OPERATIONS ON EYE.
_Operations on the Eye and its Appendages._
OPERATIONS ON THE LIDS.--
[Illustration: FIG. VII.[81]]
[Illustration: FIG. VIII.[82]]
1. FOR ENTROPIUM OR INVERSION OF THE LIDS, OFTEN COMBINED WITH
TRICHIASIS, IRREGULARITY OF THE CILIÆ.--As in many cases the entropium
seems to depend partly on a too great laxity of the skin of the lid,
combined occasionally with spasm of the orbicularis, the simplest and
most natural plan of operation is (_a_) to remove (Fig. VII. _a_) an
elliptical portion of skin, extending transversely along the whole
length of the affected lid, including the fibres of the orbicularis
lying below it, and then to unite the edges with several points of fine
suture. (_b_) An improvement on this in obstinate cases is proposed by
Mr. Streatfeild (Fig. VIII.) He continues the same incision, but in
addition removes a long narrow wedge-shaped portion of the tarsal
cartilage, grooving it without entirely cutting it through, in such a
manner that the retraction of the skin bends the cartilage backwards,
thus everting to a very considerable extent the previously inverted
ciliæ.[83]
2. ECTROPIUM is the opposite condition from entropium; in it the eyelids
are everted and the palpebral conjunctiva is exposed.
If the result of cicatrix, of a burn, or of disease of bone, the
treatment must be varied according to circumstances, and in many cases,
skin must be transplanted to fill the gap.
In the more usual cases resulting from chronic inflammation the
following simple operations are required:--1. In mild cases the excision
of an elliptical portion of conjunctiva may suffice, the edges must not
be left to contract, but should be brought carefully together. 2. In
more chronic cases, where all the tissues of the lid are very lax, it is
necessary to remove (Fig. VII. _b_) a V-shaped portion of lid and skin,
and then stitch it very carefully up with interrupted sutures.
TUMOURS OF EYELIDS.--1. _Encysted tumours; cysts of the lids; tarsal
tumour._--Under these and similar names are recognised a very frequent
form of disease, chiefly in the upper lid: small tumours which rarely
exceed half a pea in size, convex towards the skin, which is freely
moveable over them; they give no pain, and are annoying only from their
bulk and deformity.
_Operation._--Evert the lid, incise the conjunctiva freely over the
tumour, insert the blunt end of a probe and roughly stir up the contents
of the cyst, thus evacuating it. If the tumour is large and of old
standing it may be requisite to cut out an elliptical or circular
portion of its conjunctival wall. The probe may require to be reapplied
once or twice at intervals of two or three days, and in certain rare
cases it may be necessary as a last resource freely to cauterise the
inside of the cyst with the solid nitrate of silver.
In _no_ case is it ever necessary to excise the tumour from the outside
of the eyelid; when this has been done in error there frequently remains
an awkward and unsightly scar.
2. _Fibrous cysts_, frequently congenital, are met with in one
situation, just over the external angular process of the frontal bone.
These are larger in size than the preceding, ranging from the size of a
barley pickle to that of an almond. Their treatment is excision by a
prolonged and careful dissection from the periosteum, to which they
almost invariably are adherent.
OPERATIONS ON THE LACHRYMAL ORGANS.--In a system of ophthalmic surgery,
various operative procedures might be detailed under this head,
authorised and sanctioned by old custom. Excision of a diseased
lachrymal gland, and removal of stones in the gland or ducts, need no
special directions for their performance, and the operation immediately
to be described, under the head of Mr. Bowman's operation, is applicable
in almost every one of the diseased conditions of the lachrymal canal,
sac, and nasal duct, to the exclusion of all the older methods.
_Mr. Bowman's Operation._--In cases of obstruction of the punctum,
canaliculus, and nasal duct, resulting in watery eye, accumulation of
mucus in the canal, and dryness of the nose, great difficulty used to be
experienced in the treatment. To pass a probe along the punctum was
extremely difficult, in fact, possible only with a very small one, while
the common operation of opening the dilated sac, through the skin, and
then passing probes through this artificial opening, was found quite
useless from the rapid closure of the wound, unless the treatment was
followed up by the insertion and retention of a style in the nasal
duct. This was painful, unsightly, often unsuccessful; and even in some
cases dangerous, from the amount of irritation, suppuration, and even
caries of the nasal bones which is set up.
