Endovascular Stenting of an Acutely Thrombosed Basilar Artery: Technical Case Report and Review of the Literature Constantine C. Phatouros, M.B.B.S., F.R.A.C.R., Randall T. Higashida, M.D., Adel M. Malek, M.D., Ph.D., Wade S. Smith, M.D., Ph.D., Thaddeus W . Mully, M.D., Stephen J. DeArmond, M.D., Ph.D., Christopher F. Dowd, M.D., Van V. Fialbach, M.D. Department of Radiology, Division of Interventional Neurovascular Radiology (CCP, RTH, AMM, CFD, W H ) , and Departments of Neurological Surgery (RTH, CFD, W H ) , Neurology (WSS), and Neuropathology (TW M , S)D), University of California San Francisco Medical Center, San Francisco, California dolichoectasia, aneurysm formation, and dissection. Patients presenting with symptoms of ischemia referable to ath­ erosclerotic basilar artery stenosis are An 83-year-old man with a prior his­ tory of hypertension, coronary artery dis­ ease, and hypercholesterolemia presented with a 6-day history of headaches and presyncopal episodes. A few days later he experienced two episodes, each lasting a few hours, of a fluctuating locked-in state associated with bilateral facial weakness, quadriparesis, and bilateral limb pares­ thesia. C onsciousness was preserved throughout, suggesting preservation of midbrain perfusion. The patient sponta­ neously recovered from these episodes, with residual mild dysarthria and mini­ mal right-sided hemiparesis. Magnetic resonance imaging scans demonstrated intraluminal thrombus within both distal vertebral arteries, extending into the prox­ imal basilar artery. A small area of accom­ panying signal alteration, consistent with ischemia, was present in the left ventral N eurosurgery, Vol. 44> No. 3, M arch 1999 667 KeV words: Atherosclerosis, Balloon angioplasty, Thrombolysis, Vertebrobasilar insufficiency T h e basilar artery is frequently a site the development of atheromatous plaque (19). The clinical sequelae lnclude ischemia, thromboembolisms, CASE REPORT Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 OBJECTIVE AND IMPORTANCE: The goal of this report was to describe the successful percutaneous endovascular use of a Gianturco-Roubin-2 cor­ onary stent in the treatment of an acute atherothrombotic occlusion of the basilar artery. To our knowledge, the percutaneous endovascular deployment of an intra-arterial stent for the treatment of an acute athero­ thrombotic occlusion of the basilar artery and the percutaneous endo­ vascular placement of a Gianturco-Roubin-2 stent in the basilar artery have not been previously reported. CLINICAL PRESENTATION: An 83-year-old man presented with a recurrent, transient, locked-in syndrome resulting from a lower basilar artery oc­ clusion caused by vertebrobasilar thrombosis superimposed on severe proximal basilar artery atheromatous stenosis. INTERVENTION: After successful superselective intra-arterial thrombolysis of the vertebrobasilar clot, balloon angioplasty of the underlying basilar artery stenosis was performed, without significant angiographic improve­ ment. Percutaneous endovascular deployment of a Gianturco-Roubin-2 coronary stent of 4-mm diameter was subsequently performed, with excellent angiographic results. CONCLUSION: The patient made a very good neurological recovery but unfortunately died as a result of cardiogenic shock and sepsis. Detailed neuropathological follow-up results are presented; stent patency was revealed in the postmortem examination. The anatomic and pathophys­ iological considerations of basilar artery stent placement for the treat­ ment of acute basilar artery occlusion related to atherosclerotic stenosis 3re discussed. (N e u ro su rg e ry 4 4 : 6 6 7 - 6 7 3 , 1 9 9 9 ) usually initially treated medically using antiplatelet agents and/or anticoagula­ tion therapy. For the subset of patients for whom medical management fails and for those who present with basilar artery occlusion as an emergency, the therapeutic options are limited. The re­ sults of surgical bypass grafting for basi­ lar artery narrowing or occlusion are disappointing (25), especially if the grafting is performed during an episode of ischemia. Successful transluminal an­ gioplasty of the basilar artery was first reported in 1980 by Sundt et al. (25); however, the body of data remains small. When angioplasty is unsuccessful in relieving stenosis, the treatment op­ tions are essentially exhausted. Endo­ vascular stent placement has been suc­ cessfully used in the treatment of atheromatous plaque in the coronary and peripheral arteries, and a recent re­ port described the first successful percu­ taneous endovascular deployment of a stent within the basilar artery (15). We demonstrate the technical feasibility of endovascular stent deployment for the treatment of basilar artery atherosclero­ sis with acute thrombosis, and we dis­ cuss the relevant clinicopathological considerations. 668 Phatouros et al medulla. A cerebral angiogram confirmed bilateral distal vertebral artery occlusions above the level of the posterior inferior cerebellar arteries, with reconstitution of the rostral basilar artery via a right poste­ rior inferior cerebellar artery to right an­ terior inferior cerebellar artery collateral anastomosis (Fig. 1). The vertebral arteries were codominant, of good caliber, and free of significant atherosclerotic disease in their extracranial portions. There was a A narrow left and an absent right posterior communicating artery. At presentation, the patient was alert and orientated, with normal mental state examination findings. Cranial nerve ex­ am ination results w ere u nrem arkable except for mild dysarthria; however, pal­ atal movement was normal. Visual field testing yielded normal findings. There was very mild right hemiparesis (5-/5) with a right pronator drift. Plantar re­ sponses were downgoing. Sensory and coordination examination results were normal. The patient was transferred to our institution for emergency superse­ lective intra-arterial thrombolysis. Nl B TECHNICAL SUMMARY FIGURE 1. A, anteroposterior view of the posterior fossa during a right verte­ bral artery injection, showing reconsti­ tution of the upper basilar artery via a right posterior inferior cerebellar artery-anterior inferior cerebellar artery anastomosis (arrow). B, lateral view of the posterior fossa during a left verte­ bral artery injection, showing complete occlusion of the left vertebral artery above the posterior inferior