Lower Apparent Diffusion Coefficient Values Research Articles

The value of multimodal magnetic resonance imaging in breast cancer and its correlation with pathological features and prognosis.

This study aimed to explore the diagnostic value of multimodal magnetic resonance imaging (MRI) in breast cancer (BC) and its correlation with pathological features of the disease. Clinical data of 85 BC patients (malignant group) and 85 patients with benign breast diseases (benign group), admitted to 3201 Hospital of Xi'an Jiaotong University Health Science Center from May 2020 to May 2022, were retrospectively collected. Both groups underwent multimodal MRI examinations. We compared the differences in multimodal MRI examination parameters between the groups, as well as between patients with different pathological characteristics and prognoses in the malignant group. The correlation between multimodal MRI examination parameters and pathological features of BC was analyzed. The apparent diffusion coefficient (ADC) of the malignant group was lower than that of the benign group, while the extravascular extracellular volume fraction (Ve), reaction rate constant (Kep), and volume transfer constant (Ktrans) of the malignant group were higher compared to the benign group (p<0.05). In the malignant group, patients with stage III+IV disease, lymph node metastases, and low differentiation had lower ADC values, and higher Ve, Ktrans, and Kep compared to patients with stage I+II disease, no lymph node metastasis, and medium to high differentiation (p<0.05). ADC value negatively correlated with the stage of the disease, lymph node metastases but positively correlated with the degree of differentiation (p<0.05). Ve, Ktrans, and Kep positively correlated with the stage of the disease and lymph node metastasis, and negatively correlated with the degree of differentiation (p<0.05). ADC value of patients with poor prognosis was lower, while Ve, Ktrans, and Kep were higher compared to patients with good prognosis (p<0.05). The Receiver operating characteristic (ROC) analysis showed that ADC, Ve, Ktrans, and Kep have certain predictive values for the poor prognosis of BC patients (p<0.05). Multimodal MRI examination detected obvious differences in the examination parameters of BC patients, and the increase or decrease in these parameters is closely correlated with the pathological characteristics and prognosis of the disease. Multimodal MRI examination can be used for pathological evaluation and prognosis prediction in BC patients.

Microstructural Brain Development and Neurodevelopmental Outcome of Very Preterm Infants of Mothers with Gestational Diabetes Mellitus

Introduction: There are data linking gestational diabetes mellitus (GDM) with adverse neurodevelopmental outcome in the offspring. We investigated the effect of GDM on microstructural brain development and neurodevelopmental outcome of very preterm infants. Materials and Methods: Preterm infants <32 gestational weeks of mothers with GDM obtained cerebral magnetic resonance imaging (MRI) including diffusion-tensor imaging at term-equivalent age. For every infant, two gestational age-, sex-, and MRI scanner type-matched controls were included. Brain injury was assessed and fractional anisotropy (FA) and apparent diffusion coefficient (ADC) measured in 14 defined cerebral regions. Neurodevelopmental outcome was quantified at the corrected age of 24 months using the Bayley Scales of Infant Development. Results: We included 47 infants of mothers with GDM and 94 controls. There were no differences in neonatal morbidity between the groups, nor in any type of brain injury. The GDM group showed significantly higher FA values in the centrum semiovale, the posterior limb of the internal capsule and the pons bilaterally, in the corpus callosum and the right occipital white matter, as well as lower ADC values in the right centrum semiovale, the right occipital white matter and the corpus callosum. Neurodevelopmental outcome did not differ between the groups. Conclusion: We found no impairment of brain development in GDM-exposed infants compared to matched controls, but differences in white matter microstructure in specific regions indicating an enhanced maturation. However, neurodevelopmental outcome was equal in both groups. Further studies are needed to better understand brain maturation in preterm infants exposed to GDM.

Pretreatment diffusion-weighted imaging for prediction of relapsed and refractory primary central nervous system lymphoma.

A subset of primary central nervous system lymphoma (PCNSL) has been shown to undergo an early relapsed/refractory (R/R) period after first-line chemotherapy. This study investigated the pretreatment clinical and MRI features to predict R/R in PCNSL, emphasizing the apparent diffusion coefficient (ADC) values in diffusion-weighted imaging (DWI). This retrospective study investigated the pretreatment MRI features for predicting R/R in PCNSL. Only patients who had undergone complete preoperative and postoperative MRI follow-up studies were included. From January 2006 to December 2021, 52 patients from two medical institutions with a diagnosis of PCNSL were included (median follow-up time, 26.3 months). Among these, 24 (46.2%) had developed R/R (median time to relapse, 13 months). Cox proportional hazard regression analyses were performed to determine hazard ratios for all parameters. Significant predictors of R/R in PCNSL were female sex, complete response (CR) to first-line chemotherapy, and ADC value/ratio (p < 0.05). Cut-off points of ADC values and ADC ratios for prediction of R/R were 0.68 × 10-3 mm2/s and 0.97, with AUCs of 0.78 and 0.77, respectively (p < 0.05). Multivariate Cox proportional hazards analysis showed that failure of CR to first-line chemotherapy and low ADC values (<0.68 × 10-3 mm2/s) were significant risk factors for R/R, with hazard ratios of 5.22 and 14.45, respectively (p < 0.05). Kaplan-Meier analysis showed that lower ADC values and ratios predicted significantly shorter progression-free survival (p < 0.05). Pretreatment ADC values in DWI offer quantitative valuable information for the treatment planning in PCNSL.