The principle of Mr. Bowman's most excellent operation is, that the
punctum, canaliculus, and nasal duct resemble in many respects the
urethral passage, and in cases of stricture require to be treated on the
same principle. If, then, it were possible to pass instruments gradually
increasing in size through the seat of stricture, it would be gradually
dilated. It is, however, in the normal state of parts, impossible to
pass any instrument beyond the size of a human hair past the curve which
the canaliculus makes on its entrance to the duct, hence the proper
dilatation cannot be performed. Again, it is found that the puncta,
specially the lower one, are themselves very often to blame, in cases of
watery eye, sometimes because they are inverted or everted, more often
because, sympathising with the lid, they are turgid, angry, and
inflamed, pouting and closed like the orifice of the urethra in a
gonorrhoea.
Mr. Bowman found that by slitting up the inferior punctum and
canaliculus as far as the caruncula, several advantages were
gained:--(1.) The swollen, angry, displaced punctum no longer impeded
the entrance of the tears; (2.) and chiefly when the canaliculus was
slit up, the curve, or rather angle, which impeded the passage of
probes, was done away with, and the nasal duct could be readily and
thoroughly dilated.
_Operation._--The surgeon stands behind the patient, who is seated, and
leans his head on the surgeon's chest. The affected lid is then drawn
gently downwards on the cheek, so as to evert and thoroughly expose the
lower punctum. Into this the surgeon introduces a fine probe of steel
gilt, the first inch of which is very thin, especially at the point, and
deeply grooved on one side, exactly like a small (and straight) Syme's
stricture director.
Keeping the canal relaxed by relaxing his hold on the lid, the surgeon
now gently wriggles the probe along the canaliculus, gradually
stretching it as the probe advances, so as to avoid catching of the
sides of the canal before the point of the instrument, till he is
satisfied that it has fairly entered the nasal duct. He then stretches
the eyelid, brings the handle of the probe out over the cheek so as to
evert the punctum as much as possible, and then with a fine
sharp-pointed knife enters the groove (Fig. IX.), and fairly slits up
the punctum and the canal to the full extent. The incision should be as
straight as possible, and through the upper wall of the canaliculus. A
dexterous turn of the instrument upwards on the forehead will generally
enable it to be passed at once fairly into the nose through the nasal
duct, the usual rule being observed of passing it downwards and slightly
backwards, the handle of the probe passing just over the supraorbital
notch.
[Illustration: FIG. IX.[84]]
For several days after the operation the probe will have to be passed,
both to prevent the wound in the canaliculus from healing up, which it
is too apt to do, and also to gradually dilate the nasal duct if it has
been previously strictured. Probes and directors of various sizes are
required; in fact very much the same instruments (in miniature) as are
required for the treatment of stricture of the urethra.
Mr. Greenslade has invented a very ingenious little instrument, of
which, through his kindness, I am able to show a woodcut (Fig. X.), for
slitting up the canaliculus without having to fit the knife in the
groove.
[Illustration: FIG. X.]
PTERYGIUM, the reddish fleshy triangular growth, with its base at the
inner canthus, and its apex spreading to and often over the cornea,
requires invariably a small operation for its removal. In most cases it
will be found sufficient merely to raise the lax portion over the
sclerotic with forceps, and divide it freely, removing a transverse
portion. If it has encroached upon the cornea, the portion interfering
with vision must be dissected off with great care and removed.
In some cases, however, it has been found that after removal of a large
pterygium, a retraction of the caruncle and the semilunar fold is apt to
take place, which renders the eyeball unpleasantly prominent. To avoid
this the pterygium may be carefully dissected up from its apex to near
its base, and then displaced laterally either upwards or downwards, its
apex and sides being stitched to a previously prepared site of
conjunctiva.
OPERATION FOR CONVERGENT STRABISMUS.--_Division of the internal
rectus._--_Subconjunctival operation._--The spring-wire speculum (C)
separating the lids, the surgeon divides the conjunctiva by a pair of
scissors in a horizontal line (Fig. XI. A A) from the inner margin of
the cornea, a little below its transverse diameter to the caruncle,
then snipping through the sub-conjunctival tissue, he passes a blunt
hook bent at an obtuse angle under the tendon of the internal rectus,
and endeavours by depressing the handle to project the point of the hook
at the wound. Then with successive snips of the scissors he divides the
tendon on the hook, close to its sclerotic margin. Lest it should not be
freely divided, various dips with the hook may be made to catch any
stray fibres left untouched; but very great care should be taken not to
wound the conjunctiva beyond the first horizontal cut in it. The tendon
being divided satisfactorily, the edges of conjunctiva should be
replaced, and the eye closed for a few hours.