cerebellar artery origin (arrow), with no basilar artery reconstitution. Neurosurgery, Vol. 44, No. 3, March 1444 i A FIGURE 2. A, selective microcatheter injection showing anterograde flow within the basilar artery after local infusion of 7 5 0 ,0 0 0 units of UK and revealing underlying proximal basilar artery stenosis (open arrow). B, antero­ posterior view of the posterior fossa after local infusion of 975 ,00 0 units of UK. There has been rethrombosis of the proximal basilar artery, with conse­ quent weak filling distally. tional 125,000 units were infused. After the administration of a total of 975,000 units of UK, there was only j weak anterograde basilar artery flow via the left ver­ tebral artery because rethrombosis at the site of basilar artery stenosis had occurred (Fig. 2B). It was also noted that a small hematoma was accumulating at the site ot the previous right femoral artery punC* ture, necessitating the immediate apphca“ tion of a FemoStop compression devio (Radi Medical Systems, Uppsala, Swe­ den), which remained in place for the rt mainder of the procedure. Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 B Cerebral angiography performed im­ mediately after arrival at our institution demonstrated findings similar to the previous angiogram (see above). Care was taken to ensure that the right fem­ oral artery puncture was below the level of the inguinal ligament, because of the possibility of thrombolytic therapy. General anesthesia was administered, and the patient underw ent full heparinization (activated clotting time, >250 s), using an intravenously administered load­ ing dose followed by a continuous intra­ venous heparin infusion. A 7-French guide catheter was selectively placed into the proximal left vertebral artery. A Rapid Transit microcatheter (Cordis Endovascu­ lar, Miami Lakes, FL) primed with an 0.014-inch steerable guidewire was ad­ vanced into the distal left vertebral artery, immediately proximal to the occlusive thrombus, and local thrombolytic therapy using urokinase (UK) was commenced. After infusion of 750,000 units of UK, there was substantial lysis of the proximal clot and reestablishment of anterograde basilar artery flow via the left vertebral artery, revealing severe underlying steno­ sis (14.5-mm length) of the basilar artery commencing at the vertebrobasilar junc­ tion and extending rostrally (Fig. 2A). The normal basilar artery diameter at its mid■/ point was approximately 3.6 mm. The mi­ crocatheter and guidewire were carefully advanced through this stenosis into the distal basilar artery clot, and an additional 100,000 units of UK were infused. The microcatheter was then retracted into the distal left vertebral artery, and an addi- Basilar Stent an g io p la sty of tw o m o d e ra te ly sev ere a th e ro s c le ro tic le sio n s b e tw e e n th e v e r ­ te b ro b a sila r ju n ctio n a n d th e o rig in o f th e left p o s te r io r in fe rio r c e r e b e lla r a r ­ tery w a s u n d e rta k e n , w ith sa tisfa cto ry r e s u l t s . Figure 4 s h o w s t h e f i n a l a n g i o ­ g ra p h ic resu lt, w ith a b asilar a rte ry o f n o rm a l ca lib e r a n d p a te n cy o f b o th v e r­ teb ral a rte rie s. T h e re w a s e v id e n c e o f sm all d ista l-b ra n ch o cclu sio n s w ith in th e rig h t a n te rio r in ferio r ce re b e lla r a r­ tery a n d b o th p o ste rio r ce re b ra l a rte ry territo ries. T h e r ig h t f e m o r a l s h e a t h w a s le ft in p la ce , a s w a s th e F e m o S to p d e v ice , m a in ­ ta in in g c o n s ta n t p re s s u re o n th e p re v io u s a rte ria l p u n c t u r e site. T h e r e w a s n o e v i­ d e n c e , h o w e v e r, o f a sig n ifican t g ro in h e ­ m a to m a , a n d h e m a to crit v alu es re m a in e d stab le fo r th e n e x t fe w d a y s. In tra v e n o u s h e p a rin tre a tm e n t w a s co n tin u ed , m a in ­ ta in in g th e a ctiv a te d p artial th ro m b o p la s ­ tin tim e b e tw e e n 5 0 a n d 8 0 s e c o n d s . T re a tm e n t w ith a sp irin (3 2 5 m g d aily ) a n d ticlo p id in e (2 5 0 m g tw ice e a ch d a y ) w a s c o m m e n c e d . T h e p atien t w a s tra n s­ fe rre d to th e n e u ro in te n s iv e c a re u n it w h ile in tu b a te d . C L IN IC A L O U T C O M E T h e p atien t u n d e rw e n t e x tu b a tio n 24 h o u rs later b u t re q u ire d re in tu b a tio n s o o n after b e c a u s e o f p u lm o n a ry e d e m a re su lt­ in g fro m c a rd ia c failu re. N e u ro lo g ic a l e x ­ a m in a tio n resu lts w e re n o rm a l e x c e p t fo r m in im a l p re -e x istin g rig h t h e m ip a re sis, w h ich h ad n o t w o rse n e d . E y e m o v e ­ m e n ts , v isu a l field s, a n d p a la te a n d to n g u e m o v e m e n ts rem ain ed n o rm al; h o w e v e r, th e p a tie n t h a d a cq u ire d s o m e p h a ry n g e a l d y sm o tility , w h ich m a y h a v e b e e n th e re su lt o f e n d o tra c h e a l in tu b atio n . P h a ry n g e a l fu n ctio n sig n ifica n tly im ­ p ro v e d d u rin g th e n e x t fe w d a y s , a n d th e n e u ro lo g ica l sta tu s o f th e p a tie n t re ­ m a i n e d s ta b le . H is c o u r s e in th e in te n s iv e ca re u n it w a s c o m p lic a te d b y a p e rip ro c e d u ra l m y o c a rd ia l in farctio n (re su lt­ in g in c a r d ia c fa ilu re a n d p u l m o n a r y e d e m a ) a n d p n e u m o c o c c a l sep sis. T h e p a ­ tien t re fu s e d in v a s iv e c a rd io lo g ic a l th e r­ a p y a n d , in v i e w o f o n g o i n g c o r o n a r y isch e m ia , tissu e p la s m in o g e n a c tiv a to r w a s a d m in is te re d in tra v e n o u s ly o n th e se v e n th p o sto p e ra tiv e d a y . T h is p re cip i­ ta te d a n a c u te d e c r e a s e in th e h e m a to c r it v a lu e , as a resu lt o f a re tro p e rito n e a l h e ­ m a to m a n ecessitatin g b lo o d tran sfu sio n . T h e p a tie n t d ie d o n th e ten th p o s to p e ra ­ tiv e d a y a s a re su lt o f se p sis a n d in tra c ta ­ b le c a rd ia c failu re le a d in g to c a rd io g e n ic shock. P A T H O L O G I C A L R ESU LTS IGURE 3. Anteroposterior view show­ ing residual underlying severe proximal asilar artery stenosis after thrombolySls and angioplasty. FIG U RE 4. Anteroposterior view show­ ing the final angiographic appearance after stent deployment within the proxi mal basilar artery and angioplasty of the distal left vertebral