Visceral to subcutaneous fat ratio predicts short-term mortality in patients with Covid 19. A multicenter study.

OBJECTIVE: To evaluate the association of body composition parameters with outcomes in Covid-19. METHODS: 173 patients hospitalized for Covid-19 infection in 6 European centers were included in this retrospective study. Measurements were performed at L3-level and comprised skeletal muscle index (SMI), muscle density (MD), and adipose tissue measurements [visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), intramuscular adipose tissue (IMAT), visceral-to-subcutaneous-adipose-tissue-area-ratio (VSR)]. The association with mortality, the need for intubation (MV), and the need for admission to ICU within 30 days were evaluated. RESULTS: Higher SAT density was associated with a greater risk of MV (OR = 1.071, 95%CI=(1.034;1.110), p < 0.001). Higher VAT density was associated with admission to ICU (OR = 1.068, 95%CI=(1.029;1.109), p < 0.001). Higher MD was a protective factor for MV and ICU admission (OR = 0.914, 95%CI=(0.870;0.960), p < 0.001; OR = 0.882, 95%CI=(0.832;0.934), p = 0.028). Higher VSR was associated with mortality (OR = 2.147, 95%CI=(1.022;4.512), p = 0.044). Male sex showed the strongest influence on the risk of ICU admission and MV. SMI was not associated with either parameter. CONCLUSION: In patients hospitalized for Covid-19 infection, higher VSR seems to be a strong prognostic factor of short-term mortality. Weak associations with clinical course were found for MD and adipose tissue measurements. Male sex was the strongest prognostic factor of adverse clinical course. ADVANCES IN KNOWLEDGE: VSR is a prognostic biomarker for 30-day mortality in patients hospitalized for Covid-19 disease.

Prognostic Role of the Pectoralis Musculature in Patients with COVID-19. A Multicenter Study.

RATIONALE AND OBJECTIVES: To evaluate the impact of low skeletal muscle mass in patients with COVID-19 on relevant outcomes like 30-day mortality, need for intubation and need for intensive care unit admission. MATERIALS AND METHODS: For this study, data from six centers were acquired. The acquired sample comprises 1138 patients. There were 547 women (48.1%) and 591 men (51.9%) with a mean age of 54.5 ± 18.8 years; median age, 55 years; range, 18-84 years). In every case, thoracic CT without intravenous application of contrast medium was performed. The following parameters of the pectoralis muscles were estimated: muscle area as a sum of the bilateral areas of the pectoralis major and minor muscles, muscle density, muscle index (PMI) (pectoralis muscle area divided by the patient's body height square) as a ratio pectoralis major and minor muscles divided by the patient's body height2, and muscle gauge as PMI x muscle density. RESULTS: Overall, 220 patients (19.33%) were admitted to the intensive care unit. In 171 patients (15.03%), mechanical lung ventilation was performed. Finally, 154 patients (13.53%) died within the observation time of 30-day. All investigated parameters of pectoralis muscle were lower in the patients with unfavorable courses of Covid-19. All pectoralis muscle parameters were associated with 30-day mortality in multivariate analyses adjusted for age and sex: pectoralis muscle area, HR = 0.93 CI 95% (0.91-0.95) p < 0.001; pectoralis muscle density, HR = 0.94 CI 95% (0.93-0.96) p < 0.001; pectoralis muscle index, HR = 0.79 CI 95% (0.75-0.85) p < 0.001, pectoralis muscle gauge, HR = 0.995 CI 95% (0.99-0.996) p < 0.001. CONCLUSION: in COVID-19, survivors have larger areas and higher index, gauge and density of the pectoralis muscles in comparison to nonsurvivors. However, the analyzed muscle parameters cannot be used for prediction of disease courses.

SPECT/CT Lymphoscintigraphy Guidance Simplifies and Improves Targeted Axillary Dissection of the Clipped Nodes After Neoadjuvant Chemotherapy in Initially Node-Positive Breast Cancer.

