Kinks, Coils, and Carotids: A Review BY BINDU DESAI, M.B., B.S., AND JAMES F. TOOLE, M.D. Abstract: Kinks. Coils, and Carotids: A Review • Kinking and coiling of the internal carotid artery (ICA) sometimes may result in symp- tomatic cerebrovascular disease, but indisputable evidence linking the two conditions is lacking. However, there is enough evidence to warrant careful consideration of surgical correction in patients who have features of the carotid artery syndrome and kinking of the ICA as shown on angiography. Kinking or buckling of the artery is due to atherosclerosis and is to be dis- tinguished from coiling, which is ascribed to embryological causes. Definite recommendations regarding the advisability of surgery for infants who are dis- covered to have coils cannot be made, but coiling is generally asymptomatic. Adults with kinks in their carotid arteries who have recurrent transient ischemic attacks (TIAs) benefit most from surgical correction, particularly if symptoms are aggravated on head rotation, which may cause the kink to obstruct. Additional Key Words internal carotid artery cerebrovascular insufficiency head rotation anatomical variability surgical treatment D The association between kinking of the internal carotid artery (ICA) and cerebrovascular insufficiency was first noted in 1951. 1 Since then several reports have dealt with the clinical relationship between carotid elongation and kinking and cerebrovascular disease. Although conclusive evidence linking the two is still lacking, certain inferences can now be drawn. In this review we will critically examine previous reports of this anomaly and thereby derive useful clinical parameters for physicians who must decide whether surgical treatment is indicated in patients with angiographical evidence of a kinked carotid and symptoms of cerebrovascular insufficiency. As the in- cidence of this abnormality in the total population has been estimated to be as high as 16%, 2 the importance of its correct diagnosis and treatment cannot be overemphasized. History The anatomical variability of the ICA has been clearly recognized for decades. Its relationship to the tonsil was of special interest to otolaryngologists who at first thought the vessel might be the ascending pharyngeal. 3 Detailed reports 4 ' 5 later confirmed that the ICA when tortuous "becomes a directly lateral relation of the tonsil, [with] only the superior constrictor in- tervening." 4 (p 95) The hazard of fatal hemorrhage dur- ing tonsillectomy was recorded 5 and subsequently resulted in a timely warning graphically stated by Skillern: "Before operating, the surgeon should Stop, Look, and Listen. A thorough ocular and digital ex- ploration of the pharynx for arterial pulsations should never be omitted." 6 Recognition of the association From the Department of Neurology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27103 (reprint requests). Supported by USPHS, NINDS Grant #06655. between cerebrovascular disease and looping and kinking of the ICA is comparatively recent. 1 Pathology DEFINITION OF COILS AND KINKS Determining the precise nature of the carotid artery abnormality through arteriography is crucial in deciding whether surgical intervention is indicated. In this regard the definition of coils and kinks given by Weibel and Fields 7 is very helpful. (We applied it in our review of the case reports considered later.) Ac- cording to this definition, coiling is elongation and redundancy of the ICA resulting in an exaggerated S- shaped curvature or in a circular configuration. Kink- ing is described as angulation of one or more segments of the ICA associated with stenosis in the affected seg- ment. EMBRYOLOGY AND SYMPTOMATOLOGY Looping and kinking of the ICA has been observed in infants 8 and even in fetuses. 4 The cause of these loops is related to embryological development. 9 The vessel is formed from the third aortic arch and from the dorsal aorta; hence, in the embryo it is normally kinked. Straightening occurs when the fetal heart and large vessels recede in the thoracic cavity. If the em- bryological state persists, it produces different kinds of undulations, loops, and kinks. This anomaly generally does not become symp- tomatic until later in life. 2 There appears to be no relationship between the severity of the kinking and either rising blood pressure or increasing age. The role of degenerative changes in the vessel wall remains un- certain. If this factor were important, then kinks should be more severe in older individuals because degenerative changes increase with age; however, this is not generally the case. At best the cause for looping and kinking of the carotid artery may be ascribed Stroke, Vol. 6, November-December 1975 649 by guest on May 11, 2018 http://stroke.ahajournals.org/ Downloaded from
Transcript
Kinks, Coils, and Carotids: A ReviewBY BINDU DESAI, M.B., B.S., AND JAMES F. TOOLE, M.D.
