PALPEBRAL APERTURE with SPECIAL REFERENCE to the SURGICAL CORRECTION of PSEUDOPTOSIS by Rudolf Aebli, M.D.*

Home , Palpebral fissure

THE RELATIONSHIP OF PSEUDOPTOSIS TO MUSCLE TROPIAS AND THE PALPEBRAL APERTURE WITH SPECIAL REFERENCE TO THE SURGICAL CORRECTION OF PSEUDOPTOSIS BY Rudolf Aebli, M.D.*

BERKE'S (1) DISSERTATION on blepharoptosis in 1945 and Spaeth's (2) on the same subject in 1946 were both so complete and so admirable in all respects that there would be no justification at this time for a duplication of their contributions. On the other hand, with the exception of Kirby's (3) paper, in 1940, on ptosis associated with loss of elevation of the eyeball, relatively little has been written on the subject of pseudoptosis caused by vertical muscle tropias. Almost nothing, furthermore, has been written on the relationship of the palpebral aperture to these anomalies. This contribution has a threefold purpose: (1) to explain this relationship; (2) to outline the correct diagnostic procedure in ptosis of the eyelid which results from anomalies of this kind; and (3) to set forth the best methods of treatment for them. ANATOMIC CONSIDERATIONS Before it is possible to discuss intelligently the clinical aspects of muscle tropias and the relationship of the palpebral aperture to them, certain important (albeit elementary) anatomic considerations must be briefly summarized. When the eyelids are in their normal relationship to the eyeball, the margin of the upper lid lies midway between the limbus and the pupillary margin of the iris, while the margin of the lower lid is at the limbus. When the eyes are opened normally, the lids are separated from each other by an elliptical space, the palpebral From the Department of Ophthalmology, New York University Post Graduate Medical School, and the University and Lenox Hill Hospitals, New York City. 336 Rudolf Aebli fissure (aperture). This space measures, on the average, 27 mm. in the horizontal, and 9 mm. in the vertical, aspect. When the eyes are in the primary position, that is, when the gaze is directed straight forward, the relationship of the eyelids to the structures of the eyeball is scrupulously maintained as it has just been described. Similarly, the relationship which has been described is for the most part maintained when the gaze is directed up or down. Jameson (4), who places great emphasis upon this relationship, terms the harmonious interaction of the levator

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A B C FIGURE 1. CONGENITAL PARALYSIS OF BOTH ELEVATORS OF LEFT EYE, WITH PSEUDOPTOSIS AND ALTERNATE FIXATION OF EYES A: When sound right eye fixes, left hypotropia is apparent, with marked ptosis of eyelid. B: When paretic left eye fixes, right eye is higher, sclera shows below at limbus, and cosmetic deformity is more pronounced. C: When both eyes are directed upward, paralysis of elevation of left eye is apparent, with secondary deviation of right inferior obllque. D-E: Postoperative result following operations on eyes consist- ing of resection of left superior rectus, with advancement to limbus, and recession (io mm.) of right inferior oblique by White technique. D: When right eye fixes, moderate left hypotropia is evident but ptosis of lid is slight; compare with A. E: When left eye fixes, upshoot of right eye is seen to have been corrected and sclera is no longer visible at limbus; compare with B. F: WAhen both eyes are directed to left, secondary deviation of right inferior oblique formerly present is no longer seen; compare with C. In this case the operative procedure will be completed by recession of the right superior rectus for 2-3 mm. Since the inferior oblique of this eye has been greatly weakened, special care will be taken at operation not to weaken the superior rectus excessively, there being grave danger under these circumstances of crippling the elevating power of the right eye. Relationship of Pseudoptosis to Muscle Tropias 337 muscles of the eyelid with the elevators and depressors of the eyeball a striking phenomenon of perfect ocular adjustment.