Evaluation of breast cancer malignancy, prognostic factors and molecular subtypes using a continuous-time random-walk MR diffusion model

PurposeTo assess the continuous-time random-walk (CTRW) model’s diagnostic value in breast lesions and to explore the associations between the CTRW parameters and breast cancer pathologic factors. MethodThis retrospective study included 85 patients (70 malignant and 18 benign lesions) who underwent 3.0T MRI examinations. Diffusion-weighted images (DWI) were acquired with 16b-values to fit the CTRW model. Three parameters (Dm, α, and β) derived from CTRW and apparent diffusion coefficient (ADC) from DWI were compared among the benign/malignant lesions, molecular prognostic factors, and molecular subtypes by Mann-Whitney U test. Spearman correlation was used to evaluate the associations between the parameters and prognostic factors. The diagnostic performance was assessed by the area under the receiver operating characteristic curve (AUC) based on the diffusion parameters. ResultsAll parameters, ADC, Dm, α, and β were significantly lower in the malignant than benign lesions (P < 0.05). The combination of all the CTRW parameters (Dm, α, and β) provided the highest AUC (0.833) and the best sensitivity (94.3%) in differentiating malignant status. And the positive status of estrogen receptor (ER) and progesterone receptor (PR) showed significantly lower β compared with the negative counterparts (P < 0.05). The high Ki-67 expression produced significantly lower Dm and ADC values (P < 0.05). Additionally, combining multiple CTRW parameters improved the performance of diagnosing molecular subtypes of breast cancer. Moreover, Spearman correlations analysis showed that β produced significant correlations with ER, PR and Ki-67 expression (P < 0.05). ConclusionsThe CTRW parameters could be used as non-invasive quantitative imaging markers to evaluate breast lesions.

Differentiation of glioblastoma, brain metastases and central nervous system lymphomas using amount of vasogenic edema and diffusion MR imaging of tumor core and peritumoral zone- Searching for a practical approach

Background/Aim: The differential diagnosis of solitary brain tumors poses challenges for clinicians and radiologists, often leading to invasive biopsy procedures. Therefore, this study aimed to evaluate the variations in edema volume and diffusion characteristics between the tumor core and peritumoral zone in cases of glioblastoma, brain metastasis, and central nervous system lymphoma. The aim was to identify additional parameters for conventional magnetic resonance imaging (MRI) that could aid in the differential diagnosis. Methods: A total of 39 patients (13 with central nervous system lymphoma, 13 with glioblastoma, and 13 with brain metastases) were included in this retrospective cohort study. Apparent diffusion coefficient (ADC) values were calculated from the ADC maps obtained from Brain MRI for both the lesion and peritumoral region. Additionally, the largest diameter of the vasogenic edema-mass complex was measured using T2 sequences. In the contrast-enhanced series, the largest diameter of the metastatic lesion was measured. The edema-mass ratio was determined by dividing the diameter of the edema-mass complex by the diameter of the mass. Results: There was a statistically significant difference in the edema-mass ratio among the tumor types (P=0.008). Further analysis using Bonferroni correction revealed that this difference was primarily due to glioblastoma. Compared to patients with lymphoma and brain metastases, lesions diagnosed as glioblastoma exhibited a lower edema-mass ratio. Additionally, a statistically significant difference was observed in the ADC value measured from the lesion according to the tumor type (P=0.017). It was determined that lesions associated with central nervous system lymphoma had lower ADC values than those with glioblastoma. Conclusion: Including lesional and perilesional ADC values obtained through diffusion-weighted examination and edema mass ratio measurements may enhance the accuracy of differential diagnosis. Utilizing these imaging characteristics in a multiparametric approach, as suggested by this research, can improve the accuracy of diagnosing malignant cancers, thereby enabling better patient management and treatment decisions.

