Which of the following structure is not found at the Transpyloric plane?
**Core Concept**
The Transpyloric plane, also known as the Third lumbar vertebra (L3), is a significant anatomical landmark in the abdominal cavity. It serves as a reference point for various abdominal structures and their relationships. The structures at this plane are crucial for understanding gastrointestinal, vascular, and other abdominal pathologies.
**Why the Correct Answer is Right**
The Transpyloric plane typically contains the pyloric antrum of the stomach, the beginning of the duodenum, the distal abdominal aorta, the common bile duct, the pancreatic head, and the superior mesenteric artery. These structures are either directly related to the pylorus or are closely associated with it. The correct answer is not found at this plane due to its specific anatomical location.
**Why Each Wrong Option is Incorrect**
**Option A:** The pyloric antrum is indeed found at the Transpyloric plane. It is the distal portion of the stomach that connects to the duodenum.
**Option B:** The common bile duct is typically located at the Transpyloric plane, where it joins the pancreatic duct to form the ampulla of Vater.
**Option C:** The superior mesenteric artery is also found at the Transpyloric plane, where it arises from the aorta and gives off branches to the small intestine.
**Option D:** The splenic artery typically arises from the celiac trunk, which is located at the level of the T12 vertebra, below the Transpyloric plane.
**Clinical Pearl / High-Yield Fact**
The Transpyloric plane is an essential landmark for diagnosing conditions such as pyloric stenosis, duodenal ulcers, and pancreatic disorders.
**Correct Answer:** D. The splenic artery.