J Neurol (1990) 237:356-361
Joumal of
Neurology
© Springer-Verlag 1990
Traumatic and spontaneous extracranial internal carotid artery dissections* B. Mokri Department of Neurology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA Received November 28, 1989 / Received in revised form May 15, 1990 / Accepted June 9, 1990
Summary. S e v e n t y p a t i e n t s with s p o n t a n e o u s a n d 21 with t r a u m a t i c e x t r a c r a n i a l i n t e r n a l c a r o t i d a r t e r y dissections w e r e s t u d i e d clinically a n d a n g i o g r a p h i c a l l y with m e a n follow-ups of 64 ( s p o n t a n e o u s group) and 40 months ( t r ä u m a t i c g r o u p ) . Sixty p e r c e n t of the p a t i e n t s in the s p o n t a n e o u s g r o u p a n d 71% in t h e t r a u m a t i c g r o u p also h a d f o l l o w - u p a n g i o g r a m s . In t r a u m a t i c dissections ane u r y s m s w e r e c o m m o n , significantly f e w e r a n e u r y s m s resolved or became smaller and fewer stenoses resolved o r i m p r o v e d , w h e r e a s m o r e s t e n o s e s p r o g r e s s e d to occlusion. T r a u m a t i c d i s s e c t i o n s w e r e m o r e likely to leave t h e p a t i e n t s with n e u r o l o g i c a l deficits. A significantly h i g h e r p e r c e n t ä g e o f t h e p a t i e n t s with s p o n t a n e o u s diss e c t i o n s w e r e a s y m p t o m a t i c at f o l l o w - u p c o m p a r e d with the traumatic group. Although both spontaneous and t r a u m a t i c d i s s e c t i o n s of e x t r a c r a n i a l i n t e r n a l c a r o t i d art e r i e s m o s t l y c a r r y a g o o d p r o g n o s i s , the o u t c o m e m a y b e s o m e w h a t less f a v o r a b l e for t h e t r a u m a t i c g r o u p . Key words: C a r o t i d d i s s e c t i o n - S p o n t a n e o u s c a r o t i d d i s s e c t i o n - T r a u m a t i c c a r o t i d d i s s e c t i o n - C a r o t i d artery trauma
lntroduction I n t h e p a s t two d e c a d e s t h e r e has b e e n an i n c r e a s i n g f a m i l i a r i t y with the clinical a n d the a n g i o g r a p h i c f e a t u r e s o f s p o n t a n e o u s a n d t r a u m a t i c dissections o f the e x t r a c r a nial i n t e r n a l c a r o t i d a r t e r i e s ( I C A s ) [3, 8 - 1 0 , 12-19, 21, 22, 24]. T h e s e d i s s e c t i o n s are u n c o m m o n b u t a r e n o t r a r e . T h e y o c c u r w h e n the circulating b l o o d p e n e t r a t e s the a r t e r i a l wall, u s u a l l y splitting the m e d i a a n d c r e a t i n g a false l u m e n t h a t dissects t h e a r t e r i a l wall for v a r y i n g dis'~ Presented in part at the meeting of the European Neurological Society, Nice, France, 19-22 June 1988 Offprint requests to." B. Mokri, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
t a n c e s [2]. If the i n t r a m u r a l h e m a t o m a e x p a n d s t o w a r d the a d v e n t i t i a , an a n e u r y s m a l d i l a t a t i o n m a y f o r m (a ù dissecting a n e u r y s m " ) . S o m e dissections o c c u r a f t e r a definite h e a d o r n e c k injury ( t r a u m a t i c dissections), a n d o t h e r s occur w i t h o u t history of definite t r a u m a ( s p o n t a n e o u s dissections), a l t h o u g h at t i m e s t h e r e m a y b e history o f m i n i m a l o r trivial t r a u m a . Practically, t h e r e s e e m s to be a d i f f e r e n c e b e t w e e n the e x t r a c r a n i a l I C A dissections c a u s e d b y definite s e v e r e h e a d a n d n e c k t r a u m a and those o c c u r r i n g s p o n t a n e o u s l y , with o r w i t h o u t a history of m i n i m a l o r trivial t r a u m a [13]. This s t u d y was c o n d u c t e d to c o m p a r e t h e clinical a n d a n g i o g r a p h i c f e a t u r e s as well as the o u t c o m e of t h e s e two g r o u p s .
