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Resumen Objetivo: El objetivo del tratamiento en accidente cerebrovascular (ACV) isquémico agudo es restablecer la circulación en el área de la penumbra isquémica. La secuencia de susceptibilidad (SWI) puede detectar cambios en el calibre de las venas intracraneanas cuando se altera la relación desoxiHb/oxiHb en áreas hipoperfundidas, lo que permitiría una detección temprana de penumbra isquémica. Material y métodos: Estudio de cohorte retrospectivo. Se incluyeron pacientes con infartos agudos en territorio de la arteria cerebral media. Se evaluaron las secuencias difusión y SWI iniciales y un estudio de control a los siete días. La extensión del ACV se midió con la escala ASPECT en difusión y SWI del ingreso, y en el estudio de control. Se estableció una discordancia SWI/difusión > 2 puntos como variable predictora y la extensión final del infarto como variable de resultado. Resultados: Se incluyeron 31 pacientes, mediana de edad de 72 años (RIC: 61-81). En 13 pacientes se detectó una oclusión vascular proximal, ocho de los cuales tenían discordancia SWI/difusión > 2 puntos (p < 0,0001). En cinco pacientes encontramos incremento del infarto, cuatro con discordancia SWI/difusión (p = 0,01). Conclusión: La presencia de discordancia SWI/difusión puede ser un biomarcador de penumbra isquémica en pacientes con oclusión vascular proximal.
Abstract Objective: The goal of treatment in acute ischemic stroke is to restore circulation in the area of the ischemic penumbra. Susceptibility weighted imaging (SWI) can detect changes in the caliber of intracranial veins when the deoxyHb/oxyHb ratio is altered in hypoperfused areas, which would allow early detection of ischemic penumbra. Material and methods: Retrospective cohort study. Patients with acute infarcts in the territory of the middle cerebral artery were included. Initial diffusion and SWI sequences and a control study at seven days were evaluated. Stroke extension was measured with the ASPECT scale in diffusion and SWI on admission, and in the control study. An SWI/diffusion discrepancy > 2 points was established as a predictor variable and the final extension of the infarct as a result variable. Results: Thirty-one patients were included, median age 72 years (IQR: 61-81). Proximal vascular occlusion was detected in 13 patients, 8 of whom had SWI/diffusion discordance > 2 points (p < 0.0001). In 5 patients we found increased infarction, 4 with SWI/diffusion mismatch (p = 0.01). Conclusion: The presence of SWI/diffusion mismatch may be a biomarker of ischemic penumbra in patients with proximal vascular occlusion.
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Background: Stroke is a prevalent and potentially fatal medical condition that affects individuals worldwide. Ischemic strokes, caused by arterial blockages, are the most common type, accounting for about 80% of all cases. Hemorrhagic strokes, on the other hand, are less frequent but can have more severe consequences. Accurate and timely diagnosis of stroke is critical for effective treatment and optimal patient outcomes. In this context, diffusion-weighted imaging (DWI) has emerged as a valuable tool for identifying and monitoring ischemic stroke. This article provides an overview of the role of DWI in stroke assessment and management, with a focus on early detection and intervention. The aim of this study is to investigate the reliability of diffusion-weighted MRI (DWI) as an imaging modality in the evaluation of acute ischemic stroke. Material & Methods: This prospective cross-sectional study was conducted at the Department of Radiology and Imaging at the Combined Military Hospital (CMH) in Dhaka, Bangladesh, between June 2020 and June 2021. The study aimed to examine 120 patients clinically diagnosed with acute ischemic stroke. Prior to the study, verbal consent was obtained from all patients. The Study subjects were identified in the emergency and casualty department and had undergone an MRI of the brain in the Department of Radiology and Imaging at CMH, Dhaka. . Data were collected on pre-designed forms, and the relevant information was compiled on a master chart for statistical analysis using SPSS software. Descriptive analysis and frequency of results were presented in the form of tables, pie charts, and bar graphs. The ethical clearance of this study was obtained from the Institutional Ethics Committee of CMH, Dhaka, Bangladesh. Results: The study included 64 males and 56 females with a mean age of 65.2 ± 7.83 years. The majority of patients had an acute ischemic lesion (88.30%) in the MCA (50.0%) with small-sized lesions (41.7%) and low ADC values (90.0%). The most common clinical presentation was hemiplegia (100%), and diffusion-weighted MRI had a high diagnostic accuracy in detecting acute ischaemic lesions (96.3%). Overall, these findings highlight the importance of MRI in the evaluation of stroke patients and can guide clinical decision-making. Conclusion: The present study concluded that DWI in conjunction with ADC map MR imaging is a gold standard diagnostic modality in the evaluation and management of acute ischaemic stroke.
