Endoscopic ultrasonography for demonstrating loss of multiple-layer pattern of the thickened gallbladder wall in the preoperative diagnosis of gallbladder cancer

The purpose of this study was to elucidate the roles of endoscopic ultrasonography (EUS), conventional US, CT, and MRI in differential diagnosis of gallbladder wall thickening. We scrutinized images for the presence of the multiple-layer patterns of the thickened gallbladder walls during preoperative images (EUS, n = 22; US, n = 23; CT, n = 20; MRI, n = 15) and retrospectively correlated them with surgical results in 25 patients. The pathological diagnoses included 7 gallbladder cancers, 9 cases of chronic cholecystitis, 5 cases of xanthogranulomatous cholecystitis, and 4 cases of adenomyomatosis. Multiple-layer patterns of gallbladder wall were observed in patients with inflammatory and benign diseases by US, EUS, CT, and MRI. This pattern was demonstrated by EUS more efficiently compared with other means of imaging. All subjects with loss of multiple layers were finally diagnosed by use of EUS as having gallbladder cancer at surgery. Loss of multiple-layer patterns of the gallbladder wall demonstrated by EUS was the most specific finding in diagnosing gallbladder cancer. Received 29 July 1996; Revision received 27 November 1996; Accepted 21 January 1997     

子宫内膜良、恶性息肉样病变的MR表现与临床病理对照分析

目的 探讨常规MR及动态增强扫描在子宫内膜息肉样病变中的诊断价值及病理基础.方法 回顾性分析经病理证实的子宫内膜息肉样病变48例,其中恶性肿瘤26例(23例I期子宫内膜癌和3例子宫内膜肉瘤),良性息肉样病变22例(子宫内膜息肉12例和子宫黏膜下肌瘤10例),分析其MR平扫及增强图像病灶特征,并与病理结果 进行对照.采用Fisher精确概率法对纤维核、囊变区及完整结合带在不同子宫内膜息肉样病变中的出现概率进行分析比较.结果 26例子宫内膜恶性息肉病变,其中23例子宫内膜癌在MR T2WI上均表现为子官内膜均匀等或稍高信号肿块(23/23),增强后相对于肌层均呈低信号(23/23),并伴结合带中断或模糊(20/23);子宫内膜含间质成分恶性肿瘤3例,2例为腺肉瘤,1例为癌肉瘤,MR T2WI均为混杂信号,早期局部明显强化,至后期仍明显持续强化;26例子宫内膜恶性息肉病变在MRI上子宫结合带中断或模糊征象出现的概率(23/26)均较子宫内膜息肉(1/11)及子宫黏膜下肌瘤(1/9)高,差异具有统计学意义(P值均<0.05).肿块内小囊变影及不定形纤维核影见于子宫内膜息肉(分别为8/12及5/12),2种征象在子宫内膜息肉中的出现概率均较子宫内膜恶性息肉样病变(3/26及2/26)及子宫黏膜下肌瘤(0及2/10)高,差异具有统计学意义(P值均<0.05);10例子宫黏膜下平滑肌瘤MRI均表现为境界清晰,T2WI呈等或稍低信号肿块,且出现子宫黏膜推移征象(10/10).MR平扫及增强扫描对所有48例子宫内膜息肉样病变的定性诊断敏感度为92.3%(24/26),特异度为83.3%(20/24),准确度为95.8%(46/48).结论 MRI平扫及增强扫描能反映子宫内膜良、恶性息肉样病变的特征,具有很高的诊断价值.     

CT and MR features of xanthogranulomatous cholecystitis: An analysis of consecutive 49 cases

Objective

To study the CT and MR features of xanthogranulomatous cholecystitis (XGC).

Materials and methods

49 patients had pathologically confirmed XGC. All patients underwent contrast enhanced CT, and 10 patients had additional plain MRI. The CT and MRI results were retrospectively analyzed.

Results

On CT, all patients had thickening of gallbladder wall, with 87.8% cases showed diffuse thickening. 85.7% cases had intramural hypo-attenuated nodules in the thickened wall. Continuous mucosal line and luminal surface enhancement were noted in 79.6% and 85.7% cases, respectively. Gallbladder stones were seen in 69.4% patients. The coexistence of the above 5 CT features was seen in 40% cases, and 80% cases had the coexistence of ≥4 features. Diffused gallbladder wall thickening in XGC is more likely to have disrupted mucosal line, and XGC with disrupted mucosal line is more likely to be associated with liver infiltration. In 60% patients the inflammatory process extended beyond gallbladder, with the interface between gallbladder and liver and/or the surrounding fat blurred. 40% cases had an early enhancement of liver parenchyma. Infiltration to other surrounding tissues included bowel (n = 3), stomach (n = 2), and abdominal wall (n = 1). On MR images, 7 of 9 intramural nodules in 7 subjects with T1-weighted dual echo MR images showed higher signal intensity on in-phase images than out-of-phase images.

