P A T H O L O G Y A N D S U R G E R Y O F B E L L ' S P A L S Y . A R E P O R T O F 1 0 8 C A S E S S U B J E C T E D T O T H E B A L L A N C E - D U E L O P E R A T I O N
KARSTEN K E T T E L *
T h e term B e l l ' s p a l s y h a s b e e n used i n d i s c r i m i n a t e l y for a l m o s t e v e r y k i n d of p e r i p h e r a l f a c i a l p a l s y , r e g a r d l e s s of its nature. In t h i s p a p e r the term is restricted to cases in w h i c h f a c i a l p a l s y is the o n l y c l i n i c a l s y m p t o m , and in w h i c h it h a s not been p o s s i b l e to demonstrate a l o c a l cause.
T h e a d v a n c e s in u n d e r s t a n d i n g a n d treatment of this disease are especi-a l l y due to B especi-a l l especi-a n c e especi-and D u e l4
, C a w t h o r n e8
, C o l l i e r9
, H i l g e r1 8
a n d Sul-livan 4 1
.
A N A T O M Y
D e s c r i p t i o n s of t h e a n a t o m y of t h e f a c i a l n e r v e t h r o u g h o u t i t s c o u r s e c a n be t o u n d in a n y t e x t b o o k . T h e r e are also t h e e x c e l l e n t p a p e r s b y L a t h r o p 2
3 , S u l -livan a n d S m i t h 42 a n d T s c h i a s s n y 45.
I n Bell's p a l s y t h e f a c i a l n e r v e is a f f e c i e d in i t s i n t r a t e m p o r a l c o u r s e b e t w e e n t h e p o s t e r i o r e n d of t h e l a t e r a l s e m i c i r c u l a r c a n a l a n d t h e s t y l o m a s t o i d f o r a m e n . Certain d e t a i l s of t h e p a t h w a y should be s t r e s s e d .
In i t s p e r i p h e r a l p a r t t h e n e r v e is s u p e r f i c i a l l y s i t u a t e d , b u t in i t s t e m p o r a l course b e c o m e s e n c l o s e d b y t h e rigid F a l l o p i a n c a n a l , c o n n e c t e d w i t h t h e w a l l b y fibrous s t r a n d s r u n n i n g t o t h e n e r v e sheath. W i t h i n t h e s t y l o m a s t o i d f o r a m e n a n d a t i t s exit the n e r v e is c o m p a c t l y b o u n d d o w n a n d i n t i m a t e l y s u r r o u n d e d b y a cíense p e r i o s t e a l s h e a t h , w h i c h l e a v e s i t v e r y little s p a c e t o e x p a n d
A d e s c r i p t i o n of t h e blood s u p p l y is i m p o r t a n t f o r clinical reasons. T h e i n t r a -t y m p a n i c p a r -t of -t h e n e r v e , -t h e m a s -t o i d cells, -t h e s e m i c i r c u l a r c a n a l s a n d -the t y m p a n i c c a v i t y are m a i n l y n o u r i s h e d b y t h e s t y l o m a s t o i d a r t e r y , a b r a n c h of t h e p o s t e r i o r a u r i c u l a r , w h i c h e n t e r s t h e F a l l o p i a n canal a t t h e s t y l o m a s t o i d f o r a m e n a n d runs p r o x i m a l l y . T h e r e a r e t w o p r i n c i p a l a n a s t o m o s e s . A t t h e knee of t h e f a c i a l canal, p o s t e r i o r to the t y m p a n u m , t h e s t y l o m a s t o i d a r t e r y a n a s t o m o s e s w i t h t h e s u p e r i o r p e t r o s a l b r a n c h of t h e m i d d l e m e n i n g e a l , w h i c h e n t e r s t h e canal b y t h e h i a t u s facialis. T h e s e c o n d a n a s t o m o s i s c o n c e r n s t h e p o s t e r i o r t y m p a n i c branch of t h e s t y l o m a s t o i d a r t e r y ; this f o l l o w s t h e chorda t y m p a n i in t h e p o s t e r i o r part of t h e t y m p a n i c c a v i t y a n d on t h e t y m p a n u m b e f o r e j o i n i n g w i t h branches t o the t y m p a n u m f r o m t h e i n t e r n a l m a x i l l a r y , a s c e n d i n g p h a r y n g e a l , m i d d l e m e n i n g e a l a n d c a r o t i d arteries.
R e l a t ó r i o a p r e s e n t a d o a o X I X C o n g r e s s o I n t e r n a c i o n a l d e O t o - N e u r o - O f t a l m o ¬ l o g i a , r e u n i d o e m S ã o P a u l o e m 11-17 d e j u n h o d e 1954, s u b o r d i n a d o a o 2º t e m a o f i c i a l : Fisiopatologia do nervo facial.
Sullivan a n d S m i t h 4 2 have d e s c r i b e d the arterial s u p p l y of n e r v e s on m i c r o s c o p i c a l e x a m i n a t i o n . On r e a c h i n g a n e r v e , t h e n u t r i t i e n t v e s s e l s d i v i d e into a s c e n d -ing and d e s c e n d i n g branches, which c o u r s e in the e p i n e u r i u m . F r o m t h e s e p r i m a r y divisions s e c o n d a r y b r a n c h e s a r e g i v e n off p e n e t r a t i n g m o r e d e e p l y a n d d i v i d i n g f u r t h e r , b e i n g p r e d o m i n a t e l y a r r a n g e d in l o n g i t u d i n a l f a s h i o n in the p e r i n e u r a l or i n t e r f a s c i c u l a r c o n n e c t i v e t i s s u e and f o r m i n g a l o n g i t u d i n a l v a s c u l a r bed. N o one n u t r i e n t a r t e r y m a y be c o n s i d e r e d a s d o m i n a t i n g a n y p o r t i o n of this p l e x u s . B u t t h e facial n e r v e p r e s e n t s a s p e c i a l p r o b l e m , a s H i l g e r p o i n t s o u t : "In the case of e n d - a r t e r i e s w i t h o u t c o l l a t e r a l s , a peripheral c a t a c l y s m m a y o c c u r as, for e x a m p l e , in the inner ear. I n a c o n f i n e d a n a t o m i c s i t u a t i o n w h e r e a s s o c i a t e d e d e m a is able by c o m p r e s s i o n t o p r e v e n t c o l l a t e r a l a r t e r i a l s u p p l y , an a n a l a g o u s c o n d i t i o n is c r e a t e d . E d e m a within the firm f i b r o u s s h e a t h of the f a c i a l n e r v e in the region of the s t y l o m a s t o i d f o r a m e n is an e x a m p l e . "
I t m u s t be r e m e m b e r e d t h a t t h e facial n e r v e , in a d d i t i o n t o s u p p l y i n g the facial m u s c l e s w i t h m o t o r i m p u l s e s , a l s o c a r r i e s s e n s o r y , s e c r e t o r y a n d g u s t a t o r y fibres, as d e s c r i b e d in d e t a i l by T s c h i a s s n y 4 5 . D e t a i l e d c o m m e n t s on this o r g a n i z a -t i o n will be m a d e la-ter.
P A T H O L O G Y
T h e p r i m a r y cause of Bell's p a l s y is an ischaemia of the facial nerve
near the s t y l o m a s t o i d f o r a m e n
3>
8 > 2 2 , 4 1p r o b a b l y caused by arteriolospasm
1 8.
A s a result of this, various structural alterations take p l a c e in the facial
nerve between the lateral semicircular canal and the s t y l o m a s t o i d foramen
and in s o m e cases a l s o in the s u r r o u n d i n g bone. T h e extent of these
alterations d e p e n d s u p o n the severity of the interruption of b l o o d s u p p l y ,
w h i c h m a y be short and transient, or p r o l o n g e d . In the f o l l o w i n g the
p a t h o l o g i c a l a n a t o m y , the p a t h o g e n e s i s and the e t i o l o g y w i l l be surveyed
separately.
Pathological anatomy
O w i n g to the m a r k e d l y benign nature of the disease it was not untill
1 9 3 2 , when B a l l a n c e and D u e l
4p r o p o s e d d e c o m p r e s s i o n of the facial nerve
in cases of B e l l ' s p a l s y , o p e n i n g the F a l l o p i a n canal f r o m the stylomastoid
foramen to the lateral semicircular canal and splitting the nerve sheath,
that an o p p o r t u n i t y was offered to inspect the nerve and its surroundings
in view. By this e x a m i n a t i o n new w a y s were paved for the study of the
disorder. T h e alterations observed in the nerve, in the mastoid c e l l s , and
in the F a l l o p i a n canal shall be described separately.
a ) The facial nerve, in fresh and r e l a p s i n g palsies, b e c o m e s u n d u l y
constricted at the s t y l o m a s t o i d f o r a m e n and e d e m a t o u s p r o x i m a l to this
point. Cawthorne describes h o w , in 4 0 out 4 2 cases, tiny h a e m o r r h a g i c
streaks were seen running l o n g i t u d i n a l l y u p w a r d s within the nerve sheath.
