RPhS cheat sheet

Phlebology Sonography

• Venous anatomy of the lower limb: deep system (common femoral, femoral, deep femoral, popliteal, calf veins), superficial system (great saphenous vein in the saphenous compartment, small saphenous vein in the posterior calf), and perforating veins connecting them; the saphenofemoral junction lies at the fossa ovalis.

• Reflux definition: retrograde flow exceeding 0.5 s in the superficial and deep veins of the leg and 0.35 s in perforating veins, measured with distal augmentation and Valsalva where applicable; the common femoral vein also uses 1.0 s in some standards, so state the criterion used.

• Reflux testing sequence: patient standing or reverse Trendelenburg, probe perpendicular to skin, sample volume placed mid-lumen, color and spectral Doppler during Valsalva (proximal) and manual distal compression-release (distal calf and popliteal).

• Diameter thresholds: great saphenous vein incompetence is commonly reported at >=3 mm at the junction and >=3 mm 3 cm below; small saphenous >=3 mm; perforators >=3.5 mm with outward flow >0.5 s, but diameter alone never diagnoses reflux.

• CEAP classification: C0 no signs, C1 telangiectasia/reticular, C2 varicose veins, C3 edema, C4 skin changes (a pigmentation/eczema, b lipodermatosclerosis/atrophie blanche), C5 healed ulcer, C6 active ulcer; E for etiology (congenital, primary, secondary), A for anatomy, P for pathophysiology (reflux, obstruction, both).

• DVT diagnosis: noncompressibility of the vein is the primary criterion; secondary signs include intraluminal echogenic thrombus, loss of phasic flow with respiration, absent or diminished augmentation, and lack of complete color fill; compress the common femoral and popliteal vein every 1-2 cm along the vessel.

• Normal venous spectral waveform: spontaneous, phasic with respiration (more continuous in the femoral vein, pulsatile near the heart), augments with distal compression, and ceases with Valsalva in a competent proximal system.

• Great saphenous vein mapping before ablation: mark the junction, measure depth from skin, note tortuosity, accessory saphenous branches, and the distance from the junction to the first major tributary; the small saphenous junction with the popliteal vein is variable (may join above or below the knee crease).

• Post-procedural assessment: after endovenous thermal ablation, check for absence of flow in the treated segment, thrombus extension into the deep system (endovenous heat-induced thrombosis, EHIT, graded I-IV by proximity to the junction), and patency of the common femoral vein.