Conclusion

Coexisting of diffuse gallbladder wall thickening, hypo-attenuated intramural nodules, continuous mucosal line, luminal surface enhancement, and gallbladder stone highly suggest XGC. XGC frequently infiltrate liver and surrounding fat. Chemical-shift MRI helps classifying intramural nodules in the gallbladder wall.     

The value of CT in rectal villous tumors

Computed tomography of 13 patients with villous rectal tumors was reviewed. Five tumors were benign, eight were malignant. All five benign lesions demonstrated homogeneous focal colonic wall thickening of less than 2 cm. Seven of the eight malignant lesions demonstrated focal colonic wall thickening greater than 2 cm. "Fronds," characterized by contrast within the interstices of the lesion, were seen in three malignant lesions. In the remaining five malignant lesions, three had a polypoid appearance, one had low attenuation regions, and one had focal rectal wall thickening. Computed tomography upstaged two carcinomas, downstaged two carcinomas, and accurately staged four carcinomas. Our experience shows (a) CT can demonstrate the classic fronds of villous tumors; (b) benign villous tumors tend to be less than 2 cm and are nonspecific in appearance; (c) biopsy is necessary to differentiate small malignant lesions from benign lesions; and (d) CT is inaccurate in staging local invasion of malignant villous tumors.     

Role of Interface Sign and Diffusion-Weighted Magnetic Resonance Imaging in Differential Diagnosis of Exophytic Renal Masses

PurposeWe aimed to investigate the role of interfaces of exophytic solid and cystic renal masses on magnetic resonance imaging (MRI) and the added value of diffusion-weighted imaging in differentiating benign from malignant lesions.MethodsThe Institutional Review Board approved this retrospective study, and informed consent was waived. A total of 265 patients (109 [41%] women and 156 [59%] men) with a mean age of 57 ± 12 (standard deviation) years were enrolled in this study. Preoperative MRI (n = 238) examinations of patients with solid or cystic renal masses and MRI (n = 27) examinations of patients with Bosniak IIF cysts without progression were reviewed. Solid/cystic pattern, interface types and apparent diffusion coefficient (ADC) values were recorded by 2 radiologists. The diagnostic performance of combining normalized ADC values with interface sign were evaluated.ResultsAmong 265 renal lesions (109 cystic and 156 solid), all malignant lesions (n = 192) had a round interface. No malignant lesions showed an angular interface. For prediction of benignity in cystic lesions, sensitivity (82.86% vs 56.16%), negative predictive value (92.50% vs 85.71%), and accuracy (94.50% vs 87.92%) ratios of angular interface were higher compared to all (solid plus cystic) lesions. The best normalized ADC cutoff values for predicting malignancy in lesions with round interface were as follows: for all (solid plus cystic), ≤ 0.75 (AUROC = 0.804); solid, ≤ 0.6 (AUROC = 0.819); and cystic, ≤ 0.8 (AUROC = 0.936).ConclusionsAngular interface can be a predictor of benignity for especially cystic renal masses. The evaluation of interface type with normalized ADC value can be an important clue in differential diagnosis especially in patients avoiding contrast.     

MR imaging assessment of experimental hepatic dysfunction with mn-DPDP

Manganese (II) N, N'-dipyridoxylethylenediamine-N, N'-diacetate 5,5′-bis(phosphate) (DPDP) is a paramagnetic magnetic resonance (MR) contrast agent that enhances the liver and is predominantly excreted through the biliary tree. The authors evaluated its utility in diffuse liver disease by assessing liver and gallbladder enhancement in 24 rabbits. Total (n = 6) or segmental (n = 6) biliary occlusion or galactosamine-induced hepatitis (n = 6) was induced 3 days before imaging. Six rabbits served as normal controls. T1- and T2-weighted axial MR images were acquired at baseline, followed by T1-weighted images every 10 minutes for 1 hour after the intravenous administration of 20 μmol/kg Mn-DPDP. Except for the segmental occlusion group, the baseline study did not allow distinction between normal and abnormal livers. The temporal hepatic enhancement pattern was statistically different for each group. The normal, segmental occlusion, and hepatitis groups showed patterns similar to one another but markedly higher signal intensity than the total-occlusion group throughout the observation period. In contrast, the gallbladder showed a greater difference in both degree of enhancement and time to peak enhancement among the four groups. Mn-DPDP produces a temporal hepatic enhancement pattern that allows recognition of markedly impaired livers, and gallbladder enhancement patterns that allow distinction of more subtly impaired livers.     

