Sep 26, 1994 - Key words [3-Amyloid precursor protein 9 Head injury -. Diffuse axonal .... axonal injury was present in 8 of the 25 head injury cases; although ...
Acta Neuropathol (1995) 89 : 537-543
9 Springer-Verlag 1995
S. M. Gentleman 9 G. W. Roberts 9T. A. Gennarelli W. L. Maxwell 9 J. H. Adams 9 S. Kerr 9D. I. Graham
Axonal injury: a universal consequence of fatal closed head injury?
Received: 26 September 1994 / Revised, accepted: 23 January 1995
A b s t r a c t ~-Amyloid precursor protein immunostaining has recently been shown to be a reliable method for detecting the damage to axons associated with fatal head injury. In an attempt to compare the efficacy of this technique with conventional histological detection of axonal damage, we have reanalysed sections from a large wellcharacterised series of head-injured and control patients. The results indicate that the frequency of axonal injury has been vastly underestimated using conventional silver techniques, and that axonal injury may in fact be an almost universal consequence of fatal head injury. Key words [3-Amyloid precursor protein 9 Head injury Diffuse axonal injury 9 Immunocytochemistry 9 Diagnosis
Introduction Clinical studies have shown that immediate prolonged unconsciousness which is not associated with an intracranial mass lesion, and is thus diffuse head injury, occurs in almost 50% of patients with severe head injury and is a
S. M. Gentleman (t~) Departments of Psychiatry and Anatomy, Charing Cross and Westminster Medical School, St Dunstan's Road, London W6 8RP, UK Tel.: 44-181-846-7680; Fax: 44-181-846-7025 G. W. Roberts Division of Molecular Neuropathology, Smith Beecham Pharmaceuticals, Harlow, Essex, UK T. A. Gennarelli Division of Neurosurgery, Hospital of University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA W. L. Maxwell Department of Anatomy, University of Glasgow, Glasgow, UK J. H. Adams - S. Kerr 9D. I. Graham University Department of Neuropathology, Institute of Neurological Sciences, Southern General Hospital, Glasgow G51 4TF, UK
cause of some 35% of all deaths from head injury [9, 11]. Although there are various forms of diffuse brain damage, it appears that in many patients some axonal damage is sustained at the moment of injury. Previous studies have emphasised the amount of irreversible damage [2], whereas now there is an increasing appreciation that much of the damage is delayed [27]. This form of brain damage was first clearly defined as "diffuse degeneration of white matter" in a series of patients with post-traumatic dementia [32]; it is now widely recognised under a variety of synonyms including shearing injury [24, 33], diffuse damage of immediate impact type [3], diffuse white matter shearing injury [35], inner cerebral trauma [16] and, more recently, diffuse axonal injury (DAI) [4]. Unfortunately, classic axonal bulbs cannot be identified by conventional histological techniques until about 15 h after the injury [2]. Thus, a definite diagnosis of DAI could not, until recently, be made in patients who survive for only a short time after their injury. However, a diagnosis in cases with a shorter survival can now be made and has been greatly facilitated by the use of immunohistochemistry on either freshly frozen brain tissue [15, 34] or paraffin-embedded material [14]. It has been shown in a number of centres, including our own, that using an antibody to the [3-amyloid precursor protein ([3-APP) evidence of axonal damage [14] can be seen after a survival of as little as 3 h [30]. In this current study we have expanded on our initial observations and evaluated the frequency of axonal damage, using [3-APP immunocytochemistry, to determine if the phenomenon is more common than previously recognised using classic silver impregnation techniques. If this is the case, it would give further support to the belief that damage to nerve fibres is one of the most important causes of mortality and morbidity after head injury.