PURPOSE: We assessed the feasibility of SPECT/CT lymphoscintigraphy ( 99m Tc-nanocolloid) method to simplify and improve targeted axillary dissection of clipped axillary lymph node (axLN) after neoadjuvant chemotherapy (NAC) in initially node-positive breast cancer. PATIENTS AND METHODS: Fifteen patients who had clip placement to biopsy-confirmed axLN metastasis due to clinically node-positive breast cancer before NAC and underwent SPECT/CT lymphoscintigraphy for surgery after NAC were included into the study. SPECT/CT lymphoscintigraphy was performed to localize the clipped node and to assess if the clipped lymph node (LN) had 99m Tc-nanocolloid uptake or not. In case the clipped node had no uptake on SPECT/CT, the patient was referred to wire-guided localization procedure. Blue dye was also injected for dual mapping of sentinel LN biopsy. RESULTS: All patients had only ipsilateral axLN metastasis. SPECT/CT lymphoscintigraphy showed that clipped LNs were radioavid in 12 of 15 patients (80%). Clipped LNs were not blue-stained in 5 patients (33.3%), and in 2 of them, clipped LNs were radioavid in SPECT/CT. Wire-guided localization was required in only 3 patients (20%) for nonradioavid/blue-stained clipped LNs. Removal of the clipped nodes was confirmed in all cases with a success rate of 100% by specimen graphy. CONCLUSION: SPECT/CT lymphoscintigraphy seems feasible to determine the clipped LNs intraoperatively without requiring additional invasive methods in most of the patients. This technique simplifies and improves targeted axillary dissection of the clipped axLNs after NAC in initially node-positive breast cancer and can be adapted to clinical practice with further investigations.

Pancreatic MR imaging and endocrine complications in patients with beta-thalassemia: a single-center experience.

Iron deposition in various organs can cause endocrine complications in patients with transfusion-dependent beta-thalassemia. The aim was to investigate the relationship between endocrine complications and pancreatic iron overload using magnetic resonance imaging (MRI). Forty patients with transfusion-dependent thalassemia (TDT) were enrolled in the study. The magnetic resonance imagings of the patients were performed using a 1.5 Tesla Philips MRI scanner. Two out of three patients had at least one clinical endocrine complication. The rate of iron deposition was 62.5% in liver, and 45% in pancreas tissue, and was 12.5% in heart tissue. Pancreatic T2* and hepatic T2* values were significantly positively correlated (p = 0.006). Pancreatic T2* and ferritin were significantly negatively correlated (p = 0.03). Cardiac T2* values were negatively correlated with fasting blood glucose (p = 0.03). Patients with short stature had significantly higher cardiac iron burden (22.3 vs. 36.6 T2*ms; p 0.01), and patients with hypothyroidism had higher liver iron concentrations (9.9 vs. 6.4 LIC mg/g; p = 0.05). The ferritin level of 841 ng/mL and liver iron concentration (LIC) value of 8.7 mg/g were detected as the threshold level for severe pancreatic iron burden (AUC 70%, p:0.04, AUC 80%, p = 0.002, respectively). Moreover, males were found to have decreased pancreas T2* values compared with the values in females (T2* 19.3 vs. 29.9, p = 0.05). Patients with higher ferritin levels over than 840 ng/mL should be closely monitored for pancreatic iron deposition, and patients with endocrine complications should be assessed in terms of cardiac iron burden.

Impact of Multimodality Imaging on the Diagnosis of Left Ventricular Apical Thrombus in Patients After Anterior Myocardial Infarction.