Incidentally discovered adrenal masses: evaluation with Gadolinium enhancement and fat-suppressed MR imaging at 0.5 T

The purpose of the study is to evaluate the ability of Gd-enhancement and fat-suppressed MR imaging operating at midfield strength to characterize incidentally discovered adrenal masses. Sixty patients with 72 adrenal masses incidentally discovered during US or CT exams were studied with a 0.51 MR unit following clinical and laboratory evaluation. After Gd-DTPA intravenous administration a modified three-point Dixon technique was performed in all patients. This technique provided three images sets: conventional T1-weighted SE images, fat-suppressed T1-weighted images and water-suppressed T1-weighted images. Diagnosis was established by means of surgery (11 lesions), fineneedle biopsy (21 lesions) and stability on ultrasonographic follow-up for at least 1 year (range, 12–87 months) from adrenal lesion discovery (40 masses). In most of adenomas (n = 55) an homogeneous enhancement was observed on postcontrast T1WI; however, 15 out of these lesions showed a small focal spot of high intensity in Gd-enhanced fat-suppressed images. On the contrary, malignant conditions (n = 6) and pheochromocytoma (n = 1), all had inhomogeneous signal intensities which were relatively higher after Gadolinium injection as compared with the liver. The fat suppression technique demonstrated areas of bright signal intensity related to high vascularity. The performance of three observers in order to differentiate malignant from benign conditions showed sensitivity, specificity, diagnostic accuracy, positive and negative predictive values of 100, 88.5, 90, 50 and 100% on the basis of gadolinium enhancement only, by utilizing the Dixon technique. In conclusion, although Gd-enhancement and fat-suppressed sequence helped correctly differentiate among the groups of incidentally discovered adrenal masses, the degree of overlap suggests that it is still difficult to characterize individual patients. However, the modified three-point Dixon technique after contrast material administration appears to be a further capability of midfield MRI in the characterization of adrenal tissue.     

0.5 T MRI of small renal masses: value of T2-weighted and Gd-DOTA-enhanced images

We compared the value of T2-weighted and Gd-DOTA-enhanced T1-weighted images for the detection and characterisation of 33 small renal masses (14 clear cell carcinomas, 6 angiomyolipomas, 3 angiomyomas, 4 adenomas, 3 papillary carcinomas, 3 oncocytomas, 1 haemorrhagic cyst). Dynamic enhanced MRI was performed to study the tumoral vascular supply (19 cases). MRI depicted all the masses more than 1 cm in diameter, but missed all the lesions less than 1 cm (4 false-negative). The results of T2-weighted images and Gd-DOTA-enhanced images were similar as regards detection; however, Gd-DOTA-enhanced images depicted more clearly the tumours smaller than 2 cm (11 cases). MRI enabled the characterisation of only 3 masses (2 angiomyolipomas, 1 haemorrhagic cyst). New MRI features are described for oncocytomas (low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, early and marked enhancement on dynamic enhanced MRI). Dynamic enhanced MRI did not contribute to the differentiation of benign from malignant tumours. Correspondence to: O. Hélénon     

MR diffusion imaging and ADC measurement in solid and cystic mediastinal masses for differentiating benign from malignant lesions

Purpose

The purpose of this study is to evaluate the role of MR diffusion imaging (DWI) and apparent diffusion coefficient (ADC) measurement of solid and cystic mediastinal masses to differentiate benign from malignant lesions.

Application of a quantitative model to differentiate benign from malignant breast lesions detected by dynamic,gadolinium-enhanced MRI

Both benign and malignant breast lesions may exhibit intense contrast enhancement when imaged using gadolinium-enhanced MRI. We propose a quantitative approach for fitting dynamic signal intensity (SI) data that may distinguish benign from malignant lesions. We studied 78 lesions in 75 women (18 malignancies, 16 fibroadenomas, and 44 other benign breast lesions) to determine the potential of this model for decreasing false-positive MR results. Twenty-eight lesions showed no enhancement; all were benign. One lesion showed a complex pattern not amenable to region-of-interest analysis and was considered a false positive. SI versus time data for the remaining 49 lesions were fit to the proposed model. We found that one parameter, M, the normalized slope of the SI enhancement profile evaluated at half the maximal signal intensity, seemed to be highly correlated with malignancy and offered improved discrimination between malignant and benign lesions compared to a previously published two-point slope method.     

