BACKGROUND AND PURPOSE: Conventional MR imaging techniques cannot produce optimal images of bone structures because bone has little water and a very short T2 life span. The aim of this study was to investigate the clinical feasibility of skull MR imaging using the zero TE sequence in patients with head trauma by assessing its diagnostic image quality and quantitative measurement compared with CT images. MATERIALS AND METHODS: Thirteen enrolled patients with head trauma were assessed using brain CT and skull MR imaging. Image quality was graded on a 5-point Likert scale to compare the 2 modalities. To evaluate quantitative analyses between the 2 imaging modalities, we measured skull thickness and normalized bone tissue signal. Interobserver reliability was assessed using weighted κ statistics and the intraclass correlation coefficient. RESULTS: Both imaging techniques clearly depicted skull fractures in all 13 patients. The mean scores for skull MR imaging and CT were 4.65 ± 0.56 and 4.73 ± 0.45 (P = .157), respectively, with substantial interobserver agreement (P < .05). The 2 imaging modalities showed no difference in skull thickness (P = .092) and had good correlation (r² = 0.997). The mean value of normalized bone tissue signal among the 3 layers of the skull was relatively consistent (P = .401) with high interobserver agreement (P < .001). CONCLUSIONS: Zero TE skull MR imaging has diagnostic image quality comparable with that of CT images. It also provides consistent results on the quantitative measurement of cortical bone with CT images.

BACKGROUND AND PURPOSE: Contrast-enhanced CT protocols for papillary thyroid cancer are yet to be optimized. Our aim was to compare the diagnostic accuracy of arterial phase CT and delayed-phase CT protocols for lateral cervical lymph node metastasis from papillary thyroid carcinoma by using the lymph node tissue attenuation. MATERIALS AND METHODS: This retrospective study included 327 lateral cervical lymph nodes (177 metastatic and 150 benign) from 131 patients with papillary thyroid carcinoma (107 initially diagnosed and 24 recurrences). Patients underwent CT by using 1 of 3 protocols: a 70-second (A) or a 35-second (B) delay with 100 mL of iodinated IV contrast or a 25-second delay with 75 mL of IV contrast (C). Two readers independently measured and compared lymph node tissue attenuation between metastatic and benign lymph nodes. An area under the receiver operating characteristic curve analysis was performed to differentiate metastatic and benign lymph nodes after multiple comparison correction for clustered data and was compared across the protocols. RESULTS: The difference in mean lymph node tissue attenuation between metastatic and benign lymph nodes was maximum in protocol C (P < .001 for both readers). Protocol C showed the highest diagnostic performance (area under the receiver operating characteristic curve, 0.88–0.92) compared with protocol A (area under the receiver operating characteristic curve, 0.73–0.74, P < .001 for both readers) and B (area under the receiver operating characteristic curve, .63–0.65, P < .01 for both readers). The sensitivity, specificity, positive predictive value, and negative predictive value of lymph node tissue attenuation by using a 99-HU cutoff value were 83%–87%, 93.7%–97.9%, 95.1%–97.3%, and 81.2%–87%. CONCLUSIONS: A combination of 25-second delay CT and 75 mL of iodinated IV contrast can improve the diagnostic accuracy for lateral lymph node metastasis from papillary thyroid carcinoma compared with a combination of a 35- or 70-second delay with 100-mL of iodinated IV contrast.

In patients with isocitrate dehydrogenase wild-type glioblastoma, necrosis of more than 20% was associated with a greater rate of false-positive measurement of 2-hydroxyglutarate with MR spectroscopy. BackgroundIsocitrate dehydrogenase (IDH) mutation has become one of the most important prognostic biomarkers in glioma management. Measurement of 2-hydroxyglutarate (2HG) with MR spectroscopy has shown high pooled sensitivity, although false-positive results with MR spectroscopy have been reported.PurposeTo investigate factors associated with false-positive 2HG measurements at MR spectroscopy in patients with IDH wild-type glioblastoma.Materials and MethodsThis retrospective study was approved by the institutional review board, and informed consent was waived. Consecutive patients with histopathologically confirmed pre- and posttreatment glioblastoma were evaluated between December 2017 and August 2018. Spectroscopy parameters, including 2HG measurements, were obtained with single-voxel point-resolved spectroscopy, and apparent diffusion coefficient (ADC) values were calculated. Necrosis was graded according to the proportion of necrosis within a volume of interest. Poisson regression analyses were perfor...

BACKGROUND AND PURPOSE: The long scan time of MR imaging is a major drawback limiting its clinical use in neuroimaging; therefore, we aimed to investigate the clinical feasibility of a 1-minute full-brain MR imaging using a multicontrast EPI sequence on a different MR imaging scanner than the ones previously reported. MATERIALS AND METHODS: We retrospectively reviewed the records of 146 patients who underwent a multicontrast EPI sequence, including T1-FLAIR, T2-FLAIR, T2WI, DWI, and T2*WI sequences. Two attending neuroradiologists assessed the image quality of each sequence to compare the multicontrast EPI sequence with routine MR imaging protocols. We used the Wilcoxon signed rank test and McNemar test to compare the 2 MR imaging protocols. RESULTS: The multicontrast EPI sequence generally showed sufficient image quality of >2 points using a 4-point assessment scale. Regarding image quality and susceptibility artifacts, there was no significant difference between the multicontrast EPI sequence DWI and routine DWI (P > .05), attesting to noninferiority of the multicontrast EPI, whereas there were significant differences in the other 4 sequences between the 2 MR imaging protocols. CONCLUSIONS: The multicontrast EPI sequence showed sufficient image quality for clinical use with a shorter scan time; however, it was limited by inferior image quality and frequent susceptibility artifacts compared with routine brain MR imaging. Therefore, the multicontrast EPI sequence cannot completely replace the routine MR imaging protocol at present; however, it may be a feasible option in specific clinical situations such as screening, time-critical diseases or for use with patients prone to motion.

Round ligament varicosities are rare, and the mass mimics an inguinal hernia. Round ligament varicosities should be considered in the differential diagnosis of a groin swelling in a female, especially during pregnancy. The diagnosis of round ligament varicosities can be established on grayscale and color Doppler ultrasonography. We report two cases of round ligament varicosities in a 33-year-old non pregnant woman and a 28-year-old pregnant woman, and these patients were diagnosed using ultrasonography. We also reviewed the literature on round ligament varicosities including the present cases. Ultrasonography is diagnostic and can prevent unnecessary surgical intervention and associated morbidity.