The origin of the left gastric artery

Five hundred celiac angiograms were reviewed to evaluate the frequency of clinically significant variations in the origin of the left gastric artery. In 13 of 500 cases, the left gastric artery arose anomalously most often as a direct branch of the aorta; in 14 of 500 cases, the left gastric artery primarily supplied the liver with only minor contributions to the stomach. An aberrant origin of the left gastric artery necessarily influences the angiographic diagnosis and therapy of gastrointestinal hemorrhage.     

The left paratracheal reflection

The left paratracheal reflection, which is found medial to the left subclavian artery reflection, was sought in 302 normal posteroanterior (PA) chest radiographs, 93 conventional chest tomograms, and 113 thoracic computed tomographic (CT) scans. The left paratracheal reflection was visible on 31% of normal PA chest radiographs. Conventional tomography and CT showed that this finding is produced by contact of the lung with the mediastinum anterior to the left subclavian artery. The CT scans studied showed that the left paratracheal reflection actually represents contact of the lung with left paratracheal mediastinal fat 94% of the time, with the proximal 1-2 cm of the lateral wall of the left common carotid artery 5% of the time, and with the left tracheal wall 1% of the time. A variety of entities may alter the left paratracheal reflection.