BACKGROUND: The presence of the left ventricle (LV) apical thrombus is one of the most critical complications of anterior myocardial infarction (MI). Due to the high risk of systemic embolization, the determination of LV apical thrombus (LVAT) is essential. We aimed to compare the two-dimensional echocardiography (2DE), contrast-2DE and real-time three-dimensional echocardiography (RT-3DE) in the diagnosis of LVAT and determine which imaging modality is superior. METHODS: The study was designed as a prospective cohort study, and 161 patients were included. Patients with low ejection fraction (< 40%) and LV apical wall motion abnormality (severe hypokinetic, akinetic or dyskinetic) were included. 2DE, contrast-2DE, RT-3DE, and magnetic resonance imaging (MRI) were performed on all patients within one month after anterior MI. RESULTS: Transthoracic 2DE detected thrombi in 29 patients, contrast-2DE detected thrombi in 33 patients, RT-3DE detected thrombi in 32 patients, and MRI detected thrombi in 28 patients. While MRI is accepted as the gold standard for non-invasive imaging, the specificity of detecting thrombus with 2DE is 90%, and the sensitivity is 57%, contrast-2DE had 82% sensitivity and 92% specificity for the detection of LVAT. The specificity for detecting thrombus with RT-3DE is 93%, and the sensitivity is 85%. Accuracy was 84%, 90% and 92% with 2DE, contrast-2DE and RT-3DE, respectively. CONCLUSIONS: We found that RT-3DE was more sensitive and more specific than 2DE and contrast-2DE in the diagnosis of LVAT. The diagnostic accuracy of RT-3DE was higher than 2DE and contrast-2DE for LVAT.

Intracardiac masses: Single center experience within 12 years: I-MASS Study.

Objective: The aim of this cross-sectional, retrospective, descriptive study was to review and classify cardiac masses systematically and to determine their frequencies. Methods: The medical records of 64,862 consecutive patients were investigated within 12 years. Every patient with a cardiac mass imaged by transthoracic echocardiography (TTE) and confirmed with an advanced imaging modality such as transesophageal echocardiography (TEE), computed tomography (CT) and/or cardiac magnetic resonance imaging (CMR) was included. Acute coronary syndromes triggering thrombus formation, vegetations, intracardiac device and catheter related thrombi were excluded. Results: Data demonstrated 127 (0.195%) intracardiac masses consisting of 33 (0.050%) primary benign, 3 (0.004%) primary malignant, 20 (0.030%) secondary tumors, 3 (0.004%) hydatid cysts and 68 (0.104%) thrombi respectively. The majority of primary cardiac tumors were benign (91.67%), predominantly myxomas (78.79%), and the less malignant (8.33%). Secondary cardiac tumors were common than the primary malignant tumors (20:3), with male dominancy (55%), lymphoma and lung cancers were the most frequent. Intracardiac thrombi was the majority of the cardiac masses, thrombi accompanying malignancies were in the first range (n = 17, 25%), followed by autoimmune diseases (n = 13, 19.12%) and ischemic heart disease with low ejection fraction (n = 12, 17.65%). Conclusions: This retrospective analysis identified 127 patients with cardiac masses. The majority of benign tumors were myxoma, the most common tumors that metastasized to the heart were lymphoma and lung cancers, and the thrombi associated with malignancies and autoimmune diseases were the most frequent.

Effect of trabeculated myocardial mass on left ventricle global and regional functions in noncompaction cardiomyopathy.

BACKGROUND: Left ventricular (LV) noncompaction cardiomyopathy is a rare cardiomyopathic subtype that has been recognized in recent years and is being diagnosed at an increased rate. There is no consensus regarding the diagnosis of the disease, and increased trabeculation rates that meet the existing diagnostic criteria may even be present in healthy asymptomatic people. This indicates that differentiating criteria for diagnosis are needed. AIM: To examine the increase in myocardial trabeculation and the change in left ventricular global and regional functions. METHODS: This retrospective study included 65 patients (28 females, 37 males) diagnosed with LV noncompaction cardiomyopathy who underwent cardiac magnetic resonance imaging between January 2011 and August 2016 and had a noncompacted/compacted myocardial thickness ratio of over 2.3 in more than one segment in the left ventricle. The distribution and ratios of trabeculations in apical, midventricular, and basal regions were examined in short-axis images obtained from cardiac magnetic resonance. In addition, by using short-axis cine images, regional ejection fraction (EF) and global EF were calculated using the Simpson method in the left ventricle at apical, basal, and midventricular levels. RESULTS: While the number of trabeculated segments were similar at the apical (3.2 ± 1.0) and midventricular levels, a statistically significant level of involvement was not observed at the basal level (0.4 ± 0.9) (P > 0.05). The highest noncompacted/compacted (trabeculation) ratio was observed at the apical level (3.9 ± 1.4), while this ratio was higher at the anterior (59%-89.4%) and lateral (62%-84.8%) segments (P > 0.05). Global EF was positively correlated with apical, midventricular, and basal regional EF (P < 0.05). However, there was no significant correlation between regional EF and the number of trabeculated segments or trabeculation ratio in all three regions; nor was there a significant correlation between regional EF and the number of trabeculated segments or trabeculation ratio in the entire LV (P > 0.05). CONCLUSION: No global or regional relationship was observed between LV dysfunction and trabeculation rate or the number of trabeculated segments. This limits the usefulness of change in LV functions in the differentiation between normal and pathological trabeculation.

