transient or permanent. The former variety is often put down as
rheumatic, when it is really a symptom of tabes dorsalis. The permanent
paralysis is frequently an accompaniment of the affections of the base
of the brain: when these are located in the middle fossa of the skull
it is often associated with paralysis of the facial. If hemiplegia be
present, the lesion is usually situated farther back toward the exit of
the nerve from the pons. Graux[264] and Ferréol have called attention
to a form of paresis which results from disease of the nucleus of the
sixth pair. In this form, owing to the affection of the filament which
the nucleus of the sixth nerve gives to the nucleus of the third nerve,
which is distributed to the internal rectus of the other side, the
amount of the secondary deviation is much {790} diminished, and there
is more or less the appearance of an ordinary concomitant convergent
squint (where, as is well known, the excursions of the two eyes are
nearly equal). In one case, where the autopsy showed that a small
tubercle had been developed at the junction of the medulla and pons,
just beneath the surface of the fourth ventricle, there was no other
symptom than this conjugate deviation of the eyes. In another case, in
which there was hemiplegia (hemiplégie alterne), a tubercle was found
higher up in the pons, bulging into the fourth ventricle. In addition
to the conjugate deviation of the eyes already mentioned, Graux and
Ferréol believe that this central form of paralysis is distinguished by
its gradual access, slow development, and persistence. They say that in
pure cases of lesion of the nucleus it is characterized by the absence
of all other symptoms, and still further assert that in those cases in
which it is but partially involved the accompanying symptoms are either
complete facial paralysis or alternate hemiplegia.
[Footnote 264: _Thèse de Paris_.]
Affections of the Seventh Pair.
Loss of power in the orbicularis palpebrarum, and consequent
lagophthalmos, is frequently encountered as part of paralysis of the
facial nerve. Where the paralysis is complete, it prevents closure of
the eyelids. Variation in the size of the palpebral fissure is,
however, by no means abolished, for, owing to relaxation of the levator
palpebrarum, the fissure diminishes when the patient looks down, but is
increased by the activity of this muscle when he looks up.
BLEPHAROSPASM.--Spasmodic closure of the lids is frequent in
phlyctenular conjunctivitis and in many corneal and conjunctival
affections. It is evidently reflex in its origin, and often entirely
out of proportion to the amount of conjunctival or corneal disease. A
foreign body under the lids will frequently give rise to a similar
state of reflex spasm. We also encounter a greater or less degree of
twitching of the lids as part of general or local chorea.
Affections of the Twelfth Pair.
BULBAR PARALYSIS, LABIO-GLOSSAL LARYNGEAL PARALYSIS.--Affections of the
eye and its appendages are rather exceptional in this form of disease.
In one case Galezowski describes unilateral atrophy of the optic nerve,
and Dianoux[265] bilateral atrophy in another. In the latter the
atrophy came on after partial paralysis of the lips and of the muscles
of deglutition, it being preceded by paralysis of the right external
rectus. Hallopeau[266] quotes a case from Wachsmuth where there was
partial paralysis of the facial which rendered the face immobile and
effaced its wrinkles, allowing the lower lid to fall. He cites also a
case of Hérard in which there was amblyopia and partial ptosis. He
justly remarks that such phenomena indicate an extension of the lesion
from the nucleus of the twelfth pair to other parts of the central
nervous system. {791} The pupils are sometimes described as contracted,
more rarely as dilated. Leeser quotes Leube[267] to the effect that
"paralytic myosis, when it occurs in bulbar paralysis, is generally a
sign that it is complicated either by progressive muscular atrophy or
with sclerosis of the brain and spinal cord."
[Footnote 265: Quoted by Robin, _Troubles oculaires dans les Maladies
de l'Encephale_, p. 335.]
[Footnote 266: _Des Paralysies bulbaires_, Paris, 1875, p. 41.]
[Footnote 267: _Deutsches Archiv f. klin. Med._, Bd. viii. pp. 1-19,
quoted by Leeser, p. 94.]
Mental Affections.
It is admitted by all observers that affections of the pupillary branch
of the third pair, such as mydriasis, myosis, and inequality of the
pupils, are of comparatively frequent occurrence among all classes of
the insane. There is the widest difference of opinion as to the
percentage of cases in which it occurs: thus, Nasse out of 229 cases
found 146 (64 per cent.) with difference in the size of the pupils,
while Wernicke found 24 per cent. in the Leubus Asylum, and only 13 per
cent. in the Breslau Institute. The latter author has attempted to
classify the pupillary lesions into three groups:
I. Mydriasis, with loss of accommodation, where the pupil does not
react to light nor with increased convergence of the eyes.
