OTOACOUSTIC EMISSION
OSTEOPOROSIS
In osteoporosis, the density of bones
decreases, and their brittleness
increases, although there is no
change in size or composition.
Women past the menopause are the
most commonly affected because
their ovaries no longer produce
oestrogen, which helps to maintain
bone mass. The risk of the condition
is greater in a woman who undergoes
the menopause early, or whose
mother had osteoporosis.
B o n e m a r r o w
S o ft , s p o n g y
b o n e
H a r d , d e n s e
b o n e
Normal bone cross-section
Bone consists of fibres of collagen (a protein), which
give elasticity, and calcium, which gives hardness.
Bone loss with age
The graph on the right
shows how the
percentage of bone
lost increases in both
sexes from age 50
onwards, with the
losses particularly
marked in women
after the menopause.
Byage 80, up to half
of all women have
sustained at least
one fracture due to
osteoporosis, a much
higher proportion
than in men.
Decrease %
L e s s d e n s e
b o n e
Osteoporotic bone
Thinning is mainly due to loss of collagen, which
takes calcium with it. Both hard and spongy bone
tissues are affected.
Bone tissue affected byosteoporosis
When compared with normal bone tissue (left), the
osteoporotic bone (right) is far less dense and
appears thin and brittle.
-o sto m y
A t e r m t h a t i s u s e d t o d e s c r i b e a s u r g i -
c a l o p e n i n g ( f o r e x a m p l e ,
c o l o s t o m y
)
o r
a j u n c t i o n o f t w o h o l l o w o r g a n s .
o ta lg ia
T h e m e d i c a l t e r m f o r
e a r a c h e
.
OTC d ru g
S e e
o v e r - t h e - c o u n t e r d r u g .
o titis e x te rn a
I n f l a m m a t i o n o f t h e o u t e r - e a r c a n a l , c o m -
m o n l y d u e t o i n f e c t i o n ( s e e
E a r i n f e c t i o n s
b o x , o v e r l e a f ) . I t u s u a l l y c a u s e s s w e l l i n g ,
a d i s c h a r g e , a n d , i n s o m e p e o p l e ,
e c z e m a
a r o u n d t h e
o p e n i n g
o f t h e
e a r
c a n a l .
T h e e a r m a y b e i t c h y a n d p a i n f u l a n d
b l o c k e d w i t h p u s , c a u s i n g d e a f n e s s .
CAUSES
G e n e r a l i z e d i n f e c t i o n o f t h e c a n a l , a n d
s o m e t i m e s o f t h e p i n n a ( e x t e r n a l e a r ) ,
m a y
b e
d u e
t o
a
f u n g a l
o r
b a c t e r i a l
i n f e c t i o n . T h e e a r m a y a l s o s o m e t i m e s
b e c o m e
i n f l a m e d
a s
p a r t
o f
a
g e n -
e r a l i z e d
s k i n
d i s o r d e r
s u c h
a s
a t o p i c
e c z e m a o r s e b o r r h o e i c
d e r m a t i t i s
.
TREATMENT
O f t e n , t h e o n l y t r e a t m e n t r e q u i r e d i s t o
k e e p
t h e
e a r
c l e a n
a n d
d r y
u n t i l
t h e
i n f e c t i o n
h a s
c l e a r e d .
L o c a l l y
a c t i n g
p r e p a r a t i o n s
t h a t
c o n t a i n
a n t i b i o t i c
d r u g s ,
a n t i f u n g a l d r u g s
,
o r
c o r t i c o s t e r o i d
d r u g s
m a y b e u s e d . O r a l a n t i b i o t i c s m a y
b e g i v e n t o t r e a t b a c t e r i a l i n f e c t i o n s i f
t h e y a r e s e v e r e .
o titis m e d ia
I n f l a m m a t i o n o f t h e m i d d l e
e a r
, t h e c a v -
i t y b e t w e e n t h e e a r d r u m a n d t h e i n n e r
e a r , ( s e e
E a r i n f e c t i o n s
b o x , o v e r l e a f ) .
