the eye) in the new- 
born is not due to gonococci. It is true that the gonorrheal variety is 
the one which usually leads to the most serious consequences, but 
many cases are caused by one or the other of the numerous ordinary 
bacteria. Fortunately, through the work of the National Society for 
the Prevention of Blindness and other similar societies and organiza- 
tions throughout the world, ophthalmia neonatorum has been success- 
fully controlled. 
Interstitial Keratitis. This is an inflammation of the cornea, usually 
due to congenital syphilis. It may begin in one eye, but sooner or later 
involves the other as well, regardless of the type of treatment em- 
ployed. In fact it has been noted that during the course of active treat- 
ment with arsenicals, when only one eye was affected, the disease 
would appear in the other healthy eye. The introduction of penicillin 
and similar antibiotics, may offer a better chance for the control of 
this condition. It is encouraging to know that no matter how serious 
the disease may appear to be in its acute stage, it can usually be ameli- 
orated, and very frequently practically normal vision may be restored. 
17 It is essential to the proper understanding of this condition to bear 
in mind that the patient with interstitial keratitis may also have a dental 
infection, or intestinal trouble, which may act as a contributing cause. 
Scleritis. This is an inflammation of the sclera (the tough outer coat 
of the eyeball) and is characterized by a nodule in the sclera. It 
may be situated superficially, in the episclera, in which case the in- 
flammation is called episcleritis. If it is located more deeply, it is 
diagnosed as a true deep scleritis. Some believe that this disease is 
always due to tuberculosis. We are convinced that it may be due to 
syphilis, and that it may also be due to other chronic infections, the 
so-called focal infections. If this condition is permitted to progress 
without proper treatment the whole eyeball may become involved and 
be permanently damaged. 
Iritis (inflammation of the iris). The usual symptoms of iritis are 
pain in the eye, fear of light, tearing and dimness of vision. The in- 
flamed iris appears dull and of a somewhat different color than its 
normal mate; the pupil is contracted and irregular, and there is red- 
ness of the conjunctiva, especially in the region surrounding the cor- 
nea. When examined carefully through a magnifying glass, the iris 
shows markedly congested blood vessels. 
The end result of an inflammation of the iris is shown in figure 9A. 
lire lens or magnifying glass of the eye becomes opaque; the iris is 
bound down to the lens and hardening of the eyeball or glaucoma 
results. Sometimes the pupil is covered by a membrane so thick that 
it causes blindness and has to be cut in order to enable the patient to 
see. 
Among the causes of iritis, tuberculosis ranks quite high. However, 
it has occurred in association with syphilis, rheumatism, gonorrhea, dia- 
betes, dental infection, nasal disease and many other general infections. 
The early recognition of iritis is important and the patient should 
be kept under careful observation and treatment for a long period of 
time. Treatment consists chiefly in attempting to dilate the pupil and 
keeping it dilated with atropine (belladonna). As the pupil dilates we 
may notice (Fig. 9B) that portions of the tissue of the iris are still 
adherent to the anterior surface of the lens. The adhesions, when fresh, 
are usually broken up by simple treatment. If they fail to break, 
new adhesions form with repeated inflammations, until the entire bor- 
der of the iris becomes bound down to the lens, and the pupil is often 
covered by a membrane. Thus, the end result of an untreated iritis 
may be a blind eye which might have been saved by early and proper 
treatment. It is important to realize that an inflammation surrounding 
18 Fig. 9A — The end-result of iritis. 1 — lens covered by a dense white membrane 
which is opaque to light; 2 — iris bound down to lens along the entire pupillary 
and bulging forward due to increased pressure behind. 
Fig. 9B — Iris was dilated with atropine. 1 — strands of iris tissue adherent to 
anterior surface of the lens (posterior synechiae). 
the cornea or window of the eye may be the result of a serious general 
disease and an eye physician should be consulted. 
Glauco?m. The name glaucoma is applied to a symptom present in 
many eye diseases, namely an increase in the pressure within the eye- 
ball resulting in increased hardness of the eyeball (raised tension). The 
increased pressure in the eye is due to a decreased flow of the fluids out 
of the eyeball through the exit channels. The optic nerve in advanced 
glaucoma (Fig. 10) is deeply cupped. This is in marked contract to the 
normal optic disk as shown in figure 12, which lies on the same level 
19 Fig. 10 —Optic disk in glaucoma (schematic). The drawing illustrates the cup- 
shaped depression of the disk; A — with reference to the rest of the fundus B — 
the sharp margin C — of the optic nerve projects into the lumen of the cup and 
the blood vessels D — bend sharply outward as they emerge from the cup. 
as the rest of the fundus. The blood vessels in glaucoma are seen to 
cross over the edge and bend outward. This cupping may be pro- 
duced partly by increased pressure in the eyeball, partly by inflam- 
mation, resulting in damage to, and disappearance of the fibers of the 
optic nerve (atrophy). 