PATHOLOGIC PHYSIOLOGY In cases of disturbed ocular motility associated with hypotropia (a strabismus in which the axis of one eye deviates downward) or hypertropia (a strabismus in which the axis of one eye deviates upward), the lid normally follows the eye downward or upward, with the result that there is either a narrowing or a widening of the vertical dimension of the palpebral fissure (Fig. i). The picture

D E F then presented, as White (5) has stressed, depends upon which eye fixates. If the sound eye fixes, the fellow eye is lower, the lid follows the hypotropic eye downward (6), and the patient presents a picture of marked ptosis (Fig. iA). If, on the other hand, the paretic eye fixes, then the sound eye is higher, the lid follows the hypertropic eye upward, the palpebral aperture is widened, sclera is visible below at the limbus, and the cosmetic deformity is usually more marked (Fig. iB) than when the sound eye fixes It is well to remember in this connection, as Duane (7) has pointed out, that the deviating eye is not necessarily the paretic eye.

CLASSIFICATION AND ETIOLOGY Ptosis of the eyelids (blepharoptosis) falls into two chief catego ries, true ptosis and pseudoptosis. True ptosis is caused by paralysis 338 Rudolf Aebli

A B c FIGURE 2. ACQUIRED PTOSIS CAUSED BY MYASTHENIA GRAVIS A: Complete right-sided ptosis, forcing the patient to fix with the left (and poorer) eye. B: Condition of eyes 15 minutes after injection of prostigmine (gr. 1/40) and atropine sulfate (gr. 1/150). The patient can now open the (better) right eye and fix with it. The left eye is in a position of hypertropia, with widening of the palpebral fissure. C: Condition of eyes 30 minutes after prostigmine-atropine sulfate injection. In this case the ptosis and muscle imbalance were not apparent when the patient was well rested. When he was fatigued, the right lid drooped and closed. The degree of ptosis and tropia varied at different examinations and the measurements were not constant.

A B c FIGURE 3. ACQUIRED PARTIAL PARALYSIS OF LEFT THIRD NERVE, WITH LEFT EXOTROPIA, LEFT HYPOTROPIA, AND PSEUDOPTOSIS The drooping lid and diverging left eye were first noticed 4 years ago, after an un- diagnosed febrile illness, the history of which suggested polioencephalitis. A: When patient fixes with right eye (her usual practice), left exotropia and left hypotropia and ptosis are evident. B: When she fixes with paretic left eye, secondary deviation of right external rectus is apparent. C: When eyes are directed upward and to left, weakness of superior rectus and secondary deviation of right inferior oblique are observed. Marked improvement followed recession of the secondarily contracted left inferior rectus and left external rectus, combined with resection of the paretic left superior rectus. of the levator muscle of the eyelid. A vertical muscle tropia is one of the frequent causes of pseudoptosis. Pseudoptosis and true ptosis may be either congenital or acquired. The congenital variety, which is frequently bilateral and which may be hereditary, may originate in an insertional, a structural, or an innervational, defect of a muscle or a group of muscles (8,9). Some cases are caused by birth trauma, the resultant local or central hemorrhages being followed, in their turn, by muscle fibrosis or atrophy. A B C

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FIGURE 4. ACQUTIRED LEFT PARTIAL PARALYSIS OF THIRD NERVE IN 16-YEAR- OLD PATIENT, FOLLOWING POLIOENCEPHALITIS 10 YEARS EARLIER A: Fixation of left eye in upper temporal quadrant, as result of extreme secondary contractures of left external recttus and left superior rectus. Left lid follows hypertropic eye upward. Palpcbral fissure is markedly widenedl and sclera is visible below at limbus. B: WVhen gaze is directed straight ahead, left eye is immobile and fixed in upper temporal qtuadIrant. C: XVhen eyes are directed to right, left eye is fixed in upper temporal quiadrant. D-F: Postoperative result following operation on all four left recti muiscles tin(er local analgesia at single sitting. The left external rectus, wllich was tense, tauit, an(l secon(larily contracted, was recesse(l to the equator. The left superior recttus, the con(lition of which was similar, was recessed 5 mm. The left internal recttus, wlhich was flabby an(l atrophic, was resecte(l 8 mm. and advanced to the limbus. The left inferior rectus, the condition of which was similar, was also resected 8 mm. D: Postoperative appearance with eyes directed to left; compare with A. E: Postoperative appearance with eyes directed straight ahead; compare with B. F: P'ostoperative appearance with eyes (lirected to right; compare with C. In this case, as in all instances of partial third nerve paralysis, the position of the globe and of the lid varicd. In all stuch cases the position (lepends upon the extent and degree of nerve involvement and upon the amount of secondlary contracture which develops. These illutstrations should be compare(l with figure 3. In that case the left superior rectuis was more markedly paretic and the left inferior rectus (the direct antagonist) hda(ldeveloped a secondary contractuire with the passage of time, with resuiltant left hypotropia, psetidoptosis and narrowing of the fissure. In this case over a period of io years, the left external recttus and left superior rectus had developed a marked secon(ldary contracture, with widening of the palpebral fissure and disfiguring left hypertropia, the sclera being visible at the lower limbus.