On s p l i t t i n g of the sheath the nerve m a y be seen to bulge like a hernia
through the slit.
p a l s y , w h o died from other and various c a u s e s
1-
1 0>
2 9-
3 0. F r o m these it
appears that the investigators f o u n d p u r e l y degenerative alterations of
axis-c y l i n d e r s and m e d u l l a r y sheaths, most marked in the peripheral parts of
the nerve, w h i l e i n f l a m m a t o r y products have not been demonstrated.
E x c l u d i n g all slight and d u b i o u s alterations, I have in 5 6 out of
1 0 8 cases f o u n d a distinct and often p r o n o u n c e d e d e m a of the nerve,
e s p e c i a l l y in fresh p a l s i e s of a p p r o x i m a t e l y 1-3 m o n t h s duration, and in
r e l a p s i n g p a l s i e s .
In 12 cases a v i o l e n t e d e m a of the nerve was encountered. In 9 of
these the p a l s y had lasted 2 m o n t h s or less, in one 7 a n d in one 9 months.
T h i s indicates that the e d e m a m a y a s s u m e a subchronic character. In 3
cases the nerve was atrophic. In the first the p a l s y h a d o n l y lasted for
three m o n t h s , but it started s u d d e n l y and was a c c o m p a n i e d b y severe p a i n ,
indicating c o m p l e t e vascular o c c l u s i o n f r o m the o n s e t
1 3. In the next the
p a l s y started three years before a d m i s s i o n , and was f o l l o w e d by an
in-c o m p l e t e rein-covery. In the last in-case the patient h a d h a d 3 r e l a p s e s 1 2 ,
10 and 4 y e a r s p r e v i o u s l y , and had recovered very b a d l y .
In a case which is the o n l y o n e p u b l i s h e d of its kind I had an o p
-portunity of m a k i n g a m i c r o s c o p i c e x a m i n a t i o n of the nerve. T h i s patient
was suffering from a Melkersson's s y n d r o m e
2 8: facial p a l s y , angioneurotic
e d e m a of the lips and in s o m e cases a l i n g u a plicata, but everything points
to the fact that the Melkersson p a l s y is a l s o due to an ischaemia of the
facial nerve near the s t y l o m a s t o i d f o r a m e n . It is referred on account of
its unique p o s i t i o n , illustrating an extreme degree of p a t h o l o g i c a l
altera-tion of the nerve a n d its surroundings due to ischaemia, even t h o u g h not
strictly a case of B e l l ' s p a l s y in accordance with the definition given in
this paper.
On J a n u a r y 29 d e c o m p r e s s i o n of t h e l e f t facial n e r v e w a s p e r f o r m e d , t h e f o l l o w i n g o b s e r v a t i o n s b e i n g r e c o r d e d : " T h e s u p e r f i c i a l cells are l a r g e a n d g l o s s y . I n t h e d e p t h a r o u n d t h e a n t r u m a n d in t h e cells b e t w e e n t h e p o s t e r i o r w a l l of t h e a u d i t o r y m e a t u s find t h e sinus t h e bone is s o f t , i n c r e a s i n g l y so t o t h e p a r t a r o u n d t h e s t y l o m a s t o i d f o r a m e n . T h e e n t i r e f a c i a l canal is c o m p l e t e l y n e c r o s e d in i t s d i s t a l half, a n d t h e r e m a i n i n g p a r t is o p e n e d . N e i t h e r k n i f e n o r s c i s s o r s are u s e d , but t h e n e r v e sheath is seen t o be o p e n , a n d f r o m it a highly o e d e m a l o u s piece of t h e n e r v e b u l g e s o u t , b e i n g c o n i c a l l y p o i n t e d d o w n w a r d a n d of a g r a y i s h pink color. T h e p o i n t of t h e n e r v e , h o w e v e r , i s of a m u c h d a r k e r red color than the r e m a i n i n g part. T h e piece o f t h e n e r v e p r o j e c t i n g f r o m t h e o p e n i n g in l h e sheath is 7 m m long. I t is r e s e c t e d a n d e x a m i n e d m i c r o s c o p i c a l l y . A n e r v e t r a n s -p l a n t t a k e n f r o m t h e ilio-inguinal nerve is g r a f t e d " ( a n d t h e m o b i l i t y r e a -p -p e a r e d t e n m o n t h s l a t e r ) .
T h e results of t h e m i c r o s c o p i c e x a m i n a t i o n of the o s s e o u s t i s s u e m a y be out-lined a s f o l l o w s : 1) S u p e r f i c i a l cells s c a n t y , l i m i t e d s u b p e r i o s t e a l g r a n u l a r b o n y d e c a y , bone o t h e r w i s e n o r m a l , w i t h n o s i g n s of n e c r o s i s a n d n o round cell i n f i l t r a -t i o n ; 2 ) P e r i a n -t r a l c e l l s : g r a n u l a r d e c a y e d o s s e o u s -t i s s u e , sligh-t n e c r o s i s here and t h e r e , small t u f f t s of "cicatricially" c h a n g e d c o n n e c t i v e t i s s u e e n c l o s i n g small g r o u p s of g r a n u l a r d e c a y e d bone, n o i n f l a m m a t o r y i n f i l t r a t i o n ; 3 ) T i s s u e from t h e p a r t s near t h e s t y l o m a s t o i d f o r a m e n : s a m e a s u n d e r 2.
T h e m i c r o s c o p i c e x a m i n a t i o n o f t h e n e r v e a n d t h e n e r v e sheath w a s recorded a s f o l l o w s : " T h e n e r v e sheath c o n s i s t s of d e n s e c o l l a g e n i c c o n n e c t i v e tissue very p o o r in cells b u t e n c l o s i n g small v e s s e l s a n d n e r v e branches. I n t h e c o n n e c t i v e t i s s u e a r e s l i g h t "cicatricial" a l t e r a t i o n s a n d a f e w small g r o u p s of c h a l k y d e p o s i t s . T h e lumen of a s m a l l v e n o u s branch c o n t a i n s b u l g i n g , p a r t i a l l y c o n n e c t e d , s l i g h t l y c h a l k y c o n n e c t i v e t i s s u e m a s s e s ( p o s s i b l y a t h r o m b u s in full o r g a n i z a t i o n ) . O t h e r -w i s e t h e c o n n e c t i v e t i s s u e is t h e s e a t of o e d e m a a n d h e m o r r a g h e a n d is c o v e r e d on t h e inside w i t h r e m n a n t s of a f i b r i n o u s e x s u d a t e . N o r e m n a n t s of blood p i g -m e n t a n d n o f r e s h - f o r -m e d t h r o -m b u s a r e seen in t h e vessels. O n t h e w h o l e the n e r v e is of a u n i f o r m , m o d e r a t e l y cellular s t r u c t u r e , still it is s o m e w h a t loose e v e r y w h e r e . T h e n e r v e f i l a m e n t s s t a i n l i g h t l y , t h e y a r e of u n e q u a l size a n d n o t a l w a y s of a r e g u l a r l y circular s h a p e in t r a n s v e r s e s e c t i o n s . T h e n e r v e f i l a m e n t s
are split by s l i g h t o e d e m a , a n d t h e blood c a p i l l a r i e s are e n g o r g e d . H e r e a n d there s m a l l fresh p u n c t i f o r m h e m o r r h a g e s a r e s e e n , a s w e l l a s small a c c u m u l a t i o n s of l y m p h o c y t e s , a n d a f e w small cicatricial s t r a n d s . T h e r e is n o e m i g r a t i o n of l e u k o
-c y t e s . S p e -c i a l s t a i n i n g in t h e m a n n e r of Mahon s h o w e d d e g e n e r a t i o n s of the m e d u l l a r y s h e a t h s ; m o r e o v e r , there is s t a i n i n g of the a x i s - c y l i n d e r s , which show d i s t i n c t d e g e n e r a t i v e c h a n g e s . "
T h e r e is not the lightest doubt that these o b v i o u s c h a n g e s ( o e d e m a of the nerve trunk, f i b r i n o u s e x s u d a t i o n , fresh h a e m o r r h a g e and marked de-g e n e r a t i o n of a x i s - c y l i n d e r s a n d m e d u l l a r y sheaths, a s m a l l v e i n contain-i n g o r g a n contain-i z e d r e m n a n t s of a t h r o m b u s , and between nerve and nerve sheath an a c c u m u l a t i o n of f l u i d c o n s i s t i n g of o e d e m a - f l u i d and f i b r i n ) are due to disturbances of the b l o o d s u p p l y . N o s i g n s of i n f e c t i o n , either m a c r o
or m i c r o s p i c , were e n c o u n t e r e d .