[Illustration: FIG. XI.[85]]
The original operation of Dieffenbach, now rarely practised, consisted
in making an incision, B B, across the tendon, then, by cutting the
areolar tissue exposing the insertion of the tendon, and dividing it
freely; after which the sclerotic in the neighbourhood was to be cleaned
and any band of fibres divided. There are risks on the one hand of a
most unseemly exophthalmos with divergent squint, and on the other of a
retraction of the semilunar fold, so that the sub-conjunctival operation
is always preferable.
OPERATIONS FOR DIVERGENT SQUINT.--This very serious deformity is often
the result of the operation for convergent squint, and is associated
with a fixed, leering, and prominent eye, and frequently with most
annoying double vision.
1. In a simple case of primary divergent strabismus (very rare) it is
sufficient simply to divide the external rectus in the manner already
described for division of the internal.
2. If secondary to an operation for convergent squint, the indication is
to restore the cut internal rectus to a position on the sclerotic a
little behind its previous one, as the cause of the divergence is found
in a complete detachment of the internal rectus. This is attempted in
various ways.
(1.) _Jules Guérin_ carefully divided the conjunctiva over it, and
sought for the remains of the internal rectus, freeing it from its
attachments. He then passed a thread through the sclerotic on the
_outer_ side of the globe, and by pulling on it and fixing it across the
nose, rotated the eye inwards, in the hope that the remains of the
internal rectus would secure a new attachment.
(2.) _Graefe's modification_ of this is more certain. Without any minute
dissection he merely separated the internal rectus, along with the
conjunctiva, and fascia over it, so that it can be pulled forwards, then
cut the external rectus, and inverted the eyeball to a sufficient extent
by means of a thread passed through the portion of the tendon of the
external rectus, which remains attached to the sclerotic. The risk of
all these operations, in which both muscles are divided, is protrusion
of the eyeball from the removal of muscular tension.
(3.) _Solomon's operation for the radical cure of extreme divergent
strabismus_,[86] is at first sight a very curious one. Without going
into all the details, the steps are as follows:--
_a._ A square-shaped flap, with its attached base at the nasal side, is
raised, containing the remains of the inner rectus and its adjacent
parts.
_b._ A flap similar in shape and size, but different in the position of
its attached base, is made on the other side of the cornea. It is made
by dividing the external rectus just behind its tendon, and then
reflecting forwards the tendon with its conjunctiva.
_c._ These two flaps are united over the vertical meridian of the cornea
by sutures, three generally being sufficient. This entirely hides the
cornea for a time, but eventually shrivels and contracts, and the
remnants are to be cut off with scissors three weeks after the
operation.
PUNCTURE OF THE CORNEA.--_Paracentesis of the Anterior
Chamber._--_Tapping of the Aqueous Humour._--This very simple operation
is in many cases extremely useful. In cases of corneal ulcer, the result
either of injury or disease, where there is much pain in the bone, and
evidence of tension of the globe, it gives great relief, and when
repeated at short intervals greatly hastens a cure. Sperino of Turin
recommends its frequent use in cases of chronic glaucoma.
_Operation._--The surgeon stands behind the patient, who is seated; the
lids being fixed, the upper by the surgeon's left hand, and the lower by
an assistant, the cornea is punctured a little in front of the sclerotic
margin, either with a broad needle, or, what is as good, a well-worn
Beer's knife. Care must be taken on entering the knife, on the one hand,
not to wound the iris, which is sometimes arched forwards in the cases
of commencing glaucoma, and, on the other, fairly to enter the anterior
chamber, not merely split up the layers of the cornea. On withdrawing
the cataract knife, the aqueous humour gets out by its side, aided by a
slight turn of the knife, sometimes with great force, and in much larger
quantity than usual. If the operation has been done by a needle, a blunt
probe requires to be introduced on the removal of the needle. Once
punctured, the remarkable fact is that the same wound suffices for many
succeeding tappings, which are effected by pressing the probe into the
wound day after day, sometimes several times a day, with great relief
to the symptoms. If the probe is to be used for succeeding evacuations,
the operator must be careful to remember the exact spot at which the
needle or knife was entered. To facilitate remembering it, it is best,
when nothing prevents it, to operate always in the same spot. Sperino
chooses the horizontal meridian of the cornea at the temporal side, at
the junction of the cornea and sclerotic.
CATARACT OPERATIONS.--Here we cannot enter into any discussion of the
pathology of cataract and the varieties of it. Enough for our purpose to
know that the lens is in some cases hard, in others soft, and that thus
in the latter it may be removed piecemeal, and by a small incision,
while in the former, removal must be almost entire, and by a larger
opening.
