The Pulley Method 
OF 
ADVANCING THE RECTUS, 
WITH 
Indications for Its Employment. 
BY. 
A. E. PRINCE, 
Jacksonville, III. 
Ophthalmic Review, Sept. 1887, 
and 
St. Louis Mid. and Subo. Jouk., March, 1888. Advancement of the Recti and Indications for Its Employment. 
A. E. Prince, Jacksonville, 111. 
The preparation of this article is prompted by the con- 
viction that the importance and success attending the 
operations for advancement of the recti muscles are incor- 
rectly estimated, patients being subjected to repeated tenoto- 
mies for convergent squint, when an advancement of the 
opposing externus would have at once corrected the defect. 
This conviction is further strengthened by the acknowl- 
edgment of several members of the 9th International Medi- 
cal Congress, that the correction of the strabismus is not yet 
a satisfactory operation. Want of confidence in the surgical 
treatment of strabismus is still further shown by the willing- 
ness of many oculists to be satisfied with a partial correction, 
and by the not uncommon maxim that it is better to leave a 
slight internal squint, than to risk getting an over correction. 
Another maxim, which I believe arises from the lack of confi- 
dence in former operations for advancement, is, that but one 
eye should be corrected at a time. This is but the natural 
corollary of the assumed danger of over-correction. 
It is my belief that if the operation of advancement of the 
rectus were more studied and oftener practiced, according 
to the indications which will follow, less apprehension would 
attend an over-correction than an under-correction, for in the 
latter event it is found the simplest matter to insert a limit- 
ing advancement suture at the time of the operation, which 
will advance the divided tendon with mechanical precision; 
whereas, to increase the effect of a tenotomy for internal 
squint by the further laceration of the capsule, is inaccurate ADVANCEMENT OF THE RECTI. 
3 
and often directly harmful, for even when successful in re- 
storing parallelism, it does so at the expense of the power of 
lateral motion, and is at times productive of asthenopia, and 
at others followed by subsequent divergence. 
The same objections hold against the insertion of a suture 
to increase the retraction of a tenotomized muscle beyond that 
which is effected by the natural contractility of the muscle 
itself. The effect of this measure can never be calculated, 
and is, fortunately, too seldom efficient to be often practiced. 
In conformity with the principles of mechanics, surgery, 
and common sense, when the internal rectus has been tenoto- 
mized and caused to retract to the limit permitted by the 
capsule, the efficiency of the opposing muscle should be 
increased by shortening or attaching it at a more anterior 
point, thus equalizing the relative lateral power of both recti, 
and thus reinstating, rather than disturbing, the normal 
condition. 
The tardiness with which the operation of advancement 
has been accorded the position of importance which it de- 
serves, as the frequent accompaniment of tenotomy and the 
reliance in every case of extreme deviation, is largely due to 
the insecurity and inaccuracy attending the early forms of 
operation, as well as those which have been offered since its 
original conception by Gurin, in 1849. 
The principal defects of all these operations are regarded 
by the author as depending on one of two causes: 1°. The 
manner of suturing the muscle : 2°. The manner of attaching 
the muscle to the ball. 
The anatomical reasons for this are evident, viz: 
1°. The fibres of the rectus muscle are held together by 
a very frail connective tissue which permits them to be 
separated by a small force. The threads which are inserted 
through the muscle near its cut end, have a great splitting 
power, met by no corresponding resistance on the part of the 
inter-fibrillary tissue and theca, and since the retracting power 
of the muscle is very considerable, there is always danger 
that it will escape from a suture so placed, and retract to such 
an extent as to cause the loss of power over the globe. 
2°. The second anatomical defect is found in the feeble 
resisting power of the conjunctiva, which is the medium, 
usually employed, of attachment to the eye-ball. 4 
ADVANCEMENT OF THE RECTI. 
Though this tissue is freely supplied with bloodvessels, 
its resistance to the cutting tendency of sutures is compara- 
tively slight, hence it is observed, that, while in the main the 
sutures do not cut entirely out, yet there is more or less 
retraction of the muscle advanced, often resulting in a par- 
tial or complete failure. 
