MR Imaging Diagnosis Value Of Brachial Plexus Pre-ganglionic Injury

Objective: To evaluate the value of MR Imaging(MRI) in diagnosing brachial plexus pre-ganglionic injury. Methods: Eighteen cases with brachial plexus injury were included from September 2003 to April 2006 ,which included 12 males and 2 females. Aging from 8 to 36 years(mean age 27 years). Seven of the patients had injured to their left brachial plexus, and eleven to their right. The cases history range from 8 to 272 days(mean day 106 days). All patients underwent preoperative MRI scanning and electrophysiological examination, then received surgical exploration. Results: the main signs of brachial plexus pre-ganglionic injury respectively were: lack of nerve root(15 cases); post-traumatic spinalmeningocele(16 cases); displacement of spinal(9 cases); deformity of spinal cord(2 cases); and "black line" sign(12 cases). The main signs of brachial plexus in surgical exploration were: Some nerves of post-ganglionic injury had twisted to neuroma; Or the intervertebral foramen was empty, Between anterior and medial scalenus there were some fibrous tissues; Aother performances were nerve rootlets became thicker and much rigid, and In the preface of nerves became paler and cruder. MRI detected 33 injured nerve rootlets, And we had found 41 injured nerve rootlets in surgical exploration. The sensitivity, specificity and accuracy of MRI in diagnosing pre-ganglionic brachial plexus were 93.9%, 75.0% and 90.2% respectively(table 1). Conclusion MRI can show the nerve rootlets within the intervertebral foramen, thus, can make a correct qualitative and level diagnosis in brachial plexus pre-ganglionic injuries.