Role Of Diffusion-weighted Imaging Research Articles

The role of diffusion-weighted imaging in the detection of hepatic metastases from colorectal cancer: A comparison with unenhanced and Gd-EOB-DTPA enhanced MRI

ObjectivesTo compare the role of DWI vs. gadoxetic-acid-disodium enhanced MRI in the detection of colorectal hepatic metastases. MethodsFifty-four patients with 115 hepatic metastases were included in this retrospective study, approved by the Ethical Board. All patients underwent intraoperative-ultrasound and surgical resection within two weeks after MRI. Images were grouped in 4 sets, which were analyzed by two radiologists in different sessions: unenhanced T1-T2w (set A), set A plus DWI (set B), set A plus gadoxetic-acid-disodium (set C), set A plus DWI plus gadoxetic-acid-disodium (set D). For each set, metastases presence/size/site was reported. Interobserver agreement and statistical significance were assessed by Cohen’s kappa and Mc-Nemar’s test, respectively. ResultsReaders’ agreement was always very good (k>0.80). Mean sensitivity values were 84.3/92.1/95.6/97.3% for set A/B/C/D, respectively. Mean specificity, positive predicted, negative predicted, and accuracy values strongly and progressively increased in the various set too: from 62.5% (set A) to 85.0% as for specificity, from 92.8% to 97.3% as for positive predicted value, from 41.0% to 85.1% as for negative predicted value, and from 81.1% to 95.5% as for accuracy.For each reader from set A to D, the number of false negatives progressively decreases. ConclusionsFor both readers, DWI improved all statistical parameters in the unenhanced examinations, as for nodules either smaller or greater than 1cm, while in the EOB-enhanced examinations DWI prevalently increased specificity/negative predictive value.

The Role of Diffusion-Weighted Imaging (DWI) in Locoregional Therapy Outcome Prediction and Response Assessment for Hepatocellular Carcinoma (HCC): The New Era of Functional Imaging Biomarkers.

Reliable response criteria are critical for the evaluation of therapeutic response in hepatocellular carcinoma (HCC). Current response assessment is mainly based on: (1) changes in size, which is at times unreliable and lag behind the result of therapy; and (2) contrast enhancement, which can be difficult to quantify in the presence of benign post-procedural changes and in tumors presenting with a heterogeneous pattern of enhancement. Given these challenges, functional magnetic resonance imaging (MRI) techniques, such as diffusion-weighted imaging (DWI) have been recently investigated, aiding specificity to locoregional therapy response assessment and outcome prediction. Briefly, DWI quantifies diffusion of water occurring naturally at a cellular level (Brownian movement), which is restricted in multiple neoplasms because of high cellularity. Disruption of cellular integrity secondary to therapy results in increased water diffusion across the injured membranes. This review will provide an overview of the current literature on DWI therapy response assessment and outcome prediction in HCC following treatment with locoregional therapies.

Reversible Focal Splenial Lesion on Diffusion-Weighted MRI in Sulfonylurea Intoxication.

Hypoglycemic brain injury is usually reversible, and partial recovery or mortality depends on the affected area. Diffusion-weighted imaging (DWI) may be useful in predicting the prognosis according to the site of involvement. Isolated lesions of the splenium of corpus callosum (SCC) in hypoglycemic brain injury are very rare, and DWI findings of a reversible lesion of the SCC due to deep hypoglycemia associated with sulfonylurea intoxication has been reported only once in the literature. We report the case of a 15-year-old girl admitted to the emergency department who had attempted suicide using sulfonylurea and subsequently went into a coma. The patient had no known previous disease. Except for a blood glucose level of 10 mg/dl, all other blood laboratory tests were normal. DWI performed two hours after admission showed diffusion restriction in the SCC. After receiving treatment for 24 hours, the patient became conscious, and her blood glucose level returned to normal. Two days later, complete resolution of the SCC lesion was revealed by control DWI. We discuss both the DWI findings of the reversible SCC lesion due to hypoglycemic brain injury resulting from sulfonylurea intoxication and the role of DWI in predicting the clinical outcome.