Glaucoma may occur in infants (congenital glaucoma). This is due 
to poor development or blocking of the outlet channels of the eye and 
occasionally to a prenatal inflammation. Since secretion continues in 
the eyeball, although the outflow is blocked, the pressure must rise, 
the coats of the eyeball stretch and the eye enlarges to the proportion 
of the so-called “ox-eye” (buphthalmos). 
In the adult we encounter two varieties of glaucoma: (1) primary 
glaucoma, the cause of which is not definitely known, and (2) sec- 
20 ondary glaucoma which has a definite cause and which is usually the 
result of an inflammation of the iris or choroid. There are two types 
of primary glaucoma: (a) the noncongestive type or glaucoma sim- 
plex and (b) congestive glaucoma. Primary glaucoma may also be 
divided into acute and chronic types. In acute glaucoma the eye be- 
comes markedly inflamed and painful. Although we are ignorant of 
the cause in most instances, we believe that an intestinal or other focal 
infection often initiates an attack. An intense emotional disturbance 
may also be a precipitating cause. Chronic primary glaucoma consti- 
tutes the larger and hence the more important group. Frequently a 
patient will not consult an eye physician until he becomes aware that 
he bumps into objects or has difficulty in walking or driving. This is 
explained by the fact that he has lost side or peripheral vision, while 
his central vision may still be unimpaired. This is a late stage of the 
disease. It is important to detect glaucoma in its early stage when 
diagnosis is often difficult. In chronic primary glaucoma the eyeball 
may be hard over a long period of time without the patient being 
aware of it. 
The old statement that “glaucoma is a sick eye in a sick body” is 
being better understood every day. Therefore, in every case of hard- 
ening of the eyeball we must look for general causes. There is the 
possibility of chronic infection acting on the thyroid and adrenal 
glands. It is often valuable to have a determination of the blood chem- 
istry made. In any event, when we study these eye conditions care- 
fully, we usually find some other causes which may be responsible for 
them. There may be, and usually are, nervous factors influencing these 
conditions. The encouraging fact about glaucoma is that we are in- 
creasingly studying it more from the psychologic, the chemical, the 
glandular and other general aspects. 
The following suggestions should be helpful to patients who have 
glaucoma: 
1. Put the drops prescribed by your eye doctor into your eyes 
regularly according to the schedule advised by the doctor, 
2. Do not use belladonna (or atropine) in any form unless your 
eye doctor approves it. 
3. Avoid alcohol, tobacco and excess in eating. 
4. Keep your bowels in good condition. 
5. Be sure that your teeth are healthy. 
6. Have a thorough physical examination once a year. 
7. Avoid emotional upsets as much as possible. 
8. Return for re-examination when requested. 
21 Retrobulbar Neuritis. This is an inflammation of that portion of the 
optic nerve which is situated behind the eyeball. The inflammation 
may be so severe that on looking into the eye with the ophthalmo- 
scope, papilledema (swelling of the optic nerve head) is observed. In 
other cases diagnosis is difficult because the inflammation of the nerve, 
back of the eyeball, may be so mild that no change can be detected 
in the appearance of the head of the optic nerve, which is the only 
portion of the nerve accessible to visual examination. Patients who 
have retrobulbar neuritis commonly complain of poor vision one day 
and better vision the next, or they may have attacks of blurred vision 
lasting only a few moments. Retrobulbar neuritis is common in young 
people between 10 and 20 years of age. 
Cataract. The lens is the magnifying glass of the eyeball. Normally, 
it is perfectly transparent. If it loses this transparency and becomes 
opaque, a cataract is present. 
Recently it has been found that German measles occurring in the 
first three months of pregnancy has resulted in congenital cataract 
and other congenital abnormalities in the offspring. 
A cataract may be present at birth, in which case it is known as a 
congenital cataract. It may take on various appearances, one of them 
being a lamellar cataract as shown in figure 11 A. It is represented by 
a white opacity in the center of the pupil. This type of cataract, of 
course, is fully developed when it comes to the attention of the oculist. 