Materials and methods This study is based on further analysis of material obtained from 25 fatal head injuries autopsied by two of us (J.H.A. and D.I.G.) in 1990, in the Institute of Neurological Sciences, Glasgow. Briefly,
538
Fig. 1 Comparison between the Palmgren silver impregnation method (a, c and e) and ~-amyloid precursor protein (~-APP) immunostaining (b, d and f) in their ability to identify axonal damage in sections with an axonal rating score of 1 (a, b), 2 (c, d) and 3 (e, t'). Note that for all the scores it is easier to identify axonal damage and its extent in the ~-APP-stained sections, x 880 the brains from these patients were suspended in 10% formol saline for 3 - 4 weeks prior to dissection; the cerebral hemispheres were sliced in the coronal plane at 1-cm intervals, the cerebellum at right angles to the folia and the brain stem horizontally. Comprehensive histological studies were undertaken on multiple paraf-
fin-embedded blocks from the cerebral hemispheres, the cerebellum and the brain stem. Sections were stained with haematoxylin and eosin, Luxol fast blue/cresyl violet and by the Palmgren technique for axons. As previously described all macroscopic and histological abnormalities were drawn on a series of line diagrams, recorded on a proforma and the data stored on the University of Glasgow's mainframe computer [2]. Using these classic histological methods, diffuse axonal injury had been diagnosed in 8 of the 25 cases using the principal criterion of axonal bulb formation in the parasagittal white matter, corpus callosum, thalamus and upper brain stem [4]. For the purposes of the present study additional sections were cut from selected blocks (parasagittal white matter, corpus callo-
539 sum, upper brain stem and internal capsule) from the 25 head-injured patients already studied (age range 3-79 years, mean 34 + 4.7 years), 16 neuropathological controls (age range 12-81 years, mean 48 + 5.7 years) and 7 non-neurological controls (age range 17-84 years, mean 55 + 9.1 years). Sections were stained by the Palmgren technique for axons and adjacent sections immunosrained for [3-APP. For the immunostaining, endogenous peroxidase activity was blocked by incubation in 0.3% H202 in phosphatebuffered saline (PBS) for 30 min and then sections were pretreated with 80% formic acid for 8 rain before being incubated with the [3APP antibody (clone 22c 11, Boehringer) diluted 1:50 in PBS overnight at 4~ The antigen was detected using the Vectastain Elite system (Vector Labs, UK) and visualised using a 0.025% solution of diaminobenzidine in PBS. Sections were then dehydrated and mounted. The additional sections from each case were examined "blind" to the previous diagnosis. In the Palmgren-stained sections the evaluation was based on the presence of axonal bulbs as described previously (Fig. la, c, e). When assessing the immunostained sections various changes were apparent that ranged from the accumulation of ~-APP in slightly dilated but otherwise normal axons, to the accumulation of [3-APP in varicose axons, and axonal bulb formation. If none of these features were present within any of the tissue sections examined they were rated as zero. If there was any staining of axons, however slight, the case was given a rating score of 1. A rating score of 2 was given when there were scattered patches of axonal damage, while a rating score of 3 was reserved for cases where there was extensive damage throughout large areas of the white matter (Fig. lb, d, f). There was a high degree of correlation between the independent observers (S.M.G.and D.I.G.), and in those sections where there was some discrepancy (13%) the sections were re-examined and a consensus rating produced.
