rADC Values Research Articles

The Use of Apparent Diffusion Coefficient Values for Differentiating Bevacizumab-Related Cytotoxicity from Tumor Recurrence and Radiation Necrosis in Glioblastoma.

Glioblastomas (GBM) are the most common primary invasive neoplasms of the brain. Distinguishing between lesion recurrence and different types of treatment related changes in patients with GBM remains challenging using conventional MRI imaging techniques. Therefore, accurate and precise differentiation between true progression or pseudoresponse is crucial in deciding on the appropriate course of treatment. This retrospective study investigated the potential of apparent diffusion coefficient (ADC) map values derived from diffusion-weighted imaging (DWI) as a noninvasive method to increase diagnostic accuracy in treatment response. A cohort of 21 glioblastoma patients (mean age: 59.2 ± 11.8, 12 Male, 9 Female) that underwent treatment with bevacizumab were selected. The ADC values were calculated from the DWI images obtained from a standardized brain protocol across 1.5-T and 3-T MRI scanners. Ratios were calculated for rADC values. Lesions were classified as bevacizumab-induced cytotoxicity based on characteristic imaging features (well-defined regions of restricted diffusion with persistent diffusion restriction over the course of weeks without tissue volume loss and absence of contrast enhancement). The rADC value was compared to these values in radiation necrosis and recurrent lesions, which were concluded in our prior study. The nonparametric Wilcoxon signed rank test with p < 0.05 was used for significance. The mean ± SD age of the selected patients was 59.2 ± 11.8. ADC values and corresponding mean rADC values for bevacizumab-induced cytotoxicity were 248.1 ± 67.2 and 0.39 ± 0.10, respectively. These results were compared to the ADC values and corresponding mean rADC values of tumor progression and radiation necrosis. Significant differences between rADC values were observed in all three groups (p < 0.001). Bevacizumab-induced cytotoxicity had statistically significant lower ADC values compared to both tumor recurrence and radiation necrosis. The study demonstrates the potential of ADC values as noninvasive imaging biomarkers for differentiating recurrent glioblastoma from radiation necrosis and bevacizumab-induced cytotoxicity.

The performance of the node reporting and data system 1.0 (Node-RADS) and DWI–MRI in staging patients with cervical carcinoma according to the new FIGO classification (2018)

PurposeTo evaluate the diagnostic accuracy of the Node-RADS score and the utility of apparent diffusion coefficient (ADC) values in predicting metastatic lymph nodes (LNs) involvement in cervical cancer (CC) patients using magnetic resonance imaging (MRI). The applicability of the Node RADS score across three readers with different years of experience in pelvic imaging was also assessed.Material and methodsAmong 140 patients, 68 underwent staging MRI, neoadjuvant chemotherapy and radical surgery, forming the study cohort. Node-RADS scores of the main pelvic stations were retrospectively determined to assess LN metastatic likelihood and compared with the histological findings. Mean ADC, relative ADC (rADC), and correct ADC (cADC) values of LNs classified as Node-RADS ≥ 3 were measured and compared with histological reports, considered as gold standard.ResultsSensitivity, specificity, positive and negative predictive values (PPVs and NPVs), and accuracy were calculated for different Node-RADS thresholds. Node RADS ≥ 3 showed a sensitivity of 92.8% and specificity of 72.5%. Node RADS ≥ 4 yielded a sensitivity of 71.4% and specificity of 100%, while Node RADS 5 yielded 42.9% and 100%, respectively. The diagnostic performance of mean ADC, cADC and rADC values from 78 LNs with Node-RADS score ≥ 3 was assessed, with ADC demonstrating the highest area under the curve (AUC 0.820), compared to cADC and rADC values.ConclusionThe Node-RADS score provides a standardized LNs assessment, enhancing diagnostic accuracy in CC patients. Its ease of use and high inter-observer concordance support its clinical utility. ADC measurement of LNs shows promise as an additional tool for optimizing patient diagnostic evaluation.

Analysis of Diffusion-Weighted and T2-Weighted Imaging in the Prediction of Distinct Granulation Patterns of Somatotroph Adenomas

ObjectiveThe heterogeneity of the somatotroph adenomas, especially for SG and DG subtypes, has attracted great attention in identifying the imaging biomarker of them. The purpose of current study was to compare the diagnostic performance of diffusion-weighted and T2-weighted MRI sequences for preoperatively distinguishing the granulation patterns of somatotroph adenomas. Methods32 patients with clinical diagnosis of somatotroph adenomas from October 2018 to March 2023 were included in this study. Coronal diffusion-weighted imaging (DWI) and T2-weighted MRI sequences data was collected from 3.0T MRI and compared between SG and DG groups. The immunohistochemistry (IHC) was used to confirm the EM pathological subtypes and Ki67 expression levels of somatotroph adenomas postoperatively. ResultsPatients in the SG group had significantly higher signal intensity (SI) ratio of DWI (rDWI) (P<0.001), lower SI ratio of apparent diffusion coefficient (ADC) (rADC) (P<0.001), and higher SI ratio of T2-weighted imaging (rT2) (P=0.011). The combined diagnose index of rDWI and rADC had the highest diagnostic efficiency predicting SG adenomas (sensitivity, 93.3%; specificity, 88.2%; P < 0.001). The rDWI and rADC value had positive and negative correlations with Ki67 index and tumor maximum diameter, respectively. Lower rADC×103 was an independent predictor for SG adenomas. ConclusionsOur results indicated that compared with previously used T2-weighted imaging, the DWI sequence, especially the combined diagnosis index of rDWI and rADC could more efficiently distinguish the granulation patterns of somatotroph adenomas preoperatively.