Whenever two or more independent sutures are employed 
to attach the muscle to the globe, the loosening or tightening 
of all of them would be required to change the effect, if it 
should be found too little or too great after the muscles 
have recovered the normal motive power, which is usually 
somewhat impaired by the manipulative violence. It has, 
moreover, not infrequently happened, in tightening the 
sutures, when only two were used, that the tendon, or divided 
end of the rectus would be displaced above or below the plane 
of its physiological activity, causing an upward or downward 
deviation of the optical axis. 
The operation of the author appeared originally in this 
Journal, June, 1881, and in a modified and improved form in 
the N. Y. Medical Record, Aug. 8, 1885, and further simplified 
and perfected in the following text of the British Ophthalmic 
Review, Sept., 1887. 
“In devising this operation the three points aimed at 
have been: 
(1.) To secure an unyielding anterior fixation point by 
utilizing the dense episcleral tissue. 
(2.) To avoid the danger of splitting the theca and conse- 
quent escape of the muscle, by the formation of a loop suture 
enclosing the middle portion of the rectus together with a 
corresponding width of capsule and conjunctiva, the cutting 
tendency of which should be reduced to a minimum by being 
made transverse to the direction of the muscular fibres; and 
(3.) The formation of a knot, which, while avoiding the 
danger of vertical displacement, would secure precision in the 
maximum as well as the minimum degrees of deviation and 
insufficiency, and at the same time be subject to modification 
after the recovery from chloroform or the paresis which 
attends manipulation. 
Operation. 
Preliminary Tenotomy.—In high degrees of deviation, ten- 
otomy of the opposite rectus is made for the double purpose 
of increasing the effect, as well as that of equalizing, on the ADVANCEMENT OF THE RECTI. 
5 
two sides, the cicatrization, thus preventing consequent 
deviation. 
Pulley Suture.—Fig. 1, a. The eye being fixed, the anchor 
or pulley suture a, is introduced slightly into the dense tissue, 
one millimetre from the corneal margin1, with a very sharp 
slender curved eye-needle.—(No. 25, Tiemann, N. Y.) 
Fig. 1. 
Separation of the Tendon.—The conjunctiva and capsule of 
Tenon having been divided, one branch of the advancement 
forceps (Fig. 4) is introduced underneath the tendon of the 
rectus, and the other closed upon it, securing the edge of the 
retracted conjunctiva, after which the tendon is separated 
from the sclera. 
Loop Suture.—Fig. 1, b. Each end of a thread being armed 
with a needle, both are passed from beneath the elevated 
rectus, through the capsule, muscle and conjunctiva, enclos- 
ing the middle portion of the rectus in a loop, from which it 
cannot escape. The tissues in the grasp of the forceps are 
now divided two millimetres anterior to the loop suture, the 
location of which will depend on the amount of advancement 
required in each individual case. 
In the absence of an efficient advancement forceps, this 
suture may be introduced by opening the conjunctiva and 
1.—Since the publication of this operation information has been obtained 
that Gurin originally employed the scleral attachment, but it has been thought 
dangerous by most subsequent surgeons, and the uncertain attachment to the 
conjunctiva preferred, for reasons which do not exist since the introduction of 
aseptic methods. The scleral suture is endorsed by H. Knapp, who has em- 
ployed it for many years to increase the effect of a tenotomy. 6 
ADVANCEMENT OF THE RECTI. 
capsule parallel with the margin of the rectus, elevating the 
muscle on a strabismus hook, and suturing it together with 
the capsule and conjunctiva before separating the tendon. 
Advancement.—Fig. 2. One end of suture b is crossed over 
suture a, both ends of which are now brought together and 
securely tied, enclosing the former in a loop or pulley. Both 
ends of b are now brought together in the form of a surgical 
knot, and it becomes apparent that in proportion as they are 
tightened over the pulley formed by a, will the cut end of the 
rectus be advanced, simultaneously closing the conjunctival 
gap. 
Fig. 2. 
To obtain the most perfect correction, a bow-knot is 
tied, or the threads twisted together to prevent slipping, and 
time allowed for recovery from the effect of traction, which 
should, as much as possible, be avoided during the operation. 
After this, the knot may be secured, or the effect increased or 
diminished as conditions may indicate. 