Table 1 Details of age, sex, survival and neuropathological findings using classical techniques in 25 head-injured patients (H). (Fract fracture, Con contusions, 1CH intracranial haematoma, DAI diffuse axonal injury, M macroscopic, m microscopic, ICP in-
Results D e t a i l s o f t h e a g e , g e n d e r , t y p e o f injury, s u r v i v a l a n d principal neuropathological findings using classic techn i q u e s in t h e 25 h e a d - i n j u r e d p a t i e n t s are g i v e n in T a b l e 1. S i m i l a r d e t a i l s f o r t h e c o n t r o l s are g i v e n in T a b l e 2. H i s t o l o g i c a l e v i d e n c e o f D A I w a s s o u g h t in t h e s e c tions recently stained by the P a l m g r e n method. U s i n g the c r i t e r i o n o f a x o n a l b u l b f o r m a t i o n it w a s c o n f i r m e d t h a t a x o n a l i n j u r y w a s p r e s e n t in 8 o f t h e 25 h e a d i n j u r y c a s e s ; a l t h o u g h s o m e b u l b s w e r e p r e s e n t in t h e r e m a i n i n g 17 cases, they could be accounted for by the other patholog i e s o f h e a d injury, i.e. i n f a r c t i o n , o r h a e m a t o m a , a n d t h e r e f o r e d i d n o t h a v e t h e d i s t r i b u t i o n t h a t is n e c e s s a r y to allow a diagnosis of DAI. Examination of the immunostained sections revealed e v i d e n c e o f a x o n a l d a m a g e in all 25 h e a d i n j u r y c a s e s ; h o w e v e r , in o n l y 23 c a s e s w a s it p o s s i b l e to i d e n t i f y b u l b s (Fig. 2.). T h e t w o c a s e s in w h i c h b u l b s c o u l d n o t b e i d e n t i f i e d w e r e c a s e s 10 a n d 11, b o t h o f w h i c h h a d s u r v i v e d f o r l e s s t h a n 1 2 h f o l l o w i n g injury. C o m p a r i s o n s b e t w e e n the i m m u n o s t a i n e d and silver slides c o n f i r m e d that the b u l b s f o u n d in t h e a d d i t i o n a l c a s e s c o u l d n o t b e i d e n t i f i e d in t h e P a l m g r e n - s t a i n e d s e c t i o n s a n d t h a t t h e i r d i s t r i b u t i o n could not be accounted for by the presence of other types
tracranial pressure, RTA road traffic accident, SDH subdural haematoma, E D H extradural haematoma, IC intracranial haematoma, Min minor, Soy severe, M o d moderate, NA not applicable)
Case
Age (years)
Sex
Type of injury
Survival time
Fract
Con
ICH
Ischaemic damage
Oedema DAI
Raised ICP
HI H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14 H15 H16 H17 H18 H 19 H20 H21 H22 H23 H24 H25
33 60 28 18 16 19 62 24 79 14 39 3 25 16 71 59 5 6 62 19 14 21 32 51 74
M F M M M M M M F M M F M M M F F M M M M M M M M
Fall RTA RTA RTA RTA RTA Fall RTA RTA RTA Fall RTA RTA Assault Fall Fall RTA RTA Fall RTA RTA RTA Fall RTA Fall
26 days 18 h 18 h 5 days 2 days 13 h 24 h 2 days 36 h 7h 2h 24 h 12 h 60 h < 24 h 5 days 9 days 24 h 11 days 24 h 4 days 2 days 5 days 24 h 23 h
+ + + + + + + + + + + . + + + + + + + + + -
Mild Mod Mod Mild Mod Mod Mod Mod Mod Mod Mild Mod
SDH SDH SDH IC,SDH SDH . . . . IC . EDH SDH SDH EDH,SDH . . SDH SDH,ICH SDH
Min Min Sev Mod Sev Sev Min Min Sev . . Min Min
+ + + -
2m lm 3M lm lm -
+ + + + + + +
3M 3M 3M -
+ + + + + + + +
-
+ + +
.
. Mod Mod Mod Mod Mod Mod Mod Mod Mod -
Mod Sev Sev Min Sev . Sev Sev NA
. .
. . + + + -
.
