Presentation
Past history of open heart surgery and CV line insertion. Now the patient complains of dyspnea, facial swelling and headache.
Patient Data
Intensely enhancing area within segment IV which represents the "Hot spot sign". Note a dilated paraumblical vein anterior to the liver.
Superior vena cava obstruction (along its lower portion), with markedly attenuation of its upper segment. Dilated azygous and hemiazygous veins (collateral pathway).
Multiple subcutaneous venous collaterals are seen at the chest wall and anterior abdominal wall.
The lung fields are unremarkable.
Case Discussion
Hot spot sign occurs secondary to superior vena cava obstruction and portosystemic venous shunting between the superior vena cava and the left portal vein via the internal mammary and paraumbilical veins along the ligamentum teres.
The focal hepatic hot spot sign can also be seen on the Technetium-99m sulfur colloid scans of the liver and spleen as a focal area of increased radiopharmaceutical uptake in the medial segment of the left hepatic lobe (segment IV).