胆囊癌的CT诊断及鉴别诊断(附33例报道)

目的:探讨胆囊癌的CT表现及鉴别诊断.方法:33例经手术病理证实的胆囊癌,对其CT表现进行观察分析.结果:胆囊癌以老年女性多见,临床表现为黄疸及腹部肿块、纳差.CT表现:胆囊区肿块,密度不均,胆囊腔缩小或消失;胆囊壁增厚,呈局限性或弥漫性不规则增厚;胆囊腔内软组织块影;合并胆结石;肝内外胆管扩张;肝脏直接受侵范;肝脏转移,侵犯腹壁,合并腹水.增强扫描可见病灶中度及明显强化.病灶周围及邻近器官侵犯、淋巴结转移更有助于诊断.结论:仔细观察胆囊及其周围结构、邻近器官改变,旨在提高胆囊癌的诊断正确率.     

Role of MR spectroscopy and diffusion-weighted imaging in diagnosis of orbital masses

Purpose

To assess the value of (MRI), (DWI) and (MRS) in the diagnosis of different orbital masses and differentiation between benign and malignant masses.

Are growth patterns on MRI in small (&lt; 4 cm) solid renal masses useful for predicting benign histology?

Purpose

To evaluate previously described growth patterns in < 4 cm solid renal masses.

Materials and Methods

With IRB approval, 63 renal cell carcinomas (RCC; clear cell n = 22, papillary n = 28, chromophobe n = 13) and 36 benign masses [minimal-fat (mf) angiomyolipoma (AML) n = 13, oncocytoma n = 23) from a single institution were independently evaluated by two blinded radiologists (R1/R2) using T2-weighted MRI for (1) the angular interface sign (AIS), (2) bubble-over sign (BOS), (3) percentage (%) exophytic growth and (4) long-to-short axis ratio. Comparisons were performed using ANOVA, chi-square and multi-variate regression.

Results

AIS was present in 11.1% (7/63) -9.5% (6/63) R1/R2 RCC compared to 13.9% (5/36) -19.4% (7/36) R1/R2 benign masses (p = 0.68 and 0.16). BOS was present in 11.1% (7/63) -3.2% (2/63) R1/R2 RCC compared to 16.7% (6/36) -8.3% (3/36) R1/R2 benign masses (p = 0.432 and 0.261). Agreement was moderate (K = 0.50 and 0.55). mf-AML [66 ± 32% (range 0-100%)] and oncocytoma [53 ± 26% (0-90%)] had larger % exophytic growth compared to RCC [32 ± 23% (0-80%)] (p < 0.001). No RCC had 90-100% exophytic growth, present in 38.5% (5/13) mf-AMLs and 17.4% (4/23) oncocytomas. The long-to-short axis did not differ between groups (p = 0.053).

Conclusions

Benign masses show greater % exophytic growth whereas other growth patterns are not useful. Future studies evaluating % exophytic growth using multi-variate MR analysis in renal masses are required.

Key Points

? Greater exophytic growth is associated with benignity among solid renal masses. ? Only minimal fat AMLs and oncocytomas had 90-100% exophytic growth. ? The angular interface sign was not useful to differentiate benign masses from RCC. ? The bubble-over sign was not useful to differentiate benign masses from RCC. ? Subjective analysis of growth patterns had fair-to-moderate agreement.

     

Nasopharyngeal tuberculosis: CT and MRI findings in thirty-six patients

Purpose

Tuberculosis is uncommon in the nasopharynx. The purpose of this study was to investigate the CT and MRI features of 36 cases of tuberculosis in this area.

Materials and methods

CT (n = 15) and MRI (n = 21) scans from 36 patients with histologically proved tuberculosis of the nasopharynx were reviewed by two experienced radiologists, paying particular attention to the lesions’ distribution, location, extent, size, internal architecture, pattern, and degree of enhancement, and cervical lymphadenopathy.

Results

Twenty-nine patients exhibited a polypoid mass pattern and seven had diffuse mucosal thickening. The roof of the nasopharynx was involved in all cases. The mean size of the lesions was 11.4 mm. Striped pattern was detected in 19 cases. Adjacent muscle invasion or bone destruction was not detected. Heterogeneous enhancement was detected in all patients, and necrosis in the nasopharyngeal lesions was detected in 16 cases. Poor, moderate, and marked enhancement was detected in one, 27, and eight cases, respectively. Thirty-four patients had involvement of the cervical lymph nodes. Twenty-two and 28 cases were associated with bilateral lymphadenopathy or necrosis, respectively. The retropharyngeal lymph node was the most commonly involved site (94.1%).

