Diffusion Coefficient Values Research Articles

The apparent diffusion coefficient can serve as a predictor of survival in patients with gliomas

Background and purposeMagnetic resonance imaging is indispensable for the preoperative diagnosis of glioma. This study aimed to investigate the role of the apparent diffusion coefficient values as predictors of survival in patients with gliomas.Methods and materialsA retrospective analysis was conducted on 101 patients with gliomas who underwent surgery between 2015 and 2020. Diffusion-weighted MRI was performed before the surgery. The regions of interest were categorized into parenchymal area, non-enhancing peritumoral area, and necrotic or cystic area. All the patients were divided into three subgroups: the parenchyma group, the non-enhancing peritumoral signal abnormality group, and the necrosis or cyst group. Univariate and multivariate analyses were performed using COX regression.ResultsIn the parenchymal group, Ki67, P53, IDH, and the high or low ADC values were identified as independent prognosticators for disease-free survival, while Ki67, IDH, and the high or low ADC values for overall survival. In the non-enhancing peritumoral signal abnormality group, Ki67, P53, IDH, and the ADC parenchymal area/ADC non−enhancing peritumoral area ratio were identified as independent prognostic factors for disease-free survival, while Ki67, IDH, and the ADC parenchymal area/ADC non−enhancing peritumoral area ratio for overall survival. In the necrosis or cyst group, Ki67 was significantly associated with disease-free survival, while Ki67 and the ADC value of the necrotic or cystic area for overall survival.ConclusionsThe ADC values, including the ADC value in the parenchymal area, the ADC parenchymal area/ADC non−enhancing peritumoral area ratio, and the ADC value in the necrotic or cystic area, can serve as an efficient and potential index for predicting the survival of patients with glioma.

Usefulness of apparent diffusion coefficient values for assessment of MRI abnormality at term equivalent age in low-birth-weight infants weighing less than 1500g.

To determine whether apparent diffusion coefficient (ADC) measurements at term equivalent age (TEA) are useful for assessment of major abnormalities revealed by MRI. Of 405 neonates who underwent MRI during the period 2016-2022, 101 low birth weight (LBW) infants (birth weight < 1500g) were imaged at TEA. ADC values were measured in the thalamus, basal ganglia, anterior and posterior centrum semiovale, pons, and cerebellar hemisphere. The ADC values in LBW infants with and without major abnormalities evident on MRI were compared at the above six sites. Abnormal findings included IVH-3 IVH-4, more than six punctate white matter lesion, white matter injury (cystic or non-cystic), and major cerebellar hemorrhage. LBW infants overall (N = 101) and an extreme LBW (ELBW) group (< 1000g) (N = 55) were compared and area under the curve was calculated using ROC analysis. There were no difference in ADC values between LBW infants with and without major abnormalities. In ELBW infants, ADC values in the cerebellum were higher when major abnormalities were present (p = 0.045). ROC analysis yielded AUC < 0.7 for both LBW cases overall and ELBW cases. For LBW infants overall, ADC measurements alone at TEA are not very useful for differentiation between individuals with and without major abnormalities, but ELBW infants with major abnormalitiesshowed higher ADC values in the cerebellum, suggesting that the normal reduction of ADC occurring with maturation between preterm birth and TEA may be impaired.

Correlation of magnetic resonance imaging and computed tomography with biological factor expression and lymph node metastasis in aggressive prostate cancer.

This paper focused on probing the correlation of magnetic resonance imaging (MRI) and computed tomography (CT) manifestations with biological factor expression and lymph node metastasis (LNM) in aggressive prostate cancer (PCa). A total of 136 PCa patients underwent surgical treatment, and received CT and MRI examinations before surgery, whereby the apparent diffusion coefficient (ADC) values of quantitative MRI (qMRI) parameters were obtained. Patients were categorized into the non-aggressive PCa group and aggressive PCa group according to the postoperative pathological results and Gleason scores. The expression of biological factors [prostate-specific antigen (PSA), proliferating cell nuclear antigen (PCNA), p27, and ki-67] in both groups was tested. CT and MRI manifestations of aggressive PCa patients were analyzed. The qMRI parameters, biological factors levels and LNM were compared in two groups; the relationships between CT and MRI manifestations, qMRI parameters and positive expression of biological factors and LNM were probed in two groups. In the aggressive PCa group, MRI and CT presented different degrees of abnormal prostate changes. In the aggressive PCa group, PSA and p27 expression and ADC values were lower, and PCNA and ki-67, and LNM rates were higher. Patients' LNM rate was higher than that of ≤ 2 cm when the tumor diameter was &gt; 2 cm. ADC values were positively correlated with PSA and p27 positive expression, and negatively correlated with PCNA, ki-67 and LNM in the aggressive PCa group. MRI and CT manifestations of aggressive PCa had certain characteristics; MRI manifestations and qMRI possessed a correlation with biological factors and LNM; ADC could be employed to assess the aggressiveness of PCa.