Materials and methods The records of patients with a diagnosis of spontaneous or traumatic subintimal dissection, dissecting aneurysm, or dissection of an ICA, seen at Mayo Clinic prior to 1985, were reviewed. Twenty-one patients with traumatic extracranial ICA dissections (15 men, 6 women) and 70 patients with spontaneous ICA dissections (29 men, 41 women) were identified. Age and duration of clinical and angiographic follow-up of these patients are summarized in Table 1. The follow-up evaluation included one or more neurologic examinations in 79 patients (including-all of the patients with traumatic ICA dissections), telephone calls in 75, and follow-up letters in 15. Information regarding persistence or resolution of symptoms and signs, resumption of normal activities, and return to work were recorded. On follow-up arteriography, 22 ICAs of the traumatic group and 52 ICAs of the spontaneous group had been re-studied. If a patient had undergone resection of the extracranial ICA dissecting aneurysm, the specimens were subjected to pathology studies. On initial evaluation, all of the patients had undergone conventional arteriography. Of the 15 patients with traumatic dissections who had follow-up angiograms, this consisted of intravenous (i.v.) digital subtraction angiography (DSA) in 2 patients and transfemoral conventional angiography in 13 patients (2 of whom had also undergone DSA). The interval from the initial to the last angiogram was 2 weeks to 3.5 years. Initial angiograms were done within hours of the accident in 11 cases, within days in 4 cases, within months in 2 cases, and within years in 4 cases (in these delayed cases neurologic manifestations had developed long after the
357 Table 1. Patients with traumatic or spontaneous extracranial inter-
Table 2. Frequency of symptoms and signs in 70 patients with
nal carotid artery (ICA) dissections
spontaneous and 21 patients with traumatic dissections of extracranial ICA
Data
Patient group Spontaneous
Traumatic
No. of patients
70 (29 M, 41 F)
21 (15 M, 6 F)
Patient age (years) Range Mean
18-76 41
19-55 32
Duration of follow-up Range Mean
22 months-9.5 years 64 months
4 days-7.5 years 40 months a
No. of patients with follow-up angiography (%)
42 (60)
15 (71)
a Excluding two patients who died 4 and 6 days after the accident as the result of massive cerebral infarct and edema
accident as the result of embo|ization from thrombi within the residual dissecting aneurysms). Of the 42 patients with spontaneous dissections who underwent follow-up angiography, this was a conventional arteriogram in 29 and i.v. DSA in 13. These had been carried out within 1 month to 6.5 years after the initial angiogram. The initial angiogram had been done within a few days after the onset of the symptoms in 62 cases and within 1 month in all but 3 cases. The X2 test and Fisher's exact test were used to evaluate the data.
Results
CIinical findings Spontaneous group. H e a d a c h e , the m o s t c o m m o n sympt o m (Table 2), was often unilateral (73%), and it was usually focal and located in the orbital, periorbital, and frontal regions. T h e o t h e r c o m m o n locations were mastoid region and d e e p in the ear, t e m p o r a l region, angle of the mandible, face, and finally occipital region. Focal cerebral ischemic s y m p t o m s [transient ischemic attack ( T I A ) and stroke] usually were d e l a y e d and followed a h e a d a c h e by a period ranging f r o m a few minutes to 2 weeks. A l t h o u g h the clinical picture varied and s o m e of the patients p r e s e n t e d with only focal ischemic events ( T I A , stroke, amaurosis fugax), or lower cranial nerve palsies, or h e a d a c h e and bruits, m a n y p r e s e n t e d with one o f the following distinct syndromes: hemicrania and o c u l o s y m p a t h e t i c palsy (OSP) (12 patients), hemicrania and delayed focal cerebral ischemic events (20 patients), and c o m b i n a t i o n of hemicrania, OSP, and focal cerebral ischemic events (15 patients). F o r t y p e r c e n t o f the patients were hypertensive and 16% had angiographic evid e n c e of fibromuscular dysplasia in carotid, vertebral, or renal arteries.
Traumatic group. Focal cerebräl ischemic symptoms were the m o s t c o m m o n of the clinical manifestations and often o c c u r r e d at s o m e time after the accident, sometimes m o n t h s or years (see the f o o t n o t e to Table 2). These de-
Symptom or sign
Headache Focal cerebral ischemic symptoms TIAs Stroke TIAS and stroke Oeulosympathetic paresis Bruits (subjective, objective, or both) Neck pain Light-headedness Syncope Amaurosis fugax Scalp tenderness Neck swetling Dysgeusia Lower cranial nerve palsies Asymptomatic° Sensation of pulsation in neck
Patient group Spontaneous
Traumatie
No.
%
No.
%
59 43
84 61
8 15 a
38 71 2 11 2
24 13 6 37
53
7
33
32 16 15 8 8 5 3 2 2 1 1
46 23 21
8 1b
38
2 1
1
Offen delayed after the accident: within 30min-12h, 6; within 4-20 days, 3; in 2 months, 1; after 6-10 years, 5 b Excluding any neck pain in connection with the original trauma c Symptoms related to a concomitant vertebral artery dissection TIA, Transient ischemic attack
layed ischemic s y m p t o m s were caused by e m b o l i z a t i o n f r o m t h r o m b i within the residual p o s t - t r a u m a t i c dissecting aneurysms as d e m o n s t r a t e d angiographically or by pathologic e x a m i n a t i o n of the excised dissecting aneurysms (Fig. 1). All patients had suffered m o d e r a t e to m a r k e d blunt t r a u m a , with m o t o r vehicle accident as the leading cause (62%). All but 3 patients had suffered other injury in addition to the I C A injury.
