Detection of Soft-Tissue and Skeletal Infections with Ultra Low-Field (0.02 T) Mr Imaging

Abstract

To evaluate the use of ultra low-field (0.02 T) magnetic resonance (MR) imaging in the diagnosis of musculoskeletal infection, MR examinations with T2 weighted sequences were performed in 61 patients thought to be suffering from one of four major diagnostic categories: Soft-tissue abscesses (n=22), osteomyelitis (n=21), septic arthritis (n=9) and spondylitis (n=9). Infection was confirmed for 37 of these 61 patients. The verified abscesses, arthritis, spondylitis and acute osteomyelitis could be detected by 0.02 T MR. The sensitivity was poor in cases of chronic osteomyelitis. There was one false positive finding in a patient with a possible soft tissue infection. The 0.02 T MR examination failed four times. Two patients were too heavy and another 2 patients had magnetic material in or near the scanning field. Compared with computed tomography and isotope scanning, 0.02 T MR proved a little more informative, but without any statistical significance.

The development of musculoskeletal radiology for 100 years as presented in the pages of Acta Radiologica

“…MRI was quickly adopted as an important imaging modality for musculoskeletal use, and as the image quality improved and imaging time decreased, the number of articles in Acta Radiologica rapidly increased (126). For example, spinal imaging was first reported in 1987 (127), hemophilic arthropathy in 1987 (128), a comparison of low-field MRI with scintimetry for evaluation of posttraumatic femoral head avascular necrosis (129), and an evaluation of soft-tissue infection by ultra-low-field MRI in 1989 (130), and the use of gadolinium contrast for investigation of soft-tissue tumors in 1990 (131). Today, the ubiquitous use of MRI is evident in the large proportion of the published articles in Acta Radiologica.…”

“…Radiologic changes from diseases that are today rare in high-income countries were reported early on, such as tetanus in 1938 (147), syphilis in 1945 (148), leprosy in 1950-1952 (149)(150)(151), and poliomyelitis in 1957 (152). The publications in later years have mostly focused on the ability of newer modalities to diagnose and follow up an infection before and after treatment (83,130,(153)(154)(155), especially after spinal surgery (156,157), with some reports also on parasitic diseases (158)(159)(160)(161).…”

Complicated Bone and Soft-Tissue Infections

“…Low-field MR, with field strengths below 0.5 T, mostly within the range of 0.1-0.25 T, is increasingly being used (25,28). Soft-tissue and bone infections have been detected successfully even with ultra low-field (0.2 T) units (12).…”