Diaphragmatic contraction is controlled by phrenic nerve which consists of anterior rami of 3rd- 5th cervical nerve roots. Usually, It can't be evaluated from history taking and physical examination. Thus the diaphragmatic elevation on chest radiograph is assumed to identify the phrenic nerve dysfunction. Normally, the right diaphragm is higher than the left side about 1.5 ± 0.9 centimeters or 0.5 ± 0.3 time of vertebral height. Although there are several methods to determine the diaphragmatic elevation from previous studies, the accuracy, reliability, intra and inter-observer variation are problem.