Angiographic findings These abnormalities (Table 3) have b e e n previously described by us and by others [5, 8, 10-14, 16, 19, 20]. T h e luminal stenosis was frequently irregular and often elongated and tapered. A n e u r y s m s were saccular or were elongated, ovoid, or finger-like. T h e u p p e r third of the extracranial I C A and subcranial region was the m o s t c o m m o n site, but the aneurysms also were seen frequently in the mid-third of the I C A and with a lesser f r e q u e n c y in the lower third of the I C A . Occlusions were often 2 3 cm distal to the carotid bifurcation and were usually tap e r e d to a point with a flame-like configuration. I C A dissection was bilateral in 20 patients (29%) in the spont a n e o u s g r o u p and in 8 patients (38%) in the traumatic group. C o n c o m i t a n t vertebral artery dissection was n o t e d in 3 patients in the s p o n t a n e o u s g r o u p and in 2 patients in the traumatic group.
358
Fig. 1. a Right carotid arteriogram demonstrates an elongated dissecting aneurysm (post-traumatic in this case). Contrast-filled true lumen is irregular due to filling of false lumen by thrombus. Also noted is a long intimal flap (arrows). b Cross section of a segment of the lesion demonstrates section through the internal carotid artery (ICA) and the related dissecting aneurysm. Note that the aneurysm is formed within the media. The external elastic lamina (thin arrows) surrounds both the true lumen of the ICA (asterisk) and the thrombus-filled false lumen of the aneurysm (FL). The false lumen has compressed the true lumen
(thick arrows)
Table 3. Angiographic findings in 90 ICAs (of 70 patients) with spontaneous dissection and 29 ICAs (of 21 patients) with traumatic dissection
t h o u g h o n l y 23% of the p a t i e n t s w e r e c o m p l e t e l y a s y m p tomatic.
Angiographic findings
Angiographic follow-up. In the s p o n t a n e o u s g r o u p , 52
Luminal stenosis Aneurysm Intimal flaps Slow ICA-MCA flow Occlusion Distal branch occlusions (emboli)
Patient group Spontaneous
Traumatic
No.
To
No.
%
69 35 25 22 15 11
77 39 28 24 17 12
13 17 7 3 8 3
45 59 24 10 28 10
MCA, Middle cerebral artery
d i s s e c t e d 1CAs (of 42 p ä t i e n t s ) w e r e r e s t u d i e d . O f 20 ane u r y s m s n o t e d in the initial a n g i o g r a m s , 6 r e m a i n e d unc h a n g e d , and 12 e i t h e r d e c r e a s e d in size o r r e s o l v e d (obl i t e r a t e d ) . O f the 40 s t e n o s e s , m o r e t h a n 87% e i t h e r c o m p l e t e l y o r p a r t i a l l y r e s o l v e d . O f 7 occlusions, o n l y 1 r e c a n a l i z e d , and the rest r e m a i n e d u n c h a n g e d . T w e n t y - t w o d i s s e c t e d I C A s (of 15 p a t i e n t s ) in the traumatic group were restudied angiographically. Only 3 of the 14 a n e u r y s m s n o t e d in the initial a n g i o g r a m dec r e a s e d in size or r e s o l v e d . A l s o , o n l y 6 o f the 11 s t e n o ses c o m p l e t e l y o r p a r t i a l l y r e s o l v e d , a n d 3 s t e n o s e s p r o g r e s s e d to occlusion. N o n e o f the 5 occlusions n o t e d initially r e c a n a l i z e d .
Follow-up
Treatment
Clinicalfollow-up. O f t h e s p o n t a n e o u s g r o u p , 76% w e r e a s y m p t o m a t i c , 1 d i e d o f u n r e l a t e d c a u s e ( c o l o n carcinom a ) , a n d o n l y 4 p a t i e n t s h a d m a r k e d o r m o d e r a t e deficits ( T a b l e 4). M i l d deficits o r r e s i d u a l r e c u r r e n t h e a d a c h e s w e r e p r e s e n t in 12% o f the p a t i e n t s . T h e h e a d aches w e r e s e v e r e in 2 p a t i e n t s . O v e r a l l , 59 p a t i e n t s ( 8 5 % ) m a d e c o m p l e t e o r e x c e l l e n t r e c o v e r i e s . O f the t r a u m a t i c g r o u p , 2 d i e d of m a s s i v e c e r e b r a l infarct and e d e m a a n d 4 h a d m o d e r a t e o r m a r k e d deficits. O v e r a l l , 71% h a d m a d e an e x c e l l e n t o r a c o m p l e t e r e c o v e r y , al-
D i f f e r e n t t r e a t m e n t m o d a l i t i e s h a d b e e n u s e d ( T a b l e 5) d e p e n d i n g u p o n the clinical m a n i f e s t a t i o n s , j u d g m e n t of the clinicians i n v o l v e d in the case, a n d the a m o u n t o f inf o r m a t i o n a v a i l a b l e at the t i m e r e g a r d i n g the n a t u r a l history of the disease. In the s p o n t a n e o u s g r o u p , a b o u t o n e - t h i r d r e c e i v e d no specific t r e a t m e n t . S e v e n p a t i e n t s h a d r e c e i v e d c o r t i c o s t e r o i d s p r i o r to t h e i r r e f e r r a l to us with the i m p r e s s i o n of " a r t e r i t i s " on the basis o f angiog r a p h i c findings of an i r r e g u l a r e l o n g a t e d s e g m e n t o f I C A . This t r e a t m e n t was t e r m i n a t e d in all 7. A c o n s i d e r -
359 Table 4. Follow-up in spontaneous and traumatic dissections of
ICA
Treatment modality
Patient group
Clinical follow-up Died Marked or moderate deflcits Mild deficitsa Mild or no deficits but residual headaches Asymptomatic Died of unrelated cause Angiographic follow-up
Spontaneous
Traumatic
No.