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Objective To investigate the correlation between ADC value and glioma IDH-1/1p19q genotype. Methods The MRI features and molecular pathological results of 69 patients with pathologically confirmed diagnosis of WHO grade Ⅱ/Ⅲ glioma between March 2013 and December 2020 were retrospectively analyzed. The diagnostic performance of ADC values on glioma genotypes (IDH-1, 1p19q) was evaluated using the ROC curve of the subjects' working characteristics. Results The ADCmean, ADCmin, rADCmean, and rADCmin in the IDH-1 mutation group were significantly higher than those in the IDH-1 wild group (P < 0.05, P < 0.01, P < 0.05, P < 0.01). The use of the rADCmin threshold (0.979×103mm2/s) had the highest efficacy (AUC=0.770) for diagnosis of IDH-1 mutant and IDH-1 wild-type gliomas as well as sensitivity and specificity of 84.61% and 59.09%, respectively. Conclusion ADC can be used as an imaging biomarker for noninvasive prediction of IDH-1 mutant and wild-type Ⅱ /Ⅲ gliomas.
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ObjectiveTo investigate the value of reduced field-of-view DWI （r-FOV DWI） in quantitative assessment of axial spondyloarthritis. MethodsA total of 112 patients with chronic back pain or suspected axial spondyloarthritis receiving full field-of-view DWI （f-FOV DWI） and reduced field-of-view DWI （r-FOV DWI） from December 2019 to December 2021 were enrolled. Next， subjective image quality assessment （anatomical detail， artifacts， distortion， overall image quality） and objective image quality assessment including （signal to noise ratio and contrast to noise ratio） were conducted by two experienced radiologists. In addition， the Apparent Diffusion Coefficient （ADC） values of three groups （active group， inactive group， and control group） on the two DWI sequences were measured by the two radiologists， respectively. Finally， the consistency of measurement between the two researchers was evaluated and the differences in ADC values was compared. Results102 patients were included and were divided into three groups， including the active group （n=32）， inactive group （n=29）， and control group （n=41） according to ASAS diagnostic criteria. All subjective and objective image quality metrics were rated in favor of r-FOV DWI images compared with f-FOV DWI images ［overall image quality： DWI 4（3~4） vs. 3（3~3） and SNR： 6.58（5.05~10.38） vs. 4.46（2.37~10.04）， CNR： 2.04（-1.14~8.29） vs. 0.97（-8.19~7.12）；P＜0.05］. Inter-rater consistency of the two researchers were 0.60~0.74. According to the AUC curve， group inactive vs. control showed r-FOV DWI was better than f-FOV DWI. In other groups （lesion vs. control， active vs. inactive）， there were no differences between both sequences（P＜0.05）. ConclusionThe subjective image quality score and signal to noise ratio of r-FOV DWI were higher than those of f-FOV DWI， which could be used for quantitative assessment of axial spondyloarthritis.
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OBJECTIVES@#Magnetic resonance diffusion-weighted imaging (DWI) has important clinical value in diagnosis and curative effect evaluation on endometrial carcinoma. How to improve the detection rate of endometrial small lesions by DWI is the research focus of MRI technology. This study aims to analyze the image quality of small field MRI ZOOMit-DWI sequence and conventional single-shot echo-planar imaging (SS-EPI) DWI sequence in the scanning of endometrial carcinoma, and to explore the clinical value of ZOOMit-DWI sequence.@*METHODS@#A total of 37 patients with endometrial carcinoma diagnosed by operation and pathology in the Second Xiangya Hospital of Central South University from July 2019 to May 2021 were collected. All patients were scanned with MRI ZOOMit-DWI sequence and SS-EPI DWI sequence before operation. Two radiologists subjectively evaluated the anatomical details, artifacts, geometric deformation and focus definition of the 2 groups of DWI images. At the same time, the signal intensity were measured and the signal-to-noise ratio (SNR), contrast to noise ratio (CNR), and apparent diffusion coefficient (ADC) of the 2 DWI sequences were calculated for objective evaluation. The differences of subjective score, objective score and ADC value of the 2 DWI sequences were analyzed.@*RESULTS@#The SNR of the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (301.96±141.85 vs 94.66±41.26), and the CNR of the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (185.05±105.45 vs 57.91±31.54, P<0.05). There was no significant difference in noise standard deviation between the ZOOMit-DWI group and the SS-EPI DWI group (P>0.05). The subjective score of anatomical detail and focus definition in the ZOOMit-DWI group was significantly higher than that of the SS-EPI DWI group (both P<0.05). The subjective score of artifacts and geometric deformation of ZOOMit-DWI group was significantly lower than that of the SS-EPI DWI group (both P<0.05). ADC had no significant difference between the ZOOMit-DWI group and the SS-EPI DWI group (P>0.05).@*CONCLUSIONS@#The image quality of ZOOMit-DWI is significantly higher than that of conventional SS-EPI DWI. In the MRI DWI examination of endometrial carcinoma, ZOOMit-DWI can effectively reduce the geometric deformation and artifacts of the image, which is more conducive to clinical diagnosis and treatment.
