IRM corps entier 1, 5 T avec séquence de diffusion dans l'évaluation du cancer à propos de 124 cas / 1. 5 T Whole Body MRI with diffusion sequence in cancer assessment about 124 cases

L'IRM corps entier de diffusion 1,5T est une technique d'imagerie qui fournit des renseignements aussi bien morphologique que fonctionnel avec de nombreuses indications notamment dans les pathologies cancéreuses. Objectif: Faire le bilan d'activité de l'IRM corps entier en insistant sur son apport dans la pathologie cancéreuse. Méthodologie:Etude transversale descriptive avec collecte rétrospective des donnéesincluant les patients ayantréalisé une IRM corps entier pourtumeur maligne sur une période de quatre ans. La saisie et l'analyse des données ont été réalisées grâce aux logiciels Epi Info.Résultats:31,19% des patients avaient un âge compris entre 61 et 70 ans. Le cancer de la prostate était le plus représenté avec 34,68% suivi du cancer du sein 31,45%. L'IRM corps entier était réalisée pour le bilan d'extension dans 39,52% et dans 37,10% pour un bilan d'évolutivité. Les localisations métastatiques étaient observées dans 49% des cas avec une atteinte prépondérantede l'étage abdomino-pelvien 72,13%. Les localisations métastatiques osseuses étaient de 73,77%,hépatiques 26,23% et pulmonaire 14,75%. Les atteintes ganglionnaires de 57,14%. Une progression tumorale a été observée chez 53,33% des patients lors du suivi.Conclusion: L'IRM corps entier permet une fine analyse dans l'évaluation de la pathologie cancéreuse pour l'extension tumorale, la réponse thérapeutique et la recherche de cancer primiti

1.5T whole-body diffusion MRI is imaging that provides both morphological and functional information.It presents several indicationsparticularly in oncology. Objective: Assess the activity of whole-body MRI, emphasizing its contribution to oncologyMethodology:Descriptive retrospective study of patients who had undergone whole-body MRIfor malignancy over a four-year period. Data entry and analysis were performed using Epi Info software.Results:31.19% of patients were between 61 and 70 years old. Prostate cancer was the most represented with 34.68% followed by breast cancer 31.45%.Whole-body MRI was requested for an extension assessment in 39.52% and 37.10% for progress assessment. It revealed metastatic abnormalities in 49%. Abdomino-pelvic region was the most affected area with 72.13%. Metastatic organ involvement was predominantly in the bone 73.77%, followed by the liver 26.23% and the lung14.75%. Lymph node involvement was 57.14%.Tumor progression was observed in 53.33% of patients during follow-up.Conclusion:Whole body MRI allows a fine analysis in the evaluation of the cancerous pathology for the tumor extension, the therapeutic response and the search for primary cancer

Utilidad de la secuencia de susceptibilidad como predictor de penumbra en la isquemia cerebral aguda / Utility of susceptibility sequence as a predictor of penumbra in acute cerebral ischemia

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.

MRI as a Diagnostic Tool for the Determination of Acute Ischaemic Stroke: A Study in a Tertiary Care Hospital

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.

Value of dynamic subtraction MRI in assessing HCC response to image-guided loco-regional therapy

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

Value of Reduced Field-of-view DWI in Quantitative Assessment of Axial Spondyloarthritis / 中山大学学报(医学科学版)

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.

Comparison of ZOOMit-DWI sequence and conventional DWI sequence in endometrial cancer / 中南大学学报(医学版)

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.

Correlation Between Apparent Diffusion Coefficient and IDH-1/1p19q Genotype of Glioma / 肿瘤防治研究

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.

Fluid?attenuated inversion recovery diffusion?weighted imaging (DWI) for evaluating chemotherapy response in patients with acute leukemia: Comparison with conventional DWI

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

Diferenciación de la patología tumoral musculoesquelética benigna y maligna utilizando la técnica de difusión con resonancia magnética / Differentiation of benign and malignant musculoskeletal tumor pathology using the diffusion technique with magnetic resonance imaging

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.

Tissue Window versus Time Window? A Review of Patients Receiving Extended Hours Thrombolysis Guided By DWI-FLAIR Mismatch : Case Series

@#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.

Value of MRI T 2WI-TSE-BLADE sequence in accurately delineating the gross tumor volume of esophageal carcinoma based on pathological specimens / 中华放射肿瘤学杂志

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.

Role of diffusion: weighted magnetic resonance imaging in evaluation of renal masses

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.

