Miller et al developed an index for describing obstruction to pulmonary perfusion in a patient with pulmonary emboli as seen on pulmonary angiography.
Components of index:
(1) arterial obstruction based on segmental arteries
(2) perfusion of lung zones
|
Main Artery |
Lobar |
Segmental in Lobe |
|
right main |
right upper lobe |
3 |
|
|
right middle lobe |
2 |
|
|
right lower lobe |
4 |
|
left main |
left upper lobe |
2 |
|
|
left lingula |
2 |
|
|
left lower lobe |
3 |
arterial obstruction score =
= SUM(number of segments with any degree of obstructed blood flow)
Perfusion zones:
(1) left upper zone
(2) left middle zone
(3) left lower zone
(4) right upper zone
(5) right middle zone
(6) right lower zone
|
Perfusion |
Points |
|
normal |
0 |
|
moderately reduced |
1 |
|
markedly reduced |
2 |
|
absent |
3 |
perfusion subscore =
= (lung zone) * (perfusion points)
perfusion score =
= SUM(perfusion subscore for all 6 zones)
total score = Miller Index =
= (arterial obstruction score) + (perfusion score)
Interpretation:
• minimum arterial obstruction score: 0
• maximum arterial obstruction score: 16
• minimum perfusion score: 0
• maximum perfusion score: 18
• minimum Miller index: 0
• maximum Miller index: 34
Specialty: Pulmonology
ICD-10: ,
