Intramedullary tuberculomas are rare (Arseni & Samitca, 1960; Dastur, 1972; Compton & Dorsch, 1984) but have been demonstrated either at surgery or at autopsy. The appearance of tuberculomas in the brain on magnetic resonance imaging (MRI) has been reported (Gupta et al, 1988). However, the image morphology of intrinsic cord tuberculomas has not been described. We present the MR findings in two patients with tuberculomas of the cervical cord diagnosed on the basis of positive therapeutic response to antituberculous therapy (ATT). Two young patients with clinical and radiological evidence of intramedullary pathology, who were referred for MRI study with possibility of tuberculous myelitis, are described. Magnetic resonance imaging of the cervicodorsal spine was performed with a 1.5 T (MAGNETOM, Siemens) system using spin echo sequences (repetition time (TR), 2000 ms and echo time (TE), 69–90 ms for T2 images; TR, 700–800 ms and TE, 17–22 ms for T1 images) in axial and sagittal planes. Images were acquired on 256 × 256 matrix and 1.2 gradient zooming with 5 mm contiguous slices. Follow-up studies in both cases were taken after 4 months and after 1 year in Case 2. from C2 to C5/C6 (Figs la & b). The extradural space and vertebral bodies were found to be normal. The lesion appeared to be hypointense in its periphery with central hyperintensity on T2-weighted images and low to isointense on T1 images. The patient showed remarkable relief of her symptoms over a period of 4 months with ATT.

BackgroundQuantitative assessment of myocardial blood flow (MBF) from cardiovascular magnetic resonance (CMR) perfusion images appears to offer advantages over qualitative assessment. Currently however, clinical translation is lacking, at least in part due to considerable disparity in quantification methodology. The aim of this study was to evaluate the effect of common methodological differences in CMR voxel-wise measurement of MBF, using position emission tomography (PET) as external validation.MethodsEighteen subjects, including 9 with significant coronary artery disease (CAD) and 9 healthy volunteers prospectively underwent perfusion CMR. Comparison was made between MBF quantified using: 1. Calculated contrast agent concentration curves (to correct for signal saturation) versus raw signal intensity curves; 2. Mid-ventricular versus basal-ventricular short-axis arterial input function (AIF) extraction; 3. Three different deconvolution approaches; Fermi function parameterization, truncated singular value decomposition (TSVD) and first-order Tikhonov regularization with b-splines. CAD patients also prospectively underwent rubidium-82 PET (median interval 7 days).ResultsMBF was significantly higher when calculated using signal intensity compared to contrast agent concentration curves, and when the AIF was extracted from mid- compared to basal-ventricular images. MBF did not differ significantly between Fermi and Tikhonov, or between Fermi and TVSD deconvolution methods although there was a small difference between TSVD and Tikhonov (0.06 mL/min/g). Agreement between all deconvolution methods was high. MBF derived using each CMR deconvolution method showed a significant linear relationship (p < 0.001) with PET-derived MBF however each method underestimated MBF compared to PET (by 0.19 to 0.35 mL/min/g).ConclusionsVariations in more complex methodological factors such as deconvolution method have no greater effect on estimated MBF than simple factors such as AIF location and observer variability. Standardization of the quantification process will aid comparison between studies and may help CMR MBF quantification enter clinical use.

Purpose: To evaluate the Akaike information criterion (AIC) model selection technique as a method for detecting differences in microvascular characteristics between tumorous and non-tumor liver tissue. Materials and Methods:The AIC was applied to six patient datasets with liver metastases to determine, on a per voxel basis, which of two physiologically plausible candidate models gave a more appropriate description of the data. The dual-input single-compartment Materne model, extended to incorporate a novel portal input function estimation method, was chosen to represent liver tissue and the single-input dual-compartment extended Kety model was used for tumor.Results: Median AIC probabilities when comparing tumor versus liver and tumor versus tumor-margins were significantly different (P 0.01) in five of the six patient datasets. Comparisons between tumor margins and liver regions were significantly different in four datasets. Median AIC probabilities selected for the extended Kety model in all tumor regions, with the Materne model being progressively more probable through tumor margins into liver. Conclusion:We present a viable method for assessing the spatially varying microvascular characteristics of tumorbearing livers, with possible applications in lesion detection, assessment of tumor invasion, and measurement of drug efficacy.

Accuracy and precision of DCE-MRI parameter estimates are improved when signal models are fit jointly rather than sequentially. Magn Reson Med 76:1270-1281, 2016. © 2015 Wiley Periodicals, Inc.