The Eye in its Relation to Health
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By Chalmer Prentice, M.D.
Chicago, A.C. McClurg & Company, 1895
Transcription (c) A. Wik, 2004

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        | Chapter XIV |  pages 189-194
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								189

THIS work is entirely confined to latent eye
defects and the repression of abnormal nerve-
impulse, and in no way is it intended as a text
book on refraction or ocular surgery.  Only one
operation is set forth, because it is new.  I think
it offers many advantages over all others for the
advancement of the recti.  In all advancement
operations the tying of the ligature is a question
of judgment, and at the best we can only approxi-
mate the required change of position.  By such
operations we can never hope to obtain anything
like absolute accuracy in the change of the
position of the eye, for the small difference of
one millimetre may mean several degrees of
deviation of the optic axes in one direction or the
other.  By my operation with the ligature plate,
the desired position of the eye will be attained
with much greater accuracy.
  The ligature plates are made of aluminum.
They are about three millimetres in width, vary
in length from about four millimetres to twelve
or more, and weigh from one-eighth to three-
fourths of a grain.  They are spherically curved
so as to fit the contour of the eye, their curva-

								190

tures being in varying diameters to meet the
requirements of different sizes of eyes.  The
plate is slightly notched at each end, with a
groove running from each notch its entire length
on the convex surface, into which the ligature falls
and is out of the way of producing any irritation.
  An incision is made through the conjunctiva
and capsule of tenon in the direction of the
muscle, and extending along its middle line,
beginning at its scleral attachment and extend-
ing as far as may be necessary.  The muscle
should then be entirely freed from its capsular
and ocular attachments.  A Stevens' hook is
then passed behind the muscle and traction made
toward the cornea; another hook is now passed
behind the muscle from its opposite side and
traction made in the opposite direction at the
same time.  The point of the second hook should
be forced outside of the capsule so as to expose
the muscle to view; a small curved needle carry-
ing one end of a ligature is made to enter one
margin of the muscle as far back from its scleral
attachment as is necessary, pass, as nearly as pos-
sible, transversely through its fibres, and come out
on its opposite margin.  This engages many more
fibres of the muscle than the passing of the liga-
ture directly through it.  It also offers a much
greater support to the ligature, there being much
less likelihood of its tearing away; in fact, it never

								191

has torn away in my experience.  After the
ligature has been so far placed, a portion of the
muscle can be cut away if it is deemed advisable.
Unless the amount of advancement be very con-
siderable, more than six millimetres, or one-fourth
of an inch, the operation will generally prove
fully as satisfactory without cutting the muscle.
Each end of the ligature on its respective side is
passed from the under side through the margin
of the muscle close to its scleral attachment.
After the two ends of the ligature have been
brought through these parts of the muscle, the
hooks are taken out.  Each end of the ligature on
its respective side is now brought through the con-
junctiva from its under side, at a point about three
millimetres in the direction of the cornea, from
the scleral attachment of the muscle and about
eight or ten millimetres apart, which the width of
the scleral attachment should determine.  The
exits through the conjunctiva should be from
three to four millimetres wider apart than the
width of the scleral attachment.  The two ends
of the ligature should now be carefully tied by
a surgeon's knot, not drawing the ligature so
tight as to draw or pucker up very much the con-
junctiva that it engages.  Not much drawing for-
ward of the muscle should be attempted in the
first tying of the ligature, it should be just
tight enough to insure the taking up of all slack

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in the ligature.  Or, where the conjunctival
exits of the ligature were about eight millimetres
apart, the tightening should be sufficient to draw
them within about four millimetres of each other.
The knot should be very carefully and firmly tied.
Two strabismus hooks may now be used or a
ligature dilator made for the purpose, and the
muscle may now be advanced by traction in
opposite directions.  By this process the operator
can now see about what length of a ligature plate
should be used; accordingly he firmly seizes the
plate with a pair of forceps made for the purpose,
and makes one of its notched ends to engage one
side of the ligature.  A somewhat strong Stevens'
strabismus hook is now used to make traction on
the opposite side of the ligature, and to slip it
over into the notch on the other end of the liga-
ture place.  The forceps and hook are now
removed and the ligature and knot fall into the
groove on the ligature plate, so that there is no
possibility of its coming in contact with the con-
junctiva and giving rise to even that amount of
irritation that an ordinary ligature does.
  An examination can now be made to ascertain
the exact position of the eye and the amount of
advancement that has been accomplished.  If it
is not sufficient, a ligature plate of greater length
can be made to replace the first.  If too much
advancement has been made, a shorter ligature

								193

plate can be used.  The ligature plate of a proper
shape and carefully made never gives rise to the
slightest irritation; its presence is not even felt
by the wearer.  It should be left in for three or
four days.
  When the operation is made without cutting
the tendon, the muscle is tucked or folded upon
itself, and the inflammatory action that follows
fastens it in this position.  The slight bunching
or enlargement that results from the folding
soon entirely disappears by absorption.  After
that stage of the operation where the ligature has
been passed through the muscle the first time, a
portion of the muscle can be cut away if it is
deemed advisable.  Unless the amount of ad-
vancement is very considerable, the operation
will generally prove fully as satisfactory without
cutting the muscle.  By this operation I have
changed the position of the eye 30 deg. without
cutting the muscle.
  Modifications of the above operation can be
advantageously made in which this plate is still
very useful.  Where the conjunctiva is sufficiently
strong to withstand the necessary traction, that
stage of the operation where the ligatures are
passed through the muscle at its scleral attach-
ment, may be left out, so that, after the ligature
has been passed through the muscle far enough
back, the two ends may be brought out through the
	12

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conjunctiva on their respective sides, eight or ten
millimetres apart, as close to the cornea as possi-
ble.  If the conjunctiva is sufficiently strong to
stand the dragging, the ligature plate prevents it
from puckering up, and offers the advantage of
increasing or lessening the effects of our opera-
tion, at the same time hiding the ligature from
any touch with the palpebral conjunctiva.  In all
the old operations, after the ligature has been
tied, if the position of the eye is not satisfactory,
any alteration involves a new ligature and another
operation; whereas with the ligature plate these
alterations can be made by substituting plates of
different lengths.






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        | End of Chapter XIV |  pages 189-194
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