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Female , Humans , Signal-To-Noise Ratio , Endometrial Neoplasms/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Endometrium , Echo-Planar Imaging/methods , Reproducibility of ResultsABSTRACT
Background: Hepatocellular carcinoma (HCC) is considered one of the foremost cancers worldwide. Although the hepatic resection of HCC has a high existence in the clinical scenarios, locoregional management is preferred owing to the preservation of hepatic parenchyma with lower morbidity and mortality. Dynamic contrast-enhanced MR with subtraction imaging improves the evaluation of managed HCC with easy detection of residual or recurrent viable lesions. Patients and methods: This study was designed in a retrospective pattern from December 2020 to December 2022. Forty patients were referred to our radiology department with solitary HCC, underwent therapeutic intervention, then underwent follow-up by dynamic MRI study. Results: Forty patients with solitary HCC were conducted during our study; all underwent locoregional therapy with follow-up by dynamic MRI with subtraction technique one month later. The subtraction image has a sensitivity of 100%, specificity of 100%, PPV of 100%, NPV of 100%, and 100% accuracy, compared to 90.91%, 77.78%, 83.33%, 87.5%, and 85% for conventional dynamic images, 45.45%, 100%, 100%, 60% and 70% for diffusion-weighted images. Analysis of those results exhibited a considerable additive value of the subtraction technique to the dynamic MRI to detect the response of HCC after management. Conclusions: Subtraction MRI is a pivotal tool to assess the interventional treatment of HCC, particularly in lesions having pre-contrast high signal intensity with distinguished radiologists' confidence
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Humans , Male , Female , Magnetic Resonance Imaging , Sensitivity and Specificity , Liver Neoplasms , Treatment Outcome , DiagnosisABSTRACT
Background: At present, the diagnosis and efficacy evaluation of acute leukemia (AL) are assessed by bone marrow aspiration, which is invasive and subject to sampling errors. Therefore, there is a pressing need to develop a noninvasive and accurate imaging method to evaluate bone marrow changes in patients with AL. This study aimed to compare the apparent diffusion coefficient (ADC) values obtained from fluid?attenuated inversion recovery diffusion?weighted imaging (FLAIR?DWI) and conventional DWI in the lumbar bone marrow of patients with AL and to investigate their performance for evaluating response to induction chemotherapy. Methods: A total of 28 patients with newly diagnosed AL and 25 patients with AL after induction chemotherapy underwent MRI scans at 1.5 Tesla using a conventional DWI and a FLAIR?DWI sequence on sagittal planes covering the lumbar bone marrow. Further, the ADC values from these two sequences, denoted as ADCCON and ADCFLAIR, were measured on multiple vertebrae. The percentage of leukemia cells in bone marrow was recorded, and bone marrow aspiration was performed on treated patients to determine complete remission (CR) and nonremission (NR). Results: ADCFLAIR [(0.453 ± 0.103) × 10?3 mm2/s] was significantly lower than ADCCON [(0.486 ± 0.096) × 10?3 mm2/s] in the 28 untreated patients (t = 3.051, P = 0.005). In the 25 treated patients, ADCFLAIR and ADCCON values [(0.566 ± 0.239) × 10?3 mm2/s] and [(0.716 ± 0.235) × 10?3 mm2/s], respectively, were higher compared with the untreated patients. The ADCCON values showed a nonsignificant difference between the CR (n = 18) and NR (n = 7) groups (t = 1.409, P = 0.305). However, the ADCFLAIR values exhibited statistically significant difference (t = 2.542, P = 0.018) between the two groups. In a receiver operator characteristic (ROC) analysis, the area under the curve (AUC) using ADCFLAIR (0.770) was larger than that of ADCCON (0.611) in distinguishing the CR and NR patients following the chemotherapy. Conclusion: Although both ADCCON and ADCFLAIR are sensitive to tissue changes induced by chemotherapy, FLAIR?DWI outperformed conventional DWI in separating AL patients with CR from NR after chemotherapy. A possible mechanism is that FLAIR?DWI suppresses signals from free water, making the ADC measurement more sensitive to structural changes in the bone marrow
