the syndrome of normal-pressure hydrocephalus vassilioutis
TRANSCRIPT
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8/9/2019 The Syndrome of Normal-pressure Hydrocephalus Vassilioutis
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J N eurosurg 61 :501-50 9 , 1984
The syndrom e of normal-pressure hydrocephalus
JOHN VAS S ILOUTHIS, M . D.
Neurosurgical Department, Army Veterans Administration Hospital 417 NITS), Athens, Greece
~" A series of 40 patients with the sy ndro me of normal-pressure hydrocephalus is presented. Diagnosis w a s
based on clinical and computerized tomography (CT) scan criteria and was followed by the insertion of a
ventriculoperitoneal shun t in every instance. All patients responded favorably to trea tm ent (four of th em had
a fair outcom e), and this response was maintained. The re was one postoperative death, b ut no othe r serious
complications. This study demonstrates that it is possible to diagnose the syndrome of normal-pressure
hydrocephalus o n the basis of clinical and C T scan criteria w ithout an y oth er invasive investigations. Such
patients should re spond favorably to an adequately functioning shunting system.
K E Y W O R D S
9
n o r m a l - p r e s s u r e h y d r o c e p h a l u s 9 c o m p u t e r i z e d t o m o g r a p h y 9
v e n t r i c u l o p e r i t o n e a l s h u n t 9 h y d r o c e p h a l u s
T
HE te rm "norma l -p re s sure hydrocepha lus " (NP H)
i s u s e d t o d e s c r i b e a c l i n i c a l s y n d r o m e m a i n l y
c o m p r i s i n g ga i t d i s t u r b a n c e , d e m e n t i a , a n d u r i -
n a r y i n c o n t i n e n c e , a n d i s a s s o c i a t e d w i t h d i l a t a t i o n o f
t h e v e n t r ic u l a r sy s t em o f t h e b r a i n a n d n o r m a l c e r e b r o -
s p i n a l f l u i d ( C S F ) p r e s s u r e a t l u m b a r p u n c t u r e . 27 S i n c e
t h e i n i ti a l r e p o r t s f r o m t h e M a s s a c h u s se t s G e n e r a l H o s -
pi ta l , 1,2.46,47 nu m er ou s series o f pa t ien ts ap pa ren t ly suf-
f e ri n g f r o m t h i s s y n d r o m e h a v e b e e n d e s c r ib e d i n t h e
l it e ra tu re . 3-6'8'9"11'22'24"32-34'36'41'53'56'58'64 In these s tud ie s ,
a t t e n t i o n h a s m a i n l y c o n c e n t r a t e d o n e s t a b l i s h i n g d i -
a g n o s t i c c r it e r i a a n d p r o g n o s t i c f a c t o r s t h a t w o u l d r e l i -
a b l y p r e d i c t a f a v o r a b l e o u t c o m e f o l l o w i n g a v e n t r i c u l a r
s h u n ti n g p ro c e d u r e . 4'6'8'11,22,34,36,53,56,63,64
I n t h is r e p o r t , w e p r e s e n t t h e r e s u lt s o f t r e a t m e n t o f
4 0 p a t ie n t s w i t h t h e s y n d r o m e o f N P H . T h e q u e s t i o n s
w e h a v e a t t e m p t e d t o a n s w e r i n c l u d e : A r e t h e r e a n y
c r i t e r i a o n t h e b a s i s o f w h i c h w e c a n s e l e c t w i t h c e r -
t a i n t y a t le a s t s o m e o f t h e p a t i e n t s w i t h t h e s y n d r o m e ?
A r e t h e re a n y p a t i e n ts w i t h th e s y n d r o m e w h o d o n o t
r e s p o n d f a v o r a b l y t o a s h u n t i n g p r o c e d u r e ? a n d W h y
d o t h e y n o t r e s p o n d ?
C l i n i c a l M a t e r i a l a n d M e t h o d s
T h e s t u d y c o n c e r n s 4 0 p a t i e n t s i n w h o m t h e d i a g -
n o s is o f N P H w a s b as e d o n c l i n ic a l a n d c o m p u t e r i z e d
t o m o g r a p h y ( C T ) c r i t e r i a . A l l t h e p a t i e n t s w e r e h o s p i -
t a l i z e d i n e i t h e r t h e N e u r o s u r g i c a l o r t h e N e u r o l o g i c a l
D e p a r t m e n t s o f t h e A r m y G e n e r a l H o s p i t a l o r t h e
A r m y V e t e r a n s A d m i n i s t r a t io n H o s p i t a l b e t w e e n J a n -
u a r y , 1 9 7 9 , a n d A u g u s t , 1 9 8 3 . F o r t r e a t m e n t a n d i n c l u -
s i o n i n t h e s t u d y , p a t i e n t s m u s t h a v e h a d a c l i n i c a l
h i s t o r y a n d s y m p t o m a t o l o g y s u g g e s t i v e o f t h e s y n -
d r o m e a n d t h e d e m o n s t r a t i o n o f a d i la t e d u n o b s t r u c t e d
v e n t r i c u l a r s y s te m o n t h e C T s c an , t o g e t h e r w i t h s o m e
a d d i t i o n a l f e a t u r e s w h i c h e x c l u d e d d i l a t a ti o n
ex vacuo
o f t h e v e n t r i c u l a r s y s te m . L u m b a r p u n c t u r e w i t h m e a -
s u r e m e n t o f t h e C S F p r e s s u r e w as n o t c o n s i d e r e d n ec -
e s s a r y a n d w a s t h e r e f o r e p e r f o r m e d a c c o r d i n g t o t h e
n e e d s o f e a c h p a t i e n t . A p a r t f r o m r o u t i n e i n v e s t i g a -
t i on s , n o o t h e r t e s ts w e r e p e r f o r m e d b e f o r e t r e a t m e n t
w a s u n d e r t a k e n .
I n t h i s s e r i e s o f p a t i e n t s w e d i d n o t c o n s i d e r s e p a -
r a t in g p a t i e n ts w i t h a k n o w n c a u s e o f t h e i r c o m m u n i -
c a t i n g h y d r o c e p h a l u s f r o m t h o s e w i t h a n u n k n o w n
e t i o l o g y ( i d i o p a t h i c ) . T h e r e a s o n s f o r t h i s a r e d i s -
c u s s e d b e l o w .
Patient Population
A l m o s t h a l f o f t h e p a t i e n t s w e r e s e le c te d f r o m a p o o l
o f p a t i e n t s w i t h o t h e r w i s e u n e x p l a i n e d g a i t d i s tu r b a n c e
a n d d e m e n t i a . T h e r e m a i n d e r w e r e m o s t l y n e u r o su r g i -
c a l p a t i e n t s u n d e r c a r e o r b e i n g f o l l o w e d f o r o t h e r
i n t r a c r a n i a l d i s o r d e rs . T h e r e w e r e 2 4 p a t i e n t s w i t h c o m -
m u n i c a t i n g h y d r o c e p h a l u s o f k n o w n e t i o lo g y , a n d 1 6
i n w h o m n o c a u s e f o r t h e h y d r o c e p h a l u s c o u l d b e
i d e n t i f i e d f r o m e i t h e r t h e i n v e s t i g a t io n s o r t h e p a t i e n t ' s
m e d i c a l h i s to r y , b a s e d o n i n f o r m a t i o n g i v e n m a i n l y b y
the re la t ives (Tab le 1 ).