Preoperatively Identify the Microvascular Invasion of Hepatocellular Carcinoma with the Restricted Spectrum Imaging

To noninvasively and preoperatively identify the microvascular invasion (MVI) of hepatocellular carcinoma (HCC) with the restricted spectrum imaging (RSI). 62 patients were included into this prospective study and underwent the RSI examination with a 3.0-T scanner. Mono-exponential diffusion-weighted imaging-derived apparent diffusion coefficient (ADC) and RSI-derived metrics including f1 (fraction of restricted diffusion), f2 (fraction of hindered diffusion), f3 (fraction of free diffusion), and f1f2 (the multiply of f1 and f2) were calculated. Univariate and multivariate logistic regression were used to select the independent risk factors. Nomogram-based model was constructed with the selected indexes. Receiver operative characteristics analysis and calibration curve were used to evaluate the diagnostic accuracy. MVI-positive HCC showed significantly higher f1 and lower ADC values (ADC: 1.549±0.228×10-3 vs 1.365±0.239×10-3 mm2/s, P= .003; f1: 0.1633±0.0341 vs 0.2221±0.0491, P<.001). Tumor size and f1 were selected as independent risk factors for MVI. The nomogram-based model was then constructed with tumor size and f1. Nomogram-based model (area under ROC curve [AUC]=0.856) yielded the best diagnostic accuracy followed by f1 (AUC=0.842) and ADC (AUC=0.708). The AUC of both the f1 and nomogram model were significantly higher than that of ADC. RSI-derived metrics can be utilized to noninvasively and efficiently identify the MVI of HCC. Considering the importance of MVI as a significant prognostic factor for HCC, the utilization of RSI has the potential to assist in prognostic prediction and clinical management.

Association of quantifiable prostate MRI parameters with any and large cribriform pattern in prostate cancer patients undergoing radical prostatectomy

PurposeCribriform pattern has recently been recognized as an important independent risk factor for prostate cancer (PCa) outcome. This study aimed to identify the association of quantifiable prostate magnetic resonance imaging (MRI) parameters with any and large cribriform pattern at radical prostatectomy (RP) specimens. MethodsPreoperative prostate MRI’s from 188 men undergoing RP between 2010 and 2018 were retrospectively acquired. RP specimens of the patients were revised for Gleason score (GS), and presence of any and large cribriform pattern. MRI parameters such as MRI visibility, PI-RADS score, lowest apparent diffusion coefficient (ADC) value, lesion size, and radiologic extra-prostatic extension (EPE) were reviewed. The association of prostate MRI parameters for presence of any and large cribriform pattern at RP was analysed using logistic regression. Results116/188 (61.7%) PCa patients had any cribriform and 36/188 (19.1%) large cribriform pattern at RP. 171/188 (91.0%) men had MRI-visible lesions; 111/116 (95.7%) tumours with any and 36/36 (100%) with large cribriform pattern were visible at MRI. PCa with any and large cribriform pattern both had lower ADC values than those without (p < 0.001). In adjusted analysis, lowest ADC value was as an independent predictor for any cribriform (Odds Ratio (OR) 0.2, 95% Confidence Interval (CI) 0.1–0.8; p = 0.01) and large cribriform pattern (OR 0.2, 95% CI 0.1–0.7; p = 0.01), while other parameters were not. ConclusionsThe majority of PCa with cribriform pattern at RP were visible at MRI, and lowest ADC value was an independent predictor for both any and large cribriform pattern.

#3587 INTERMITENT RECURRENT HYPONATREMIA: A NEW EXPERIMENTAL MODEL – A STUDY ON ITS EFFECTS ON WATER BALANCE AND CENTRAL NERVOUS SYSTEM