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Resumen Introducción: La imagen ponderada en difusión es una técnica de imagen funcional que aporta información complementaria a las secuencias convencionales de resonancia magnética. El coeficiente de difusión aparente (CDA) se valora junto con la secuencia de difusión, calculando el logaritmo negativo de la proporción de intensidades de dos conjuntos de imágenes, lo que permite el análisis cuantitativo de la restricción a la difusión. Objetivo: Determinar si existe una diferencia significativa entre los valores de CDA de las lesiones musculoesqueléticas benignas y malignas, correlacionando los resultados con los hallazgos histológicos. Método: Estudio prospectivo, observacional y descriptivo. Se incluyeron en el trabajo pacientes con sospecha de lesiones tumorales del sistema musculoesquelético de cualquier edad y sexo, sin antecedentes de radioterapia previa o cirugía, evaluados con resonancia magnética y con posterior biopsia o cirugía. Resultados: Se incluyeron 170 pacientes, de los cuales 80 (44 benignos) eran hombres y 90 (43 benignos) eran mujeres. El total fue de 87 lesiones benignas y 83 lesiones malignas, con una media de CDA de 1,44 ± 0,55 × 10−3 mm2/s y de 0,96 ± 0,4 × 10−3 mm2/s, respectivamente, con una diferencia estadísticamente significativa (p < 0,001; 6,335; 168). Conclusiones: Los valores de difusión, y particularmente el CDA, han aportado información adicional en la caracterización de los tumores benignos y malignos, con diferencia significativa, estableciendo valores altos de CDA para los tumores benignos.
Abstract Introduction: Diffusion-weighted imaging is a functional imaging technique that provides complementary information to conventional magnetic resonance imaging sequences. The apparent diffusion coefficient (ADC) is evaluated together with the diffusion sequence, calculating the negative logarithm of the intensity ratio of two image sets, allowing the quantitative analysis of the diffusion. Objective: To determine if there is a statistical significance between the ADC values of benign and malignant musculoskeletal lesions, correlating the results with the histological findings. Method: Prospective, observational and descriptive study. Patients with suspected tumoral lesions of the musculoskeletal system of any age and sex, with no history of prior radiation therapy or surgery, evaluated with resonance with subsequent biopsy or surgery. Results: This study included 170 patients. Male patients were 80 (44 benign), and female patients were 90 (43 benign). The total was 87 benign lesions and 83 malignant lesions, with a mean ADC of 1.44 ± 0.55 × 10−3 mm2/s and 0.96 ± 0.4 × 10−3 mm2/s respectively, with a statistical significance (p < 0.001; 6.335; 168). Conclusions: Diffusion and, in particular, ADC values have provided additional information in the characterization of benign and malignant tumors, with a statistical significance, establishing high ADC values for benign tumors.
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@#Introduction: Intravenous thrombolysis (IVT) is the gold standard for the treatment of patients with acute ischemic stroke (AIS) presenting within four and a half hours of onset. However, development of new thrombolytic agents and advanced imaging has led to extended time for thrombolysis based on advanced imaging. Here we describe four patients who presented in the extended hours; that benefitted from thrombolysis. Case series: We advocate magnetic resonance imaging (MRI) for AIS, that includes diffusion weighted imaging (DWI), apparent diffusion coefficient (ADC), fluid attenuated inversion recovery (FLAIR), susceptibility weighted imaging (SWI), and magnetic resonance angiography (MRA). We included four patients who were more than 18 years old, with National Institute of Health Stroke Scale (NIHSS) of six or more, presenting between four and a half to nine hours after stroke onset with no contraindications for intravenous thrombolysis. The imaging criteria used to determine eligibility for IVT is evidence of DWI-FLAIR mismatch on MRI. If FLAIR detects no signal change in the area of stroke on DWI, it is then termed DWIFLAIR mismatch, or FLAIR-negative – indicating high probability that the brain tissue is still viable, and that patients are good candidates for IVT. Conclusion: For patients with AIS who present within nine hours, DWI-FLAIR mismatch serves as an excellent surrogate marker of salvageable brain tissue, allowing a greater proportion of patients benefiting from this life-saving therapy. Our experience also shows that with careful patient selection, treatment with IVT can safely be given without an increased risk of bleeding or mortality.