. + -
540 T a b l e 2 Details of age, sex, survival and principle pathological findings in neuropathological control patients (N) and normal controls (C) (fl-APP ~-amyloid precursor protein, ICP intracranial
pressure, IHD ischaemic heart disease, ADEM acute disseminated encephalomyelitis)
Case
Age (years)
Sex
Survival
Cause of death
Intracranial disease
~-APP
N1 N2 N3 N4 N5 N6 N7 N8 N9 N10 N11 N12 N13 N14 N 15 N16 C1 C2 C3 C4 C5 C6 C7
62 83 60 60 58 51 54 52 77 30 24 32 16 25 81 12 84 69 66 64 63 28 17
M F F M M M F M M M M M M M F M M M M M M F M
8 days 13 days 72 h 72 h Years 12 days Years 11 days Years 8 days 48 h 62 h 7 days 48 h 24 h 23 h 8 weeks 7 days 5 days 3 weeks 24 h 37 tl 24 h
Renal failure, Septicaemia Raised ICP Pneumonia Raised ICP Pneumonia,IHD Raised ICP Septicaemia Pneumonia Pulmonary embolism Raised ICP Purulent meningitis Raised ICP Pneumonia Suicide (hanging) Raised ICP Raised ICP Pneumonia, IHD Pneumonia Heart failure Liver failure Malnutrition Renal failure, Status epilepticus Septicaemia
Diffuse hypoxia HSV encephalitis Recent infarction Recent infarction Old infarction Recent infarction Multiple sclerosis Cerebral abscess Motor neuron disease ADEM Cerebral abscess Recent infarction Hypoglycaemic damage Diffuse hypoxia Recent infarction Diffuse hypoxia -
+ + + + + + + + + + + -
loo
....
* * *
. . . . . . . . . . . . . . .
1001 .....
-. .......
-
.~--~
80 80
+
6O
60 + o
40 40
20
20 0
Diagnostic method
"-
Fig. 2 Bar histogram illustrating the overall frequency of axonal bulb formation in the head-injury cases as determined by silver and immunohistochemical staining (*** P < 0.001) of traumatic brain injury. The immunostaining was significantly more sensitive than the Palmgren in detecting axo n a l b u l b s ( M c N e m a r ' s Z2; P < 0 . 0 0 1 ) . The frequency of axonal bulb formation in each of the f o u r a r e a s s t a i n e d b y t h e t w o m e t h o d s is s h o w n i n Fig. 3.
3
Fig. 3 Bar histogram illustrating the frequency of axonal damage in the four areas within the head-injury cases studied using silver and immunohistochemical staining. (*** P < 0.001; ** P < 0.01) Using the Palmgren method, bulb formation was seen equally commonly in the corpus callosum and in the upper pons, less commonly in the thalamus and internal capsule, and least commonly in the white matter of the
541 2.~
teaued at about 24 h, at which level it appeared to remain relatively constant for at least up to 48 h. The incidence of axonal damage was not restricted to the head injury cases. As is shown in Fig. 5, approximately 25% of the neuropathological controls also showed evidence of axonal injury in three or more areas. Evidence of axonal damage was found in only one area, the internal capsule, of one of the normal controls. This patient was the oldest in the study (84years) and the pathology can probably be attributed to the normal ageing process [18].
................
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E.1, 'o
g
Discussion 0
The main aim of this study was to determine the frequency of axonal damage following head injury using the immunocytochemical detection of ~-APP as reported prem r m r viously [14, 30]. The results suggest that the frequency of this phenomenon has been greatly underestimated in previous reports and that there is likely to be some degree of Survival time axonal damage in all cases of fatal head injury that cannot Fig. 4 Bar histogram showing the affect of survival time post be attributed to the pathologies of other traumatic brain head injury on the semiquantitative rating of axonal damage. Num- injury [2, 4]. Using bulb formation as the principal critebers above each column refer to the number of cases in each time rion of irreversible axonal injury, examination of the Palmspan gren-stained sections reconfirmed that evidence of DAI 100[ was seen only in 8 of the 25 head-injured cases (about 30%). In contrast, evidence of bulb formation was present in 23 of the 25 (92%) in the immunostained sections. The plot of axonal rating score against survival time eo provides additional evidence of what has been suspected for some time for humans, namely, that the amount of axonal damage, as shown by bulb formation, increases with I 60 . . . . . . . . . . . . . . . . survival time in the first 12-24h after an injury [2, 5, 25]. Thereafter, it appears to plateau before tailing off to the extent that by 60days post-injury axonal bulbs are less 40 . . . . . . . . . . . easy to identify at a time when the principal neuropathological feature is that of Wallerian degeneration [21]. A number of other axonally transported proteins have been o suggested as potential markers for axonal damage. For exN 2O . . . . . . ample, anti-ubiquitin [17] and anti-68-, 170- and 200-kDa neurofilament protein [22] immunostains have been tried with some success. However, in an extensive comparative study using antibodies to nine different antigens, includH N C ing ubiquitin and neurofilaments, [3-APP still produced Fig. 5 Bar histogram illustrating the percentage of cases with ev- the