Abstract Background and Aims Hyponatremia is the most common electrolyte disturbance in clinical care. Even mild presentations are associated with poor prognosis and increased mortality, in spite of which there is a trend to minimize the importance of small variations in natremia, that have historically been dismissed as not having negative consequences despite growing evidence against it. In this regard, it has not been studied to date whether an intermittent but recurrent hyponatremia is relevant. There are clinical scenarios where this condition could occur and be overlooked, such as cirrhosis or heart failure. Method Different rat models have been used to study the effects of different hypotonic situations on the electrolyte balance and central nervous system: intermittent recurrent hyponatremia (intraperitoneal (i.p.) daily dose of desmopressin acetate (ddAVP) and a water dose equivalent to 2.5% of the animal's body weight in hyposodic diet fed animals), acute on intermittent recurrent hyponatremia (i.p. water overload equivalent to 10% of the animal's body weight in animals subjected to intermittent recurrent hyponatremia) and acute hyponatremia (i.p. administration of a 10% of the animal's body weight water overload in chow fed animals). Apparent diffusion coefficient (ADC) obtained from diffusion weighted images (DWI) acquired through magnetic resonance (7T Bruker Biospec) was used to study content and distribution of brain water, and immunohistochemistry was used to examine glial fibrillary acidic-protein (GFAP), astrocyte marker, and myelin basic protein (MBP), oligodendrocyte and myelin marker. Results In the intermittent recurrent hyponatremia model, mild and transient hyponatremia was induced (baseline Nap 136.50±1.73mEq/L vs 4h post-medication 129.44±1.20mEq/L, p&amp;lt;0.001), which was recovered 24h after treatment (141.25±0.96mEq/L, NS compared to baseline). However, this situation was repeated over a 7 day period. This translated into a lower ADC value in the whole brain (WB) compared to chow fed animals (25.07±1.71 vs 26.71±2.40*10−3mm2/s, p = 0.05) after this 7 day period, suggesting an increase in total brain water in this situation. There was also an increase in GFAP expression in the gray matter (GM) compared to chow fed animals (33.22±5.25 vs 25.07±2.31au, p = 0.031), although no significant changes in MBP’s expression were seen. Acute on intermittent recurrent hyponatremia induced hypotonic hyponatremia (116.00±1.16mEq/L, p&amp;lt;0.001 compared to baseline). In this situation, a progressive decrease in ADC values in the WB was seen, and it was less pronounced compared to chow fed animals (slope -0.11±0.02 vs -0.26±0.006, p = 0.014). When GM and white matter (WM) were analysed separately, they both showed a progressive increase in ADC values, more evident in the WM (slope WM 0.19±0.04, p&amp;lt;0.05; slope GM 0.05±0.02, p = 0.002). The water overload increased GFAP and MBP’s expression in the WM (GFAP 23.17±6.37 vs 16.83±5.17au, p = 0.001; MBP 45.20±8.32 vs 28.76±7.03au, p&amp;lt;0.001), but no changes were seen in the GM, similarly to what had been observed in the acute hyponatremia model. Conclusion Intermittent recurrent hyponatremia is a novel animal model that suggests there can be significant water retention after only a few hours of hyponatremia a day, provided this situation is repeated over time. Such water retention translates into greater brain water accumulation and astroglial activation in the GM. These animals's response to an additional water overload does not show big variations compared to what is observed in acute hyponatremia. This study highlights the importance of slight fluctuations in natremia, which, if maintained over time, can translate underlying water retention with consequences at the central nervous system level.

"Sack of Marbles" Appearance of a Scalp Teratoma.

HomeRadiologyVol. 307, No. 5 PreviousNext Reviews and CommentaryFree AccessImages in Radiology“Sack of Marbles” Appearance of a Scalp TeratomaSumit Thakar , Pavan VasoyaSumit Thakar , Pavan VasoyaAuthor AffiliationsFrom the Department of Neurosurgery, Sri Sathya Sai Institute of Higher Medical Sciences, ITPL Rd, EPIP Area, Whitefield, Bangalore 560066, India.Address correspondence to S.T. (email: [email protected]).Sumit Thakar Pavan VasoyaPublished Online:May 30 2023https://doi.org/10.1148/radiol.230033MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In A 52-year-old woman presented with a painless, gradually enlarging scalp swelling that had been present since childhood. At examination, there was a 15 × 10 × 12–cm mass in the parieto-occipital region. MRI scan showed a large cystic lesion in the subgaleal plane of the scalp. It was hypointense with T1-weighted images and hyperintense with T2-weighted images and contained multiple nodules of varying sizes floating in the cyst, giving it a “sack of marbles” appearance (Figure). The nodules had thick outer rims that were iso- to hyperintense with T1-weighted sequences and hypointense with T2-weighted sequences and thin inner cores that were hypointense with T1-weighted sequences and hyperintense with T2-weighted sequences. The nodules demonstrated restricted diffusion (Figure) and had low apparent diffusion coefficient values. After completing surgical excision, the cyst was found to contain sebum-like material, hard spherules, and multiple strands of hair (Figure). Histopathologic examination confirmed the diagnosis of a mature cystic teratoma, with elements from all three germ layers. There was no recurrence after 6 months of follow-up.Images in a 52-year-old woman presenting with a scalp mass show a large cystic lesion in the subgaleal plane of the scalp with a “sack of marbles” appearance. (A) Sagittal unenhanced T1-weighted MRI scan shows a smooth-walled hypointense cyst with multiple spherical nodules that had isointense to hyperintense rims and thin hypointense cores. (B) Diffusion MRI scan shows the nodules demonstrating restricted diffusion. (C) Photograph of the gross specimen shows a sebum-like material within the cyst, hard spherical nodules, and strands of hair.Download as PowerPointOpen in Image Viewer Mature cystic teratomas are commonly found in the gonadal tissues and in the head and neck region. In the head, they have a predilection for the orbit and scalp. The “marbles” are spherical aggregates of keratin, fat, sebaceous material, fibrin, and hair floating within the fluid matrix of the cyst. Though uncommon, the “sack of marbles” sign is considered pathognomonic of mature cystic teratomas in the head and neck (1–3).Disclosures of conflicts of interest: S.T. No relevant relationships. P.V. No relevant relationships.

Diffusion restriction associated with bevacizumab treatment in recurrent glial tumors, evaluation of survival with ADC measurement analysis.

