Reliability and Validity of Different MRI Sequences in Improving the Accuracy of Differential Diagnosis of Benign and Malignant Vertebral Fractures: A Meta-Analysis.

OBJECTIVE. We aimed to systematically examine the reliability and validity of different MRI sequences in differentiating benign and malignant vertebral fractures, appropriately select the best MRI sequence to improve the diagnostic accuracy, and compare the diagnostic accuracy of MRI sequences in the context of different study designs or publication date. MATERIALS AND METHODS. Computer and manual retrieval were conducted on studies published between January 1, 2000, and September 31, 2016. Studies relevant to the differential diagnosis of benign and malignant vertebral fractures by MRI and reference standard (histopathologic diagnosis or clinical follow-up examination) were analyzed. RESULTS. Eighteen articles were included. Neither threshold (p = 0.86) nor nonthreshold (p = 0.06) effects were present. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 89% (95% CI, 86-92%), 88% (95% CI, 85-91%), 6.54 (95% CI, 4.44-9.65), 0.14 (95% CI, 0.09-0.21), and 55.76 (95% CI, 37.06-83.89), respectively. The AUC was 0.95. The risk of publication bias was negligible (p = 0.33). CONCLUSION. MRI sequences could provide appreciable diagnostic performance in differentiating benign and malignant vertebral fractures. However, our pooled estimates do not support the superiority of one set of sequences over another, and there is not sufficient evidence to show that prospective or recent studies are obviously better than retrospective or older studies.

A pilot evaluation of magnetic resonance imaging characteristics seen with solid papillary carcinomas of the breast in 4 patients.

BACKGROUND: Solid papillary carcinoma (SPC) is a rare variant of breast papillary carcinoma with unique pathological morphology and biological behavior. There is only one case report on T1-MRI of SPC. In this study, we report our findings on this new category of papillary carcinoma to fill the gap in MRI characterization of SPC. METHODS: This retrospective study included four pathology-confirmed in situ SPC patients. Conventional MRI, diffusion weighted imaging (DWI), and magnetic resonance spectroscopy (MRS) were performed with a 1.5 T whole-body MR scanner before surgical operation. The following characteristics of each lesion were recorded: signal intensity on T2WI/STIR and T1FSPGR, morphology, maximum lesion size, and time intensity curve (TIC) on dynamic contrast enhancement MRI (DCE-MRI), apparent diffusion coefficient (ADC) value from DWI, and Cho peak from MRS. RESULTS: Signal intensities of all lesions were heterogenous on T2WI/STIR and T1FSPGR. Mass enhancements were observed for all lesions with either oval or irregular shapes on DCE-MRI. The maximum lesion size ranged from 0.8 cm to 3.2 cm. All lesion margins were circumscribed, and internal enhancements were homogeneous or heterogeneous from DCE-MRI. TIC appeared with a rapid increase in initial contrast phases of all lesions. All lesions on DWI (b = 1000s/mm2) were slightly hyperintense with an ADC value range of 1.3 × 10-3 mm2/s to 1.9 × 10-3 mm2/s. Cho peak was absent at 3.2 ppm for all lesions. CONCLUSIONS: MRI characteristics of SPC include heterogeneous signal intensity within the lesion on T2WI/STIR and T1FSPGR, mass enhancement with circumscribed margins, either oval or irregular shapes, and a rapid initial enhancement of TIC on DCE-MRI. ADC values and the absence of Cho peak may provide valuable information to distinguish SPC from other invasive breast carcinomas.

Correlation of putative iron content as represented by changes in R2* and phase with age in deep gray matter of healthy adults.

PURPOSE: To establish a correlation between putative iron content using susceptibility weighted imaging (SWI) phase and T2* weighted magnitude values in the basal ganglia and the thalamus as a function of age in healthy human brains. MATERIALS AND METHODS: One hundred healthy adults (range, 20-69 years; mean, 43 years) were evaluated for this study using a gradient echo sequence. The original magnitude and high pass filtered phase data were analyzed as proxy variables for iron content in the substantia nigra, red nucleus, globus pallidus, putamen, caudate nucleus, thalamus, and pulvinar thalamus. Each structure was broken into two parts, a high iron content region and a low iron content region. RESULTS: Both magnitude and phase data showed an increase in putative iron content with age. However, the high iron content region revealed two new pieces of information: both the average iron content per pixel and the area of high iron increased with age. Furthermore, significant increase in iron uptake as a function of age was found past the age of 40. CONCLUSION: A two region of interest analysis of iron is a much more sensitive means to evaluate iron content change over time. Contrary to the current belief that iron content increases level off with age, the putative iron deposition in the high iron content region is seen to increase with age.

