Casey A. (Casey Albert) Wood.

The American encyclopedia and dictionary of ophthalmology (Volume 3) online

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ditions to produce abortive lenticular cells. This is especially true
where the anterior capsule overlies the posterior capsule,' these cells
subsequently becoming sclerosed and opaque.

Another frequent source of after-cataract is small masses of cortical
lens-matter that remain behind when the lens is extracted. These
subsequently undergo absorption, but at their seat there is found a
dense connective-tissue-like material. Bates, from experimental work
upon rabbits, drew the conclusion that the fluid which replaced the
normal aqueous humor not only contained albumin, but would clot,
and that such clots when stained and examined by the microscope
showed the structure to be of fibrin. He deduced from these experi-
ments that probably a fibrinous connective tissue process followed on
the capsule from loss of the aqueous humor during cataract extraction.
It is well known that when the wound of a cataract extraction does
not close promptly, so that there is a considerable leakage of aqueous
for a number of days, these opacities on the posterior capsule are
much more likely to occur. This fact would seem to confirm Bates'
deductions.

These opacities very often take the form of bands stretching across
the pupil in a direction approaching vertical. The capsule itself is
elastic, and these bands tend to contract ^nid draw the elastic mem-
brane tensely across the area of the pupil.

Another variety of simple after-cataract is due to former disease of
the capsule itself, in cases of old and complicated cataract.

When, following cataract extraction, we have an iritis or an irido-
cyclitis, the result complicates the simple after-cataract by pouring
out upon the surface of the capsule an exudate from the iris. This
exudate forms dense opaque masses at the border of the pupil, gluing
it to the capsule at such places, and if thu iritis has been profound
the whole margin of the iris may in this manner be agglutinated to the
capsule. The pupillary area becomes much diminished, and if the
iritis is complicated with ciliary inflammation in the neighborhood of



CATARACT, SECONDARY



1577



the original wound, the iris may be drawn np and attached by inflam-
matory material in such a manner that the lower border of the pupil
is dragged to the upper margin of the anterior chamber. The conse-
quent stretching of the iris tissue approximates it to the capsule to
which it becomes firmly adherent, with the result that a dense, inflam-
matory membrane of iris tissue, connective tissue and posterior capsule
is stretched across the anterior chamber. — (M. S.)



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Secoiidaiy Cataiact with Epithelial Proliferation. (Elschnig. )



Edgar S. Thomson (Archives of Ophlhal., May, 1909), believes that
secondary membranes are due to: (1) unremoved cortex from the
equator of the lens enclosed by apposition of the posterior capsule
with the remains of the anterior capsule, and so protected from the
solvent action of the aqueous; (2) connective tissue formation from
iris fibroblasts due to iritis, slight or severe.

The unremoved cortex invariably increases in volume by prolifera-
tion and may become infiltrated with leucocytes and fibroblasts. Later,
the mass undergoes retrogressive changes, resulting in connective tissue
formation and contraction. These contraction bands, liidden behind
the iris, exist very frequently. They do not necessarily give rise to
trouble, perhaps because the changes are slow, and our patients often
old, but they may (1) pull on the ciliary body causing those appar-
ently spontaneous attacks of cyelitis which occur with a clear pupil,
and which even go on to glaucoma; (2) relax the membrane so that
it wrinkles, and causes irregular refraction of light rays: (3) form,
when accompanied by slight iritis, the well-known connective tissue
memliranes of varying density across the pupil.



1578



CATARACT, SECONDARY




Linde 's After-Cataract Scissors.




Secondary Cataract Instrument of Liier.

It is entered while closed, the secondary niemlnane is pierced by the arrow-
pointed end, the blades are then opened wide and a cut made through the obstruc-
tion to vision.




Levinsohn 's Forceps-Scissors for Secondary Cataract.




Secondary Cataract Instrument (Punch) of Kriiger,





Weber's (Eight and Left) Cajisule Hooks, for the Extraction of Capsular Remains.




Pley 's Capsular Forceiis, for Secondary Cataract.





Guarded Hook (Panas) for Eemoving Capsular Debris in Secondary Cataract.



CATARACT, SECONDARY



1579



To counteract these evil consequences he advocates making as large
a crucial incision with the cystotome as possible, to expose the cortex
thoroughly to the aqueous ; washing out the capsule after every extrac-
tion ; and controlling inflammation of the iris as far as possible by
the early and judicious use of ice and atropine. His after-treat-




Bourgeois' Capsulectomy Forceps.