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Objective:To explore the value of BLADE sequence in determining the target range of esophageal cancer radiotherapy through the correlation and consistency between measured esophageal cancer length on the MRI-BLADE sequence and the surgical pathological specimens.Methods:Clinical data of 36 patients who were pathologically diagnosed with esophageal carcinoma and received preoperative esophageal MRI in the Affiliated Cancer Hospital of Zhengzhou University between January 2016 to June 2019 were collected. The CT, DWI and BLADE sequence images of all participants were collected and imported into the Monaco system, by which the correlation and consistency between the tumor length measured based on these three imaging methods were statistically compared. Furthermore, the differences in gross tumor volume (GTV) delineated by different physicians in different images were compared.Results:The correlation coefficients of the tumor length measured by CT, DWI and BLADE and pathological specimen length were 0.467, 0.723 and 0.896, respectively. The consistency analysis indicated that all the differences between the BLADE sequence and pathological specimen length were within the 95% consistency limit. The consistency and correlation between the BLADE sequence and actual tumor length were significantly better than those between the DWI sequence and CT images (both P<0.05). The volume of DWI and BLADE images obtained by four physicians was significantly smaller than that of CT images (both P<0.05). The differences in GTV delineated by different physicians by these three imaging methods were insignificant (all P>0.05), but the GTV delineated by the four physicians on the BLADE sequence were more similar (all P>0.05). Conclusions:BLADE sequence can help physicians to determine the upper and lower boundaries of esophageal tumors more accurately and reduce the differences in GTV delineation among different physicians. And it can effectively improve the unity of individual′s understanding of the scope of target area delineation, and improve the objectivity of clinicians′ judgment of GTV. BLADE sequence can be used as an important imaging tool for accurate target delineation in radiotherapy.
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Background: Diffusion-weighted magnetic resonance imaging (DWI) is a valuable tool to narrow down the differential diagnosis of renal masses. Studies have shown that benign renal masses have higher Apparent diffusion coefficient (ADC) value than malignant renal masses. Aim of study was to evaluate the role of diffusion-weighted magnetic resonance imaging in the characterization of renal masses.Methods: The study was conducted in department of Radio diagnosis at ABVIMS and Dr. RML Hospital, New Delhi between June 2017 to March 2019. This was a cross-sectional observational study comprising of 28 patients. Patients found to have renal mass on ultrasound and computed tomography (CT) were evaluated further on 3T siemens Magnetic resonance imaging (MRI) scanner. In addition to routine sequences, DWI using b value of 0,500,1000 s/mm2 sequence was used to study to differentiate benign and malignant renal masses.Results: Of a total of 28 cases, the most common malignant mass was renal cell carcinoma (RCC). Angiomyolipoma (AML) was the most common benign masses. DWI showed low ADC values in most of the malignant masses and high ADC values in most of the benign masses. The cut-off level of ADC value for differentiation among benign and malignant renal masses was 1.08×10-3 mm2/s. DWI-MR findings were correlated with histopathological diagnosis.Conclusion: DWI with ADC measurements are a non-invasive, problem solving tool for characterization of renal masses helping to differentiate malignant from benign masses.
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Objective To evaluate the effect of neoadjuvant androgen deprivation therapy (ADT) for prostate cancer on diffusion weighted imaging base on the pathological results after radical prostatectomy.Methods Medical records of 33 patients diagnosed with prostate cancer and treated with neoadjuvant androgen deprivation therapy and radical prostatectomy between January 2016 and September 2019 at Peking University First Hospital were retrospectively reviewed.Average age of patients was 67.7 (49-81) years old.All of the patients underwent prostate MRI examination before and after neoadjuvant ADT.Results Mean prostate volume after neoadjuvant ADT is 28.5 (6.25-113.76) em3,which decreased significantly by therapy (Z =-4.458,P ＜ 0.05).Apparent diffusion coefficient (ADC) values increased significantly in tumor (1.070 ± 0.325) vs.(0.828 ± 0.291) × 10-3 mm2/s (P ＜ 0.001) and decreased in benign prostatic tissue (P ＜ 0.05).Relative changes in ADC differed significantly between low-median level ISUP group and high level ISUP group (0.315 ± 0.173) vs.(0.164 ± 0.224) × 10-3 mm2/s (P ＜ 0.05),as well as obvious reaction group and focal reaction group(0.278 ± 0.21) vs.(0.094 ± 0.119) × 10-3 mm2/s (P ＜ 0.05).Conclusions There were significant,quantitative measurable changes of ADC value in prostate cancer after neoadjuvant ADT.DWI can be used to assess the efficacy of neoadjuvant ADT for prostate cancer as well as predicting pathological features.