Evaluations of the diagnostic performance of ZOOMit diffusion-weighted imaging and conventional diffusion-weighted imaging for breast lesions.

Diffusion-weighted imaging (DWI) is valuable in the screening, diagnosis, and grading of breast lesions. However, conventional DWI (C-DWI) is prone to chemical shift and distortion. ZOOMit DWI (Z-DWI), as an advanced magnetic resonance imaging (MRI) technique, applies two spatially selective parallel excitation pulses to focus sampling in the hope of obtaining more valuable information. This study aimed to evaluate and compare the image quality and feasibility of Z-DWI with those of C-DWI in breast lesions. The study included 51 patients with breast lesions who underwent breast MRI from May 2021 to February 2022. All patients received Z-DWI and C-DWI sequences, with b values selected as 50 and 800 s/mm2 (Z-DWIb50, Z-DWIb800, C-DWIb50, and C-DWIb800). Apparent diffusion coefficient (ADC) values based on Z-DWI and C-DWI were calculated. For qualitative analysis, four image quality parameters were selected and assessed on a 4-point Likert scale (1 = poor and 4 = excellent). For quantitative analysis, ADC, relative ADC (rADC), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and tumor-to-parenchymal contrast (TPC) values were selected for comparison. Z-DWI had higher scores compared to C-DWI in terms of lesion conspicuity, anatomical details, distortion and artifacts, and overall image quality (P<0.05). Meanwhile, the agreement between the two readers was reasonably good [intraclass correlation coefficient (ICC) range, 0.360-0.881]. The SNR of Z-DWIb800 was better than that of C-DWIb800 (P<0.001). The Z-DWI ADC and rADC values of breast lesions were statistically significantly lower than those of C-DWI (mean ADC: P<0.001; rADC; P=0.005). Z-DWI sequences were shown to have superior image quality. The ADC map of Z-DWI is more conducive to the imaging evaluation of breast lesions.

Magnetic Resonance Imaging Combined with Histological Techniques for Dynamic Assessment of Cytotoxic Edema after Cerebral Ischemia-Reperfusion Injury.

Reperfusion therapy after ischemic cerebral stroke may cause cerebral ischemia-reperfusion injury (CIRI), and cerebral edema is an important factor that may aggravate CIRI. Our study aimed to dynamically monitor the development of early cytotoxic edema after CIRI by magnetic resonance imaging (MRI) and to validate it using multiple histological imaging methods. Male Sprague Dawley rats were divided into sham and CIRI groups. T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI)-MRI scans were performed in the sham and CIRI groups after reperfusion. Relative apparent diffusion coefficient (rADC) values were calculated and the midline shift (MLS) was measured. A series of histological detection techniques were performed to observe changes in the cerebral cortex and striatum of CIRI rats. Correlation analysis of rADC values with aquaporin-4 (AQP4) and sodium-potassium-chloride cotransport protein 1 (Na+-K+-2Cl-- cotransporter 1; NKCC1) was performed. rADC values began to increase and reached a relatively low value in the cerebral cortex and striatum at 24 h after reperfusion, and the MLS reached relatively high values at 24 h after reperfusion (all p < 0.05). Hematoxylin-eosin (HE) staining showed that the nerve cells in the cortex and striatum of the sham group were regular in morphology and neatly arranged, and in the CIRI-24 h group were irregular, disorganized, and loosely structured. Using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, the number of TUNEL+ cells in the ischemic cortex and striatum in CIRI-24 h group was shown to increase significantly compared with the sham group (p < 0.05). Transmission electron microscopy showed that the perivascular astrocytic foot processes were swollen in the cortex and striatum of the CIRI-24 h group. Pearson correlation analysis demonstrated that rADC values were negatively correlated with the number of anti-glial fibrillary acidic protein (GFAP)+AQP4+ and GFAP+NKCC1+ cells of the CIRI rats. MRI combined with histological techniques can dynamically assess cytotoxic edema after CIRI, in a manner that is clear and intuitive for scientific researchers and clinicians, and provides a scientific basis for the application of MRI techniques for monitoring the dynamic progress of CIRI.