Integrating Diffusion-weighted and Perfusion-weighted Imaging for Improved Grading and Characterization of Brain Tumors

Objective: This study aims to evaluate the role of Diffusion-Weighted Imaging (DWI) and Perfusion-Weighted Imaging (PWI) in the detection, characterization, and grading of brain tumors, focusing on their correlation with histopathological findings. Materials and Methods: A total of 40 patients with intracranial mass lesions underwent DWI, PWI, and conventional MRI using a 1.5 Tesla MRI scanner. Apparent Diffusion Coefficient (ADC) values were calculated for tumor core, peritumoral edema, and normal brain tissue. Cerebral Blood Volume (CBV), Cerebral Blood Flow (CBF), and Mean Transit Time (MTT) were analyzed using PWI. Data were statistically analyzed, with a p-value ≤ 0.05 considered significant. Results: The study included 38 neoplastic lesions and 2 tuberculomas. DWI showed distinct ADC values for different tumors, with meningiomas having a mean ADC of 0.84 ± 0.3 × 10⁻³ mm²/s and schwannomas a higher ADC of 2.14 × 10⁻³ mm²/s. PWI revealed elevated relative CBV in high-grade gliomas (mean: 2.1 ± 0.76), while lower rCBV was observed in metastases (mean: 0.5 ± 0.26). Tuberculomas exhibited intermediate perfusion characteristics. Conclusion: DWI and PWI, in conjunction with conventional MRI, enhance the diagnostic accuracy for brain tumors by providing valuable information on tumor cellularity and vascularity. These techniques aid in distinguishing between tumor types, grades, and associated edema, thus improving clinical decision-making and treatment planning.

Magnetic resonance imaging quantitative assessment of corticospinal tract damage in basal ganglia infarction.

To retrospectively explore the role of magnetic resonance imaging (MRI) diffusion tensor imaging (DTI) in analyzing the corticospinal tract injury in acute cerebral anterior circulation infarction in the basal ganglia region and the correlation between DTI parameters and neurological function scores, patients with acute cerebral infarction and stroke had undergone plain MRI and DTI sequence scanning were enrolled. Diffusion tensor tractography was used to perform 3-dimensional reconstruction of bilateral corticospinal tracts (CST). The image data were processed to obtain fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values, and the correlation between the DTI parameters and neurological function scores of National Institutes of Health Stroke Scale (NIHSS) was evaluated. A total of thirty-two patients with acute ischemic cerebral infarction were retrospectively enrolled, including 19 males and 13 females with a mean age 63.22 ± 7.78 years. The CST score was 0 in 2 (6.25%) patients, 1 in 9 (28.13%), 2 in 9 (28.13%), 3 in 7 (21.88%), and 4 in 5 (15.63%). The FA value significantly (P = .01) decreased (0.52 ± 0.03 vs 0.62 ± 0.04) on the ischemic side compared with that on the normal side. A significant (P < .05) difference was detected in the number of nerve fibers (223.3 ± 110.0 vs 246.7 ± 104.4) rather than in the ADC values (0.86 ± 0.06 vs 0.84 ± 0.06) between the ischemic and healthy sides. The FA and ADC values were not significantly (P > .05) different according to the CST scores 0, 1, 2, 3, or 4 between the ischemic and healthy sides. There was a significant (P < .05) negative correlation between the FA value on the infarcted side and the NIHSS score. In conclusion, with the DTI technology, varying degrees of damage to the corticospinal tract at the infarcted side can be detected and important clinical information can be provided for the diagnosis and prognosis of acute cerebral infarction by evaluating the degree of corticospinal tract injury.

Cystitis glandularis: MR imaging characteristics in 27 patients.