%
No.
%
0 4 7
0 6 10
2 4 6
10 19 29
5 53 1
7 76
4 5 0
19 24
(52 ICAs of 42 patients)
Aneurysm Eliminated by resection Unchanged Decreasedinsize Resolved Not visualizedb
20
Stenosis Resolution, complete Resolution, partial Progression ~ Progression to occlusion Elimination by resection Unchanged Occlusion Recanalization No change
40
14 4 5 2 1 2
29 36 14 7
4 2 1 3 1 0
36 18 9 27 9
11 23 58 12 30 2 5 2 5 0 1 5 1 6
Supportive only Anticoagulant therapy Antiplatelet therapy Surgery
No. of patients a Spontaneous
Traumatic
22 18 40
3 6 9 10~
9b
a Some patients received more than one of these modalities b Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass in 8 patients, ICA exploration in 1 patient « Resection and interposition graft in 5 patients, STA-MCA bypass ICA ligation in I patient, removal of MCA embolus and STAMCA bypass in 1 patient
(22 ICAs of 15 patients)
0 6 30 8 40 4 20 2
7
Table 5. Treatment modalities implemented in 70 patients with spontaneous and 21 patients with traumatic ICA dissections
0 5
a Not interfering with work or daily activities (i.e., slight paresis, mild sensory deficits, reflex asymmetries, slight dyscalculia, oeulosympathetic palsy, bruits) b As the result of ligation of parent vessel in one case and as the result of progression of stenosis to occlusion in the other cases c With additional appearance of a small aneurysm in the midsegment of extracranial ICA
ably larger proportion of the traumatic group had undergone operation, mostly consisting of resection of the residual aneurysm (considered to be the source of embolization) (Fig. 1). We now rarely operate on a patient with spontaneous I C A dissection. The indications and the rationale for surgical treatment in the traumatic group have been discussed in a previous publication [19].
Discussion
The clinical and angiographic features, as well as the outcome of spontaneous and traumatic I C A dissections, have been discussed in many papers [4, 10, 11, 13, 14, 18, 19, 24]. Traumatic dissections of the I C A resulting from blunt injuries are less common. Their clinical manifestations vary. In severe traumas, especially when the
patient is initially comatose or has suffered multiple organ injuries, traumatic I C A dissections may go undiagnosed. Patients who survive these severe traumas may have no neurologic deficits related to their undiagnosed I C A dissection or may have deficits that are often interpreted as related to "head injury" and thus angiography is not carried out. Some of these patients have residual traumatic dissecting aneurysms that may become symptomatic even years later by causing focal cerebral ischemic symptoms as the result of embolization from a thrombus within the aneurysm [19]. Spontaneous I C A dissections also may sometimes go undiagnosed because at times they may cause only mild or trivial symptoms or be entirely asymptomatic (for example, diagnosed incidentally during work-up of a patient with spontäneous vertebral artery dissection or the opposite I C A dissection). Symptoms delayed for years in spontaneous dissections, however, have been most unusual in our experience. A m o n g more than 100 cases of spontaneous I C A dissections seen by us, only 1 patient presented with symptoms due to embolization from a thrombus within a dissecting aneurysm, which was thought to have existed for years as the result of an undiagnosed spontaneous dissection (B. Mokri, unpublished data). Clinically, in the traumatic group the most c o m m o n picture was appearance of focal cerebral ischemic manifestations (TIAs or strokes) delayed from the accident for periods ranging from hours to years (Table 2). The most c o m m o n clinical pictures in the spontaneous group were hemicrania and Horner's syndrome (17%), or hemicrania and delayed focal cerebral ischemic manifestations (29%), or a combination of both (21%). Major clinical and angiographic features of the traumatic and spontaneous groups are compared in Table 6 and listed in decreasing order of statistical significance. However, it should be pointed out that, from the statistical point of view, the numbers, particularly of the traumatic group, are not large. It is possible that larger numbers could establish more or other significant differences. Cerebral ischemic events appeared to be somewhat more c o m m o n in the traumatic group, but not significantly so. Headaches (offen unilateral) were significantly more c o m m o n
360 Table 6. Major clinical and angiographic features and follow-up of