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Background: Magnetic resonance signal intensity of focal liver lesions is affected by numerous pathologic factors. Lesion histologic features, such as cellularity, vascularity, stromal component, and intratumoral necrosis or hemorrhage, strongly affect T1 and T2 relaxation times. Aim and objectives: To assess the lesion characterization potential of MRI by evaluating unenhanced and dynamic gadolinium enhanced sequences, Histopathological correlation of the lesions to explain the major MRI findings and Assessment of the lesions by diffusion weighted imaging and investigating the role of b value in differentiating malignant and benign lesions Materials and methods: The study was done on 42 patients where contrast was given in 38 members. Focal liver lesions were analyzed based on clinical findings, laboratory investigations and MR imaging. Sonographically detected focal lesions were included in the study. Tissue diagnosis (FNAC/ Biopsy), surgery were done in feasible cases. In other cases, where surgery/ tissue diagnosis is not possible, follow up was done (range 3 months - 12 months, average 7.2 months). Results: MRI features of forty two patients with focal liver lesions were studied and morphological features and signal intensities of the masses were described. Contrast study was done in 39 cases. Of the 42 cases, 24 lesions were benign and 18 lesions were malignant. The mean age group ranged from 18 to 74 years with majority between 40 to 60 years. 61% of the lesions were located in right lobe of the liver. Contrast enhancement was done in 39 cases. Contrast enhancement was able to better delineate the cases. Specific pattern of contrast enhancement was typical of certain lesions as Karuna V, R Vikash Babu. Magnetic Resonance Imaging in Focal Liver Lesions with Diffusion Weighted Imaging (DWI) and Pathological Correlation. IAIM, 2019; 6(11): 81-93. Page 82 homogenous early arterial phase enhancement for hepatocellular carcinoma and ring enhancement in arterial phase for metastases. Delayed enhancement was specific for cholangiocarcinoma. Hemangiomas showed peripheral puddling and delayed central enhancement. Diffusion weighted imaging can be used as an additional tool in differentiating benign and malignant focal liver lesions. ADC value using a cut-off of 1.43 X 10 – 3 sec/ mm2 was a useful adjunct for determining benign cystic lesions and hemangiomas from malignant lesions. Conclusion: MRI was able to predict diagnosis in 38 of the 42 tumors. It could suggest the nature of all lesions in benign cysts, hemangiomas, focal nodular hyperplasia and metastases. But it was not possible to achieve a specific diagnosis in two early abscesses, one multifocal hepatocellular carcinoma and one case of regenerative nodules. This accounted for a detection rate of 90%. Thus MR imaging is a powerful tool for the evaluation of focal liver lesions. Pre contrast T1 weighted gradient echo images, T2 weighted images, in phase and out phase imaging, EPI – DWI and gadolinium enhanced T1 weighted images provide accurate characterization of the lesions.
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OBJECTIVE: To systematically review the evaluation of the diagnostic accuracy of pre-treatment apparent diffusion coefficient (ADC) and change in ADC during the intra- or post-treatment period, for the prediction of locoregional failure in patients with head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Ovid-MEDLINE and Embase databases were searched up to September 8, 2018, for studies on the use of diffusion-weighted magnetic resonance imaging for the prediction of locoregional treatment response in patients with HNSCC treated with chemoradiation or radiation therapy. Risk of bias was assessed by using the Quality Assessment Tool for Diagnostic Accuracy Studies-2. RESULTS: Twelve studies were included in the systematic review, and diagnostic accuracy assessment was performed using seven studies. High pre-treatment ADC showed inconsistent results with the tendency for locoregional failure, whereas all studies evaluating changes in ADC showed consistent results of a lower rise in ADC in patients with locoregional failure compared to those with locoregional control. The sensitivities and specificities of pre-treatment ADC and change in ADC for predicting locoregional failure were relatively high (range: 50–100% and 79–96%, 75–100% and 69–95%, respectively). Meta-analytic pooling was not performed due to the apparent heterogeneity in these values. CONCLUSION: High pre-treatment ADC and low rise in early intra-treatment or post-treatment ADC with chemoradiation, could be indicators of locoregional failure in patients with HNSCC. However, as the studies are few, heterogeneous, and at high risk for bias, the sensitivity and specificity of these parameters for predicting the treatment response are yet to be determined.