Abstract:Kinks.Coils, andCarotids:A Review
• Kinking and coiling of the internal carotid artery (ICA) sometimes may result in symp-tomatic cerebrovascular disease, but indisputable evidence linking the two conditions is lacking.However, there is enough evidence to warrant careful consideration of surgical correction inpatients who have features of the carotid artery syndrome and kinking of the ICA as shown onangiography. Kinking or buckling of the artery is due to atherosclerosis and is to be dis-tinguished from coiling, which is ascribed to embryological causes.
Definite recommendations regarding the advisability of surgery for infants who are dis-covered to have coils cannot be made, but coiling is generally asymptomatic. Adults with kinksin their carotid arteries who have recurrent transient ischemic attacks (TIAs) benefit most fromsurgical correction, particularly if symptoms are aggravated on head rotation, which may causethe kink to obstruct.
Additional Key Wordsinternal carotid artery
cerebrovascular insufficiencyhead rotation
anatomical variabilitysurgical treatment
D The association between kinking of the internalcarotid artery (ICA) and cerebrovascular insufficiencywas first noted in 1951.1 Since then several reportshave dealt with the clinical relationship betweencarotid elongation and kinking and cerebrovasculardisease. Although conclusive evidence linking the twois still lacking, certain inferences can now be drawn. Inthis review we will critically examine previous reportsof this anomaly and thereby derive useful clinicalparameters for physicians who must decide whethersurgical treatment is indicated in patients withangiographical evidence of a kinked carotid andsymptoms of cerebrovascular insufficiency. As the in-cidence of this abnormality in the total population hasbeen estimated to be as high as 16%,2 the importanceof its correct diagnosis and treatment cannot beoveremphasized.
HistoryThe anatomical variability of the ICA has been clearlyrecognized for decades. Its relationship to the tonsilwas of special interest to otolaryngologists who at firstthought the vessel might be the ascending pharyngeal.3
Detailed reports4'5 later confirmed that the ICA whentortuous "becomes a directly lateral relation of thetonsil, [with] only the superior constrictor in-tervening."4 (p 95) The hazard of fatal hemorrhage dur-ing tonsillectomy was recorded5 and subsequentlyresulted in a timely warning graphically stated bySkillern: "Before operating, the surgeon should Stop,Look, and Listen. A thorough ocular and digital ex-ploration of the pharynx for arterial pulsations shouldnever be omitted."6 Recognition of the association
From the Department of Neurology, Bowman Gray School ofMedicine, Wake Forest University, Winston-Salem, NorthCarolina 27103 (reprint requests).
Supported by USPHS, NINDS Grant #06655.
between cerebrovascular disease and looping andkinking of the ICA is comparatively recent.1
PathologyDEFINITION OF COILS AND KINKS
Determining the precise nature of the carotid arteryabnormality through arteriography is crucial indeciding whether surgical intervention is indicated. Inthis regard the definition of coils and kinks given byWeibel and Fields7 is very helpful. (We applied it inour review of the case reports considered later.) Ac-cording to this definition, coiling is elongation andredundancy of the ICA resulting in an exaggerated S-shaped curvature or in a circular configuration. Kink-ing is described as angulation of one or more segmentsof the ICA associated with stenosis in the affected seg-ment.
EMBRYOLOGY AND SYMPTOMATOLOGY
Looping and kinking of the ICA has been observed ininfants8 and even in fetuses.4 The cause of these loopsis related to embryological development.9 The vessel isformed from the third aortic arch and from the dorsalaorta; hence, in the embryo it is normally kinked.Straightening occurs when the fetal heart and largevessels recede in the thoracic cavity. If the em-bryological state persists, it produces different kindsof undulations, loops, and kinks.
This anomaly generally does not become symp-tomatic until later in life.2 There appears to be norelationship between the severity of the kinking andeither rising blood pressure or increasing age. The roleof degenerative changes in the vessel wall remains un-certain. If this factor were important, then kinksshould be more severe in older individuals becausedegenerative changes increase with age; however, thisis not generally the case. At best the cause for loopingand kinking of the carotid artery may be ascribed
partly to embryological development and partly assecondary to atherosclerotic changes.
Carotid Artery SyndromeBy definition, in the carotid artery syndrome theoffending carotid artery is held responsible only forthe following features: (1) contralateral hemiparesis,which may be transient, or hemiplegia, with orwithout sensory deficit; (2) ipsilateral monocularvisual dysfunction; (3) ipsilateral frontal headache; (4)homonymous field defects; and (5) language defect(partial or complete) only when the dominanthemisphere is involved.