G a i t d i s t u r b a n c e w a s p r e s e n t i n e v e r y p a ti e n t a n d
r a n g e d f r o m a m i l d d e f i c i t i n b a l a n c e t o c o m p l e t e
i n a b i l i t y t o w a l k o r e v e n s t a n d . E x c l u d i n g t h e f o u r
J. Neurosurg. / Volume 61/September, 1984
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TABLE 1
Clinical eatures in 40 patients with the NPH syndrome*
J . Vass i louth i s
Duration of Urinary
No. of Deteriora- Ga it Dis-
Etiology Cases Age R a n g e S ym pto m s t ioni" Mu tism Dementia Incont i-
(range) turbance nence
SAH 10 20-63 3 wks-10 mos 4 2 6~ 8 7
craniotomy 6 42-64 3 wks-2 yrs 2 0 6 5 2
CNS infection 3 15-58 2 mo s- 1 yr 0 0 3 3 1
head injury 5 58-75 6 mo s-10 yrs 1 1 4:~ 4 3
unknow n (idiopathic) 16 52-80 1-4 yrs 0 0 16 12 6
total cases 40 7 3 35~; 32 19
* NPH = normal-pressurehydrocephalus;SAH = subarachnoid hemorrhage;CNS - - c entral nervous system.
t Deteriorationof preexistingdeficits or failure o make a good recovery.
The remaining patients were bedridden.
p a t i e n t s w i t h s u b a r a c h n o i d h e m o r r h a g e ( S A H ) w h o
w e r e b e d r i d d e n a t d i a g n o si s , in e v e r y i n s t a n c e t h e o n s e t
o f t h e d i s a b i l i t y w a s i n s i d i o u s a n d r e q u i r e d s o m e t i m e
t o b e c o m e a p p a r e n t t o t h e p a t i e n t o r h i s r e la t iv e s . T h i s
p e r i o d o f t i m e w a s s h o r t e r i n t h e g r o u p w i t h k n o w n
e t i o l o g y ( s e v e r a l w e e k s t o 1 y e a r , w i t h o n e e x c e p t i o n )
t h a n i n t h e i d i o p a t h i c g r o u p ( 1 t o 4 y e a r s ) . I n f o u r
p a t i e n t s i n t h e i d i o p a t h i c g r o u p , i n a b i l i t y t o w a l k w a s
t h e o n l y p r e se n t i n g s y m p t o m , s a v e f o r a m i l d m e m o r y
d e f i c it c o n s i d e r e d " n o r m a l " f o r th e p a t i e n t ' s a g e .
F r a n k d e m e n t i a ( a k i n e t i c m u t i s m i n t h r e e ca s e s) w a s
t h e p r e d o m i n a n t f e a t u r e i n e i g ht p a ti e n ts . I m p a i r m e n t
o f m e m o r y , m a i n l y s h o r t - t e r m , s lo w i n g o f t h o u g h t , a n d
l a c k o f a t t e n t i o n o r i n i t i a t i v e w e r e t h e m o s t c o m m o n
f o r m s o f d i s t u r b a n c e i n t h e r e m a i n i n g 2 4 c a s e s. I n f o u r
p a t i en t s t h e d e m e n t i a a n t e d a t e d t h e d i s t u r b a n c e o f g a i t
b y s e v e r a l m o n t h s t o y e a r s ; i n f a c t i t d o m i n a t e d t h e
c l i n i c a l p i c t u r e . O n e o f t h e s e p a t i e n t s h a d s u f f e r e d
s e v e r e i s c h e m i c d a m a g e t o t h e h y p o t h a l a m u s a n d t h e
m e d i a l a s p e c ts o f t h e f r o n t a l l o b e s f o l l o w i n g r u p t u r e o f
a g i a n t a n t e r i o r c o m m u n i c a t i n g a r t e r y a n e u r y s m , a n -
o t h e r h a d a s e v e r e c lo s e d h e a d i n j u r y , r e s i d u a l a p h a s ia ,
h e m i p a r e s i s , a n d p e r s o n a l i t y c h a n g e s , a n d t w o p a t i e n t s
w e r e i n t h e i d i o p a t h i c g r o u p . T h e s e p a t i e n t s a r e d i s -
c u s s e d s e p a r a t e l y , a s t h e y f o r m t h e g r o u p o f " f a i r "
r e s p o n d e r s t o a s h u n t i n g p r o c e d u r e .
U r i n a r y i n c o n t i n e n c e w a s p r e s e n t in a l m o s t h a l f t h e
p a t i e n t s ( 1 9 o u t o f 4 0 ) , a n d i n e v e r y i n s ta n c e i t f o l l o w e d
d i s t u r b an c e o f g a it a n d m e n t a t i o n . M o s t o f t e n it t o o k
t h e f o r m o f l a c k o f c o n c e r n , b u t i n a f e w p a t i e n t s i t
a p p e a r e d a s u r g e n c y o f m i c t u r i t io n .
O t h e r s y m p t o m s o r s i g n s , s u c h a s h e a d a c h e , d i z z i -
n e s s , v i s u a l d i s t u r b a n c e s , o r p y r a m i d a l o r e x t r a p y r a m -
i d a l s ig n s, w e r e l e ss f r e q u e n t a n d a r e n o t c o n s i d e r e d i n
t h i s s t u d y . I n t h r e e p a t i e n t s ( t w o w i t h S A H a n d o n e
w i t h a h i s t o r y o f h e a d i n j u r y ) , t h e d i a g n o s i s o f t h e
s y n d r o m e w a s s u s p e c te d w h e n t h e i r p r e e x is t in g n e u r o -
log ica l de f i c i t s began to de te r io ra te . In te re s t ing ly , the i r
C T s c a n s d e m o n s t r a t e d , i n a d d i t i o n t o v e n t r i c u l a r d i l-
a t a t i o n , t h e p r e s e n c e o f a r e a s o f l o w d e n s i t y r o u g h l y
c o r r e s p o n d i n g t o t h e u n d e r l y i n g i s ch e m i c w h i t e m a t t e r
w h i c h d i s a p p e a r e d f o l l o w i n g t r e a t m e n t . 59 F i n a l l y , f a il -
u r e t o m a k e a s a t i s f a c t o r y r e c o v e r y f o l l o w i n g S A H o r
s u r g e ry f o r i n t r ac r a n i al t u m o r ( m e n i n g i o m a o r p i t u i t a ry
a d e n o m a ) l e d t o t h e c o r r e c t d i a g n o s i s " n f o u r o t h e r
pa t i en t s .
C o m p u t e r i z e d T o m o g r a p h y F i n d i n g s
M o s t o f t h e C T s c a n s w e r e o b t a i n e d o n a n O h i o
N u c l e a r " D e l t a " h e a d s c a n n e r a n d d i s p l ay e d o n a 1 6 0
x 1 6 0 m a t r i x . I n t h e e i g h t m o s t r e c e n t c a s es , a P f i z e r
A S a n d E O 4 5 0 b o d y s c a n n e r w a s a ls o u s ed . * F o u r C T
s c a n c r i t e r i a w e r e u s e d i n t h i s s t u d y , b a s e d o n o u r
p r e v i o u s e x p e r i e n c e6~ a n d t h e e x p e r i e n c e o f o t h -
ers.6.11,21,26,44,48,56T h e s e c r i t e r i a w e r e t h e p r e s e n c e o n t h e
C T s c a n o f : 1 ) d i l a t a t i o n o f t h e u n o b s t r u c t e d v e n t r i c u l a r
s y s t e m ; 2 ) o b l i t e r a t i o n o f t h e c e r e b r a l s u l ci ; 3 ) a re a s o f
p e r i v e n t ri c u l a r l o w d e n s it y ; a n d 4 ) " r o u n d i n g " o f t h e
f r o n t a l h o r n s o f t h e l a t e r a l v e n t r i c l e s . W e c o n s i d e r e d
t h e s e c h a r a c t e r i s t i c s a s i n d i c a t i n g t h a t t h e c o e x i s t i n g
v e n t r i c u l ar e n l a r g e m e n t w a s n o t a n e x v a c u o v a r i a n t .
S u b s e q u e n t l y , o n l y p a t i e n t s s a t i s f y i n g a t l e a s t o n e o f
t h e f i r s t t w o c r i t e r i a , i n a d d i t i o n t o t h e v e n t r i c u l a r
d i l at a ti o n , w e r e o f f e r e d t r e a t m e n t a n d i n c l u d e d i n
t h e s t u d y .