In cataract, the lens, which should be transparent, has become opaque,
and the object of treatment is to get it out of the line of sight, to
prevent it from obstructing, now that it can no longer assist sight.
The operations used for this end may be classed under three heads:--
1. _Operations for the removal of the lens out of the way without its
removal from the eye._--These used to be extensively practised under the
name couching, and are of two kinds,--_Depression_, where the lens is
simply pushed down from its place by a needle; _Reclination_, in which
it is shoved backwards (turning on its transverse axis) as well as
downwards. These are relics of old surgery, and very rarely practised by
any oculists of eminence, as, though easy to perform, and with very
flattering immediate results, the risks of chronic inflammation of the
whole globe and injury to the retina are very great.
2. _For solution._--THE NEEDLE OPERATION.--Suitable (among other cases)
especially in congenital cataracts in infants, and in cases of diabetic
cataract.
The principle of this operation is that the lens, once the capsule is
freely opened in front and the aqueous humour admitted, is found rapidly
to become absorbed and disappear, if the cataract has been a soft one.
_Operation._--A needle with a lance-shaped head is to be used. It should
be so made that the rounded shaft of the needle is just large enough to
play freely in the wound made by the broader point, and yet not so small
as to allow the aqueous humour to escape rapidly. The pupil has been
dilated, the patient is lying on his back, and the globe is fixed by
forceps attached to the conjunctiva of the inner side of the eye, and
held by an assistant. The surgeon then enters the needle close to the
sclerotic margin of the cornea, carries it fairly on in the anterior
chamber, till the centre of the pupil is reached. He then, by bringing
forward the handle, projects the point backwards against the anterior
capsule, which he freely lacerates with the point and edge in several
directions.
In infants, where processes of repair go on very rapidly, the whole lens
may be freely broken up. In diabetic cataract, or indeed in all cases of
solution, where the patient is adolescent or adult, or the eye at all
weak, only a small portion of the lens should be attacked at one
sitting.
The needle should then be withdrawn gradually and with great care, that
the broad axis of the blade be in exactly the same position in which it
entered, _i.e._ flat and parallel with the iris, lest the iris be
wounded, entangled, or prolapsed.
The eye is then to be closed for twenty-four hours; if there is much
pain, atropia must be freely used.
_Varieties in the Operation._--Some use two needles at once for breaking
up the lens. Some surgeons prefer to enter the needle through the
sclerotic; this complicates the operation and renders it less certain,
as the point of the needle is of course out of sight in its progress
between the iris and the lens.
Even in children this operation requires in most cases to be repeated at
least once, while in adults it may be required at short intervals for
many months.
3. _By Extraction._--In these operations the lens is at once removed
from the eye--
(1.) By linear, or perhaps, more correctly, rectilinear incision. This
method is specially suited for cases of soft cataract.
_Operation._--A fine spear-shaped needle is very cautiously introduced
through the cornea, about a line from its outer margin, and the anterior
capsule lacerated, and the lens broken up, great care being taken not to
injure the posterior capsule. The pupil must then be kept freely
dilated, the wound heals at once, and the aqueous humour reaccumulates.
[Illustration: FIG. XII.]
[Illustration: FIG. XIII.]
From three to six days after this first operation, a linear incision
(Fig. XII.) is made in the outer side of the cornea by a straight stab
from a double-edged knife, or rather spear. The size of the incision
must vary with the size and consistence of the lens, and can be
regulated by the breadth of the knife and the distance to which it is
entered. By careful withdrawal of the knife, in many cases a large
portion of the soft lens can be removed along with it, and then what
remains must be cautiously lifted out by a flat spoon introduced through
the wound, and behind the remains of the lens.
Care must be taken lest any of the lens substance remain in the wound;
with this precaution the incision generally heals rapidly, and with much
less risk of general inflammation of the ball than in the ordinary flap
operation of extraction.
EXTRACTION OF SOFT CATARACT BY SUCTION.--Mr. T. P. Teale, of
Leeds,[87] has invented an instrument by which the removal of soft
cataract is made more easy, through a linear incision by suction,
applied through the medium of a hollow curette furnished with an
india-rubber tube and mouth-piece.
The curette is of the usual size, but is roofed in (instead of
being merely grooved) to within one line of its extremity, thus
forming a tube flattened above, but terminating in a small cup.
This is screwed into an ordinary straight handle, which is hollow
for a short distance, far enough to join with a second tube fixed
at right angles to the handle, and into which the india-rubber pipe
and mouth-piece, through which suction is to be made, is attached.
In many cases it seems to serve its purpose extremely well.