To explore the diagnostic characteristics of cystitis glandularis (CG) using magnetic resonance imaging (MRI). A retrospective study was conducted on pathologically confirmed patients who underwent bladder MRI examination between January 2019 and November 2023. Image analysis was jointly conducted, with emphasis on lesion location, morphology, size, signal intensity, and pattern of enhancement, by two genitourinary radiologists with 22 and 15 years of experience, respectively. A total of 27 patients with 27 lesions were included (median age 47 years, 24 males). The lesions were mostly located in the bladder trigone area (18/27). The lesions could be categorized as focal thickening (17/27), nodular (8/27), and diffuse thickening of the entire bladder (2/27) in morphological terms. On T2-weighted imaging (T2WI), 15 of 17 focal thickening lesions appeared as a slightly hyperintense thickened inner layer, with a higher signal in the center of the thickened inner layer, resembling a sandwich sign, and 6 of 8 nodular lesions were slightly hyperintense. On T1-weighted imaging (T1WI), 19 patients showed slight hypointensity. The lesions on DWI showed mainly high (5/27) and slightly high signal (21/27), with an average mean apparent diffusion coefficient (mADC) value of 2.171 ± 0.052 × 10-3mm2/s. Among the 23 patients who underwent dynamic contrast-enhanced (DCE) scanning, 18 lesions showed mild enhancement in the arterial phase (average 1.7 times comparing to unenhanced phase), and the degree of enhancement gradually increased in the venous and delayed phases (average 2.2 and 2.3 times compared to the unenhanced phase, respectively), showing a progressive enhancement pattern. On MRI, the majority of CG manifest as focal thickening or nodules in the bladder trigone area, showing slight hyperintensity on T2WI, slight hypointensity on T1WI, and a progressive enhancement pattern, without significant restriction on DWI. Focal thickening lesions may exhibit a special sandwich sign.

Multiparametric quantitative MRI of healthy adult pancreas: correlations with gender and age

BackgroundThe pancreas plays an important role in the nutrition and metabolism of the whole body. Many disease processes including obesity, diabetes mellitus (DM), acute or chronic pancreatitis, and pancreatic carcinoma result in abnormality of pancreas morphology and function. Magnetic resonance imaging (MRI) provides quantitative parameters including T1, T2, and apparent diffusion coefficient (ADC) values for evaluating normal and abnormal pancreas. Based on the normal range of these quantitative parameters, pancreatic abnormality could be detected early. However, the range and the relationship of T1, T2, and ADC values with gender and age groups using the same dataset have not been explored.PurposeTo establish the ranges of MRI tissue and functional parameters, including T1, T2, and ADC values, in healthy adult pancreas and their correlations with gender, subregion, and age.Materials and methodsThe T1, T2, and ADC values of healthy pancreas in 86 adults were measured using a 3.0-T MRI scanner. The average T1, T2, and ADC values were obtained in the whole pancreas and subregions (head, neck, body, and tail). Their correlations with gender and age were investigated.ResultsThe T1, T2, and ADC values of the whole pancreas from all subjects were 870.07 ± 61.86 ms, 44.07 ± 6.14 ms, and 1.072 ± 0.212 × 10−3 mm2/s, respectively. T2 values were significantly different between genders (P &amp;lt; 0.05). No significant differences were found between subregions. The T1, T2, and ADC values differed significantly among the age groups (P &amp;lt; 0.05). The T1 value revealed a moderately positive correlation, while the T2 and ADC values displayed negative correlations with age (r = 0.31, −0.45, and −0.39, respectively). The combination of T1, T2, and ADC values achieved the highest AUC value and showed a significant difference compared to T1, T2, and ADC values alone in predicting age older than 45 years.ConclusionThis study established the normal ranges of T1, T2, and ADC. We found that T2 is different between men and women, and T1, T2, and ADC are age-dependent. These results could be useful for quantitative MRI of pancreatic disease.

Siglec-15 expression in diffuse gliomas and its correlation with MRI morphologic features and apparent diffusion coefficient.

Sialic acid-binding immunoglobulin-like lectin 15 (Siglec-15) enhances tumor immune escape and leads to tumor growth. To investigate the expression of Siglec-15 in diffuse gliomas and its correlation with tumor magnetic resonance imaging (MRI) features. This study included 57 patients with gliomas. Morphological MRI features, including the largest tumor diameter, enhancement category, location, calcification, cysts, and hemorrhage, were visually rated. Apparent diffusion coefficient (ADC) values were calculated in tumor region. MRI morphologic features and ADC were compared between patients with positive and negative Siglec-15 expression. Receiver operating characteristic (ROC) curves were further constructed to assess the diagnostic performance. Siglec-15 was expressed in immunocytes, such as macrophages in the peritumoral area. Siglec-15 expression was positive in 20/57 (35.09%) patients, with higher expression in patients with IDH-mutant gliomas and lower grade gliomas. The tumor diameter was significantly smaller in patients with positive Siglec-15 expression than in those with negative expression for all patients (P = 0.017) and for patients with IDH-mutant gliomas (P = 0.020). Moreover, ADC values of the tumor were significantly higher in patients with positive Siglec-15 expression than in those with negative expression for all patients (P = 0.027). The areas under the ROC curve (AUCs) of the diameter and ADC were 0.702 and 0.686, respectively. A combination of these two parameters generated an improved AUC of 0.762. Siglec-15 was expressed in immunocytes such as macrophages in the peritumoral area, with a positive rate of 35.09%. Positive Siglec-15 expression in diffuse gliomas was correlated with smaller tumor size and higher ADC values.