Accuracy of magnetic resonance imaging in differentiating between benign and malignant vertebral lesions: Role of Diffusion-weighted imaging, in-phase/opposed-phase imaging and apparent diffusion coefficient

ObjectiveTo determine the ability of MRI to distinguish between benign and malignant vertebral lesions. Materials and methodsWe included 85 patients and studied a total of 213 vertebrae (both pathologic and normal). For each vertebra, we determined whether the lesion was hypointense in T1-weighted sequences and whether it was hyperintense in STIR and in diffusion-weighted sequences. We calculated the in-phase/out-of-phase quotient and the apparent diffusion coefficient for each vertebra. We combined parameters from T1-weighted, diffusion-weighted, and STIR sequences to devise a formula to distinguish benign from malignant lesions. ResultsThe group comprised 60 (70.6%) women and 25 (29.4%) men with a mean age of 67±13.5 years (range, 33–90 y). Of the 85 patients, 26 (30.6%) had a known primary tumor. When the lesion was hypointense on T1-weighted sequences, hyperintense on STIR and diffusion-weighted sequences, and had a signal intensity quotient greater than 0.8, the sensitivity was 97.2%, the specificity was 90%, and the diagnostic accuracy was 91.2%. If the patient had a known primary tumor, these values increased to 97.2%, 99.4%, and 99%, respectively. ConclusionBenign lesions can be distinguished from malignant lesions if we combine the information from T1-weighted, STIR, and diffusion-weighted sequences together with the in-phase/out-of-phase quotient of the lesion detected in the vertebral body on MRI.

Artery of Percheron occlusion: role of diffusion-weighted imaging in the early diagnosis

Artery of Percheron occlusion: role of diffusion-weighted imaging in the early diagnosis

Role of diffusion-weighted imaging in acute stroke management using low-field magnetic resonance imaging in resource-limited settings

A variety of imaging modalities exist for the diagnosis of stroke. Several studies have been carried out to ascertain their contribution to the management of acute stroke and to compare the benefits and limitations of each modality. Diffusion-weighted imaging (DWI) has been described as the optimal imaging technique for diagnosing acute ischemic stroke, yet limited evidence is available on the value of DWI in the management of ischemic stroke with low-field magnetic resonance (MR) systems. Although high-field MR imaging (MRI) is desirable for DWI, low-field scanners provide an acceptable clinical compromise which is of importance to developing countries posed with the challenge of limited availability of high-field units. The purpose of this paper was to systematically review the literature on the usefulness of DWI in acute stroke management with low-field MRI scanners and present the experience in Nigeria.

Graves' ophthalmopathy: the role of diffusion-weighted imaging in detecting involvement of extraocular muscles in early period of disease.

To evaluate involvement of the extraocular muscle (EOM) using diffusion-weighted imaging (DWI), to determine whether there is correlation with conventional orbital MRI and apparent diffusion coefficient (ADC) values in patients with Graves' ophthalmopathy (GO). 35 patients known clinically with GO and 21 healthy controls were studied. Patients were assessed with clinical activity scores. All subjects underwent conventional MRI and DWI study. Involvement of the EOM was evaluated. The patients were classified as involved or uninvolved on orbital MRI and their ADC values in DWI compared. There was significant difference in the mean ADC value of all the EOMs in patients vs controls. The ADC values of all the EOMs were higher in patients. There were significant differences in ADC values between uninvolved muscles on conventional MRI and controls for the MR, SR and LR. There was no significant difference in ADC value between the two groups when considering the IR. ADC values of medial, lateral and superior rectus muscles were increased. Increased ADC values of the EOM in patients with GO suggest that EOM damage begins at a very early stage before being detected on routine orbital MRI. The routine MRI with DWI sequence will be a useful adjunct in the selection of a group of patients most likely to benefit from early treatment. This study can help to evaluate the involvement of GO in early period with MRI added DWI.

Role of diffusion-weighted imaging, apparent diffusion coefficient and correlation with hepatobiliary phase findings in the differentiation of hepatocellular carcinoma from dysplastic nodules in cirrhotic liver.