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Humans , Bias , Carcinoma, Squamous Cell , Diffusion , Epithelial Cells , Head , Magnetic Resonance Imaging , Neck , Population Characteristics , Sensitivity and SpecificityABSTRACT
Objective To explore the value of diffusion kurtosis imaging (DKI) in predicting radiotherapy sensitivity of esophageal cancer from the animal model level.Methods BALB/c nude mice were subcutaneously injected with Eca-109 cell lines to form xenograft tumors.The tumors received a single dose of 15 Gy (6 MV X-rays) in the experimental group or had no any treatment as control.The volume of transplanted tumor,the change of ADC,MK and MD values,and the tumor cell density and necrosis ratio of these two groups were observed at the corresponding time points.Results The growth of xenograft volume in the experimental group was suppressed and it was significantly smaller than that in the control group (t=3.206-6.149,P＜0.05) at the 7th day after radiotherapy.From the 3rd day after radiotherapy,the ADC and MD values of the experimental group were significantly higher than those of the control group,and the MK values was lower than those in the control group (tADC =-11.018--2.049,tMD =-6.609--2.052,tMK =2.492-9.323,P＜0.05).Meanwhile,the tumor cell density of the control group was higher than that of the experimental group,and the proportion of necrosis in the experimental group was higher than that in the control group (tdensity =-8.387--2.239,t is =2.980-17.430,P＜0.05).Conclusions A single large dose radiation could inhibit the growth of xenograft.ADC,MK,MD values changed at the early stage prior to morphological changes of tumor in consistent with the change of cell density and necrosis ratio.DKI has the potential value in predicting radiotherapy sensitivity of esophageal carcinoma.
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Objective To discuss the MRI findings of hepatic epithelioid hemangioendothelioma (EHE).Methods MRI and clinical data of 8 EHE patients confirmed by pathology in PLA General Hospital were retrospectively analyzed.Results 8 patients included 3 male and 5 female.1 patient had single lesion and 7 patients had multiple lesions.A total of 162 lesions were detected and most of the lesions were in the peripheral liver.For T1WI,100 lesions (61.7％) showed slightly low signal,and 62 lesions (38.3％) showed lower signal intensity in the center of the lesion and appeared as "target sign".For T2WI,the center of 29 lesions (17.9％) showed two-loop "target sign",66 lesions (40.7％) showed three-loop "target sign",and 67 lesions (41.4％) showed slightly homogeneous higher signal.For DWI,116 lesions (71.6％) showed halo-like high signal and 46 lesions (28.4％) showed uniform high signal.For dynamic enhancement,the lesions showed slightly enhancement in the arterial phase,and persistent enhancement in portal venous phase,the center of 122 lesions (about 75.3％) showed enhancement and 40 lesions (24.7％) showed no enhancement in delayed phase.1 patient with hepatobiliary specific contrast was enhanced in hepatobiliary phase.“Hepatic capsule depression” was observed in 30 lesions.7 lesions appeared as “lollipop sign”,and were enveloped in 16 lesions.Conclusion MRI,DWI and dynamic contrastenhanced scanning of EHE in liver are characteristic,which is helpful for qualitative diagnosis before surgery.
