TABUL is a multi-centre blinded study to compare Temporal Artery Biopsy and Ultrasound in diagnosis of Giant Cell Arteritis.
Giant Cell Arteritis (GCA) is a disease which affects the blood vessels to the scalp and can also affect other blood vessels. It causes narrowing and blockage of some of these blood vessels and can cause blindness in about one third of patients. Because of the risk of blindness, it is important that a prompt and accurate diagnosis of GCA can be made in order to start treatment with steroid tablets or injections.
It is important to find better ways of diagnosing GCA to ensure that more patients are treated appropriately. Some patients may decide that they do not want to have a biopsy. Another test that may help in diagnosing GCA is examination of ultrasound scans of the arteries in the side of the head and under the arms. Ultrasound does not involve surgery; it is a simple test which can be performed in a radiology department. Gel is applied to both sides of the head and under each arm. A sound probe is placed over the artery at each of these areas to produce the scan for expert examination. Our proposed study will examine the role of ultrasound in diagnosing GCA. We will recruit 402 patients with suspected GCA in whom we would normally perform a biopsy. All patients will have an ultrasound examination in addition to biopsy within a week of starting steroids. Patients will be treated according to usual practice. After six months, we will be in a better position to confirm whether or not they have GCA. We will then look at the accuracy of ultrasound compared with biopsy and also see if there are any benefits of performing both ultrasound and biopsy for identifying patients who do or do not have GCA.