A B C

FIGURE 5. UNILATERAL RETRACTION SYNDRO-ME, WITH LEFT PSEUDOPTOSIS CAUSED BY SPASMODI)C CONTRACTION OF ORBICUT,ARIS MUSCLE A: WVhen patient fixes with right eye, left palpebral fissure is narrowed, globe on this side is retracted, and spasm-tiodic contraction of left orbictilaris is evident. B: When eyes are (lirecte(l to left, there is limitation of abdtuction, left palpel)ral fissure is widened, and orbicularis spasmn is relaxed. C: When eyes are directed to right, orbicularis spasm is increased, left palpebral fissuire is even more narrowed than in A, enophthalmos is increased, and there is upshoot of the left eye. A B C

FIGURE 6. CONGENITAL PARALYSIS OF BOTH ELEVATORS OF LEFT EYE, W'ITH TRUE I'TOSIS, PSEUDOPTOSIS, AND JAW-W'INKING REFLEX A: 'When patient fixes with riglht eye, left ptosis is evi(lent. B: A'hen right eye is occlu(ded, left palpelral fissture is smaller in vertical liimlension and trule ptosis is evident. C: When both eves are directed upward an(d to left, weakness of elevation is evident in left eye. Lid is elevated ly tutilization of left occipitofrontalis mtlscle. D: When eyes are (lirected downward, both palpebral fissuires are of equlal size and eyes are on same horizontal level. E: Jaw-wvinking reflex. Left ptosis is evident as jaw is move(l. F-I: Samel)patient (6 years later and 5 years after sturgical correction of paralysis. At the first operation the left superior recttus was resecteci an(d advanced to the limbhts anti a tuck was taklen in the left inferior oblique. At the second operation the left levator, whliclh, thouighi paretic, still possessed somiie power, 1%as resectedi by the Eversbtusch techniquie. F: Patient looks straight ahead; compare with A. G: WVhen eyes are directed tupward, increased power of elevation of left eye is evident, with better raising of lid; compare with C. H-I: Eye is opened with contralateral jaw movements and closedl with ipsilateral jaw movements. In this case, the movements of the left eyelid which occturred when the jaw was moved are probably to be explained by aberrant central nerve connections between the motor branches of the third and fifth nerves. Relationship of Pseudoptosis to Muscle Tropias 341 F G

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The acquired variety also originates in a number of widely different conditions, including meningitis, cerebral injury, thy- roid disturbances, generalized and localized ocular myopathies (Fig. 2), syphilis, polioencephalitis (Fig. 3), and progressive neuri- tides (Fig. 4). Some cases of pseudoptosis originate in spasmodic contraction of the orbicularis muscle (Fig. 5). Quite out of the ordinary is the case reported by Berens and Fonda (io), in which general anesthesia given for the removal of a pilonidal cyst was followed by paralysis of the superior rectus muscle and ps'eudo- ptosis. The cases of orbital myositis described by Dunnington and Berke (i i), in which the eye was fixed in the lower field and was 342 Rudolf Aebli adherent to the floor of the orbit, would also properly be described as instances of pseudoptosis. Whatever may be the underlying cause of the anomaly, the end result is the same: there ensues a disturbance of ocular motility, with hypotropia or hypertropia, which is combined with true ptosis of the eyelids, or pseudoptosis, or both (Fig. 6). When pseudoptosis occurs, however, it is usually most marked in the field in which the hypotropia is greatest (12).