traumatic and spontaneous extracranial ICA dissections Feature
Patients or ICAs, % (no. involved/total no.) Spontaneous Traumatic
Death Headaches Asymptomatic at follow-up Stenosis Decrease in size or resolution of aneurysm at follow-up Partial or complete resolution of stenosis at follow-up Progression of stenosis to occlusion Aneurysm Marked or moderate deficit at follow-up Oculosympatheticpalsy Occlusion Residual recurrent hemicrania at follow-up Concomitant dissection of vertebralartery Focal cerebral ischemic events Bilaterality Bruits
P
0 (0/70) 84 (59/70) 76 (53/70) 77 (69/90)
10 (2/21) 38 (8/21) 24 (5/21) 45 (13/29)
Joumal of
Neurology
© Springer-Verlag 1990
Traumatic and spontaneous extracranial internal carotid artery dissections* B. Mokri Department of Neurology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA Received November 28, 1989 / Received in revised form May 15, 1990 / Accepted June 9, 1990
Summary. S e v e n t y p a t i e n t s with s p o n t a n e o u s a n d 21 with t r a u m a t i c e x t r a c r a n i a l i n t e r n a l c a r o t i d a r t e r y dissections w e r e s t u d i e d clinically a n d a n g i o g r a p h i c a l l y with m e a n follow-ups of 64 ( s p o n t a n e o u s group) and 40 months ( t r ä u m a t i c g r o u p ) . Sixty p e r c e n t of the p a t i e n t s in the s p o n t a n e o u s g r o u p a n d 71% in t h e t r a u m a t i c g r o u p also h a d f o l l o w - u p a n g i o g r a m s . In t r a u m a t i c dissections ane u r y s m s w e r e c o m m o n , significantly f e w e r a n e u r y s m s resolved or became smaller and fewer stenoses resolved o r i m p r o v e d , w h e r e a s m o r e s t e n o s e s p r o g r e s s e d to occlusion. T r a u m a t i c d i s s e c t i o n s w e r e m o r e likely to leave t h e p a t i e n t s with n e u r o l o g i c a l deficits. A significantly h i g h e r p e r c e n t ä g e o f t h e p a t i e n t s with s p o n t a n e o u s diss e c t i o n s w e r e a s y m p t o m a t i c at f o l l o w - u p c o m p a r e d with the traumatic group. Although both spontaneous and t r a u m a t i c d i s s e c t i o n s of e x t r a c r a n i a l i n t e r n a l c a r o t i d art e r i e s m o s t l y c a r r y a g o o d p r o g n o s i s , the o u t c o m e m a y b e s o m e w h a t less f a v o r a b l e for t h e t r a u m a t i c g r o u p . Key words: C a r o t i d d i s s e c t i o n - S p o n t a n e o u s c a r o t i d d i s s e c t i o n - T r a u m a t i c c a r o t i d d i s s e c t i o n - C a r o t i d artery trauma
lntroduction I n t h e p a s t two d e c a d e s t h e r e has b e e n an i n c r e a s i n g f a m i l i a r i t y with the clinical a n d the a n g i o g r a p h i c f e a t u r e s o f s p o n t a n e o u s a n d t r a u m a t i c dissections o f the e x t r a c r a nial i n t e r n a l c a r o t i d a r t e r i e s ( I C A s ) [3, 8 - 1 0 , 12-19, 21, 22, 24]. T h e s e d i s s e c t i o n s are u n c o m m o n b u t a r e n o t r a r e . T h e y o c c u r w h e n the circulating b l o o d p e n e t r a t e s the a r t e r i a l wall, u s u a l l y splitting the m e d i a a n d c r e a t i n g a false l u m e n t h a t dissects t h e a r t e r i a l wall for v a r y i n g dis'~ Presented in part at the meeting of the European Neurological Society, Nice, France, 19-22 June 1988 Offprint requests to." B. Mokri, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
t a n c e s [2]. If the i n t r a m u r a l h e m a t o m a e x p a n d s t o w a r d the a d v e n t i t i a , an a n e u r y s m a l d i l a t a t i o n m a y f o r m (a ù dissecting a n e u r y s m " ) . S o m e dissections o c c u r a f t e r a definite h e a d o r n e c k injury ( t r a u m a t i c dissections), a n d o t h e r s occur w i t h o u t history of definite t r a u m a ( s p o n t a n e o u s dissections), a l t h o u g h at t i m e s t h e r e m a y b e history o f m i n i m a l o r trivial t r a u m a . Practically, t h e r e s e e m s to be a d i f f e r e n c e b e t w e e n the e x t r a c r a n i a l I C A dissections c a u s e d b y definite s e v e r e h e a d a n d n e c k t r a u m a and those o c c u r r i n g s p o n t a n e o u s l y , with o r w i t h o u t a history of m i n i m a l o r trivial t r a u m a [13]. This s t u d y was c o n d u c t e d to c o m p a r e t h e clinical a n d a n g i o g r a p h i c f e a t u r e s as well as the o u t c o m e of t h e s e two g r o u p s .