Magnetic resonance imaging and tractography of sensorimotor tracts in fetuses with intraventricular hemorrhage: feasibility and added prognostic value.

To assess the feasibility, characteristics and prognostic value of prenatal visualization of the corticospinal tracts (CSTs) using diffusion-weighted magnetic resonance imaging (MRI)-based tractography in fetuses with intraventricular hemorrhage (IVH). This was a retrospective single-center cohort study of singleton fetuses diagnosed with IVH on MRI from January 2011 to December 2018. The left and right CSTs were reconstructed according to an in-utero diffusion tensor imaging sequence using a multi-region of interest (ROI) deterministic tractography approach. The CSTs were segmented by two polygonal ROI: at the level of the posterior limb of the internal capsule and the crus cerebri. The morphology and integrity of the CSTs were assessed visually. Internal capsule and crus cerebri apparent diffusion coefficient and fractional anisotropy values were measured. Postnatal motor function data were obtained from the parents using the functional status scale. A total of 35 fetuses with IVH (mean gestational age, 29.1 ± 5.1 (range, 19.9-38.9) weeks) were included in the analysis. Parenchymal involvement on T2-weighted sequences was demonstrated in 19(54%) of the cohort. CST involvement correlated significantly with the presence of parenchymal damage on T2-weighted imaging (P = 0.02). Among liveborn cases, the rate of motor impairment was 14% (1/7) in children with intact CSTs compared with 100% (5/5) in cases in which the CSTs were impaired (P = 0.015). Fetal corticospinal tractography is feasible technically and offers valuable prognostic information. It enhances parental counseling by providing insights into potential motor outcome, underscoring its utility in complementing fetal neurosonography in cases of prenatal IVH. © 2024 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Diffusion tensor imaging of vastus lateralis in patients with inflammatory myopathies.

Inflammation in patients with myositis would increase diffusion of water molecules across sarcolemma that could be detected with the help of diffusion tensor imaging (DTI). We aimed to determine an association between DTI of vastus lateralis (VL) and histopathological findings in cases of myositis and to estimate diagnostic performance of different MRI variables in predicting histopathological outcomes. This prospective cross-sectional observational study included 43 patients with myositis. MRI of bilateral thighs with DWI/DTI protocol was performed in all the patients. Thirty-three patients further underwent biopsy of right VL muscle. Imaging analysis included grading of "Muscle oedema" based on signal intensity (SI) and extent and "fatty infiltration" based on extent on conventional sequences and, acquiring DWI and DTI parameters. Gold standard method to determine inflammation in muscles was histopathological examination. Comparison of DTI/DWI variables with clinical and histopathological variables was done. The average DWI apparent diffusion coefficient (ADC) and DTI ADC values in the patients were 1.77 ± 0.35 and 2.06 ± 0.35 respectively. The average functional anisotropy (FA) was 0.39 ± 0.17 and, the 3 eigenvalues in the patients were 2.96 ± 0.63, 2.05 ± 0.32, and 1.20 ± 0.39 respectively. VL oedema SI weighted score was the best parameter for predicting effaced fascicular architecture and marked lymphocytic inflammation in endomysium on histopathology. VL fatty infiltration weighted score was the best parameter in predicting perifascicular atrophy. Addition of DWI or DTI didn't add significantly in determining active inflammation in cases of myositis.

Diffusion-Weighted MRI Over Standard MRI for Differential Diagnosis between Mucopyocele and Mucoceles.

To determine the accuracy of conventional and diffusion-weighted (DWI) MRI for the differential diagnosis between mucopyocele and mucocele using surgical diagnosis as a reference. This retrospective study included patients referred to our institution between March 2017 and February 2024 for paranasal sinus MRI to characterize an expansile non-enhanced sinus filling on CT. The T1 and T2 signal intensities were recorded, as well as the presence of restriction diffusion, of the penumbra sign, the double rim sign, and the presence of parietal micro-abscesses. Quantitative apparent diffusion coefficient values were also recorded. The study included 74 patients aged 18 to 88 years (mean age: 60.4 ± 17.7 years). Of these, 43 had a mucopyocele and 31 had a mucocele. The T1 high signal intensity was different amongst groups as an hypersignal was present in 35.5% of mucoceles and only 4.7% of mucopyoceles (p = 0.02). The T2 signal did not differ between the two groups (p = 0.59). The double rim sign and the presence of parietal micro-abscesses demonstrated 96.8% and 100% specificities, respectively, but were predominantly located in the maxillary sinus. The penumbra sign exhibited a sensitivity of 60.5% and a specificity of 67.7%. All mucopyoceles exhibited a diffusion restriction with an apparent diffusion coefficient of less than 0.78 × 10-3 mm2/s. DWI is the most useful MRI tool for the accurate differential diagnosis between mucopyocele and mucocele in non-enhanced sinus fillings. III (case-control study) Laryngoscope, 2024.