Certain points require attention:--1. That the puncture to admit
the curette is large enough; 2. That its end be sufficiently
rounded; 3. Its open end must be held in the area of the pupil, and
not allowed to pass behind the iris, else there is great risk of
the iris being drawn in. Among other advantages claimed by its
inventor, the chief seems to be a more thorough removal of the lens
than by the ordinary means, and consequently less risk of opaque
deposit in the posterior capsule.
(2.) EXTRACTION BY FLAP.--When properly performed in a suitable subject,
and when free from accident, this operation is one of the most
thoroughly beautiful and satisfactory in the whole domain of surgery;
but it is difficult, and liable to many risks which neither skill nor
caution can completely guard against.
It is required in many cases of hard cataract, which are amenable
neither to solution nor linear extraction.
_Operation_ must be considered in various stages:--
_a._ To make a flap of cornea large enough to permit of the removal of
the entire lens without pressure or bruising. To make it of cornea only,
to prevent the escape of the vitreous, and to avoid injury of the iris.
The great difficulty in making the required section of the cornea is,
that we are debarred from using scissors or any ordinary knife or
scalpel in making it, for this reason, that the sawing movements
required in all ordinary cutting are inadmissible here, as any
withdrawal of the blade, however slight, would permit evacuation of the
aqueous humour, and at once be followed by prolapse of the iris before
the knife. Hence we are compelled to make the requisite flap by one
steady push of a knife, which, too, must be of such a shape as in its
entrance constantly to fill up the wound it makes. Very various shapes
and sizes of knives have been proposed, the one called Beer's knife
being the sort of model or common parent from which all the others are
derived. It is triangular in shape, with a straight back, about 12-10ths
of an inch in length, and 4-10ths broad at the base of the blade,
tapering at a straight edge from its base to its point, and also
diminishing in thickness to the point.
Considerable difference of opinion exists as to the relative merits of
an upper or lower section of the cornea. The general view at present
seems to be that an upper section is to be preferred; but in cases where
the surgeon is not ambidexterous, it is better that he should make the
section which lies easiest to his hand than attempt an upper section in
a less favourable position.
The patient should be placed flat on his back, the lids should be gently
opened, the upper one by the surgeon, the lower one by his assistant,
who is to press the lid downwards against the malar bone without
exercising any pressure on the ball. The eye should be still further
steadied by the conjunctiva and subjacent cellular tissue on the inner
side being seized by a pair of catch-forceps, still with no downward
pressure on the ball. The point of the knife must then be introduced
about a line from the outer sclerotic margin of the transverse diameter
of the cornea (Fig. XIII.), the blade being held parallel with the
fibres of the iris, pushed steadily across the anterior chamber, and
protruded as nearly as possible at the corresponding spot at the inner
side of the cornea. The aqueous humour should not escape till the
section is completed. If it does, the iris is almost certainly projected
forwards and entangled in the blade of the knife, a most annoying
accident, and one which is not easily remedied. The books tell us of
various manoeuvres by pressure or otherwise, by which the iris may be
pushed back. Practically, however, if it has once occurred it is not
easily saved from being cut. If a small portion only is involved, it is
not of much consequence; if a large portion be in danger, it is
sometimes necessary to withdraw the knife before the section is
completed, and finish it with a probe-pointed, curved bistoury.
If, however, the flap is safely finished, the lids should be gently
allowed to close for a few seconds.
On opening them again the surgeon must decide whether the corneal flap
is sufficiently large to allow the lens to come out without force; if
not, he must enlarge it either by the narrow probe-pointed "secondary
knife" or by a pair of sharp scissors. Occasionally the lens, and even a
little vitreous humour, may escape at once on the section being
completed, but this is not to be desired.
_b._ _Laceration of the Capsule of the Lens._--This is performed by
insinuating a sharp curved needle under the corneal flap, avoiding the
iris, and then tearing up the anterior capsule through the dilated
pupil, the chief point to be attended to being that the capsule be
lacerated in its entire length.
_c._ _Removal of the Lens._--This must be done with the most extreme
caution and gentleness, lest the vitreous humour be also evacuated. The
surgeon's object is to tilt the lens so as to turn it slightly on its
transverse axis, and cause the edge nearest the section to rise out of
the capsule and appear at the wound. This is best done by gentle
pressure at the required spot by the back of the needle, or by a common
probe. When the lens begins to protrude the pressure must be very,
gentle, lest it be forced out suddenly and the vitreous follow it.
Soft portions of the lens are apt to remain adherent to the wound in the
cornea. These must be removed by scoop or probe.