^^




Wilde's Capsular Scissors for Secondary Cataract.




De Lapersonne 's Capsulo-iridotome. A Punch for Use in Secondary Cataract.

ment of the opaque membranes is on the usual orthodox lines, but he
points out that it is advisable not to judge the density of the mem-
branes only by the appearance, but to consider also the amount of
iritis that followed the extraction, the amount of cortical material that
was left to be absorbed, and the length of time since the extraction.

Operative treatment. Linde has invented a modified de AVecker's
scissors in which a short, blunt pointed but cutting blade fits into a
longer pointed one. A small corneal wound is made with a kera-
tome in such a fashion that no aqueous escapes. The point of the
keratome should at the same time make an opening in the after-
cataract. The closed instrument is now introduced through cornea
and cataract, and, on opening, it makes easily and without irritating
the iris, a clear pupillary space.

Bourgeois' capsulectome is an instrument intended to be used
in operating on secondary cataract, especially that found after ex-
traction without iridectomy, the obstructing membrane being re-
moved by a combination of siezure, cutting and torsion ; not by drag-
ging or pulling. An opening 3 mm. wide is made with a keratome



1580 CATARACT, SENILE

or similar instrument, and the point of the capsulectome introduced
closed. It is now opened by simple pressure on the branches of
the instrument until the margin of the pupil is reached by the
blades. They are then allowed to close, when it will be found that
a portion of the opaque membrane is caught between them. The
instrument is then slowly withdrawn from the anterior chamber with
a rotary movement, when the opaque capsule included between the
blades will be cut ofif and removed without damage to the iris.

For the treatment, generally operative, of this condition, see, also.
After-cataract.
Cataract, Senile. Under the general heading of Cataract, the symptoms,
prevention and non-operative treatment of senile cataract have been
to some extent considered, but it is proposed in this section to say some-
thing more not only on these topics but on others connected with the
subject that have been referred to there and elsewhere. The classic
work of Otto Becker (Zur Anatomic der gesunden und kranken Linse,
1883), or the later monograph of Louis Strieker {The Crystalline Lens
System, Cincinnati, 1899) based on it should be consulted by the
reader as an introduction to the study of senile cataract. In recent
years other treatises (by Greetf, Parsons, Treacher Collins, Dor, Hess,
Herbert) are at hand to supplement these earlier works.

Hard or senile cataract, gray cataract, is the commonest as well as
the most important form of the disease, the cortical variety being most
frequent.

The normal lens gradually grows larger and denser as we grow
older and exhibits other senile changes; the lenticular nucleus in par-
ticular becomes firmer, and with the rest of the lens acquires a yellow-
ish tint and transmits less light than formerly.

One should not assume from the name commonly given to this form
of crystalline opacity that it represents a change more or less normal
to increase of years — like gray hair or wrinkles — but that it is always
a disease and generally a serious disease with definite pathological
lesions. However, since these changes are rarely encountered before
the age of fifty it is, and has long been, an established custom not to
speak of opacities in the lens as senile when they appear prior to that
age.

•The pathology and morbid, anatomy of senile cataract has been dis-
cussed in Volume II, p. 1447 of this Encyclopedia. Louis Dor believes
this form of acquired cataract to be due to hydration of the lens and,
in consequence of this process, absorption and disappearance of the sol-
uble crystalline albumins. This degenerative process is in its turn due
to certain causes producing hydration by the flowing of a watery cur-



CATARACT, SENILE 1581

rent into the lens substance through a form of (morbid) osmosis. This
double process, when it is not attributable to a modification of normal
physical conditions (excessive heat, light, electricity) is the result of
penetration into the lens substance by watery ferments or cytolythic
serum. This penetration is made possible by certain changes in the
subcapsular cells, often corresponding to alterations in the epithelial
structure of the ciliary body. Black cataract is a phenomenon of oxida-
tion rather than of hydration. In those senile cataracts whose nuclear
coloration is yellowish, brown or black, but in which the cortex appears
white, there is both dehydration and oxidation.

W. E. Burge {Archives of Ophth., Sept., 1909) has analyzed the
ash of l)oth normal and cataractous lenses. Tables giving analysis of
the normal human, the pig's, and of cataractous lenses are reported.
The pig's lens was found to be almost identical in the percentage of
the ash with the normal human ; and most of the comparisons are
drawn from this and the human cataractous lens.

