Recom-. G-9.

Recommendation	Grade	Level of evidence	Key references
Anticoagulation is not recommended in isolated superficial vein thrombosis of <5 cm in lower extremity if there is no risk such as malignancy, thrombophilia, or proximity to the deep venous system.	Not recommended (III)	C	Kakkos et al.[32]
In the lower extremity superficial vein thrombosis case, when acute inflammation and prothrombotic process improve, endovenous ablation procedures should be considered (>3 months).	Strong recommendation (IIa)	C	Kakkos et al.[32]
Fondaparinux 2.5 mg or rivaroxaban 10 mg recommended if superficial vein thrombosis of the lower extremity is >3 cm from the deep vein and is >5 cm long	Very strong recommendation (I)	B	Decousus et al.[57 Beyer-Westendorf et al.[56]
If the lower extremity superficial vein thrombosis is >3 cm from the deep vein and >5 cm in length, LMWH should be considered as an alternative.	Strong recommendation (IIa)	B	Duffett et al.[55] Nikolakopoulos et al.[58]
If the lower extremity superficial vein thrombosis is >3 cm from the deep vein and >5 cm in length, anticoagulation for 45 days is recommended.	Very strong recommendation (I)	B	Decousus et al.[57]Beyer-Westendorf et al.[56] Duffett et al.[55]
Therapeutic anticoagulation is recommended if the lower extremity superficial vein thrombosis is <3 cm from the deep vein.	Very strong recommendation (I)	C	Kakkos et al.[32]
Three months of treatment may be considered in clinically or anatomically risky patients.	Weak recommendation (IIb)	C	Nikolakopoulos et al.[58]
LMWH: Low molecular weight heparin.