Background
Angiography is an imaging technique used to visualize the lumen of blood vessels and diagnose conditions involving vessel narrowing or blockage. Angiograms can be used to assess blood flow in any area of the body, with peripheral—or extremity—angiograms focusing on the arms and legs. Angiography provides the most objective evaluation of radial, ulnar, and digital vessel status, and digital subtraction angiography (DSA), in particular, is the gold standard for diagnosing ischemic conditions in the hand. The resolution provided by DSA remains unparalleled, and it also allows interventional procedures like thrombolysis or thrombectomy to be performed concomitantly. Thus, peripheral angiograms should be regarded as an important diagnostic tool for scleroderma, Raynaud’s disease/phenomenon, arterial hand injuries, and other vascular conditions affecting the hand and/or wrist.1-3
Historical Overview
Portuguese physician and neurologist Egas Moniz is responsible for developing the angiogram and is recognized as a pioneer in the field. Moniz performed the first successful visualization of a pituitary tumor in a young man with angiography in 1927, and his discovery aroused the interest of other famous neurologists during this time. After describing the normal distribution of intracranial blood vessels, Moniz obtained images indirectly showing through the use of X-rays the location and size of intracranial tumors. This was initially achieved by measuring the displacement of injected arteries produced by the neoplasm, and further developed by Moniz in 1933 with an open indirect method for performing vertebro-basilar arteriography by injecting the contrast into an exposed subclavian artery. Another significant milestone for angiography came in 1953, when Seldinger developed a percutaneous technique for cardiac catheterization, which allowed the procedure to become much safer procedure, as no sharp introductory devices need to remain inside the vascular lumen. A very similar technique is still used today.4,5
Description
Imaging of the hand should first be taken before the angiogram is performed. One standardized technique for upper extremity angiography involves a direct puncture of the brachial artery with a 20-gauge needle, using 20 cc low osmolality or non-ionic contrast medium with an injection velocity of 3 cc/sec. The vasodilating medication, such as tolazoline hydrochloride, is typically diluted in isotonic salt and then injected very slowly into the brachial artery. If no satisfactory vasodilation is achieved, a subsequent 1 mL injection of tolazoline should be given. Once vasodilation is achieved, appropriate X-rays are to be taken. Angiographic findings correspond with the pathologic changes in the arterial wall, with features of some conditions responding to the vasodilation and others remaining fixed.3,6