artery (small arrows, proximal and distal ends of the stent). The distal stent margin is just beneath the left anterior inferior cere­ bellar artery origin. The proximal stent margin extends a few millimeters into the left vertebral artery, partially cover ing the right vertebral artery outflow. Neurosurgery, Vol. 44, No. 3, March / 999 P o stm o rte m ex a m in a tio n w a s p e r­ fo rm e d a p p ro x im a te ly 15 h o u rs after d e a t h , 10 d a y s a f t e r t h e p l a c e m e n t o f t h e b a sila r a rte ry sten t. G ro s s e x a m in a tio n o f th e b a s ila r v e s s e ls re v e a le d a m e ta llic co il s te n t w ith in th e left v e r te b r a l a n d b a s ila r arteries. T h e ste n t e x te n d e d 3 m m in to th e d is ta l e n d o f th e left v e r te b r a l a r te r y a n d o c c u p ie d tw o -th ird s o f th e le n g th o f th e b a s i l a r a r t e r y (Fig. 5 ) . T h e d i s t a l v e r t e b r a l arteries a n d b asilar a rte ry w e re p aten t. A t h e r o s c l e r o t i c p l a q u e s m e a s u r i n g 0.5 a n d 1.0 c m i n g r e a t e s t d i m e n s i o n w e r e n o te d ro stra l a n d c a u d a l to th e ste n t, re ­ s p e c tiv e ly . T h e s e re s u lte d in a s y m m e tr ic circu m feren tial lu m in al n a rro w in g . H e m ­ o rrh a g e w a s n o te d w ith in th e w a ll o f th e b asilar a rte ry , o v e r th e ro stral p la q u e . M i­ cro sco p ic e x a m in a tio n o f th e v e rte b ra l a n d b asilar arteries re v e a le d se v e re a th ­ ero sclero sis w ith re ce n t h e m o rrh a g e b e ­ tw e e n th e a th e ro m a to u s p la q u e s a n d th e Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 W ith th e tip o f th e m i c r o c a t h e t e r d is ta l to th e b a s i l a r a r t e r y s t e n o s i s , a 0 . 0 1 4 - i n c h , 300-cm , e x c h a n g e g u id e w ir e (S ta b iliz e r; C o rd is E n d o v a s c u l a r ) w a s p l a c e d in th e d istal left p o s t e r i o r c e r e b r a l a r t e r y . A c o r ­ on ary b allo o n a n g io p la s ty c a th e te r (V a lo r; C o rd is E n d o v a s c u la r ) w ith a n o m i n a l b a l­ lo o n d i a m e t e r o f 3 .5 m m a n d a l e n g t h o f 20 m m w a s t h e n p o s i t i o n e d a c r o s s t h e b asilar a r t e r y s t e n o s i s . T w o b r i e f b a l l o o n d ilatio n s w e r e p e r f o r m e d ( w i t h a n i n t e r ­ v en in g a n g io g r a p h ic r u n ), to p r e s s u r e s o f 6 atm o sp h e re s (e q u iv a le n t to a 4 - m m d i­ a m e t e r i n v i t r o ) . Figure 3 s h o w s t h e f i n a l p o stan g io p lasty re su lts, w ith s e v e r e re s id ­ ual b asilar a r te r y s te n o s is . In v ie w o f th e r e f r a c t o r y n a t u r e o f th is p laq u e a n d th e s t r o n g lik e lih o o d o f r e ­ t h r o m b o s i s if n a r r o w i n g w a s n o t r e l i e v e d , a b a l l o o n - m o u n t e d , G i a n t u r c o - R o u b i n -2 coron ary sten t (C o o k C a r d io lo g y , B lo o m ­ in g to n , IN ), m e a s u r i n g 4 m m in d i a m e t e r a n d 20 m m i n l e n g t h , w a s s l o w l y a n d carefu lly a d v a n c e d a l o n g t h e g u i d e w i r e and p o sitio n ed a c ro s s th e s te n o tic lesio n . The b allo o n w a s in fla te d to a p r e s s u r e o f 6 atm o sp h eres (r e c o m m e n d e d in fla tio n p ressu re), r e s u ltin g in s a tis f a c to r y a n d u n ­ ev en tfu l s te n t d e p l o y m e n t . T he b allo o n w a s c a re fu lly w ith d r a w n in to th e d i s t a l le f t v e r t e b r a l a r t e r y , t a k ­ in g c a r e n o t t o d i s l o d g e t h e s t e n t , a n d 669 670 Phatouros et al FIG U RE 6. Photomicrograph of the midbasilar artery, showing eccentric atherosclerotic plaque with hemorrhage (iatrogenic) between the plaque and the vessel wall (arrow). m u scu la ris, co n siste n t w ith m e ch a n ica l d is ru p tio n o f th e a th e ro scle ro tic p la q u e at t h e t i m e o f s t e n t p l a c e m e n t (Fig. 6) . C o ro n a l se ctio n s o f th e b ra in re v e a le d m u ltip le a re a s o f d isco lo ra tio n co n sisten t w ith h e m o rrh a g ic in farctio n s. T h e s e a re a s w e r e n o t e d in th e r ig h t p a r i e t o - o c c i p i t a l re g io n a n d w ith in th e rig h t o ccip ital p o le, in th e d is tr ib u tio n o f th e r ig h t p o s t e r i o r c e r e b r a l a r te r y . T h e la r g e s t w a s a 1 .5 - X 1.0- c m h e m o r r h a g e t h a t i n v o l v e d t h e i n ­ f e r i o r 20% o f t h e v i s u a l r a d i a t i o n s a n d a d ja ce n t o ccip ita l c o rte x . B ilateral s u p e ­ rio r ce re b e lla r le sio n s th at w e r e a p p r o x i­ m a t e l y 1.0 c m i n g r e a t e s t d i m e n s i o n a n d co n sisted of m u ltip le p e te ch ia e w e re p r e s e n t . In t h e p o n s , f o u r p e t e c h i a e o f 0 .2 t o 0 .3 c m in g r e a t e s t d i m e n s i o n w e r e lo ­ D IS C U S S IO N A s early as 1934, L h e rm itte an d T r e l l e s (1 7 ) n o t e d th a t, o f all o f t h e c e r e ­ b ral v e sse ls, th e b a sila r a rte ry w a s m o s t c o m m o n ly affected b y a th e ro scle ro sis. In o n e o f th e l a r g e s t s e r i e s o f its k i n d , F i s h e r e t a l. ( 1 2 ) in 1 9 6 5 , a f t e r e x a m i n i n g th e in tra cra n ia l a n d e x tra c ra n ia l c e re ­ b r a l v a s c u l a t u r e in 1 7 8 r o u t i n e a u t o p s y c a s e s , c o n c lu d e d th at th e b a sila r c o n flu ­ e n c e w a s a site o f p re d ile c tio n fo r a th ­ Neurosurgery, Vol. 44, No. j, March / 999 % t h r o m b o t i c a n d 7 a s e m b o l i c . T h e em boh s o u r c e w a s c a r d i a c i n f o u r c a s e s (thret c a s e s o f s u b a c u t e b a c t e r i a l e n d o c a r d i t i s aru o n e o f a t r i a l f i b r i l l a t i o n ) , t h e r e w a s a s i n g *1 u n u s u a l c a s e o f a t u m o r e m b o l u s o rigin ^ Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 FIG U RE 5. Photograph of the basilar artery in the postmortem examination. The stent can be clearly observed through the thin basilar artery wall (arrows). Note the relative wide spac­ ing of the stent struts and extensive atherosclerotic disease. The distal stent margin is just beneath the left anterior inferior cerebellar artery origin, and this correlated with the junction of the superior two-thirds and inferior onethird of the pons in the gross specimen. c