Comparison of bone lesion distribution between prostate cancer and multiple myeloma with whole-body MRI.

PURPOSE: To assess the distribution of bone lesions in patients with prostate cancer (PCa) and those with multiple myeloma (MM) using whole-body magnetic resonance imaging (MRI); and to assess the added value of four anatomical regions located outside the thoraco-lumbo-pelvic area to detect the presence of bone lesions in a patient-based perspective. MATERIALS AND METHODS: Fifty patients (50 men; mean age, 67±10 [SD] years; range, 59-87 years) with PCa and forty-seven patients (27 women, 20 men; mean age, 62.5±9 [SD] years; range, 47-90 years) with MM were included. Three radiologists assessed bone involvement in seven anatomical areas reading all MRI sequences. RESULTS: In patients with PCa, there was a cranio-caudal increasing prevalence of metastases (22% [11/50] in the humeri and cervical spine to 60% [30/50] in the pelvis). When the thoraco-lumbo-pelvic region was not involved, the prevalence of involvement of the cervical spine, proximal humeri, ribs, or proximal femurs was 0% in patients with PCa and≥4% (except for the cervical spine, 0%) in those with MM. CONCLUSION: In patients with PCa, there is a cranio-caudal positive increment in the prevalences of metastases and covering the thoraco-lumbo-pelvic area is sufficient to determine the metastatic status of a patient with PCa. In patients with MM, there is added value of screening all regions, except the cervical spine, to detect additional lesions.

MRI detection of radiographically occult fractures of the hip and pelvis in the elderly: Comparison of T2-weighted Dixon sequence with T1-weighted and STIR sequences.

PURPOSE: To compare the diagnostic performance of T2-weighted Dixon, T1-weighted and Short-Tau Inversion Recovery (STIR) MR images for the detection of radiographically occult fractures (ROF) of the hip and pelvis in elderly patients after low-energy trauma. MATERIALS AND METHODS: A total of 22 patients older than 50 years with suspected ROF after low-energy trauma was prospectively included. There were 9 men and 13 women, with a mean age of 80.9 years±12.5 (SD) (range: 52-100 years). T2-weighted Dixon, T1-weighted and STIR MR images were analyzed by 3 independent radiologists blinded to the clinical data and the results of other imaging examinations. Readers separately assessed each series of images for the presence of fractures on a per bone analysis. Diagnostic performance of each reader was compared for Dixon and non-Dixon sequences using contingency tables and McNemar test. Interobserver agreement was evaluated according to the Fleiss-Cuzick's kappa statistics. RESULTS: The sensitivity of the Dixon sequence in the detection of ROF ranged from 90.9% (20/22; 95% CI: 70.8-98.9%) to 100% (22/22; 95% CI: 84.6-100%). The sensitivities of the non-Dixon sequences in the detection of ROF ranged from 95.5% (21/22; 95% CI: 77.2-99.9%) to 100% (22/22; 95% CI: 84.6-100%). For each reader, there were no statistical differences between combined Dixon and combined non-Dixon images for the detection of ROF (P=0.12, 0.99 and 0.99). Interobserver agreement with T2-weighted Dixon water-only images was significantly lower than that with the STIR sequence (0.70-0.79 vs. 0.87-0.93). CONCLUSION: T2-weighted Dixon may be a second-rate alternative to T1-weighted and STIR sequences for the detection of ROF of the hip and pelvis in elderly patients.

Familial adhesive arachnoiditis associated with syringomyelia.

Adhesive arachnoiditis is a rare condition, often complicated by syringomyelia. This pathologic entity is usually associated with prior spinal surgery, spinal inflammation or infection, and hemorrhage. The usual symptoms of arachnoiditis are pain, paresthesia, and weakness of the low extremities due to the nerve entrapment. A few cases have had no obvious etiology. Previous studies have reported one family with multiple cases of adhesive arachnoiditis. We report a second family of Belgian origin with multiple cases of arachnoiditis and secondary syringomyelia in the affected individuals.

MRI for response assessment in metastatic bone disease.

BACKGROUND: Beyond lesion detection and characterisation, and disease staging, the quantification of the tumour load and assessment of response to treatment are daily expectations in oncology. METHODS: Bone lesions have been considered "non-measurable" for years as opposed to lesions involving soft tissues and "solid" organs like the lungs or liver, for which response evaluation criteria are used in every day practice. This is due to the lack of sensitivity, specificity and measurement capabilities of imaging techniques available for bone assessment, i.e. skeletal scintigraphy (SS), radiographs and computed tomography (CT). RESULTS: This paper reviews the possibilities and limitations of these techniques and highlights the possibilities of positron emission tomography (PET), but mainly concentrates on magnetic resonance imaging (MRI). CONCLUSION: Practical morphological and quantitative approaches are proposed to evaluate the treatment response of bone marrow lesions using "anatomical" MRI. Recent developments of MRI, i.e. dynamic contrast-enhanced (DCE) imaging and diffusion-weighted imaging (DWI), are also covered. KEY POINTS: • MRI offers improved evaluation of skeletal metastases and their response to treatment. • This new indication for MRI has wide potential impact on radiological practice. • MRI helps meet the expectations of the oncological community. • We emphasise the practical aspects, with didactic cases and illustrations.