Recurrent glial tumors treated with bevacizumab often develop diffusion restriction. In this study, we investigated the diffusion restriction pattern after bevacizumab treatment along with the relationship between apparent diffusion coefficient (ADC) values of regions with diffusion restriction and survival period as there are conflicting results on this relationship. We retrospectively identified 24 patients treated with bevacizumab for recurrent glial tumor who had low ADC values after the onset of the treatment. Magnetic resonance imaging (MRI) findings were analyzed for the presence of restricted diffusion, time to onset, location, duration of restriction, and persistence of restriction after cessation of bevacizumab treatment. A retrospective study was performed to investigate the relationship between ADC values obtained at first post-bevacizumab scan and survival periods. Diffusion restriction appeared 2 to 6 months after the onset of bevacizumab therapy and persisted up to 24 months while on bevacizumab. The restricted diffusion persisted up to 6 months after cessation of bevacizumab. Our results showed that there is a negative correlation between ADC values and progression free survival as well as overall survival. Patients having diffusion restriction areas with lower ADC values after the initiation of bevacizumab treatment, are found to have increased overall and progression free survival (p<0.05). In patients with recurrent glial tumor treated with bevacizumab, diffusion restriction can be observed and the ADC values obtained from these areas at first post-bevacizumab MRI scan correlate with progression free and overall survival with the worst survival seen in patients with higher ADC values which therefore can be considered as an imaging marker that can predict the prognosis.

MRI Staging of Anorectal Malignancy—A Reporting Dilemma: Is It Adenocarcinoma or Squamous Cell Carcinoma?

Abstract Aim Magnetic resonance imaging (MRI) of anorectal malignancy is often reported assuming low rectal adenocarcinoma (LRC). The biopsy may, however, reveal squamous cell carcinoma (SCC). Thus, the aim was to compare the imaging findings of SCC and LRC. Methods This was a retrospective study of patients who underwent staging MRI for anorectal malignancy (&lt;5 cm from the anal verge) for adenocarcinoma or squamous cell carcinoma between 2016 and 2021. Two radiologists blinded to biopsy reviewed MRI. Imaging findings and apparent diffusion coefficient (ADC) values were compared between SCC and LRC. Results We studied 137 patients (n = 60 SCC, n = 77 LRC) with a mean age of 50.4 (standard deviation: 12.4) years and tumor length of 5.6 ± 1.9 cm. SCC patients were older, and their distal tumor margin was closer to the anal verge (5.3 vs. 22 mm for LRC; p &lt;0.001). T2 intermediate signal and diffusion restriction was seen in 97 and 98.2% of SCC and 75.3 and 77% of LRC, respectively. SCC had lower ADC values (0.910 × 10−3 mm2/s) than LRC (1.126 × 10−3 mm2/s; p &lt; 0.001). But there was no difference in the ADC values when T2 hyperintense tumors were excluded (p = 0.132). Extramural vascular invasion (EMVI) was more frequent in LRC (35.1 vs. 16.7%; p = 0.013). A combination of distance from the anal verge of less than 11 mm, absent EMVI, and the presence of internal iliac and inguinal nodes had an area under the curve (95% confidence interval) of 0.810 (0.737–0.884). Conclusion ADC values are unhelpful in differentiating SCC and LRC. Tumors closer to anal verge, absence of EMVI, and the presence of inguinal and internal-iliac nodes may point towards SCC.

The impact of the apparent diffusion coefficient for the early prediction of the treatment response after definitive radiotherapy in prostate cancer patients

PurposeWe assessed early changes in apparent diffusion coefficient (ADC) and serum prostate specific antigen (PSA) values after definitive radiotherapy (RT) without androgen deprivation treatment in low- and intermediate-risk prostate cancer (PC) patients. Materials and MethodsThe clinical data and ADC parameters of 229 PC patients were retrospectively evaluated. Pre-treatment and post-treatment serum PSA and primary tumor ADC values were calculated. Post-treatment DW-MRI was performed median 4.1 months after completion of definitive RT. The prognostic factors predicting freedom from biochemical failure (FFBF) and progression-free survival (PFS) were analyzed using univariable and multivariable analyses. ResultsWith a median follow-up time of 80.8 months, the 5-year FFBF and PFS rates were 95.9% and 89.3%, respectively. Eleven patients (4.8%) had PSA relapse, with a median of 34.4 months after the completion of RT. A statistically significant difference in post-treatment ADC values was noted between patients with and without recurrence (0.94 ± 0.07 vs. 1.10 ± 0.20 × 10-3 mm2/sec; p< 0.001). Patients with a Gleason score (GS) of 6 and low-risk disease had significantly higher post-treatment tumor ADC and PSA levels than patients with a GS of 7 and intermediate-risk disease. The 5-year FFBF rate in patients with tumor ADC ≤ 0.96 × 10-3 mm2/sec was significantly lower than patients with tumor ADC > 0.96 × 10-3 mm2/sec (85.5% vs. 100; p< 0.001). In the multivariable analysis, a lower ADC value, GS 4 + 3 and intermediate-risk disease were independent predictors of worse FFBF. In the multivariate analysis, a lower post-treatment ADC value and a GS of 4 + 3 were significant prognostic factors for a lower PFS. ConclusionThese findings suggest that the post-treatment tumor ADC value could be used for early treatment response evaluation after definitive RT in PC patients.

