Low diagnostic accuracy and inter-observer agreement on CT and MRI in diagnosis of spinal fractures in multiple myeloma.

Viktor Dalen,Anne-Sofie Vegsgaard Olsen,Anders E A Dahm,Claude-Pierre Jerome,Jonn-Terje Geitung

doi:10.4081/hr.2021.9037

Viktor Dalen, Anne-Sofie Vegsgaard Olsen + Show 3 more

Open Access

https://doi.org/10.4081/hr.2021.9037

Copy DOI

Abstract

Skeletal disease is common in multiple myeloma. We investigated the inter-observer agreement and diagnostic accuracy of spinal fractures diagnosed by computer tomography (CT) and magnetic resonance imaging (MRI) from 12 myeloma patients. Two radiologists independently assessed the images. CT, MRI, and other images were combined to a gold standard. The inter-observer agreement was assessed with Cohen’s kappa. Radiologist 1 diagnosed 20 malignant spinal fractures on CT and 26 on MRI, while radiologist 2 diagnosed 12 malignant spinal fractures on CT and 22 on MRI. In comparison the gold standard diagnosed 10 malignant spinal fractures. The sensitivity for malignant fractures varied from 0.5 to 1 for CT and MRI, and the specificity varied from 0.17 to 0.67. On MRI, the specificity for malignant spinal fractures was 0.17 for both radiologists. The inter-observer agreement for malignant spinal fractures on CT was -0.42 (Cohen’s kappa) and -0.13 for MRI, while for osteoporotic fractures it was -0.24 for CT and 0.53 for MRI. We conclude that malignant spinal fractures were over-diagnosed on CT and MRI. The inter-observer agreement was extremely poor.

Highlights

Multiple myeloma is a plasma cell neoplasia which accounts for 1% of all cancers we aimed to find the inter-observer agreement and the diagnostic accuracy of spinal fractures in multiple myeloma patients who had taken CT and MRI
The MRI was a short pro- the two radiologists, the patients were cate- uations regarding malignant fractures tocol with sagittal slices, standard T1W and gorized by whether or not they had any frac- between the two radiologists
Two experienced radiologists

Summary

Introduction

Multiple myeloma is a plasma cell neoplasia which accounts for 1% of all cancers we aimed to find the inter-observer agreement and the diagnostic accuracy of spinal fractures in multiple myeloma patients who had taken CT and MRI. Article tion time 0.5 (low-dose CT) or kV 120 and fractures per patient for each imaging mode. The MRI was a short pro- the two radiologists, the patients were cate- uations regarding malignant fractures tocol with sagittal slices, standard T1W and gorized by whether or not they had any frac- between the two radiologists. Both radioloa standard and STIR T2W using a Phillips ture or no fracture (yes or no). Five months after the initial evalualy tions both the radiologists sat together and used all the information available, previous n images and descriptions, and made a cono sensus for the CT images and the MRI images and combined them to a diagnostic e gold standard.

Diagnostics of fractures

Positive predictive value

The main weakness of the current study