_Varieties in the method of Flap Extraction._--Jacobsen of Königsberg in
every case gives chloroform. He always makes his flap in the boundary
line of the cornea and the sclerotic, through a vascular structure, and
he believes that union is on this account more rapid, and after
extraction removes that portion of the iris which appears to have been
most exposed to bruising during the exit of the lens.
The operation of extraction may in many cases be either preceded or
followed by iridectomy, as proposed by Mooren, Von Graefe, and others.
The following operation seems to diminish the risks to a very great
extent:--
_Professor Von Graefe's Operation._--The lids are separated by a
speculum, and the eyeball is drawn down by forceps placed
immediately below the cornea. The point of a small knife, of which
the edge is directed upwards, is inserted at a point fully half a
line from the margin of the cornea near its upper part, so as to
enter the anterior chamber as peripherally as possible. The point
should not be directed at first towards the spot for
counterpuncture; nor till the knife has advanced fully three and a
half lines within the visible portion of the anterior chamber,
should the handle be lowered and the point directed so as to make
a symmetrical counterpuncture, which will give the external wound
a length of four and a half or five lines. As soon as the
resistance to the point is felt to be overcome, showing that the
counterpuncture is effected, the knife must at once be turned
forward, so that its back is directed almost to the centre of the
ideal sphere of the cornea, whether the conjunctiva is transfixed
or not, and the scleral border is divided by boldly pushing the
knife onwards and again drawing it backwards. This portion of the
operation is concluded by the formation of a conjunctival flap a
line and a half or two lines in length. A section thus made is
almost perpendicular to the cornea, a circumstance much
facilitating the passage of the lens, and the line of incision is
nearly straight, so that the wound does not gape. The iris should
be excised to the very end of the wound, and the capsule most
freely opened by a V-shaped laceration. Any lens, even the hardest,
may then be removed without the introduction of an instrument into
the eye, but Von Graefe's experience shows it to be advisable to
assist the evacuation by the hook in about one case in eight. In a
certain number of cases the lens will escape without difficulty
when the operator presses on the posterior lip of the wound,
especially when the back of the spoon is made to glide along the
sclera; should this not occur, Von Graefe uses a peculiar blunt
hook, or occasionally, though rarely, a spoon. A compressing
bandage is applied, and replaced at intervals.[88]
We are recommended to perform it in two sets of cases:--
1. Those in which the eye is known to be unhealthy and liable to
inflammations, specially of iris, retina, or choroid. In cases where the
patient has already lost an eye, Von Graefe thinks iridectomy should
always precede extraction. In the above, then, it is a precautionary
measure, and, if convenient, should be performed three, four, or even
six weeks before the extraction.
2. It is recommended to be performed at the same time as extraction in
all cases in which the operation has presented any special difficulties,
or has not gone smoothly, _e.g._ in cases where the lens has required
much force to expel it, either from the flap of cornea being too small,
or from adhesions between the lens and capsule; or, again, in cases in
which there is a tendency to prolapse of the iris, in which any of the
cortical substance has been necessarily left behind, or in which old
adhesions had existed between the iris and capsule, or between the
cornea and iris.
OPERATIONS FOR ARTIFICIAL PUPIL.--The cases are by no means unfrequent
in which it is necessary to remove or destroy a portion of the iris to
admit light to the retina. In cases of excessive prolapse of the iris
after extraction of the lens, where the iris has formed adhesions to the
wound, and still more frequently in cases where central opacities of the
cornea have fairly occluded the natural pupil, the only chance for
vision is to enlarge the old one, or make a new pupil by removal of the
iris.
Very various operations have been proposed, and exceedingly numerous and
complicated instruments invented for this purpose. We can notice here
only one or two of the most approved procedures:--
1. _Incision_ is the simplest.
This is practicable and effectual only in cases where the iris is so far
healthy as still to retain its contractile power, and so far free from
adhesions as to be able to make use of it. The best example of such a
case is that of a cataract, in which after extraction a prolapse of the
iris has occurred to such an extent as to obliterate the pupil, and
where, at the same time, the only adhesions are to the wound, none to
the cornea.
_Operation._--A double-edged needle is introduced through the cornea
near its margin; on arriving at the place where the pupil ought to be,
one edge is drawn against the iris, and divides it transversely, if
possible, without injuring the lens; the fibres of the iris start back,
contract, so that a sufficiently large central pupil may be obtained.
2. _Excision._--In the far more frequent cases in which there exist
adhesions between iris and cornea, or iris and anterior capsule,
incision is not sufficient, and it is necessary to excise a portion of
the iris.