b ) The mastoids cells. W h e r e a s m o s t authors h a v e b e e n c o n c e r n e d to present c o n d i t i o n of the f a c i a l nerve, I have rather described alterations of the s u r r o u n d i n g s y s t e m : the m a s t o i d c e l l s and the w a l l of the facial c a n a l . T h e a l t e r a t i o n s of the m a s t o i d c e l l s f a l l into two g r o u p s :
Group 1 — T h i s g r o u p c o m p r i s e s 6 c a s e s : in 4 the c o m p l e t e p a l s y
T h e last 2 cases b e l o n g to the c l i n i c a l g r o u p " i n c o m p l e t e s p o n t a n e o u s r e c o v e r y " . A very t h o r o u g h m e d i c a l , n e u r o l o g i c a l , o t o l o g i c a l and radio-l o g i c a radio-l e x a m i n a t i o n s h o w e d n o t h i n g a b n o r m a radio-l apart f r o m the f a c i a radio-l p a radio-l s y , e s p e c i a l l y n o s i g n s of o t o g e n o u s i n f e c t i o n s . T h e m a s t o i d c e l l s between the p o s t e r i o r o s s e o u s w a l l of the e x t e r n a l a u d i t o r y canal and the s i g m o i d s i n u s , i n c l u d i n g the w h o l e tip of the m a s t o i d p r o c e s s were soft, often c o m p l e t e l y n e c r o t i c , g e n e r a l l y dark c o l o u r e d , and in o n e case c o n t a i n e d a dark clear f l u i d . T h e r e were no s i g n s of p u s or g r a n u l a t i o n tissue. T h e necrotic o s s e o u s tissue w a s r e m o v e d like butter with a curette as in a w e l l d e f i n e d m a s t o i d i t s . T h e result of m i c r o s c o p i c e x a m i n a t i o n w i l l be dealt with later.
Group 2 — In 1 4 cases the p a t h o l o g i c a l a l t e r a t i o n s were o n l y f o u n d
around the s t y l o m a s t o i d f o r a m e n a n d in the tip of the m a s t o i d p r o c e s s , w h i l e the rest of the c e l l s were n o r m a l . A n e x a m p l e m a y be g i v e n :
A m a n a g e d 2 6 w a s a d m i t t e d on D e c e m b e r 8, 1944. H e had n e v e r h a d s u p p u r a t i v e o t i t i s m e d i a . S i x t e e n y e a r s b e f o r e a d m i s s i o n he s u d d e n l y e x p e r i e n c e d m a s -s i v e r i g h t - -s i d e d p e r i p h e r a l facial p a l -s y , "which -s u b -s i d e d c o m p l e t e l y in t h e c o u r -s e of a f e w m o n t h s . S i x y e a r s l a t e r a r e l a p s e o c c u r r e d , which s u b s i d e d only p a r t i a l l y . One y e a r prior t o a d m i s s i o n m a s s i v e l e f t - s i d e d , p e r i p h e r a l facial p a l s y s u d d e n l y a p p e a r e d , n o t a c c o m p a n i e d by a c o u s t i c o v e s t i b u l a r s y m p t o m s or pain. A t f i r s t there w a s i m p r o v e m e n t , b u t f o r t w o m o n t h s p r i o r t o a d m i s s i o n his condition h a d been s t a t i o n a r y . F a c i a l f u n c t i o n w a s d e c r e a s e d on both s i d e s , m o s t s t r i k i n g l y o n the l e f t side. O t o s c o p y , a c o u s t i c e x a m i n a t i o n , r o e n t g e n s t u d y of the ears a n d t h e r e m a i n i n g o b j e c t i v e e x a m i n a t i o n s s h o w e d n o r m a l c o n d i t i o n s .
On D e c e m b e r 11, d e c o m p r e s s i o n of t h e l e f t facial n e r v e w a s p e r f o r m e d , a n d the f o l l o w i n g record w a s m a d e : " A l a r g e cellular s v s t e m is d i s c l o s e d , w h i c h is m a c r o s c o p i c a l l y normal. T h e e x t e r n a l shell o f t h e f a c i a l canal is e n o r m o u s l y h a r d , but the interior is s o f t . T h e n e r v e is d i s t i n c t l y s w o l l e n a n d b u l g e s g r e a t l y a f t e r t h e n e r v e s h e a t h has been slit o p e n . " M i c r o s c o p i c e x a m i n a t i o n revealed s l i g h t g r a n u l a r d e c a y o f t h e w a l l of t h e f a c i a l ean,al a n d d o u b t f u l incipient bony necrosis.
On D e c e m b e r 27, d e c o m p r e s s i o n of t h e r i g h t f a c i a l n e r v e w a s p e r f o r m e d , w i t h the f o l l o w i n g o b s e r v a t i o n s b e i n g r e c o r d e d : " T h e s u p e r f i c i a l cells a r e c o m p l e t e l y normal. T h e n e r v e is s o u g h t o u t a t t h e s t y l o m a s t o i d f o r a m e n , a n d m o r e t h a n half t h e w a y t o t h e l a t e r a l s e m i c i r c u l a r c a n a l a f o c u s is reached in t h e p a r t d e e p
t o t h e f a c i a l canal. H e r e t h e bone i s e x t r e m e l y s o f t a n d is s c r a p e d o u t like butter. A f t e r removal of all d e c a y e d o s s e o u s t i s s u e , t h e bulb of t h e j u g u l a r vein lias p r a c t i c a l l y been reached. T h e c a v i t y p a s s e s 1.3 c m . below t h e n e r v e , m e a s u r -i n g 2.5 c m . p r o x -i m o d -i s t a l l y , a n d o f f t h e c o u r s e of t h e n e r v e -in t h e f a c -i a l c a n a l the f u n n e l - s h a p e d c a v i t y h a s a w i d t h of 0.5 cm. W h e n the n e r v e sheath is slit o p e n , t h e n e r v e b u l g e s distinctly."
In 10 of these cases, the p a l s y h a d lasted between 1 ½ a n d 4 m o n t h s . In 4 it lasted l o n g e r . Like the p a t i e n t s in g r o u p 1, the f a c i a l p a l s y w a s the o n l y c l i n i c a l s y m p t o m .
In each case a m i c r o s c o p i c e x a m i n a t i o n was performed by Dr. Svend
Petri, chief of the p a t h o l o g i c a l institute of the M u n i c i p a l H o s p i t a l of
Copen-h a g e n , and it agreed in s Copen-h o w i n g granular decay of tCopen-he b o n e , particularly
b o n y necrosis, and in a s i n g l e case e n c h o n d r o m a t o u s alteration of the s p o n g y
o s s e o u s tissue, but never p u s , round cell i n f l a m m a t i o n or granulation tissue.
c ) The facial canal. N o r m a l l y the w a l l of the facial canal is like
ivory and it is a hard and time c o n s u m i n g task to o p e n it, but in 2 6 out of
108 cases the canal was p a t h o l o g i c a l . In some cases it was very
pro-n o u pro-n c e d :
A w o m a n , 37 y e a r s of a g e . She has n e v e r s u f f e r e d f r o m o t i t i s m e d i a . T h r e e y e a r s before a d m i s s i o n a c o m p l e t e f a c i a l p a l s y on t h e right side d e v e l o p e d s u d denly. S h e r e c o v e r e d o n l y p a r t i a l l y and for t h e l a s t y e a r there had been no p r o -g r e s s . A p a r t f r o m t h e p a l s y n o t h i n -g a b n o r m a l w a s f o u n d .
In a few cases I have seen the nerve e x p o s e d as described above, in
others the canal was not open but c o m p l e t e l y soft and c o u l d be opened
as far as the lateral horizontal canal in a few minutes. In some cases the
exterior shell was hard, and a l t h o u g h the interior layer was soft, this
w o u l d not have been detected if there had not been a search for p a t h o l o g i c a l
changes. M i c r o s c o p i c e x a m i n a t i o n s h o w e d decay of the osseous tissue
proper, v a r y i n g between slight and more marked.