Materials and methods The records of patients with a diagnosis of spontaneous or traumatic subintimal dissection, dissecting aneurysm, or dissection of an ICA, seen at Mayo Clinic prior to 1985, were reviewed. Twenty-one patients with traumatic extracranial ICA dissections (15 men, 6 women) and 70 patients with spontaneous ICA dissections (29 men, 41 women) were identified. Age and duration of clinical and angiographic follow-up of these patients are summarized in Table 1. The follow-up evaluation included one or more neurologic examinations in 79 patients (including-all of the patients with traumatic ICA dissections), telephone calls in 75, and follow-up letters in 15. Information regarding persistence or resolution of symptoms and signs, resumption of normal activities, and return to work were recorded. On follow-up arteriography, 22 ICAs of the traumatic group and 52 ICAs of the spontaneous group had been re-studied. If a patient had undergone resection of the extracranial ICA dissecting aneurysm, the specimens were subjected to pathology studies. On initial evaluation, all of the patients had undergone conventional arteriography. Of the 15 patients with traumatic dissections who had follow-up angiograms, this consisted of intravenous (i.v.) digital subtraction angiography (DSA) in 2 patients and transfemoral conventional angiography in 13 patients (2 of whom had also undergone DSA). The interval from the initial to the last angiogram was 2 weeks to 3.5 years. Initial angiograms were done within hours of the accident in 11 cases, within days in 4 cases, within months in 2 cases, and within years in 4 cases (in these delayed cases neurologic manifestations had developed long after the
357 Table 1. Patients with traumatic or spontaneous extracranial inter-
Table 2. Frequency of symptoms and signs in 70 patients with
nal carotid artery (ICA) dissections
spontaneous and 21 patients with traumatic dissections of extracranial ICA
Data
Patient group Spontaneous
Traumatic
No. of patients
70 (29 M, 41 F)
21 (15 M, 6 F)
Patient age (years) Range Mean
18-76 41
19-55 32
Duration of follow-up Range Mean
22 months-9.5 years 64 months
4 days-7.5 years 40 months a
No. of patients with follow-up angiography (%)
42 (60)
15 (71)
a Excluding two patients who died 4 and 6 days after the accident as the result of massive cerebral infarct and edema
accident as the result of embo|ization from thrombi within the residual dissecting aneurysms). Of the 42 patients with spontaneous dissections who underwent follow-up angiography, this was a conventional arteriogram in 29 and i.v. DSA in 13. These had been carried out within 1 month to 6.5 years after the initial angiogram. The initial angiogram had been done within a few days after the onset of the symptoms in 62 cases and within 1 month in all but 3 cases. The X2 test and Fisher's exact test were used to evaluate the data.
Results
CIinical findings Spontaneous group. H e a d a c h e , the m o s t c o m m o n sympt o m (Table 2), was often unilateral (73%), and it was usually focal and located in the orbital, periorbital, and frontal regions. T h e o t h e r c o m m o n locations were mastoid region and d e e p in the ear, t e m p o r a l region, angle of the mandible, face, and finally occipital region. Focal cerebral ischemic s y m p t o m s [transient ischemic attack ( T I A ) and stroke] usually were d e l a y e d and followed a h e a d a c h e by a period ranging f r o m a few minutes to 2 weeks. A l t h o u g h the clinical picture varied and s o m e of the patients p r e s e n t e d with only focal ischemic events ( T I A , stroke, amaurosis fugax), or lower cranial nerve palsies, or h e a d a c h e and bruits, m a n y p r e s e n t e d with one o f the following distinct syndromes: hemicrania and o c u l o s y m p a t h e t i c palsy (OSP) (12 patients), hemicrania and delayed focal cerebral ischemic events (20 patients), and c o m b i n a t i o n of hemicrania, OSP, and focal cerebral ischemic events (15 patients). F o r t y p e r c e n t o f the patients were hypertensive and 16% had angiographic evid e n c e of fibromuscular dysplasia in carotid, vertebral, or renal arteries.
Traumatic group. Focal cerebräl ischemic symptoms were the m o s t c o m m o n of the clinical manifestations and often o c c u r r e d at s o m e time after the accident, sometimes m o n t h s or years (see the f o o t n o t e to Table 2). These de-
Symptom or sign
Headache Focal cerebral ischemic symptoms TIAs Stroke TIAS and stroke Oeulosympathetic paresis Bruits (subjective, objective, or both) Neck pain Light-headedness Syncope Amaurosis fugax Scalp tenderness Neck swetling Dysgeusia Lower cranial nerve palsies Asymptomatic° Sensation of pulsation in neck
Patient group Spontaneous
Traumatie
No.
%
No.
%
59 43
84 61
8 15 a
38 71 2 11 2
24 13 6 37
53
7
33
32 16 15 8 8 5 3 2 2 1 1
46 23 21
8 1b
38
2 1
1
Offen delayed after the accident: within 30min-12h, 6; within 4-20 days, 3; in 2 months, 1; after 6-10 years, 5 b Excluding any neck pain in connection with the original trauma c Symptoms related to a concomitant vertebral artery dissection TIA, Transient ischemic attack
layed ischemic s y m p t o m s were caused by e m b o l i z a t i o n f r o m t h r o m b i within the residual p o s t - t r a u m a t i c dissecting aneurysms as d e m o n s t r a t e d angiographically or by pathologic e x a m i n a t i o n of the excised dissecting aneurysms (Fig. 1). All patients had suffered m o d e r a t e to m a r k e d blunt t r a u m a , with m o t o r vehicle accident as the leading cause (62%). All but 3 patients had suffered other injury in addition to the I C A injury.
