Karahaliou et al reported an algorithm for the diagnosis of giant cell arteritis using color Doppler ultrasonography. It is a modification of one proposed by Hellman and Hunder.
Patient selection: suspicion for giant cell arteritis (GCA)
Examination: bilateral cranial color Doppler ultrasonography
Parameters:
(1) halo sign seen on ultrasonography
(2) biopsy finding
(3) continued clinical suspicion of GCA
|
Halo Sign |
Biopsy Finding |
Continued Suspicion |
Action |
|
bilateral |
NA |
NA |
GCA proven |
|
unilateral |
positive |
NA |
GCA proven |
|
unilateral |
negative |
high |
see below |
|
unilateral |
negative |
low |
stop workup |
|
none |
positive |
NA |
GCA proven |
|
none |
negative |
high |
see below |
|
none |
negative |
low |
stop workup |
If GCA is still suspected but the halo sign and biopsy are negative then consider:
(1) rebiopsy of a temporal or occipital artery (using US findings to identify a high risk area)
(2) consider other imaging study such as high-resolution MRI
A patient whose workup is stopped may be monitored to see if further findings supporting or excluding GCA occur.
Purpose: To evaluate a patient for giant cell arteritis (GCA) using color Doppler ultrasonography.
Specialty: Immunology/Rheumatology
Objective: risk factors, imaging studies, prevention
ICD-10: M31.5, M3.6,
