True statement about great sphenous vein
**Core Concept**
The great sphenoid vein is a significant venous structure that plays a crucial role in the drainage of the dura mater and the surrounding cerebral tissues. It is a key component of the intracranial venous system, which is responsible for returning deoxygenated blood from the brain to the heart.
**Why the Correct Answer is Right**
The great sphenoid vein is a tributary of the cavernous sinus, which is a dural venous sinus located near the base of the brain. The cavernous sinus receives blood from the great sphenoid vein, as well as from other cerebral veins, and drains into the superior and inferior petrosal sinuses. This anastomotic network allows for the exchange of blood between the cerebral and extracranial venous systems, playing a vital role in regulating cerebral blood flow and pressure.
**Why Each Wrong Option is Incorrect**
**Option A:** The great sphenoid vein is not a direct tributary of the internal jugular vein. While the internal jugular vein is a major venous structure that drains blood from the brain, the great sphenoid vein primarily drains into the cavernous sinus.
**Option B:** The great sphenoid vein is not a superficial vein. Unlike superficial veins, which are located closer to the skin surface, the great sphenoid vein is a deep vein that lies within the dura mater, making it a component of the intracranial venous system.
**Option C:** The great sphenoid vein is not a major venous structure that drains the spinal cord. While the spinal cord has its own venous drainage system, the great sphenoid vein is primarily involved in the drainage of the cerebral tissues.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the cavernous sinus is a critical structure in the intracranial venous system, as it receives blood from multiple cerebral veins, including the great sphenoid vein. Damage to the cavernous sinus can lead to serious complications, such as cavernous sinus thrombosis, which can result in severe headache, vision loss, and even death.
**Correct Answer:** B. The great sphenoid vein is a deep vein that lies within the dura mater, not a superficial vein.