Symptoms such as syncope, confusion, roaring inthe ears, and memory loss when cited as being due toipsilateral carotid artery disease are considered onlywhen the total angiographical report permits aclinicopathological correlation.
Occurrence in Infants and ChildrenFew reports deal with the association betweeninfantile hemiplegia and kinking and coiling of thecarotid artery. Sarkari's series8 consisted of nine in-fants with cerebrovascular disease who exhibited uni-lateral or bilateral looping or kinking. Theorizing thatthe vascular anomaly may have been responsible forthe hemiplegia, they suggested surgical correction insuch patients. The severe neurological deficits in theseinfants, due to looping of the carotid artery, weredifficult to explain. A combination of events (suddenobstruction, neck rotation, and microemboli) couldhave been responsible for the cerebral ischemia;however, because no pathological studies of the vesselinvolved were performed, we do not have evidence for
emboli formation. We believe that kinking of thevessel could cause eddy currents and microemboli for-mation due to slowing of blood flow at the site. Theseemboli would not result in any change in the vesselwall itself but could cause cerebral ischemia.
Parrish and Byrne10 reported five cases ofhemiparesis and seizures in children who hadangiographical evidence of kinking of the ICA. Twoof these also had occluded middle cerebral arteries butwere surgically treated and clinical improvement wasnoted.
At this stage we recommend carotid angiographyin infantile hemiplegia but are unable to give definitecriteria for surgical correction of loops or kinks. Thismust await further study.
Occurrence in AdultsSeveral reports deal with this condition in adults (table1); we will consider them each in turn.
Gass' study11 included one patient with recurrentattacks of left hemiparesis and left hemisensorydeficit. The patient was treated surgically but threemonths later had an occluded ICA without anyresulting symptoms. Although Gass reported on somecases with sudden loss of consciousness, detailedangiographical evidence linking the symptom to thevascular anomaly is lacking. Therefore, we cannotcomment on these cases.
In the study by Derrick et al.,12 no specific cor-relation of symptomatology and arteriographical ab-normalities is found. The symptoms were ratherbroad-based and not strictly due to the carotid arterysyndrome. Interestingly, 19 of these patients ex-perienced symptoms associated with some extrememovement of the head.
TABLE 1
Summary of Adult Patient Data From Previous Studies
Study
Gass11
Derrick12
Quattlebaum13
Sanger14Rundles1"'Harrison16
Freeman17
Najafi18
No. ofpt..
658
138
58
46
4415
Correlationfactor*
VestNo
No
YesYesNo
NoYes
No. treatedsurgically
158
138
55
35
4415
Period offollow-up
3 months2-6 years (28)}
1-14 years (109)J
None13 months3 years
Not stated5 months-4 years
Results
Improved13—no recurrence of symptoms;
12—slight return of symptoms;1—unimproved; 2—died ofunrelated causes
39—excellent; 61—good;14—fair; 24—poor
All improved immediately3 improvedImprovement in 6 of 9 with
hemiplegia, 9 of 12 withstroke in evolution, 11 of 14TIAs
40 improved11 improved
•Individual cases correlated in terms of clinical symptoms and angiographical abnormality.fSudden contralateral hemiparesis or loss of consciousness in four cases; repeated leftsided transient attacks inone case; bruit over left mastoid in one case.^Number in parentheses indicates number of patients included in follow-up.
Quattlebaum et al.13 reported that patients with ahistory of transient ischemic attacks (TIAs) who wereoperated on did well after surgery (82%), whereasthose with symptoms of a more diffuse nature did not.
All of the patients studied by Sanger et al.14 hadthe classical carotid artery syndrome. Unfortunately,no follow-up on these cases is available.
The study by Rundles and Kimbell15 includedthree cases with symptoms more likely to bevertebrobasilar than cerebrovascular in origin. Thefollow-up period is too short for any conclusions to bedrawn.
Harrison and Davalos16 treated nine patients withhemiplegia and 12 with stroke in evolution. Becauseno specific correlation of angiographical abnor-malities and symptoms is available, these cases aredifficult to assess.
Freeman and Lippitt17 reported a 92% incidenceof relief in their patients, but no follow-up is available.
Najafi et al.18 followed their cases for a period offive months to four years. Three of the 15 cases cannotbe strictly included in the carotid artery syndrome.