a t e d in th e r ig h t b a s e . In th e m e d u l l a , a 0 .5 - c m h e m o r r h a g i c le s io n w a s l o c a t e d in th e rig h t d o rso la te ra l te g m e n tu m . M icro sco p ic e x a m in a tio n o f th e b rain , ce re b e lla r, a n d p o n tin e lesio n s d e m o n ­ s t r a te d in f a r c tio n s 1 .5 to 2 w e e k s o f a g e , c o r r e s p o n d in g to th e tim e o f th e clin ical lo ck e d -in e p iso d e s a n d sten t p la ce m e n t. M i c r o s c o p i c a l l y , th e h e m o r r h a g e in th e rig h t d o rso la te ra l te g m e n tu m o f th e m e ­ d u lla w a s a sso cia te d w ith m o re e x te n siv e in farctio n o f th e m e d u lla . T h is in farctio n e x te n d e d fro m th e p o s te rio r e d g e o f th e rig h t p y r a m id to th e h y p o g lo s s a l n u c le u s a n d la te ra lly to th e rig h t v e s tib u la r n u cle i a n d d e s c e n d i n g s p in a l tr ig e m in a l tra c t. In a d d itio n to a b u n d a n t v a s c u la r p ro life ra ­ tio n , th e re w a s a n e x u b e r a n t m a c r o p h a g e re s p o n s e , in d ic a tin g th a t th is le sio n w a s u p to 1w e e k o ld e r a n d th e re fo re p re d a te d th e in te rv e n tio n . M o st o f th e in fa rctio n s w e re clin ically s ile n t, p a r t i c u l a r l y t h o s e in th e c e r e b e l ­ lu m . N o le sio n w a s fo u n d to e x p la in th e m in o r rig h t h e m ip a re s is n o te d b e fo re sten t d e p lo y m e n t. e r o s c l e r o s i s . T h e y o b s e r v e d t h a t th e l o w e r p a r t o f t h e b a s i l a r a r t e r y , a t th e c o n f l u e n c e o f t h e v e r t e b r a l a r te r ie s , w as t h e p r i m a r y s i t e o f a f f l i c t i o n i n t h e early s t a g e s o f a t h e r o m a f o r m a t i o n a n d th at th is p a t t e r n o f d i s t r i b u t i o n rem ain ed c o n s t a n t a s t h e a t h e r o s c l e r o t i c d isease p r o g r e s s e d . I n t h e p r o x i m a l b a s i l a r ar­ t e r y , a t h e r o s c l e r o s i s w a s m o r e s e v e r e on t h e s i d e o f t h e l a r g e r v e r t e b r a l a r t e r yJ a n d i n v o l v e d t h e c o r r e s p o n d i n g h a l f of t h e p e r i m e t e r o f t h e b a s i l a r a r t e r y (the i n t r a c r a n i a l p o r t i o n o f t h e d o m i n a n t ver­ t e b r a l a r t e r y w a s u s u a l l y m o r e severely a f f e c t e d ) . T h o s e a u t h o r s a l s o n o t e d a stron g a s s o c i a t i o n b e t w e e n h y p e r t e n s i o n a n d th e s e v e r i t y o f a t h e r o s c l e r o t i c d i s e a s e i n th e v e r t e b r o b a s i l a r s y s t e m . I n t h e i r series, t h r o m b o t i c o c c l u s i o n s o f t h e l a r g e r in tra­ c r a n i a l a r t e r i e s w e r e l i m i t e d t o t h e verte­ b r o b a s ila r s y s t e m a n d w e r e u s u a lly sym p­ t o m a t i c , i n c o n t r a s t t o e x t r a c r a n i a l verteb ral a r t e r y o c c l u s i o n s , w h i c h w e r e u su ally asy m p to m atic. E i g h t y e a r s l a t e r , C a s t a i g n e e t a l . (7 ), n o t i n g th e r e l a t i v e s c a r c i t y o f p o stm o r­ t e m d a t a r e g a r d i n g t h e p a t t e r n s o f oc­ c l u s i o n s i n t h e v e r t e b r o b a s i l a r s vj s t e m , i n a n 8- y e a r p e r i o d c o l l e c t e d 4 4 p o s t ­ m o r t e m s p e c i m e n s d e m o n s t r a t i n g ver­ t e b r o b a s i l a r s y s t e m o c c l u s i o n s . I n th eir s e r i e s t h e r e w e r e 1 8 b a s i l a r a r t e r yj o c c l u s i o n s , o f w h i c h 1 7 ( 9 4 % ) w e r e t h e result o f a t h e r o s c l e r o t i c t h r o m b o s i s ; t h e oth er w a s t h e r e s u l t o f a c a r d i a c e m b o l u s re­ l a t e d t o a t r i a l f i b r i l l a t i o n . A m o n g this g r o u p o f 1 7 p a t i e n t s w i t h ath ero sclero sisr e l a t e d t h r o m b u s , a n o c c l u s i v e th rom b u s d e v e l o p e d o v e r p r e - e x i s t i n g b a s i l a r artery s t e n o s i s f o r 1 4 ( 7 8 % ) , a p r i m a r y ath ero­ s c l e r o t i c l e s i o n w a s s i t u a t e d i n t h e d istal v e r t e b r a l a r t e r y f o r 2, a n d a n a t h e r o s c l e ­ r o t i c b a s i l a r a r t e r yy a n e u r yr s m w a s ob s e r v e d f o r 1. B e f o r e t h i s , t h e l a r g e s t s e r i e s o f this k i n d w a s t h e m i l e s t o n e r e p o r t b y K u b ik a n d A d a m s ( 1 6 ) p u b l i s h e d i n 1 9 4 6 , w h ich r e p r e s e n t e d t h e f i r s t comprehensive d in * i c o p a t h o l o g i c a l d e s c r i p t i o n s o f b a s ila r ar­ t e r y ’ t h r o m b o s i s . F o r t h e i r s e r i e s o f 1 8 c a se s, tid s o m e o f w h i c h w e r e e x a m i n e d i n lite aIU a ll o f w h i c h w e r e e x a m i n e d in au to p sies t h e y r e p o r t e d 11 ( 6 1 % ) o c c l u s i o n s as Basilar Stent O f in te re st in th is r e g a r d a r e th e r e ­ cent g ro w in g a w a r e n e s s a n d u n d e r ­ stan d in g o f th e ro le p la y e d b y h e m o d y ­ n a m ic fa c to rs in th e p a t h o g e n e s i s o f ath ero sclero sis. A lth o u g h a n e x te n s iv e r e v i e w is b e y o n d t h e s c o p e o f t h i s a r t i ­ c l e , it is b e c o m i n g i n c r e a s i n g l y w e l l r e c ­ o g n ized th a t a th e r o s c le r o s is h a s a p r o ­ p en sity to d e v e l o p in th e r e g i o n o f th e v essel w a ll e x p o s e d to l o w s h e a r s tr e s s cln d c o m p l e x f l o w p a t t e r n s ( 6 , 1 3 ) . M u c h o t th is w o r k h a s f o c u s e d o n t h e d i s t r i ­ b u tio n o f p l a q u e s a t a r t e r i a l b i f u r c a ­ tio n s. I n t e r e s t i n g l y , t h e b a s i l a r a r t e r y is | c o n ly la rg e a r te r y in h u m a n s u b je c ts i lX e r e t w o f l o w s m e r g e ; i n t h i s p a r t i c u ­ lar a n a to m ic a r r a n g e m e n t, th e lo w -w a ll s h e a r th e o ry p re d ic ts th e d e v e lo p m e n t o f p la q u e n e a r th e a p e x a n d a t b o th lateral w a lls o f th e b a sila r c o n flu e n c e ( 22) , a p r e d i c t i o n s t r i k i n g l y i n a c c o r ­ d a n c e w ith th e a fo re m e n tio n e d p a th o ­ lo g ical d a ta . T h e d ia g n o sis o f b asilar a rte ry o c c lu ­ sio n p o rte n d s a g ra v e p ro g n o sis. W h e n th is c o n d i t i o n is u n t r e a t e d th e m o r t a l i t y r a t e i s g r e a t