Comparison between body composition parameters and response to neoadjuvant chemotherapy by using pre-treatment PET CT in locally advanced breast cancer.

PURPOSE: To compare the adipose and muscle tissue areas in patients who responded differently to neoadjuvant chemotherapy. METHODS: One hundred and eighty six patients diagnosed with breast cancer who underwent neoadjuvant chemotherapy between January 2015- October 2019 and were operated after the treatment were retrospectively included in the study. Pathological results were divided into five groups using the Miller-Payne grading systems. Grade 1 indicating no significant reduction in malignant cells; Grade 2: a minor loss of malignant cells (≤ 30 %); Grade 3: reduction in malignant cells between 30 % and 90 %; Grade 4: disappearance of malignant cells >90 %; Grade 5: no malignant cells identifiable. Pre-treatment PET CT scans were evaluated, and calculation of body composition parameters were performed on a single axial section passing through the L3 vertebrae. Spearman's correlation test was used to analyze the correlation between SAT, VAT, MT parameters and pathological responses. RESULTS: There was no strong correlation between the 5 groups separated according to neoadjuvant chemotherapy treatment response and tissue distributions. However, that there was a very low correlation found between superficial adipose tissue and pathological response (r=, 156). CONCLUSION: In conclusion, our results have provided a very low correlation between SAT and more than 30 % response. More research is required to evaluate the role of the body fat and muscle parameters in response to neoadjuvant chemotherapy in larger patient populations.

Pituitary Iron Deposition and Endocrine Complications in Patients with ß-Thalassemia: From Childhood to Adulthood.

The endocrinological complications are a great concern in transfusion-dependent ß-thalassemia (ß-thal) patients. The pituitary iron deposition is regarded as the main cause of hormonal changes in thalassemic patients. In this study, our aim was to explore the association between endocrinological complications and pituitary iron overload by magnetic resonance imaging (MRI). Fifty transfusion-dependent thalassemia (TDT) patients were recruited for the study. Pituitary MRIs of patients were taken using a 1.5 Tesla Philips MRI machine. There was at least one clinical endocrine complication in two of three patients. The iron accumulation was moderate in the liver (60.0%) and was mild in hypophysis (16.0%) and in heart (8.0%). The hypogonadism and diabetes mellitus (DM) were not seen with a significantly increased pituitary iron burden. The hypogonadism was related to cardiac iron deposition (p = 0.04). The short stature was associated with a hepatic iron overload (p = 0.05). The conventional follow-up of patients with TDT might be inadequate and screening of patients with MRI of hypophysis along with heart and liver leads to better results.

Magnetic resonance imaging characteristics of cardiac hydatid cyst.

PURPOSE: The purpose of this article is to describe the magnetic resonance imaging (MRI) features of cardiac hydatid disease and show the specific findings in the diagnosis of hydatic cysts. MATERIALS AND METHODS: A retrospective review of cardiac MRI records between 2015 and 2017, 7 patients (3 males, 4 females; age range: 14-74) were identified with the histologic diagnosis of cardiac hydatid disease. Cardiac MRI examinations were performed in order to investigate the cardiac cystic-solid lesion obtained via previous echocardiography (ECG) and thorax computed tomography. 1.5 Tesla magnetic field power generation capacity was used and the images were acquired with ECG trigger. RESULTS: There is variation in signal characteristics of cysts on T1-weighted and T2-weighted images. Early contrast enhancement was not observed in the any of lesions on contrast-enhanced series. In all lesions examined, peripheral contrast enhancement was observed in the late contrast enhanced series, independent from the internal structure and signal intensity. CONCLUSIONS: MRI reveals the exact anatomic location and nature of the cyst structures. Peripheral enhancement of non-enhancing lesion is very valuable for diagnosis of cardiac hydatids on MRI.