The Prediction of Radiation-Induced Trismus by the Apparent Diffusion Coefficient Values of Masseter Muscles before Chemoradiotherapy in Locally Advanced Nasopharyngeal Carcinomas.

Although the apparent diffusion coefficient (ADC) value from diffusion-weighted imaging can provide insights into various pathological processes, no studies have examined the relationship between the pre-concurrent chemoradiotherapy (CCRT) mean ADC (ADCmean) values of the masseter muscles and radiation-induced trismus (RIT) in locally advanced nasopharyngeal carcinoma (LA-NPC) patients. Therefore, the current research aimed to investigate the significance of pre-CCRT masseter muscle ADCmean values for predicting the RIT rates in LA-NPC patients treated with definitive CCRT. The pre-CCRT ADCmean values of the masseter muscles and the post-CCRT RIT rates were evaluated. A receiver operating characteristic curve analysis was employed to determine the optimal ADCmean cutoff. The primary objective was to examine the relationship between the pre-CCRT masseter muscle ADCmean values and the post-CCRT RIT rates. Seventy-seven patients were included. The optimal ADCmean cutoff value was 1381.30 × 10-6 mm2/s, which divided the patients into two groups: an ADCmean < 1381.30 × 10-6 mm2/s (n = 49) versus an ADCmean > 1381.30 × 10-6 mm2/s (n = 28). A masseter muscle ADCmean > 1381.30 × 10-6 mm2/s was found to be associated with significantly higher RIT rates than an ADCmean < 1381.30 × 10-6 mm2/s (71.42% vs. 6.12%; p < 0.001). The multivariate analysis results confirmed a pre-CCRT masseter muscle ADCmean > 1381.30 × 10-6 mm2/s as an independent predictor of RIT. Our study presents the first evidence establishing a connection between elevated masseter muscle ADCmean values and higher RIT rates in LA-NPC patients following CCRT. If confirmed with further research, these findings may help to categorize the risk of RIT in these patients.

Measurement of apparent diffusion coefficient (ADC) in fetal organs and placenta using 3 Tesla magnetic resonance imaging (MRI) across gestational ages

Diffusion-weighted imaging (DWI) is a technique used to probe the random microscopic motion of water protons in living tissue, represented by a parameter measurement of apparent diffusion coefficient (ADC) values. This study aimed to measure the ADC values of various fetal organs and placenta using 3T at various gestational ages. This was a prospective observational study. A total of 103 singleton pregnancies from 20 to 38 weeks of gestational age were included. Diffusion-weighted imaging was performed in the axial plane from the fetal head to the trunk with the following parameters: TR: 2000–2500 ms; TE: 88 ms; FOV: 250 mm; 256 matrix; slice thickness: 4 mm with a 0 mm gap; acquisition time: 1 min, 18 s. Diffusion gradient values were b = 0 and b = 700 s/mm2. ADC was measured in fetal brain regions (frontal white matter, occipital white matter, centrum semiovale, pons, thalamus, cerebellum, and fetal organs (lungs, kidney, and placenta). ANOVA was used to calculate the mean ADC values. Karl Pearson’s coefficient of correlation was used to evaluate the correlation between ADC values and increasing gestational age. The mean ADC values of brain regions were: frontal white matter (1.64 ± 0.08 × 10− 3 mm2 /s, F-39.10,p-<0.001), occipital white matter (1.64 ± 0.06 × 10− 3 mm2/s, F-26.14, p-<0.001), centrum semiovale (1.62 ± 0.03 × 10− 3 mm2/s, F-49.88,p-<0.001, pons (1.23 ± 0.09 × 10− 3 mm2/s F-9.14,p-<0.001) ), Thalamus (1.21 ± 0.07 × 10− 3 mm2/s, F-13.54,p-<0.001) and cerebellum (1.36 ± 0.10 × 10− 3 mm2 /s, F-4.19,p-<0.001). The mean ADC values of fetal organs were lung (1.92 ± 0.15 × 10− 3 mm2 /s, F-28.24, p-<0.001), kidney (1.34 ± 0.11 × 10− 3 mm2 /s, F-1.05, p- 0.37) and placenta (1.94 ± 0.11 × 10− 3 mm2 /s, F-160.33, p-<0.001). White-matter regions showed a significant positive correlation with increasing gestational age. Statistically, a negative correlation was observed between increasing gestational age and ADC measurements obtained in the thalamus, cerebellum, pons, and kidney. This will be one of the first few studies to provide the ADC values of the fetal brain and fetal organs using 3T MRI. The current study shows that diffusion-weighted MRI can offer a promising technique to evaluate the structural development of fetal organs and can potentially lead to a biomarker for predicting the functionality of the fetal organs in abnormalities.