most sensitive and reliable staining of this form of idence of axonal injury in three or more areas as determined by ~3- damage [31]. APP immunostaining. (H head injury, N neuropathological conThe concept of the shearing of axons at the time of introl, C normal control) jury was postulated over 20years ago [24, 32, 33]. Since then the concept has changed, whereby axons are not torn parasagittal cortex. A similar pattern was seen in the by shear and tensile forces at the moment of injury (exsections stained with ~3-APR The two different stain- cept under extreme circumstances), but that there is focal ing techniques paralleled each other, although it was eas- axonal damage resulting in a focal impairment of axonal ier to identify bulbs using the immunohistochemical transport leading to axonal swellings. This concept is supmethod. ported by a number of laboratory studies investigating the The average axonal rating score plotted against sur- different severity of traumatic brain injury [8, 20, 26, 28] vival time is given in Fig. 4. From this it can be seen that or axonal shear in the optic nerve after stretch injury [13, the score is lower in cases surviving for 12h or less (mean 20]. From these different studies it is now quite clear that score = 1) than cases surviving for more than 12h (mean there is a time course for the development of axonal damscore = 2.1 + 0.17). The amount of axonal damage pla- age up to and including bulb formation.
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542 A s r e p o r t e d previously, there is an i n c r e a s e d expression o f ~ - A P P t h r o u g h o u t g r e y matter in h e a d - i n j u r e d patients but p a r t i c u l a r l y in p o p u l a t i o n s o f nerve cells c l o s e l y a s s o c i a t e d with a x o n a l d a m a g e [14]. H o w e v e r , ~ - A P P acc u m u l a t i o n is not unique to h e a d - i n j u r e d patients and was seen in areas o f focal d a m a g e in the n e u r o p a t h o l o g i c a l controls f r o m this study and b y others in a s s o c i a t i o n with c e r e b r a l infarction [23]. A s was a m p l y d e m o n s t r a t e d b y Sherriff et al. [30] i m m u n o s t a i n i n g for ~3-APP is not, therefore, a true d i a g n o s t i c m a r k e r for h e a d injury but rather it is an indicator o f local a n a t o m i c a l or m o r e general m e t a b o l i c d a m a g e within the brain. This acute role for [3-APP in a general stress r e s p o n s e is s u p p o r t e d b y data f r o m a n i m a l studies [1, 19] and our o w n observations in h e a d - i n j u r y patients [14, 29]. F r o m this p r e l i m i n a r y study it is c o n c l u d e d that s o m e d e g r e e o f axonal d a m a g e is l i k e l y to be present in all fatal cases o f h e a d injury. It is w e l l k n o w n in clinical neur o p a t h o l o g y that a survival o f at least 15 h f o l l o w i n g head injury is r e q u i r e d for bulb f o r m a t i o n to b e identified with certainty using classic silver i m p r e g n a t i o n techniques. E v e n then, b e c a u s e o f the v i c a r i o u s nature o f such techniques the r e c o g n i t i o n o f b u l b f o r m a t i o n m a y be difficult due to v a r i a b l e staining and staining o f glial nuclei in s o m e cases. Difficulties in interpretation are c o m p o u n d e d b y the finding that varicosities m a y be o f an artefactual nature [7], b e i n g a p r o d u c t o f h a n d l i n g u n f i x e d postm o r t e m tissue. E x a m i n a t i o n o f the i m m u n o s t a i n e d sections in the present study has s h o w n that e v i d e n c e o f a x o n a l d a m a g e is m u c h m o r e w i d e s p r e a d than was thought to be the case. N o t o n l y is this seen in the f o r m o f a c c u m u l a t i o n o f [3A P P in r e l a t i v e l y n o r m a l - l o o k i n g axons but also its accum u l a t i o n in v a r i c o s e axons. T h e s e findings m a y s i m p l y represent c h a n g e s in a x o p l a s m i c transport o f a t e m p o r a r y nature and therefore are occurring in axons w h i c h at least have the potential for r e c o v e r y [9-12]. T h e t i m e course o f such r e c o v e r y is unclear, but it is interesting to note that it was r e c e n t l y r e p o r t e d that ~ - A P P a c c u m u l a t i o n can be seen as long as 99 d a y s after a m i l d h e a d injury [6]. O f particular i m p o r t a n c e f r o m the p r e s e n t study, however, is the finding that in a d d i t i o n to these changes, the freq u e n c y o f b u l b f o r m a t i o n is m u c h m o r e c o m m o n than has b e e n identified b y the classic staining techniques. Indeed, b u l b f o r m a t i o n is f o u n d in 92% o f the patients studied in this series. This appears to p r o v i d e i n c o n t r o v e r t i b l e evidence that s o m e d e g r e e o f axonal injury with b u l b f o r m a tion is present in a great m a j o r i t y o f fatal h e a d injuries. Acknowledgement This work was supported in part by the Medical Research Council and the Alzheimer's Disease Society.
