Volumetric T2-weighted MRI improves the diagnostic accuracy of spinal vascular malformations: comparative analysis with a conventional MR study

摘要

Background To date, very little study of the importance of a volumetric T2-weighted MR sequence in the evaluation of spinal vascular malformations (SVMs) has been carried out. Objective To determine the utility and accuracy of a volumetric T2 MR sequence compared with conventional T2 in the diagnosis of SVMs. Methods Retrospective analysis of all patients who underwent spinal DSA for suspected SVMs was conducted. Conventional T2 and volumetric T2 MR images were analysed for the presence of flow voids and parenchymal changes, and SVMs were characterized. The sensitivity, specificity, and overall diagnostic accuracy of these MRI diagnoses were calculated. Results Of 89 subjects included in the final analysis, 70 patients had angiographically proved SVMs (38 patients with spinal cord arteriovenous malformations [SCAVM-intramedullary or perimedullary] and 32 cases of spinal dural arteriovenous fistula (SDAVF)) and the remaining 19 subjects were normal. The sensitivity and specificity for identification of SVMs were 98.1% and 90% for volumetric T2 sequences, compared with 82.8% and 89.4% for conventional T2 MRI, respectively. For characterization of spinal vascular lesions, volumetric MRI showed high sensitivity, specificity, and accuracy for SDAVF (100%, 90%, 97%, respectively) compared with conventional T2 MRI (71.8%, 89%, 79%, respectively). The positive likelihood ratio was high and negative likelihood ratio was zero for volumetric MRI evaluation of SDAVF, while these ratios were comparable between the two sequences for SCAVM. Conclusion Volumetric T2 MRI is highly sensitive for the detection of SVMs, especially for SDAVF. Volumetric T2 MRI could be introduced into routine clinical practice in the screening of suspected SVMs.