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Purpose: To investigate the utility of intravoxel incoherent motion diffusion-weighted MRI (IVIM-DWI) derived diffusion and perfusion parameters in differentiating ocular adnexal lymphoma (OAL) from idiopathic orbital inflammation (IOI), and to assess whether IVIM-DWI provides improved diagnostic performance for the distinction., Method: Twenty-one patients with OAL and 24 patients with IOI underwent IVIM-DWI. Apparent diffusion coefficient (ADC) and IVIM-DWI parameters including true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were measured in lesions by two independent radiologists. The MRI parameter differences between OAL and IOI were tested using two-sample t-test. The receiver operating characteristic (ROC) analysis curves were used to determine the diagnostic performance of significant parameters for differentiation between OAL and IOI., Results: The ADC, D, and f were lower in OAL than those in IOI (ADC = 0.78 ± 0.12 vs. 0.99 ± 0.16 × 10 -3 mm 2 /s, P < 0.001; D = 0.34 ± 0.15 vs. 0.76 ± 0.25 × 10 -3 mm 2 /s, P < 0.001; f = 0.31 ± 0.06 vs. 0.41 ± 0.08 × 100 %, P < 0.001). There was no significant difference in D* between OAL and IOI (P = 0.235). The optimal cut-off values of ADC, D, and f in differentiating OAL from IOI were 0.83 × 10 -3 mm 2 /s, 0.56 × 10 -3 mm 2 /s, and 0.36 × 100 %, respectively. No significant differences were found in areas under the curve (AUCs) among ADC, D and f (all P > 0.05). The combination of D and f provided significantly higher AUC than ADC (AUC = 0.984 vs. 0.838, Z = 2.128, P = 0.033), and had higher sensitivity of 95.24 %, specificity of 95.83 %, and accuracy of 95.56 %., Conclusions: IVIM-DWI is valuable in differentiating OAL from IOI, and D combined f can improve the performance of differential diagnosis., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: Sinonasal angiomatous polyps (SAPs) can be misdiagnosed as malignant tumors due to aggressive clinical behaviors. The purpose of this study was to evaluate the diagnostic accuracy of multiparametric MRI in differentiating SAPs from malignant tumors., Methods: This retrospective study included 31 patients with pathologically proven SAPs and 36 patients with malignant tumors in maxillary sinus and nasal cavity. All the patients underwent conventional MRI and dynamic contrast-enhanced (DCE) MRI on 3T MR scanners. Diffusion-weighted (DW) MR imaging was performed in 45 patients. All the MR images were retrospectively analyzed independently by two authors., Results: Significant differences were found in T1 homogeneity, T2 signal intensity ratio, peripheral hypointense rim on T2WI, and soft tissue infiltration between SAP and malignant tumors (P = 0.004, < 0.001, < 0.001, and = 0.001, respectively). SAPs usually show heterogeneous signal intensity on T1WI, peripheral hypointense rim on T2WI, and higher T2 signal intensity ratio. The tumor size of SAP (4.01 ± 1.08 cm) was slightly smaller than that of malignant tumors (4.56 ± 1.12 cm) (P = 0.045). There were significant differences in DCE-MRI parameters including Tpeak, CImax, WR, TIC types, and progressive enhancement (P = 0.009, < 0.001, = 0.001, = 0.001, and < 0.001, respectively) between SAPs and malignant tumors. All the 31 SAPs showed progressive enhancement on DCE-MRI, while none of the malignant tumors showed progressive enhancement (accuracy 100%). The mean ADC of SAP (1.75 ± 0.30 × 10 -3  mm 2 /s) was higher than that of malignant tumors (1.18 ± 0.31 × 10 -3  mm 2 /s) (P < 0.001)., Conclusion: Multiparametric MRI showed high diagnostic performance in differentiating SAPs from malignant tumors. Progressive enhancement on DCE-MRI is the most effective feature of SAP.

