Introduction: We present the case of a patient suffering from inferior vena cava hypoplasia complicated with Phlegmasia cerulean dolens. Imaging techniques allow precise diagnosis of inferior vena cava hypoplasia, providing essential structural details on the degree of damage of the vena cava and for the other branches. Case presentation: A 58 years old, obese and diabetic male patient presented with intense pain in the lower limbs, with the onset 24h before presentation. The patient presented generalized edema, cyanosis and functional impotence. Angio CT examination revealed hypoplasia of the inferior vena cava, with extensive DVT (deep vein thrombosis). In emergency conditions, with the agreement of the patient, we initiated the thrombolytic therapy (streptokinase for 72h) associated with anticoagulants (heparin). The evolution was favorable: a significant reduction in leg circumference was recorded, together with pain relief and reduction of local inflammation in the lower limbs. Conclusion: Severe cases of inferior vena cava hypoplasia complicated with deep vein thrombosis can present a good prognosis if appropriate treatment with anticoagulants and thrombolytics is initiated in time.