D i l a t a t i o n o f t h e u n o b s t r u c t e d v e n t r i c u l a r s y s t e m
w a s p r e s e n t i n e v e r y p a t i e n t a n d w a s c o n s i d e r e d a
p r e r e q u i s i t e f o r t r e a t m e n t a n d i n c l u s i o n i n t h e s t u d y .
O n l y p a t i e n t s w i t h m o r e t h a n m o d e r a t e v e n t r i c u l a r
e n l a r g e m e n t w e r e s e l e c t e d , i n o r d e r t o o v e r c o m e a r g u -
m e n t s r e g a r d i n g t h e a c t u a l s iz e o f t h e v e n t r ic l e s . 66 T h u s ,
o n l y p a ti e n t s in w h o m t h e r a t io o f t h e w i d t h o f t h e
l a t e ra l v e n t r ic l e s a t t h e l e v el o f t h e f o r a m i n a o f M o n r o
t o t h e t r a n s v e r s e i n n e r d i a m e t e r o f t h e s k u l l a t t h e s a m e
leve l was abo ve 1 :5 were in c lude d . 6~
Obl i t e ra t ion o f the ce rebra l su lc i (F igs . 1 , 2 , and 3 ) ,
a s s e e n in t h e u p p e r m o s t C T c u t s , w a s p r e s e n t i n 3 l
c a s e s ( T a b l e 2 ) ; t h u s , n o p a t i e n t s w e r e e x c l u d e d f r o m
t h e s t u d y o n t h e b a s i s o f t h e a b s e n c e o f t h i s c r i t e r i o n .
* Del ta scanner 25 m anufactured by O hio N uclear , Inc .,
2910 Aurora Road, Solon, Ohio. Pfizer AS and EO450 bo dy
scanne r manu facture d by Pfizer Medical Systems, Inc. , 9052
Annapolis Road, Columbia, Maryland.
5 0 2
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Norm al-pressure hydrocephalus
FIG. 1. The c hief comp uter ized tomog raphy character is t ics in a 70-year-old wo ma n wi th normal -pressure
hydrocephalus syndrom e, a and b: Ma rked vent r icular di la ta tion and "round ing" of the frontal horns of the
lateral ventricles are seen. c: Periven tricular areas of low density are indicated by arrows, d: The cerebral
sulci are obliterated (arrows).
FIG. 2. Obli terat ion of the cerebral sulci
(arrows)
in a 72-year-old ma n with ventricular enlargement. N ote
the considerable d ilatat ion o f the sub arach noid spaces at the low er levels ( including the Sylvian fissures).
FIG. 3.
Left Pair:
Obliterat ion of the cerebral sulci in a 58-year-old man with the normal-pressure
hydr ocephal us syndr om e (smal l arrow). No te the widening o f the Sylvian fissures (large arrow). Rig ht Pair.
Reapp earance of the cerebral sulc i 1 year following t reatm ent (small arrows). No te the diminu t ion in the s ize
of th e Sylvian fissures
(large arrow).
T h e w i d t h o f t h e c e r e b r a l s u l c i a n d i t s p r e d i c t i v e v a l u e
r e g a r d i n g r e s p o n s e t o t r e a t m e n t h a v e b e e n d i s c u s s e d
pr ev io us ly . 6J1'22'26'36'56 I n o u r s t u d y , o b l i t e r a t i o n o f t h e
s u l c i w a s s o m e t i m e s o b s e r v e d i n c o m b i n a t i o n w i t h
d i l a t a t i o n o f t h e s u b a r a c h n o i d s p a c e s a t l o w e r l e v e l s ,
i nc l ud i ng t he S y l v i an f i s su r es ( F i gs . 2 and 3 ) . T h i s
f i n d i n g w a s c o n s i d e r e d t o i n d i c a t e o b s t r u c t i o n o f t h e
s u b a r a c h n o i d s p a c e o f t h e c o n v e x i t y ( T a b l e 2 ). I n a f e w
c a se s , w h i c h w e r e f o l lo w e d p o s t o p e r a t i v e l y w i t h C T
s c a n n i n g , r e a p p e a r a n c e o f t h e c e r e b r a l s u lc i w a s d o c u -
m e n t e d ( F i g . 3 ) , a n d t h e v a l i d i t y o f t h i s c r i t e r i o n w a s
r e i n f o r c e d .
J. Neurosurg . / Volum e 6 1/S epte mb er, 1984
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TABLE 2
Computerized tomography characteristics in 40 patients with the NPH syndrome*
J . Vass i louth i s
> Moderate Obliteration Periventricular
Etiology No. of Cases Ventricular of Cerebral Areas of Low Rounding of Cortical
Enlargement Sulci Density Frontal Horns Atrophy
SAH 10 10 8 (2)? 8 7 1
craniotomy 6 6 4 ( 1)? 5 5 1
CNS infection 3 3 3 3 3 -
head injury 5 5 4 (2)? 3 4 2
unknown (idiopathic) 16 16 12 (4) , 8 9 4
total cases 40 40 31 (9)? 27 28 8
* NPH = normal-pressurehydrocephalus;SAH = subarachnoid hemorrhage;CNS = central nervous system.
t Num bers in parentheses ndicate cases with dilatation of the subarachnoid spaces at lower evels (Sylvianfissures ncluded).
I n o n e S A H p a t i en t , i n o n e h e a d - i n j u r e d p a t ie n t , a n d
i n t w o i n t h e i d i o p a t h i c g r o u p , c e r e b r a l s u l c i w e r e
c l e a r l y v i s ib l e i n t h e u p p e r m o s t c u t s , b u t i n t h e r e m a i n -
i n g c as e s n o f i r m j u d g m e n t c o u l d b e m a d e f o r t e c h n i c a l
r e a s o n s ( i n c l u d i n g m o v e m e n t a r t i f a c t s o r n o a v a i l a b l e
u p p e r m o s t C T c u t s ) . T h e c o m b i n a t i o n o f t h e c l i n i c a l
p i c t u r e a n d t h e p r e s e n c e o f a r e as o f p e r i v e n t ri c u l a r l o w
d e n s i t y i n t h e s e l a s t p a t i e n t s w a s, h o w e v e r , c o n s i d e r e d
s u f f i c i en t f o r i n c l u s i o n o f t h e p a t i e n t s i n t h e s t u d y ( F i g.
4 ) . T h i s f e a t u r e w a s t a k e n t o i n d i c a t e t r a n s e p e n d y m a l
m o v e m e n t a n d a b s o r p t i o n o f C S F , w h i c h i s k n o w n t o
take p lace in co m m un ica t in g hyd roce pha lus . 13'25'3~176
G r a n h o l m 21 h a s s h o w n t h a t p e r i v e n t r i c u l a r a r e a s o f l o w
d e n s i t y a r e p r e s e n t i n c a s e s o f h y d r o c e p h a l u s a n d d i s -
a p p e a r f o l lo w i n g s h u n t i n g . T h i s w a s s u b s e q u e n t l y c o n -
f i rm ed b y o the rs . 43'44 Overa l l , 27 pa t i en t s exh ib i t ed p e r -
i v e n t r i c u l a r lo w - d e n s i t y a r e a s o n C T s c a n n i n g , a n d t h i s
w a s t a k e n a s a n a b s o l u t e i n d i c a t i o n f o r t r e a t m e n t i n
eve ry pa t i en t (F igs . 1 and 4 ) . In te re s t ing ly , th i s fea tu r e
w a s s e e n i n f o u r o f o u r p a t i e n t s w i t h c l e a r l y v i s i b l e
cor t i ca l su lc i (F ig . 4 ), sugges t ing tha t ob l i t e ra t ion o f the
s u b a r a c h n o i d s p a c e i n t h e s e a r e a s i s n o t n e c e s s a r i l y
p r e s e n t i n e v e r y p a t i e n t w i t h th i s s y n d r o m e , a n d t h a t i t
i s a t l e a st p a r t i a ll y d e p e n d e n t o n t h e a c t u a l s i z e o f t h e
ce rebra l gyr i .