II. Where the pupillary difference is slight and the irides less prompt
than normal in reaction to light, all difference of the pupils
disappearing upon convergence of the eyes.
III. In which the irregularity is still less, the narrower pupil being
absolutely insensitive to light, but prompt in responding to
convergence, while the more dilated pupil acts promptly in obedience to
both light and convergence.
In the first group there is some lesion in the course of the third
pair; in the second, some lesion of the sympathetic either in the
cilio-spinal centre or in its unknown intracranial distribution; whilst
in the third, which is not so readily explained, there is possibly an
affection of those fibres which pass from the third pair to the optic
nerve. Foerster[268] states that he has frequently seen cases where at
different times the same pupil under similar circumstances showed
different diameters; also asserting that variation in the relative
sizes of the two pupils sometimes occurred within a few days or weeks.
He also maintains that in many cases the occurrence of inequality in
the pupils precedes and presages the occurrence of insanity; and as a
marked example of it he quotes the case of a friend and colleague who
observed this phenomenon in himself. This person was well aware of the
theories on the subject, and while yet of sound mind jokingly remarked
that on account of this inequality of pupils having set in, he thought
of taking up his quarters in an insane hospital. A few years later he
actually died insane in the Leubus Asylum. Myosis is said to be
frequent in states of mental exaltation. Seifert asserts that when it
is accompanied by acute mania general paralysis will sooner or later
ensue. Griesinger asserts that the same thing occurs in chronic mania.
As regards the changes in the optic discs in the insane, we find
usually recorded either a low grade of neuritis or of atrophy:
according to Leber[269] this atrophy is histologically similar to that
occurring in gray degeneration of the nerves. The outer strands are
{792} usually those most affected. Indeed, as far as these obscure
diseases are at present understood, there is no good reason why any
changes should be found in the optic nerves except the congestion which
accompanies acute or subacute mental disease and the nerve-degeneration
of various grades which might be expected to be found in all worn-out
lunatics. Illusions and hallucinations referable to the sense of sight
are not uncommon in the insane, and are perhaps due to degenerative
changes in the visual centres. In classifying such cases for study of
the intraocular changes most writers place them under the following
heads--viz.: general paralysis, dementia, mania, and melancholia,[270]
the account of the changes in the eye-ground and the proportion of
cases in which they occur being found to vary greatly.
[Footnote 268: _G. u. S._, vol. vii. p. 227.]
[Footnote 269: _A. f. O._, xiv., 2, p. 203.]
[Footnote 270: Noyes, "Ophthalmoscopic Examination of Sixty Insane
Patients in the State Asylum at Utica," pp. 6 (extra copy from _Amer.
Journ. of Insanity_, Jan., 1872).]
GENERAL PARALYSIS.--Almost all agree that in this form of the disease
we frequently have gray degeneration of the optic nerve, with pupillary
symptoms which strongly resemble those found in tabes dorsalis, in some
instances the autopsy showing the same location of spinal changes which
characterizes the changes seen in locomotor ataxia.
DEMENTIA.--In chronic dementia Albutt found either hyperæmic or
atrophic changes in the disc in 23 out of 38 cases. Noyes[271] found
hyperæmia in 18 cases, and infiltration of the optic nerve and retina
in 12. Jehn and Klein were unable to find changes in the discs of any
of the cases which they examined.
[Footnote 271: _Idem._]
MANIA.--Albutt found the discs hyperæmic except in one case examined
during a paroxysm, in which they were pale. Out of 20 cases of acute
mania, Noyes[272] found 14 which showed hyperæmia of the discs; the
discs of the remaining 6 were either anæmic or normal, these latter
cases all being of short duration (less than three months); the 6 cases
of chronic mania had eye-grounds which showed no lesion, while the
other 3 exhibited hyperæmic or inflammatory changes.
[Footnote 272: _Loc. cit._]
MELANCHOLIA.--In Noyes's examination 4 out of 5 cases had healthy
eye-ground, and 1 moderate hyperæmia and striation. Jehn found
hyperæmia in every one of 40 cases examined, 2 of these having decided
neuritis, which he supposed to be due to meningeal change.
