Retro pharyngeal space extends up to which of the following level?
**Core Concept**
The retropharyngeal space is a fascial space located in the neck, extending from the base of the skull to the tracheal bifurcation. It is bounded by the buccopharyngeal fascia anteriorly, the prevertebral fascia posteriorly, and the alar fascia laterally.
**Why the Correct Answer is Right**
The retropharyngeal space extends superiorly to the base of the skull and inferiorly to the tracheal bifurcation, which is at the level of the sternal angle (T5-T6). This space is important in the context of head and neck surgery, as infections or abscesses can spread from the throat into the retropharyngeal space and potentially into the mediastinum.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as the retropharyngeal space does not extend to the level of C6.
* **Option B:** This option is incorrect as the retropharyngeal space does not extend to the level of C1.
* **Option D:** This option is incorrect as the retropharyngeal space does not extend to the level of T1.
**Clinical Pearl / High-Yield Fact**
The retropharyngeal space is often divided into two compartments: the anterior and posterior compartments, separated by the thyrohyoid membrane. Knowledge of this anatomy is crucial for surgical and radiological procedures in the head and neck region.
**Correct Answer: C. T5-T6.