The simplest and safest operation is the following:--
The patient recumbent, and the lids held apart by a speculum, the
eyeball should be steadied by the forceps of an assistant. A broad
cutting needle should then be introduced at the lower or outer edge of
the corneal margin. This must be very gently withdrawn so as to retain
as much aqueous humour as possible. Into the wound thus made the surgeon
must introduce the blunt hook (known as Tyrrell's) at first with its
point forwards, then, on arriving opposite the edge of the pupil, which
it is intended to enlarge or replace, with its point turned backwards,
so as to hook over the edge of the iris and thus drag on it. Once the
hook has fairly got hold, it must again be rotated forwards, and
withdrawn in the same direction as it was put in. The iris thus pulled
out of the wound is to be cut off with a pair of fine scissors, so as to
remove a sufficient amount to make a new pupil of the required size.
But in those cases in which the whole or greater part of the pupillary
margin is adherent, the blunt hook will not do, because there exists no
edge round which to hook it. One of two plans is generally chosen to
remedy this:--
(1.) A free incision made with a double-edged needle; through this a
pair of canula forceps is introduced, with which a portion of iris is
seized and dragged to the external wound; it can then either be cut off
or tied (see _Iridesis_); or,
(2.) A previous attempt may be made to free a portion to form an edge to
catch hold of, either by incision or by _Corelysis_ (_q.v._)
IRIDESIS.--_Critchett's Operation of Ligature._[89]--Patient being put
under chloroform, the ball is fixed by the wire speculum, and also by a
fold of conjunctiva being seized by forceps. An opening is then made
with a broad needle through the margin of the cornea, _close_ to the
sclerotic, just large enough to admit the canula forceps, with which a
small portion of iris close to its ciliary attachment is seized and
drawn out; a piece of fine floss silk, previously tied in a small loop
round the canula forceps, is slipped down and carefully tightened round
the prolapsed portion. This speedily shrinks, and the loop may generally
be removed about the second day. The chief advantage claimed for this
method is the ease with which the size of the new pupil can be
regulated. It is also suitable in cases of conical cornea, where it is
wished to change the form of the pupil into a narrow slit.
_N.B._--The ends of the ligature must be left sufficiently long to avoid
any risk of their being drawn out of sight into the substance of the
cornea, or even into the ball, by retraction of the fibres of the iris.
CORELYSIS.--_Freeing of the Pupil._--An operative procedure for
separating posterior adhesions of the iris to the lens. In it the
surgeon hopes to act, not on the iris, as in the operations for
artificial pupil, but only on the bands of false membrane which distort
the pupil.
The operation is briefly as follows:--The eye being firmly held by a
wire speculum, and forceps pinching up the conjunctiva, a broad needle
is passed rapidly through the cornea at a point which may give easy
access to the adhesion to be torn through. This point is generally at
the opposite margin of the irregular pupil, so that the needle may pass
through the cornea in front of the one side of the iris, then through
the orifice of the pupil, so as to reach the back of the other side. The
needle is withdrawn gradually, so as to lose as little of the aqueous
humour as possible, and then the spatula hook, called after the inventor
of the operation, Mr. Streatfeild, is introduced. It is used first as a
spatula, that is, with its blunt, though polished edge, to separate the
adhesions, and if this is unsuccessful, as a hook (FIG. XIV.), so as to
catch and tear them. In cases which resist the instrument used in both
of these ways, Mr. Streatfeild has used very fine canula-scissors to cut
the adhesions.[90] Such a further complication of the operation
practically alters its character into an operation for artificial pupil,
_q.v._
[Illustration: FIG. XIV.[91]]
IRIDECTOMY.--In cases of acute glaucoma, irido-choroiditis, and all deep
inflammations of the eye in which the ocular tension is increased, also
in certain cases of flap extraction already alluded to, the operation of
iridectomy as originally proposed by Von Graefe will be found of use.
_Operation._--The patient recumbent, and the eye absolutely fixed by
speculum and forceps, a linear incision, varying in length from
one-sixth to one-fourth of an inch, is made just at the margin of the
cornea. The point of election is the upper pole of the cornea. The lens
must not be wounded. The best instrument for making the section is an
ordinary linear extraction knife, bent at an angle to admit of its being
introduced from above. The iris will protrude through the wound, or, if
adherent, must be drawn out by forceps, and then is to be cut off with
scissors. The operation is rarely successful, unless a third, or at
least a fourth, of the iris be removed.
EXCISION OF A STAPHYLOMATOUS CORNEA.--There are certain cases in which
the whole or greater part of the cornea bulges forward in a great blue
projecting tumour. It is very ugly as it protrudes between the lids and
prevents their closure; besides this, from its exposure it frequently
inflames, even ulcerates, and has a most injurious effect on the other
eye. In the cases suitable for operation vision is completely gone,
without hope of its restoration by any operative procedure.