Orbital Lymphoma; A search for MRI predictors of disease extent and treatment response

Background/aims: Lymphoma is the most common orbital malignancy in adults. We aimed to investigate pretreatment MRI predictors of systemic involvement and early therapy response.&#x0D; Material and Method: Histopathologically confirmed orbital lymphoma patients with MRI scans at the time of diagnosis and after treatment constituted the study group. Involvement of lacrimal gland, intraconal and extraconal fat, eyelid, optic nerve and/or optic nerve sheath, extraocular muscles, intraocular involvement and presence of bone destruction were evaluated from pretreatment MR scans by two radiologists. Measurements of ADC values of the mass and pons were collected and the ratio (rADC= lymphoma ADC/ pontine ADC) was calculated. Response to treatment was evaluated from the follow-up MR images. &#x0D; Results: Twenty patients (F/M= 10/10, mean age 57.3 ± 19.7) constituted the study group and histopathologic diagnosis was predominantly B cell lymphoma, extranodal marginal zone lymphoma being the most common (n=12, 60%). The most commonly involved structures were extraconal fat tissue (70%), lacrimal gland (50%) extraocular muscles (40%). Intraconal fat involvement was significantly higher (p=0.017) in patients with systemic disease compared to localized disease. rADC values showed no difference between patients with systemic and localized disease or patients with complete or partial response (p&gt;0.05).&#x0D; Conclusion: Intraconal fat involvement of orbital lymphoma could predict a systemic disease. The predictive value of pretreatment ADC levels should be searched in larger future cohorts.

ROLE OF DIFFUSION-WEIGHTED IMAGING AND APPARENT DIFFUSION COEFFICIENT IN MAGNETIC RESONANCE IMAGING FOR THE EVALUATION OF BRAIN INFARCTION

Cerebral infarction is the leading cause of mortality and morbidity worldwide. The time of diagnosis of cerebral infarction plays a crucial role in the treatment and prognosis of the patient. The intravenous tissue plasminogen activator (tPA) given within three hours after the onset of stroke or early revascularization by percutaneous interventions are the early treatment of choices and has good prognostic value. MRI plays a vital role in the diagnosis of cerebral infarction. A less time-consuming MRI sequence like diffusion with ADC correlation is a highly sensitive imaging technique for early detection. During the early stages of brain infarction which is less than 6 hours after the onset of symptoms, MRI sequences such as T1 and T2 showed no changes. Therefore, DWI and ADC correlation with magnetic resonance imaging plays a vital role improved in the early diagnosis and assessing the prognosis of the patient. The present study is a hospitalbased prospective, cross-sectional study done in 75 patients, who underwent MRI brain evaluation in the department of radiodiagnosis, at Kona Seema institute of medical sciences, for a period of 12 months. Patients who fullled the inclusion and exclusion criteria were selected. ADC and r ADC values are calculated in all patients. The aim of the study is to show that the Apparent Diffusion Coefcient (ADC), diffusion-weighted imaging (DWI) varies with time and space in cerebral infarction and to determine the stage of the infarction using r ADC values, ADC and DWI. In our present study, we proved that the average ADC values and the rADC values change with time and space which helps us to accurately stage the brain infarction in terms of acute, subacute, and chronic cerebral infarction. Combined analysis of DWI with ADC correlation and routine MRI sequences are used for the accurate evaluation of the brain infarction and to assess the progress and treatment plans after brain infarction

Contributional role of susceptibility-weighted imaging and apparent diffusion coefficient in pediatric brain tumor grading

BackgroundCentral nervous system neoplasms are a primary cause of mortality and one of the most frequent solid tumors in children. Magnetic resonance imaging (MRI) plays a key role in the diagnosis and treatment response of pediatric brain tumors as well as providing us with functional information regarding cellularity, metabolism, and neoangiogenesis. This study aimed to evaluate the contributional role of susceptibility-weighted imaging (SWI) and diffusion weight imaging (DWI) in pediatric brain tumor grading by assessing the intratumoral susceptibility signals (ITSS), apparent diffusion coefficient (ADC), and relative ADC (rADC).ResultsA significant correlation was noted between the (ITSS) score and the brain tumor grade (P < 0.001) with a descending trend in the low-grade tumor (ITSS score 0 = 14/29, score 1 = 11/29, and score 2 = 4/29) and an ascending trend in the high-grade tumor (ITSS score 0 = 4/41, score 1 = 9/41 and score 2 = 22/41). No embryonal tumor showed an ITSS score of 0. Apparent diffusion coefficient sensitivity and specificity were 82.9% and 82.8%, respectively, while rADC sensitivity and specificity were 91.4% and 86.2%, respectively. For high-grade tumors, the ITSS score 2 had a significant positive prediction (P = 0.009) and the rADC value had a significant negative prediction (P = 0.031).ConclusionsSusceptibility-weighted imaging ITSS score, ADC, and rADC have a promising role in preoperative pediatric brain tumor grading and should be considered as complementary sequences to routine MRI studies.

The Role of Apparent Diffusion Coefficient Values in Glioblastoma: Differentiating Tumor Progression Versus Treatment-Related Changes.