To investigate the utility of diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) and the correlation with hepatobiliary phase (delayed phase imaging, DPI) findings in the differentiation of cirrhotic hepatocellular nodules. Forty-three patients with 53 pathology-proven nodules (29 hepatocellular carcinomas (HCCs), 13 high-grade (HGDNs) and 11 low-grade dysplastic nodules (LGDNs); mean size 2.17 cm, range 1-4 cm), who underwent liver MRI with DWI and DPI sequences, were retrospectively reviewed. Lesions were classified as hypointense, isointense, or hyperintense relative to the adjacent liver parenchyma. ADC of each nodule, of the surrounding parenchyma, and lesion-to-liver ratio were calculated. Hyperintensity versus iso/hypointensity on DWI, hypointensity versus iso/hyperintensity on DPI, and the mean lesion-to-liver ratio showed a statistically significant difference both between HCCs versus DNs and between "HCCs + HGDNs" versus LGDNs (p < 0.05); sensitivity, specificity, and accuracy for the diagnosis of "HCCs + HGDNs" were 96.8 %, 100 %, 97.4 % respectively when combining hyperintensity on DWI and hypointensity on DPI, and 90.9 %, 81.0 %, 83.6 % respectively when lesion-to-liver ratio was <0.95. Hyperintensity on DWI, especially in association with hypointensity on DPI, and low lesion-to-liver ratios should raise the suspicion of HCC, or at least of HGDN, thus helping the characterization of atypically enhancing lesions. • Usefulness of DWI and ADC is shown in differential diagnosis of cirrhotic nodules. • Correlation of DWI with DPI improves differential diagnosis of cirrhotic nodules. • Characterization of atypically enhancing lesions becomes more confident.

Role of diffusion-weighted imaging as an adjunct to contrast-enhanced breast MRI in evaluating residual breast cancer following neoadjuvant chemotherapy

ObjectiveTo investigate whether the addition of diffusion-weighted imaging (DWI) to dynamic contrast-enhanced MRI (DCE-MRI) improves diagnostic performance in predicting pathologic response and residual breast cancer size following neoadjuvant chemotherapy. Materials and methodsA total of 78 consecutive patients who underwent preoperative breast MRI with DWI following neoadjuvant chemotherapy were enrolled. DWI was performed on a 1.5T system with b values of 0 and 750s/mm. or on a 3T system with b values of 0 and 800 or 0 and 1000s/mm. The images on DCE-MRI alone, DWI alone, and DCE-MRI plus DWI were retrospectively reviewed. We evaluated the diagnostic performances of the three MRI protocols for the detection of residual cancer. The tumor size as predicted by MRI was compared with histopathologic findings. Apparent diffusion coefficient (ADC) values were also compared between the groups with and without residual cancer. ResultsOf the 78 patients, 59 (75.6%) had residual cancer. For detection of residual cancer, DCE-MRI plus DWI had higher specificity (80.0%), accuracy (91.0%), and PPV (93.2%) than DCE-MRI or DWI alone (P=0.004, P=0.007, and P=0.034, respectively). The ICC values for residual cancer size between MRI and histopathology were 0.891 for DCE-MRI plus DWI, 0.792 for DCE-MRI, and 0.773 for DWI. ADC values showed no significant differences between residual cancer and chemotherapeutic changes (P=0.130). ConclusionsThe addition of DWI to DCE-MRI significantly improved diagnostic performance in predicting pathologic response and residual breast cancer size after neoadjuvant chemotherapy.

Role of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) in differentiating between benign and malignant breast lesions

ObjectiveTo assess the role of DWI and ADC in differentiating between benign and malignant breast lesions. Materials and methods51 patients (age range 24–66years; mean age 48years) were included in our study. MRI was done using bilateral fat-suppressed T2- weighted fast spin-echo, STIR, axial T1-weighted fast spin-echo. DWI series were acquired using echo planar imaging pulse sequences incorporated with diffusion gradients and finally dynamic contrast enhancement study was done. ResultsSixty three lesions were detected in 51 patients included in our study. Twenty one lesions were malignant, three lesions were intermediate and twenty two lesions were fibroadenoma according to the final histopathological study and seventeen lesions were breast cysts. A total of 21 lesions showed lower ADC values than benign lesions and were in the range of 0.76–1.29×10−3mm2/s and were diagnosed as malignant breast lesions. The sensitivity and specificity for DWI in the differentiating malignant from benign breast lesions were calculated and showed 95.4% and 97.5%, respectively. ConclusionDWI is easy to obtain in short scan time and easy to evaluate, and ADC values can differentiate between benign and malignant breast lesions with high sensitivity and specificity.

