IJSR - International Journal of Scientific Research

Dr. Ankita Gupta; Dr. Naima Mannan; Dr. Usha Jaipal

Volume : VI, Issue : I, January - 2017

Diagnostic accuracy of Contrast enhanced Magnetic Resonance Imaging in bone tumors and its association with surgical findings assuming histopathological findings as gold standard

Dr. Ankita Gupta, Dr. Naima Mannan, Dr. Usha Jaipal

Abstract :

To determine diagnostic accuracy of contrast enhanced MRI in characterization of different primary bone tumors and to find agreement of association between MRI and surgical findings in primary bone tumors, assuming histopathological findings as gold standard. MRI was performed on 3 Tesla Philips system on 120 patients suspected of bone tumors on conventional radiography. Sequences and planes used were T1w and T2w in axial, sagittal, coronal planes, STIR in coronal plane and post contrast Fat saturated T1w images. Biopsy was done and treatment was planned. Post operative resected specimen was sent for histopathological examination. MRI detected marrow involvement with sensitivity, specificity, PPV, NPV, diagnostic efficacy of 98.8%, 62.5%, 94.44%, 83.33%, 93.33% respectively. MRI detected neurovascular bundle involvement with sensitivity, specificity, PPV, NPV, diagnostic efficacy of 92.31%, 96.81%, 88.89%, 97.85%, 95.83% respectively. MRI detected joint involvement with sensitivity, specificity, PPV, NPV, diagnostic efficacy of 87.5%, 91.67%, 72.41%, 96.70%, 90.83% respectively. MRI detected cortical eak with sensitivity, specificity, PPV, NPV, diagnostic efficacy of 88.71%, 77.59%, 80.88%, 86.54%, 83.33% respectively. MRI detected soft tissue involvement with sensitivity, specificity, PPV, NPV, diagnostic efficacy of 92.11%, 88.64%, 93.33%, 86.67%, 90.83% respectively. Although MRI could demonstrate different components of tumor, there was no significant difference in signal intensity patterns of different histological types of tumors. Diagnostic accuracy of MRI for benign and malignant bone tumors against final diagnosis after histopathological examination was 86.67%. Conclusion– Multiplanar imaging capability of MRI helps in delineation of tumor, determine neurovascular bundle involvement, joint involvement, local extent and staging. Accurate preoperative local staging allows planning of limited or limb saving surgery. All lesions raising suspicion for malignancy should be evaluated after gadolinium–based contrast medium injection to optimise border characterisation, separate oedema from active tumour and to determine accurate site for biopsy. (PPV= Positive Predictive Value, NPV= Negative Predictive Value)