State of the art head and neck imaging for the endovascular specialist

Postirradiated carotid blowout syndrome in patients with nasopharyngeal carcinoma: a case-control study

BACKGROUND

Carotid blowout syndrome is one of the most devastating complications of nasopharyngeal carcinoma (NPC) therapy.

METHODS

A retrospective review was conducted from January 2004 to April 2013. Thirty-one patients with carotid blowout syndrome were enrolled and a case control study was conducted to analyze the risk factors.

RESULTS

When a comparison was made between the carotid blowout syndrome and matched non-bleeding group, there was a significantly higher local recurrence rate and prevalence of skull base osteoradionecrosis (ORN) in the carotid blowout syndrome group compared to those of the control group (both p < .001). The hazard ratio of carotid blowout syndrome was 3.599 between patients with or without reirradiation (95% confidence interval, 1.465-8.839; p = .005, adjusted for nasopharyngectomy and chemotherapy) using a Cox proportional hazard model.

CONCLUSION

Reirradiation and skull base ORN are strong predisposing factors for carotid blowout syndrome, and therefore they should be mentioned in the informed consent form before treatment.

Diagnostic yield of delayed phase imaging in CT angiography of the head and neck: a retrospective study

PURPOSE

To evaluate how often delayed images, obtained during neurovascular CTA, provide unique information relative to early phase imaging alone.

MATERIALS AND METHODS

Informed consent was waived by the institutional review body for this study. Neurovascular CTAs from January through June 2009 were searched to identify those with delayed phase imaging. Reports were reviewed to identify cases where delayed images provided potentially unique information. The studies with potentially unique information were re-interpreted to determine if the information was indeed unique.

RESULTS

645 CTAs with delayed phase imaging were identified. There were 324 men and 310 women (median age 67 years; range 20-96 years). 59 studies (59/645: 9.1%) had findings on the delayed images. There were 13 cases with hemorrhage, with 4 showing progression on delayed views. Of the remaining 46 cases, 28 had occlusion of a vessel that did not reconstitute on the delayed images, 6 had occlusion of a vessel that did reconstitute on the delayed images, 7 had a string sign which was unchanged on the delayed views and 5 had no abnormal findings. Thus in 10 cases the findings were unique to the delayed images (10/645: 1.55%). Four showed active bleeding, three showed proximal occlusion with distal internal carotid filling from ophthalmic collaterals, two showed pial vessels filling distal to proximal MCA occlusion, and one showed retrograde vertebral artery filling due to subclavian steal. 95% confidence limits of the expected incidence of unique information from the delayed phase images are 0.6%-2.5%.

CONCLUSION

Obtaining delayed phase imaging for neurovascular CTA should be an active decision and not the default protocol. This avoids imaging with little, if any value. If delayed images had not been obtained in our cohort, no detriment in patient management would have occurred.

Different imaging techniques in the head and neck: Assets and drawbacks

In this review, the gold standard imaging techniques for the head and neck and the latest upcoming techniques are presented, by comparing computed tomography (CT), magnetic resonance imaging and positron emission tomography-CT, as well as ultrasound, depending on the examined area. The advantages and disadvantages of each examination protocol are presented. This article illustrates the connection between the imaging technique and the examined area. Therefore, the head and neck area is divided into different sections such as bony structures, nervous system, mucous membranes and squamous epithelium, glandular tissue, and lymphatic tissue and vessels. Finally, the latest techniques in the field of head and neck imaging such as multidetector CT, dual-energy CT, flash CT, magnetic resonance angiography, spectroscopy, and diffusion tensor tractography using 3 tesla magnetic resonance are discussed.