F i n a l ly , " r o u n d i n g " o f t h e f r o n t a l h o r n s o f t h e l a t e r a l
v e n t r i c l e s ( F ig . 1 ) w a s d e m o n s t r a t e d i n 2 8 p a t i e n t s a n d
w a s c o n s i d e r e d a s e q u i v a l e n t t o t h e p n e u m o e n c e p h a -
l o g r a p h i c ( P E G ) f i n d i n g t h a t t h e g r e a t e r i m p a c t o f
v e n t r i c u l a r d i l a t a ti o n i s o n t h e a n t e r i o r p o r t i o n s o f t h e
ven t r i cu la r sys tem. 21'37 Th i s fe a tu re d id no t s e rve a s an
a b s o l u t e i n d i c a t i o n f o r t r e a t m e n t i n t h i s s e ri e s.
A n i n t er e s ti n g g r o u p o f e i g h t p at i e nt s , h a l f o f w h o m
w e r e i n t h e i d i o p a t h i c c a t e g o r y , s h o w e d C T f e a t u r e s
s u g g e st i ve o f c o r t i c a l a t r o p h y . T h i s a s a r u l e w a s b e t t e r
s e e n o n C T c u t s l o w e r t h a n t h e u p p e r m o s t o n e s ; f o r
e x a m p l e , c u t s t h r o u g h t h e u p p e r p a r t o f t h e l a t e r a l
v e n t r i c u l a r b o d i e s . N o a t t e m p t w a s m a d e t o d i s ti n g u i s h
t h e s e a p p e a r a n c e s e t i o l o g ic a l ly , as t h i s w a s b e y o n d t h e
s c o p e o f t h i s s t u d y . I t i s e m p h a s i z e d , h o w e v e r , t h a t i n
e v e r y p a t i e n t o f t h is g r o u p t h e c o m b i n a t i o n o f c l in i ca l
a n d a d d i t i o n a l C T s c a n f e a t u r e s s u c h a s t h o s e m e n -
t i o n e d a b o v e s u g g e s t e d t h a t t h e c o e x i s t e n t v e n t r i c u l a r
d i l a t a t i o n w a s a t l e a s t p a r t i a l l y d u e t o o b s t r u c t i o n o f
FIG. 4. Areas of p eriventricular low density
(arrows)
in a 75-year-old patient with ven tricular dilatation 6
mo nths following head injury. Th e cerebral sulci are clearly visible.
5 0 4 J . N e u r os u rg . / V o l u m e 6 1 / S e p t e m b e r , 1 9 8 4
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Norm al-pressure hydrocephalus
the CSF bulk flow, and required shunting. This was
shown to be the case in every patient of this group,
even in the three patients who showed only a fair
response to treatment.
Management
Following diagnosis and routine preoperative inves-
tigations (chest radiograph, electrocardiogram, blood
biochemical analysis, blood count and hematocrit, and
urinalysis), all the patients were given prophylactic flu-
cloxacillin (Floxapen) in a dose of 500 mg three times
daily for 1 day pre- and 2 days postoperatively. Surgery
was performed under general anesthesia. A ventriculo-
peritoneal shunting system was installed in every pa-
tient, incorporating a medium-pressure Holter valve
and a standard Rickham reservoir.t The standard sur-
gical technique was used, with special care taken that
no part of the device came in contact with the patient's
skin. Operative time ranged from 50 to 70 minutes.
Patients were encouraged to leave their bed in the 2nd
postoperative day and were usually discharged home
between the 8th and the 10th day. Follow-up exami-
nation was performed at 3 and 6 months, at 1 year, and
thereafter every year.
R e s u l t s
Response to t reatment was graded according to the
criteria proposed by Black, 6 which are as follows:
Excellent: resumed pre-illness activity without deficit
Good: resumed pre-illness activity with moderate
deficit
Fair: improved but no return to previous work
Poor: no change or worse.
Table 3 summarizes the results o f treatment. Thirty
patients achieved an excellent result. Of the remaining
10, six were judged as good responders in that they
obtained complete resolution of gait disturbance but
not the memory deficit. They were nevertheless able to
return to their previous activities. Four patients showed
only a fair response to treatment. These patients deserve
special mention. The first patient was a 23-year-old
man who suffered two SAH's within 1 month from
rupture of a giant anterior communicating aneurysm.
This was clipped elsewhere. Following surgery, he re-
mained inert and apathetic for a few months and then
began to improve, but reached an unsatisfactory plateau
in 1 year. Memory and emotional dysfunction, together
with mild disturbance of gait, were the predominant
symptoms. There was no urinary incontinence. His CT
scan showed ischemic changes of the medial aspects o f
the frontal lobes, more than moderate ventricular dila-
tation, and areas of periventricular low density. Follow-
ing treatment, he demonstrated definite improvement
t Medium-pressure Holter valve and Rickham reservoir,
supplied by Codman and Shurtleff, Inc., Randolph, Massa-
chusetts.
T A B L E 3
Results of surgery in 40 cases of NPH*
Fol low -U p
Etio logy NO.casesOf Ex cellen t G oo d Fai r Pe rio d (yrs)
SAH 10 9 0 1 1-4
craniotom y 6 5 1 0 1-2
CNS infec t ion 3 3 0 0 1 -4
head injury 5 3 1 1 89
un kn ow n (idiopathic) 16 10 4 2 89189
total cases 40 30 6 4
* N P H = normal-pressure hydrocephalus;SAH = subarachnoid
hemorrhage; CNS = central nervoussystem.
of his gait but no other significant change. ACT scan
6 months following surgery showed disappearance of
the periventricular lucencies but no change in the size
of the ventricles.
The second patient with only fair response was a 73-
year-old man with a severe closed head injury and a
left parietal extradural hematoma. When seen 6 months
after the accident he was mute and bedridden with right
spastic hemiparesis. He was incontinent of urine and
feces. A C T scan showed ventricular dilatation with
periventricular lucencies and visible cerebral sulci (Fig.
4). A few days following surgery he began to converse
and take a few steps with support, but 6 months after
surgery he remains dysphasic with right hemiparesis,
and at times he is incontinent of urine. The third
patient was a 72-year-old man, who presented with a 3-
year history of gait disturbance leading to inability to
walk or stand and frank dementia of 2 years' duration.
He was also incontinent of urine. A CT scan demon-
strated some cortical atrophy, ventricular enlargement,
and definite obliteration of the cerebral sulci, together
with dilatation of the subarachnoid spaces at lower
levels (Fig. 2). One year after surgery, this patient walks
normally; he is continent of urine but continues to have
severe memory deficit.
The last patient in this group, a 73-year-old man,
was referred with a history of gait disturbance of 10
months' duration and a longer history of short-term
memory deficit and mild dementia. His medical history
included coronary artery bypass surgery for myocardial
ischemia and two mild ischemic strokes of the right
cerebral hemisphere. ACT scan showed ischemic le-
sions and cortical atrophy in both hemispheres and
ventricular dilatation combined with obliteration of the
cerebral sulci. Soon after surgery he was able to walk
almost normally (and he remains able to do so); how-
ever, his dementia remains unchanged 6 months post-
operatively.
There were four additional patients (two with SAH
and two in the idiopathic group) who showed an ini tial
satisfactory response to surgery only to return to their
preoperative level in 1 to 2 days. In every instance,
palpation of the valve showed that it emptied and filled
J. Neurosurg. / Volume 61 /September, 1984 505
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properly, and the patients' postoperative CT scans
showed no change in the size of the ventricles and no
additional features. Pumping of the valve was then
started three times daily (30 pumpings each time) as
inadequate function of the system was suspected. This
produced a definite improvement in the patients' con-
dition within 48 hours. Improvement was dramatic in
two cases. Eventually, three of these patients achieved
an excellent and one a good response to treatment.
Pumping, performed by instructed relatives, was suc-
cessfully discontinued in two patients in 3 months, and
is continuing in the rest (6 months and 1 year later,
respectively).