MRI-Based Machine Learning for Prediction of Clinical Outcomes in Primary Central Nervous System Lymphoma.

A portion of individuals diagnosed with primary central nervous system lymphomas (PCNSL) may experience early relapse or refractory (R/R) disease following treatment. This research explored the potential of MRI-based radiomics in forecasting R/R cases in PCNSL. Forty-six patients with pathologically confirmed PCNSL diagnosed between January 2008 and December 2020 were included in this study. Only patients who underwent pretreatment brain MRIs and complete postoperative follow-up MRIs were included. Pretreatment contrast-enhanced T1WI, T2WI, and T2 FLAIR imaging were analyzed. A total of 107 radiomic features, including 14 shape-based, 18 first-order statistical, and 75 texture features, were extracted from each sequence. Predictive models were then built using five different machine learning algorithms to predict R/R in PCNSL. Of the included 46 PCNSL patients, 20 (20/46, 43.5%) patients were found to have R/R. In the R/R group, the median scores in predictive models such as support vector machine, k-nearest neighbors, linear discriminant analysis, naïve Bayes, and decision trees were significantly higher, while the apparent diffusion coefficient values were notably lower compared to those without R/R (p < 0.05). The support vector machine model exhibited the highest performance, achieving an overall prediction accuracy of 83%, a precision rate of 80%, and an AUC of 0.78. Additionally, when analyzing tumor progression, patients with elevated support vector machine and naïve Bayes scores demonstrated a significantly reduced progression-free survival (p < 0.05). These findings suggest that preoperative MRI-based radiomics may provide critical insights for treatment strategies in PCNSL.

Correlations between Apparent Diffusion Coefficient (ADC) and Prognosis in Patients with Locally Advanced Rectal Cancer.

the aim of this study is to assess the performance of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) values in predicting the response to neoadjuvant chemoradiation therapy (CRT) and outcome in patients with locally advanced rectal cancer (LARC). ninety-four patients with magnetic resonance imaging (MRI) pre- and post-neoadjuvant treatment were retrospectively enrolled. Three regions of interest (ROIs) were manually drawn on three different slices of the tumor for every DWI sequence. ROIs were positioned to include only high signal areas and avoid artifacts or necrotic areas. ROIs were automatically copied onto the corresponding ADC maps and the system derived three different ADC values, distinguishing between mean, maximum, and minimum values, and the standard deviation (SD). Only mean ADC values were considered. After surgical intervention, pTNM and the Mandard tumor regression grade (TRG) were obtained. Patients with a TRG of 1-2 were classified as responders, while patients with a TRG from 3 to 5 were classified as non-responders. no correlation was found between pre-ADC values and TRG classes, while post-ADC and ΔADC values showed a significant correlation with TRG classes (r = -0.285, p = 0.002 and r = -0.290, p = 0.019, respectively). Post-ADC values were statistically different between responders and non-responders (p = 0.019). When considering the relation between overall survival (OS) and ADC values, pre-ADC showed a negative correlation with OS (r = -0.381, p = 0.001), while a positive correlation was found between ΔADC values and OS (r = 0.323, p = 0.013). According to ΔADC values, the mean OS time between responders and non-responders showed a significant difference (p = 0.030). A statistical difference was found between TRG classes and OS (p = 0.038) and by dividing patients in responders and non-responders (p = 0.019). the pre-ADC and ΔADC values could be used as useful predictors for patient prognosis, thus helping the treatment planning. On the other hand, the post-ADC values, thanks to their relationship with the TRG classes, could be the ideal tool to predict the histopathological response and plan a conservative approach to the treatment of rectal cancer.

Sinonasal adenoid cystic carcinoma: preoperative apparent diffusion coefficient histogram analysis in prediction of prognosis and Ki-67 proliferation status.