Objective: To investigate the diagnostic value of apparent diffusion coefficient in diffusion weighted imaging at 3.0 T MR for the differentiation in the larcrimal gland tumors. Methods: A total of 73 cases, 36 males and 37 female; mean age 14-81(44±15)years, with lacrimal gland tumors confirmed by pathology in Beijing Tongren Hospital were retrospectively analyzed between January 2011 and April 2016.All cases underwent the preoperative routine MRI and DWI scan, the ADC values were measured in region of interest within the solid zone. The cases were divided into benign and malignant group by the histopathology, according the different pathological categories, the malignant cases were further divided into the epithelial and non-epithelial malignacy. The receiver operating characteristic curve (ROC) was constructed using various cut points of ADC for different parameters to confirm the diagnostic threshold value and evaluate the diagnostic efficacy. Results: There were totally 77 lesions in 73 cases, of which 69 involved unilateral lacrimal gland,4 bilateral lacrimal glands. The mean ADC value of malignant and benign masses in lacrimal gland was (1.36±0.16) and (0.90±0.30)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both( t= -8.319, P< 0.01). The mean ADC value of epithelial and non-epithelial malignacy in lacrimal gland was (1.08±0.18) and (0.54±0.09)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both( t= 11.988, P< 0.01). The area under the ROC for distinguishing malignant from benign lesions was 0.940. Using an ADC value of 1.275×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 94.4%(34/36), specificity of 82.9%(34/41), accuracy of 88.3%(68/77). The area under the ROC for differentiating non-epithelial from epithelial malignacy was 1.0. Using an ADC value of 0.736×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 100%, specificity of 100%, accuracy of 100%. Conclusion: The ADC value is helpful in differentiation among different kinds of tumors in lacrimal masses.

Purpose: To investigate the diagnostic performance of diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), and the combination of both in the differential diagnosis of lymphoma and inflammation in the orbit., Materials and Methods: This retrospective study was approved by the Institutional Review Board and the informed consent requirement was waived. A total of 53 patients underwent preoperative 3T MRI. Parameters of DWI and DCE MRI were evaluated in these 30 patients with orbital lymphoma and 23 patients with orbital inflammation. The diagnostic performance was evaluated using receiver operating characteristic curve analysis., Results: Apparent diffusion coefficient (ADC) values and parameters derived from DCE MRI of orbital lymphoma and orbital inflammation differed significantly (ADC, T max , contrast index [CI], enhancement ratio [ER], and washout ratio [WR]: P < 0.001, P = 0.008, P < 0.001, P < 0.001, and P = 0.005 for reviewer 1, respectively; P < 0.001, P = 0.004, P < 0.001, P < 0.001, and P < 0.001 for reviewer 2, respectively). Sensitivity, specificity, and accuracy values of DWI were 76.67%, 100%, and 86.79% for reviewer 1; 70%, 95.65%, and 81.13% for reviewer 2, respectively. The combination of both were 90%, 86.96%, and 88.68% for reviewer 1; 93.33%, 78.26%, and 86.79% for reviewer 2, respectively. The combination of both was significantly superior to DWI for differentiation of orbital lymphoma from orbital inflammation (P = 0.016 for reviewer 1; P = 0.001 for reviewer 2)., Conclusion: The combination of DWI and DCE MRI can improve diagnostic performance in differentiating lymphoma from inflammation in the orbit compared with DWI alone., Level of Evidence: 3 J. MAGN. RESON. IMAGING 2017;45:1438-1445., (© 2016 International Society for Magnetic Resonance in Medicine.)

Objective: To evaluate the value of dynamic contrast-enhanced MR (DCE-MRI) and diffusion weighted MR (DWI) in differential diagnosis of inflammatory pseudotumor and lymphoma in the lacrimal gland. Methods: In this retrospective study, a total of 24 cases of inflammatory pseudotumor and 22 cases of lymphoma in the lacrimal gland at Beijing Tongren Hospital confirmed by histological results were enrolled from January 2010 to January 2015.DCE-MRI and DWI were performed in these cases, and the type of time-signal intensity curve (time-intensity curve, TIC), the peak contrast index (CIpeak), maximum enhancement ratio (ERmax), washout ratio (WR) and ADC value were analyzed.Differences of these parameters between inflammatory pseudotumor and lymphoma in the lacrimal gland was evaluated by independent samples t test or Mann - Whitney U test.The receiver operating characteristic analysis was used to evaluate the utility of these parameters in discriminating the two diseases. Results: Type of TIC, CIpeak, WR, ERmax and ADC values were statistically different (all P <0.05) between the inflammatory pseudotumor and lymphoma in the lacrimal gland.ERmax, CIpeak and ADC values of inflammatory pseudotumor were greater than those of lymphoma, but the WR values of inflammatory pseudotumor was less than those of lymphoma.The area under the ROC of the CIpeak, WR, ERmax and ADC values was 0.68±0.08, 0.70±0.08, 0.70±0.08, 0.84±0.81 respectively.Using an ADC(b=0, 1000) value of 1.005×10(-3) mm(2)/s as the diagnostic threshold, the sensitivity, specificity and accuracy to differentiate benign lesions from malignant lesions were 84.2%, 65.0% and 75.0% respectively.The diagnostic ability of DWI combined with DCE-MRI was superior to that of DCE-MRI( P =0.000) or DWI alone( P =0.008) with overall sensitivity, specificity and accuracy of 86.3%, 87.5% and 86.9%. Conclusion: DCE-MRI and DWI may improve the diagnostic accuracy in differentiation of the inflammatory pseudotumors and lymphomas in the lacrimal gland, and play an important role in differentiation among them.