Comments — There is general agreement over the description of the
facial nerve itself in cases of i s c h a e m i c palsy, but o p i n i o n s differ with
regard to the p a t h o l o g i c a l changes in m a s t o i d c e l l s and the w a l l of the
facial canal. H i l g e r
1 8and S k i n n n e r
3 9stress that m y f i n d i n g s have not
been confirmed b y others with s i g n i f i c a n t e x p e r i e n c e . T h i s is partly true,
but o n l y of A m e r i c a n and E n g l i s h authors, since they have been confirmed
by Scandinavian surgeons. S k o o g
4 0writes as f o l l o w s in a personal
com-m u n i c a t i o n : "Frocom-m com-m y experience regarding rheucom-matic facial p a l s y 1 acom-m
c o m p l e t e l y convinced that y o u are right. In m y last 3 cases I remember
that osseous alterations were encountered around the facial canal,
im-m e d i a t e l y above the s t y l o im-m a s t o i d f o r a im-m e n . In one case a very p r o n o u n c e d
h y p e r a e m i a with soft b o n e , in a s e c o n d a d i s c o l o u r e d and thickened m u c o u s
membrane, and in a third two small c e l l s just near the facial canal f i l l e d
with a fibrinous, y e l l o w transudate or exsudate were f o u n d " ( p u b l i s h e d
by p e r m i s s i o n of Prof. S k o o g ) .
H a l l
1 7f o u n d in 3 cases an "exsudate in the c e l l s at the tip of the
mastoid process, and in one some larger c e l l s c o n t a i n i n g a y e l l o w serous
fluid. The b o n e near the s t y l o m a s t o i d foramen was definitely soft, and
the facial nerve h i g h l y o e d e m a t o u s " . H e later encountered a fourth c a s e :
Case of c o m p l e t e Bell's p a l s y of 9 weeks duration. At
decompres-sion the superficial c e l l s were n o r m a l , but in the tip of the mastoid process
and in the surrounding of the s t y l o m a s t o i d foramen the bone was necrotic,
no pus, no g r a n u l a t i o n tissue, the nerve sheath was s w o l l e n and on slitting
it the nerve s w e l l e d to more than d o u b l e its size.
S i m i l a r findings are reported by F l o d g r e n
1 4. Consequently, when
c o m p a r i n g the descriptions of A n g l o - S a x o n and S c a n d i n a v i a n authors, it
m a y be worth r e m e m b e r i n g the w o r d s of the American Martin
2 6: " P e r h a p s
we do not get the severe neurocirculatory b l o c k s our more northerly
neigh-bors do".
Pathogenesis
In recent years general agreement has been reached that "Bell's p a l s y " ,
"rheumatic facial p a l s y " , or as it ought to be termed "ischaemic facial
palsy", is due to vascular disturbances near the s t y l o m a s t o i d foramen, a
dysrégulation of the vasa nervorum.
Audibert, Mattei a n d P a g a n e l l i
3expressed the belief that when a patient
gets sudden m a s s i v e attack of peripheral facial p a l s y , after suffering,
per-h a p s , f r o m a per-half a day's or a day's p a i n beper-hind tper-he ear but otper-herwise
d i s p l a y i n g n o a b n o r m a l s y m p t o m s , it can be e x p l a i n e d i n one w a y o n l y :
"The vascular s u p p l y of the nerve has been b l o c k e d " . In an extremely
interesting work these authors have rendered the theory of a failure of
the b l o o d s u p p l y as the cause of Bell's p a l s y p r o b a b l e , and they have
m a i n t a i n e d : "La p a r a l y s i e f a c i a l e p é r i p h é r i q u e dite "a f r i g o r e " est fonction
d'une atteinte artérielle des vasa-nervorum ( T h e peripheral facial p a r a l y s i s
c a l l e d "a f r i g o r e " is an effect of an arterial disturbance of the vasa
ner-v o r u m ) " . T h e y do not use the e x p r e s s i o n "une lésion", as this w o u l d
i m p l y a serious p r o g n o s i s and therefore c o u l d not be a p p l i e d to the slight
a n d transient type of paresis, but they use the term "atteinte" ( s l i g h t
i n j u r y ) .
The fact that in s o m e patients the facial nerve degenerates c o m p l e t e l y ,
with e n s u i n g permanent paresis, p r o v e s that the nerve has been v i t a l l y
affected. T h e same authors criticize the term "a f r i g o r e " a n d ask, "When
a patient gets a h e m i p l e g i a or a h e m i p a r e s i s , do w e then speak of a paresis
"à f r o i d " ? W e don't, but we k n o w it is a case of s p a s m , thrombosis or
e m b o l i s m , all of them dependent on a disturbance of the b l o o d s u p p l y " .
Continuing, they express the view that exactly the same a p p l i e s to the
facial n e r v e : a b l o c k of the vessels of the nerve is the o n l y way in w h i c h
the s u d d e n l y o c c u r r i n g facial p a l s y can be e x p l a i n e d ; if the block does
not occur s u d d e n l y , the b l o o d s u p p l y f a i l i n g o n l y g r a d u a l l y , the paresis
d e v e l o p s little b y little.
This discordance of o p i n i o n s m a y , I s u p p o s e , be o n l y apparent, as
n o t h i n g e x c l u d e s the p o s s i b i l i t y that the c o o l i n g acts on the vessels of the
nerve, disturbing the b l o o d s u p p l y .
In a most interesting paper H i l g e r
1 8deals with the pathogenesis, the
primary feature of w h i c h , as already m e n t i o n e d , is an arteriolar
con-striction, the i m p e t u s b e i n g derived f r o m a u t o n o m i c nervous i m p u l s e s to
the vessel concerned. "It is p r o b a b l e that the tendency is a c t u a l l y inherited
The vessels of most vital p h y s i o l o g i c import in any arterial trunk
system are the arterioles. Because of the a n a t o m y of their autonomic
innervation in the peripheral vascular areas, arterioles tend to behave in
segmental arterial branch f a s h i o n rather than in diffuse, haphazard
man-ner. W h e n the arterioles of a s m a l l segmental branch of the carotid tree
constrict s i m u l t a n e o u s l y , the resultant ischaemia p r o d u c e s interesting clinical
c o n d i t i o n s in the tissues s u p p l i e d by that branch. T h e c o n d i t i o n s m a y
vary w i d e l y according to the cranial tissue i n v o l v e d . In the case of
end-arteries without collaterals, a peripheral cataclysm m a y occur as, for
e x a m p l e , in the inner ear. In a c o n f i n e d a n a t o m i c situation where
as-sociated o e d e m a is able b y c o m p r e s s i o n to prevent collateral arterial
sup-p l y , an a n a l o g o u s condition is created. Oedema within the firm fibrous
sheath of the facial nerve in the region of the s t y l o m a s t o i d f o r a m e n is an
e x a m p l e " .
H i l g e r
1 8has described the p r o b a b l e m e c h a n i s m as f o l l o w s : The
es-sential features are arteriolar constriction, f o l l o w e d by c a p i l l a r y dilatation,
an increase in p e r m e a b i l i t y , and resultant transudation. The c a p i l l a r y
di-latation m a y f o l l o w ischaemic d a m a g e , or result r e f l e x l y f r o m the fall in
venous pressure. T h e pressure of f l u i d transudates is r a p i d l y transmitted
to the w a l l s of the l y m p h c a p i l l a r i e s , and they m a y be c l o s e d by
compres-sion. A d d i t i o n a l f l u i d then a c c u m u l a t e s , and c o m p r e s s i o n of c a p i l l a r i e s
a n d venules within the F a l l o p i a n canal creates further zonal ischaemia,
so that a v i c i o u s circle arises.
C o l l i e r
9e x p l a i n s on this basis the fact that a reversible ischaemic
block m a y bé present for l o n g p e r i o d s in the nerves of the limbs without
l e a d i n g to permanent change, w h i l e the same b l o c k ocurring in the rigid
facial canal w i l l p r o d u c e i n c r e a s i n g vascular stasis and o e d e m a , leading
to c o m p l e t e degeneration. The ' s c h a c r i a nffecis p r i m a r i l y the m y e l i n
sheath and h a s at first little if any influence on the S c h w a n n c e l l s and
axis c y l i n d e r s , which o n l y degenerate after a p r o l o n g e d lack of b l o o d
s u p p l y . In such cases the nerve may on e x p o s u r e be seen to be reduced
to an atrophic strand
8-
2 2 > 3 1-
4 4.
C o l l i e r
9has c a l l e d attention to the fact that ischaemia m a y produce
a m i x e d l e s i o n , some of the a x o n s u n d e r g o i n g degeneration, w h i l e others
remain in a condition of reversible block and are c a p a b l e of recovering.
