Solid bone tumors of the spine: Diagnostic performance of apparent diffusion coefficient measured using diffusion‐weighted MRI using histology as a reference standard

Abstract

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1034-1042.

Differential Diagnosis of Spine Tumors: My Favorite Mistake

“…1). 5,18 Chemical shift imaging was also used to identify vertebral hemangiomas in equivocal cases because it usually shows significantly decreased signal on the out-ofphase images compared with the increased or minimally increased signal of malignant lesions. 19 Angiography may also be considered for diagnostic and therapeutic purposes to evaluate the intralesional vascularization and feeding/ draining perilesional vessels; typical angiographic features are the enlargement of the vertebral arterioles, multiple blood pools in the capillary phase, and homogeneous opacification extending beyond the hemivertebral territory and involving the whole vertebral body.…”

“…As demonstrated by several studies, spinal metastases and primary malignant SBTs have generally lower ADC values than benign SBTs. 5,[34][35][36] Among primary SBTs, the lowest ADC values are observed in malignant tumors such as lymphomas, multiple myelomas, and Ewing's sarcoma due to the elevated cellularity and very high nuclear-to-cytoplasm ratio of neoplastic tissue. 37,38 Nevertheless, the different groups of SBTs present ranges of ADC values with significant overlap, regardless of the malignant nature of the lesions themselves; moreover, broadly different results were reported regarding the most reliable cutoff ADC values to distinguish benign and malignant SBTs, ranging from 0.95 Â 10 À3 mm 2 /s to 1.37 Â 10 À3 mm 2 /s.…”

“…37,38 Nevertheless, the different groups of SBTs present ranges of ADC values with significant overlap, regardless of the malignant nature of the lesions themselves; moreover, broadly different results were reported regarding the most reliable cutoff ADC values to distinguish benign and malignant SBTs, ranging from 0.95 Â 10 À3 mm 2 /s to 1.37 Â 10 À3 mm 2 /s. 5,[34][35][36] To date, we do not know whether this uncertainty is mainly due to the heterogeneity of SBT subtypes or to other factors, such as the absence of a standard DWI protocol or the practical difficulties encountered in the evaluation of ADC in SBTs.…”

“…However, they may also present as single lesions, hardly distinguishable from primary SBT. 5 Moreover, primary benign SBT may mimic malignant lesions by showing aggressive imaging features.…”

Renal endometriosis mimicking complicated cysts of kidney: report of two cases

“…Without recurrent haemorrhages and concentration of haemoglobin derivatives (deoxyhaemoglobin and methaemoglobin), viscosity of the cyst remains lower and shading sign is unlikely to be observed (17). Diffusion weighted imaging is a MR sequence which provides functional information by probing the random motion of water molecules in biological tissues, also with a quantitative assessment of diffusivity calculated on the ADC map (18)(19)(20)(21)(22)(23). Endometriomas tipically show low ADC values mainly due to "T2 blackout effects", related to the low T2-weigthed signal intensity of the lesions (24).…”