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Objective To determine the efficacy of primary tumor of esophageal cancer,according to the result of magnetic resonance imaging before and after chemoradiotherapy of esophageal cancer,combined with clinical efficacy evaluation,and to verify the reliable evaluation of the short-term curative effect of magnetic resonance on esophageal cancer,combined with the original CT and esophagogram evaluation criteria.Methods From May 2010 to March 2014,totally 83 patients with esophageal carcinoma treated with 3D-CRT or IMRT were enrolled.The prescribed doses were ranged from 50-64 Gy with median dose of 60 Gy and 1.8-2.0 Gy per fraction,of which 34 of the patients received concurrent chemotherapy of FP or TP.All the patients performed the examinations of DWI,CT scan and esophagogram before and after radiotherapy.The treatment efficacy was evaluated by short-term therapeutic effect evaluation criterion of versions 1989 and 2013 and the hyperintense expression on DWI sequence.Results According to the short-term therapeutic effect evaluation criterion of versions 1989 and 2013 based on the examination of esophagogram and CT scan,45 patients achieved complete remission (CR) after treatment(54.2％) and 38 achieved partly remission(PR) (45.8％) version 1989,while 35 patients achieved CR (42.2％) and 48 achieved PR (57.8％) version vesion 2013.In the two differentcriterions,the local control rate and survival rate of the complete remission group in 1 to 5 years were better than those in the partial remission group.According to the examination of DWI,48 patients' hyperintense disappeared completely at the end of treatment (which was defined to CR),25 patients had a slightly hyperintense expression and 10 patients still had hyperintense expression on DWI sequence (which two defined to PR),the local control and survival rates of the former group were superior to the latter groups (x2 =6.125,11.652,P ＜0.05).The TE results evaluated by DWI and TE evaluation criterion of version 2013 were compared according to Kappa test,as a result,the Kappa coefficient 0.478.According to the examination of esophagogram,CT scan and DW1,25 patients achieved CR and 58 achieved PR in all exams,and the local control and survival rates of the former group were superior to the latter group (x2 =5.559,10.014,P ＜0.05).Conclusions The esophagogram and CT based TE evaluation criterion could well indicate local control status of esophageal cancer,and the examination of DWI could afford visualized and quantifying reference information about the TE of esophageal cancer.The expression of hyperintense at the end of treatment may indicate a high risk of recurrence and metastasis.The therapeutic effect evaluated by esophagogram,CT scan and DWI maybe more objective and more accurate.
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Objective To enhance the standardized operation of multi b value DWI technique when the radio technician detects liver tumors.Methods The operation specifications of multi b value DWI technique applied to liver benign tumors diagnosis were analyzed for MRI conventional examination,MR-DWI scan,MR-DWI image processing.Considerations were also taken on unified detection standard,supervision system,management mechanism and etc.Results Radio technician was improved in operation specification when used multi b value DWI technique to detect liver tumors. Conclusion Radio technician operation specification of multi b value DWI technique has to be strengthened to enhance the clinical efficacy.
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Objective To explore the value of intra-voxel incoherent motion diffusion weighted imaging(IVIM-DWI)in brain perfusion of early hypertensive patients. Methods Totally 36 hypertensive patients and 14 volunteers were recruited and scanned using routine MRI sequences including axial T2WI, T1WI, T2FLAIR, TOF-MRA and IVIM-DWI sequence. Perfusion-related diffusion coefficient (D*) values and perfusion fraction (f) values in various regions were measured separately.The independent sample t test was used to analyze the data.Results Compared with the volunteers,both D*values and f values in lenticular nucleus,thalamus,superior frontal gyrus,occipital lobe,genu of corpus callosum(CC)and posterior horns of periventricular WM, were found to be lower (P<0.05) in hypertensive patients. For other regions, there were no significant difference(P>0.05).Conclusion IVIM-DWI has the ability to detect subtle brain perfusion abnormalities at early stages of hypertension.It has an important value to the prevention and treatment of hypertensive encephalopathy.
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Objective To evaluate the value of Alberta Stroke Program Early CT Score on diffusion weight-ed imaging(DWI-ASPECTS)in predicting the leptomeningeal collateral circulation(LMA)compensation of isch-emic stroke with middle cerebral artery stenosis or occlusion after intravenous thrombolysis. Methods A total of 178 patients with ischemic stroke confirmed as severe middle cerebral artery stenosis or occlusion by imaging were enrolled in the study.All the patients were treated by rt-PA intravenous thrombolysis.The baseline clinical date, DWI-ASPECTS,mRS and NIHSS were collected. LMA was assessed by cranio-cervical CTA. Results Compared with the poor collateral circulation group,the triglyceride level and DWI-ASPECTS were significantly increased in good collateral circulation group(P<0.05).The proportion of hypertension,NIHSS score,mRS score in good col-lateral circulation group were significantly lower than those in the poor collateral circulation group(P < 0.05). Compared with the poor collateral circulation group,insula,the ASPECTS areas M1 to M4,M6 and insula showed significantly fewer infarctions in good collateral circulation group(P<0.05).ROC analysis showed the area under ROC curve(AUC)of DWI-ASPECTS to predict LMA compensation were 0.932,the cutoff point of DWI-ASPECTS was 7.5.the sensitivity and specificity were 81.% and 94.1%.Conclusions The tissue protective role of good lepto-meningeal collateralization seems to be more pronounced in cortical and subcortical areas M1 to M4,M6 and the in-sula.DWI-ASPECTS can effectively predict the collateral circulation compensation in patients with acute middle ce-rebral artery infarction.