We divide our axillary nodes into 3 levels.
Level 1: lateral to pec minor
Level 2: deep to pec minor
Level 3: medial to pec minor
And then there are the nodes that move into the neck space in the supraclavicular fossa.
In terms of morphology a normal node should be oval shaped and have a thin and even coverage of cortex surrounding a fatty hilum.
Suspicious features include: localised area of cortical thickening. Cortex greater than 3mm in diameter (measuring cortex only). Nodes that lose their fatty hilum. Nodes that become round or taller than wide. Nodes that lose their kidney like organised hilar flow pattern of vessels.