Quite the same effect may be obtained by reversing the 
order of the sutures and making the scleral attachment with 
the needle at one end of suture b, in which case the pulley 
will be formed by the bridge of dense scleral tissue. (Fig. 3.) 
Fig. 3. 
This plan has been adopted in some of my later operations ADVANCEMENT OF THE RECTI. 
7 
and is thus preferred in St. George’s Hospital, London, and 
in some of the German hospitals where it has been adopted. 
Limiting Tenotomy.—The conception of a sliding suture, 
enabling the operator to regulate the effect to any desired 
Fig. 4. 
degree, removes much of the uncertainty attending 
tenotomies in cases of insufficiency and diplopia. 
There being no cause for ex-section, a curved needle 
is passed into and out of the tendon, subsequently 
dipping into the sclerotic in the reverse direction, 
thus forming sutures b and a with one continuous 
thread. The tendon is then completely divided 
without anxiety from over-correction, for, should it 
occur, the surgeon has but to limit the effect by 
tightening the suture when the tendon is advanced as 
may be required. 
The remaining difficulty which has been experi- 
enced in these operations is the recovery of a muscle 
retracted from a previous operation. To accomplish 
this a curved needle (Fig. 5) has been devised, which 
will be found useful in various operations on the conj- 
unctiva. It has a short spiral curve with an eye in 
the point, through which the thread passes after leav- 
ing the spool, and as now made by Tiemann, New 
York, and Weiss, London, it will fit into any eye case 
and may be always threaded and ready for use.” 
Indications. 
The following indications for the employment of 
advancement have stood the test of observation and 
experience since their original publication in the 
Saint Louis Medical and Surgical Journal June, 
1881. They are conveniently classified in the following 
groups: 
1°. In the correction of binocular diplopia, the ease 
and accuracy with which the effect can be increased or 
Fig. 5. 8 
ADVANCEMENT OF THE RECTI. 
diminished render this method of advancement especially 
available. 
2°. In case of convergent strabismus, measuring by 
Landolt’s method* less than 15°, ametropia having been 
eliminated or corrected, the effect of a tenotomy would some- 
times be an over-correction. In such case the suture should 
be inserted as a safeguard against over-correction, and em- 
ployed, should occasion require, to diminish the effect. 
3°. In case of internal squint exceeding 15°, in which 
from any cause the operation is confined to one eye, a simple 
tenotomy of the internal rectus will seldom secure a constant 
correction. In such case an increase of the effect is best 
obtained by a requisite advancement of the externus. 
4°. The sanfe rule applies to an inward deviation ex- 
ceeding 30°. A simple tenotomy of both interni without 
excessive laceration of the capsule will seldom suffice. In 
such case an advancement of one or both external recti will 
usually be required to effect an enduring parallelism. 
5°. In case of external squint exceeding 10°, a simple 
division of both attachments of one external rectus will seldom 
effect parallelism, and as convergence is usually impaired a 
requisite advancement of the internus is to be made. When 
each eye diverges, exceeding 10°, a double internal advance- 
ment is indicated. 
6°. In case of divergent squint, (the previous condition 
having been convergence,) following tenotomy, H. not having 
been corrected ; or from excessive laceration of the capsule 
allowing the tendon to recede back of the equator; or from 
accidental myotomy—an advancement of the retracted muscle 
is imperative. If of long standing, its efficiency will be impair- 
ed and a tenotomy of the opposing externus will be required. 
When the muscle cannot be secured, a myotomy or an exsec* 
tion of the anterior end of the externus will equalize the inef- 
ficiency and restore parallelism, and besides secure from 20Q 
to 45° of lateral motion, through the action of the retracted 
muscles on the capsule of Tenon or the orbital cellular tissues. 
This has been observed in six cases. 
In these latter cases the suture is placed in the nasal exten- 
sion of the capsule of Tenon or plica semi-lunaris which is 
attached to this portion of the capsule. 
2. “ Manual of Examination of the Eyes,” Landolt, p. 49, Ed. 1879. “Traits 
d’Ophthalmologie,” Landolt, and Wecker, Vol. I, p. 915. Bestimmung des Schielens. 
Snellem u. Landolt. Handbuch der Augenheilkunde. Graefe und Saemisch, Vol. 
Ill, p. 235.