Intravoxel Incoherent Motion MR Imaging: Comparison of Diffusion and Perfusion Characteristics for Differential Diagnosis of Soft Tissue Tumors.

We used intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) to explore the possibility of preoperative diagnosis of soft tissue tumors (STTs). This prospective study enrolled 23 patients. Conventional MRI and IVIM examinations were performed on a 3.0T MR imager. Eight (35%) hemangiomas, 11 (47%) benign soft tissue tumors excluding hemangiomas (BSTTEHs) and 4 soft tissue sarcomas (STSs) were assessed. The mean tumor size was about 1652.36 ±â€Š233.66  mm(2). Ten b values (0-800  s/mm(2)) were used to evaluate diffusion and perfusion characteristics of IVIM. IVIM parameters (ADC(standard), ADC(slow), ADC(fast), and f) of STTs were measured and evaluated for differentiating hemangiomas, BSTTEHs, and STSs. ADC(slow) and ADC(fast) value were different for hemangiomas, BSTTEHs, and STSs separately (P < 0.001, P < 0.001, and P = 0.001). ADC(slow), cut-off value smaller than 0.93 × 10(-3)  mm(2)/s, was the best parameter to differ STSs (0.689 ±â€Š0.173 × 10 (-3)mm(2)/s) from hemangiomas (0.933 ±â€Š0.237 × 10 (-3)mm(2)/s) and BSTTEHs (1.156 ±â€Š0.120 × 10 (-3)mm(2)/s) (P = 0.001). ADC(slow) (0.93 × 10(-3)  mm(2)/s

[Comparison of gradient echo and echo planar imaging measurements for the calculation of regional blood volume maps]. / Bestimmung des regionalen Blutvolumens (rBV) in Meningeomen: Vergleich von Echoplanar- und Gradientenechosequenzen.

The purpose of this study was to evaluate relative regional blood volume (rCBV) in meningioma and compare the utility of reconstruction using both gradient-echo sequence and echo-planar-imaging (EPI) sequence. Eighteen patients with meningiomas were studied on a Siemens 1.5-T scanner. During the gradient-echo sequence (n=12) and EPI sequence (n=6), a bolus (0.2 mmol/kg) of Gd-DTPA was injected mechanically with a flow rate of 5 ml/second. Image processing of dynamic data was performed on a pixel-by-pixel basis. The ratio of tumor rCBV/gray matter rCBV was 3.01 +/- 1.18 (3.07 +/- 1.39 in gradient sequence and 2.84 +/- 0.94 in EPI sequence). The ratio of gray matter/white matter as the reference tissue had a mean of 2.79 +/- 0.76 using the FLASH sequence, and a mean of 3.04 +/- 1.31 using EPI. These differences were not statistically signifcant (P>0.5, t-test). According to the ratio of tumor rCBV/gray matter rCBV, a mean value, 14.5 ml/100 g, of rCBV in meningiomas was calculated. Compared with gray matter, increased inhomogeneous rCBV was observed in meningioma. Based on the two different sequences, no bias can be observed in our rCBV reconstruction.

Langerhans cell histiocytosis of the clavicle: a case report and review of the literature.

We report a rare case of solitary Langerhans cell histiocytosis (LCH) involving the clavicle of an adult female. The patient was a 32-year-old female presenting with 1 month history of progressive pain, swelling, and tenderness in the region near the left sternoclavicular joint. Radiograph, computed tomography, and magnetic resonance imaging showed an osteolytic lesion in the clavicle with tumor extension and soft tissue edema. Surgical curettage of the lesion was performed, and the histopathologic diagnosis was LCH. Because of its rarity and possibly variable presentation, LCH should be included and considered in the differential diagnosis when we encounter a clavicle lesion.