Glioblastoma represents the most common primary brain malignancy with a median survival of 15 months. Follow-up examinations are crucial to establish the presence of tumor recurrence, as well as treatment-associated changes such as ischemic infarction and radiation effects. Even though magnetic resonance imaging is a valuable tool, a histopathological diagnosis is often required because of imaging overlap between tumor recurrence and treatment associated changes. We set out to measure the apparent diffusion coefficient (ADC) values of the lesions in magnetic resonance imaging scans of treated glioblastoma patients to investigate if ADC values could accurately differentiate between tumor progression, radiation-related changes, and ischemic infarctions. We evaluated ADC values among 3 groups, patients with tumor progression, radiation necrosis, and ischemic infarctions. The regions of interest were placed in the areas of greatest hypointensity among solid lesions using the ADC maps, excluding areas with necrotic, cystic, or hemorrhagic changes. The ADC values of the contralateral normal appearing white matter were also measured as the reference value for each patient. The relative ADC (rADC) values were measured for all 3 groups. Comparison between lesions and normal white matter was evaluated by Wilcoxon signed test. A total of 157 patients were included in the study; 49 patients classified as tumor progression, 58 patients as radiation necrosis, and 50 patients as ischemic infarctions. The mean ± SD ADC value was 752.8 ± 132.5 for tumor progression, 479.0 ± 105.2 for radiation-related changes, and 250.1 ± 57.2 for ischemic infarctions. The mean ± SD rADC value was 1.07 ± 0.22 for tumor progression, 0.66 ± 0.14 for radiation necrosis, and 0.34 ± 0.08 for ischemic infarctions. The mean rADC values were significantly higher in tumor progression, compared with both radiation necrosis and ischemic changes ( P < 0.001). The present study demonstrates that ADC values are a helpful tool to differentiate between tumor progression, radiation necrosis, and posttreatment ischemic changes.

MRI Using Artificial Intelligence Algorithm to Evaluate Concurrent Chemoradiotherapy for Local Recurrence and Distant Metastasis of Cervical Squamous Cell Carcinoma.

The aim of this study was to investigate the magnetic resonance imaging (MRI) features of patients with local recurrence and distant metastasis of cervical squamous cell carcinoma before and after concurrent chemoradiotherapy based on artificial intelligence algorithm. In this study, 100 patients with cervical squamous cell carcinoma with local recurrence and distant metastasis who underwent concurrent chemoradiotherapy were collected as the research subjects, and all underwent MRI multisequence imaging scans. At the same time, according to the evaluation criteria of solid tumor efficacy, patients with complete remission were classified into the effective group, and patients with partial remission, progressive disease, and stable disease were classified into the ineffective group. In addition, an image segmentation algorithm based on Balloon Snake model was proposed for MRI image processing, and simulation experiments were carried out. The results showed that the Dice coefficient of the proposed model segmentation of the reconstructed image was significantly higher than that of the level set model and the greedy algorithm, while the running time was the opposite (P < 0.05). The lesion volume (38.76 ± 5.34 cm3) in the effective group after treatment was significantly smaller than that in the noneffective group (46.33 ± 4.64 cm3), and the rate of lesion volume shrinkage (28.71%) was significantly larger than that in the noneffective group (12.49%) (P < 0.05). The relative apparent diffusion coefficient (rADC) value and rADC value change rate of the lesion after treatment in the effective group were significantly greater than those in the noneffective group (P < 0.05). In summary, the image segmentation and reconstruction algorithm based on Balloon Snake model can not only improve the quality of MRI images but also shorten the processing time and improve the diagnostic efficiency. The volume regression rate and rADC value change rate of cervical squamous cell carcinoma lesion can reflect the early efficacy of concurrent chemoradiotherapy for cervical squamous cell carcinoma and have predictive value.

Differences in the MRI Signature and ADC Values of Diffuse Midline Gliomas with H3 K27M Mutation Compared to Midline Glioblastomas.

Simple SummaryDiffuse midline glioma is a rare distinct brain tumor entity introduced by the recent WHO (Lyon, France) brain tumor classification. MR imaging is important for detection as well as characterization of these midline tumors, which are located within the brainstem, since neurosurgical tissue sampling in these locations can be challenging. We therefore searched for possible differences in the MRI pattern between diffuse midline gliomas and midline glioblastomas, both regarded as grade IV entities.We conducted a two-center retrospective survey on standard MRI features including apparent diffusion coefficient mapping (ADC) of diffuse midline gliomas H3 K27M-mutant (DMG) compared to midline glioblastomas H3 K27M-wildtype (midGBM-H3wt). We identified 39 intracranial DMG and 18 midGBM-H3wt tumors. Samples were microscopically re-evaluated for microvascular proliferations and necrosis. Image analysis focused on location, peritumoral edema, degree of contrast enhancement and DWI features. Within DMG, MRI features between tumors with or without histomorphological GBM features were compared. DMG occurred in 15/39 samples from the thalamus (38%), in 23/39 samples from the brainstem (59%) and in 1/39 tumors involving primarily the cerebellum (2%). Edema was present in 3/39 DMG cases (8%) versus 78% in the control (midGBM-H3wt) group (p < 0.001). Contrast enhancement at the tumor rim was detected in 17/39 DMG (44%) versus 67% in control (p = 0.155), and necrosis in 24/39 (62%) versus 89% in control (p = 0.060). Strong contrast enhancement was observed in 15/39 DMG (38%) versus 56% in control (p = 0.262). Apparent diffusion coefficient (ADC) histogram analysis showed significantly higher skewness and kurtosis values in the DMG group compared to the controls (p = 0.0016/p = 0.002). Minimum relative ADC (rADC) values, as well as the 10th and 25th rADC-percentiles, were lower in DMGs with GBM features within the DMG group (p < 0.001/p = 0.012/p = 0.027). In conclusion, DMG cases exhibited markedly less edema than midGBM-H3wt, even if histomorphological malignancy was present. Histologically malignant DMGs and midGBM-H3wt more often displayed strong enhancement, as well as rim enhancement, than DMGs without histomorphological malignancy. DMGs showed higher skewness and kurtosis values on ADC-histogram analysis compared to midGBM-H3wt. Lower minimum rADC values in DMGs indicated malignant histomorphological features, likely representing a more complex tissue microstructure.