Burge concludes that in senile cataract the percentage of potassium
is greatly reduced, while calcium and sodium are increased, thereby
bringing the lens nearer to the composition of the blood and the lymph.
He also finds that the normal lens in old age compared with the embryo
does not show any percentage diminution of potassium. From this the
author argues that senile cataract is not premature senility of the
lens, i. e., the acceleration of the normal senile change ; but is due to
some cause which has interrupted the normal metabolism, and brought
on a moribund condition of the tissue. As a confirmation of this
theory is the curious fact that the cataractous lenses obtained from
India contain a large amount of calcium, potassium and sodium silicate,
while those from the United States are without silicates. Is there
something in the diet of the East Indians to account for this curious
condition'?

A. E. Elschnig {Klin. Monatshl. f. Augenheilk., January, 1911) has
recorded the morphologic conditions of lenses extracted for senile cata-
ract ; in all 224. They were placed in a white porcelain dish, filled with
physiologic salt solution, with a black glass plate, graduated in milli-
meters, at the bottom. By alternately bringing the lens, with a cataract
spoon, on the white or black part of the bottom the transparency of cor-
tex and nucleus could be sufficiently well ascertained.

A general examination of all cataract patients is made by Elschnig.
and only uncomplicated senile cataracts, with a lowest age limit at 45
years, are considered in the following 6 groups: 1. Total cataract with
grayish-yellow or white nucleus and more or less uniformly opaque cor-
tex of grayish or yellowish-gray color. 2. Brownish or broM^iish-gray



1582 CATARACT, SENILE

nucleus with more or less dense grayish or yellowish-gray cortex. 3.
Cataraeta (bruneseens) nigra. 4. Pure cortical cataract without visible
nuclear opacity. 5. Opacity of the cortex similar to zonular cataract
with clear nucleus. 6. Pure opacity of the nucleus, nuclear sclerosis,
the cortex being perfectly transparent or with very faint spokes at the
surface. 1 and 2 correspond to the subcapsular cataract of Hess, with
the difference that the nucleus is also opaque. The great frequency of
nuclear cataract in the above named writer's statistics is due to the fact
that he entirely excludes the so called "maturity" of cataract from the
indication for operation. In clinically pure sclerosis of the nucleus the
latter showed the faintest gray coloration or opacity on transillumina-
tion with the plane mirror. After extraction Elschnig considers the
examination of opacities of the lens in vivo, as long as they are partial,
with the plane mirror and loupe far superior to any other mode, even
to that with the corneal microscope. No relation between age and form
of cataract could be ascertained, although it seemed that total cataract
with brownish nucleus usually occurred in older individuals, and that
cataract with gray or white nucleus occurred more often in younger
ones. Elschnig confirms the observation of Handmann that senile cata-
ract almost regularly commences in the lower half of the lens.

The author proposes the following modifications of Hess' nomen-
clature of cataract : 1. Cortical cataract without opaque nucleus, sub-
divided into subcapsular and supranuclear cortical cataract. 2. Nu-
clear cataract, frequently commencing as sclerosis of the nucleus. Both
forms are not stationary and may pass into 3, the regular senile total
cataract with its regressive metamorphosis: finally cataraeta brunes-
eens, or nigra. The term "incipient cataract" is to be discarded and
replaced by the correct signification of the form of cataract ; nuclear
(cortical), subcapsular and supranuclear; finally, incipient, total,
where the epithet "senile" would specify the etiology.

Later. Elschnig and Zeynek {Wien. Klin. Woch., January 10, 1913)
report that among 1,500 cataract extractions, in the last five yeai*s,
there was only one case of cataraeta nigra, and seven cases of cataraeta
bruneseens. The lens of cataraeta nigra was very hard. The outer
lamellfB were colorless, the inner ones yellowish brown and transpar-
ent. They became entirely transparent after treatment with glycerine;
microscopically no pigment corpuscles were observed. This fact prob-
ably induced some authors to consider the coloring of cataraeta nigra to
be due to an increased density and sclerosis of the lens fibres. There,
however, was possible witli a 3 per cent, solution potassium hydrate to
extract a brown pigment. It is probable that this pigment is produced



CATARACT, SENILE 1583

by a change and destruction of some albumen corpuscles brought about
by digestive disturbances.

