Intermediate Thoracic Duct Quiz

Q1. What is the usual relationship of the thoracic duct to the aorta as it enters the thorax?

• It enters through the obturator canal
• It runs inside the aortic lumen
• It passes through the caval opening inside the inferior vena cava
• It passes through the aortic hiatus near the aorta

Q2. In the lower posterior mediastinum, where is the thoracic duct commonly positioned?

• Inside the pericardial cavity
• Within the pulmonary artery
• Between the aorta and azygos vein, posterior to the esophagus
• Anterior to the sternum

Q3. At approximately what thoracic level does the thoracic duct usually cross from right to left?

• At the coccyx
• Around L5 only
• Around C1
• Around T5

Q4. Which structure is closely anterior to the thoracic duct in much of the posterior mediastinum?

• Esophagus
• Sternum
• Trachea throughout its entire course
• Right ventricle

Q5. Which major lymphatic territory joins the thoracic duct near its cervical termination?

• Right lumbar trunk only
• Right femoral vein
• Inferior mesenteric artery
• Left jugular and left subclavian lymphatic trunks

Q6. Why does the thoracic duct contain valves?

• To produce lymphocytes
• To digest dietary fat
• To promote one-way lymph flow
• To oxygenate lymph

Q7. What is the functional relationship between intestinal lacteals and the thoracic duct?

• Lacteals ultimately deliver lipid-rich lymph to the thoracic duct
• They have no lymphatic connection
• The thoracic duct secretes lipids into lacteals
• Lacteals empty directly into the portal vein

Q8. Why can the thoracic duct vary in its abdominal origin?

• The cisterna chyli and central abdominal lymphatics are anatomically variable
• The aorta changes sides in every person
• The diaphragm is normally absent
• The duct always begins in the pelvis

Q9. Which sequence best traces lymph from the lower limb to the thoracic duct?

• Inguinal nodes, renal pelvis, ureter, thoracic duct
• Inguinal nodes, axillary nodes, jugular trunk, thoracic duct
• Inguinal and iliac nodes, lumbar nodes, lumbar trunk, thoracic duct
• Popliteal nodes, celiac nodes, portal vein, thoracic duct

Q10. Which sequence best traces dietary lipid from a small-intestinal villus to the venous circulation?

• Lacteal, bile duct, thoracic duct, inferior vena cava
• Lacteal, intestinal lymphatics, thoracic duct, left venous angle
• Lacteal, renal pelvis, ureter, left venous angle
• Lacteal, portal vein, thoracic duct, right atrium