e r t h a n 7 0 % ( 2, 3 , 7, 8 , 1 1 , 1 6 ) . D e sp ite th e in cre a se d tim e u su a lly co n sid ­ e re d to b e a v a ila b le b e tw e e n th e o n s e t o f ictu s a n d th e in itiatio n o f th ro m b o ly s is (c o m p a re d w ith an terio r cereb ral circu la­ tio n stro k e ) a n d th e a d v e n t o f m o d e m su p e rse le ctiv e th ro m b o ly tic tech n iq u es, d e a t h is still a p r o b a b l e o u t c o m e (4 , 9 , 1 4 , 2 6 ). A r e c e n t r e t r o s p e c t i v e s t u d y in w h i c h 20 p a t i e n t s w i t h a n g i o g r a p h i c p r o o f o f b asilar a rte ry th ro m b o sis w e re treated w ith lo cal U K th e ra p y re p o rte d a m o rta l­ i t y r a t e o f 6 5 % a t 3 m o n t h s ( 8). O t h e r rep o rts h a v e p ro v id e d s o m e w h a t g reater e n c o u ra g e m e n t, g e n e ra lly co rre la tin g th e p re s e n c e o f p a te n t a rte rie s after tre a tm e n t w ith s u r v iv a l ( 4 ,1 4 , 2 6 ). In th e p r e v io u s ly c ite d s t u d y o f C r o s s e t al. (9 ), c o m p l e t e r e c a n a liz a tio n w a s a c h i e v e d in o n e -h a lf o f th e ca se s a n d 6 0 % o f th ese p a tie n ts s u r­ v iv e d , a lth o u g h o n ly o n e-th ird a ch ie v e d a " g o o d " n e u ro lo g ica l o u tc o m e (m o d ified R a n k in sco re o f 0 - 2 a n d B arth el In d e x s c o re o f 9 5 -1 0 0 ). In th a t s tu d y th e b e st p re d ic to rs o f s u rv iv a l w e r e d istal clo t lo ­ ca tio n a n d c o m p le te re can alizatio n . T h e su rv iv a l ra te for th e g ro u p w ith p ro x im a l o r m id b a sila r clo ts w a s o n ly 1 5 % . A p o s ­ sib le e x p la n a tio n fo r th e se fin d in g s, as o f f e r e d b y t h e a u t h o r s , is t h a t d i s t a l c l o t s a re m o re o ften e m b o lic a n d h e n ce m a y b e m o r e a m e n a b l e to ly s is t h a n is t h r o m b u s s u p e rim p o s e d o n p re -e x istin g a th e ro scle ­ r o s i s , w h i c h m a y b e p r o n e t o r e c u r ( a s it d id in tw o o f th e ir c a s e s ). S im ila rly , B r a n d t e t al. (4 ), in a r e t r o s p e c t i v e s t u d y o f 51 p a tie n ts w ith a cu te b asilar a rte ry o cclu ­ sio n tre a te d w ith lo cal th ro m b o ly tic th e ra p y , re p o rte d a lo w re ca n a liz a tio n fre­ q u e n cy (1 9 % ) a m o n g th o se w ith ath ero th ro m b o tic o cclu siv e d ise a se , n o tin g th at sig n s o f su b co rtica l a rte rio scle ro tic arterio p a t h y in c o m p u t e d t o m o g r a p h i c s c a n s w e re co rrelated w ith n o n recan alizatio n . T h e su rv iv a l rate for p a tie n ts w ith a th e ro t h r o m b o t i c d i s e a s e w a s o n l y 6% a n d t h a t fo r th o s e w ith c a u d a l o c c lu s io n sites (in ­ fe rio r to th e a n te rio r in fe rio r ce re b e lla r Neurosurgery, Vol. 44, No. 3, March 1999 a r t e r y o r i g i n ) w a s 1 3 % . In th a t s t u d y , a g e w a s a lso id en tified a s a n in d e p e n d e n t c o ­ v a ria b le a sso cia te d w ith a th e ro th ro m b o tic o cclu sio n ; th e o ld e st s u rv iv in g p a tie n t for w h o m recan alizatio n w a s a ch ie v e d w a s 6 3 y e a rs o f ag e. O u r p atien t w a s 8 3 y e a rs o f ag e. B e ca u se m o s t stu d ie s stress th e i m p o r t a n c e o f a c h i e v i n g r e c a n a l i z a t i o n , it s e e m s lik ely th a t sa fe a n d e ffe ctiv e m e th ­ o d s o f treatin g u n d e rly in g a th e ro scle ro tic s t e n o s i s a r e d e s i r a b l e if p a t i e n t o u t c o m e s a re to b e im p ro v e d . In o u r p a tie n t th e r e w a s u n d e r ly in g ste n o sis o f th e p ro x im a l b asilar a rte ry , w h ich ca u se d re th ro m b o sis after re c a n ­ a liz a tio n h a d b e e n in itially a c h ie v e d w ith lo cal th ro m b o ly s is . B a llo o n a n g io ­ p la sty w a s n o t su ccessfu l (d e sp ite d ila­ tio n to a d ia m e te r o f 3 .5 m m ) , a n d th e r e ­ fore sten t p la ce m e n t w a s re g a rd e d as th e o n ly re m a in in g th e ra p e u tic o p tio n . T h e d a ta re g a rd in g th e u se o f ste n ts w ith in th e v e rte b ra l a rte rie s fo r th e t r e a t m e n t o f a t h e r o m a t o u s n a r r o w i n g is s p a r s e ( 10, 21, 2 4 ) . S t o r e y e t a l . ( 2 4 ) f i r s t re p o rte d th e su cce ssfu l u se o f ste n ts fo r th e tre a tm e n t o f a th e ro scle ro tic n a r r o w ­ in g o f th e v e r te b r a l a r te r y o r ig in in th r e e p a tie n ts . A r e p o r t b y P io tin e t al. (2 1 ), in w h ic h fiv e p a tie n ts u n d e r w e n t e n d o v a s ­ cu lar p la ce m e n t of b a llo o n -e x p a n d a b le c o ro n a ry sten ts for s y m p to m a tic v e r­ teb ral a rte ry ste n o se s, d e s c rib e d sa tis­ fa cto ry a n g io g ra p h ic resu lts w ith re s­ o lu tio n o f s y m p t o m s fo r all p a tie n ts at 1 4 -m o n th fo llo w -u p e x a m in a tio n s. H i g a s h i d a e t al. (1 5 ) r e p o r t e d th e firs t clin ical u se o f a ste n t (P a lm a z -S c h a tz ; Joh n son an d Joh n son In terv en tio n al S y s t e m s , W a r r e n , N J ) in th e b a s ila r a r ­ te ry ; h o w e v e r , th is w a s fo r th e tre a t­ m e n t of a ru p tu re d fu sifo rm a n e u ry s m , w ith th e ste n t p rim a rily a ctin g as a s c a f­ fo ld to s u p p o r t e n d o a n e u r y s m a l, e le ctro ly tica lly d e ta c h a b le co ils. S e k h o n et al. (2 3 ) r e c e n tly r e p o r t e d a s im ila r p r o ­ c e d u re for th e tre a tm e n t o f a w id e ­ n e ck e d a n e u ry s m a risin g fro m th e in tra ­ cran ial v e rte b ra l a rte ry . W e c h o s e to u s e a c o r o n a r y s te n t b e ­ c a u s e h i g h in tr in s ic s t e n t f le x ib ility is n e c e s s a ry fo r th e sa fe a n d reliab le n a v ­ ig a tio n o f th e to rtu o sitie s o f th e v e rte ­ b r a l a r t e r y . T h e G i a n t u r c o - R o u b i n -2 i s a p re lo a d e d , b a llo o n -e x p a n d a b le sten t m a d e o f sta in le ss steel. W h e n d e p lo y e d , th e ste n t in te rstice s a re re la tiv e ly w id e ­ s p a c e d (th is c a n b e c le a r ly s e e n in th e Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 in g f r o m i n v a s i o n o f t h e p u l m o n a r y v e i n b y m etastatic c a r c in o m a , a n d th e s o u r c e w a s unknown i n t h e r e m a i n i n g t w o c a s e s . T h e d iscrep an cy b e tw e e n th e tw o se