There was one postoperative death in this series. This
was in an 80-year-old man with a 4-year history of gait
disturbance leading to inability to stand or walk; he had
no other symptoms. He responded dramatically to the
shunting procedure, and was able to walk on the 3rd
postoperative day. He was discharged home on the 9th
postoperative day, but died from bronchopneumonia
in another hospital 5 weeks later.
Obstruction of the proximal end of the shunt system
was diagnosed in one patient and the ventricular cath-
eter was revised. Four patients developed postoperative
urinary tract infections or bronchopneumonia, and
were treated successfully with the appropriate antibiot-
ics. There were no cases of shunt infection or postop-
erative subdural hematomas.
D iscuss ion
Eighteen years since its initial description, 2,27 the
syndrome of normal-pressure hydrocephalus continues
to present quest ions, mainly regarding reliable diagnos-
tic criteria and prognostic factors associated with a
shunting procedure. 6'22'36'53'56 There is little disagree-
ment about the clinical symptoms that constitute
the syndrome. Disturbance of gait, dementia, and uri-
nary incontinence are regarded as the predominant
signs. 1,21627 The demonstration o f a dilated ventricular
system on neuroradiological studies is the cardinal fea-
ture, but it is now well appreciated that the CSF pressure
is not normal in these patients, at least not continu-
ously.9.~1.22,28,48,54,55 The demonstrat ion of a definite and
at times dramatic improvement of a patient's symp-
toms following a shunting procedure 1'2'27'46 has stimu-
lated tremendous interest in this treatable cause of
dementia. ~0
The initial enthusiasm5~ has gradually subsided, leav-
ing behind a voluminous amount of information. Nu-
merous studies dealing with the syndrome and propos-
ing criteria for selection of patients appropriate for
treatment have appeared in the literature. These include
PEG
fe a t u re s , 23 '24 '36 '37 '56 '58 '64
iodine- 13 I-labeled human
serum albumin (RIHSA) scanning patterns following
intrathecal administration, 329375658 lumbar45'48 or ven-
triculolumbar38 subarachnoid infusion tests, and eval-
uation of the patients' mental function before and after
withdrawal of small amounts of
C SF. 1 7 ' 6 3
Measure-
J . Vass i louth i s
ments of cerebral blood ~]OW, 9 CT features, 6"I1"22'26"36
and patterns of continuously measured and recorded
intracranial pressure (ICP) 91122 28485455 have been pro-
posed as predictors of a response to treatment. It is
generally agreed that continuous ICP monitoring offers
one of the most reliable means for selection of patients
likely to respond to treatment.48 Since the pioneering
work of Symon, et al. , 55 many other investigators have
demonstrated that the ICP in these patients is not
normal, thus refuting the title of the syndrome. They
also showed that the presence in the record of the so-
called B-waves is of important prognostic signifi-
cance.T M More recently, B0rgesen, e t aL , 8 found
that measurement of the conductance to outflow of the
CSF is more useful in predicting the ou tcome to treat-
ment than measurement of the ICP.
Obstruction of the bulk flow of the CSF in the
subarachnoid space distal to the outlet foramina of the
fourth ventricle has been proposed as the initial defect
in this syndrome. This eventually leads to ventricular
dilatation, which is responsible for the clinical pic-
ture.
2"23'27'38
Several pathoanatomical reports have
substantiated this proposition, demonstrating lepto-
meningeal fibrosis mainly in the basal cisterns or the
subarachnoid space of the convexities of the hemi-
spheres with or without changes of the arachnoid gran-
ulations in patients with known etiology (SAH, central
nervous system infection, head trauma, intracranial
surgery) or unknown (idiopathic) cause of thei r hydro-
cephalus. 121329495~ Additional findings include ven-
tricular ependymal disruption, periventricular white
matter edema, subependymal glial reaction, and peri-
ventricular loss of myelin staining, 13 features that are
considered to be caused by disturbance of the CSF flow
and ventricular enlargement. As transependymal and
possibly transchoroidal absorption of CSF is en-
hanced,4~ the initial intracranial hypertension sub-
sides but the ventricles continue to enlarge, leading to
destruction o f periventricular nerve fibers. 61 How ven-
tricular enlargement continues in the presence of a fall
in CSF pressure is difficult to explain. Hakim and
Adams27 offered the proposition that, since the total
force on the ventricular wall is related to both area and
pressure, if the area of the ventricles is increased, a
smaller pressure is required to maintain their dilated
state. This theory has since been taken further by other
authorsJ 5'2~ It is also interest ing to note that experi-
mental obliteration of the subarachnoid space leads to
ipsilateral ventricular dilatation,25 which lends support
to the proposition that obliteration of the subarachnoid
space of the convexities contributes to an increase in
cerebral mantle pressure between the ventricles and the
subdural space. 253~
It is well known that some patients are found at
postmortem examination to have changes due to both
Alzheimer's disease and leptomeningeal fibrosis, caus-
ing obstruction of the subarachnoid space. 13 Postmor-
tem studies o f patients with the NPH syndrome show-
ing extensive hypertensive cerebrovascular disease with
506
J . N e u r os u r g. / V o l u m e 6 1 / S e p t e m b e r , 1 9 8 4
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Norm al-pressure hydrocephalus
m u l t i p l e s m a l l i n fa r c t s b u t w i t h o u t g r o ss l e p t o m e n i n -
gea l changes sh ou ld be v i ewed wi th c au t ion ; w e l l-o rga -
n i z e d s u b d u r a l m e m b r a n e s w e r e p r e s e n t i n t w o o f t h e
t h r e e r e p o r t e d c as e s a n d i n t h e t h i r d t h e d i a g n o s i s o f
t h e s y n d r o m e w a s n o t certain. 14'35
In c l i n i ca l p rac t i ce , wh en a pa t i en t p re sen t s wi th ga i t
d i s t u r b a n c e a n d m e m o r y d e f i c i t ( w i t h o r w i t h o u t u r i -
n a r y i n c o n t i n e n c e ) , a d e c i s i o n m u s t b e m a d e w h e t h e r
a rad io log ica l ly dem ons t ra t ed v en t r i cu l a r d i l a t a t i on i s
c l i n i ca lly s ign i f i can t and the re fore requ i re s s hun t ing , o r
whe the r i t i s on ly t he re su l t o f was t ing o f ce rebra l
subs t ance (d i l a t a t i on e x v a c u o ) . T h e e x i s t i n g b o d y o f
ev idence does no t o f fe r r e l i ab l e c r i t e r i a on which to
base wi th ce r t a in ty t he d i s t i nc t ion be tween these en t i -
t ies.6'7'48 T h e b a s i c q u e s t i o n r e m a i n s : D o a n y c a s e s o f
N P H s y n d r o m e n o t r e s p o n d t o t r e a tm e n t ? A n d i f, ye s,
W h y d o t h e y n o t r e s p o n d ? A l m o s t a l l i n v e s t i g a t i v e
e f fo r t s h a v e b e e n c o n c e n t r a t e d i n " i d e n t i f y i n g t h e w i n -
ne rs ; " t ha t i s , t he pa t i en t s who wi l l r e spond favorab ly
to a s hun t ing p rocedure . I~ As a re su l t , conc lus ions hav e
b e e n b a s e d o n t h e r e s p o n s e t o t r e a t m e n t o f g r o u p s o f
pa t i en t s wi th v en t r i cu l a r d i l a t a t i o n fu l f i ll i ng va r ious
c r i te r i a . The va l id i t y o f t hese c r i t e r i a was subsequ en t ly
eva lua t ed in re t rospec t accord ing to t he obse rved re -
s p o n s e o f t h e p a t i e n t t o t h e s h u n t i n g p r o c e d u r e . I t i s
obv ious t ha t i n t h i s p rocess two va r i ab l e s a re a t work .
