[Utility of coronal oblique slices in cervical spine MRI: Improved detection of the neuroforamina]

Coronal oblique orientation of the neural foramen improves cervical spine MRI: A comparison of the sensitivity of different angulations

OBJECTIVE

Angulated projections are used in radiography to show the cervical neural foramen. Imaging the coronal oblique planes in an MRI of the cervical spine should therefore improve visualization of neural foramen pathology. This has to be demonstrated.

PATIENTS AND METHODS

A multi-center investigation of 40 patients with monoradiculopathy and 10 healthy controls was undertaken. T2-weighted sagittal, coronal oblique and axial slices were individually and separately examined by four readers blinded to the diagnosis. The statistical evaluation compared against the clinical gold standard of the neurological diagnosis of a single nerve root irritation or lesion.

RESULTS

The sensitivity/specificity required to detect the relevant neural foramen pathology was 0.47/0.60 for axial, 0.57/0.90 for sagittal and 0.55/0.70 for coronal oblique scans. The readers felt significantly more confident in attributing the cause of pathology using coronal oblique planes. Interreader reliability was moderate to substantial, with the highest values for the sagittal planes (0.39-0.76) and lower values for the transversal and coronal oblique planes (0.15-0.63). Intrareader reliability was substantial, with values between 0.53 and 0.88. Reading the axial planes was significantly more time consuming than reading the other planes.

CONCLUSION

The use of coronal oblique planes in cervical spine MRIs increases sensitivity and confidence in attributing the cause of neural foramen obstruction. They are easy to interpret and demand less reading time than axial planes, and so the inclusion of coronal oblique planes in the workup of cervical spine MRI is recommended, at least when neural foramen pathology is suspected.

Diagnostic Quality of 3D T2-SPACE Compared with T2-FSE in the Evaluation of Cervical Spine MRI Anatomy

BACKGROUND AND PURPOSE

Spinal anatomy has been variably investigated using 3D MRI. We aimed to compare the diagnostic quality of T2 sampling perfection with application-optimized contrasts by using flip angle evolution (SPACE) with T2-FSE sequences for visualization of cervical spine anatomy. We predicted that T2-SPACE will be equivalent or superior to T2-FSE for visibility of anatomic structures.

MATERIALS AND METHODS

Adult patients undergoing cervical spine MR imaging with both T2-SPACE and T2-FSE sequences for radiculopathy or myelopathy between September 2014 and February 2015 were included. Two blinded subspecialty-trained radiologists independently assessed the visibility of 12 anatomic structures by using a 5-point scale and assessed CSF pulsation artifact by using a 4-point scale. Sagittal images and 6 axial levels from C2-T1 on T2-FSE were reviewed; 2 weeks later and after randomization, T2-SPACE was evaluated. Diagnostic quality for each structure and CSF pulsation artifact visibility on both sequences were compared by using a paired t test. Interobserver agreement was calculated (κ).

RESULTS

Forty-five patients were included (mean age, 57 years; 40% male). The average visibility scores for intervertebral disc signal, neural foramina, ligamentum flavum, ventral rootlets, and dorsal rootlets were higher for T2-SPACE compared with T2-FSE for both reviewers (P < .001). Average scores for remaining structures were either not statistically different or the superiority of one sequence was discordant between reviewers. T2-SPACE showed less degree of CSF flow artifact (P < .001). Interobserver variability ranged between -0.02-0.20 for T2-SPACE and -0.02-0.30 for T2-FSE (slight to fair agreement).

CONCLUSIONS

T2-SPACE may be equivalent or superior to T2-FSE for the evaluation of cervical spine anatomic structures, and T2-SPACE shows a lower degree of CSF pulsation artifact.