References 1. Abe K, Tanzi RE, Kogure K (1991) Selective induction of kunitz type protease inhibitor domain containing mRNA after persistent focal ischaemia in rat cerebral cortex. Neurosci Lett 125:172-174
2.Adams JH (1992) Head injury. In: Adams JH, Duchen LW (eds) Greenfield's neuropathology. Arnold, London, pp 106152 3.Adams JH, Mitchell DE, Graham DI, Doyle D (1977) Diffuse brain damage of immediate impact type. Brain 100:489-502 4.Adams JH, Doyle D, Ford I, Gennarelli TA, Graham DI, McLellan DR (1989) Diffuse axonal injury and head injury: definition, diagnosis and grading. Histopathology 15:49-59 5.Blumbergs PC, Jones NR, North JB (1989) Diffuse axonal injury and head trauma. J Neurol Neurosurg Psychiatry 52: 838-841 6. Blumbergs PC, Scott G, Manavis J, Wainwright H, Simpson DA, McLean AJ (1994) Staining of amyloid precursor protein to study axonal damage in mild head injury. Lancet 344: 1055-1056 7. Crooks DA (1991) A method to quantitate axonal injury. Neuropathol Appl Neurobiol 17:421-424 8. Erb DE, Povlishock JT (1988) Axonal damage in severe traumatic brain injury: an experimental study in the cat. Acta Neuropathol 76:347-358 9. Gennarelli TA (1983) Head injury in man and experimental animals: clinical aspects. Acta Neurochir [Suppl] (Wien), pp 113 10. Gennarelli TA (1993) Cerebral concussion and diffuse brain injuries. In: Cooper PR (ed) Head injury, 3rd edn. Williams & Wilkins, Baltimore, pp 137-158 11. Gennarelli TA, Spielman GM, Langfitt TW, Gildenberg PL, Harrington T, Jane JA, Marshall LF, Miller JD, Pitts LH (1982) Influence of the type of intracranial lesion on outcome from severe head injury. J. Neurosurg 56:26-36 12.Gennarelli TA, Adams JH, Graham DI (1986) Diffuse axonal injury: a new conceptual approach to an old problem. In: Baethmans A, Go KG, Unterberg A (eds) Mechanisms of secondary brain damage. Plenum, New York, pp 15-28 13. Gennarelli TA, Thibault LE, Tipperman R, Tomel G, Sergot R, Brown MD, Maxwell WL, Graham DI, Adams JH, Irvine A, Gennarelli LM, Duhaime AC, Broock R, Greenberg J (1989) Axonal injury in the optic nerve: a model simulating diffuse axonal injury in the brain. J Neurosurg 71:244-253 14.Gentleman SM, Nash MJ, Sweeting CJ, Graham DI, Roberts GW (1993) [3-Amyloid precursor protein (~3-APP) as a marker of axonal injury after head injury. Neurosci Lett 160:139-144 15.Grady MS, McLaughlin MR, Christman CW, Valadka AB, Fligner CL, Povlishock JT (1993) The use of antibodies targeted against the neurofilament subunits for the detection of diffuse axonal injury in humans. J Neuropathol Exp Neurol 52: 143-152 16.Grcevic N (1982) Topography and pathogenic mechanisms of lesions in "inner cerebral trauma". Rad Jugosl Akad Znan Umjet 402:265-331 17.Gultekin SH, Smith TW (1994) Diffuse axonal injury in craniocerebral trauma. A comparative histologic and immunohistochemical study. Arch Pathol Lab Med 