ts o f d a ta w ith r e s p e c t to e m b o l i c c a u s e s is p a r t i a l l y exp lain ed b y th e in c r e a s e d in c id e n c e o f su b a cu te b a c te r ia l e n d o c a r d i t i s in th e o ld er s tu d y . K u b i k a n d A d a m s (1 6 ) a ls o n o ted th a t in e v e r y c a s e o f t h r o m b o t i c o cclu sio n th e re w a s e x t e n s i v e a c c o m p a ­ n y in g b a s ila r a r te r y a t h e r o s c l e r o s i s a n d th at a t h e r o m a - r e l a t e d o c c l u s i v e t h r o m b u s w a s less f r e q u e n t in t h e d is ta l b a s i l a r a r ­ tery, a n o b s e r v a t i o n in a c c o r d a n c e w i t h th e d a t a o f C a s t a i g n e e t a l. (7 ). A cco rd in g to th e d a ta c ite d a b o v e (7, 1 6 ) a n d o t h e r r e s u l t s ( 8) , t h e c h i e f c a u s e of p r o x im a l b a s ila r a r t e r y o c c l u s i o n is in situ t h r o m b o s i s . I n d e e d , t h e s e s t u d i e s id en tified in s itu t h r o m b o s i s a s th e m a ­ jor c a u s e o f b a s i l a r a r t e r y o c c l u s i o n ; h ow ever, th e tru e fre q u e n c y o f e m b o lic o cclu sio n s m a y b e u n d e r e s t i m a t e d b e ­ cause th ese a re p a th o lo g ic a l d a ta a n d som e em b o li m a y s p o n ta n e o u s ly ly se o r fragm en t a n d p a s s d ista lly . T h e tru e o v erall f r e q u e n c y o f e m b o l i c o c c l u s i o n s is p r o b a b l y b e t t e r a s s e s s e d b y a n g i o ­ g ra p h ic s t u d i e s ; h o w e v e r , it is d i f f i c u l t to d r a w f i r m c o n c l u s i o n s f r o m t h e p u b ­ lish ed d a ta . T h i s c o n t r a s t s s o m e w h a t w ith o c c lu s io n o f th e m a j o r b r a n c h e s o f th e in te rn a l c a r o t i d a r t e r y , f o r w h i c h e m b o lis m is c o n s i d e r e d t h e m o s t f r e ­ q u e n t c a u s e ( 12, 1 8 ) . O c c l u s i o n o f t h e p o ste rio r c e r e b r a l a r te r ie s is, h o w e v e r , alm o st a lw a y s e m b o lic , a c c o r d i n g to C a s ta ig n e e t al. (7 ), a n d o c c l u s i o n o f th e d istal b a s ila r a r t e r y ( a b o v e t h e s u p e r i o r cereb ellar a r te r y o r ig in ), p r o d u c i n g th e to p o f th e b a s i l a r " s y n d r o m e , is m o s t o f t e n e m b o l i c ( 5) . 671 672 Phatouros et al re tro p e rito n e a l h e m a to m a , p o ssib ly re ­ la te d to a p re v io u s , re la tiv e ly h ig h in ­ g u in al p u n ctu re , sh o u ld b e co n sid e re d a s a lu ta r y w a r n in g . In a n y c a s e o f d ia g ­ n o s tic a n g io g r a p h y th a t m a y le a d to su b seq u en t th ro m b o ly tic th erap y , p a r­ ticu la r c a re s h o u ld b e ta k e n to e n s u re t h a t th e a r t e r i a l p u n c t u r e is b e l o w th e in g u in al lig a m e n t. 6 . C aro C G , Fitz-Gerald JM , Schroter RC: Arterial wall shear and distribution of early atheroma in man. N ature 2 2 9 :1 1 5 9 -1 1 6 1 , 1969. 7. C astaigne P, Lherm itte F, G autier JC, Escourolle R, D erouesne C, Der A gopian P, Popa C: Arte­ rial occlusions in the vertebro-basilar system: A study of 44 patients with post-mortem data. Brain 9 6 :1 3 3 -1 5 4 , 1973. 8 . C ravioto H, Rey-Bellet J, Prose PH, Feigin I: O cclusion of the basilar artery: A clinical and pathologic study of 14 autopsied cases. Neurol­ ogy 8 :1 4 5 -1 5 2 , 1958. SUM M ARY T h e v e rte b ro b a sila r ju n ctio n a n d p r o x ­ im a l b a s ila r a rte ry a re sites o f p re d ile c tio n fo r a th e ro s c le ro tic n a rr o w in g . In c a s e s o f b asilar a rte ry o cclu sio n re su ltin g fro m s u ­ p e rim p o se d th ro m b u s, a tte m p te d re ca n a ­ lizatio n w ith th ro m b o ly tic th e ra p y m a y b e u n s u c c e s s f u l (r e s u ltin g in a p o o r p r o g ­ n o sis) u n le ss p rim a ry tre a tm e n t o f th e stric­ t u r e is u n d e r t a k e n . If a n g i o p l a s t y fa ils, t h e n sten t p la c e m e n t re m a in s o n e o f th e fe w re­ m a in in g th e ra p e u tic o p tio n s. T h is clin ical s c e n a r i o is m o s t f r e q u e n t l y e n c o u n t e r e d in e ld e rly p a tie n ts, fo r w h o m e n d o v a s c u la r in ­ te rv e n tio n s a re m o r e lik ely to b e h in d e r e d b y v e s s e l to rtu o s ity . A flexib le a n d c o n f o r m ­ a b l e s t e n t is d e s i r a b l e if s u c c e s s f u l e n d o v a s ­ c u l a r d e l i v e r y is to b e r o u t i n e l y a c h i e v e d . T h e a u th o r s r e p o r t, fo r th e first tim e , th e feasib ility o f e n d o v a s c u la r p la c e m e n t o f a c o ro n a ry G ia n tu rc o -R o u b in -2 ste n t in to th e b asilar a rte ry for th e tre a tm e n t o f a n a c u te b asilar th ro m b o tic o cclu sio n related to u n ­ d e rly in g a th e ro scle ro tic sten o sis. 9. C ross DT, M oran CJ, A kins PT, Angtuaco EE, Diringer MN: Relationship of clot location and ou tcom e after basilar artery thrombolysis. Am J N eu ro rad io l 18:1221-1228, 1997. 10. Feldm an RL, Rubin JJ, Kuykendall RC: Use of a coronary Palm az-Schatz stent in the percutane­ ous treatm ent of vertebral artery stenoses. C ath et C ard iovasc D iag n 38:312-315, 1996. 11. Fields W S, Ratinov G, W iebel J, Campos RJ: S u rv iv a l fo llo w in g b a sila r artery occlusion. A rch N e u ro l 1 5 :4 6 3 - 4 7 1 , 1966. 12. Fisher C M , G ore 1, O k ab e N, W hite PD: Athero­ sclerosis of the carotid and vertebral arteries: Extracranial and intracranial. J Neuropathol Exp N eurol 24 :4 5 5 -4 7 6 , 1965. 13. Glagov S, Zarins C, Giddens DP, Ku DN: Hemo­ dynamics and atherosclerosis: Insights and per­ spectives gained from studies of human arteries. Arch Pathol Lab M ed 112:1018-1031, 1988. 14. H acke W, Z eu m er H, Ferbert A, Bruckmann H, del Zoppo GJ: Intra-arterial thrombolytic therapv improves outcome in patients with acute vertebro­ basilar occlusive disease. Stroke 19:1216-1222,1988. 15. Higashida RT, Sm ith W, Gress D, Urwin Rf Dowd CF, Balousek PA, Halbach VV: Intravas­ cular stent and endovascular coil placement for a ruptured fusiform aneurysm of the basilar artery: C ase report and review of the literature. J N eu rosu rg 8 7 :9 4 4 -9 4 9 , 1997. 