Angiographic findings These abnormalities (Table 3) have b e e n previously described by us and by others [5, 8, 10-14, 16, 19, 20]. T h e luminal stenosis was frequently irregular and often elongated and tapered. A n e u r y s m s were saccular or were elongated, ovoid, or finger-like. T h e u p p e r third of the extracranial I C A and subcranial region was the m o s t c o m m o n site, but the aneurysms also were seen frequently in the mid-third of the I C A and with a lesser f r e q u e n c y in the lower third of the I C A . Occlusions were often 2 3 cm distal to the carotid bifurcation and were usually tap e r e d to a point with a flame-like configuration. I C A dissection was bilateral in 20 patients (29%) in the spont a n e o u s g r o u p and in 8 patients (38%) in the traumatic group. C o n c o m i t a n t vertebral artery dissection was n o t e d in 3 patients in the s p o n t a n e o u s g r o u p and in 2 patients in the traumatic group.
358
Fig. 1. a Right carotid arteriogram demonstrates an elongated dissecting aneurysm (post-traumatic in this case). Contrast-filled true lumen is irregular due to filling of false lumen by thrombus. Also noted is a long intimal flap (arrows). b Cross section of a segment of the lesion demonstrates section through the internal carotid artery (ICA) and the related dissecting aneurysm. Note that the aneurysm is formed within the media. The external elastic lamina (thin arrows) surrounds both the true lumen of the ICA (asterisk) and the thrombus-filled false lumen of the aneurysm (FL). The false lumen has compressed the true lumen
(thick arrows)
Table 3. Angiographic findings in 90 ICAs (of 70 patients) with spontaneous dissection and 29 ICAs (of 21 patients) with traumatic dissection
t h o u g h o n l y 23% of the p a t i e n t s w e r e c o m p l e t e l y a s y m p tomatic.
Angiographic findings
Angiographic follow-up. In the s p o n t a n e o u s g r o u p , 52
Luminal stenosis Aneurysm Intimal flaps Slow ICA-MCA flow Occlusion Distal branch occlusions (emboli)
Patient group Spontaneous
Traumatic
No.
To
No.
%
69 35 25 22 15 11
77 39 28 24 17 12
13 17 7 3 8 3
45 59 24 10 28 10
MCA, Middle cerebral artery
d i s s e c t e d 1CAs (of 42 p ä t i e n t s ) w e r e r e s t u d i e d . O f 20 ane u r y s m s n o t e d in the initial a n g i o g r a m s , 6 r e m a i n e d unc h a n g e d , and 12 e i t h e r d e c r e a s e d in size o r r e s o l v e d (obl i t e r a t e d ) . O f the 40 s t e n o s e s , m o r e t h a n 87% e i t h e r c o m p l e t e l y o r p a r t i a l l y r e s o l v e d . O f 7 occlusions, o n l y 1 r e c a n a l i z e d , and the rest r e m a i n e d u n c h a n g e d . T w e n t y - t w o d i s s e c t e d I C A s (of 15 p a t i e n t s ) in the traumatic group were restudied angiographically. Only 3 of the 14 a n e u r y s m s n o t e d in the initial a n g i o g r a m dec r e a s e d in size or r e s o l v e d . A l s o , o n l y 6 o f the 11 s t e n o ses c o m p l e t e l y o r p a r t i a l l y r e s o l v e d , a n d 3 s t e n o s e s p r o g r e s s e d to occlusion. N o n e o f the 5 occlusions n o t e d initially r e c a n a l i z e d .
Follow-up
Treatment
Clinicalfollow-up. O f t h e s p o n t a n e o u s g r o u p , 76% w e r e a s y m p t o m a t i c , 1 d i e d o f u n r e l a t e d c a u s e ( c o l o n carcinom a ) , a n d o n l y 4 p a t i e n t s h a d m a r k e d o r m o d e r a t e deficits ( T a b l e 4). M i l d deficits o r r e s i d u a l r e c u r r e n t h e a d a c h e s w e r e p r e s e n t in 12% o f the p a t i e n t s . T h e h e a d aches w e r e s e v e r e in 2 p a t i e n t s . O v e r a l l , 59 p a t i e n t s ( 8 5 % ) m a d e c o m p l e t e o r e x c e l l e n t r e c o v e r i e s . O f the t r a u m a t i c g r o u p , 2 d i e d of m a s s i v e c e r e b r a l infarct and e d e m a a n d 4 h a d m o d e r a t e o r m a r k e d deficits. O v e r a l l , 71% h a d m a d e an e x c e l l e n t o r a c o m p l e t e r e c o v e r y , al-
D i f f e r e n t t r e a t m e n t m o d a l i t i e s h a d b e e n u s e d ( T a b l e 5) d e p e n d i n g u p o n the clinical m a n i f e s t a t i o n s , j u d g m e n t of the clinicians i n v o l v e d in the case, a n d the a m o u n t o f inf o r m a t i o n a v a i l a b l e at the t i m e r e g a r d i n g the n a t u r a l history of the disease. In the s p o n t a n e o u s g r o u p , a b o u t o n e - t h i r d r e c e i v e d no specific t r e a t m e n t . S e v e n p a t i e n t s h a d r e c e i v e d c o r t i c o s t e r o i d s p r i o r to t h e i r r e f e r r a l to us with the i m p r e s s i o n of " a r t e r i t i s " on the basis o f angiog r a p h i c findings of an i r r e g u l a r e l o n g a t e d s e g m e n t o f I C A . This t r e a t m e n t was t e r m i n a t e d in all 7. A c o n s i d e r -
359 Table 4. Follow-up in spontaneous and traumatic dissections of
ICA
Treatment modality
Patient group
Clinical follow-up Died Marked or moderate deflcits Mild deficitsa Mild or no deficits but residual headaches Asymptomatic Died of unrelated cause Angiographic follow-up
Spontaneous
Traumatic
No.