Background There are no established biomarkers predictive of the efficacy of treatment for ocular adnexal lymphoma (OAL). Purpose To evaluate the effectiveness of pretreatment dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) in predicting the response of OAL to chemotherapy. Material and Methods Twenty-one patients, who were pathologically diagnosed with OAL, were retrospectively analyzed. According to the National Comprehensive Cancer Network (NCCN) response evaluation criteria for non-Hodgkin's lymphoma, patients were divided into responders (n = 14) and non-responders (n = 7). The volume transfer constant (K trans ), rate constant (K ep ), extracellular extravascular volume fraction (Ve), and apparent diffusion coefficient (ADC) were computed. Two independent-sample tests were applied for statistical analysis. For significantly different parameters, receiver-operator characteristics curve analysis was performed. Results The K trans value (min -1 ), K ep value (min -1 ), and ADC value (10 -3  mm 2 /s) were 0.76 ± 0.36 vs. 0.47 ± 0.18 (mean ± SD), 4.43 ± 1.29 vs. 3.14 ± 1.37, and 0.51 ± 0.12 vs. 0.66 ± 0.15, respectively, in the responders and non-responders groups. Significant differences were found between the two groups regarding these parameters ( P < 0.05). However, no significant difference was observed in Ve (min -1 ) between the groups ( P > 0.05). K trans , K ep , and ADC had a moderately predictive sensitivity or specificity. When K trans and ADC or the three parameters were combined, a considerably higher sensitivity (85.7%) and specificity (85.7%) with a significant discriminative accuracy (area under the curve = 0.929; P = 0.002) was found. Conclusion K trans , K ep , and ADC could potentially predict OAL response to chemotherapy. A combination of these DWI and DCE-MRI quantitative parameters might increase sensitivity and specificity.

