Article Text

Download PDFPDF
143 Carotid Intraplaque Neovascularization is Increased in Patients with Prior Ipsilateral Neck Irradiation - A Contrast Enhanced Ultrasound Study
  1. Roxy Senior1,
  2. Dorothy M Gujral2,
  3. Navtej S Chahal2,
  4. Kevin J Harrington2,
  5. Christopher M Nutting2,
  6. Benoy Shah1
  1. 1Royal Brompton Hospital* And Northwick Park Hospital
  2. 2Royal Brompton Hospital


Background Irradiation of the carotid artery during radiotherapy (RT) for head/neck cancer (HNC) increases intima-media thickness, plaque formation and risk of stroke. However, the effects of RT on plaque composition are unknown. Intraplaque neovascularization (IPN) is a precursor to intraplaque haemorrhage and thus considered to be a marker of plaque instability. Contrast-enhanced ultrasound (CEUS) is a novel method of indirectlyassessing plaque vulnerability by detection of IPN.

Methods B-mode and CEUS carotid ultrasonography were performed in survivors of HNC who had received RT >2 yrs previously and had received >50Gy dose to the ipsilateral neck. Patients with bilateral RT were excluded. Baseline patient demographics were noted. Long and short axis views of the ipsilateral (RT side) and contralateral (non-RT side) carotid arteries were recorded, first in B-mode and then CEUS, using a continuous IV infusion of Sonovue contrast. IPN was graded semi-quantitatively as absent (Grade 0), limited to the adventitia/plaque base (Grade 1) or extensive and/or extending into the plaque body (Grade 2) by a doctor blinded to the laterality of RT.

Results A total of 49 patients were enrolled. Mean age was 57 ± 8yrs, 69% were male and mean BMI was 26 ± 4 kg/m2. The mean interval from RT to carotid imaging was 5.3 ± 2.6 years. Plaques were found in 38 (78%) patients, of whom 36 had plaques on the RT vs. 17 on the non-RT side (73 vs. 35%, p < 0.001). IPN was seen in 29/36 patients with RT-side vs. 7/17 patients with non-RT side plaques (81 vs. 41%, p = 0.004). Grade 2 IPN was seen in 14/36 patients with RT-side vs. 2/17 patients with non-RT side plaques (39 vs. 12%, p = 0.04).

Conclusions This is the first study to assess carotid plaque composition in HNC patients treated with RT. IPN, detected non-invasively by CEUS, is more prevalent in plaques from irradiated arteries. These results indicate that the increased risk of stroke in such patients may be due to RT-mediated proliferation of IPN.

  • Carotid Artery
  • Contrast Ultrasound
  • Radiotherapy

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.