Since congenital cataract shows hereditary tendencies, it is unwise for 
such an individual to marry into a family where this condition has 
occurred. There are 5,408 pupils in the United States residential and 
day schools for the blind. Of this number 14.2 per cent are blind as 
a result of congenital cataract. 
Another type of cataract is the incipient senile cataract (Fig, 1 IB) 
the type that develops in people past middle age. It is probable that 
age alone is not the most important factor in the production of the 
cataract. 
We are beginning to realize that the patient’s general condition 
plays an important part in the causation of cataract. Several years ago 
in a certain hospital in this city, every patient with a cataract was im- 
mediately operated upon. At present in most hospitals careful general 
studies, including Wassermann tests, urinalysis and blood chemistry 
are usually made before operation is advised. 
For a long time we have been impressed with the close relation 
that exists between chronic infection and cataract. We are beinsj 
forced to the conclusion that cataract has a cause, even if we are un- Fig. 11A —Lamellar cataract (congenital). 1 — iris; 2 — central cloudy (catarac 
tons) portion of lens. 
Fig. 11B — Incipient senile cataract. 1 — iris; 2 — spoke-like opacities in the outer 
layers of the lens. 
able to find the cause. In the present state of our knowledge, we must 
make every effort to find that cause, whether it be in the nose, 
throat, sinuses, teeth, intestinal tract, blood or glandular system. 
Finally a brief word on the treatment of cataract. Once the cataract 
has become established, it cannot be dissolved; it consists of degener- 
ated lens fibers enclosed by the lens capsule. In the incipient stage we 
may see improvement under appropriate general treatment, but once 
the fibers are degenerated they will never return to normal. 
Pathologic or Disease Changes in the Fundus 
(Or Interior of the Eyeball) 
The normal background (fundus) of the eye is shown in figure 12. 
From the center of the papilla or optic disk (the spot where the nerve 
enters the eyeball) the veins and arteries branch out over the entire 
fundus of the eye. The normally pigmented fundus has an.orange- 
brown-red appearance. In the exact center is the macula lutea or 
yellow spot and in the center of this is the fovea centralis, the point 
of most acute vision. 
Progressive Myopia (Near-sightedness). This refractive error may 
become so severe that it results in damage to the retina and choroid 
23 Fig. 12 —The normal background of the eye. A —optic disk; B —branch of 
vein; C — artery; D — macula lutea or yellow spot; E —fovea centralis. 
through excessive stretching of the eyeball (see Fig. 13). Such cases 
of malignant myopia are fortunately rare and are encountered less 
frequently now that we are taking better care of the health of our 
children. 
The usual type of myopia, while it is progressive, should not be 
regarded as a disease. Its progression is associated with the growth of 
the child and stops when the body ceases to grow. 
Retinal Arteriosclerosis. One of the most important phases of the 
entire field of medicine is included under the heading of cardiovas- 
cular-renal disease, i.e., disease of the heart, the blood vessels and the 
kidneys. These three systems are usually classified together because 
whenever one system is diseased the others tend to be involved. While 
various classifications have been attempted, their value is limited. The 
chief fact to bear in mind is that we are sometimes able to detect 
disease of the heart, kidney and blood vessels by examining the retina 
with the ophthalmoscope. 
24 Fig. 13 —Schematic representation of progressive myopia. A — normal contour 
of eye; B — stretched contour of myopia eye. 
Recently it has been shown that diet rich in cholestrol and other 
fatty substances is an important factor in producing arteriosclerosis. 
A low cholesterol and salt free diet, such as the rice diet, is an effective 
means of controlling this common systemic disorder. 
The causes of arteriosclerosis are not definitely determined. Here 
again, a general study of the patient is most important. We studied 71 
patients and of these only 14 had uncomplicated hardening of the 
arteries, while 47 were complicated by focal infection. (Ten sub- 
mitted no medical report). This illustrates the importance of a general 
physical examination and suggests the need for consideration of focal 
infection. 
Diabetic Retinopathy. Figure 14 shows the fundus of a patient suf- 
fering from diabetes. It illustrates well the hardening of the arteries, 
indentations of the veins, hemorrhages, and small whitish spots which 
are the end result of inflammation. A careful examination of the 
fundus gives important clues to the presence of certain systemic 
diseases. The exact diagnosis must of course be left for the physician 
to make. 
25 Fig. 14 —Fundus drawing of a patient with diabetic retinopathy. Note the 
grayish white deposits and atrophic areas; the advanced hardening of the 
arteries shown by the indentation of the veins by the arteries; the changes in 
the caliber of the vessels, and the narrowing of the light streak; the rounded 
deep and superficial flame-shaped hemorrhages. 