To investigate the value of preoperative apparent diffusion coefficient (ADC) histogram analysis in predicting the prognosis of patients with sinonasal adenoid cystic carcinoma (ACC) and the correlation between ADC histogram parameters and Ki-67 labeling index (LI). The study enrolled 66 patients with sinonasal ACC who were surgically resected and confirmed by histopathology. The disease-free survival (DFS) was evaluated with clinical-pathologic and radiologic characteristics using the Cox proportion hazard model. Spearman correlation analysis was used to evaluate the correlation between ADC histogram parameters and Ki-67 LI. The predictive performance of ADC histogram parameters for Ki-67 LI was assessed using the receiver operating characteristic (ROC) curve. Multivariable analysis showed Ki-67 LI (hazard ratio: 9.279; 95% confidence interval 1.099-78.338; P = 0.041) and ADCskewness (hazard ratio: 5.942; 95% confidence interval 1.832-19.268; P = 0.003) were significant independent predictors of DFS. The combination of these two variables achieved the predictive ability with a C-index of 0.717 (95% confidence interval 0.607-0.826). ADCmean and all ADC percentiles (10th, 50th, and 90th) significantly and inversely correlated with Ki-67 LI of ACC (Correlation coefficients = -0.574 to -0.591, Ps < 0.001). Among the ADC histogram parameters, the ADC50th showed superior performance for the differentiation of the high from low Ki-67 LI groups with an area under the curve (AUC) of 0.834 and an accuracy of 80.30%. ADC histogram analysis had predictive value for DFS and Ki-67 LI, which may be a valuable biomarker for prognosis and proliferation status for ACC in clinical practice.

Utility of diffusion-weighted imaging in differentiating benign and malignant breast lesions.

Breast cancer presents a significant global health burden. An accurate differentiation between benign and malignant lesions is imperative for timely intervention. While dynamic contrast enhanced MRI (DCE-MRI) is highly sensitive, its specificity is limited. This has led to the exploration of diffusion-weighted imaging (DWI) in distinguishing between benign and malignant breast lesions. The study aimed to explore the diagnostic utility of DWI in distinguishing between benign and malignant breast lesions. Assessment of 38 breast lesions using DWI with a b value of 800 s/mm2, performed with 3 Tesla MRI. The diagnostic performance of two different region of Interest (ROI) placement approaches was compared to obtain a feasible cut-off value of apparent diffusion coefficient (ADC) to differentiate between malignant and benign lesions. The histopathological reports were used as the gold standard. ADC values of malignant lesions were significantly lower than those of benign lesions (0.84 × 10-3 mm2/s vs. 1.54 × 10-3 mm2/s). The average ADC measured using a small-sized 2D ROI including the darkest part in the ADC map, performed better than the large 2D ROI covering the entire lesion. Using a cut-off value of 0.98 × 10-3 mm2/s, ADC obtained high sensitivity (90%) and specificity (88.9%) in distinguishing between benign and malignant breast lesions. Utilising quantitative analysis of DWI with ADC value measurement, reliably distinguished between benign and malignant breast lesions in this cohort, especially when employing a higher b value of 800 s/mm2.

Comparison of Diffusion-weighted MRI using Singe-Shot Echo-planar Imaging (SS-EPI) and Split Acquisition of Fast Spin Echo Signal (SPLICE) Imaging, a non-EPI technique, in Tumors of the Head and Neck.

Diffusion-weighted imaging (DWI) using single-shot echo planar imaging (DW-EPI) is susceptible to distortions around air-filled cavities and dental fillings, typical for the head and neck area. Non-EPI, Split acquisition of fast spin echo signals for diffusion imaging (DWSPLICE) could reduce these distortions and enhance image quality, thereby potentially improving recurrence assessment in squamous cell carcinoma (SCC) of the head and neck region. This study evaluated whether DW-SPLICE is a viable alternative to DW-EPI through quantitative and qualitative analyses. The DW-SPLICE sequence was incorporated into the standard 3.0T head and neck MRI protocol with DW-EPI. Retrospective analysis was conducted on two subgroups: firstly benign or malignant lesions, and secondly post-treatment SCC recurrence. In both subgroups Image quality and distortion were scored by two independent radiologists, blinded for DW-technique, and evaluated using mixed-effect linear models. Lesion apparent diffusion coefficient (ADC) values were assessed with inter-class correlation (ICC) and Bland-Altman analyses. DWI's delineation geometric similarity to T1-weighted post-contrast (T1Wc) MRI was evaluated using the Dice Similarity Coefficient (DSC) before and after registration. Recurrence in post-treatment SCC scans was evaluated by the same two radiologists blinded for DW-technique. Recurrence detection rates were then compared between DW-SPLICE and DW-EPI using mixed logistic regression at six months and at one-year post-scan follow-up data. From August 2020 to January 2022, 55 benign or malignant lesion scans (55 patients) and 74 post-treatment SCC scans (66 patients) were analyzed. DW-SPLICE scored better on image quality and showed less overall distortion than DW-EPI (0.04<p<0.001). There was high ADC measurement reliability (ICC=0.93, p<0.001), though a proportional bias was also observed (β=0.11, p=0.03), indicating the bias increases as ADC values rise. DWSPLICE exhibited greater geometric similarity to T1Wc before registration (DSC 0.63 vs 0.47, p<0.001) and outperformed DW-EPI by more accurately identifying recurrences after one year (OR=0.96, p=0.05) but not after six months (OR=0.72, p=0.13). DW-SPLICE surpasses DW-EPI on image distortion and quality and improves diagnostic reliability for detecting recurrent or residual SCC on 3T MRI of the HN. Consistent use of one method for follow-up is advised, as ADC values are not completely interchangeable. Integrating DW-SPLICE can significantly improve tumor assessments in clinical practice. ANTs = Advanced Normalization Tools; DSC = Dice Similarity Coefficient; DW-EPI = Diffusion-weighted single-shot echo planar imaging; DW-MS-EPI = Diffusion-weighted multi-shot echo planar imaging; DW-SPLICE = Diffusion-weighted split acquisition of fast spin echo signals for diffusion imaging; DW-TSE = Diffusion-weighted Turbo Spin Echo; ICC = Intraclass Correlation Coefficient; ROC = Receiver Operating Characteristic; SCC = Squamous cell carcinoma; T1WIc = T1 weighted imaging with gadolinium contrast.

