Figure 8.

[Section 4.2] Recommendations for evaluation of suspected lower extremity recurrent DVT: evaluation following nondiagnostic proximal US and prior US result available for comparison. Where there are preferred strategies, these are indicated by boldface print; less preferred strategies are indicated by italicizing/shading. §See Kearon et al.¹¹ #Previous US with residual diameter measurements is available for comparison. Current US is nondiagnostic (technically limited or only abnormality an area of prior noncompressibility with increase in residual venous diameter of < 4 mm but ≥ 2 mm). £“Negative” refers to a normal US or an area of prior noncompressibility with a stable or decreased residual diameter or an interval increase in residual diameter of < 2 mm. &“Positive” refers to a new noncompressible segment or an area of prior noncompressibility with an interval increase in residual diameter of $ 4 mm. ^aGrade 1B vs treating for DVT and vs alternative test strategies. ^bGrade 2B vs treating for DVT and vs alternative test strategies. ^cGrade 2B vs treating for DVT and vs alternative test strategies. ^dGrade 2B vs no further testing and vs venography. ^eGrade 1B vs further testing with venography. ^fGrade 1B for treating DVT vs venography if new noncompressible segment in the common femoral or popliteal vein; Grade 2B for treating DVT vs venography for a ≥ 4-mm increase in venous diameter during compression compared with that in the same venous segment on a previous result. ^gGrade 2B for treating DVT over venography if a ≥ 4-mm increase in venous diameter during compression compared with that in the same venous segment on a previous result (Grade 1B for treating DVT over venography if new noncompressible segment in the common femoral or popliteal vein). ^hGrade 2B for repeat proximal US in 1 week or moderate or highly sensitive D-dimer over treating for DVT (Grade 1B for venography over treating for DVT). See Figure 1 legend for expansion of abbreviation.