Role of diffusion-weighted imaging in differentiating benign and malignant pediatric abdominal tumors

Solid malignant tumors are more highly cellular than benign lesions and hence have a restricted diffusion of water molecules. To evaluate whether diffusion-weighted MR imaging (DWI) can differentiate between benign and malignant pediatric abdominal tumors. We retrospectively analyzed DWI scans of 68 consecutive children with 39 benign and 34 malignant abdominal masses. To calculate the apparent diffusion coefficient (ADC) maps and ADC values, we used 1.5-T sequences at TR/TE/b-value of 5,250-7,500/54-64/b = 0, 500 and 3-T sequences at 3,500-4,000/66-73/b = 0, 500, 800. ADC values were compared between benign and malignant and between data derived at 1.5 tesla (T) and at 3 tesla magnetic field strength, using the Mann-Whitney-Wilcoxon test, ANOVA and a receiver operating curve (ROC) analysis. There was no significant difference in ADC values obtained at 1.5 T and 3 T (P = 0.962). Mean ADC values (× 10(-3) mm(2)/s) were 1.07 for solid malignant tumors, 1.6 for solid benign tumors, 2.9 for necrotic portions of malignant tumors and 3.1 for cystic benign lesions. The differences between malignant and benign solid tumors were statistically significant (P = 0.000025). ROC analysis revealed an optimal cut-off ADC value for differentiating malignant and benign solid tumors as 1.29 with excellent inter-observer reliability (alpha score 0.88). DWI scans and ADC values can contribute to distinguishing between benign and malignant pediatric abdominal tumors.

Role of diffusion-weighted imaging in early ankylosing spondylitis

Background With the advanced MRI techniques, pathologic features can be detected at an early stage and quantitatively evaluated, resulting in the advantages of early diagnosis and prompt treatment. This study aimed to determine the value of diffusion-weighted MR imaging (DWI) in detection of early ankylosing spondylitis (AS) and investigate the characteristic manifestations of AS on whole body DWI (WB-DWI). Methods Twenty patients with the diagnosis of early AS, twenty patients with low back pain (LBP), and twenty-five healthy volunteers were included in this study. The subchondral bone apparent diffusion coefficients (ADC) among these groups in the bilateral ilia and sacrum along the sacroiliac joints were compared. An independent sample t-test was utilized to analyze ADC value differences among groups. P-values less than 0.05 denoted statistical significance. The mean ADC values of focal DWI lesions in AS patients were also measured. Whole body diffusion-weighted imaging was performed in fifteen additional AS patients, and analyzed with MIP and MPR techniques in comparison to conventional MR images in order to evaluate the ability to detect AS lesions with whole body DWI. Results Mean ADC values in AS patients were (0.518±0.122)×10-3 mm2/s in the ilium and (0.503±0.168)×10-3 mm2/s in the sacrum. These were significantly greater than the values measured in the ilium and sacrum of LBP patients, (0.328±0.053)×10-3 mm2/s in the ilium and (0.311±0.081)×10-3 m2/s in the sacrum, and control group, (0.325±0.015)×10-3 mm2/s in the ilium and (0.318±0.011)×10-3 mm2/s in the sacrum respectively. No statistically significant differences were found between LBP group and control group. The mean ADC value of focal DWI lesions in early AS patients was (0. 899±0.265)×10-3 mm2/s, which was significantly higher than that of adjacent normal-appearance areas ((0.454±0.079)×10-3 mm2/s). WB-DWI detected abnormalities in the 15 additional AS patients both within the sacroiliac joints and at other sites, corresponding to the clinical symptoms of the patients. The mean ADC value of focal DWI lesions of this patient cohort was (1.286±0.311)×10-3 mm2/s in the sacrum and (1.220±0.299) ×10-3 mm2/s in the ilium. Conclusions Subchondral marrow ADC values of subchondral marrows near the sacroiliac joints allow for the differentiation of patients with early AS from normal volunteers and LBP patients. Combined with post-processing techniques such as MIP and MPR, WB-DWI allows for the comprehensive assessment of AS patients, an evaluation potentially helpful in determining prognosis and following the therapeutic response.