Intravoxel Incoherent Motion Magnetic Resonance Imaging Used in Preoperative Screening of High-Risk Patients With Moyamoya Disease Who May Develop Postoperative Cerebral Hyperperfusion Syndrome.

ObjectiveThis study aimed to investigate the feasibility of preoperative intravoxel incoherent motion (IVIM) MRI for the screening of high-risk patients with moyamoya disease (MMD) who may develop postoperative cerebral hyperperfusion syndrome (CHS).MethodsThis study composed of two parts. In the first part 24 MMD patients and 24 control volunteers were enrolled. IVIM-MRI was performed. The relative pseudo-diffusion coefficient, perfusion fraction, apparent diffusion coefficient, and diffusion coefficient (rD*, rf, rADC, and rD) values of the IVIM sequence were compared according to hemispheres between MMD patient and healthy control groups. In the second part, 98 adult patients (124 operated hemispheres) with MMD who underwent surgery were included. Preoperative IVIM-MRI was performed. The rD*, rf, rADC, rD, and rfD* values of the IVIM sequence were calculated and analyzed. Operated hemispheres were divided into CHS and non-CHS groups. Patients’ age, sex, Matsushima type, Suzuki stage, and IVIM-MRI examination results were compared between CHS and non-CHS groups.ResultsOnly the rf value was significantly higher in the healthy control group than in the MMD group (P < 0.05). Out of 124 operated hemispheres, 27 were assigned to the CHS group. Patients with clinical presentation of Matsushima types I–V were more likely to develop CHS after surgery (P < 0.05). The rf values of the ipsilateral hemisphere were significantly higher in the CHS group than in the non-CHS group (P < 0.05). The rfD* values of the ACA and MCA supply areas of the ipsilateral hemisphere were significantly higher in the CHS group than in the non-CHS group (P < 0.05). Only the rf value of the anterior cerebral artery supply area in the contralateral hemisphere was higher in the CHS group than in the non-CHS group (P < 0.05). The rf values of the middle and posterior cerebral artery supply areas and the rD, rD*, and rADC values of the both hemispheres were not significantly different between the CHS and non-CHS groups (P > 0.05).ConclusionPreoperative non-invasive IVIM-MRI analysis, particularly the f-value of the ipsilateral hemisphere, may be helpful in predicting CHS in adult patients with MMD after surgery. MMD patients with ischemic onset symptoms are more likely to develop CHS after surgery.

Apparent diffusion coefficient signature of ischemic tissue predicts neurological progression in isolated pontine infarcts.

Early neurological deterioration is encountered in up to a third of patients with isolated pontine infarcts. A limited number of clinical and imaging features have been suggested as predictors of neurological progression in this setting. In this study, we assessed whether quantitative apparent diffusion coefficient (ADC) measurements within the ischemic pontine region could be used as a radiomic feature to forecast clinical deterioration. We calculated the mean ADC value of ischemic voxels within the ischemic region and normalized them to the contralateral non-ischemic tissue (relative ADC, rADC) in patients with isolated pontine infarcts. This imaging signature was then compared among patients with neurological progression (n = 21) and a propensity matched cohort of non-progressors (n = 42), together with other clinical and imaging features in bivariate and multivariate statistical models. The rADCmean was significantly lower among patients with progression (p = 0.008). Female gender and extension of the ischemic lesion to the ventral pontine surface were other features significantly associated with progression. The association between rADCmean and progression persisted in multivariate models with an odds ratio of 13.7 (95% CI 2.6-72.8; p = 0.002) for progression among patients with rADCmean ≤ 0.67 in their ischemic tissue. The probability for worsening was 80% among patients who had an ischemic lesion extending to the ventral pontine surface with a mean rADC ≤ 0.67. The mean rADC value within the ischemic lesion is closely related with early neurological deterioration in patients with isolated pontine infarcts.

Combining hyperintense FLAIR rim and radiological features in identifying IDH mutant 1p/19q non-codeleted lower-grade glioma.