Spinal Cord.
INJURIES TO THE SPINE.--Physiologists have frequently shown that
pupillary and other eye-symptoms may be produced by experimental injury
to the spinal cord of animals, which would lead us to naturally expect
analogous results in man in cases of spinal fracture and injury. This
subject has received great attention in England, where spinal injury
from railway accidents appears unusually frequent. Albutt[273] tells us
that it is tolerably certain that disturbance of the optic nerve and
its neighborhood is seen to follow disturbance of the spine with
sufficient frequency and uniformity to establish the probability of a
causal relation between the two events. Erichsen,[274] who has
collected his large clinical experience {793} into a book on
_Concussion of the Spine_, after citing Plutarch to show how Alexander
the Great was in danger of losing his eyesight from the blow of a heavy
stone on the back of the neck, gives 53 cases (not tabulated with this
view by the author), of which 49 were apparently undoubted cases of
spinal injuries: of these, 13 (36 per cent.) showed decided
eye-symptoms. Erichsen says: "My experience accords fully with that of
Albutt. I found that in the vast majority of cases of spinal concussion
unattended by fracture or dislocation of the vertebral column there
occurred within a few weeks distinct evidence of impairment of vision."
As enumerated by this author, these symptoms consist of difficulty of
seeing in dim light, blurring and running together of the letters, and
at times (in the early stages) slight diplopia. Later, there is
photophobia, with contraction of the brow, which gives a peculiar
frown, and at times an injection of the conjunctiva; these symptoms
often being accompanied by muscæ volitantes and photopsia. He agrees
with Albutt in attributing these to an ascending meningitis, while
Wharton Jones considers that the eye symptoms are better accounted for
by the action of the cilio-spinal centre and the sympathetic filaments
springing from the dorsal and cervical cord. Wharton Jones[275] lays
stress upon the undue retention of after-images and upon the small
amount of comfort which a positive (convex) glass gives the patients,
and "to the pain extending from the bottom of the orbit to the occiput,
which is always a symptom belonging to deep-seated disturbance in the
circulation of the optic apparatus." Rondeau[276] gives an interesting
example of severe affection of the eyesight from apparently slight
injury to the spine. The patient, seventeen years old, fell on the
staircase, striking the neck and shoulders. There was complete loss of
sight. Light-perception returned in a month, and four years after he
could distinguish large objects in front of him, but vision remained
stationary at that point. Albutt informs us that the percentage of
visual affections is greater in proportion to the height of the seat of
the injury in the spine.
[Footnote 273: _Use of the Ophthalmoscope_, London, 1871.]
[Footnote 274: _Concussion of the Spine_, by John Eric Erichsen,
London, 1875.]
[Footnote 275: _Failure of Sight after Railway and Other Injuries of
the Spine and Head_, London, 1869.]
[Footnote 276: _Affections oculaires Reflexes_, Paris, 1866.]
TABES DORSALIS.--That affections of the eye are common in this grave
malady is admitted by all writers, but as to their frequency and nature
at the different stages of the disease, there is wide diversity of
opinion: this is probably in part due to the fact that from the chronic
nature of the disease, which extends usually over a period of several
years, it is rare that the case remains from beginning to end under
care of the same observer. The symptoms are of three varieties--viz.
firstly, transient paralyses of the external muscles of the eye;
secondly, changes in the iris and ciliary body; and, thirdly,
affections of the optic nerve. The first-named symptoms are frequent in
the early stages of the disease. Sometimes they affect the external
muscles supplied by the third pair, and at others the rectus externus.
Their transient character and frequency, while admitted by all
observers, have as yet received no adequate explanation, it being
indeed difficult to see why transient affections of the motor nerves
should be so common in a disease which has its seat in the posterior
sensory columns of the spinal cord, and which presents such formidable
and irreparable lesions. The pupillary symptoms are, as a rule, those
of myosis, sometimes mydriasis, and at times the so-called
Argyll-Robertson {794} symptom (viz. a moderate myosis, with diminished
reaction to light, but prompt response to convergence and
accommodation). The last symptom is by no means present in all cases
and at all stages of the complaint; but where it exists there is a
remarkable resistance to the action of mydriatics. Trousseau was
probably the first to call attention to this state of affairs. The
writer has repeatedly seen cases where a strong solution of sulphate of
atropia failed to produce any more than one-third of the usual
dilatation produced by the same amount of the drug. Trousseau and
Duchenne have both observed that during attacks of violent pain the
pupils of ataxic patients will sometimes undergo temporary dilatation.
