CLINICAL SYNDROMES 321 



its fellow but before it does so an apparent divergent strabismus is mo- 

 mentarily manifest." The object should be held three to four feet from 

 the patient to avoid too great an effort at convergence. In other words, the 

 author states it must be held much beyond the point usually necessary in 

 testing for Moebius' sign. This lack of complementary lateral rotation 

 is also more marked the greater the exophthalmos. The divergence of 

 the eyes is a more or less jerky one. Care must be taken to exclude 

 esophoria or exophoria and the possible presence of a paresis of the lateral 

 rectus muscles. The author found the sign as frequent as the von Graefe 

 and Moebius signs but gives no figures as to its frequency nor are there 

 as yet any available in the literature. 



Pathogenesis of the Major Ocular Signs. Heinrich Mueller in 1859 

 gave a brief description of three groups of plain muscle fibers, one 

 bridging over the infra-orbital fissure and one in each eyelid extending 

 vertically from the fornices of the conjunctive to the superior and in- 

 ferior tarsal plates respectively. Merkel and Kallius have failed to con- 

 firm Sappey's rather indefinite description of two bands of plain muscle 

 lying one on either side of the eyeball and termed by him "internal and 

 external orbital muscles." It has been suggested in the past that a spastic 

 condition of Mueller's three muscle bundles, with or without weakness of 

 the orbicularis muscle, was responsible for the ocular phenomena in 

 Graves' disease. Their obvious inability, both from their size and posi- 

 tion, to produce the exophthalmos, as well as the inadequacy of the 

 older theories, such as a widening of the retrobulbar veins from a 

 vasomotor paralysis, as suggested by Sattler and Buschan, chronic passive 

 congestion and edema, and an increase in the amount of the retro-orbital 

 fat (Murray) led to further investigation. The experiments of Benard 

 in 1882 showed that by irritation of the cervical sympathetic, the eyeball 

 is pressed forward and to a certain degree, the closure of the eyelids is 

 prevented. Wiener (1868) showed that irritation of the cervical sympa- 

 thetic ganglion caused increased intra-ocular tension, whilst its destruc- 

 tion caused a lower tension for a time. In 1904 MacCallum and Cornell, 

 having removed the roof of the orbit and the orbital fat in dogs, electrically 

 stimulated the cervical sympathetic and noted peristaltic waves passing 

 backward throughout the tissue surrounding the eyeball and eventually 

 great exophthalmos. By careful dissection and histological examination 

 they demonstrated the presence of plain muscle fibers forming a smooth 

 conical mantle about the eye, continuous anteriorly with the muscle of the 

 lids and forming abundant attachments about the orbital margin and 

 passing backward, thence to end about the foramen, through which the 

 optic nerve enters the orbit. Landstroem, in his inaugural dissertation 

 of 1907 (which has been carefully reviewed in German and American 

 literature), reports the demonstration of a well developed cylinder of 

 plain muscle arising from the septum orbitale, anteriorly, and inserted 



