eripheral Vascular Diagnosis Solution for Ankle Brachial Index (ABI) - Medical / Health Care

Ankle Brachial Index (ABI) test assists in the early detection of Peripheral Arterial Disease (PAD) and provides information about its functional severity. During the ABI test, the primary Systolic pressures are measured in each of the right and left brachials, as well as at the level of the right and left ankles. Ankle Brachial Index, or ABI, is determined as the ratio between the higher brachial systolic pressure and each of the ankle pressures. Thus, a separate ABI value is obtained for the Right side and the Left sides. Unlike ultrasound imaging modalities which provide anatomical information, ABI assessment provides a direct indication of the physiological severity of the vascular pathology, such as Peripheral Arterial Disease. ABI testing machines are often used for fast and simple screening of the lower limbs, prior to determining if ultrasound imaging is required. Ank

Measuring the Systolic blood pressure with an ABI machine is simple and requires blood pressure cuffs and a sensor. 

Once a blood pressure cuff is wrapped around the measured site, a distal Doppler or Photoplethysmograph (PPG) waveform is obtained. The cuff is then inflated until the distal signal disappears as a result of the total occlusion. The blood pressure cuff is then deflated in a controlled manner, and the pressure at which the distal signal re-appears is determined as the systolic pressure.

An extension to the basic ABI test is the complete noninvasive physiologic studies of lower extremity arteries. It includes placing cuffs not only on the Ankles but also on other segments of the legs. This type of test is detailed in the Segmental Blood Pressures section. 

Another important extension is performing ABI before and after an induced stress activity such as walking, treadmill, and tiptoes. This type of test is detailed in the Exercise Stress TestTest section. 

Using Doppler to measure the distal waveform is the traditional and clinically accepted method. Usually, ABI is calculated at both Doraslis Pedis Artery and Posterior Tibial Artery. The higher ABI on each side is then taken as the final result to assess Peripheral Arterial Disease (PAD) severity in each leg. Furthermore, Doppler measurement is the recommended clinical method to receiving full reimbursement on CPT codes 93922, 93923, and 93924. The different codes differ in their level of complexity, but all are based on the ABI Doppler method. 

Other methods for testing ABI are Photoplethysmograph (PPG) sensors and Oscillometric devices. Both are less accurate than the Doppler, especially under challenging conditions, which is likely why these methods are not reimbursable under CPT Codes 9392#.

Receiving full reimbursement for this test, especially for CPT Code 93924, may prove difficult or impossible with the less accurate methods such as PPG and Oscillometry. The accepted method uses a diagnostic device such as the Falcon/PRO that provides integrated protocols and reporting for ABI on both Dorsalis Pedis and Posterior Tibial, Segmental Blood Pressures, and Treadmill test.