Magnetic resonance imaging during management of patients with transfusion-dependent thalassemia: a single-center experience.

BACKGROUND: Cardiac and hepatic magnetic resonance imaging evaluation during treatment can tailor physicians' chelation therapy titrations. AIM: The aim of the study was to assess the relationship of cardiac and hepatic T2* values with chelation therapy in patients with transfusion-dependent thalassemia (TDT). METHODS: A total of 106 patients with TDT who were followed up in Istanbul Medical Faculty Thalassemia Center were evaluated for the study. Forty-eight (45%) patients with TDT had more than one consecutive MRI examination. The patients were divided into three subgroups according to the cardiac T2* values as the high-risk group (T2* MRI < 10 ms), medium-risk group (T2* MRI 10-20 ms), and the low-risk group (T2* MRI > 20 ms). RESULTS: The majority of patients used DFX (deferasirox) (79%) and deferiprone (DFP) (17%). Approximately 80% of patients according to cardiac T2* value and 40% of patients according to hepatic T2* value were initially in the low-risk group. Patients with follow-up MRI examinations exhibited significant improvement in liver iron concentration, which correlated with an increase in hepatic T2* values. The decrease of liver iron concentration was prominent in the DFX group (p < 0.01). The serum ferritin level was significantly correlated with liver iron concentrations (rs = 0.65, p < 0.001), hepatic T2* value (rs = - 0.62, p < 0.001), but not with cardiac T2* value (rs = - 0.20, p = 0.07). CONCLUSION: Cardiovascular and hepatic MRI is a useful follow-up tool during the assessment of risk groups and chelation therapy of patients with TDT. Consecutive MRI tests showed good monitoring of cardiac and liver iron overload.

Stromal fibrosis: imaging features with diagnostic contribution of diffusion-weighted MRI.

OBJECTIVE: To describe magnetic resonance imaging (MRI) and ultrasonography findings of breast stromal fibrosis (SF) and compare apparent diffusion coefficient (ADC) stromal fibrosis values with breast cancer and normal parenchyma. METHODS: 45 patients (ages 22‒74) with histopathologically proven SF who underwent MRI were included in this study. Their MRI and ultrasonography features were examined and categorized. The mean ADC values for SF, contralateral normal parenchyma, and breast malignancy of the control group values were calculated and compared among each other. RESULTS: The vast majority of SF on sonography showed features suggestive of malignancy: (1) irregular in shape 25/45 (55%); (2) indistinct in margin 27/45 (60%); and (3) hypoechoic 39/45 (87%) with posterior acoustic shadowing 11/45 (24%). An SF MRI showed a mass in 12/45 (26%) and non-mass enhancement in 33/45 (74%), mostly with irregular (8/12; 67%) shape. Non-mass lesions showed heterogeneous (12/33), clumped (9/33), and homogenous (9/33) enhancement. The initial SF contrast uptake rate varied between slow (57%), rapid (22%), and medium (21%). Delayed SF enhancement may be persistent (66%) or plateau (34%). Small cysts were located around/near 21 (47%) of lesions. Ductal ectasia was found in 14 (31%) of all patients. Mean ADCs of parenchyma, SF, and malignancy were 1.32 ± 0.32, 1.23 ± 0.25, and 0.99 ± 0.24 × 10-3 mm2 sec-1, respectively. CONCLUSION: SF often mimics breast carcinoma on imaging and leads the radiology‒pathology disagreement. In terms of distinguishing SF from malignancy, ADC could be a significant and promising value in diffusion-weighted MRI along with conventional sequences. Slow initial uptake with delayed persistent contrast enhancement in a non-mass lesion with relatively higher ADC values are very helpful for differentiating SF from malignancy. The presence of small cysts and ductal ectasia were common findings around/near the SF. Advances in knowledge: A quantitative analysis for measuring ADC values along with additional MRI features can be very helpful in distinguishing SF from malignant lesions.