F i r s t , t he c l i n i ca l ma te r i a l m ay no t be pure . I t is i nev i-
t a b le t h a t s o m e p a t i e n ts w i t h d i l a t a t i o n e x v a c u o a n d /
o r s o m e w i t h b o t h t h e s y n d r o m e a n d a d d i t i o n a l ce r e br a l
pa tho logy ( such a s Alzhe imer ' s d i sease ) e scape recog-
n i t i on and a re i nc luded in t he s tud i e s . These cases
s h o u l d n o t h a v e b e e n i n c l u d e d i n t h e e v a l u a t i o n p r o c es s
b e c a u s e i f t h e y h a d b e e n r e c o g n i z e d a t t h e b e g i n n i n g
t h e y w o u l d n o t h a v e b e e n t r e a t e d b y s h u n t in g . T h e
second fac to r i nvo lved the e f fec t iveness o f t r ea tment .
I n m o s t o f t h e s t u d ie s , th i s w a s j u d g e d o n t h e s u p p o s i -
t i o n t h a t a p r o p e r l y s e le c te d a n d a d e q u a t e l y f u n c t i o n i n g
shunt sys t em had been ins t a l l ed . I t i s su rpr i s ing how
f e w s tu d i e s h a v e a d d r e s s e d t h e q u e s t i o n o f e v a l u a t i o n
o f s h u n t f u n c t i o n , p a r t i c u la r l y i n c a s e s o f i d i o p a t h ic
N PH tha t fa i led to resp on d to t rea tm ent . 4'36'56'65
S e p a r a t i o n o f t h e g r o u p o f p a t i e n t s w i t h N P H o f
u n k n o w n e t i o l o g y ( i d io p a t h i c g r o u p ) b y m a n y a u -
thors 6'22'26'32'59 f r o m t h o s e w i t h k n o w n c a u s e, a s i f d i f-
f e r e n t p a t h o lo g i c a l m e c h a n i s m s a r e i n v o l v e d i n t h e t w o
g r o u p s , h as n o t i n o u r o p i n i o n c o n t r i b u t e d t o t h e c l ar -
i f i ca t ion o f t he i ssues . I f t he re a re d i f fe ren t mecha n i sm s
i n v o lv e d , t h e n w e m u s t a c c e p t t h a t w e a r e d e a l i n g w i t h
d i f fe ren t en ti t ie s . In t h i s r e spec t, i t i s o f i n t e re s t t o n o t e
t h e r e s u l t s o f a r e c e n t s t u d y w h i c h s h o w e d s i m i l a r
p a t t e r n s o f I C P r e c o r d i n g s i n t w o g r o u p s o f h y d r o c e -
p h a l ic p a t ie n t s , o n e w i t h k n o w n e t i o l o g y a n d a n o t h e r
of t he i d iop a th i c t ype . 11 I t cou ld , o f course , be c l a ime d
tha t pa t i en t s o f t he f i r s t g roup , a s a ru l e , r e spond
favorab ly t o t r ea tm ent , 56 and th i s i s no t so i n t he
id iopa th i c g roup . I t i s , however , a l so t rue t ha t t he
d i a g n o si s o f t h e s y n d r o m e i s u s u a l ly c e r ta i n f r o m t h e
m e d i c a l h i s to r y i n t h e f i rs t g ro u p a n d , w h e n r e s p o n s e
to t r ea tment i s no t sa t i s fac to ry , a v igorous sea rch fo r
the poss ib l e f ac to r s fo l l ows . Th i s usua l ly i den t i f i e s an
i n a d e q u a t e l y f u n c t i o n i n g s h u n t , w h i c h i s s u b s e q u e n t l y
revised.
I n o u r s t u d y w e a t t e m p t e d t o i n v e s t i g at e th e p o s s i -
b i l i t y o f us ing re l a t i ve ly s imple c r i t e r i a a s a bas i s fo r
d i a g n o s i n g t h e N P H s y n d r o m e , a v o i d i n g in v a s i v e t e c h -
n iques . The c l i n i ca l c r i t e r i a used a re i n acco rdance w i th
t h o s e r e p o r t e d previously. 6'16'22'24'36'47'53'56G a i t d i s t u rb -
ance was p re sen t i n eve ry pa t i en t ( t ha t i s , no pa t i en t
w i t h o u t t h i s s y m p t o m w a s c o n s i d e r e d f o r t r e a t m e n t ) .
As a ru l e , ga i t d i s tu rbance he ra lded the o the r symp-
toms , 16,18 and imp rov ed in eve ry p a t i en t fo l l owing t r ea t -
m e n t . D e m e n t i a w a s t h e d o m i n a n t s y m p t o m i n e i g h t
p a t i e n ts a n d w a s p r e s e n t i n 3 2 . F o l l o w i n g t r e a t m e n t i t
de f in i t e ly imp rov ed in 22 p a t i en t s , was s l i gh t ly ame l io -
r a t e d i n s i x, a n d r e m a i n e d u n c h a n g e d i n f o u r ( a ll c as e s
w i t h u n d e r l y i n g a d d i t i o n a l c e r eb r a l p a t h o lo g y ) . U r i n a r y
incon t inence , w hen p re sen t , r e so lved fo l lowing t r ea t -
m e n t . T h e s e l e c t i o n o f C T s c a n c r i t e r i a w a s b a s e d o n
publ i shed ev idence ,6'11.22.26.36,44,60 a n d o n th e b e li e f th a t
t h e C T s c a n a p p e a r a n c e w o u l d r e p r e s e n t e x is t in g p a t h -
o a n a t o m i c a l c h a n g e s , a s r e p o r t e d b y p r e v i o u s i n -
vestigators.12'13"25'29'49'50'57
The c r i t e r i a used in t h i s s tudy can be c r i t i c i zed a s
s t r ic t . Howev er , cons id e r ing the fac t t ha t a l l t he pa t i en t s
d i a g n o s e d a s s u ff e r in g f r o m t h e N P H s y n d r o m e o n t h e
bas i s o f t hese c r i t e r i a r e spo nded fav orab ly to shun t ing ,
we con c lude th a t t h ey a re a t l ea s t va l id i n se l ec ting wi th
c e r t a i n t y p a t i e n t s w h o d o h a v e t h e s y n d r o m e . O u r
sugges t ed ind i ca t ions fo r t r ea tment a re g iven , and the
o p p o r t u n i t y to s t u d y t h e r e sp o n s e to t h e m i n a h o m o -
geneou s g roup i s o f fe red .
W i t h r e g a r d t o t r e a t m e n t , w e u s e d a m e d i u m - p r e s -
sure va lve sys t em in a l l pa t i en t s i n an a t t empt t o avo id
t h e d e v e l o p m e n t o f s u b d u r a l h e m a t o m a s , w h i c h a r e
m o r e c o m m o n w h e n l o w - p re s su r e s ys t em s
a r e
us ed . 33
W e a ls o u s e d t h e s a m e s y s t e m t o s t a n d a r d i z e t r e a t m e n t
t h r o u g h o u t t h e s e rie s. T h e f i n d i n g t h a t f o u r o f t h e
p a t i e n ts e v e n t u a l l y r e q u i re d p u m p i n g o f t h e i r v a lv e s in
orde r t o ach ieve and ma in t a in a sa t i s fac to ry re su l t
impl i e s t ha t i n t hese cases a l ow-pressure o r h igh- f low
sys t em was p robab ly requ i red . I t a l so sugges t s t ha t i n
t h e s e p a t i e n t s e v e r y e f f o r t s h o u l d b e u n d e r t a k e n t o
a s s u r e a d e q u a t e f u n c t i o n o f t h e s h u n t i n g s y s t e m b e f o r e
fa i l u re o f t he t r ea tment i s accep ted .