The best thing for the patient is to have just enough of the staphyloma
removed to enable the remains of the eyeball to form a good stump for an
artificial eye. Various means have been suggested for doing this,
varying in extent and severity from a mere shaving off the apex of the
staphyloma to excision of the whole eyeball.
By far the best method of operating is the one proposed and practised by
Mr. Critchett.
[Illustration: FIG. XV.[92]]
[Illustration: FIG. XVI.[93]]
The object of it is to remove an elliptical portion of the front of the
staphyloma, or the whole staphyloma, when it is possible, and at the
same time to prevent as far as possible the escape of the vitreous.
_Operation._--Three, four, or five small curved needles armed with
thread are passed through the staphyloma from above downwards, being
each entered a little above the line of the intended upper incision, and
brought out a little below the line of the intended lower one (Fig. XV.)
To remove the included elliptical portion, Mr. Critchett pierces the
sclerotic with a Beer's knife, just in front of the tendinous insertion
of the external rectus. Through this incision a pair of probe-pointed
scissors is introduced, and the piece cut just within the points of the
needles. On the removal, the needles, which have retained the vitreous
by their pressure, are drawn through and the threads cautiously tied.
Union by first intention very often occurs, and an excellent stump is
left with a narrow depressed transverse cicatrix[94] (Fig. XVI.)
EXTIRPATION OF THE EYEBALL.--1. _Of the Eyeball only._--A circular
incision should be made with curved scissors through the conjunctiva, a
little beyond the corneal margin, then, beginning with the external
rectus, muscle after muscle should be raised with the forceps, and
divided, after which the optic nerve is cut through with the scissors. A
slight preliminary extension outwards of the optic commissure will
facilitate the dissection, and must be secured with metallic sutures;
any vessels should be tied, and the orbit filled up with a light
compress of charpie secured with a bandage.
2. _Of the contents of the Orbit._--This may be required for malignant
disease, but with a very poor prognosis. The optic commissure should be
freely divided, and then, by bold strokes of curved scissors, or curved
probe-pointed bistoury, the orbit may be fairly emptied by scooping out
its contents. Even the periosteum may require to be scraped off, and the
optic nerve divided as far back as possible. The hæmorrhage may be
pretty smart, but can generally be easily checked by compresses; if
necessary, these can be soaked in the solution of the perchloride of
iron.
The author has done this operation many times, in cases extensive and of
old standing, for malignant disease, melanotic and encephaloid. All have
recovered, and in no instance has there been any trouble in stopping the
bleeding.
FOOTNOTES:
[81] _a._ Elliptical incision for entropium; _b._ wedge-shaped incision
for ectropium.
[82] Fig. VIII. illustrates Streatfeild's operation for entropium.--_a._
section of skin; _b._ section of levator palpebrae; _c._ section of
cartilage of lid; _d._ section of conjunctiva; _e._ wedge-shaped portion
excised.
[83] _Ophthalmic Hospital Reports_, vol. i. p. 121.
[84] Rough diagram of Bowman's operation, showing the grooved director
in the punctum, and the knife in the groove just before it slits up the
canaliculus.
[85] Diagram of operations for convergent squint--A A, line of
sub-conjunctival incision; B B, line of Dieffenbach's operation; C, wire
speculum.
[86] _The Radical Cure of Extreme Divergent Strabismus._ J. Vose
Solomon, F.R.C.S., 1864.
[87] _Ophthalmic Hospital Reports_, vol. iv. part ii. p. 197.
[88] _Biennial Retrospect_ for 1865-66. Syd. Soc. pp. 363-4. For a
thorough discussion of the merits of this operation, see papers by Von
Graefe in _Brit. Med. Jour._ for 1867, vol. i. pp. 379, 446, 499, 657,
765.
[89] _Ophthalmic Hospital Reports_, vol. i. p. 224.
[90] Streatfeild on Corelysis. _Ophthalmic Hospital Reports_, vol. ii.
p. 309.
[91] _a_ iris; _b_ lens; _c_ cornea. The hook is seen applied to the
adhesion between lens and iris.
[92] The staphyloma with the needles inserted, the lids held asunder by
a spring speculum. The elliptical dotted line shows the amount to be
removed; the vertical one, the position of the preliminary incision with
the Beer's knife.
[93] Resulting stump after the stitches are inserted.
[94] _Ophthalmic Hospital Reports_, vol. iv. part 1.