Role of Magnetic Resonance Spectroscopy and Diffusion-weighted Imaging in the Evaluation of Supratentorial Brain Tumours with Histopathology Correlation at a Tertiary Care Hospital: An Observational Study

Abstract Background: Traditional magnetic resonance imaging (MRI) may face challenges in accurately discerning supratentorial malignancies. However, advanced techniques such as diffusion-weighted imaging (DWI) and magnetic resonance spectroscopy (MRS) have significantly enhanced diagnostic accuracy. Thus, the study aimed to evaluate the effectiveness of these non-invasive diagnostic methods in patients with suspected intracranial lesions. Materials and Methods: In this prospective observational study at Osmania General and Allied Hospitals, 40 eligible patients were enrolled. After applying the inclusion and exclusion criteria, MRI examinations were conducted at two hospitals utilising GE 1.5T and PHILIPS 1.5T 32-channel machines. Standardised brain sequences, encompassing T1- and T2-weighted scans, DWI, gradient-recalled echo and fluid-attenuated inversion recovery imaging, were systematically performed. In addition, post-contrast administration and contrast-enhanced MRS were employed. Results: In this study, a higher tumour incidence was observed in males (52%) compared to females (48%). The choline/creatine (CHO/Cr) ratio revealed more cases below 1.5 and fewer at the 3.1–3.5 level. Perilesional CHO/Cr ratio had the highest cases (21) at 1.1–2.0 and the lowest (2) at 3.1–4.0. Further analysis revealed significant differences in the mean CHO/Cr ratio amongst primary low-grade (1.8), primary high-grade (3.91) and metastatic tumours (7.23). The mean choline/N-acetyl aspartate (NAA) ratio also differed significantly amongst these tumour types, with choline/NAA and CHO/Cr ratios indicating statistical significance in distinguishing primary low-grade tumours. In addition, mean apparent diffusion coefficient values showed significant differences between primary low-grade tumours (1.1), primary high-grade tumours (0.87) and metastasis (0.855). Conclusion: This study underscores gender-related differences in supratentorial tumour susceptibility and highlights distinct tumour distributions based on grades. These findings emphasise the significance of considering gender, age and histopathological attributes when evaluating supratentorial tumours.

The Significance of Diffusion-Weighted Imaging and Apparent Diffusion Coefficient in the Diagnosis of Early Acute Interstitial Edematous Pancreatitis.

The study assessed the diagnostic value of diffusion-weighted imaging (DWI) and mean apparent diffusion coefficient (ADC) in early acute interstitial edematous pancreatitis (AIEP). Fifty-six AIEP patients and 60 healthy controls underwent an upper abdominal magnetic resonance (MR) examination. The pancreas diameter and ADC values were measured and analyzed across age and gender groups. Results showed that the pancreas diameter varied with sex and age, with smaller diameters in females and the elderly. Mean ADC values were not significantly affected by age or sex. Signal changes were observed in AIEP patients' images, with DWI showing a higher positive rate than T1WI and T2WI. Comparing the control and AIEP groups, the pancreas diameter was significantly larger in AIEP patients, particularly the pancreatic tail in males. ADC values were significantly lower in AIEP patients, and the difference was more pronounced at b=800 s/mm² compared to b=500 s/mm². Mean ADC exhibited good diagnostic potential for early AIEP, with higher sensitivity and specificity values than serum amylase levels. The area under the receiver operating characteristic (ROC) curve (AUC) indicated that the diagnostic value was better at b=800 s/mm² than at b=500 s/mm². In conclusion, the study found that normal pancreas diameter is influenced by sex and age, with smaller diameters in females and the elderly. Mean ADC values were not affected by these factors. Early AIEP could not be diagnosed solely based on pancreas diameter changes. DWI combined with Mean ADC demonstrated high diagnostic value for early AIEP.