DIAGNOSTIC CONSIDERATIONS If the margin of the upper eyelid droops below its normal position, that is, if it is lower than midway between the limbus and the pupillary margin of the iris, ptosis of some sort can be suspected to exist. The suspicion is verified by the following measurements of the palpebral aperture, which should be an essential part of all ophthalmologic examinations, though they are frequently omitted even by otherwise careful ophthalmologists: 1. The vertical measurement. Any vertical measurement of less than 9 mm. justifies the diagnosis of ptosis of the eyelids if other pathologic processes which might be responsible for a diminution in the normal measurement can be excluded. This measurement is most easily taken while the patient fixes on a small spot on a card held 15 inches from the eye, while first one eye and then the other is occluded (Fig. 7). 2. The horizontal measurement. Whenever this measurement is less than 27 mm., the performance of canthoplasty to aid in the uplift of the lid must be considered. 3. The distance between the margin of the upper lid and the arch of the eyebrow. In the young, normal subject, with the eyes in the primary position, this measurement varies from 15 mm. to i8 mm. In congenital ptosis it may be as much as 25 mm. or even 30 mm. 4. Measurements of the vertical width of the palpebral aperture in the six cardinal positions of gaze. The patient looks up and to the right, up and to the left, to the right, to the left, down and to Relationship of Pseudoptosis to Muscle Tropias 343 the right, and down and to the left. These measurements indicate in which direction of gaze the size of the palpebral aperture is narrowest and also indicate in which of the six cardinal positions the ptosis is greatest. If the measurements indicate that the changes

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A B C D FIGURE 7. CONGENITAL PARALYSIS OF BOTH ELEVATORS OF LEFT EYE WITH HEAD TILT AND PSEUDOPT'OSIS A: Marked ptosis of left upper eyelid. Right eye fixes, left is lower. B: With right eye occluded, left fixes. Left palpebral fissure now has same vertical dimension as right palpebral fissure in A. C: When eyes are directed upward and to right, paralysis of left inferior oblique becomes apparent. D: When eyes are directed upward and to left, paralysis of left superior rectus becomes apparent, together with secondary deviation of right inferior oblique. Operation in this case consisted of resection and advancement to limbus of left superior rectus; advancement of left inferior oblique over orbital margin by Wheeler technique; and recession of right inferior oblique by White technique. The ptosis of the eyelid was corrected by these procedures and the cosmetic result was very satis- factory. are apparently permanent and that the deviation is constant (Fig. 8), operative interference is usually fully justified. One or two considerations are of special importance before operation is undertaken. The first is the determination of the power of the levator muscle, which functions as the normal elevator of the eyelid. When true ptosis exists, this muscle is always paralyzed. It is a simple matter to determine its status by exerting firm pressure on the brow over the supraorbital ridge while the patient endeavors to open his eyes (Fig. 9). The ability to open the eye during this maneuver indicates that the levator muscle is functioning adequately. The presence of a crease or a fold in the upper eyelid during this maneuver also justifies the assumption 344 Ruidolf Aebli of the attachment of an active levator muscle to the skin and tarsus (3). O'Connor (13) has outlined a simple and usefuil teclhniqlue to demonstrate wvhetlher or not tendon contracture lhas occurred. The eye is anestlhetized and the tendon stuspected of contracture is grasped tlhrough the conjunctiva wvith a fixation forceps. Traction is then exerted by this means whlile the patient directs hiis gaze in a direction awvay from that of the maximtum action of the muscle to be tested, innervational relaxation of wvhich is thus secured.

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A B FIGURE 8. CONGENITAL PARALYSIS 01 LEFT SUPERIOR RECTUS WIVITH CON- TRAC7L URE OF LEFT INFERIOR RFCTUS AND PSEUDOPTOSIS A: lWhen patient fixes with right eye, left hypotropia and left ptosis are evident as lid follows downward course of lower eye. B: WVlhen right eye is occluded, patient fixes with left eye and pseudoptosis is no longer apparent. Note good levator action. C: When eyes are directed upward and to left and patient fixes with left eye, paresis of left superior rectus is evident, with secondary deviation of right inferior oblique. D: WVhen eyes are directed upward and to right, good elevator action of left inferior oblique is evident. In this case preoperative measurements taken with cover test showved marked in- trease of left hypotropia in both upper and lower left temporal ficlds, the findings indicating paralysis of the left superior rectus and secondary contracttire of the left inferior rectuts, which was the direct antagonist. The right eye was the fixing eye. Operation consisted of resection, with advancemcnt to the limbus, of the left superior rectus and a 4 mm. recession of the left inferior recttis. By mcans of thcse procedures both eyes were placed on the same horizonital level and pseudoptosis was eliminated. Relationship of Pseudoptosis to Muscle Tropias 345 Contracture is assumed to be present (1) if undue resistance is felt during this maneuver, or (2) if the eye cannot be rotated to either the inner or the outer canthus. The development of contracture warrants the categoric statement that paresis is permanent and furnishes sufficient indication for immediate corrective surgery. The etiologic classification of ptosis of the eyelids is not always possible, even after a careful history, a complete examination, and the performance of all available laboratory tests. An attempt to establish the etiology of the anomaly should, however, be a part of the diagnostic procedure. Whenever it can be determined, the underlying cause should be treated and eliminated before ophthalmic surgery is instituted.