16. R ubik CS, A d am s RD: Occlusion of the basilar artery: A clinical and pathological study. Brain Received, A ugust 24, 1998. Accepted, O ctober 28, 1998. Reprint requests: Constantine C. Phatouros, M.B.B.S., F.R.A.C.R., N eurovascular M edical Group, U CSF Medical Center, 505 Parnassus Ave., Room L-352, San Francisco, CA 94143-0628. R EFER EN C ES 1. Ahuja A, Guterman LR, Hopkins LN: Angioplasty for basilar artery ath e ro scle ro sis: C a se report. J N e u ro s u r g 7 7 :9 4 1 - 9 4 4 , 1992. m tk 17. Lherm itte J, Trelles JO: L'arterio sclerose du tronc basilaire et ses consequences anatomocliniques Ja h r b u e c h e r Psych Neurol 51:91-107, 69 :7 3 -1 2 1 , 1946. 1934. 18. Lhermitte F, Gautier JC, Derouesne C: Nature ot occlusions of the middle cerebral artery. Neurol­ ogy 20:82-88, 1970. 19. Meyer JS, Sheehan S, Bauer RB: .An arteriography study of cerebrovascular disease in man: I—Ste­ nosis and occlusion of the vertebro-basilar arterial system. Arch Neurol 2:27-45, I960. 20. N akatsuka H, Ueda T, Ohta S, Sakaki S: Suc­ cessful p ercutan eous transluminal angiopla^ 2. Archer CR, Horenstein S: Basilar artery occlusion: for basilar artery stenosis: Technical case report C linical and rad iolog ical co rrelatio n . S tr o k e 8 :3 8 3 - 3 9 0 , 1977. N eu rosu rgery 3 9 :16 1-1 64 , 1996. 21. Piotin M, Brunet E, Spelle L, R u fe n a c h t DA, 3. Biem ond A: T hrom bosis of the basilar arterv J Pico F, Benoist L, Rancurel G, Chiras J: Coro­ nary stents in the treatment of symptomatic ✓ * and the vascularization of the brain stem. Brain 7 4 :30 0-3 17, 1951. vertebral artery stenoses. Proc Symp Neurora 1la c k e W: Throm bolytic therapy of acute basilar diol 11 [Suppl 1R244S, 1998 (abstr). 22. R avensbergen J, Ravensbergen JW, Krijgor J^ artery occlusion: Variables affecting recanaliza­ Hillen B, Hoogstraten HW: Localizing role of N tion and outcom e. S tro k e 27:875-881, 1996. m odynamics in atherosclerosis in several humar 5. Caplan LR: "T o p of the basilar" syndrom e. N eurology 30:72-79, 1980. vertebrobasilar junction geometries. Arteriosc* 4. Brandt T, von R u m m er R, M uller-K uppers M, Neurosurgery , Vol. 44, No. 3, March 1999 T h ro m b Vase Biol 18:708-716, 1998. Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 p o s t m o r t e m s p e c i m e n i n Fig. 5 ) . T h e s e relativ ely w id e a p e rtu re s m a y b e d is a d ­ v a n t a g e o u s if th e s t e n t is u s e d a s a s c a f ­ fo ld to p r e v e n t h e rn ia tio n o f e le c tro ly tically d e ta c h a b le co ils in to th e p a re n t a r te r ia l l u m e n in th e t r e a t m e n t o f fu s i­ fo rm a n e u r y s m s . In th e b a s ila r a rte ry , h o w e v e r, w id e a p e rtu re s (a n d relativ ely th in stru ts) m a y b e th e o re tic a lly a d v a n ­ ta g e o u s in p re v e n tin g th e c o v e rin g a n d o cclu sio n , b y ste n t m e ta l-w o rk , o f th e o stia o f sm a ll p e rfo ra tin g v e sse ls o f th e b ra in ste m . In o u r ca se , p a th o lo g ica l e x ­ a m in a tio n d id n o t s h o w e v id e n c e o f b ra in s te m in fa rctio n re la te d to p e rfo ra ­ to r v e sse l o rig in o c c lu s io n b y th e sten t. T h e h isto lo g ica l a p p e a ra n c e o f th e rig h t o l i v a r y le s io n s u g g e s t e d t h a t it p r e d a t e d th e p ro c e d u re , a n d th e sm a ll p e te ch ia l p o n tin e h e m o r r h a g e sites w e r e c o n s id ­ e re d to b e to o fo cal to re p re s e n t p e rfo ­ ra to r o rig in o c c lu s io n s b y th e sten t. T h e w id e ste n t a p e rtu re s m a y h a v e also h e lp e d to m a in ta in th e p a te n c y o f th e rig h t v e rte b ra l a rte ry , b e c a u s e th e p r o x ­ im a l e n d o f th e ste n t e x te n d e d 3 m m in to th e left v e r te b r a l a r te r y a n d th e r e ­ fo re a t le a st p a rtia lly c o v e re d th e d istal rig h t v e rte b ra l a rte ry o stiu m . W e ch o se to u s e a 4 - m m - d i a m e t e r s te n t in a b a s ila r a r te r y w ith a m id -d ia m e te r o f 3 .6 m m . S o m e au th o rs p rev io u sly a d v o ca te d u n d e rd ila tin g (n o m o re th a n o n e -h a lf o f th e n o rm a l m id -d ia m e te r) b a sila r a rte ry ath ero sclero tic p la q u e w h e n p e rfo rm in g b a llo o n a n g io p la s ty , b e c a u s e o f th e in ­ su b sta n tia l m u scu la ris a n d a d v e n titia l la y e rs p o sse sse d b y th e b a sila r a rte ry w a ll a n d th e c o n s e q u e n t e le v a te d risk o f p e r f o r a t i o n ( 1, 2 0 ) . T h i s m a y b e o f e v e n g r e a t e r r e l e v a n c e in th e p r e s e n c e o f e c ­ cen tric p laq u e. U n d e rd ila tio n of p la q u e b y sim p le b allo o n a n g io p la sty m a y p ro ­ v i d e a s u f f ic ie n t i n c r e a s e in q u a n t i t a ti v e b lo o d flo w a n d m a y n o t re s u lt in a s ig ­ n ifica n t lik elih o o d of re ste n o sis o r t h r o m b o s i s (a t le a s t in th e s h o r t t e r m ) ; h o w e v e r, p re se rv a tio n o f sten t p a te n c y a t d i a m e t e r s o f ^2 m m s e e m s le s s s u r e . F u r th e r m o r e , th e risk o f v e sse l p e r f o r a ­ t i o n m a y n o t b e a s g r e a t w h e n a s t e n t is u se d , c o m p a re d w ith sim p le b allo o n a n ­ g io p la sty , w ith th e ste n t p o ssib ly p ro ­ v id in g a d d itio n a l w all s u p p o rt. F in a lly , th e fact th at, d e sp ite s u c c e s s ­ fu l in te r v e n tio n a n d a g o o d n e u r o lo g ic a l o u tc o m e , th e e v e n tu a l d e a th o f th e p a ­ tien t w a s a t le a st p a rtly c a u s e d b y a Basilar Stent 23. Sekhon LF1S, Morgan MK, Sorby W, Grinell V: Combined endovascular stent im plantation and endosaccular coil placement for the treatment of a wide-necked vertebral artery aneurysm: Techni­ cal case report. Neurosurgery 43:380-384, 1998. 24. Storey GS, Marks MP, Dake M, N orbash AM, Steinberg GK: Vertebral artery stenting follow ­ ing percutaneous translum inal angioplasty: Technical note. J N eu rosu rg 8 4 :8 8 3 -8 8 7 , 1996. 25. Sundt TM Jr, Smith HC, C am pbell JK , Vlietstra RE, Cucchiara RF, Stanson AW: Translum inal angioplasty for basilar artery stenosis. M ay o t h a t e v e r y d e t a i l is e x t r e m e l y i m p o r t a n t ; in th is c a s e , s o m e t h i n g a s b a s ic a s th e s ite o f th e fe m o ra l p u n c tu re m a y h a v e c o n ­ trib u te d to th e h e m o rrh a g ic s h o c k a n d u ltim ate ca rd ia c d em ise. W ith co n tin u ed d e v e lo p m e n t o f flexib le b a llo o n a n d s te n t s y s te m s , re p o rts s u c h a s th is w ill b e c o m e m o r e c o m m o n a n d w ill h e lp to r e d u c e th e p ro b le m s a sso cia te d w ith in tracran ial o c ­ clu sio n s a n d sten o ses. Clin Proc 55:673-680, 1980. 