As l o n g as the sheaths of S c h w a n n maintain patent s y n c y t i a l c h a n n e l s the
a x i s c y l i n d e r s can regenerate and re-establish their continuity.
F r o m the point of view of p a t h o l o g i c a l a n a t o m y , there is no doubt that
a dysregulation of the vasa nervorum takes p l a c e near the s t y l o m a s t o i d
foramen with e n s u i n g s w e l l i n g of the nerve, w h i c h b e c o m e s s e c o n d a r i l y
compressed within the F a l l o p i a n canal. H o w e v e r , there h a s been some
discussion over the exact sequence of events in p a t h o g e n e s i s .
Bal-lance and D u e l
4c l a i m e d that the reason for the p a l s y was a s w e l l i n g of
the facial nerve, w h i c h lost its p o w e r of conduction because it became
com-pressed within the facial canal. But Cawthorne
8, F i n d l a y
1 S, H i l g e r
1 8and
Kettel
2 2have p o i n t e d out that the p r i m a r y cause of the p a l s y is an
ischae-mia of the nerve, and that its p o w e r of conduction is lost f o l l o w i n g failure
of the b l o o d s u p p l y . R e s u l t i n g from this lack of b l o o d a s w e l l i n g of the
nerve then d e v e l o p s , f o l l o w e d by a secondary c o m p r e s s i o n within the facial
canal, with all its consequences. S u l l i v a n
4 1also agrees that disturbance
of b l o o d s u p p l y is the first cause of this p a l s y , but thinks that the paralysis
is a result of pressure u p o n the nerve f o l l o w i n g o e d e m a in the rigid
canal.
That the p r i m a r y ischaemia and not the secondary compression is the
reason for the nerve l o s i n g its power of conduction is illustrated by the
f o l l o w i n g f a c t s : 1) L e w i s , P i c k e r i n g and R o t s c h i l d
2 4and D e n n y - B r o w n
and B r e n n e r
1 1have s h o w e d that p a r a l y s i s due to pressure on a nerve
is entirely due to i s c h a e m i a . G r u n d f e s t
1 6has also s h o w n that the
pres-sure necessary to a b o l i s h conduction in a nerve is one which never occurs
c l i n i c a l l y . 2 ) Recently I have seen two patients, on w h o m I h a d earlier
performed d e c o m p r e s s i o n , suffering from a relapse of their facial palsy —
as w i l l be described later. If the p a l s y were due s o l e l y to secondary
com-pression within the facial canal, a relapse w o u l d be i m p o s s i b l e , since the
nerve h a d p r e v i o u s l y been e x p o s e d for 3 / 4 of its width f r o m the lateral
semicircular canal to the s t y l o m a s t o i d f o r a m e n .
Even if i s c h a e m i a is thus the p r i m a r y cause of the p a r a l y s i s , it is
nevertheless a fact that a secondary c o m p r e s s i o n of the nerve, and e s p e c i a l l y
of its v e s s e l s , in the facial canal does occur. The p o w e r of conduction
is thus further i m p a i r e d , not because the nerve is c o m p r e s s e d , but because
its b l o o d s u p p l y is further reduced.
Etiology
In this p a p e r the t e r m Bell's p a l s y is r e s t r i c t e d t o c a s e s in w h i c h the facial p a l s y is t h e o n l y clinical s y m p t o m , a n d in w h i c h it has been i m p o s s i b l e to d e -m o n s t r a t e a local c a u s e . C o n s e q u e n t l y all c a s e s in which the f a c i a l p a l s y is due to i n f e c t i o n s in t h e n i g h b o r h o o d are e x c l u d e d .
I t should i m m e d i a t e l y be s t a t e d t h a t our k n o w l e d g e of the e t i o l o g y is e x t r e m e l y m e a g e r .
Bell's p a l s y is d u e to ischaemia of the facial n e r v e a n d the i m p e t u s t o a r t e r i o l a r c o n s t r i c t i o n is d e r i v e d from a u t o n o m i c n e r v o u s i m p u l s i o n i s . T h i s h o w e v e r m a y be
released in v a r i o u s w a y s , physical and e m o t i o n a l .
E x p o s u r e to cold has been c i t e d a s the m o s t c o m m o n c a u s e ( a s high as 70 per c e n t ) , a n d this is w h y the t e r m s "rheumatic facial p a l s y " or "paresis n. facialis a f r i g o r e " a r e u s e d on the E u r o p e a n c o n t i n e n t i n s t e a d of "Bell's palsy". T h e r e is not t h e s l i g h t e s t d o u b t t h a t cold m a y p r o d u c e a B e l l ' s p a l s y " a n d t h e l i t e r a t u r e c o n t a i n s m a n y rather f u n n y e x a m p l e s . M o r e o v e r , S u l l i v a n a n d S m i t h4 2
have e x -p e r i m e n t a l l y -p r o v e d the c o r r e c t n e s s of this fact. B u t on t h e other hand the i m p o r t a n c e of e x p o s u r e to cold has been o v e r e s t i m a t e d . A m o n g W i n t e r n i t z 4
p a t i e n t s , e x p o s u r e to cold as an e t i o l o g i c f a c t o r c o u l d o n l y be p r e s u m e d in 15 p e r cent.
I f cold w e r e the all i m p o r t a n t f a c t o r , m o r e c a s e s w o u l d be e x p e c t e d d u r i n g the w i n t e r , a n d e s p e c i a l l y in v e r y c o l d w i n t e r s . T h i s , h o w e v e r , is not the case. W i n t e r n i t z 4 9 has p o o l e d the s t a t i s t i c s of v a r i o u s a u t h o r s r e c o r d i n g 644 c a s e s in a l l : in 332 p a t i e n t s the p a l s y arose d u r i n g the m o n t h s A p r i l - S e p t e m b e r , in 312 b e t w e e n O c t o b e r a n d March.
M o r e o v e r , d u r i n g t h e hard w i n t e r s 1939-40 a n d 1940-41 he did not see m o r e c a s e s of Bell's p a l s y t h a n d u r i n g m i l d w i n t e r s . F i f t y per c e n t of m y p a t i e n t s h a d been e x p o s e d to cold or d r a u g h t in t h e d a y s p r e c e e d i n g the o n s e t ; the i n f o r m a t i o n s , h o w v e r , w e r e t o o unreliable t o j u s t i f y d e f i n i t e conclusions. O n l y 83 of m y p a t i e n t s r e m e m b e r e d e x a c t l y the t i m e of o n s e t ( c h a r t 1 ) .
F i n a l l y it should be a d d e d t h a t B e l l ' s p a l s y has n o t h i n g a t all to do w i t h a r h e u m a t i c i n f e c t i o n 4 9 ,
E m o t i o n a l s t r a i n a n d allergic shock m a y also release t h e m e c h a n i s m l e a d i n g t o v a s o c o n s t r i c t i o n w i t h an e n s u i n g f a c i a l p a l s y . A r r i e t a 2 a n d B e r g o n z i 5 have r e p o r t e d c a s e s in which a Bell's p a l s y o c c u r r e d as a c o n s e q u e n c e of s u d d e n f r i g h t , P a n n e t o n 34 has d e s c r i b e d c a s e s of f a c i a l p a l s y in c o n n e c t i o n w i t h e x t r a c t i o n of a t o o t h , a n d I c a n p e r s o n a l l y c o n f i r m b o t h t h e i r s t a t e m e n t s .
Summarizing, it m a y be s a i d t h a t our k n o w l e d g e of t h e e t i o l o g y of Bell's p a l s y
or "paresis n. f a c i a l i s a f r i g o r e " s h o u l d be c o m p l e t e l y a b a n d o n e d and r e p l a c e d by term "ischaemic palsy".
F r o m m y p o i n t of view the q u e s t i o n of p a t h o l o g y n a r r o w s d o w n to t h i s : Bell's p a l s y is a p a t h o g e n e t i c e n t i t y , the p r i m a r y a n d c e n t r a l f e a t u r e b e i n g a d i s o r d e r , a " d y s r e g u l a t i o n " of the c i r c u l a t i o n , in m o s t c a s e s a f f e c t i n g only the n u t r i t i o n of t h e n e r v e a s the m o s t s u s c e p t i b l e t i s s u e . F r o m this a n ischaemic p a r a l y s i s a r i s e s . In o t h e r c a s e s the n u t r i t i o n of facial canal and m a s t o i d cells is also a f f e c t e d c a u s i n g bony n e c r o s i s . T h e r a p i d i t y w i t h w h i c h the p a r a l y s i s begins, t h e d e g r e e to w h i c h it d e v e l o p s , t h e t i m e it l a s t s a n d t h e d e g r e e of the p a t h o l o g i c c h a n g e s w h i c h m a y be n o t e d in t h e n e r v e a n d the o s s e o u s s t r u c t u r e s all d e p e n d on the size of t h e vessel t h a t is b l o c k e d a n d on t h e r a p i d i t y a n d t h e d e g r e e t o w h i c h t h e c i r c u l a t i o n is c u t o f f a n d , e v e n t u a l l y , re-established. T h e c a u s e m a y v a r y , a n d a t p r e s e n t not m u c h is k n o w n a b o u t it, but the p a t h o g e n e s i s is in all p r o b a b i l i t y t h e s a m e : a p r i m a r y ischaemic p a r e s i s of v a s c u l a r d e -t e r m i n a -t i o n .