Diagnostic Accuracy of Apparent Diffusion Coefficient Value in Differentiating Benign and Malignant Brain Lesions Keeping Histopathology as Gold Standard

Objective: The purpose of this study was to assess the competence of preoperative Apparent Diffusion Coefficient (ADC) values in predicting brain tumors as benign or malignant, keeping histopathology as the gold standard.Study Design: Cross-sectional study.Place and Duration of Study: The study was carried out at the Department of Diagnostic Radiology, POF Hospital, Wah Cantt, Pakistan, from December 12th 2020 to June 9th 2021.Materials and Methods: The apparent diffusion coefficient (ADC) sequence is based on the diffusion properties of water molecules within tissues and correlates with tissue cellularity. ADC may have a role in predicting tumor grade for gliomas and may in turn, assist in identifying tumor biopsy sites.A total of 140 patients were enrolled in the study. In all the images, the slice thickness was taken as 3mm, and the slice gap of 10. The mean age of the patients was 46.5±14.0 years. Males were predominant. The mean BMI was 26.8±5.5 kg/m2, and the mean duration of symptoms was 2.0±1.4 months.Results: The mean age of the patients enrolled in the study was 46.5±14.0 years. Males were predominant; there were 85 males (60.7%) and 55 females (39.3%). The mean duration of symptoms was 2.0±1.4 months. A history of chronic headache was found in 100 patients (71.4%), a history of seizures in 20 (14.3%), and a history of focal deficit was present in 111 patients (79.3%). Apparent diffusion coefficient (ADC) value in differentiating benign and malignant brain lesions showed sensitivity 77.5%, specificity 91.6%, PPV 92.5%, NPV 75.3% and diagnostic accuracy 83.5%.Conclusion: Overall, malignant brain lesions display lower ADC values than benign ones. Apparent diffusion coefficient (ADC) values improved our abilities to differentiate benign from malignant brain lesions.

Predicting of Ki-67 Expression Level Using Diffusion-Weighted and Synthetic Magnetic Resonance Imaging in Invasive Ductal Breast Cancer.

To investigate the association between quantitative parameters generated using synthetic magnetic resonance imaging (SyMRI) and diffusion-weighted imaging (DWI) and Ki-67 expression level in patients with invasive ductal breast cancer (IDC). We retrospectively reviewed the records of patients with IDC who underwent SyMRI and DWI before treatment. Precontrast and postcontrast relaxation times (T1, longitudinal; T2, transverse), proton density (PD) parameters, and apparent diffusion coefficient (ADC) values were measured in breast lesions. Univariate and multivariate regression analyses were performed to screen for statistically significant variables to differentiate the high (≥30%) and low (<30%) Ki-67 expression groups. Their performance was evaluated by receiver operating characteristic (ROC) curve analysis. We analyzed 97 patients. Multivariate regression analysis revealed that the high Ki-67 expression group (n = 57) had significantly higher parameters generated using SyMRI (pre-T1, p=0.001) and lower ADC values (p=0.036) compared with the low Ki-67 expression group (n = 40). Pre-T1 showed the best diagnostic performance for predicting the Ki-67 expression level in patients with invasive ductal breast cancer (areas under the ROC curve (AUC), 0.711; 95% confidence interval (CI), 0.609-0.813). Pre-T1 could be used to predict the pretreatment Ki-67 expression level in invasive ductal breast cancer.

How can we differentiate supratentorial tumor recurrence from postradiation imaging changes in children treated for primary malignant brain tumors?