Role of Diffusion-Weighted Imaging as a Prognostic Indicator in Acute Hypoxic Encephalopathy

Background: Diffusion-weighted image (DWI) might be useful to predict the prognosis of acute hypoxic encephalopathy. The aim of our study was to test whether the early change and extent of DWI abnormalities can be an indicator of the clinical outcome of hypoxic encephalopathy. Methods: Forty-four patients who were diagnosed as hypoxic encephalopathy due to the cardiorespiratory arrest were retrospectively identified. Clinical variables were determined, and the DWI abnormalities were counted by four areas: cortex, subcortical white matter, cerebellum and deep grey matter, and were divided into three groups by the extent of lesions. Prognosis was classified as 'poor' (Glasgow coma scale (GSC) at 30 days after arrest <9 or death) and 'good' (GSC at 30 days after arrest ≥9). Results: GCS at day 3 (p<0.001), presence of seizure (p=0.01), and presence of lesion (p<0.001) were significantly different in prognosis, but statistically there is no association with the extent of lesions and prognosis (p=0.26). Conclusions: Presence of early DWI changes could predict the clinical outcome of hypoxic encephalopathy after cardiorespiratory arrest.

Role of diffusion-weighted imaging with ADC mapping and in vivo 1H-MR spectroscopy in thyroid nodules

PurposeTo evaluate the role of the combined techniques of apparent diffusion coefficient (ADC) generated from diffusion-weighted magnetic resonance (MR) imaging (DWI) and metabolite spectrum acquired by magnetic resonance spectroscopy (MRS) in differentiating benign from malignant thyroid nodules. Materials and methodsThirty-seven patients with 56 thyroid nodules were evaluated with conventional MRI (T1- & T2-WI), DWI (b value 0.500s/mm2; ADC values were calculated for the thyroid nodules), and MRS (for the presence or absence of choline peak). The ADC values and MRS findings were correlated with the histopathological results. ResultsThe mean ADC of the malignant thyroid nodules (0.89±0.27×10−3mm2/s) was significantly lower than that of the mean ADC of the benign thyroid nodules (1.85±0.24×10−3mm2/s) (p value <0.0001). ADC value of 1.5×10−3mm2/s was used as a cut-off value for differentiation benign from malignant thyroid nodules. The sensitivity, specificity, PPV&NPV of DWI in differentiating benign from malignant thyroid nodules were 94%, 95%, 94% & 95%, respectively (Kappa test 0.84, p value <0.0001), whereas they were 94.7%, 89.2%, 81.8% & 97.1% (Kappa test 0.8, p value <0.0001) with MRS, and 96%, 100%, 100% & 97% (Kappa test 0.96, p value <0.0001) with both DWI and MRS. ConclusionBoth DWI and MRS are useful diagnostic modalities for characterization and differentiation between benign and malignant thyroid nodules. Our preliminary results showed that combination of DWI with calculated ADC values and metabolite spectrum acquired by MRS add more information to MRI and should be considered as an additional and complementary tool to conventional MRI for differentiating benign from malignant thyroid nodules.

Does Diffusion Tensor Imaging-Based Tractography at 3 Months of Age Contribute to the Prediction of Motor Outcome After Perinatal Arterial Ischemic Stroke?