C D

SURGICAL PROCEDURES There is not complete agreement concerning the time at which operation should be undertaken for the correction of ptosis of the eyelids caused by an oculorotary muscle defect. The policy of waiting a minimum of a year following the onset of the paralysis is rather general. I share the opinion of O'Connor (I3) and of Scobee (14) that this is not a wise practice. As both of these observers point out, surgery should be resorted to before contractures develop in either the antagonist or the yoke muscle, a matter which is determined not by the passage of a specific period of time A B C

D E F

FIGURE 9. CONGENITAL, PARALYSIS OF BOTH ELEV'ATORS OF LEFT EYE, WVITH TRUE PTOSIS OF EY'ELID A-B: Appearance of eye when patient was first seen, aftcr two previous operations elsewherc. At the first operation the left superior recttzs hald been resected and the left inferior obliqtue advanced. At the second, the left levator palpebraruni had l)een resected by the EversbuscII technique. Since the levator muscle in this case was markedly paretic, it can fairly be said that the second olperation was ill-chosen. B: Trtie ptosis of left eyeli(d due to levator paralysis. C: Wkhen eyes are directed upward, elevation of left eyelid is caused by action of left occipitofrontalis. Note position of left brow. D: Condition of eye after Machek operation on left tipper eyelid; compare with B. E: WVhen gaze is directed upwvard, left lid is raised because of adhesions between lid and occipitofrontalis produced by Machek operation; compare with C. F: WVhen the gaze is (lirected downward, the left palpel)ral fissure is wider than the right becatise the fixed left upper eyelid does not follow the globe (lowvnward as well as the right tipper eyelid follows the fellow globe. Operations which prodtice intimate adlhesions between the lid and the occipitofrontalis are ustially more sticcessful than other proce(ltlres wvlhen the levator is weak and the superior rectus fibrotic. The condition shown in F, however, is usually present when this operation is done. Relationship of Pseudoptosis to Muscle Tropias 347 but by careful clinical observation at weekly intervals. Contrac- tures sometimes occur within a week after the onset of the paralysis, though this is not usual. More often io to 12 weeks elapse before they become evident. Furthermore, spontaneous improvement almost never occurs. It is the exception rather than the rule to find any regression in the condition with the passage of time (Figs- 3,4,10). The objective of surgery in pseudoptosis resulting from muscular tropias is to place both eyes on the same horizontal plane. When this has been accomplished, any residual true ptosis can be. corrected by the Blaskovicz or the Eversbusch operation, though these procedures are useful only if levator action is present. Since the fixing eye is of paramount importance in the selection of the proper surgical approach, the following principles are basic (1,15): 1. In patients who fix with the paretic eye (Fig. 1), the sound eye is higher, as has been pointed out, the vertical dimension of the palpebral aperture is greater, the sclera is visible below at the limbus, and the cosmetic deformity is more prominent. In such cases the operation of choice is recession of the superior rectus and the inferior oblique muscles of the higher (that is, the sound) eye. If, after these procedures have been correctly carried out, hypertropia is still present in the lower temporal field, paresis of the inferior rectus may be assumed and resection of that muscle should be undertaken. 2. In patients who fix with the sound eye, the affected eye is lower. The operation of choice in such cases is resection and advancement of the superior rectus of the paretic eye, as recommended by Berens and Loutfallah (i6), followed by advancement of the inferior oblique over the orbital margin, as recommended by Wheeler (17). In the opinion of Berens and Loutfallah, a shortening operation should be considered when paresis or underaction is present, especially in cases in which pseudoptosis is associated with hypotropia (Fig. 8), in contrast to the weakening procedures indicated in cases characterized by spasm or overaction. These observers emphasize that hypotropia associated with homolateral pseudoptosis should be corrected by resection of the underactin- muscle, not by weakening of the contralateral synergist. A B