Atrophy of the optic nerve (either partial or complete) is a frequent,
and often an early, symptom of tabes dorsalis, and even may precede by
many years the development of spinal symptoms. Foerster relates a case
where complete optic atrophy preceded the development of all other
symptoms by a period of three years, he having seen a number of other
instances when atrophy preceded the other symptoms for a less period.
Charcot records a case where the interval was ten years, and states
that sooner or later locomotor ataxia develops in the majority of cases
of optic atrophy in his wards in the Salpêtrière. Gowers gives two
interesting cases, in one of which blindness came on fifteen years
before the development of the other symptoms, the interval in the
second being twenty years. Buzzard[277] also has recorded an
observation where blindness and lightning pains manifested themselves
fifteen years before the development of the other ataxic symptoms. If
we were to estimate the frequency of optic atrophy as a symptom of
early development of tabes dorsalis by the cases seen at ophthalmic
hospitals, we should probably much overrate its proportion, inasmuch as
those cases in which atrophy is a more marked and early symptom alone
resort to such places. Leber found that 13 (26 per cent.) out of 87
cases at his clinic had spinal symptoms, while Gowers gives 20 per
cent. as a relation existing between degeneration of the optic nerves
and tabes. The latter author thinks that the ratio should really be
stated as 15 per cent., because 5 per cent. was due to cases which had
been sent to him for examination by his colleagues. Nettleship
classifies 76 cases of optic atrophy as follows: 38 as presenting
undoubted symptoms of locomotor ataxia; 11 as showing mixed spinal and
cerebral symptoms (as in general paralysis of the insane); 9 with other
forms of spinal degeneration without brain lesions, these associated
with reflex iridoplegia without other symptoms of spinal or cerebral
disease; and 15 only in which there was no manifest disorder of other
parts of the nervous system. In the earlier stages of degeneration of
the optic nerve in tabes dorsalis the discs are usually of a dull
reddish-gray tint, and, while they are still capillary superficially,
their deeper layers next to the lamina cribrosa have a decidedly
diminished blood-circulation, and appear of a marked and more neutral
gray color. The surface of the discs often looks more or less fluffy,
there being enough haze of the retinal fibres to veil, and at times to
hide, the scleral ring. Later, the superficial capillarity disappears
and the discs assume a pallid, filled-in aspect, being surrounded by a
scleral ring which is everywhere too broad: at this stage the main
stems of the retinal arteries and veins exhibit no marked change in
calibre, but later on we find them {795} shrinking, and the surface of
the disc becomes excavated, the nerve itself often assuming a greenish
tint. The earlier stages of such degenerations often exist for a long
time, and are demonstrable by the ophthalmoscope before the sight is
sufficiently impaired to prevent the patient from executing any
ordinary work; this being dependent upon the facts that at first there
is only a concentric diminution of the field for form and colors, while
central vision remains for a long time unaffected. According to
Foerster, this contraction of the field commences at the outer part. In
advanced cases there are often irregular sector-like defects. This
state of affairs makes it probable that while the number of cases in
which total blindness precedes the development of tabetic symptoms is
probably rated much too high, from the natural gathering of such cases
at ophthalmic hospitals, yet, nevertheless, the frequency of incomplete
gray degeneration of the optic nerves in the early stages of the
complaint is probably, as a rule, much underrated.
[Footnote 277: _Brain_, ii. 1878, p. 168.]
Foerster has most justly called attention to the remarkable mental
cheerfulness of persons laboring under this malady, and states that he
has frequently seen cases where the patients would insist that they
were improving, while examination of the acuity and of the field of
vision showed steady failure of the eyesight. The writer's personal
experience has on several occasions substantiated this statement.
According to Cyon,[278] tabes presents three varieties: First, tabes
dorsalis. This variety commences with paralyses of the eye-muscles and
amblyopia. The pupils are not contracted. The amblyopia progresses.
Cramp-like disturbances of innervation are always present, with a want
of co-ordination of movements and anæsthesia of the upper extremities,
while mental disturbances are often demonstrable. Second, tabes
cervicalis. Myosis, with intense boring pains in the extremities and
impotence, are its chief characteristics. Ataxia is rare, and
disturbances of vision develop only late in the course of the disease.