Even very small residual tumors of IDH mutant 1p/19q non-codeleted (IDHmut-Noncodel) astrocytoma could have a significantly negative impact on survival; thus, accurate preoperative diagnosis is of utmost importance to guide aggressive tumor resection strategy for this subtype. This study aimed to diagnose IDHmut-Noncodel from IDH mutant 1p/19q codeleted (IDHmut-Codel) and IDH wild-type gliomas by preoperative MRI and CT to guide surgical plan-making. Consecutive adult patients diagnosed with diffuse lower-grade glioma (LGG, histological grade 2-3) from December 1, 2013 to December 31, 2020, were retrospectively included in this study. Clinical and radiological features were recorded and analyzed. Patients were divided into cohort A and cohort B for training and validation based on the operation date (2:1). A total of 585 patients were included in this study (cohort A, 390; cohort B, 195). The hyperintense FLAIR rim with hypointense core (hyperFLAIRrim) was a more sensitive sign than T2-FLAIR mismatch (T2FM) in defining IDHmut-Noncodel astrocytoma (sensitivity in cohort A: 0.713, 0.539, respectively; in cohort B: 0.713, 0.489, respectively) without compromised specificity (all 1.00). The hyperFLAIRrim, higher rADC, homogenous pattern on T2WI, non-calcification, and younger age were the most important factors associated with IDHmut-Noncodel astrocytoma. Combining these factors, the random forest model showed the best predictive ability. The hyperFLAIRrim sign was a specific and more sensitive sign in diagnosing IDHmut-Noncodel astrocytoma. Combining hyperFLAIRrim, higher rADC, homogenous pattern, non-calcification, and younger age could precisely predict glioma subtype for subsequent surgical plan-making. • A single hyperintense FLAIR rim (hyperFLAIRrim) sign with a hypointense core, regardless of T2 appearance, was more sensitive than T2FM in diagnosing IDHmut-Noncodel astrocytoma with high specificity. • The higher rADC value, homogenous pattern on T2WI, non-calcification, and younger age have a close relationship with IDHmut-Noncodel astrocytoma. • Neurosurgeons should perform a more aggressive resection strategy to prolong survival for radiologically indicated IDHmut-Noncodel astrocytoma. Our study provided a usable, practicable, and reliable protocol for neurosurgeons to make an individualized surgical strategy.

The role of apparent diffusion coefficient (ADC) in the evaluation of lymph node status in patients with locally advanced cervical cancer: our experience and a review.

PurposeTo evaluate the role of apparent diffusion coefficient (ADC) value measurement in the diagnosis of meta-static lymph nodes (LNs) in patients with locally advanced cervical cancer (LACC) and to present a systematic review of the literature.Material and methodsMagnetic resonance imaging (MRI) exams of patients with LACC were retrospectively eva-luated. Mean ADC, relative ADC (rADC), and correct ADC (cADC) values of enlarged LNs were measured and compared between positron emission tomography (PET)-positive and PET-negative LNs. Comparisons were made using the Mann-Whitney U-test and Student’s t-test. ROC curves were generated for each parameter to identify the optimal cut-off value for differentiation of the LNs. A systematic search in the literature was performed, exploring several databases, including PubMed, Scopus, the Cochrane library, and Embase.ResultsA total of 105 LNs in 34 patients were analysed. The median ADC value of PET-positive LNs (0.907 × 10-3 mm2/s [0.780-1.080]) was lower than that in PET-negative LNs (1.275 × 10-3 mm2/s [1.063-1.525]) (p < 0.05). rADC and cADC values were lower in PET-positive LNs (rADC: 0.120 × 10-3 mm2/s [–0.060-0.270]; cADC: 1.130 [0.980-1.420]) than in PET-negative LNs (rADC: 0.435 × 10-3 mm2/s [0.225-0.673]; cADC: 1.615 [1.210-1.993]) LNs (p < 0.05). ADC showed the highest area under the curve (AUC 0.808).ConclusionsMean ADC, rADC, and cADC were significantly lower in the PET-positive group than in the PET-negative group. The ADC cut-off value of 1.149 × 10-3 mm2/s showed the highest sensitivity. These results confirm the usefulness of ADC in differentiating metastatic from non-metastatic LNs in LACC.

Differentiating atypical meningioma from anaplastic meningioma using diffusion weighted imaging