118:168-171 18.Jellinger K (1973) Neuroaxonal dystrophy: its natural history and related disorders. Prog Neuropathol 2:129-180 19. Kawarabayashi T, Shoji M, Harigaya Y, Yamaguchi H, Hirai S (1991) Expression of APP in the early stages of brain damage. Brain Res 563:334-338 20. Maxwell WL, Irvine A, Graham DI, Adams JH, Gennarelli TA, Tipperman R, Sturatis M (1991) Focal axonal injury: the early axonal response to stretch. J Neurocytol 20:157-164 21.McLellan DR, Adams JH, Graham DI, Kerr AE, Teasdale GM (1986) The structural basis of the vegetative state and prolonged coma after non-missile head injury. In: Papo I, Cohadon F, Massarotti M (eds) Le coma traumatique. Liviana, Padova, pp 165-185 22.Ng HK, Mahaliyana RD, Pooh WS (1994) The pathological spectrum of diffuse axonal injury in blunt head trauma: assessment with axon and myelin stains. Clin Neurol Neurosurg 96: 24-31
543 23. Ohgami T, Kitamoto T, Tateishi J (1992) Alzheimer's amyloid precursor protein accumulates within axonal swellings in human brain lesions. Neurosci Lett 136:75-78 24.Peerless SJ, Rewcastle NB (1967) Shear injuries of the brain. Can Med Assoc J 96:577-582 25.Pilz P (1983) Axonal injury in head injury. Acta Neurochir [Suppl] (Wien) 32:119-123 26.Povlishock JT (1986) Traumatically induced axonal change without concomitant change in focally related neuronal somata and dendrites. Acta Neuropathol (Bed) 70:53-79 27.Povlishock JT (1992) Traumatically induced axonal injury: pathogenesis and pathobiological implications. Brain Pathol 2: 1-12 28. Povlishock JT, Becker DP, Cheng CLY, Vaughan CW (1983) Axonal change in minor head injuries. J Neuropathol Exp Neurol 42:225-242 29. Roberts GW, Gentleman SM, Lynch A, Murray L, Landon M, Graham DI (1994) 13-Amyloid protein deposition in the brain after severe head injury: implications for the pathogenesis of Alzheimer's disease. J Neurol Neurosurg Psychiatry 57: 419425
30. Sherriff FE, Bridges LR, Sivaloganathan S (1994) Early detection of axonal injury after human head trauma using immunocytochemistry for ~-amyloid precursor protein. Acta Neuropathol 87:55-62 31. Sherriff FE, Bridges LR, Gentleman SM, Sivaloganathan S, Wilson S (1994) Markers of axonal injury in post mortem human brain. Acta Neuropathol 88:433-439 32. Strich SJ (1956) Diffuse degeneration of the cerebral white matter in severe dementia following head injury. J Neurol Neurosurg Psychiatry 19:163-185 33.Strich SJ (1961) Shearing of nerve fibres as a cause of brain damage due to head injury. Lancet II: 443-448 34. Yaghmai A, Povlishock J (1992) Traumatically induced reactive changes as visualised through the use of monoclonal antibodies targeted to neurofilament subunits. J Neuropathol Exp Neurol 51:158-176 35. Zimmerman RA, Larissa T, Bilaniuk LT, Gennarelli TA (1978) Computerised tomography of shearing injuries of the cerebral white matter. Radiology 127:393-396