Myofibroblastoma of the Breast: Ultrasonography, Mammography, and Magnetic Resonance Imaging Features With Pathologic Correlation.

Myofibroblastoma (MFB) of the breast is an uncommon benign stromal tumor. Herein, we present histopathologically proven MFB that hyperechoic well-defined breast mass in the ultrasonography and circumscribed high-density mass in mammography. Additionally, internal septations and hyperintense appearance on magnetic resonance imaging are very valuable findings in the differential diagnosis of MFB.

MR Imaging Features of Tubular Carcinoma: Preliminary Experience in Twelve Masses.

OBJECTIVE: We retrospectively analyzed the magnetic resonance (MR) imaging features and diffusion-weighted imaging findings of the 12 masses of 10 patients with tubular carcinoma (TC), including mammography and sonography findings. MATERIALS AND METHODS: Mammographic, sonographic and magnetic resonance imaging features in 12 histopathologically confirmed masses diagnosed as TC of the breast within 10 patients were evaluated. Morphologic characteristics, enhancement features, apparent diffusion coefficient (ADC) values were reviewed. RESULTS: On mammography (n=5), TC appeared as high density masses with indistinct, spiculated or obscured margins. Sonographically, TC appeared as a hypoechoic appearance (n=12) with posterior acoustic shadowing in nine. On MR imaging, the margins of ten of twelve masses were irregular. Internal enhancement patterns were heterogeneous in 10 patients. Dynamic enhancement patterns illustrated plateau kinetics (n=8). On the T2-weighted images 4 masses were hypointense, and 8 were hyperintense; hypointense internal septation was found in seven of these. Tubular carcinoma appeared as hyperintense on diffusion-weighted imaging with ADC values of 0.85±0.16×10-3 mm2/s that was lower than the normal parenchyma of 1.25±0.25×10-3 mm2/s. CONCLUSION: According to our study with a limited number of cases, tubular carcinomas can be described as hyperintense breast carcinomas with or without dark internal septation like appearance on T2-weighted images. Low ADC values from DW imaging can be used to differentiate TC from hyperintense benign breast lesions.

Muscle magnetic resonance imaging in spinal muscular atrophy type 3: Selective and progressive involvement.

INTRODUCTION: In this study we sought to identify magnetic resonance imaging (MRI) signs of selective muscle involvement and disease progression in patients with spinal muscular atrophy type 3b (SMA3b). METHODS: Twenty-five patients with genetically confirmed SMA3b underwent MRI on a 1.5-Tesla MR scanner. RESULTS: MRI showed significantly more severe involvement of the iliopsoas than of the gluteus maximus muscles, and more severe involvement of the triceps brachii than of the biceps brachii muscles. The quadriceps femoris muscles were severely involved. The deltoid, adductor longus, portions of the hamstrings, gracilis, sartorius, and rectus abdominis muscles were well preserved. We found a significant positive correlation between MRI changes and disease duration for gluteus maximus and triceps brachii. Follow-up MRIs of 4 patients showed disease progression. CONCLUSIONS: This study confirms the pattern of selective muscle involvement suggested by previous studies and further refines muscle MRI changes in SMA3b. Progressive muscle involvement is implicated. Muscle Nerve 55: 651-656, 2017.

Cardiac calcified amorphous tumors: CT and MRI findings.