F o u r p a t i e n t s s h o w e d a " f a i r " re s p o n s e to t r e a t m e n t
i n t h a t t h e y o n l y a c h i e v e d i m p r o v e m e n t o f g a i t d i s tu r b -
ance . We be l i eve tha t t hese pa t i en t s r epre sen t exam ples
o f c a s es w h e re t h e N P H s y n d r o m e i s s u p e r im p o s e d o n
preex i s t i ng ce rebra l pa tho logy ( i schemia , t r auma , pos-
s ib l e Alzhe imer ' s d i sease , and mul t i - i n fa rc t dement i a ,
respe ctively ). ~1'~9'36'56 Su rgica l tre at m en t is on ly ex-
p e c t e d t o a l l ev i a te s y m p t o m s c a u s e d b y t h e N P H s y n -
d r o m e w i t h o u t i n f l u e n c i n g t h e u n d e r l y i n g p a t h o l o g y ,
a n d i n o u r o p i n i o n t h i s i s w h a t o c c u r r e d i n t h e s e
p a t i e n t s . T h u s , t h e s e c o n d c o n c l u s i o n t h a t e m e r g e s
f r o m t h i s s t u d y i s t h a t a l l p a t i e n t s w i t h th e N P H s y n -
d r o m e r e s p o n d o r s h o u l d r e s p o n d t o t h e p l a c e m e n t o f
a n a d e q u a t e l y f u n c t i o n i n g s h u n t i n g d e v i c e .
J . N e u ro s u rg . / V o l u m e 6 1 / S e p t e m b e r , 1 9 8 4
507
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T h i s s t u d y s u g g e s t s t h a t i t i s p o s s i b l e t o b a s e t h e
d i a g n o si s o f t h e s y n d r o m e o f N P H o n c l i ni c al a n d C T
c r i t e r i a . F a v o r a b l e r e s p o n s e t o t r e a t m e n t i n p a t i e n t s s o
s e l e c t e d c a n b e o b t a i n e d w i t h o u t u n a c c e p t a b l y h i g h
m o r t a l i t y o r m o r b i d i t y r a t e s.
Addendum
S i n c e s u b m i s s i o n o f t h i s m a n u s c r i p t , a r e l e v a n t r e -
p o r t h a s a p p e a r e d ( S al ib i N A , L o u r i e G L , L o u r i e H : A
v a r i a n t o f n o r m a l - p r e s s u r e h y d r o c e p h a l u s s i m u l a t i n g
P i c k ' s d i s e a s e o n c o m p u t e r i z e d t o m o g r a p h y . R e p o r t o f
t wo cases .
J N eu r o s u r g 5 9 : 9 0 2 - 9 0 4 ,
1983) . I n t h i s
p a p e r , d i l a t a t i o n o f t h e S y l v i a n f i ss u r e s, m i m i c k i n g
a t r o p h y o f P i c k ' s d i s e a s e , w a s s h o w n t o b e a f e a t u r e i n
t w o c a s e s o f t h e N P H s y n d r o m e , b o t h o f w h i c h r e -
s p o n d e d f a v o r a b l y to s h u n t i n g .
References
1. Adams RD: Fur ther observat ions of normal pressure
hydrocephalus. Pro c R Soc M ed 59:1135-1140, 1966
2 . Adams R D, F i she r C M, Hak i m S , e t a l : S ympt omat i c
occul t hydroceph alus wi th "nor ma l" cerebrospinal f luid
pressure . A t reatable syndrome. N Engl J Med 273:
117-126, 1965
3. Bannister R, Gilford E, Koc en R: Isotop e encephalogra-
phy i n t he d i agnosi s o f dement i a due t o com muni ca t i ng
hydrocephalus. Lancet 2:1014-1017, 1967
4. Belloni G, di R occo C , Focacci C, et al : Surgical indica-
t ions in normotensive hydrocephalus. A retrospective
analysis of the relat ions of some diagnostic findings to
the results of surgical treatment. Acta Neurnchir 33:
1-21, 1976
5. Benson DF , LeM ay M, Pat ten D H, e t a l: Diagnosis of
normal -pressure hydrocephalus . N Eng l J M ed 283:
609-615, 1970
6. Black PM: Idiopathic normal-pressure hydrocephalus.
Results of shunting in 62 patients. J
Neurosurg
52:
371-377, 1980
7. Black PM: Norm al -pressure hydrocephalus . Current un -
derstanding of diagnostic tests and shunting.
Postgrad
Med
71(2):57-67, 1982
8. B0rgesen SE, Gjerris F, Sorensen SC: Intrac ranial pressure
and conductance to out f low of cerebrospinal f luid in
no rm al pressure hydrocephalus. J N eurosu rg 50:489-493,
1979
9. Chaw la JC, Hu lme A, Coo per R: Int racranial pressure in
pa t i en t s w i th d ement i a and comm uni ca t i ng hydr ocepha -
lus. J N euros urg 40:376-380, 1974
10. Com mu nicat ing hydrocephalus . Lancet 2:1011-1012,
1977 (Editorial)
I 1 . C rockard HA, H anlon K, Du da EE, e t a l : Hydro cephalus
as a cause of dement ia : evaluat ion by computer i sed to-
mo graph y and int racranial pressure m oni tor ing. J N eurol
Neurosurg Psychiatry
40:736-740, 1977
12. DeL and FH, Ja me s AE Jr , Ladd D J , e t a l: Norm al pres-
sure hydrocephalus: a histologic study. Am J Clin Pathol
58:58-63, 1972
13. Di Rocco C, Di Trapani G, Mai ra G, e t a l : Anatomo-
clinical correlat ions in no rmo tensiv e hydrocephalus. Re-
ports on three cases. J Neu rol Sci 33:437-452, 1977
14. Earnes t MP, Fahn S , Karp JH, e t a l : Normal pressure
hydroceph alus and hyper tens ive cerebrovascular disease .
Arch Neu roi 31:262-266, 1974
J . Vass i lou th i s
15. Epstein CM: Th e distribution of intracra nial forces in
acute and chronic hydrocephalus. J Neurol Sci 21:
171-180, 1974
16. Fisher CM : Th e cl inical picture in oc cult hydrocephalus.
Clin Neu rosurg 24:270-284, 1977
17. Fisher CM : Co mm unic ating hydrocephalus. La nce t 1:37,
1978 (Letter)
18. F isher CM: Hyd rocephalus as a cause of di s turbances of
gait in the elderly. Neurology 32:1358-1363, 1982
19. Fisher CM: Lacunar strokes and infarcts: a review. Neu-
rology 32:871-876, 1982
20. Geschwind N: The mec hanism of norma l pressure hyd ro-
cephalus. J N euro l Sci 7:481-493, 1968
21. Granholm L: An explanat ion of the revers ible memory
defect in hydrocephalus, in Beks JW F, Bosch DA, Bro ck
M (eds) : Int racranial Pressure I l l . Ber l in/Heidelbe rg/
New York: Springer-Verlag, 1976, pp 173-176
22. Greenb erg JO, Shenkin HA, Adam R : Idiopathic normal
pressure hydrocephalus -- a report of 73 patients. J
Neurol Neurosurg
Psy chia try 40:336-341, 1977
23. Grei tz T , Grepe A: Encephalography in the diagnosis of
convexi ty block hydrocephalus. Acta Radiol (Diagn)
11:232-242, 1971
24. Guidet t i B , Gagl iardi FM: No rma l pressure hy droceph a-
lus. Acta Neurochi r 27:1-9, 1972
25. Gu inane JE: Wh y does hydrocephalus progress? J
Neurol
Sci 32:1-8, 1977
26. Gunasekera L , Richardson AE: Computer ized axia l to-
mography in idiopathic hydrocephalus .
Brain 100:
749-754, 1977
27. Hakim S , Adams RD: The specia l c l inical problem of
symptomat ic hydrocephalus wi th normal cerebrospinal
fluid pressure. O bserv ations on cerebrospinal f luid hyd ro-
dyn am ics. J N eurol Sci 2:307-327, 1965
28. Ha r tm ann A, Alber ti E : Di f ferent ia t ion of com mu nicat -
ing hydrocephalus and preseni le d eme nt ia by cont inuou s
recording of cerebrospinal fluid pressure. J
Neurol
N e w
rosurg Psychiatry
40:630-640, 1977
29. Heinz ER, Davis DO, Karp HR: Abnormal i sotope c i s -
ternography in sym ptom at ic occult hydrocephalus. A cor-
relative isotopic-neuroradiolog ical stud y in 130 subjects.
