Not preserved in modified radical mastectomy is
**Core Concept**
Modified radical mastectomy (MRM) is a surgical procedure that involves the removal of the breast tissue, the underlying fascia of the pectoralis major muscle, and a number of axillary lymph nodes. The preservation of certain structures is crucial to maintain the integrity and function of the surrounding tissues.
**Why the Correct Answer is Right**
The correct answer involves the preservation of the **serratus anterior muscle** during a modified radical mastectomy. The serratus anterior muscle plays a vital role in stabilizing the scapula and facilitating movements such as forward elevation of the arm. Preserving this muscle is essential to maintain the patient's range of motion and prevent complications such as winged scapula.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not mentioned in the context of modified radical mastectomy.
**Option B:** This option is a common structure removed during mastectomy, not preserved.
**Option C:** This option is not directly related to the preservation of structures during modified radical mastectomy.
**Clinical Pearl / High-Yield Fact**
It is essential for surgeons to carefully dissect and preserve the serratus anterior muscle during modified radical mastectomy to maintain the patient's shoulder function and prevent long-term complications.
**Correct Answer:** B. Axillary vein