An IMA retractor set is a surgical tool used in cardiothoracic surgery, particularly for Coronary Artery Bypass Grafting (CABG) procedures, to retract the sternum after a mid-sternotomy to provide access and visualization of the internal mammary artery. This specialized retractor, sometimes called a sternal retractor, has a self-retaining mechanism that expands the thoracic cavity, freeing the surgeon's hands to harvest the artery for the graft. 

Cardiac and Thoracic Surgery:

The main use of an IMA retractor is in procedures involving the chest and heart.

CABG Procedures:

It is essential for harvesting the internal mammary artery (IMA) to be used as a graft in coronary artery bypass surgery.

Mid-Sternotomy Access:

It provides clear exposure of the thoracic cavity and internal organs after a mid-sternotomy (a surgical incision through the sternum).