%
No.
%
0 4 7
0 6 10
2 4 6
10 19 29
5 53 1
7 76
4 5 0
19 24
(52 ICAs of 42 patients)
Aneurysm Eliminated by resection Unchanged Decreasedinsize Resolved Not visualizedb
20
Stenosis Resolution, complete Resolution, partial Progression ~ Progression to occlusion Elimination by resection Unchanged Occlusion Recanalization No change
40
14 4 5 2 1 2
29 36 14 7
4 2 1 3 1 0
36 18 9 27 9
11 23 58 12 30 2 5 2 5 0 1 5 1 6
Supportive only Anticoagulant therapy Antiplatelet therapy Surgery
No. of patients a Spontaneous
Traumatic
22 18 40
3 6 9 10~
9b
a Some patients received more than one of these modalities b Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass in 8 patients, ICA exploration in 1 patient « Resection and interposition graft in 5 patients, STA-MCA bypass ICA ligation in I patient, removal of MCA embolus and STAMCA bypass in 1 patient
(22 ICAs of 15 patients)
0 6 30 8 40 4 20 2
7
Table 5. Treatment modalities implemented in 70 patients with spontaneous and 21 patients with traumatic ICA dissections
0 5
a Not interfering with work or daily activities (i.e., slight paresis, mild sensory deficits, reflex asymmetries, slight dyscalculia, oeulosympathetic palsy, bruits) b As the result of ligation of parent vessel in one case and as the result of progression of stenosis to occlusion in the other cases c With additional appearance of a small aneurysm in the midsegment of extracranial ICA
ably larger proportion of the traumatic group had undergone operation, mostly consisting of resection of the residual aneurysm (considered to be the source of embolization) (Fig. 1). We now rarely operate on a patient with spontaneous I C A dissection. The indications and the rationale for surgical treatment in the traumatic group have been discussed in a previous publication [19].
Discussion
The clinical and angiographic features, as well as the outcome of spontaneous and traumatic I C A dissections, have been discussed in many papers [4, 10, 11, 13, 14, 18, 19, 24]. Traumatic dissections of the I C A resulting from blunt injuries are less common. Their clinical manifestations vary. In severe traumas, especially when the
patient is initially comatose or has suffered multiple organ injuries, traumatic I C A dissections may go undiagnosed. Patients who survive these severe traumas may have no neurologic deficits related to their undiagnosed I C A dissection or may have deficits that are often interpreted as related to "head injury" and thus angiography is not carried out. Some of these patients have residual traumatic dissecting aneurysms that may become symptomatic even years later by causing focal cerebral ischemic symptoms as the result of embolization from a thrombus within the aneurysm [19]. Spontaneous I C A dissections also may sometimes go undiagnosed because at times they may cause only mild or trivial symptoms or be entirely asymptomatic (for example, diagnosed incidentally during work-up of a patient with spontäneous vertebral artery dissection or the opposite I C A dissection). Symptoms delayed for years in spontaneous dissections, however, have been most unusual in our experience. A m o n g more than 100 cases of spontaneous I C A dissections seen by us, only 1 patient presented with symptoms due to embolization from a thrombus within a dissecting aneurysm, which was thought to have existed for years as the result of an undiagnosed spontaneous dissection (B. Mokri, unpublished data). Clinically, in the traumatic group the most c o m m o n picture was appearance of focal cerebral ischemic manifestations (TIAs or strokes) delayed from the accident for periods ranging from hours to years (Table 2). The most c o m m o n clinical pictures in the spontaneous group were hemicrania and Horner's syndrome (17%), or hemicrania and delayed focal cerebral ischemic manifestations (29%), or a combination of both (21%). Major clinical and angiographic features of the traumatic and spontaneous groups are compared in Table 6 and listed in decreasing order of statistical significance. However, it should be pointed out that, from the statistical point of view, the numbers, particularly of the traumatic group, are not large. It is possible that larger numbers could establish more or other significant differences. Cerebral ischemic events appeared to be somewhat more c o m m o n in the traumatic group, but not significantly so. Headaches (offen unilateral) were significantly more c o m m o n
360 Table 6. Major clinical and angiographic features and follow-up of
traumatic and spontaneous extracranial ICA dissections Feature
Patients or ICAs, % (no. involved/total no.) Spontaneous Traumatic
Death Headaches Asymptomatic at follow-up Stenosis Decrease in size or resolution of aneurysm at follow-up Partial or complete resolution of stenosis at follow-up Progression of stenosis to occlusion Aneurysm Marked or moderate deficit at follow-up Oculosympatheticpalsy Occlusion Residual recurrent hemicrania at follow-up Concomitant dissection of vertebralartery Focal cerebral ischemic events Bilaterality Bruits
P
0 (0/70) 84 (59/70) 76 (53/70) 77 (69/90)
10 (2/21) 38 (8/21) 24 (5/21) 45 (13/29)
