The first one can be a 6 or G. I have no idea why.
The 2 has an arrow underneath it. I again have no idea why.
The 37253 could be the CPT code for Intravascular ultrasound (noncoronary vessel) during diagnostic evaluation and/or therapeutic intervention, including radiological supervision and interpretation; each additional noncoronary vessel (List separately in addition to code for primary procedure)
Hope that helps.