Ocular Syphilis. This is a general infectious disease which is less 
frequent now than in years past. Hard chancre (the primary lesion) of 
the eyelids is very rare. The iris may be infected by syphilis in the 
secondary and tertiary stages. 
The disease may also affect the tissue in the back of the eye. When 
it involves the seeing coat (the retina) it also invades the blood vessel 
coat (the choroid) thus resulting in chorioretinitis. In many cases 
syphilitic retinitis takes on a form which simulates retinitis pigmen- 
tosa (a progressive disease of the retina with pigmentation, the cause 
of which is unknown). 
Fortunately syphilis is one of the diseases which can be controlled 
and sometimes even cured. In addition to the arsenicals which have 
been used for the last forty years, penicillin in large doses is now 
being successfully employed. 
26 Ocular Tuberculosis. Tuberculosis of the eye forms an important 
chapter in the diseases of the eye. Tuberculosis is difficult to diagnose. 
1'he skin tests are likely to be positive in any healthy person over five 
years of age. Therefore, to make sure that the diagnosis is correct, it 
would be necessary to remove the eyeball and examine it. Yet, we 
feel that a markedly positive skin test, performed by injecting tuber- 
culin into the skin, may be indicative of tuberculosis. 
Acute miliary tuberculosis of the eye is usually seen only in the 
terminal stages of tuberculosis of the lungs, shortly before the patient 
dies. We see litlc white areas, which are tubercles, scattered through- 
out the fundus. 
Another type of this disease, commonly due to tuberculosis, is dis- 
seminated chorioretinitis, that is, scattered areas of inflammation affect- 
ing the choroid and retina. These patients, mostly children, should 
have the best possible general care, and they should not be permitted 
to strain their eyes. 
Another type of tuberculosis affects the central part of the back of 
the eye and may destroy central vision. We also see nontubcrculous 
inflammation of the back of the eye which looks more or less like 
tuberculosis, so that it is often hard to differentiate among these con- 
ditions. 
Since it is difficult to determine with certainty whether or not one 
is dealing with tuberculosis in this type of inflammation in the back 
of the eye, it is generally conceded that it is most important to rule 
out all other causes before the inflammation can be diagnosed as 
tuberculous. Similar inflammations in the back of the eye may be 
caused by dental, sinus, tonsil or gallbladder infections. 
Conclusion 
In determining the causes of eye conditions we must take every 
possible factor into consideration. We are too likely to be enthusiastic 
about one theory. One physician may believe that the majority of eye 
diseases are due to tuberculosis, another may accuse the tonsils, an- 
other the teeth, a fourth the sinuses, but none of these should be con- 
sidered to the exclusion of the others. The more we see of the practice 
of diseases of the eye the more we feel that one must make' a very 
thorough and complete general examination of eye patients, and ac- 
company local treatment of the eyes with the treatment of systemic 
conditions. Above all, one must consider the sociologic and the psycho- 
logic aspects of each individual case. 
27 GOVERNOR 
Thomas E. Dewey 
STATE BOARD OF SOCIAL WELFARE 
Henry Root Stern, Chairman 
STATE DEPARTMENT OF SOCIAL WELFARE 
Robert T, Lansdale, Commissioner 
STATE COMMISSION FOR THE BLIND 
Mrs. Blanche P. Gilman, Chairman 
Madeleine W. Smith, Vice Chairman Brooklyn 
David F. Gillette, M.D. Syracuse 
Winthrop K. Howe, Jr. Rochester 
John P. Patterson Buffalo 
Grace S. Harper, Director 
Ruth B. McCoy, Assistant Director 
Herbert R. Brown, Director 
Vocational Rehabilitation Service MEDICAL AND ADVISORY COMMITTEE 
STATE COMMISSION FOR THE BLIND 
Raymond E. Meek, m.d. 
Chairman New York 
Walter S. Atkinson, m.d. 
Watertown 
Conrad Berens, m.d New York 
Lillian DeArmit, m.d. 
State Department of Education 
Walter F. Duggan, m.d Utica 
David F. Gillette, m.d. . . Syracuse 
John F. Gipner, m.d., . Rochester 
Loren P. Guy, m.d New York 
Harry V. Judge, m.d Albany 
Ivan J. Koenig, m.d Buffalo 
Robert F. Korns, m.d. 
State Department of Health 
Ralph I. Lloyd, m.d Brooklyn 
Raymond L. Pfeiffer, m.d. 
New York 
Christopher Wood, m.d., White Plains