Evaluation and prediction of therapeutic response to neoadjuvant androgen deprivation therapy for prostate cancer by diffusion weighted imaging / 中华泌尿外科杂志

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.

Diffusion-weighted Magnetic Resonance Imaging for Predicting Response to Chemoradiation Therapy for Head and Neck Squamous Cell Carcinoma: A Systematic Review

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.

Experimental study of diffusion kurtosis imaging in predicting radiotherapy sensitivity of esophageal carcinoma / 中华放射医学与防护杂志

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.

Magnetic Resonance Imaging in Focal Liver Lesions with Diffusion Weighted Imaging (DWI) and Pathological Correlation

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.

Diffusion-Weighted MR Imaging of Unicystic Odontogenic Tumors for Differentiation of Unicystic Ameloblastomas from Keratocystic Odontogenic Tumors

OBJECTIVE: Differentiating unicystic ameloblastomas from keratocystic odontogenic tumors (KCOT) is necessary for the planning of different treatment strategies; however, it is difficult based on conventional CT and MR sequences alone. The purpose of this study was to investigate the utility of diffusion-weighted imaging (DWI) and apparent diffusion coefficients (ADCs) in the differentiation of the two tumors. MATERIALS AND METHODS: We prospectively studied 40 patients with odontogenic cysts and tumors of the maxillomandibular region using conventional MR imaging and DWI. ADCs were measured using 2 b factors (500 and 1000). RESULTS: Unicystic ameloblastomas (n = 11) showed free diffusion on DWI and a mean ADC value of 2.309 ± 0.17 × 10-3 mm2/s. KCOT (n = 15) showed restricted diffusion on DWI with a mean ADC value of 0.923 ± 0.20 × 10-3 mm2/s. The ADC values of unicystic ameloblastomas were significantly higher than those of KCOT (p < 0.001, Mann-Whitney U-test). An ADC cut-off value of 2.0 × 10-3 mm2/s to differentiate KCOT and unicystic ameloblastomas resulted in a 100% sensitivity and 100% specificity. Dentigerous cysts (n = 3) showed restricted diffusion on DWI and similar ADC values (1.257 ± 0.05 × 10-3 mm2/s) to those of KCOT. CONCLUSION: Diffusion-weighted imaging and ADC determination can be used as an adjuvant tool to differentiate between unicystic ameloblastomas and KCOT, although the ADC values of dentigerous cysts overlap with those of KCOT.

The investigation of using diffusion-weighted magnetic resonance imaging technologies to evaluate the therapeutic effect of esophageal primary carcinoma treatment with chemoradiotherapy / 中华放射医学与防护杂志

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.

Detection of hypothalamic infarction in intraluminal middle cerebral artery occlusion model rat by DWI scanning / 上海交通大学学报（医学版）

Objective: To detect and evaluate the hypothalamic infarction in middle cerebral artery occlusion (MCAO) model rat. Methods: For 15 Sprague-Dawley rats weighed 200-250 g, aged 6-8 months, their right middle cerebral artery was occluded for 90 min by a silicon-coated 4-0 nylon filament and reperfused. Sprague-Dawley rats underwent diffusion weighted MR imaging (DWI) scanning (at 1 h and 24 h after reperfusion) and 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining (at 24 h after reperfusion) to determine the hypothalamic and cerebral infarct volume. The relationship between hypothalamic infarct volume and cerebral infarction volume was analyzed by DWI scanning. The results of TTC staining were compared with those of 24 h DWI scanning. Results: Fifteen Sprague-Dawley rats successfully received intraluminal MCAO/reperfusion procedures. The incidences of hypothalamic infarction on brain DWI scanning and TTC staining were 100% and 40% at 24 h after reperfusion, respectively. Therefore, DWI scanning was more sensitive than TTC staining to detect hypothalamic injury (P=0.001). The hypothalamic infarct volume on DWI scanning was (8.59±2.89) mm3 and (11.65±3.19) mm3 at 1 h and 24 h after reperfusion, respectively. On DWI scanning, hypothalamic and cerebral infarct volume at 24 h after reperfusion were correlated with each other significantly (r=0.573, P=0.025), so were the increases of hypothalamic and cerebral infarct volume (r=0.554, P=0.032) from 1 h to 24 h. Conclusion: DWI scanning was more sensitive than TTC staining to detect hypothalamic injury in intraluminal transient MCAO model. Hypothalamic and cerebral infarct volume were correlated with each other.

Radio technician operation specification of multi b value DWI technique applied to liver tumor detection / 医疗卫生装备

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.