602 UNILATERAL AND DOUBLE PARALYSIS OF THE FACIAL. 



motor fibres to the stylohyoid and posterior belly of the digastric, occipitalis, all the 

 muscles of the external ear, the muscles of expression, buccinator and platysma. 

 The facial also contains secretory fibres for the face (compare 288). 



Although most of the branches of the facial are under the influence of the will, yet most men 

 cannot voluntarily move the muscles of the nose and ear. 



Anastomoses. The branches of the seventh nerve on the face anastomose with 

 those of the trigeminus, whereby sensory fibres are conveyed to the muscles of 

 expression. The sensory branches of the auricular branch of the vagus, and the 

 great auricular, enter the peripheral ends of the facial, and supply sensibility to the 

 muscles of the ear j while the sensory fibres of the third cervical nerve similarly 

 supply the platysma with sensibility. Section of the facial at the stylomastoid 

 foramen is painful, but it is still more so if the peripheral branches on the face are 

 divided (Recurrent sensibility, 355). 



Pathological. In all cases of paralysis of the facial, the most important point to determine 

 is whether the seat of the affection is in the periphery, in the region of the stylomastoid 

 foramen, or in the course of the long Fallopian canal, or is central (cerebral) in its origin. This 

 point must be determined by an analysis of the symptoms. Paralysis at the stylomastoid 

 foramen is very frequently rheumatic, and probably depends upon an exudation compressing 

 the nerve ; the exudation probably occupying the lymph-space described by Rudinger on the 

 inner side of the Fallopian canal, between the periosteum and the nerve, and which is a 

 continuation of the arachnoid space. Other causes are inflammation of the parotid gland, 

 direct injury, and pressure from the forceps during delivery. In the course of the canal, the 

 causes are fracture of the temporal bone, effusion of the blood into the canal, syphilitic 

 effusions, and caries of the temporal bone ; the last sometimes occurs in inflammation of the 

 ear. Amongst intracranial causes are affections of the membranes of the brain, and of the 

 base of the skull in the region of the nerve, disease of the "facial nucleus"; lastly, affection 

 of the cortical centre of the nerve and its connections with the nucleus. [No nerve is so liable 

 as the seventh to be paralysed independently.] 



Symptoms of Unilateral Paralysis of the Facial [or Bell's Paralysis]. 1. Paralysis of the 

 muscles of expression : The forehead is smooth, without folds, the eyelids remain open 

 (lagophthalmus paralyticus), the outer augle being slightly lower. The anterior surface of the 

 eye rapidly becomes dry, the cornea is dull, as, owing to the paralysis of the orbicularis, the 

 tears are not properly distributed over the conjunctiva, and, in fact, in consequence of the 

 dryness of the eyeball, there may be temporary inflammation (keratitis xerotica). In order 

 to protect the eyeball from the light, the patient turns it upwards under the upper eyelid 

 {Bell), relaxes the levator palpebral, which allows the lid to fall somewhat {Hasse). The nose 

 is immovable, while the naso-labial fold is obliterated. As the nostrils cannot be dilated, the 

 sense of smell is interfered with. The impairment of the sense of smell depends more, 

 however, upon the imperfect conduction of the tears, owing to paralysis of the orbicularis 

 palpebrarum and Horner's muscle, thus causing dryness of the corresponding side of the nasal 

 cavity. Horses, which distend the nostrils widely during respiration, after section of both 

 facial nerves, are said by CI. Bernard to die from interference with the respiration, or at least 

 they suffer from severe dyspnoea (Ellcnbergcr). The face is drawn towards the sound side, so that 

 the nose, mouth, and chin are oblique. Paralysis of the buccinator interferes with the proper 

 formation of the bolus of food ; the food collects between the cheek and the gum, from which it 

 is usually removed by the patient with his fingers ; saliva and fluids. escape from the angle of 

 the mouth. During vigorous expiration, the cheeks are puffed outwards like a sail. The speech, 

 may be affected owing to the difficulty of sounding the labial consonants, (especially in double 

 paralysis), and the vowels, u, ii (ue), b (oe) ; while the speech, in paralysis of the branches to 

 both sides of the palate, becomes nasal ( 628). The acts of whistling, sucking, blowing, and 

 spitting are interfered with. In double paralysis, many of these symptoms are greatly in- 

 tensified, while others, such as the oblique position of the features, disappear. The features 

 are completely relaxed ; there is no mimetic play of the features, the patients Weep and laugh, 

 "as it were, behind a mask" (Romberg). 2. In paralysis of the palate, when the uvula is 

 directed towards the sound side, and the paralysed half of the palate hangs down and cannot be 

 raised (large superficial petrosal nerve), it is not determined to what extent this condition 

 influences the act of deglutition and the formation of the consonants. 3. Taste is interfered 

 with; either it is absent on the anterior two-thirds of the tongue, or the sensation is delayed 

 and altered. This is due to an affection of the chorda. 4. Diminution of saliva on the affected 

 side was first described by Arnold ; still, we must determine to what extent a simultaneous 

 affection of the sense of taste may cause a reflex interference with the secretion of saliva, or 

 whether rapid removal of the saliva through the opened lips and angle of the mouth may cause 

 the dryness on the affected side of the mouth. 5. Roux pointed out that hearing is affected, 



