Table 3.
Advantages and disadvantages of devices that determine blood flow status in diabetic foot ulcer
|
|
Advantages
|
Limitations
|
| Assessment of disease severity | ||
| ABI (normal range 1.1-1.3) | Widely used, easy to measure | Unreliable in patients with severe PAD, DFU[26] |
| TBI (normal range 1.0-1.1) | Compensating for ABI limitations, easy to repeat measurement | Decreased accuracy at severe vessel calcification, limitation of diagnostic threshold[27] |
| Continuous wave Doppler | High accuracy in PAD diagnosis[28] | Decreased accuracy in DFU[28] |
| Pulse volume recording | Used in PAD diagnosis | Unable to determine exact location, many other variables[29] |
| Assessment of morphological distribution | ||
| Duplex ultrasound | Noninvasive | Complemented by more detailed image required |
| Angiography | Detailed images can be provided, fast | Vulnerable to artifacts, risk for contrast nephropathy |
| Assessment of regional tissue perfusion | ||
| TcpO2 (normal range 40-70 mmHg) | More sensitive than ABI | DFU, autonomic neuropathy, low accuracy for severe vascular calcification[12] |
| Skin perfusion pressure | Useful when ABI, TBI are not possible | Requires special equipment and further validation[30] |
| Fluorescence angiography | Low toxicity compared with angiography, good discriminatory ability[31] | Expensive, requires special equipment |
| Laser Doppler | Evaluate blood flux rather than blood flow | Vulnerable to motion artifacts and temperature changes, inter-operator variation |
| Hyperspectral imaging | Useful for determining the effect of DFU treatment | Lack of research on interpretation of results[32] |
| Molecular imaging | ||
| PET and SPECT | High resolution | Expensive, requires special equipment |
| Contrast-enhanced ultrasound | Excellent for PAD discrimination[33] | Low accuracy for DFU[33] |
| Multi-modal MRI | Semi-quantitative evaluations based on relative patient conditions are possible | Take long time, no evidence of effectiveness for DFU |
ABI: Ankle-brachial index; DFU: Diabetic foot ulcer; MRI: Magnetic resonance imaging; PAD: Peripheral artery disease; PET: Positron emission tomography; SPECT: Single-photon emission computed tomography; TcpO2: Transcutaneous oxygen pressure; TBI: Toe brachial index.