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Objectives: To explore the ability of conventional MRI and histogram analysis of apparent diffusion coefficient (ADC) for differentiating between malignant and benign palatal lesions., Materials and Methods: A retrospective analysis was performed on MRI images of 86 patients with palatal lesions confirmed by histopathology between January 2015 and December 2018. Each lesion was evaluated based on the conventional MRI characteristics, including size, location, morphology, inner texture, enhancement, capsule, bone destruction, and nerve invasion. ADC histogram analysis was fitted to a bimodal Gaussian distribution mixture curve. Nine histogram analysis parameters were extracted from ADC maps and were compared between malignant and benign palatal lesions. Statistical analysis was performed to assess the differential performance of each parameter individually and combined., Results: On conventional MRI, the capsule structure and nerve invasion were useful characteristics for the differential diagnosis of palatal lesions. Histogram analysis showed significant differences between the groups in terms of mean ADC values of the lower curve and overall curve of the bimodal histogram, as well as ADC 10 and ADC 50 . The optimal diagnostic threshold of ADC value was ADC 50  = 1.17 × 10 -3 mm 2 /s (area under curve [AUC] = 0.934, sensitivity = 93.0 %, specificity = 86.2 %). The combination of conventional MRI and ADC values yielded the best predictive performance, with an AUC of 0.949, and an increase in sensitivity from 80.7 % to 96.5 % and specificity from 58.6 % to 82.8 %, compared to conventional MRI., Conclusions: Histogram analysis of DWI combined with conventional MRI allows accurate differentiation between benign and malignant palatal lesions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Bell's palsy (BP) is the most common form of acute facial nerve disorder and is characterized by rapid onset peripheral facial palsy of unknown etiology., Purpose: To explore the diagnostic value of dynamic contrast-enhanced (DCE) magnetic resonance imagine (MRI) in patients with BP particularly in involved segments., Material and Methods: A retrospective analysis was performed on the patients with BP who underwent routine MRI examinations and volumetric interpolated breath-hold examination (VIBE) sequence-based DCE-MRI before surgery in our department from January 2015 to July 2020. DCE-MRI data postprocessing was performed on Siemens Workstation Extended MR Work Space 2.6.3.5. Statistical analyses were performed using SPSS®v.19.0. The inter-observer reliability was evaluated with kappa identity test and McNemar's test., Results: Twenty-three patients were included. On conventional contrast-enhanced MRI, the two observers were inconsistent in their diagnosis of lesion segments of facial nerve (Kappa 0.426, P  = 0.009). Compared to the results of the surgery, the diagnostic consistency of both observers was general (Kappa 0.476, P  < 0.001 and Kappa 0.430, P  < 0.001, respectively). The diagnostic results of DCE-MRI for lesion segments of the facial nerve were consistent between the two observers (Kappa 0.929, P  < 0.001). Compared to the results of the surgery, the diagnostic consistency of both observers was good (Kappa 0.753, P  < 0.001 and Kappa 0.731, P  < 0.001, respectively)., Conclusion: Compared to conventional MRI, DCE-MRI has good stability and repeatability in the diagnosis of the lesion segments of the facial nerve as well as a good specificity and accuracy.

Objective: To investigate the therapeutic efficacy of Iodine-125 ( 125 I) seeds brachytherapy to pancreatic ductal adenocarcinoma (PDAC) xenografts via multiparametric magnetic resonance imaging (MRI) analysis., Materials and Methods: Twenty mice were implanted subcutaneously with SW-1990 PDAC xenografts. The tumor-bearing mice were randomly divided into 125 I seeds group (n = 10) and blank control group (n = 10). Treatment response was monitored by diffusion-weighted magnetic resonance imaging (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI) obtained 1 day before, 14 and 60 days after treatment. Imaging results were correlated with histopathology., Results: 125 I seeds brachytherapy resulted in a significant increase in mean tumor apparent diffusion coefficient (ADC) values compared to the control at 14 and 60 days after treatment (p < 0.05). DCE-MRI showed a significant decrease in the perfusion parameters including K trans and K ep (p < 0.05). The mean ADCs within the peripheral region of the tumors were linearly proportional to the mean apoptotic cell density (p = 0.015; Spearman's coefficient = 0.945). The K trans and K ep were linearly proportional to microvessel density (MVD) (p = 0.043, 0.047; Spearman's coefficient = 0.891, 0.884)., Conclusion: 125 I seeds brachytherapy leads to effective inhibition of PDAC cell proliferation, higher degree of necrosis and necroptosis, and lower MVD. Both DW-MRI and DCE-MRI are feasible to monitor a response to 125 I seeds brachytherapy in the PDAC xenografts. This paper shows an original project concerning about a possible palliative treatment not only in a murine model (preclinical setting) but also in humans.