S Y M P T O M A T O L O G Y
T h e p i c t u r e of a p a t i e n t w i t h a c o m p l e t e p e r i p h e r a l f a c i a l p a l s y is so well k n o w n t h a t a n y d e s c r i p t i o n w o u l d be s u p e r f l u o u s . I t should, h o w e v e r , be re-m e re-m b e r e d t h a t p a t i e n t s w i t h B e l l ' s p a l s y g i v e h i s t o r y of other re-m a n i f e s t a t i o n s of c a r o t i c v a s o m o t o r d i s t u r b a n c e , like chronic rhinitis, v a s o d i l a t i n g pain, c e r v i c a l m y a l g i a or v a s o m o t o r l a b y r i n t h i t i s i s .
I n t r y i n g t o check m y c a s e r e c o r d s f o r clinical s y m p t o m s I have been h a n d i c a p -ped by t w o f a c t s . F i r s t l y , m y r e c o r d s f r o m the e a r l y y e a r s of m y w o r k in t h i s field a r e i n c o m p l e t e , l a t e r all the p a t i e n t s have been q u e s t i o n e d s y s t e m a t i c a l l y , u s i n g a s p e c i a l q u e s t i o n a r y . S e c o n d l y , m o s t of m y p a t i e n t s w e r e r e f e r r e d t o m e because of d e l a y of r e c o v e r y , a n d m a n y had f o r g o t t e n t h e s y m p t o m s a t t h e o n s e t . O n l y t h o s e p a t i e n t s w h o e x a c t l y r e m e m b e r e d t h e s e s y m p t o m s d u r i n g the f i r s t d a y s of t h e p a l s y a r e i n c l u d e d in t h e f o l l o w i n g report.
T h e onset of the p a l s y m a y be s u d d e n or it m a y d e v e l o p g r a d u a l l y . N i n e t y - f i v e w e r e able to a n s w e r this q u e s t i o n : in 60 it d e v e l o p e d s u d d e n l y , in 35 g r a d u a l l y .
Pain, r a n g i n g f r o m s l i g h t t o r a t h e r s e v e r e , is a c o m m o n s y m p t o m s in th.; e a r l y
F i n d l a y 13 is p e r f e c t l y right t h a t s a m e p a t i e n t s w i t h i s c h a e m i c facial p a l s y m a y s u f f e r from p a i n a n d t h a t s e v e r e p a i n m a y b e a b a d p r o g n o s t i c s i g n , but m a n y c a s e s of the i s c h a e m i c p a l s i e s are p a i n l e s s .
F r o m 89 of m y p a t i e n t s I w a s able t o g e t e x a c t i n f o r m a t i o n of this s i m p t o m s a t the o n s e t of p a l s y : 43 h a d s u f f e r e d f r o m pain in o r e s p e c i a l l y b e h i n d t h e e a r ; in 29 of t h e s e t h e p a l s y had s t a r t e d s u d d e n l y , in 14 g r a d u a l l y . In 10 c a s e s t h e pain w a s s l i g h t , in 29 m o r e p r o n o u n c e d , a n d in 4 severe. A m o n g t h e 46 p a i n l e s s c a s e s the o n s e t w a s s u d d e n in 25, and g r a d u a l in 21 p a t i e n t s .
Loss of taste on t h e a n t e r i o r t w o t h i r d s of t h e t o n g u e w a s n o t e d b y 36 p a t i e n t s ,
w h e r e a s 30 d i d not r e m e m b e r h a v i n g been t r o u b l e d by this s y m p t o m .
A s l i g h t oedema behind the ear m a y be n o t e d in t h e e a r l y d a y s of a Bell's p a l s y , and is p r o b a b l y d u e t o v e n o u s s t a s i s . A s m o s t of m y p a t i e n t s w e r e r e f e r -red to m e because of d e l a y of r e c o v e r y . I have seen this in o n l y 5 c a s e s , 4 of them a c c o m p a n i e d by p a i n .
Injection of the p o s t e r i o r wall of t h e e x t e r n a l m e a t u s a n d t h e p o s t e r i o r p a r t
of the t y m p a n i c m e m b r a n e is p r o b a b l y d u e t o a r t e r i o l o s p a s m , which c a n p r o d u c e d i l a t a t i o n in their a r t e r i a l trunk. L i k e H i l g e r I h a v e seen it in the first clays of t h e palsy.
Hyperacusis results f r o m s t a p e d i a l n e r v e p a r a l y s i s , in other p a t i e n t s t h e
hear-i n g hear-is hear-i m p a hear-i r e d b e c a u s e of a c o l l a t e r a l o e d e m a of the l a b y r hear-i n t h a n d t h e y o f t e n s u f f e r f r o m buzzing in the ear.
I t is i n t e r e s t i n g t o n o t e t h a t h y p e r a c u s i s a n d l o s s of t a s t e , w h i c h are o f t e n p r e s e n t e a r l y in Bell's p a l s y , m a y s o o n d i s a p p e a r in s p i t e of c o n t i n u e d facial palsy. T h i s is p r o b a b l y due t o relief of i s c h a e m i a t h r o u g h v a s c u l a r a n a s t o m o s e s a t the knee of t h e facial n e r v e , while t h e r e is n o collateral s u p p l y b e l o w t h i s l e v e l s ( H i l g e r ) .
S e v e n t y p a t i e n t s w e r e able to a n s w e r q u e s t i o n s a b o u t their h e a r i n g at the o n s e t : 10 p a t i e n t s c o m p l a i n e d of i m p a i r e d h e a r i n g a n d buzzing in t h e e a r , in 60 t h e h e a r i n g w a s normal. T h e s e s y m p t o m s d i s a p p e a r e d in a s h o r t time, in s p i t e of p e r s i s t e n t p a l s y .
Vertigo m a y be p r e s e n t d u r i n g the f i r s t d a y s . A c c o r d i n g t o t h e t h e o r y of
M y g i n d and D e d e r d i n g which has g r a d u a l l y been u n i v e r s a l l y a c c e p t e d , Meniere's d i s e a s e is due to an o e d e m a of the l a b y r i n t h which is d e p e n d e n t on f a i l u r e of the v a s o m o t o r f u n c t i o n . T h e a u t h o r s t h e n p o i n t e d tjut t h a t , j u s t as the s y m p t o m s in Meniere's d i s e a s e are c a u s e d b y o e d e m a a r i s i n g in t h e n a r r o w , i n e l a s t i c l a b y r i n t h , so Bell's p a l s y is p r o d u c e d b y o e d e m a of the f a c i a l n e r v e a r i s i n g in t h e n a r r o w , i n e l a s t i c F a l l o p i a n canal. T h i s view w a s c o n f i r m e d by the f a c t t h a t in several c a s e s they had seen an i m p r o v e m e n t of the p a r e s i s on a d m i n i s t r a t i o n of a p o w e r -ful diuretic.
In II p a t i e n t s a slight v e r t i g o w a s p r e s e n t a t the s t a r t , in 61 no l a b y r i n t h i n e s y m p t o m s w e r e r e m e m b e r e d . S i x t y - s i x p a t i e n t s c o u l d g i v e e x a c t a n s w e r s as to both h e a r i n g a n d e v e n t u a l v e r t i g o ( i m p a i r m e n t of h e a r i n g and v e r t i g o are probably d u e to a collateral o e d e m a of the l a b y r i n t h ) :
In m y m a t e r i a l p e r s o n s b e t w e e n 20 a n d 40 y e a r s of age w e r e m o s t c o m m o n l y a f f l i c t e d , a n d this is in a c c o r d a n c e w i t h s t a t i s t i c s b y W i n t e r n i t z 4 9 , P h i l i p p 3 6 , G o r d e r s i 5 , B e r n h a r d t s a n d W a t e r m a n 4 7 .