PURPOSE: We aimed to evaluate computed tomography (CT) and magnetic resonance imaging (MRI) findings of cardiac calcified amorphous tumors (CATs). METHODS: CT and MRI findings of cardiac CATs in 12 patients were included. We retrospectively examined patient demographics, location, size, shape configuration, imaging features, calcification distribution of tumors, and accompanying medical problems. RESULTS: There was a female predominance (75%), with a mean age at presentation of 65 years. Patients were mostly asymptomatic on presentation (58.3%). The left ventricle of the heart was mostly involved (91%). CT findings of CATs were classified as partial calcification with a hypodense mass in four patients or a diffuse calcified form in eight. Calcification was predominant with large foci appearance as in partially calcified masses. On T1- and T2-weighted magnetic resonance images, CATs appeared hypointense and showed no contrast enhancement. CONCLUSION: The shape and configuration of cardiac CATs are variable with a narrow spectrum of CT and MRI findings, but large foci in a partially calcified mass or diffuse calcification of a mass on CT is very important in the diagnosis of cardiac CATs. Masses show a low signal intensity on T1- and T2-weighted images with no contrast enhancement on MRI.

Magnetic resonance imaging features of idiopathic granulomatous mastitis: is there any contribution of diffusion-weighted imaging in the differential diagnosis?

PURPOSE: To identify the magnetic resonance imaging (MRI) appearance of idiopathic granulomatous mastitis, and the usefulness of diffusion-weighted magnetic resonance imaging (DW-MRI) in distinguishing idiopathic granulomatous mastitis (IGM) from malignant breast lesions. MATERIAL AND METHODS: A total of 37 women (mean age 36 + 8; range 20-67 years) with histopathologic diagnoses of idiopathic granulomatous mastitis were enrolled in the study. Five patients had bilateral IGM, which were evaluated as ten cases. Dynamic MRI findings were categorized as enhancing mass lesion, non-mass enhancement, or both together. The frequency of quadrant involvement, retroareolar involvement, accompanying abscess, ductal ectasia, skin thickening, breast edema, extension to pectoral muscle, and presence of fistula were investigated. The mean apparent diffusion coefficient (ADC) values for lesions, contralateral normal breast parenchyma, pectoralis major muscle, and sternum were measured in patients with invasive cancers (n = 42) and those with mastitis (n = 42). The ADC ratio of the lesions to the contralateral normal breast parenchyma, pectoralis major muscle, and sternum were determined. RESULTS: The findings of idiopathic granulomatous mastitis on MRI were total (in all quadrants) or wide (2 or 3 quadrants) in 30 (71.5 %), retroareolar space involvement in 28 (66.7 %), skin thickening in 21 (50 %), breast edema in 21 (50 %), extension to pectoral muscle in 18 (42.9 %), accompanying abscess formation in 33 (78 %), ductal ectasia in 17 (40.5 %), and fistulas in 13 (31 %). On dynamic contrast-enhanced MRI, 69 % of the patients had mass appearance of IGM. The most frequent enhancement patterns were rim enhancement in 20 (78 %) in masses and clustered ring in 11 (48 %) in non-mass lesions. Early enhancement pattern of IGM was obtained as 'slow' in 29 cases (69 %), 'medium' in 11 cases (26.1) and 'rapid' in 2 (5 %) cases. Time-signal intensity curves were detected as Type-1 in 27 cases (64 %) and Type-2 in 15 cases (36 %). IGM showed significantly lower mean ADC values when compared with the normal parenchyma. When IGM was compared with malignancy, mastitis ADC was 0.98 ± 0.188 × 10-3, and invasive cancer ADC was 0.95 ± 0.229 × 10-3. The difference in ADC values of mastitis and invasive cancers proved not to be significant (P = 0.185). Our results had no discriminatory power for IGM versus malignant lesions for either ADC values and ADC ratios of normal breast parenchyma, pectoralis major muscle, and sternum. CONCLUSION: Although not characteristic for idiopathic granulomatous mastitis, masses with rim enhancement or clustered-ring non-mass lesions with segmental distribution on MRI are the most common features of the disease. Ductal ectasia and periductal enhancement were commonly accompanying; this and kinetic analysis are valuable findings for distinguishing IGM from invasive cancer. IGM shows similar ADC values to invasive cancers despite being benign, DW-MRI is not helpful in the differentiation with malignant lesions.