Objective: To evaluate and compare the ability of conventional MRI, diffusion-weighted imaging (DWI) and a combination of both MRI techniques to differentiate malignant and benign palatal lesions., Methods: A retrospective review of MRI findings was performed in patients with pathologically confirmed palatal lesions between January 2012 and December 2014. Each lesion was evaluated with conventional MRI characteristics, including enhancement, inner texture, margin, adjacent soft-tissue involvement and cervical lymph node, and/or apparent diffusion coefficient (ADC) value. Statistical analyses were performed to assess the differential performance of each parameter separately and together., Results: A total of 42 patients (24 males, 18 females; age: 54.9 ± 16.4 years) were investigated. The optimal cut-off ADC value to distinguish malignant from benign lesions was 1.02 × 10(-3) mm(2) s(-1), with a sensitivity of 87.5% and a specificity of 75.0%. Conventional MRI showed a sensitivity of 87.1% and a specificity of 63.6%. Combination of conventional MRI and ADC scores increased sensitivity to 100% and specificity to 75.0%. The AUCs did not differ significantly between conventional MRI alone, DWI alone and integration of both., Conclusion: Additional DWI does not substantially improve differential ability of conventional MRI. However, combining ADC values with conventional MRI improves both sensitivity and specificity, which is of worth to be further validated in prospective studies with larger sample sizes., Advances in Knowledge: Combination of conventional MRI and ADC scores could increase the ability to differentiate malignant from benign palatal lesions, with a sensitivity of 100% and specificity of 75.0%, although without statistical significance.

Objective: To evaluate the ability of conventional MRI, diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI to differentiate malignant and benign parotid lesions., Methods: A retrospective review of MRI findings was performed in patients with pathologically confirmed parotid lesions between January 2010 and December 2014. Morphological MRI characteristics and functional characteristics such as apparent diffusion coefficient (ADC) and pattern of time-signal intensity curve (TIC) were recorded and compared. For each lesion, summed scores were respectively calculated for conventional MRI alone, conventional MRI with DWI and/or with DCE-MRI. Statistical analyses were performed to assess the association of these characteristics and summed scores with malignancy., Results: A total of 207 patients (111 males and 96 females; age: 48.4 ± 17.0 years) were included, consisting of 156 benign and 51 malignant tumours. After adjusting for age, sex, smoking status, alcohol use and tumour size, the lesions with ill-defined margin, adjacent tissue infiltration, cervical lymphadenopathy, ADC ≤1.01 × 10(-3) mm(2) s(-1) and plateau TIC pattern are more likely to be malignant than those without these findings. Significant difference in receiver operator characteristic was detected after adding DWI to conventional MRI (p = 0.003), generating a sensitivity and specificity of 54.05% and 91.30%, respectively. Compared with lesions score <3, lesions with score ≥5 in the combination of conventional MRI and DWI were approximately 90 times more likely to be malignant parotid tumour. Additional DCE-MRI did not improve differential ability of conventional MRI., Conclusion: Morphological and functional MRI characteristics are associated with malignancy in parotid gland. The diagnostic value of MRI would increase when DWI is applied in combination with conventional MRI., Advances in Knowledge: The parotid lesions with ill-defined margin, adjacent tissue infiltration, cervical lymphadenopathy, ADC ≤1.01 × 10(-3) mm(2) s(-1) and plateau TIC pattern are more likely to be malignant. The diagnostic value of conventional MRI would be increased when DWI is applied in combination, whereas additional DCE-MRI did not improve differential ability of conventional MRI.

Objectives: To compare the correlation of depth of invasion (DOI) measured on multiple magnetic resonance imaging (MRI) sequences and pathological DOI, in order to determine the optimal MRI sequence for measurement. Methods: A total of 122 oral tongue squamous cell carcinoma (OTSCC) patients were retrospectively analyzed, who had received preoperative MRI and surgical resection. DOIs measured on fat-suppressed T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), dynamic enhanced-T1 high-resolution insotropic volume examination (e-THRIVE), and contrast-enhanced fat-suppressed T1WI (CE-T1WI) were respectively compared to those measured in pathologic specimens. The cutoff value of the best correlated MRI sequence was determined, and the T staging accuracy of MRI-derived DOI was evaluated. Results: DOI derived from e-THRIVE showed the best correlation (r = 0.936, p < 0.001) with pathological DOI. The area under the curve values of MRI-derived DOI distinguishing T1 stage from T2 stage and distinguishing T2 stage from T3 stage were 0.969 and 0.974, respectively. The T staging criteria of MRI-derived DOI were 6.2 mm and 11.4 mm, with a staging accuracy of 86.9% compared to pathological DOI criteria of 5 mm and 10 mm. Conclusion: E-THRIVE was the optimal MR sequence to measure the MR-derived DOI, and DOI derived from e-THRIVE could serve as a potential cut-off value as a clinical T staging indicator of OTSCC. Key Points: • Multiparametric MRI helps radiologists to assess the neoplasm invasion in patients with oral tongue squamous cell carcinoma. • Retrospective study indicated that measurement was most accurate on enhanced-T1 high-resolution insotropic volume examination dynamic contrast enhancement images. • T staging of oral tongue squamous cell carcinoma was accurate according to the dynamic contrast enhancement MRI-derived depth of invasion. [ABSTRACT FROM AUTHOR]