DiscussionAs can be noted from table 1, a fairly large number ofcases with kinking or coiling of the carotid artery havebeen operated on and followed for various intervals.Symptomatic improvement following surgery is notedin nearly all the reports but no standardized criteria tojudge the improvement have been applied.
None of the authors claim to imply that kinksand coils of the carotid artery are invariably symp-tomatic.11"18 The evidence suggests that coilingwhether unilateral or bilateral rarely results in symp-toms unless there is also atherosclerotic occlusive dis-ease in the carotid, vertebral, or basilar arteries.7
When symptoms occur, they may be secondary to dis-ease of intracranial vessels not adequately visualizedby routine arteriography. Kinking of the ICA alonemay occasionally cause symptoms of cerebrovasculardisease, but several other factors such as variation inblood pressure, alterations in head and neck positions,and extracranial or intracranial occlusive diseasescontribute significantly to the production of cerebralsymptoms. Sometimes "development of symptomsdepends on the fortuitous positioning of the head insuch a way that the vessels are kinked ratherthan merely elongated."13 lp s76) Recurrent episodes ofcerebrovascular insufficiency are more common inpatients with kinks than in controls though this is justoutside the conventional 5% level of significance.2 In-disputable evidence for any connection between kink-ing of the ICA and cerebrovascular symptoms doesnot exist. However, the evidence is suggestive enoughto prompt careful consideration of surgical excision inpatients with recurrent cerebrovascular episodes whohave a kink and in whom no other adequate cause canbe found in the cerebrovascular or cardiovascular
systems. Surgery should be especially considered inthose cases in which rotation of the neck producessymptoms.2
According to Culligan,19 buckling of the greatvessels at the base of the neck does not require surgicalcorrection. The circulatory dynamics in the kinkedcarotid artery have been studied experimentally,20 andan inverse relationship between the severity of thekink and the blood pressure and blood flow distal tothe kink has been noted; however, not everyone agreesthat cerebrovascular insufficiency is directly related tothe degree of angulation of the kinked segment.7
It is gratifying that patients with TIAs and a con-tralateral looped or kinked carotid artery generallyimproved or had no further symptoms following sur-gery.13' " This is probably the strongest indication forsurgical correction of a kinked carotid. Since the sur-gery on these patients involved a generous resection ofthe common carotid artery,21 it also required remov-ing the most common site of atherosclerotic plaqueformation. Therefore, straightening of the ICA maynot be the only reason for the improvement.
Several patients were treated surgically for symp-toms (vertigo, blackout, progressive mental deteriora-tion) not strictly attributable to carotid artery dis-ease.13 Loss of balance22 and tinnitus15 are moreproperly considered as resulting from vertebrobasilarinsufficiency. Patients with completed strokes16 orspastic hemiparesis23 should not be considered suitablesurgical candidates.
Our own experience includes seven patients withTIAs and angiographical evidence of tortuosity withor without kinking of the ICA. Five had symptoms ofvertebrobasilar insufficiency. The sixth had transientrightsided weakness and marked tortuosity of the leftICA. She was not treated surgically. Two years latershe complained of generalized weakness but had noneurological deficit.
The last patient was a 77-year-old man withrecurrent transient bouts of leftsided weakness.Angiography revealed a loop in the midcervical por-tion of the ICA with a 2-mm posterior wall ulcer nearthe carotid bifurcation (fig. 1). Head rotation did notresult in occlusion of the vessel. The patient was ini-tially anticoagulated with coumadin, but this was dis-continued when he had another episode of cerebro-vascular insufficiency, this time resulting in a mild lefthemiparesis. Surgical correction of the carotid wasthen done, involving right carotid endarterectomy,with the redundant ICA resected and then reim-planted into the common carotid via end-to-end anas-tomosis. Blood flow in the ICA, which was 90 to 110ml before surgery, increased to 700 ml following theoperation. Pathological examination revealed athero-sclerotic intima and media with evidence of fresh hem-orrhage in the atherosclerotic plaque. This case is ofinterest for several reasons. Though head rotation didnot result in occlusion of the blood vessel, blood flow
Loop in the midcervical portion of the ICA with a 2-mm posteriorwall ulcer near the carotid bifurcation.
increased markedly following surgery. Also the freshhemorrhage seen on pathological examination couldhave resulted from anticoagulation.