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FIGURE 10. FASCIAL ADHESIONS OF GLOBE, WITH FIBROSIS AND SECONDARY CONTRACTURES This 21-year-old patient had had a right orbital hemorrhage in the course of whoop- ing cough at the age of one year. During a paroxysm the eye bulged forward, and over the succeeding years it had gradually diverged upward and become fixed in its present position. Vision in the right eye was 15/2oo and in the left 20/20. The fundi were normal and roentgenograms of the right orbit were negative. A: Right eye is fixed in upper field, palpebral fissure is widened, globe appears proptosed, and sclera is visible for 7 mm. below at limbus. B: When right eye is directed downward, globe does not descend to horizontal plane. C: When eyes are directed downward and to right, right globe lags and paresis of right inferior rectus is apparent. D: When eyes are directed downward and to left, paresis of right superior oblique is apparent. E: Appearance of patient after eyes had been placed on same horizontal plane. Note appearance of palpebral fissure here as compared with A. At operation the superior rectus was found taut and fibrous. The intermuscular fascia was thickened and adherent to the roof of the orbit. Operation consisted of severance of the adherent facial bands and recession of the fibrotic superior rectus to the equator of the globe. Relationslip of Pseuidoptosis to Mucscle Tropias 349 MIy owvn experience is to the effect that the greater part of the increased elevation obtained in patients who fix with the sotind eye and whose fellowv eye is lowver (Fig. 6) is accomplislhed by resection and advancement of the superior rectus, very little of the desired effect being obtained from advancement of the inferior oblique. If careful preoperative measurements have slhowvn no increase in hypotropia in the lowver fields, so that it may be assumed that no contracture of the direct antagonist has occturred, recession of the inferior rectus is not advisable. If, however, these measuireilments showv an increase of hypotropia in botlh lowver and tipper teimporal fields, then recession of the ipsilateral inferior recttus is indicated, in addition to resection and advancement of the stuperior rectuis combined wvith advancement of the inferior oblique. WhIiite and Brown (15) lhave stressed these principles, and my owvn experience showvs that, wvlhen they are carefully followved, good results can usually be anticipated. 3. In patients whlio fix alternately wvitlh the souind and the paretic eye, operation on botlh eyes is indicated. Bilateral operation is a sound surgical principle to followv in most instances of alternating tropias, and there is no doubt of the wvisdom of its application to alternating vertical deviations (Fig. i). The operation of choice is recession of the superior rectus of the hiiglher eye combined withl resection and advancement to thie limbus of the superior rectuis of the lowver eye. If these procedures are not suiccessful in placing the two eyes on the same horizontal plane, a recession of the inferior oblique muscle of the higlher eye nmay also be necessary, combined with tenectomy of the superior obliqlue of the lowver eye. It is Berke's opinion (i8) that the latter operation slhould be performed wvhienever the mtuscle is overactive and symptoms caused by lhypertropia cannot be relieved by nonsturgical methods. Depending upon the circtumstances of the individual case, it mnay be combined wvitlh resection, advancement, or ttucking of the inferior oblique of the ipsilateral eye. It inay also be combined with shortening operations on the contralateral inferior recttus. WVhen paralysis of elevation is present and the stuperior rectuis and inferior oblique are weak, tenotomy on the ipsilateral stuperior oblique will increase the relative lifting powver of the inferior oblique. In Berke's opinion it is a simple matter, wvlhen one is resecting the 350 Ru-dolf Aebli superior rectus for relief of paralysis of elevation, to excise a portion of the tendon of the superior oblique under the superior rectus. Tenotomy is carried out on the portion of the tendon nasal to the superior rectus and is combined with excision of 5-7 mm. of the tendon. The amount excised depends upon the amount of deviation to be corrected. Simple tenotomy will correct only 5-10 prism diopters, which is not sufficient; the average correction necessary is about 21 prism diopters. Residual true ptosis present after correction of the actual muscle tropia should be corrected, in order of choice, by (i) resection of the levator muscle, (2) the Motais operation or some allied procedure, or (3) the production of intimate adhesions between the lid and the occipitofrontalis muscle. My own preference in cases in which the levator muscle is paralyzed and the superior rectus muscle is fibrotic is for an operation which utilizes the occipitofrontalis muscle (Fig. 9). Some such procedure is, in fact, essential under these circumstances, since, when the superior rectus muscle is weak or fibrotic, the Motais operation is inadequate, as are all operations based on the same principle. When underaction of a vertical muscle is associated with ptosis caused by a depressed position of the eyeball, such as may occur in postoperative paresis of the inferior oblique, the ptosis, as Berens and Loutfallah (16) point out, cannot be corrected by weakening the action of the spastic muscle. Instead, it is necessary to employ some operation which will elevate the depressed eyeball and which will secondarily elevate the eyelid. Since underaction of a muscle is usually accompanied by spasm of the synergist of the other eye, it is desirable, in many cases, to attempt to weaken the action of the overacting muscle. Myotomy or retrodisplacement of the spastic inferior oblique of one eye may be performed for paresis or paralysis of the superior rectus of the other eye, though, as has just been pointed out, neither procedure will correct an associated ptosis. In cases of pseudoptosis with narrowing of the palpebral aperture resulting from orbicularis spasm, it is best to refrain from operation (Fig. 1 i). In retraction syndromes with enophthalmos and orbicularis spasm, resection of the fibrous externi to correct the esotropia Relationship of Pseudoptosis to Muscle Tropias 351 will increase the enophthalmos and will make a bad matter worse. The pseudoptosis will remain unaffected. In the presence of a good near point of convergence, moderate recession of the interni will improve the esotropia but will have no effect on the orbicularis spasm or on the pseudoptosis.