CAUSES
T h i s c o n d i t i o n i s d u e t o a v i r a l o r b a c t e r -
i a l i n f e c t i o n t h a t h a s u s u a l l y t r a v e l l e d u p
t h e
e u s t a c h i a n t u b e
,
t h e p a s s a g e t h a t r u n s
f r o m t h e b a c k o f t h e n o s e t o t h e m i d d l e
e a r . T h e t u b e m a y b e c o m e b l o c k e d b y
i n f l a m m a t i o n o r e n l a r g e d
a d e n o i d s
,
c a u s -
i n g f l u i d a n d / o r p u s t o a c c u m u l a t e i n
t h e m i d d l e e a r r a t h e r t h a n d r a i n i n g a w a y
t h r o u g h t h e t u b e . C h i l d r e n , p a r t i c u l a r l y
t h o s e u n d e r s e v e n y e a r s , a r e e s p e c i a l l y
s u s c e p t i b l e t o
o t i t i s m e d i a
b e c a u s e
o f
t h e s h o r t n e s s o f t h e i r e u s t a c h i a n t u b e s ;
s o m e c h i l d r e n h a v e r e c u r r e n t a t t a c k s .
SYMPTOMS
A c u t e
o t i t i s
m e d i a
c a n
c a u s e
s u d d e n
s e v e r e e a r a c h e , a f e e l i n g o f f u l l n e s s i n
t h e
e a r ,
d e a f n e s s ,
t i n n i t u s
( r i n g i n g
o r
b u z z i n g
i n
t h e
e a r )
a n d
f e v e r .
T h e
e a r d r u m
m a y
b u r s t ,
d i s c h a r g i n g
p u s
a n d r e l i e v i n g p a i n , i n w h i c h c a s e h e a l -
i n g u s u a l l y o c c u r s w i t h i n a f e w w e e k s .
DIAGNOSIS AND TREATMENT
T h e c o n d i t i o n i s d i a g n o s e d b y e x a m i n a -
t i o n o f t h e m i d d l e e a r w i t h a n
o t o s c o p e
;
t h e e a r d r u m a p p e a r s r e d a n d m a y b u l g e
o u t w a r d s . T r e a t m e n t
i s
w i t h
a n a l g e s i c
d r u g s
( p a i n k i l l e r s ) .
A n t i b i o t i c d r u g s
m a y b e
p r e s c r i b e d i f t h e i n f e c t i o n i s b a c t e r i a l .
COMPLICATIONS
A c o m p l i c a t i o n o f o t i t i s m e d i a i s
g l u e
e a r
,
i n w h i c h a t h i c k f l u i d b u i l d s u p i n
t h e
e a r
a n d
a f f e c t s
h e a r i n g .
G l u e
e a r
m a y
f o l l o w
s e v e r e
o r
r e c u r r e n t
o t i t i s
m e d i a , w h i c h o c c u r s m a i n l y i n c h i l d r e n .
I n
r a r e
c a s e s ,
t h e
i n f e c t i o n
s p r e a d s
i n w a r d s t o c a u s e
m a s t o i d i t i s
( i n f l a m m a -
t i o n o f t h e m a s t o i d b o n e i n t h e s k u l l ) .
oto-
P e r t a i n i n g
t o
t h e
e a r
,
a s
i n
o t o r r h o e a
( d i s c h a r g e f r o m t h e e a r ) .
o to a c o u s tic e m is s io n
A n
e c h o
e m i t t e d b y
t h e
i n n e r
e a r
i n
r e s p o n s e t o s o u n d . T h e e m i s s i o n i s p r o -
d u c e d o n l y b y a n o r m a l l y f u n c t i o n i n g
e a r a n d i s r e c o r d e d i n a t e s t t o d e t e c t
i m p a i r e d h e a r i n g .
O
575
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