Nuclear medicine

The study find that PET/CT images are offering evidence of a link between vascular patterns at the time of diagnosis for giant cell arteritis and a patient’s risk of an ischemic event; therefore Spanish researchers explain in a study publish online on 12 May in the European Journal of Nuclear Medicine and Molecular Imaging. Because “Bearing in mind these results and our findings; They  consider that the vertebral arteries are carefully study in patients with suspected GCA; not only to support the diagnosis but also to assess the risk of development of ischemic events.”

The vertebral arteries

The PET/CT results; the researchers discover that 23 patients (77%) had at least one vascular region with ischemia. The same number of patients exhibited large-vessel vasculitis; which included aortic and vertebral artery involvement. In addition; 18 patients (60%) are show to have isolate involvement of the vertebral arteries. The remaining vascular territories the carotid arteries; subclavian arteries, brachiocephalic trunk, axillary arteries, and aorta  were less frequently involve.

Giant cell arteritis is an inflammatory disease that causes the large blood vessels to narrow and restrict blood flow. The affliction is typically see in the temporal arteries and the aorta in adults older than 50. Currently; there is little information on how the disease develops; although there are indications that it may be link to genetics.

The large blood vessels

The challenge for clinicians is that there are “no specific clinical symptoms that lead to the diagnosis of GCA, but headache and ischemic symptoms such as jaw claudication and transient visual loss or permanent visual loss may raise suspicion [of the disease];” the authors noted.

Scanning temporal arteries with Doppler ultrasound has been shown to have good positive predictive value in patients with suspected GCA; and FDG-PET/CT can achieve good diagnostic accuracy for this clinical application; with previous research citing sensitivity of 83% and specificity of 89%. However; few studies are available that assess FDG-PET/CT’s efficacy in detecting clinical signs and symptoms of the disease early in its development.

Scanning temporal arteries

“The study of this field is critical; since it may have therapeutic and prognostic implications in daily clinical practice;” Mestre-Torres and colleagues wrote. “The objective of the present study was to evaluate the existence of different patterns of vascular involvement on PET/CT in patients with GCA according to the presence or absence of ischemic manifestations at disease onset.

“Images were acquired during the first 10 days of steroid therapy on a 64-slice CT and dedicated PET scanner (Biograph  from the skull to both upper femurs following intravenous injection of 3.7 MBq/kg of FDG. The results were interpreted by two nuclear medicine specialists who were blinded to all clinical information related to evidence of ocular and/or ischemic symptoms.