AV. Reiss has endeavored (abstract iu Ophthalmology, Oct., 1913,
p. 10!)) to establish the histological differences between the mature and
the immature fibres of senile cataract by a chemical te'st. However,
he regards the maturity of cataract as mainly a clinical conception, and
agrees with Landolt that we should substitute for the maturity of a
lens, the idea of its operability.

The pathological examination of lenticular opacities is fraught by
many difificulties. There has not yet been found a reliable liquid for
preserving and fixing the lens, which constantly loses its form, dimen-
sions and structure. Cataracts obtained for histological purposes by
operative means are usually minus their capsule, whose epithelium is
one of the starting points of cataract and an important seat of patho-
logical lesions.

For the better determination of the state of maturity of senile cata-
ract, Reiss resorted to the eysteinic reaction discovered in 1910 by
Arnold and used in the biochemical examinations of various albuminoid
bodies in the human organism. His method is as follows : Crush and
spread upon a piece of blotting paper l)y means of a spatula, the lens
to be examined. After drying in an oven, a few drops of a 5 per cent
solution of nitro-prusside of sodium are added. When this thin film is
touched by a glass rod dipped in ammonia there is produced — in the
normal lens — a deep purple color. In unripe cataracts, the opaque
particles do not give this color reaction. Reiss, relying upon his numer-
ous investigations, concludes that a negative result of the eysteinic reac-
tion in the cortical masses as well as in the nucleus constitutes a valu-
able objective sign of the maturity of senile cataract.

A. Jess (Archives of Ophthalm, Jan.. 1913) has added a number of
observations to the researches of Reiss. He finds that in the normal
lens there is no difference in the behavior of the peripheral and of the
central layers to this reaction, and that in senile cataract the reaction
disappears entirely or in part. Traumatic cataract behaves like a nor-
mal lens. In hypermature cataract, the reaction is entirely wanting.
In immature cataract the cortex nearly always reacts plainly, and even
in some cases the nucleus also. The age of the patient has no effect
on the reaction. Jess is also able to confirm Alorner's statement of the
presence of a considerable amount of insoluble albumin in the lens.

It is known that cataract in a person having a blue and a brown
eye (heterochromia iridis) always develops in the blue eye; or if the
eyes be of the same color and the iris of one be lighter in shade than
the other, that it first attacks, or may attack only, the lighter-colored



1584 CATARACT, SENILE

eye. Puchs believes that in the absence of other causes, this must be
regarded as something connected with the lack of pigmentation in the
lighter eye ; it being assumed that a disturbance of nutrition is at the
})ottom of both morbid conditions. It is true that nothing more definite
than this is known regarding such a disturbance of nutrition ; but that
it is present is clear from the fact that in the lighter-colored eyes we
[nearly] always find the evidence of a chronic eyclitis in the form of
very minute deposits.

The alterations in the crystalline lens that one finds in hard or
senile cataract are at first generally confined to the cortex ; the nu-
cleus and peripheral epithelium are later involved. A clear fluid,
eoagula and IMorgagnian globules are found between the unaltered
fibres, so that even if there be shrinking of the nuclear portion, the
cataractous lens is often larger, as a whole, than normal. Alt believes
that some of the intraocular fluid finds its way through the capsule
between the lenticular fibrils, and that the wedge-shaped opaque
areas are due to the arrangement of the lens-star. So far as the
microscope is concerned it reveals in the earlier and medial stages
of hard cataract, vesicular cells, Morgagnian globules and coagulated
deposits, as well as fibres that are spindle- and club-shaped. Although
there may be no alterations in the epithelium, yet the fibres at the
equator are often destroyed early, so that the degenerated cells extend
towards the posterior capsule and even line it. As the morbid changes
proceed the spaces between the fibrils become filled with eoagula,
large irregular spaces are formed and at last the whole cortex is
converted into an opaque mass. Finally, cholesterin and chalky
material may be deposited. A portion of the lens matter becomes
absorbed, the contents may fall away from the capsule and the sub-
capsule space filled by a thin layer of fluid. Clinically, the cataract
is then said to be mature or ripe.

In hypermature cataracts there is often thickening of the anterior
capsules, due to proliferation of the anterior epithelium. Still later,
the lens substance may become absorbed and replaced by fluid, in
the midst of which the nucleus floats free — thus constituting Mor-
gagnian cataract (q. v.).

