**5. Brachial plexus**

Guidelines for contouring brachial plexus has been put forward by Hall et al. They have put forward step-by-step technique. The contour starts form the neural foramina of C5-T1. It extends from outer edge of spinal canal to the space between anterior and middle scalene. Where no spinal foramina was present, only the space between anterior and middle scalene is contoured. The middle scalene will end in the region of the subclavian neurovascular bundle. In the lower part, the brachial plexus is contoured in the posterior aspect of neurovascular bundle in the inferior and lateral aspect one to two slices below the clavicle.

*Dose recommendations:* Dmax <60Gy. Emami et al. [17] has suggested TD 5/5 for the entire brachial plexus to be 60Gy. More recent studies with longer follow-up (upto 20 years) have shown that the risk of plexopathy keeps rising even after 5 yrs. and may not be apparent until 20 years after radiation [18].