PurposeTo explore the value of MRI conventional features and apparent diffusion coefficient (ADC) on the differential diagnosis of atypical meningioma (AtM) and anaplastic meningioma (AnM). Materials and methodsThis retrospective study analyzed the preoperative clinical data, MRI conventional features, and DWI data of 55 AtM and 25 AnM confirmed by pathology in our hospital. The clinical features, MRI conventional features, ADCmean, ADCmin, and relative ADC (rADC) values were compared between the two tumors by Chi-square test or an independent sample t-test. Receiver operating characteristic curve (ROC) and binary logistic regression analysis were used to evaluate the diagnostic efficacy of each parameter to differentiate between these tumors. ResultsThe MRI conventional features had a certain ability to distinguish AnM and AtM, with an area under the curve value (AUC) of 0.824 (95% CI, 0.723–0.900). The ADCmean, ADCmin, and rADC values were significantly higher in AtM compared to AnM (all P < 0.05). ADCmean had the best identification effect with an AUC of 0.867 (95% CI, 0.772–0.933) among them, at an cut-off of 0.817 × 10−3 mm2/s, the sensitivity and specificity of distinguishing AtM from AnM were 78.18% and 88.00%, respectively. A combination of ADCmean and MRI conventional features showed the optimum discrimination ability for the two tumors, the AUC, sensitivity, specificity, and accuracy were 0.918 (95% CI, 0.835–0.967), 80.00%, 94.55%, and 90.00%, respectively. ConclusionMRI conventional features combined with ADCmean, as a non-invasive method, has potential clinical value in the preoperative diagnosis of AtM and AnM.

Distinguishing Tumor Recurrence From Radiation Necrosis in Treated Glioblastoma Using Multiparametric MRI

The purpose of this study was to evaluate the diagnostic performance of single-parameter, unimodal and bimodal magnetic resonance imaging (MRI) in differentiating tumor recurrence (TR) from radiation necrosis (RN) in patients with glioblastoma (GBM) after treatment using diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), dynamic susceptibility contrast enhancement-perfusion weighted imaging (DSC-PWI), and proton magnetic resonance spectroscopy (1H-MRS). Patients with histologically proven GBM who underwent surgical intervention followed by chemoradiotherapy and developed a new, progressively enhanced lesion on follow-up MRI were included in our study. Subsequently, DWI, DTI, DSC-PWI, and 1H-MRS were performed. Then, these patients underwent a second surgical operation or follow-up MRI to prove TR or RN. MRI metrics include apparent diffusion coefficient (ADC) and relative ADC (rADC) values derived from DWI; fractional anisotropy (FA), axial diffusion coefficient (DA) and radial diffusion coefficient (DR) values derived from DTI; and relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) derived from DSC-PWI. Spectral metabolites such as choline (Cho), creatine (Cr), N-acetylaspartate (NAA), lactate (Lac), and lipids (Lip) were derived from MRS, and the ratios of these metabolites were calculated, including Cho/NAA, Cho/Cr, NAA/Cr, Lac/Cr, and Lip/Cr. These indices were compared between the TR group and RN group, and the receiver operating characteristic (ROC) curve was used to evaluate the performance in distinguishing TR from RN by using single-parameter, unimodal and bimodal MRI. There were significant differences between the TR and RN groups in terms of ADC (p=0.001), rADC (p < 0.001), FA (p=0.001), DA (p=0.003), DR (p=0.003), rCBV (p < 0.001), rCBF (p < 0.001), Cho/NAA (p < 0.001), Lac/Cr (p < 0.001) and Lip/Cr (p < 0.001). ROC analysis suggested that rCBV, MRS, and DSC+MRS were the optimal single-parameter, unimodal, and bimodal MRI classifiers for distinguishing TR from RN, with AUC values of 0.909, 0.940, and 0.994, respectively. The combination of parameters based on multiparametric MRI in the region of enhanced lesions is a valuable noninvasive tool for discriminating TR from RN.

Exercise Intervention Promotes the Growth of Synapses and Regulates Neuroplasticity in Rats With Ischemic Stroke Through Exosomes.

Background: Stroke is the leading cause of death and disability. Exercise produces neuroprotection by improving neuroplasticity. Exercise can induce exosome production. According to several studies, exosomes are involved in repairing brain function, but the relationship and mechanism of exercise, exosomes, and neuroprotection have not been elucidated. This study intends to explore the relationship and potential mechanism by observing the changes in the exosome level, infarct volume, neurological function and behavioral scores, synapses, and corticospinal tract (CST).Methods: Rats were randomly divided into four groups: a sham operation (SHAM) group, middle cerebral artery occlusion (MCAO) with sedentary intervention (SED-MCAO) group, MCAO with exercise intervention (EX-MCAO) group, and MCAO with exercise intervention and exosome injection (EX-MCAO-EXO) group. The exercise intervention was started 1 day after MCAO and lasted for 4 weeks. All rats were assessed using the modified neurological severity score (mNSS). The levels of exosomes in serum and brain, gait analysis, and magnetic resonance scan were performed 1 and 4 weeks after the intervention. After 4 weeks of intervention, the number of synapses, synaptophysin (Syn), and postsynaptic density protein 95(PSD-95) expression was detected.Results: After 4 weeks of intervention, (1) the EX-MCAO and EX-MCAO-EXO groups showed higher serum exosome (pEX−MCAO = 0.000, pEX−MCAO−EXO = 0.000) and brain exosome (pEX−MCAO = 0.001, pEX−MCAO−EXO = 0.000) levels than the SED-MCAO group, of which the EX-MCAO group had the highest serum exosome (p = 0.000) and the EX-MCAO-EXO group had the highest brain exosome (p = 0.03) levels. (2) The number of synapses in the EX-MCAO (p = 0.032) and EX-MCAO-EXO groups (p = 0.000) was significantly higher than that in the SED-MCAO group. The EX-MCAO-EXO group exhibited a greater number of synapses than the EX-MCAO (p = 0.000) group. (3) The synaptic plasticity-associated proteins were expressed significantly higher in the EX-MCAO (pSyn = 0.010, pPSD−95 = 0.044) and EX-MCAO-EXO (pSyn = 0.000, pPSD−95 = 0.000) groups than in the SED-MCAO group, and the EX-MCAO-EXO group (pSyn = 0.000, pPSD−95 = 0.046) had the highest expression. (4) Compared with the SED-MCAO group, the EX-MCAO group had significantly improved infarct volume ratio (p = 0.000), rFA value (p = 0.000), and rADC (p = 0.000). Compared with the EX-MCAO group, the EX-MCAO-EXO group had a significantly improved infarct volume ratio (p = 0.000), rFA value (p = 0.000), and rADC value (p = 0.001). (5) Compared with the SED-MCAO group, the EX-MCAO group (p = 0.001) and EX-MCAO-EXO group (p = 0.000) had significantly lower mNSS scores and improved gait. (6) The brain exosome levels were negatively correlated with the mNSS score, infarct volume ratio, and rADC value and positively correlated with the rFA value, Syn, and PSD-95 expression. The serum and brain exosome levels showed a positive correlation.Conclusions: Exercise intervention increases the serum exosome level in MCAO rats, which are recruited into the brain, leading to improved synaptic growth and CST integrity, a reduced infarct volume, and improved neurological function and gait.