26. Tress BM, Mitchell RP, G erraty RP, D onnan GA, Fitt G, Thom son KR, Davis SM: Local in­ traarterial fibrinolysis in the vertebrobasilar system. Proc S y m p N e u r o r a d io l 11 [Suppl 1): 71-73, 1998. COM M ENTS T h is article d e scrib e s a m a n w ith b a si­ lar a rte ry th ro m b o e m b o lic o cclu sio n . T h is d is e a s e m a y b e v e r y d ifficu lt to tre a t b e ­ c a u s e o f th e a th e ro m a to u s p la q u e th at k e e p s th e v e sse l s te n o se d e v e n after th e clo t h a s u n d e rg o n e th ro m b o ly sis, le a d in g to r e t h r o m b o s i s . P l a c e m e n t o f th e s te n t in th is s itu a tio n w a s p ro b a b ly th e o n ly w a y th e a rte ry co u ld b e k e p t o p e n . T h is a p ­ p ro a c h m a y b e c o m e th e s ta n d a rd m e th o d b y w h i c h th is d i s e a s e is tr e a te d . A d v a n c e s in s te n t te c h n o lo g y a llo w th is a p p r o a c h u s in g s m a lle r a n d m o r e flexib le d e v ic e s . T h e a u th o rs a lso p ro v id e d th e p o s tm o r­ te m e x a m in a tio n resu lts; w ith o u t th a t a d ­ d itio n a l in fo rm a tio n , th e p a te n c y o f th e ste n t w o u ld a lw a y s b e q u estio n a b le . Stanley L. Barnwell P ortland, Oregon T h e a u th o rs d e scrib e th e p e rc u ta n e o u s e n d o v a scu la r p la ce m e n t of a G ian tu rco R o u b in -2 c o ro n a ry sten t for tre a tm e n t o f a n a cu te a th e ro th ro m b o tic o cclu sio n of th e b asilar a rte ry resu ltin g fro m h ig h g r a d e ste n o sis, w h ic h w a s id en tified after in tra-arterial th ro m b o ly sis a n d w h ich re ­ c u rre d im m e d ia te ly after p e rc u ta n e o u s tra n slu m in a l a n g io p la sty . T h e p atien t, u n ­ fo rtu n a te ly , s u ffe re d a fatal m y o c a r d ia l in fa rc tio n in th e p o s tp r o c e d u r a l p e rio d ; th e a u th o rs o b ta in e d p a th o lo g ica l a n d p o s tm o r te m e x a m in a tio n resu lts. T h e a u ­ th o rs a lso p re se n t a d e ta ile d re v ie w o f th e literatu re re g a rd in g v e rte b ro b a sila r a th ­ e ro scle ro tic o cclu siv e d ise a se , a s w ell a s a re v ie w o f m e th o d s o f rev ascu larizatio n . I a m cu rren tly a w a re of o n ly o n e o th er p u b lish e d re p o rt o f su ch sten t p la ce m e n t, b y th e s a m e a u th o r s (1). C e r ta in ly , fo r th e p a tie n t d e scrib e d h e re , th e in d ica tio n s for s te n tin g th is v e sse l w e r e a p p r o p r ia te . T h e a u th o rs c h o s e th e G ia n tu rc o -R o u b in -2 ste n t b e c a u s e o f th e d is ta n ce b e tw e e n sten t stru ts, w h ich th e o re tica lly w o u ld p re v e n t o cclu sio n o f b asilar a n d v e rte ­ b ral p e rfo ra tin g v essels. T h e a u th o rs d e ­ s c r ib e th e p r o c e d u r e in e x q u is ite d e ta il, in clu d in g a sa lu ta ry w a rn in g re g a rd in g h ig h in g u in al p u n c tu re s a sso cia te d w ith retro p erito n eal h e m a to m a s. It s h o u l d a ls o b e n o t e d th a t th e c o r o ­ n a ry A V E sten t (A rterial V a s c u la r E n g i­ n eerin g , S an ta R o sa , C A ) h a s e x ce p tio n a l tra ck in g ab ility a ro u n d tig h t c u rv e s , w h ic h m a y b e e n c o u n te r e d in th e in tra ­ c ra n ia l v a s c u la tu r e in e ld e r ly a th e r o s c le ­ ro tic p a tie n ts. A n o th e r g re a t a d v a n ta g e o f th e A V E s te n t is its i n c r e a s e d s ta b ility o n th e d e liv e ry b a llo o n , w h ic h m a y b e a d ­ v a n ta g e o u s d u rin g tre a tm e n t o f th ese p a r­ t i c u l a r l e s i o n s . T h i s e x c e l l e n t c a s e r e p o r t is a u se fu l a d d itio n to o u r c u rre n t b o d y o f k n o w le d g e a n d w ill b e a p p r e c ia te d b y m a n y n eu ro in terv en tio n alists. Donald W. Larsen Interventional N euroradiologist Los A ngeles, California 1. Higashida RT, Sm ith W, G ress D, Urvvin R, Dowd CF, Balousek PA, H albach VV: Intravascular stent and endovascular coil placem ent for a ruptured fusiform aneurysm of the basilar artery. J N eu rosu rg 8 7:944-949, 1997. A d ve rtisin g Inquiries regarding advertising in Neurosurgery should be directed to: Joyce Michael National Sales M anager Lippincott W illiam s & W ilkins 351 W est C am d en Street Baltim ore, M D 21201-2436 Tel: 410-528-4294 Fax: 410-528-4452 email: jm ichael@ w w ilkins.com Neurosurgery, Vol. 44, No. 3, March 1999 Downloaded from https://academic.oup.com/neurosurgery/article-abstract/44/3/667/2859269 by University of Western Sydney user on 08 January 2019 P h a to u ro s e t al. d e s c r i b e a n 8 3 - y e a r o ld m a l e p a t i e n t w h o p r e s e n t e d w i t h recu rren t tra n sie n t lo c k e d -in s y n d r o m e resu ltin g f r o m l o w e r b a s i l a r a r t e r y o c ­ clu sio n . D e s p i t e a t t e m p t s to r e o p e n t h e vessel w ith 9 7 5 ,0 0 0 u n its o f u r o k in a s e , th ere c o n t i n u e d to b e o n l y v e r y m e a g e r an tero g rad e b a sila r a r te r y flo w , d e m o n ­ stratin g s ig n if ic a n t s t e n o s i s a s th e c a u s e of th e o c c lu s io n . T h i s c a s e r e p o r t a l s o illu strates th a t in m a n y i n s t a n c e s a n g i o ­ p la sty a l o n e is i n e f f e c t i v e in m a i n t a i n i n g th e p a t e n c y o f t h e v e s s e l , b e c a u s e o f reco il o f th e p l a q u e . A s w e l e a r n f r o m our co lleag u es w h o p e r f o r m c a r d ia c a n d p erip h eral e n d o v a s c u l a r t h e r a p y , d e ­ p lo y m e n t o f a s te n t a f t e r a n g i o p l a s t y is o ften e s s e n tia l t o m a i n t a i n t h e p a t e n c y of th e tr e a te d v e s s e l . It is o f t e n d i f f i c u l t to d e t e r m i n e w h e t h e r a p o r t i o n o f t h e p la q u e is c a l c i f i c , a n d c e r t a i n l y a n g i o ­ p la s ty is f r a u g h t w i t h t h e p o t e n t i a l f o r vessel r u p tu r e a n d i m m e d i a t e n e u r o l o g ­ ical d e m i s e . H o w e v e r , w h e n w e i g h e d ag ain st th e n a tu r a l h i s t o r y o f u n t r e a t e d b asilar a r t e r y o c c l u s i o n , th is r i s k m a y b e w arran ted . T h e a u th o r s a ls o e m p h a s i z e Robert H. Rosenw asser Philadelphia, Pennsylvania 673