The Clinical Usefulness of Preoperative Imaging Studies to Select Pathologic Level in Cervical Spondylotic Myelopathy: Comparative Analysis of Three-Position MRI and Post-Myelographic CT

Özet

AIM: To compare the accuracy of determining pathologic segment between three-position MRI (3P-MRI) and post-myelographic CT(PMCT) in cervical spondylotic myelopathy (CSM) by assessing the degree of inter-observer and intra-observer agreement.MATERIAL and METHODS: We retrospectively reviewed 3P-MRI and PMCT for the diagnosis of multilevel CSM in 136 patientswho underwent surgery. Using an assessment scale, 8 blind observers with various clinical experiences examined 5 parameters:spinal canal narrowing, foraminal stenosis, bony abnormality, intervertebral disc herniation, and nerve root compression. Spinalcanal, neural foraminal, spinal cord and disc protrusion diameters were measured. Intra-observer and inter-observer agreement ofeach image was analyzed.RESULTS: Spinal canal width and foraminal diameter was found to be significantly smaller in 3P-MRI compared to PMCT. Nosignificant differences of cervical cord diameter and the size of disc protrusion measured in 3P-MRI compared to PMCT wereobserved. Comparing between 3P-MRI and PMCT, disc abnormality and nerve root compression showed better agreement on3P-MRI, whereas foraminal stenosis and bony lesion showed better agreement on PMCT.CONCLUSION: In the present study, PMCT was still useful in diagnosis of the foraminal stenosis and bony lesion compared to3P-MRI but showed limitation in disc abnormality and nerve root compression. Even though PMCT may provide valuable additionalinformation in difficult or ambiguous cases, universal standard of 3P-MRI showed higher reliability in detecting pathologic levels inCSM patients.