Table 1. Common OCT measurements.

Pre-PCI measurements

Vessel/external elastic membrane (EEM) area: area bounded by the media-adventitia interface

Lumen CSA: area circumscribed by the lumen border

Minimum lumen area (MLA): smallest CSA in the lesion segment

Maximum and minimum EEM diameters: the longest and shortest EEM distances measured through the center of the lumen

Maximum and minimum lumen diameters: the longest and shortest lumen distances measured through the center of the lumen

Proximal and distal reference: the sites with largest lumen areas on either side of the lesion within 10 mm and in the same segment

Plaque + media area = EEM CSA − lumen CSA

Plaque burden = (EEM CSA − lumen CSA)/EEM CSA ×100

Lumen area stenosis: (the reference lumen CSA − minimal lumen CSA)/reference lumen CSA ×100

Post stenting measurements

Stent CSA: area circumscribed by the stent border

Proximal and distal reference: the sites with largest lumen areas on either side of the stent and within 5 mm of the edges

Maximum (Max) and minimum (Min) stent diameters (SD): the longest and shortest diameters measured through the center of the stent

Minimum stent CSA = smallest stent CSA

Stent expansion: minimum stent CSA in correlation with reference lumen CSA (proximal, distal or average)

Stent symmetry = (Max SD − Min SD)/Max SD

Neointimal area = Stent CSA − lumen CSA

In-stent lumen area stenosis = (the reference lumen CSA − minimal lumen in-stent CSA)/reference lumen CSA ×100

Maximum and minimum neointimal thickness: the longest and shortest dimensions between the lumen border of the neointima to the adluminal stent border along the line passing through the center of the lumen

% neo intimal area = Neointimal CSA/stent CSA

OCT, optical coherence tomography; PCI, percutaneous coronary intervention; CSA, cross-sectional area.