Distinguishing tumor recurrence from therapy-induced imaging changes (TIIC) on brain MRI in children treated for primary malignant brain tumors may be challenging. The authors aimed to assess the diagnostic ability of multimodal MRI in differentiating TIIC from tumor recurrence. The authors retrospectively included children with abnormal supratentorial brain MRI findings after treatment for primary malignant brain tumors (regardless of their localization) with complete resection and radiotherapy. A total of 18 patients with TIIC and 25 patients with tumor recurrence were compared, according to structural, apparent diffusion coefficient (ADC), and arterial spin labeling (ASL) imaging data accrued over time. TIIC were defined by a new MRI scan that was stable for at least 1 year or had regressed, or by histopathology findings in specimens obtained when the anomaly was surgically treated. The time interval between completion of radiotherapy and the appearance of abnormal brain MRI findings was significantly shorter in the TIIC group compared with the tumor recurrence group (median 6 vs 35 months; p < 0.001). TIIC appeared as foci of increased T2-weighted signal intensity, without nodule, associated with variable contrast enhancement. Tumor recurrence appeared as a well-defined nodule with intermediate signal intensity on T2-weighted images with nodular contrast enhancement. Relative ADC values were significantly higher in the TIIC group (median 1.43 vs 0.88; p < 0.001). Relative ASL-cerebral blood flow (CBF) values were significantly lower in the TIIC group (median 0.27 vs 0.43; p = 0.04). On follow-up MRI, TIIC could progress, regress, or remain stable. In most instances (72%), they decreased in size or remained stable at 4 years of follow-up. MRI features of TIIC include foci of increased signal intensity without a demonstrable nodule on T2-weighted images, high ADC values, and lower ASL-CBF values, whereas tumor recurrence appears as a well-defined nodule with low ADC values and higher ASL-CBF values.

Acute pancreatitis after pancreatoduodenectomy: A prospective study of diffusion-weighted magnetic resonance imaging, serum biomarkers, and clinical features

BackgroundPostpancreatectomy acute pancreatitis is challenging to diagnose and poorly characterized in its early phases. However, it represents the ideal target for novel therapeutic opportunities possibly gleaned from medical acute pancreatitis. This study aims to systematically investigate early radiologic, biochemical, and clinical features of postpancreatectomy acute pancreatitis. MethodsThis was a prospective observational study of patients undergoing pancreatoduodenectomy from September 2019 to January 2021. Diffusion-weighted magnetic resonance imaging was performed on postoperative day 3. Serum pancreatic amylase and lipase were assessed daily until postoperative day 5. Postoperative serum hyperamylasemia and postpancreatectomy acute pancreatitis were defined based on the International Study Group for Pancreatic Surgery definition. ResultsA total of 65 patients were enrolled according to the sample size calculation. Patients with postoperative serum hyperamylasemia and postpancreatectomy acute pancreatitis had significantly lower apparent diffusion coefficient values at diffusion-weighted magnetic resonance imaging but no macroscopic features consistent with acute pancreatitis. Subsequently, 21 patients (32.3%) underwent computed tomography imaging for clinical worsening, and 6 had radiologic features of acute pancreatitis. All these latter patients had postoperative serum hyperamylasemia and worse outcomes, characterized by local (postoperative pancreatic fistula: 83%) and systemic morbidity (sepsis: 66.7%). The postoperative serum hyperamylasemia incidence was 21.5% (n = 14), and postpancreatectomy acute pancreatitis occurred in 6 patients (9.2%), with 4 grade B (6.1%) and 2 grade C (3%). ConclusionPostpancreatectomy acute pancreatitis is characterized by early serum hyperamylasemia and hyperlipasemia. Although pancreatic changes may appear at postoperative day 3 diffusion-weighted magnetic resonance imaging, its standard use has no impact on postoperative management. Macroscopic radiologic features appear later and correlate with worse clinical scenarios. This paper paves the ground for including postpancreatectomy acute pancreatitis in the spectrum of acute pancreatitis, promoting the transfer of treatment strategies for acute pancreatitis into managing postpancreatectomy acute pancreatitis.

The investigation of reduced field-of-view diffusion-weighted imaging (DWI) in patients with nasopharyngeal carcinoma: comparison with conventional DWI

Field-of-view optimized and constrained undistorted single-shot imaging (FOCUS) is a new sequence that shows enhanced anatomical details, improving the diffusion-weighted (DW) images. To investigate the value of FOCUS diffusion-weighted imaging (DWI) in the evaluation of nasopharyngeal carcinoma (NPC) and compare it with the single-shot echo planner imaging (SS-EPI) DWI approach. A total of 87 patients with NPC underwent magnetic resonance imaging, including FOCUS and SS-EPI DWI sequences. The signal-to-noise ratio (SNR), signal-intensity ratio (SIR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) values of the nasopharyngeal lesions were measured and compared. According to the clinical stages of patients, T and N were divided into early and advanced stage groups, respectively. The mean ADC values of the two techniques were computed, and the area under the curve (AUC) was estimated to calculate the diagnostic efficiency. Subjective and objective image qualitative values of FOCUS were significantly higher than those of SS-EPI. The ADC values for FOCUS of early T and N stages were significantly lower than those of the advanced stages. FOCUS provides significantly better image quality in NPC compared to SS-EPI, with lower ADC values for early-stage disease than late-stage disease.

Does the apparent diffusion coefficient from diffusion-weighted MRI imaging aid in the characterization of malignant soft tissue tumors and sarcomas.