T h e influence of sex is of no d e c i s i v e i m p o r t a n c e . A m o n g Midler's 33 226 p a t i e n t s 107 w e r e m a l e , 119 f e m a l e . W i n t e r n i t z 4 9 t r e a t e d 233 c a s e s , 117 m a l e , 116 female. M o r e o v e r , he a d d e d his f i g u r e s t o t h o s e of P h i l i p p , G o w e r s a n d B e r n h a r d t , a n d a m o n g 545 c a s e s 51 p e r c e n t w e r e m a l e , 49 per c e n t f e m a l e . W a t e r -m a n 47 r e p o r t s 968 c a s e s , 52 p e r c e n t -m a l e a n d 48 p e r c e n t f e -m a l e . S e v e n t y f o u r of m y 108 p a t i e n t s w e r e f e m a l e , o n l y 34 m e n , but m y m a t e r i a l is p u r e l y s u r g i c a l a n d s e l e c t e d , as m o s t of m y p a t i e n t s w e r e r e f e r r e d to m e b e c a u s e of d e l a y in recovery. T h e w o m e n w e r e o b v i o u s l y m o r e t r o u b l e d b y t h e p a l s y , a n d c o n s e q u e n t l y m o r e e a g e r to c o n s u l t a s u r g e o n ( t a b l e 2 ) .
I t m a y finally be m e n t i o n e d t h a t in facial p a l s y there is a tendency to familial
history and recurrences.
T h e p a l s y m a y a p p e a r s u d d e n l y or d e v e l o p g r a d u a l l y , be c o m p l e t e or o n l y p a r t i a l , d i s a p e a r in a s h o r t t i m e or remain f o r a l o n g p e r i o d . I t m a y be p u r e l y m o t o r or c o m b i n e d w i t h s e n s o r y or s e c r e t o r y s y m p t o m s , it m a y be r e s t r i c t e d t o the area i n n e r v a t e d b y t h e f a c i a l n e r v e i t s e l f or c o m b i n e d w i t h s y m p t o m s f r o m t h e n e i g h b o r i n g o r g a n s , b u t e v e r y t h i n g ( r a p i d i t y of d e v e l o p m e n t , d e g r e e , c h a n c e s of r e c o v e r y ) d e p e n d s u p o n one t h i n g a n d o n e t h i n g o n l y : the severity of the
dys-regulation of the blood supply and the rapidity with which circulation is re-established in order to avoid degeneration of the axis cylinders.
D I A G N O S I S
clinical s y m p t o m , and in which it has been i m p o s s i b l e to demonstrate a
local cause.
Consequently a d i a g n o s i s of B e l l ' s p a l s y cannot s a f e l y be m a d e unless
the patient has been subjected to a t h o r o u g h m e d i c a l , n e u r o l o g i c a l ,
oph-t h a l m o l o g i c a l , o oph-t o l o g i c a l and r a d i o l o g i c a l e x a m i n a oph-t i o n oph-to e x c l u d e a local
cause, and even then one cannot be quite safe, as I have e x p e r i e n c e d t w i c e :
in one case the d e c o m p r e s s i o n revealed a n e u r i n o m a , in the other a sarcoma
of the descending part of the facial nerve, between the lateral s e m i c i r c u l a r
canal and the s t y l o m a s t o i d f o r a m e n , as p r e v i o u s l y described. Cawthorne
h a s had the same e x p e r i e n c e . P r o v i d e d a local causation h a s been e x c l u d e d
to the extent c l i n i c a l l y p o s s i b l e , our endeavours s h o u l d be directed to
de-terming ( 1 ) the site of the lesion and ( 2 ) the condition of the nervous
elements and the m u s c l e s .
Clinical topognosis — The facial nerve is, as m e n t i o n e d , a m i x e d
nerve, not o n l y s u p p l y i n g the emotional m u s c l e s with motor i m p u l s e s , but
also c o n t a i n i n g sensory, secretory and gustatory fibres. The clinical picture
is dependent upon the degree to w h i c h these different fibres of the nerve
are i n v o l v e d and this again u p o n the l o c a t i o n of the lesion. T s c h i a s s n y in
two p a p e r s
4 5h a s described the s i g n s characteristic of facial nerve lesions
at 8 different levels from supranuclear to i n f r a f o r a m i n a l . Reference s h o u l d
be made to this p a p e r for further i n f o r m a t i o n . In the ischaemic facial
p a l s y the dysrégulation of the b l o o d s u p p l y of the nerve is located distal
to the g e n i c u l a t e g a n g l i o n , and characteristic of this site of l e s i o n s are
( 1 ) that the secretion of tears is n o r m a l as the secretory fibres pass above
this level and ( 2 ) that a partial or c o m p l e t e p a l s y of the e m o t i o n a l
m u s c l e s with a p o s i t i v e Bell's p h e n o m o n is present.
If the vessels are blocked b e l o w the exit of the chorda tympani,
w h i c h contains gustatory fibres to the anterior two thirds of the tongue,
the sense of taste in the c o r r e s p o n d i n g area is normal ; if, however, the
site of lesion is above this level, loss of taste results. T h e presence or
absence of the stapedius reflex can f i n a l l y tell whether the suprachovdal
lesion is infra or suprastapedial respectively.
The v a l u e of this t o p o g n o s i s of f a c i a l nerve lesion is limited and can
be a p p l i e d with r e l i a b i l i t y o n l y to e a r l y l e s i o n s
4'°. C a w t h o r n e
8and
Sul-l i v a n
4 1c l a i m that loss of taste is the o n l y realiable s y m p t o m ; like Martin
2 6I w o u l d not even go as far a s that.
Electrodiagnosis — T h e n e r v e and t h e f a c i a l m u s c l e s should be t e s t e d by the
f a radie and g a l v a n i c c u r r e n t s , a n d by e l e c t r o m y o g r a p h y :
a ) Faradism is an i n t e r r u p t e d high f r e q u e n c y c u r r e n t which g i v e s direct s t i m u l a t i o n of short d u r a t i o n t o n e r v e s ; t h r o u g h t h e n e r v e s t h e m u s c l e s receive the i m p u l s e s to c o n t r a c t , n o r m a l l y at low i n t e n s i t i e s . If fa radie r e s p o n s e is lost, this o c c u r s 10-14 d a y s a f t e r onset.
-¡ng and b r e a k i n g the c i r c u i t ; n o r m a l l y the c a t h o d e c l o s i n g c u r r e n t e l i c i t a t e s a s t r o n g e r c o n t r a c t i o n t h a n t h e a n o d e c l o s i n g current. T h e r e a c t i o n of d e g e n e r a t i o n is s a i d t o be c o m p l e t e if f a r a d i s m is a b s e n t a n d t h e a n o d e c l o s i n g c u r r e n t elicits a s t r o n g e r c o n t r a c t i o n t h a n the c a t h o d e c l o s i n g current. I t is p a r t i a l if some r e s p o n s e t o f a r a d i s m is p r e s e n t , a n d t h e p o l a r r e s p o n s e is m o d i f i e d w i t h o u t b e -i n g reversed.
c ) Electromyography'. B y this m e t h o d it is p o s s i b l e to r e c o r d t h e action c u r r e n t in a v o l u n t a r y m u s c l e . T h e aim is t o o b t a i n a q u a n t i t a t i v e e s t i m a t i o n of the p r o p o r t i o n of n o r m a l m u s c l e t o t h e d e n e r v a t e d one which f a r a d i s m and g a l v a n i s m d o not p r o v i d e . T h e m e t h o d has been d e s c r i b e d by F e i n s t e i n 12 and W e d d c l l , F e i n s t e i n a n d P a t t l e 4 8 a n d by Collier 9. In c o m p l e t e l y d e n e r v a t e d m u s c l e s a r h y t h m i c a c t i v i t y c a l l e d f i b r i l l a t i o n , w h i c h is a s i g n of an a u t o n o m o u s life of the m u s c l e , o c c u r s a b o u t t h e 12th d a y , and can be o b t a i n e d as l o n g as a n y c o n t r a c t i l e m u s c l e f i b r e s remain. If r e - i n n e r v a t i o n o c c u r s t h e m u s c l e s a g a i n be-come silent. A m o t o r u n i t is t h e g r o u p of m u s c l e fibres s u p p l i e d by one n e r v e
fiber. N o e l e c t r i c a l a c t i v i t y is d e t e c t e d u n d e r r e s t i n g c o n d i t i o n s in a normal m u s c l e , but in v o l u n t a r y c o n t r a c t i o n all t h e m u s c l e fibres of the m o t o r unit c o n t r a c t s i m u l t a n e o u s l y a n d this can be recorded. T o t a l a b s e n c e of m o t o r u n i t p o t e n t i a l s a n d t h e p r e s e n c e of fibrillation a c t i o n p o t e n t i a l s i n d i c a t e c o m p l e t e d e -n e r v a t i o -n . T h e p r e s e -n c e of both is e v i d e -n c e of p a r t i a l or r e c o v e r i -n g lesio-n. Col-lier 9
s t a t e s t h a t s i n c e she has had the a s s i s t a n c e of e l e c t r o m y o g r a p h y she has not seen a n y c a s e of B e l l ' s p a l s y t h a t c a l l e d for d e c o m p r e s s i o n .
