In superior vena cava obstruction, one of the signs on computed tomography is an arterially enhancing pseudolesion in segment IV adjacent to the falciform ligament due to collateral flow via the veins of Sappey, sometimes termed the “lightbulb sign.” We describe a case where venoplasty was performed to restore flow in superior vena cava with disappearance of the pseudolesion on subsequent computed tomography, thus “switching off the lightbulb.”
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