Aim: To evaluate the value of 3 T Periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) DUO diffusion-weighted MRI (DW-MRI) in differentiating sinonasal lymphomas from carcinomas., Materials and Methods: PROPELLER DUO DW-MRI was performed in 23 patients with sinonasal lymphomas and 28 patients with carcinomas histologically confirmed at 3 T MRI. Apparent diffusion coefficients (ADCs) were obtained with two different b-values (b = 0 and 700 s/mm(2), b = 0 and 1000 s/mm(2)) and two different regions of interest (ROIs) sampling strategies [whole section (WS), partial section (PS)], respectively. Difference in ADCs between sinonasal lymphomas and carcinomas was evaluated using the independent samples t-test or Mann-Whitney U-test. The utility of ADC thresholds for discriminating between them was evaluated by receiver operating characteristic analysis., Results: ADCs of sinonasal lymphomas (WS ADCb0,700, 0.838 × 10(-3) mm(2)/s) were significantly (p < 0.001) lower than those of carcinomas (WS ADCb0,700, 1.396 × 10(-3) mm(2)/s). Using a WS ADC b0,700 value of 1.040 × 10(-3) mm(2)/s as the threshold value effectively differentiated sinonasal lymphomas from carcinomas with 100% sensitivity, 82.1% specificity, and 82.1% positive and 100% negative predictive values and 90.2% accuracy (b = 0, 700 s/mm(2)). There was no significant difference in diagnostic ability between different b-values settings (p > 0.05) and different sampling strategies of ROIs (p > 0.05), respectively. Additionally, there was significant differences in the ADCs between diffuse large B-cell lymphomas and natural killer (NK)/T-cell lymphomas (p < 0.05)., Conclusion: PROPELLER DUO DW-MRI can effectively differentiate sinonasal lymphomas from carcinomas., (Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Aim: To investigate the role of periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted imaging (DWI) in correcting distortion and evaluating head and neck masses., Materials and Methods: Both PROPELLER and echo planar diffusion weighted imaging (EP-DWI) with different b values were performed using 3 T MRI in 50 patients with solid masses of the head and neck. Distortion severity of 50 masses with both DWI techniques and different b values was qualitatively scored and compared. The apparent diffusion coefficient (ADC) values of the 45 masses, in which the distortion scores with both DWI techniques were ≥2, were measured and calculated. The mean ADC value of each DWI sequence between benign and malignant masses was compared., Results: The mean distortion scores of PROPELLER DWIs were significantly higher than EP-DWIs (3.87 versus 1.96, and 3.88 versus 2.00, with b values of 1000 and 500 s/mm(2), respectively, p < 0.001), indicating distortion of the mass on PROPELLER DWIs was much less than that on EP-DWIs. With either PROPELLER or EP-DWI, the mean ADC value of 24 malignant tumours was significantly lower than that of 21 benign masses (p < 0.001)., Conclusion: Severe distortion of head and neck masses can be reduced significantly using PROPELLER DWI. Moreover, PROPELLER DWI plays an important role in differentiating malignancies from benign masses., (Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Background and Purpose: Prelingual deafness is a hearing loss that occurs before language is acquired and may result in brain structural alterations. We studied microstructural WM alterations in prelingually deaf adolescents by using DTI. We hypothesized that any morphologic alterations are mainly located in the auditory association areas. Furthermore, considering that the developing brain is both more vulnerable to deprivation and more plastic than the adult brain, we speculated that the affected areas should be larger than those previously reported in adult deafness., Materials and Methods: Diffusion tensor images were obtained from 16 prelingually deaf adolescents (age range, 10-18 years) and 16 healthy control adolescents matched for age and sex. Both groups were compared in fractional anisotropy and radial diffusivity by tract-based spatial statistics. In addition, we examined the correlation between the structural data (FA, RD) differences and the duration of sign language use and hearing aid experience., Results: Prelingually deaf adolescents had significantly lower FA and increased RD in the bilateral superior temporal gyri, Heschl gyrus, planum polare, and the splenium of the corpus callosum. Only RD values in the right superior temporal gyrus correlated significantly and negatively (r = -0.518; P = .040) with duration of sign language use. These alterations were larger than those previously reported in adult deafness., Conclusions: As expected, we found severe morphologic changes of decreased FA and increased RD in multiple auditory association areas and in the corpus callosum. These changes are signs of development impairments in prelingually deaf adolescents, possibly reflecting axonal loss or lack of myelination.

Objective: Optic neuritis (ON) is defined as an inflammation of the optic nerve and provides a useful model for studying the effects of inflammatory demyelination of white matter. The aim of this study was to assess the diffusion changes in both the optic nerve and optic radiation in patients with acute and chronic ON using diffusion tensor (DT) MRI., Methods: 33 patients with idiopathic demyelinating optic neuritis (IDON) and 33 gender- and age-matched healthy controls were examined with DT-MRI and with T(1) and T(2) weighted MRI., Results: Compared with controls, both first-episode and recurrent patients with IDON in the acute stage showed significantly increased radial diffusivity (λ(⊥)) and decreased mean fractional anisotropy (FA) in the affected nerves. Reduced FA, increased λ(⊥), mean diffusivity (MD) and axial diffusivity (λ(∥)) were determined in patients with subacute IDON. We found no significant difference in the directional diffusivity of optic radiation in patients whose disease had lasted less than 1 year compared with healthy controls. However, significant changes in the FA and λ(⊥) of the optic radiation were detected in patients with disease duration of more than 1 year., Conclusion: These results show the great potential and capacity of DT-MRI measures as useful biomarkers and indicators for the evaluation of myelin injury in the visual pathway.

The article presents a study which examines the time-dependent changes and provide imaging evidence for diagnosis and therapy in indirect traumatic optic neuropathy (ITON) patients with diffusion tensor imaging (DTI). The differences between injured optic nerve (ON) and contralateral ON as well as the DT magnetic resonance imaging (MRI) were tested on 28 subjects with ITON. Results reveal reduced fractional anisotropy (FA), increased radial and mean diffusivity of injured nerve