Conclusion

The presence of necrosis and striped pattern in nasopharyngeal lesions, site predilection, no invasion of regional structures, and central necrosis with peripheral rim enhancement of cervical lymphadenopathy may suggest the diagnosis of nasopharyngeal tuberculosis.     

女性盆腔肿块的MRI诊断与鉴别诊断

目的:探讨MRI在女性盆腔肿块中的诊断与鉴别诊断价值。方法:回顾性分析139个(75例)经术后病理证实的盆腔肿块的MRI征象。结果:MRI检出病灶共129个(129/139,92.8%),其中子宫病变67个(67/69,97.1%),卵巢病变62个(62/70,88.6%),2个子宫肌瘤、5个卵巢冠囊肿、3个黄体囊肿漏诊(10/139,7.2%)。MRI检出的129个病灶中,128个病灶部位均符合手术所见,准确性为99.2%。子宫病变主要表现为实质性肿块影或子宫内膜增厚;卵巢病变表现为囊性、囊实性或实性肿块影。MRI诊断为良性病变108个,恶性病变21个;病理诊断为良性病变116个,恶性病变23个,MRI诊断出恶性病变的灵敏度为91.3%(21/23),阳性预测值为100%。结论:MRI判断盆腔病灶的起源具有很高的准确性,在判断良恶性肿瘤方面亦具有较高的准确性,但是区分恶性肿瘤的细胞类型难度较大。     

Improved diagnostic accuracy of breast MRI through combined apparent diffusion coefficients and dynamic contrast‐enhanced kinetics

This study investigated the relationship between apparent diffusion coefficient (ADC) measures and dynamic contrast‐enhanced magnetic resonance imaging (MRI) kinetics in breast lesions and evaluated the relative diagnostic value of each quantitative parameter. Seventy‐seven women with 100 breast lesions (27 malignant and 73 benign) underwent both dynamic contrast‐enhanced MRI and diffusion weighted MRI. Dynamic contrast‐enhanced MRI kinetic parameters included peak initial enhancement, predominant delayed kinetic curve type (persistent, plateau, or washout), and worst delayed kinetic curve type (washout > plateau > persistent). Associations between ADC and dynamic contrast‐enhanced MRI kinetic parameters and predictions of malignancy were evaluated. Results showed that ADC was significantly associated with predominant curve type (ADC was higher for lesions exhibiting predominantly persistent enhancement compared with those exhibiting predominantly washout or plateau, P = 0.006), but was not significantly associated with peak initial enhancement or worst curve type (P > 0.05). Univariate analysis showed significant differences between benign and malignant lesions in both ADC (P < 0.001) and worst curve (P = 0.003). In multivariate analysis, worst curve type and ADC were significant independent predictors of benign versus malignant outcome and in combination produced the highest area under the receiver operating characteristic curve (0.85 and 0.78 with 5‐fold cross validation). Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.     

Fibroadenomas of the breast: histopathological/dynamic contrast-enhanced MR correlation

A total of 22 women with fibroadenomas had preoperative dynamic MR study (T1-weighted images every 47 s after injection of Gd-DOTA). Their age, hormonal status, breast MR studies and histopathological slides were retrospectively reviewed. Eleven pre- (n = 2) or post-menopausal (n = 9) women showed no early contrast enhancement. The absence of early contrast enhancement correlated with hyalin stromal component. Eleven pre- (n = 7) or post-menopausal (n = 4) women showed focal (n = 9) or diffuse (n = 2) early contrast enhancement. Early focal contrast enhancement correlated with myxoid (n = 9), mixed hyalin/myxoid (n = 1) or hyalin (n = 1) fibroadenomas. Early diffuse contrast enhancement of the breast correlated with myxoid (n = 1) or hyalin (n = 1) stromal component associated with proliferative fibrocystic disease of the breast parenchyma. The presence of contrast enhancement correlated with myxoid fibroadenomas, whereas absence of contrast enhancement correlated with hyalin fibroadenomas. As hyalin fibroadenomas occurs in post-menopausal women, the diagnostic accuracy of dynamic MRI may be improved in this age group. Correspondence to: R. Gilles     

Apparent diffusion coefficient measurements in the differentiation between benign and malignant neck masses

Aim

Evaluate the role of ADC value measurements in the differentiation between benign and malignant neck masses.