Perhaps the best explanation for exploring thepossible relationship between kinking of the ICA andcerebrovascular disease was given by Metz et al: "It isalways difficult to be certain of the relevance of anyfactor to the production of cerebrovascular symptoms.Cessation of symptoms after removal of a factor doesnot establish the existence of a causal relation betweenthe two. It is well recognized, for example, that tran-sient ischemic episodes may cease spontaneously;hence, the disappearance or non-recurrence of symp-toms following the excision of a kink in the internalcarotid artery must be interpreted with caution.Nevertheless, the present unsatisfactory state oftherapy for cerebrovascular disease demands thateach potential method of treatment be thoroughlyassessed."2 (p m )
ConclusionsInfants with hemiplegia may show kinking andlooping of the carotid arteries on angiography.
Definite criteria for surgical corrections do not exist asyet and await further study.
Kinking and looping of the carotid artery mayresult partly from embryological development andpartly as secondary to atherosclerotic changes.
Symptoms of cerebrovascular insufficiency inadults, investigated by angiography, may show kink-ing and coiling of the ICA. Surgery is probably in-dicated when the symptoms consist of recurrent TIAsand there is angiographical evidence of kinking in theresponsible carotid artery. Production of symptomson head rotation further strengthens the case for sur-gery.
References1. Riser M, Geraud J, Ducoudray J, et al: Dolichocarotide
interne avec syndrome vertigineux. Rev Neurol 85x145-147,1951
2. Metz H, Murray-Leslie RM, Bannister RG, et al: Kinking of theinternal carotid artery in relation to cerebrovascular disease.Lancet 1:424-426 (Feb 25) 1961
3. Connolly JH: Large pulsating vessel in the right portion of theposterior pharyngeal wall, partly concealed behind the righttonsil, in a. boy, aged 5. Proc R Soc Med 7l25-26 (Nov 7)1913
4. Cairney J: Tortuosity of the cervical segment of the internalcarotid artery. J Anat 39:87-96, 1924
5. Fisher AGT: Sigmoid tortuosity of the internal carotid arteryand its relation to tonsil and pharynx. Lancet 2:128-130,1915
6. Skillern PG, cited by Jackson JL: Tortuosity of the internalcarotid artery and its relation to tonsillectomy. Canad MedAssoc J 29:477, 1933
7. Weibel J, Fields WS: Tortuosity, coiling and kinking of the in-ternal carotid artery. II. Relationship of morphological varia-tion to cerebrovascular insufficiency. Neurology 15:462-468, 1965
16. Harrison JH, Davalos PH: Cerebral ischaemia: Surgicalprocedure in cases due to tortuosity and buckling of the cer-vical vessels. Arch Surg 84:85-94, 1962
19. Culligan JA: Buckling and kinking of the carotid vessels.Minn Med 43:678-683, 1960
20. Derrick JR, Estess M, Williams D: Circulatory dynamics inkinking of the carotid artery. Surgery 58:381-383, 1965
21. Quattlebaum JK, Upson ET, Neville RL: Stroke associated
with elongation and kinking of the internal carotid artery:Report of three cases treated by segmental resection of thecarotid artery. Ann Surg 150:824-832, 1959
22. Barnes WT, Smedley WP: Carotid insufficiency due toelongation and kinking of the internal carotid artery. PaMed 68:41-43, 1965
23. Bauer R, Sheehan S, Meyer JS: Arteriographic study ofcerebrovascular disease. II. Cerebral symptoms due to kink-ing, tortuosity and compression of the carotid and vertebralarteries in the neck. Arch Neurol 4:119-131, 1961
is published by the American Heart Association, 7272 Greenville Avenue, Dallas, TX 75231Stroke doi: 10.1161/01.STR.6.6.649
1975;6:649-653Stroke.
http://stroke.ahajournals.org/content/6/6/649World Wide Web at:
The online version of this article, along with updated information and services, is located on the
http://stroke.ahajournals.org//subscriptions/
is online at: Stroke Information about subscribing to Subscriptions:
http://www.lww.com/reprints Information about reprints can be found online at: Reprints:
document. Permissions and Rights Question and Answer available in the
Permissions in the middle column of the Web page under Services. Further information about this process isOnce the online version of the published article for which permission is being requested is located, click Request
can be obtained via RightsLink, a service of the Copyright Clearance Center, not the Editorial Office.Stroke Requests for permissions to reproduce figures, tables, or portions of articles originally published inPermissions:
