title: Carotid tortuosity in patients with prior cervical radiation: increased technical challenge during carotid stenting.
abstract: BACKGROUND
  Anatomic distortion associated with radiation-induced tissue changes may pose challenges for patients with prior cervical irradiation undergoing carotid stenting. We sought to evaluate the effect of these changes on carotid intervention.
  
  
  METHODS
  Carotid angioplasty and stenting (CAS) for high-grade stenosis was performed in 203 patients. In all, 12 consecutive patients with prior ipsilateral cervical irradiation were age-/sex-matched to 24 controls. Degree of internal carotid (IC) tortuosity was assessed by 4 methods: (a) deviation of IC from common carotid (CCA) axis, (b) number of intersections between this axis and the course of the IC, (c) total degrees of angulation along the course of the extracranial IC, and (d) the IC length to straight-line distance ratio.
  
  
  RESULTS
  Carotid angioplasty and stenting was successful in all patients. Mean age was 72.8 ± 10 years; 58.4% were male. Twenty-nine percent were symptomatic (14.4% transient ischemic attack [TIA], 8.5% cardiovascular accident [CVA], and 6.5% amaurosis). Comorbidities were similar between the entire cohort and the subgroups of irradiated/control patients. The IC revealed a higher degree of deviation from the axis of the CCA in the previously irradiated patients compared to those without radiation (29.2° ± 4.5° vs 13.0° ± 2.0°, P = .001) and was more likely to intersect this axis in those with a history of cervical irradiation (83.3% vs 14.3%, P < .05). Irradiated patients also exhibited a significantly greater degree of tortuosity versus nonirradiated patients when assessed by total angulation along the course of the carotid (171.8° ± 26.0° vs 74.2° ± 20.2°, P = .014) and by the IC length:distance ratio (1.14 ± 0.05 vs 1.04 ± 0.03, P = .020). Despite increased IC tortuosity in patients with prior irradiation, all procedures were successfully completed and there did not appear to be a predilection for a specific filter type.
  
  
  CONCLUSIONS
  A history of cervical irradiation is associated with increased tortuosity of the IC, leading to potential challenges for filter and stent deployment. However, this increased procedural complexity did not affect technical success rate or device selection in this series.
authors.affiliation: Division of Vascular Surgery, UCLA Medical Center, Geffen School of Medicine, Los Angeles, CA, USA. bderubertis@mednet.ucla.edu
authors.forename: Brian G
authors.initials: BG
authors.lastname: Derubertis
authors.forename: Robert L
authors.initials: RL
authors.lastname: Hynecek
authors.forename: K Craig
authors.initials: KC
authors.lastname: Kent
authors.forename: Peter L
authors.initials: PL
authors.lastname: Faries
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000800:Angioplasty, Balloon / Q000009:adverse effects* / Q000295:instrumentation*; D002343:Carotid Artery, Internal / Q000473:pathology / Q000528:radiation effects*; D016893:Carotid Stenosis / Q000150:complications / Q000473:pathology / Q000628:therapy*; D016022:Case-Control Studies; D002561:Cerebrovascular Disorders / Q000209:etiology; D016009:Chi-Square Distribution; D057505:Embolic Protection Devices; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries / Q000150:complications* / Q000473:pathology; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D015607:Stents; D016896:Treatment Outcome