Dynamic Observation of the Effect of L-Theanine on Cerebral Ischemia-Reperfusion Injury Using Magnetic Resonance Imaging under Mathematical Model Analysis.

This study was to use the partial differential mathematical model to analyze the magnetic resonance imaging (MRI) images of cerebral ischemia-reperfusion injury (CIRI) and to dynamically observe the role of L-theanine in CIRI based on this. 30 patients with cerebral ischemia in a hospital in a certain area were selected and divided into a cerebral ischemia group and a L-theanine treatment group. The two groups of patients were examined by MRI within 48 hours, and the relative apparent diffusion coefficient (rADC) of the cerebral ischemic part of the patients was determined. The partial differential mathematical model was used for data processing to obtain the function of cerebral ischemia time and infarct area, and the data of patients in the cerebral ischemia group and L-theanine treatment group were compared and analyzed. The results showed that the partial differential mathematical model could effectively analyze the linear relationship between the rADC value and time in the treatment of CIRI using L-theanine. The rADC values of the four points of interest in the L-theanine treatment group all increased with time, and there was a positive correlation between the variables X and Y. In observing the efficacy indicators of L-theanine, the L-theanine treatment group showed a significant advantage in the neurospecific enolase (NSE) content compared with the cerebral ischemia group (P < 0.01), and the neurological function score of the L-theanine treatment group gradually decreased and showed a statistically obvious difference on the 7th day of treatment (P < 0.05). In summary, it was verified in this study that the role of L-theanine in the treatment of CIRI was of a great and positive significance for the subsequent treatment of patients with cerebral ischemia, providing reliable theoretical basis and data basis for clinical treatment of CIRI.

The diagnostic dilemma with the plateau pattern of the time–intensity curve: can the relative apparent diffusion coefficient (rADC) optimise the ADC parameter for differentiating breast lesions?

To assess the performance of the apparent diffusion coefficient (ADC) and relative ADC (rADC) to differentiate benign from malignant breast lesions using the plateau pattern of the time-intensity curve (Type II TIC), including the impact of lesions-enhancement subtypes and menopausal status of patients. Between September 2016 and December 2019, 408 patients with 169 benign and 239 malignant lesions with Type II TIC underwent magnetic resonance imaging (MRI), including diffusion-weighted imaging, with b-values of 50 and 800 s/mm2. ADC and rADC values were calculated by placing regions of interest (ROIs) on the lesion, the parenchyma of the normal breast, and the pectoralis major muscle. A receiver operating characteristic (ROC) curve was generated to compare the diagnostic performance of each parameter in distinguishing between benign and malignant breast lesions. Further classification was undertaken to study the discriminatory performance of each parameter in the different lesions enhancement subtypes (mass-like enhancement [MLE] and non-MLE [NMLE]) and menopausal status of patients (pre-menopausal and post-menopausal). There was a significant difference in the ADC and rADC values between benign and malignant lesions. The sensitivities of lesion ADC, gland rADC, and muscle rADC were 79.29%, 77.51%, and 79.29%, respectively, with specificities of 94.56%, 82.01%, and 94.98%, respectively. The area under the ROC curve (AUC) of muscle rADC was the highest (AUC=0.92), especially in the MLE subtype (AUC=0.96), and was not affected by the menopausal status. Muscle rADC and lesion ADC assessment improved the diagnostic performance of breast MRI in distinguishing between benign and malignant breast lesions with Type II TIC, especially muscle rADC in the MLE subtype.