Table 5: Sensitivity, specificity, predictive values, and accuracy of duplex ultrasound findings in diagnosis of infrapopliteal arterial lesions.
|
Sensitivity |
Specificity |
PPV |
NPV |
Accuracy |
|
Ultrasound finding |
||||||
1. Color Doppler ultrasound |
79.0% (94/119) |
66.7% (42/63) |
81.7% (94/115) |
62.7% (42/67) |
74.7% (136/182) |
|
2. Increased in PSV ≥ two-fold relative to the proximal segment |
85.7% (48/56) |
46.8% (59/126) |
41.7% (48/115) |
88.1% (59/67) |
58.8% (107/182) |
|
3. Monophasic flow and broadening spectrum at the examined segment |
64% (87/136) |
39.1% (18/46) |
75.6% (87/115) |
26.9% (18/67) |
57.7% (105/182)
|
|
4. Monophasic flow with reduced velocity at the distal segment |
70% (7/10) |
44% (33/75) |
14.3% (7/49) |
91.7% (33/36) |
47.1% (40/85) |
|
Combining two ultrasound findings |
||||||
1 + 2 |
84.9% (45/53) |
45.7% (59/129) |
39.1% (45/115) |
88.1% (59/67) |
57.1% (104/182) |
|
1 + 3 |
79.1% (72/91) |
53.3% (48/90) |
62.6% (72/115) |
71.6% (48/67) |
65.9% (120/182) |
|
Combining three ultrasound findings |
||||||
1 + 2 + 3 |
87.6% (85/97) |
64.7% (55/85) |
73.9% (85/115) |
82.1% (55/67) |
76.9% (140/182) |