. 2020 Oct 22;15(10):e0239561. doi: 10.1371/journal.pone.0239561

Table 2. Histomorphometric bidimensional and immunostained derived parameters.

Wall area (WA) (μm²)	Area included between the external perimeter and the lumen perimeter, calculated as difference between total measured area and lumen area
Wall area %	Wall area expressed as a percentage of the total measured area, calculated as follows: (WA/TA) *100
Medial area (MA) (μm²) ^a	Area included between the external perimeter and the internal perimeter, calculated as difference between total measured area and internal area
Medial area %	Medial area expressed as a percentage of the total measured area, calculated as follows: (MA/TA) *100
Intimal area (ImA) (μm²) ^a	Area included between the internal perimeter and the lumen perimeter, calculated as difference between internal area and lumen area
Intimal area %	Intimal area expressed as a percentage of the total measured area, calculated as follows: (ImA/TA) *100
GLA/ED ratio	Ratio between greatest longitudinal axis (GLA) and external artery diameter (ED)
Narrowing index	Index of artery collapse estimated as the ratio between the total measured area (TA) and the theoretical area. The theoretical area represents the area of the fully distended artery obtained from a theoretical diameter calculated as follows: external perimeter (EP)/π
α-SMA positive wall area % (α-SMA + area %, PASM mass)	Wall area positive for the α-SMA immunostaining, expressed as a percentage of the total measured area of the vessel, calculated as follows: (∑p_α-SMA+ /∑p_vessel)*100
α-SMA negative wall area % (α-SMA—area %, ECM mass)	Wall area negative for the α-SMA immunostaining, expressed as a percentage of the total measured area of the vessel, calculated as follows: (∑p_α-SMA- /∑p_vessel)*100

^aAssessed only on sections stained with Movat Russell pentachrome (study 2).