PALSY OF THE MUSCLES OF THE GLOTTIS. 55 



Paralysis of the chords is recognizable through the laryngoscope 

 when we find an arrest or hampering of the motions of one or both 

 chords, without finding any mechanical obstacle to account for it. 

 When the glottis-closers alone are affected, nothing remarkable is 

 to be seen so long as the patient is at rest ; if, however, he utters 

 a sound, we see that the two chords do not touch at the median 

 line, but gape more or less widely, showing either an imperfect 

 power of closing the glottis, or else no closure of it at all. When 

 the chords gape to the extent of a line, the voice is extinct ; when 

 the gaping is more moderate, vibrations are still possible, but the 

 voice is hoarse, and speaking becomes laborious. 



Palsy of the glottis-openers (musculi cricothyroides) often co- 

 exists with that of the closers, but the latter sometimes is found 

 alone (Bose). Here, upon attempted phonation, the riina glottidis 

 closes, but the vibration of the chords, which should be plainly 

 visible, especially during utterance of deep notes, is absent, and 

 the patient is absolutely voiceless. Palsy of these muscles alone is 

 quite conceivable when one calls to mind that they derive their 

 nerves from a source differing from that of the other muscles (ner- 

 vus laryngeus superior). 



Tttrck distinguishes several forms of paralysis of the glottis- 

 closers. Sometimes the opening of the palsied glottis does not 

 show the usual form of an equilateral triangle with its apex point- 

 ing forward, but instead the gaping is confined sometimes solely to 

 the cartilaginous glottis, sometimes solely to the ligamentous glot- 

 tis, which seems to be due to the fact that in the one case the trans- 

 verse and oblique arytenoid muscles alone are implicated, and in the 

 other only the lateral crico-arytenoid muscles. When the glottis- 

 openers alone are affected, the voice is not changed, but in the mir- 

 ror we can perceive that upon deep inspiration the chord, with the 

 corresponding cartilage of one or of both sides, does not move out- 

 ward, but stops near the middle line. Such cases are generally 

 symptomatic of pressure upon one of the recurrent nerves, so that 

 the palsy is apt to be unilateral, and the closers are usually implicated 

 as well as the openers ; but, as the chord on the other side con- 

 tinues to keep up its normal motions, the voice, though enfeebled and 

 hoarse, is not extinguished. When the patient rests respiration is 

 unimpeded, and only becomes difficult when he makes exertion. In 

 the rare instances where both recurrents are simultaneously com- 

 pressed, both chords lie immovable close to the median line. Breath- 

 ing then becomes very laborious, and the voice is totally extinct. 



It would seem that, besides palsy of the true vocal chords, there 

 is also a palsy of the false chords. Czermak has discovered that 