A s to galvanism, t h e r e is g e n e r a l a g r e e m e n t t h a t f a i l u r e to elicite a g a l v a n i c r e s p o n s e in m u s c l e s i n d i c a t e s serious a t r o p h y a n d c o n s e q u e n t l y c o n t r a i n d i c a t e s a n y o p e r a t i o n a i m e d at r e p a i r i n g the f a c i a l nerve. In such c a s e s only p l a s t i c o p e r a -t i o n s should, if n e c e s s a r y , b e resor-ted -t o .
O p i n i o n s r e g a r d i n g t h e v a l u e of faradism as an i n d i c a t o r for o p e r a t i o n d i f f e r widely. I n S u l l i v a n ' s4 1
opinion the response t o t h e f a r a d i c c u r r e n t is m o s t im-p o r t a n t , and in q u e s t i o n a b l e c a s e s , with the im-p a t i e n t a n a e s t h e t i z e d he e x im-p o s e s the n e r v e d i r e c t l y a t t h e s t y l o m a s t o i d f o r a m e n in o r d e r to be able t o u s e a suf-ficiently s t r o n g c u r r e n t , a n d a v o i d skin r e s i s t a n c e . T i c k l e4 4
a n d C a w t h o r n e8 also rely u p o n the r e s p o n s e t o f a r a d i s m as an i n d i c a t o r for o p e r a t i o n . T h e relation of d e g r e e of p a r a l y s i s and electrical c o n d u c t i v i t y to s p o n t a n e o u s r e c o v e r y in 151 c a s e s of B e l l ' s p a l s y t r e a t e d by C a w t h o r n e » is i l l u s t r a t i v e :
T h i s s t a t i s t i c s m a k e s C a w t h o r n e ' s8
L i k e M a r t i n 2
6 , V i o l é F i n d l a y i s a n d M a y e r 2 7
, I c o n s i d e r t h e f a r a d i c r e s p o n s e a n u n r e a l i a b l e i n d i c a t o r , h a v i n g seen m a n y a p a t i e n t w i t h n e g a t i v e f a r a d i c r e s p o n s e r e c o v e r c o m p l e t e l y u n d e r c o n s e r v a t i v e t r e a t m e n t . P r e v i o u s l y I t r i e d t o e x p l a i n this f a c t : w h e n a m u s c l e i s p a r a l y z e d , i t s e l e c t r i c e x c i t a b i l i t y i m m e d i a t e l y i n c r e a s e s ; i. e. t h e c h r o n a x i e of t h e m u s c l e is s h o r t e n e d , which m e a n s t h a t a s t i m u l u s of s h o r t e r d u r a t i o n i s c a p a b l e of e x c i t i n g c o n t r a c t i o n s . A f t e r a s h o r t p e r i o d of t i m e , h o w e v e r , t h e e x c i t a b i l i t y of t h e m u s c l e d e c r e a s e s ; in o t h e r w o r d s i t s c h r o n a x i e is e x t e n d e d , s o t h a t a s t i m u l u s of l o n g e r d u r a t i o n is required t o e x c i t e c o n t r a c t i o n s . T h e f a r a d i c c u r r e n t is a high f r e q u e n c y a l t e r n a t i n g c u r r e n t a n d t h e f a c t t h a t t h e f a r a d i c r e a c t i o n b e c o m e s n e g a t i v e j u s t m e a n s t h a t t h e s t i m u l u s i s i n a d e q u a t e because it is of t o o short d u r a t i o n t o e x c i t e c o n t r a c t i o n s of t h e m u s c u l a t u r e , t h e chronaxie of which h a s b e c o m e e x t e n d e d . T h e r e f o r e , no s a f e c o n c l u s i o n s a s t o t h e p r o g n o s i s of t h e p a r e s i s c a n be d r a w n f r o m a n e g a t i v e f a r a d i c r e a c t i o n .
H o w e v e r , I m u s t a d m i t t h a t I n e v e r e x p o s e d t h e n e r v e a n d a p p l i e d t h e cur-rent while t h e p a t i e n t w a s a n a e s t h e t i z e d , a s s u g g e s t e d b y S u l l i v a n *i.
F r o m t h e p a p e r s c i t e d a b o v e , it is a n e s t a b l i s h e d f a c t t h a t p a t i e n t s w i t h a n e g a t i v e f a r a d i c response m a y recover s p o n t a n e o u s l y a n d c o m p l e t e l y a n d t h a t n o t e v e n a n o r m a l f a r a d i c r e s p o n s e is a g u a r a n t e e f o r full s p o n t a n e o u s recovery.
R e g a r d i n g e l e c t r o m y o g r a p h y o p i n i o n s a l s o d i f f e r : S u l l i v a n H o u s e !» a n d V i o l é i s have f o u n d i t of little v a l u e , M a r t i n 2 0 , B u n n e l l ? a n d e s p e c i a l l y C o l l i e r s v e r y i m p o r t a n t . B u n n e l l " s t a t e s t h a t i t s r e s u l t s a r e 90 p e r c e n t reliable, b u t as an e m e r g e n c y g u i d e it is u s e l e s s , a s it is n o t of v a l u e b e f o r e 21 d a y s from t h e onset. E l e c t r o m y o g r a p h y m a y tell w h e t h e r a m u s c l e is c o m p l e t e l y d e n e r v a t e d or n o t , b u t by this m e t h o d it is i m p o s s i b l e t o d i s t i n g u i s h b e t w e e n a c o m p l e t e division of t h e n e r v e , w h e r e s p o n t a n e o u s r e g e n e r a t i o n is e x c l u d e d , a n d i n t e r r u p t i o n o f a x o n s w i t h p r e s e r v a t i o n of t h e s u p p o r t i n g s t r u c t u r e s , in which a x o n s c a n re-g e n e r a t e a l o n re-g t h e old p a t h s . O n l y e x p l o r a t i o n can d i s t i n re-g u i s h b e t w e e n t h e t w o lesions.
E s p e c i a l l y r e g a r d i n g Bell's p a l s i e s "we a r e d e a l i n g w i t h c a s e s w h e r e the original i n j u r y h a s p r o d u c e d a n i n t e r f e r e n c e w i t h c o n d u c t i o n w h i c h of itself is t e m p o r a r y a n d recoverable, b u t w h e r e p e r s i s t e n c e of t h e c o m p r e s s i o n in the rigid i a c i a l canal c a n p r o d u c e c h a n g e s w h i c h m a y l e a d t o d e g e n e r a t i o n " ( C a l l i e r s ) .
P e r s o n n a l l y I have n o e x p e r i e n c e w i t h e l e c t r o m y o g r a p h y .
Summarizing, it m a y be s a i d that a n e g a t i v e g a l v a n i c r e s p o n s e i n d i c a t e s
a s e r i o u s a t r o p h y of the m u s c l e s a n d c o n t r a i n d i c a t e s a n y o p e r a t i o n o n the f a c i a l n e r v e ; but that o p i n i o n s d i f f e r w i d e l y as to the v a l u e of the f a r a d i c r e s p o n s e and e l e c t r o m y o g r a p h y . T h e latter reaction m a y be an adjunct, but s h o u l d not be r e l i e d on e x c l u s i v e l y m o r e than a n y other f a c t o c2 6
. W h e n m o r e e x p e r i e n c e is g a i n e d w i t h e l e c t r o m y o g r a p h y , p e r h a p s p r o b l e m s m a y be s o l v e d , w h i c h cannot be o v e r c o m e t o d a y .
T H E R A P Y A N D P R O G N O S I S
K n o w i n g p r a c t i c a l l y n o t h i n g a b o u t its e t i o l o g y w e c a n n o t prevent B e l l ' s p a l s y f r o m a r i s i n g , but can o n l y try to c o m b a t the p r i m a r y cause, the i s c h a e m i a , and prevent or at least r e d u c e the s e c o n d a r y c o m p r e s s i o n w i t h i n the f a c i a l c a n a l .