As a consequence of these changes cataractous lenses vary greatly
in diameter — a matter of much importance in connection with the
length of the incision for their removal. It must be remembered that
this diameter is rarely less than 10 mm. in the ordinary form of
opaque lens.

Handmann (Klin. MonatsM. f. Augenheilk., Dec, 1909) has made
a point of recording exactly in all cases of cataract the nature of the



CATARACT, SENILE 1585

opacity, its position as regards cortex, nucleus, pole or equator, and,
in the case of peripheral opacities, the segment of the lens in which
they were situated ; and made the discovery that the first indications
of senile cataract appeared with much greater frequency in certain
quarters of the lens periphery than in others.

His figures concern 845 eyes with senile cataract, in which the opac-
ity could be called incipient in the sense that some portions of the
lens were still transparent ; there were 1147 opacities or groups of
opacities, which were distributed in the regions of the lens in the
following manner: Lower, 335; lower nasal, 118; lower temporal,
35 ; upper, 32 ; upper nasal, 14 ; upper temporal, 15 ; nas,al, 111 ; tem-
poral, 67 ; diffuse, 65 ; whole periphery, 89 ; central, 220 ; supranuclear,
26; doubtful, 22.

Excluding the more advanced cases and taking only those which
presented no more than one or two opacities, with normal or nearly
normal visual acuity, the figures were for 391 peripheral opacities:
Lower, 319 ; upper, 21 ; nasal, 40 ; temporal, 11.

Having thus shown the marked preponderance of the earliest signs
of senile cataract in the lower half of the lens he discusses the infer-
ences which may be drawn from the fact. We know that adventitious
substances, such as blood and pus, tend to collect in the lower part of
the anterior chamber, and we may assume that pathological products
and excreta so far as they are specifically heavier than the aqueous
will take the same position, and the lower half of the lens will thus be
less favourably situated as regards metabolic changes than the upper.
Another possible factor in the production of senile cataract is the
influence of the ultra-violet rays on the lens. Such rays have been
shown by Widmark, Hess and others to be capable of producing de-
structive changes in the lens fibres (as well as in other tissues of the
eye) and it is obvious that in the ordinary occupations of life the lower,
and perhaps especially the lower-inner, parts of the periphery of the
lens will be more exposed to light rays than the upper.

Taking these facts in conjunction with his present observations
Handmann is inclined to view the latter as a proof that senile cata-
ract arises from certain disturbances of the nutrition of the lens which
make themselves felt more readily in the lower than in the upper
part of the lens.

Do cataracts due to other causes show a similar localization? The
author's figures bearing on this point are naturally much smaller than
those for senile cataract, but so far as they go he considers that his
statistics for diabetic and glaucomatous cataract show that the changes
in the lens in such cases are more apt to be diffused and exhibit no



1586 CATARACT, SENILE

marked preponderance in any particular region. (Abstract, Oph.
Review, May, 1910.)

Classification of senile cataract. Axenfeld {Lehrhuch cler Augenheil-
hundCy 3rd Edition, p. 504) and some other writers divide the various




Incipient Subcapsular Senile Cataract. (After Axenfeld.)

> \



,; — ___„ ni



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z'"^';,, :,'*':



iM



Mature Subcapsular Senile Cataract. (After Axenfeld.)

d, Fine-celled debris; /, free cells; /t, empty spaces (or filled with clear fluid)
between the lens fibres; fe, capsular cataract; m, Morgagnian granules; p, false
epithelium on the posterior capsule; v, clear spaces between the capsule, epithelium,
and normal lens fibres. The nucleus of the lens is normal.



CATARACT, SENILE



1587



fori^is of senile cataract into sub-varieties, although they admit that
these forms are very often combined or gradually shaded off the one
into the other. The Axenfeld subdivision is into (a) subcapsular cor-
tical cataract, (b) supranuclear senile cataract, and (c) nuclear senile
cataract. The most common form is the subcapsular, divided into four
categories, according to the progress made by the advancing opacity,
into (1) catar acta subcapsularis incipiens, (2) cat ar acta subcapsularis
immatura, (3) cataracta subcapsularis matura, (4) cataracta subcapsu-
laris hypermatura. These different forms are pictured in the text.




Hyperniature Subcapsular Senile Cataract. (After Axenfeld.)



Online LibraryCasey A. (Casey Albert) WoodThe American encyclopedia and dictionary of ophthalmology (Volume 3) → online text (page 8 of 77)