Third, a class which he considers the true form of tabes dorsalis, in
which there are marked anæsthesia, formication, bladder and rectal
symptoms, associated with motor disturbances which often end in
paralysis. In such cases there are no eye symptoms except occasional
dilatation of the pupil. The same writer has collected 203 cases
reported by various authors, and gives the following tables as showing
the relative frequency of eye symptoms:
Amblyopia . . . . . . . . . . . . . . . . . . . . . . . . 33 times.
Paralysis of eye-muscles . . . . . . . . . . . . . . . . 30 "
Mydriasis . . . . . . . . . . . . . . . . . . . . . . . . 3 "
Myosis . . . . . . . . . . . . . . . . . . . . . . . . . 9 "
--
75
Amaurosis with affections of eye-muscles . . . . . . . . 16 times.
Amaurosis with mydriasis . . . . . . . . . . . . . . . . 8 "
" " myosis . . . . . . . . . . . . . . . . . . 1 "
Affections of the eye-muscles with mydriasis . . . . . . 4 "
Amaurosis with mydriasis and affection of the eye-muscles 2 "
He remarks[279] that the number of reported cases of mydriasis is
probably excessive, and says that dilatation has been improperly noted,
as, for instance, where one pupil is normal and the other contracted.
As regards the frequency of the Argyll-Robertson symptoms, Vincent[280]
found it {796} present in 40 cases out of 51, in which there were 7
cases of amaurosis with immobile pupils, 5 being marked exceptions to
the rule. Out of 51 cases of tabes, the same author found myosis in 27.
The statements of Vincent (as will be seen) differ materially from
those of Cyon. Erb[281] found that in 56 cases, there were only 7 in
which the optic nerves were affected (12½ per cent.), while in 17 there
were affections of the eye-muscles (30-3/10 per cent.). He considers
myosis a frequent symptom, but thinks that the stage at which it
develops is not yet determined. The anatomical cause of the want of
sensitiveness of the pupils to light, while they retain their movements
of convergence and accommodation, has not been well made out.
Vincent[282] attributes it to a paralysis of the excito-motor filaments
which supply the iris, and which he locates at the upper portion of the
spine; while Wernicke thinks it due to degeneration of the filaments
which go from the third pair to the optic nerve. Hughlings-Jackson[283]
tells us that the pupils which fail to react to light often act but
slightly with convergence, and in a note gives two cases of absolutely
immobile pupils where the accommodation was nearly normal for the age.
In fact, much remains to be accomplished in the study of the
innervation of the iris and ciliary muscle in tabes. The proportion of
cases in which cycloplegia occurs, and what relation it bears in point
of time and frequency to the presence of iridoplegia, are far from
being well made out. Jackson also insists that tabes does not
necessarily follow in all cases of long-standing optic atrophy. On a
basis of 72 cases Gowers says that some formal ophthalmoplegia interna
was present in 92 per cent. He groups these cases into three stages:
No. 1, where there is loss of knee-jerks, lightning pains, difficulty
of standing with toes out and heels together, there being a want of
ataxic gait; 2, where there is an ataxic gait, but the patient can
still walk by the aid of a stick; 3, where the patient cannot walk
without the assistance of another person. In 23 of his cases in the
first stage (84 per cent.) symptoms of palsy of some of the intraocular
muscles were found; in the second stage, 29 cases (93 per cent.); in
the third stage, 18 cases (100 per cent.). Erb has called attention to
the fact that reflex dilatation of the pupil from sharp stimulation of
the skin of the temple is usually absent where we have the
Argyll-Robertson pupil. Gowers admits that this is the rule, but has
seen several cases where, although there was no attempt at myosis on
exposure to light, yet there was marked dilatation on stimulating the
skin.
[Footnote 278: _Tabes Dorsalis_ Berlin, 1866, p. 43.]
[Footnote 279: _Loc. cit._, p. 71.]
[Footnote 280: _Thèse de Paris_, cited by Robin, p. 20.]
[Footnote 281: _Nagel's Jahresbericht der Ophthalmologie_, 1872, p.
150.]
[Footnote 282: _Thèse de Paris_.]
[Footnote 283: _Transactions of the Ophthalmological Society of the
United Kingdom_, vol. i. pp. 139-154.]
Unclassified Nerve Diseases.
DIABETES.[283]
[Footnote 283: This affection has been placed here for convenience of
classification, and because there is a form of the disease which is of
neurotic origin.]