To identify trends in apparent diffusion coefficient (ADC) measurements from diffusion-weighted imaging (DWI) with respect to tumor type classification and other tumor characteristics whether common malignant soft tissue tumors can be distinguished. A consecutive series of extremity malignant soft tissue tumors and soft tissue sarcomas (STS) among 78 adult patients with conventional MRI and DWI were included. Each case was evaluated with respect to T1/T2 signal alterations and heterogeneity, presence of peritumoral edema, necrosis, cystic changes, internal hemorrhage, and maximum longitudinal dimension blinded to the histology. The ADC mean and minimum were obtained using a free-hand region of interest of the whole tumor and the darkest (lowest signal area) ADC area of the tumor. Kruskal-Wallis and Wilcoxon Rank-Sum Tests were used to determine associations and significance between tumor subtypes. Intraclass correlation (ICC) and kappa calculations were utilized to assess inter-reader agreements for ADC values and reader diagnosis. Liposarcomas showed more heterogenous T1W images with hyperintense T1W signal when compared to tumors not classified as liposarcoma (P = 0.046 and P = 0.010, respectively). Liposarcomas were relatively consistent in demonstrating an absence of hemorrhage (81.8%) while undifferentiated pleomorphic sarcomas consistently showed intralesional hemorrhage (90%). When comparing individual tumor classifications against the rest of the samples, lymphomas registered lower mean and minimum ADC values in the whole tumor and in themost hypointense area of the tumor for both readers (P < 0.05). The interobserver agreement between the two readers was good to excellent for all four ADC measurements (ICC = 0.65-0.98). Diffusion-weighted imaging generated ADC measurements are reproducible but currently offer limited insight in being able to differentiate among different malignant soft tissue tumor and sarcoma histologies.T1W and T2W signal characteristics also offer limited insight indifferentiating between soft tissue malignancies.

Prognostic Factors of Pretreatment Magnetic Resonance Imaging for Predicting Clinical Outcome in Patients With Parotid Gland Cancer.

This study aimed to assess the utility of pretreatment magnetic resonance imaging (MRI) in predicting the clinical outcomes of patients with parotid gland cancer. A total of 43 patients with histopathologically confirmed primary parotid gland cancer, who underwent pretreatment MRI, were enrolled in this study. All images were retrospectively reviewed, and MRI features were evaluated as possible prognostic factors influencing the progression-free survival (PFS) using the Kaplan-Meier method and Cox proportional hazards regression model. Cox regression analysis was used to estimate the hazard ratios (HRs) with 95% confidence interval (95% CI) values. Kaplan-Meier survival analysis showed that old age (>73 years, P < 0.01), large maximum tumor diameter (>33 mm, P < 0.01), low apparent diffusion coefficient value (≤1.29 ×10 -3 mm 2 /s, P < 0.01), ill-defined margin ( P < 0.01), skin invasion ( P < 0.01), regional nodal metastasis ( P < 0.01), heterogeneous enhancement ( P < 0.05), and high signal intensity ratio on gadolinium-enhanced fat-suppressed T1-weighted images (>2.017, P < 0.05) were significant predictors of worse PFS. Cox proportional hazards regression analysis revealed that regional nodal metastasis (HR, 32.02; 95% CI, 6.42-159.84; P < 0.01) and maximum tumor diameter (HR, 1.04; 95% CI, 1.01-1.08; P < 0.05) were independent predictors of PFS. Pretreatment MRI parameters could be prognostic factors of patients with parotid gland cancer. In particular, the maximum tumor diameter and regional nodal metastasis, which were closely associated with T and N classifications, were important prognostic factors in predicting the PFS.

Optic nerve head diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient values as measuring tools for papilledema grade in idiopathic intracranial hypertension

Aim The aim of this study was to explore if there is a relationship between the grade of papilledema and MRI diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) values of the optic nerve head (ONH) in patients having idiopathic intracranial hypertension (IIH). Patients and methods This is a prospective study that was conducted between March 2020 and June 2022 on 285 patients diagnosed as having IIH, who were subjected to meticulous clinical examination, visual field testing, color vision testing, and orbital MRI done within one week of diagnosis. ONH signal intensity was graded and then compared with papilledema grade, and the results were analyzed. Results The study included 285 patients (156 females and 129 males), with a mean age of 30.8±9.6 years, definitely diagnosed as having IIH with lumbar puncture opening pressure ranging from 18 to 58 cmH2O (mean=35.6±9.8 cmH2O). The papilledema grades were grade I (121 patients), grade II (136 patients), grade III (21 patients), and grade IV (seven patients). ADC values of the ONH were found to be gradually decreased with higher papilledema grades among cases. In addition, according to papilledema grading, in grade I, 67% of the patients showed no DWI changes, whereas in grade II, 97% of the patients showed DWI changes in the ONH. In grades III and IV, all patients showed DWI changes. Conclusion MRI can be considered as a diagnostic tool for papilledema. In addition, low ADC values and diffusion restriction can be used as indicators for the severity of ONH insult in cases of increased intracranial tension.