Devoted to diagnostic and interventional spine imaging and therapeutics


Evaluation of Obstetric Brachial Plexopathy: MRI vs CT Myelography 2014

Category General Spine Christin A. Tiegs-Heiden, M.D. Laurence J. Eckel, Neuroradiologist/M.D. Felix E. Diehn, Neuroradiologist/M.D. Kara M. Schwartz, Neuroradiologist Christopher H. Hunt, Neuroradiologist Robert E. Watson John T. Wald, Neuroradiologist Purpose Accurate imaging diagnosis of nerve root avulsions in obstetric brachial plexus lesions (OBPLs) is essential for treatment planning. CT myelography is the current standard, however its disadvantages include radiation exposure and lumbar puncture for intrathecal contrast administration. MRI lacks these disadvantages. The purpose of this study is to compare MRI to CT myelography for evaluation of OBPLs. Materials & Methods Seven infants underwent evaluation of OBPLs between April 2010 and April 2012. All patients underwent nerve conduction studies, three-dimensional fast MRI imaging with steady state acquisition, and cervical CT myelography. MRI and CT myelography images were reviewed by a fellowship trained neuroradiologist. The presence or absence of nerve roots at C5-C8 and pseudomeningoceles were recorded. EMG findings were recorded and compared to the imaging findings. Results There was concordance between the findings on bSSFP MRI and CT myelography for all patients. Three patients had a single level nerve root avulsion and associated pseudomeningocele, one patient had a two level avulsion and pseudomeningocele, and one patient had a three level avulsion and pseudomeningocele. Two patients had normal examinations. All avulsions were seen as well or better on MRI than on CT myelography. Conclusion We found MRI using bSSFP to be at least equivalent to CT myelography for evaluation of OBPLs. Although a larger study is needed, we believe our study is sufficient to challenge the practice of obtaining CT myelography in infants with OBPLs, and we propose that MRI become the test of choice for evaluation of OBPLs. This would eliminate the need for ionizing radiation and intrathecal contrast in these pediatric patients. References 1. Carvalho GA, Nikkhah G, Matthies C, Penkert G, Samii M. Diagnosis of root avulsions in traumatic brachial plexus injuries: value of computerized tomography myelography and magnetic resonance imaging. J Neurosurg 1997; 86:69-76 2. Chow BC, Blaser S, Clarke HM. Predictive value of computed tomographic myelography in obstetrical brachial plexus palsy. Plast Reconstr Surg 2000; 106:971-977; discussion 978-979 3. Doi K, Otsuka K, Okamoto Y, Fujii H, Hattori Y, Baliarsing AS. Cervical nerve root avulsion in brachial plexus injuries: magnetic resonance imaging classification and comparison with myelography and computerized tomography myelography. J Neurosurg 2002; 96:277-284 4. Malessy MJA, Pondaag W. Obstetric brachial plexus injuries. Neurosurg Clin N Am 2009; 20:1-14, v 5. Steens SCA, Pondaag W, Malessy MJA, Verbist BM. Obstetric brachial plexus lesions: CT myelography. Radiology 2011; 259:508-515 6. Walker AT, Chaloupka JC, de Lotbiniere AC, Wolfe SW, Goldman R, Kier EL. Detection of nerve rootlet avulsion on CT myelography in patients with birth palsy and brachial plexus injury after trauma. AJR Am J Roentgenol 1996; 167:1283-1287