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FIGURE 11. BILATERAL RETRACTION SYNDROME WITH PSEUDOPTOSIS A: When patient fixes with right eye, left palpebral fissure is narrowed, there is some retraction of left globe, and spasm of left orbicularis is evident. B: When patient fixes with left eye, right palpebral fissure is narrowed, there is some retraction of right globe, and spasm of right orbicularis is evident. C: Limitation of abduction when eyes are directed to right, with widening of right palpebral fissure. D: Loss of abduction when eyes are directed to left, with widening of left palpebral fissure.

SUMMARY AND CONCLUSIONS 1. Ophthalmic literature contains surprisingly little on the subject of pseudoptosis caused by vertical muscle tropias and even less on the relationship of the palpebral aperture to these anomalies. 2. The width of the palpebral aperture varies with the status of muscle balance. In instances of hypotropia the eyelid follows the eye downward, with resulting pseudoptosis. In instances of hypertropia, on the other hand, the eyelid follows the eye upward, with a resulting widening of the fissure, so that the sclera is visible below at the limbus. 3. The fixing eye determines the width of the palpebral aperture. The greater the hypotropia or hypertropia, the greater will be the variations in the vertical dimension of the aperture. The aperture 352 Rudolf Aebli is narrovest, and pseudoptosis is most pronounced, in the field in wlhiclh hiypotropia is greatest. 4. The results of sturgery in instances of vertical muscle tropias combined wvitlh pseudoptosis vill be greatly improved if certain general principles are strictly observed: a) Thie objective of surgery in pseudoptosis caused by muscle tropias should be to place botlh eyes on the same horizontal plane. Whatever residuial true ptosis remains after the accomplishment of this objective can be corrected later. b) The fixing eye is of paramount importance in the selection of the proper surgical approaclh. c) The surgical attack should be limited to the mtuscles acting in the fields in wvliclh the deviation is greatest. Muscles acting in fields which are relatively normal should be left undisturbed.

