Role of FIESTA combined with conventional MRI in the evaluation of traumatic brachial plexus roots injury

Abstract

PurposePurpose was to evaluate the role of Fast imaging employing steady-state acquisition (FIESTA) together with conventional MR sequences in the evaluation of traumatic brachial plexus roots injury compared to post contrast MR and Spin Echo MR myelographic studies. Patients and methodsIn this prospective study, 16 patients with a mean age of 17.9y who presented with traumatic brachial plexus roots injury in motor cycle and car accidents were studied with FIESTA, conventional MR, post contrast MR and MR myelography sequences. Imaging findings included: pseudo-meningocele/hemorrhage near the nerve root exit, failure of visualization of the nerve root (dorsal, ventral or both), retracted avulsed nerve root ends, spinal cord edema, and para spinal muscles edema and hemorrhage. Diagnostic accuracy was calculated for each MR sequence. Imaging findings were compared with the gold standard operative findings. ResultsFIESTA combined with conventional MR depicted pseudomeningoceles, non visualized nerve roots, cord displacement, and para spinal muscles abnormalities in 15 patients (93.8%), cord edema in four patients (25%). Pre and post contrast MR detected pseudomeningoceles and non visualized nerve roots in 13 patients (81.3%) while Spin Echo myelography detected pseudomeningoceles and non visualized nerve roots in 14 patients (87.5%). FIESTA combined with conventional MR showed the highest diagnostic accuracy (93.8%) compared to pre and post MR (81.3%) and Spin Echo myelography (87.5%). ConclusionIt is crucial to differentiate between preganglionic and postganglionic injuries for optimal treatment planning in patients with BPI. Conventional MR imaging yielded suboptimal information regarding the fine details of nerve roots’ injury. MR myelography showed some artifacts that decreased overall diagnostic accuracy, FIESTA combined with conventional MR depicted nerve segments in greater detail and provided important information about the relationship of the nerves to nearby structures, it provided high contrast resolution between cerebrospinal fluid and solid structures, allowing the reconstruction of elegant multi-planar images that highlight the injured nerves. Contrast study is recommended in mild trauma cases with normal morphological study.