Methods

From April 2011 to February 2013, prospective study was conducted on 30 patients (17 male and 13 female), with the mean age 43.3 ± 6 years. Collected from wards and clinics of General Surgery and Otolaryngology Departments complaining from neck masses. MRI, Diffusion-Weighted Imaging (b value 0, 100, 500 and 1000 s/mm) and ADC value calculation were performed and the results were correlated with histopathological results and/or follow up.

Results

The present study include 30 patients (Lymphadenopathy {(n = 15) (11 as single entity), (4 associated with other entities)}, Focal thyroid swelling (n = 5), Salivary gland masses (n = 3) {Parotitis (1 case), Parotid carcinoma (2 cases)}, Nasopharyngeal masses (n = 5), Oropharyngeal masses (n = 2), Ludwig angina (n = 2) and Laryngeal masses (n = 2).The mean ADC of the malignant neck masses was (0.699 + 0.267 × 10^-3 mm²/s) while that of the benign masses was (1.879 + 0.751 × 10^-3 mm²/s).The results confirmed by biopsy in 23 cases and follow up (7 cases).The sensitivity, specificity, PPV, NPV and overall accuracy of quantitative diffusion WI in differentiating benign from malignant neck masses were 95.4%, 83.3%, 95.4%, 83%, and 92%.

Conclusion

ADC value calculation are promising noninvasive imaging approach that can be used in distinguishing between benign and malignant neck masses. Benign lesions have higher mean ADC values than malignant lesions, the cutoff value was 1.25 × 10^-3 mm²/s while 0.8 × 10^-3 mm²/s in thyroid lesions.     

Tumors of peripheral nerves: correlation of symptoms, clinical signs, imaging features, and histologic diagnosis

Objective. To distinguish between benign and malignant tumors in the peripheral nerves. Design and patients. The clinical, imaging and histologic findings of 99 benign and 16 malignant tumors in the peripheral nerves were reviewed retrospectively. Results. Preoperative motor weakness was observed in only six of 99 benign tumors and was mild, while slight to severe motor weakness was present in 15 of 16 malignant lesions. Pain at rest was present in five of 99 benign tumors and in 15 of 16 malignant tumors. All benign lesions showed a smooth tumoral margin, while half the malignant lesions showed an invasive margin on CT or MRI. Thirteen of 28 benign lesions on CT and nine of 23 on MRI showed round to geographic central enhancement, but this pattern was not seen in malignant lesions. Conclusion. Absence of severe motor weakness and a central enhancement pattern strongly suggest a benign nature, while severe rest pain and invasive tumor margin suggest malignant lesions in peripheral nerve tumors. Received: 30 July 1998 Revision requested: 30 October 1998 Revision received: 30 November 1998 Accepted: 12 January 1999     

Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging for Differentiation Between Parotid Neoplasms

PurposeThis study was designed to evaluate the role of multiparametric magnetic resonance imaging (MRI) for differentiation of parotid gland neoplasms.MethodsProspective study was conducted upon 52 consecutive patients (30 men, 22 women; aged 24–78 years; mean, 51 years) with parotid tumours that underwent multiparametric MRI using combined static MRI, dynamic contrast enhanced (DCE) MRI, and diffusion-weighted imaging (DWI). The static MRI parameter, time signal intensity curves (TIC) derived from DCE-MRI, and apparent diffusion coefficient (ADC) values of parotid tumours were correlated with histopathological findings.ResultsStatic MRI revealed a significant difference between both benign and malignant lesions in regards to margin definition (P < .001) and T2 hypointensity (P < .013), with a diagnostic accuracy 95% and 78.33% respectively. Study of the TIC type on DCE-MRI revealed statistically significant difference between benign and malignant lesions (P < .001) and diagnostic accuracy 96.55%. There was no statistically significant difference (P = .181) between the ADC values of benign and malignant lesions. ROC curve analysis revealed that by using ADC cut-off value of 1 × 10^?3 mm²/s had accuracy of 84.62% respectively for differentiating Warthin from malignant tumours that could be modified to higher value (94.28%) by excluding lymphoma from malignant lesions. By using cutoff value of 1.3 × 10^?3 mm²/s to differentiate pleomorphic adenoma from malignancy, ROC curve analysis had high accuracy of 97.06%.ConclusionMultiparametric MRI can be used for differentiation of malignant from benign parotid tumours and characterization of some benign parotid tumours.