REFERENCES

1. Berkc, R. N.: Blepharoptosis, `Arch. Ophth., 34: 434-450, 1945. 2. Spaeth, E. B.: Bleplharoptosis-congenital an(I acqtlired, Tr. Am. Acad. Ophth., 5r 1,17-162, 1q46. 3. Kirby, D. B.: Blepharoptosis-the techniquie of its suri-gical correction, Surg., Gynec. &; Obst.. .138-1-9 19,10). 4. Jameson, 1P. C.: Suirgical management of ptosis with special reference to use of suiperior recttis nmuiscle, Arclh. Ophlthl., j8: 54i7-557, 1937. 5. White, J. W.: The choice of the fixating eye in paralytic an(1 non-paralytic stralbismitls, Tr. Amii. OPhtht. Soc., 41: 319-324, 1913. 6. Wagmnan, 0. H.: Resection of inferior ol)li(que muscle in hypotropia, Am. J. Oph1thl., 28: 1226-123(i, 915- 7. Dtuane, A.: Anomalies of ocuilar mutscles, symptoms and (liagnosis, evidences of paralysis and spasm, Arch. Ophth ., I]: 394-4j22, 19341. 8. Duiane, A.: Diagniosis in motor anomvialies of the eye, Arch. Ophtll., 48: 1-18, 1919. 9. BielsclhoNwsky, A.: Lectuires on motor anomalies, stLipra-nrtclear paralysis, Am. J. Opllthl., 22: 603-613. 1939. io. Bcrens, C., and Fon(la, G.: Ocuilar se(luelae of a(dministration of general anes- tlhesia, Arch. Ophth ., 33: 385-388, 1945. ii. Dtnniington, J. H., an(d Berke, R. N.: Exophtlmailnius due to chronic orbital myositis, Arch. Ophth ., 3: 4.16-166, 1943. 12. Dtiane, A.: Cite(d by 1\arlow, S. B.: Isolated paralysis of inferior oblique, Arch. OPh1th., 52: 12-24, 1923. 13. O'Connor, R.: Contractuire in ocular muscle paralysis, Am. J. Ophth., 26: 69-71, 1943. 14. Scobec, R. G.: The Octulorotary Mutiscles, St. Loujis, The C. V. Mosby Company, 1947. 15. AW'hite, J. WV., an(l Brown2,H. WV.: Occurrence of vertical anomalies associated with convergent anid (livergent anomialies, Arch. Ophth., 31: 999-1009, 1939. i6. Berens, C., and I outfallah, M.: Resection of the left inferior oblique muscle at its Relationship of Pseudoptosis to Muscle Tropias 353 scleral attachment for postoperative left hypotropia and pseudoptosis, Am. J. Ophth., 26: 528-533, 1943. 17. Wheeler, M. J.: Advancement of the superior oblique and inferior oblique ocular muscles, Collected Papers of John M. Wheeler, New York, Columbia University Press, 1939. i8. Berke, R. N.: Tenotomy of the superior oblique muscle for hypertropia, Arch. Ophth., 38: 605-644, 1947. 19. Aebli, Rudolf: Retraction syndrome, Arch. Ophth., io: 602-610, 1933. 20. Anderson, J. R.: Ocular vertical deviations, Brit. J. Ophth., Monograph Supp. XII, August, 1947. 21. Bramwell, E.: The upward movement of the eyes, Brain, 51: 1-17, 1928. 22. Collier, J.: Nuclear ophthalmoplegia with especial reference to retraction of the lids and ptosis and to lesions of the posterior commisure, Brain, 50: 488-498, Oc- tober, 1927. 23. Gifford, S. R.: The Machek operation for ptosis, Arch. Ophth., 8: 495-502, 1932. 24. Meek, R. E.: Applied anatomy of the eye; relation to ophthalmic surgery, Arch. Ophth., 26: 494-513, 1941- 25. Moffett, R. D., Aebli, R., and Smith, C. H.: Recent epidemic of poliomyelitis in New York City, Ann. Clin. Med., 2: 427-439, 1924. 26. Morton, H. M.: Treatment of ptosis, Eye, Ear, Nose & Throat Month., 8: 155-158, 1929. 27. Ruedemann, A. D.: Surgical treatment of ptosis of the eyelid, S. Clin. North America, 17: 1503-1509, 1937. 28. Smith, H. C.: Imbalance of the vertically acting extra-ocular muscles, Arch. Ophth., 4: 533-544, 1930- 29. Walsh, F. B.: Myasthenia Gravis and its ocular signs: a review, Tr. Am. Ophth. Soc., 51: 556-622, 1943. 30. White, J. W.: Surgery of the inferior oblique at or near the insertion, Am. J. Ophth., 26: 586-591, 1943. 31. Wolff, E.: Relative ptosis, Tr. Ophth. Soc. U. Kingdom, 53: 317-319, 1933.