Radiology 95:109-120, 1970
30. Hi rat suka H, Ta bata H, Tsu ruoka S , e t a l : Evaluat ion of
per ivent r icular hypoden si ty in exp er imental hydroceph a-
lus by met r izam ide CT ventr iculography. J
Neurosurg
56:235-240, 1982
31. Ho ff J , Barber R: Transcerebral mant le pressure in no r-
mal pressure hydrocephalus. Arch Neurol 31:101-105,
1974
32. Hu ghes CP, Siegel BA, Coxe WS, et al : Ad ult idiopathic
comm uni ca t i ng hydr ocepha l us w it h and w i t hou t shun t -
ing. J Neurnl
Neurosurg Psychiatry
41:961-971, 1978
33. I l l ingworth RD, Logue V, Symon L, et al : The ventricu-
loatrial shunt in the treatment of adult hydrocephalus.
Results and com plication s in 101 patients. J
Neurosurg
35:681-685, 1971
34. Jacobs L , Cont i D, Kinkel WR , e t a l : "No rmal -pressu re"
hydrocephalus. Relat ionship of cl inical and radiographic
f indings to imp rove me nt fol lowing shunt surgery. JA M A
235:510-512, 1976
35. Koto A, Rosenberg G , Zingesser LH, e t a l: Syndrom e of
normal pressure hydrocephalus: possible relat ion to hy-
pertensive and arteriosclerotic vascu lopathy. J Neurol
Neurosurg Psychiatry
40:73-79, 1977
36. Law s ER Jr, Mo kri B: Occ ult hydrocephalus: results of
shunting correlated with diagnostic tests. Clin Neurosurg
24:316-333, 1977
37. LeM ay M, New PFJ: Radiological diagnosis o f occult
5 0 8
J. Neurosurg. / Volume 61/S epte mb er, 1984
-
8/9/2019 The Syndrome of Normal-pressure Hydrocephalus Vassilioutis
9/9
Normal-pressurehydrocephalus
normal-pressure hydrocephalus. Radinlogy 96:347-358,
1970
38. Lore nzo AV, Bresnan M J, Barlow CF: Cerebrospinal f luid
absorption defici t in normal pressure hydrocephalus.
Arch Neu rol 30:387-393, 1974
39 . Mat hew NT , Meyer JS , Har t mann A , e t a l : Abnor ma l
cerebrospinal f luid-blood flow dynam ics. Implica tions in
diagnosis, t reatment, and prognosis in normal pressure
hydrocephalus. Arch Neu rol 32:657-664, 1975
40. M cCo mb JG: Recent research into the nature of cerebro-
spinal f luid format ion and abso rpt ion. J Neurosurg
59:369-383, 1983
41. Messer t B, Wannamaker BB: Reappraisal of the adul t
occult hydrocephalus synd rom e. Neu rology 24:224-231,
1974
42. Mi lhorat TH: Th e thi rd c i rcula tion revisi ted. J Neurosurg
42:628-645, 1975
43. Mori K, Murata T , Nakano Y, e t a l : Per ivent r icular
lucency in hydrocephalus on computer ized tomography.
Surg Neuroi 8:337-340, 1977
44. Moseley IF, Radii EW: Factors influencing the develop-
ment of periventricular lucencies in patients with raised
intracranial pressure. Neuro radiology 17:65-69, 1979
45. Nelson JR, Goodman SJ: An evaluat ion of the cerebro-
spinal f luid infusion test for hydrocephalus. Neurology
21:1037-1053, 1971
46. Ojem ann RG : Norm al pressure hydrocephalus. Cl in Neu-
rosurg 18:337-370, 1971
47. Ojemann RG, F isher CM, Adams RD, e t a l : Fur ther
exper ience wi th the syndrome of "normal" pressure hy-
drocephalus. J Neu rosurg 31:279-294, 1969
48. P ickard JD: Adul t com mu nicat ing hydrocephalus. Br J
Hos p Me d 27:35-44, 1982
49. R ibadeau -Dum as JL , Ricou P , Verdure L , e t a l: E tude
anatom ique d 'un cas d 'hydro crphal ie h press ion norma le .
Neurochirurgie22:138-145, 1976
50. Russel l D: Observat ions on the Pathology of Hyd roceph -
alus. London: Her Majesty's Stat ionery Office, 1949
51. Salmon JH, Armi tage JL: Surgical t reatment of hydro-
cephalus
ex-vacuo.
Ventriculoatrial shu nt for degenera-
t ive brain disease. Neurology 18:1223-1226, 1968
52. Shenkin HA , Greenberg JO, Grossm an CB: Vent r icular
size after shunting for idiopathic normal pressure hydro-
cephalus. J Neurol Ne urosurg Psy chiat ry 38:833-837,
1975
53. Stein SC, Langfit t TW: No rma l-pressu re hydrocephalus.
Predicting the results of cerebrospinal fluid shunting. J
Neu rosnrg 41:463-470, 1974
54. Symon L, Dorsch NWC: Use of long- term int racranial
pressure mea sure me nt to assess hydrocephalic patients
prio r to shunt surgery. J N eurnsu rg 42:258-273, 1975
55. Sym on L, Dorsch NW C, S tephens ILl : Pressure waves
in so-called low-pressure hydrocephalus. Lancet 2:
1291-1292, 1972
56. Symon L, Hinzpeter T : The enigma of normal pressure
hydrocephalus: tests to select patients for surgery and to
predict shu nt function. Clin Neu rosurg 24:285-315, 1977
57 . S ype r t GW , L ef f man H , O j emann GA: Occu l t no r ma l
pressure hydrocephalus mani fes ted by parkinsonism-de-
men t ia comp lex. Neurology 23:234-238, 1973
58. Tator CH, Murray SA: A cl inical , pneumoencephalo-
graphic and radioisotopic s tudy of no rmal -pressure com-
mun icat ing hydrocephalus . Can Med Assnc J 1 05:
573-579, 1971
59. Vassilouthis J: Cerebrospinal f luid edema. J Neurosurg
58:625-6 26, 1983 (Letter)
60. Vassilouthis J, Rich ardso n AE: Ven tricular di latat ion a nd
communicat ing hydrocephalus fol lowing spontaneous
subarachnoid hemorrhage. J Neurosurg 51:341-351,
1979
61. Weller RO, Shulm an K : Infanti le hydrocephalus: cl inical,
histological , and ultrastructural study of brain damage. J
Neurosurg
36:255-265, 1972
62. Whi te DN, Wilson KC, Curry GR, e t a l : The l imi ta t ion
of pulsati le f low through the aqueduct of Sylvius as a
cause of hydrocephalus. J Neurol Sci 42:11-5 l , 1979
63. Wikkels0 C, Andersson H, Blomst rand C, e t a l : The
cl inical ef fect of lumbar puncture in normal pressure
hydrocephalus . J Neurnl Neurosurg Psych iat ry 45:64-69,
1982
64. Wo od JH, Bar t le t D, Jam es AE Jr, e t a l: Normal -pressure
hydrocephalus: d iagnosis and p atient selection for shu nt
surgery. Neurology 24:517-526, 1974
65. Woodford J , Saunders RL, Sachs E Jr : Shunt sys tem
patency tes t ing by lumbar infus ion. J Neurosurg 45:
60-65, 1976
66. W yper DJ, P ickard JD, Matheson M : Accuracy o f ven-
t r icular volum e es t imat ion. J N eurol Neurosurg Psychia-
try 42:345-350, 1979
Man uscr ipt received De cem ber 5, 1983.
Accepted in final form March 26, 1984.
Address reprint requests to:
John Vassilouthis, M.D.,
8 Alopekis Street , Kolo nak i, Athens, Greece.