After perinatal arterial ischemic stroke, diffusion-weighted imaging (DWI) and early evaluation of spontaneous motor behavior can be used to predict the development of unilateral motor deficits. The aim of this study was to investigate whether diffusion tensor imaging-based tractography at 3 months of age contributes to this prediction. Twenty-two infants with unilateral perinatal arterial ischemic stroke were included and scanned during the neonatal period. DWI was used to assess restricted diffusion in the cerebral peduncle. At the age of 3 months, diffusion tensor imaging-based tractography of the corticospinal tracts was performed along with assessment of the movement repertoire. The role of DWI, diffusion tensor imaging, and motor assessment in predicting unilateral motor deficits were compared by calculating the positive and negative predictive values for each assessment. Eleven infants (50%) showed abnormal motor behavior at 3 months with subsequent development of unilateral motor deficits in 8 as determined at follow-up (9-48 months, positive predictive value 73%). Diffusion tensor imaging-based tractography correctly predicted the development of unilateral motor deficits in all 8 infants (positive predictive value 100%). A diagnostic neonatal DWI was available in 20 of 22 (91%) infants. Seven infants showed an abnormal DWI, resulting in unilateral motor deficits in 6 infants (positive predictive value 86%). All assessments had a negative predictive value of 100%. Diffusion tensor imaging-based tractography at 3 months can be used to predict neurodevelopmental outcome after perinatal arterial ischemic stroke. It has a similar predictive value as DWI in the neonatal period and can especially be of additional value in case of an indecisive neonatal DWI or unexpected abnormal early motor development.

Perineural trigeminal nerve abscess secondary to Mucor sinusitis: Serial diffusion-weighted MRI and literature review

Perineural extension of rhinocerebral zygomycosis is rare. The role of diffusion-weighted imaging (DWI) in perineural extension and abscess formation within the nerve has not yet been reported in the literature. This is the first case report highlighting the role of DWI in the perineural extension of zygomycosis. We discuss the differential diagnosis and review the literature.

Neuroimaging of pediatric brain infections

Neuroimaging plays an important and growing role in the diagnosis and therapeutic management of pediatric brain infections. This article describes the spectrum of imaging findings associated with major pediatric viral and bacterial brain infections, outlining the role of current imaging technology in the differential diagnoses of brain injury, detection of complications and therapy monitoring. MRI is the tool of choice in the evaluation of brain infections and particular attention is devoted to the role of diffusion-weighted imaging and magnetic resonance spectroscopy. This article considers viral and bacterial infection in their different modalities of presentation as congenital, acute and subacute/chronic disease. With regard to congenital infections, the growing role of fetal MRI as a valuable complement to ultrasound in the prenatal assessment of brain damage is emphasized.

Contributions of Diffusion-Weighted Imaging to Fetal and Neonatal Imaging

Diffusion-weighted imaging has contributed to our understanding of fetal and neonatal brain development. This article will review the role of diffusion-weighted imaging and diffusion tensor imaging in fetuses and neonates, focusing primarily on normal brain developmental processes and then on pathologic processes that can be characterized using diffusion tensor imaging.

Role of diffusion-weighted imaging in evaluating therapeutic efficacy after transcatheter arterial chemoembolization for hepatocellular carcinoma

The decision to repeat transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) is based on correct evaluation of response to therapy. The purpose of this study was to investigate whether apparent diffusion coefficient (ADC), a quantitative parameter of diffusion-weighted imaging (DWI), can predict early HCC recurrence after TACE. Results obtained using this method were compared with those using iodized-oil computed tomography (CT). DWI was performed on 25 patients with 36 HCCs before and 5-7 days after TACE to calculate the ADC of HCC. Patients were also evaluated with iodized-oil CT immediately after TACE. Contrast-enhanced CT was performed 3 months after TACE to confirm early relapse of HCC lesion. After TACE, the percent change in ADC (%ADC) from before to after therapy was significantly increased in non-relapsed lesions (85.2+/-12.4%) compared to relapsed lesions (8.0+/-56.7%, p=0.0004). However, no difference in area under the curve was seen for receiver operating characteristic analysis to predict early relapse after TACE between %ADC from DWI (95% confidence interval, 0.743-1.026) and iodized-oil CT (95% confidence interval, 0.703-1.016). ADC from DWI can evaluate the efficacy of TACE for HCC as effectively as iodized-oil CT, and may help in deciding whether to repeat TACE.

Spinal Cord Infarction Due to Fibrocartilaginous Embolization: The Role of Diffusion Weighted Imaging and Short-Tau Inversion Recovery Sequences

Fibrocartilaginous embolization is a rare cause of ischemic myelopathy caused by embolization of intersomatic disk nucleus pulposus into spinal vasculature during Valsalva-like maneuvers. Diagnostic criteria are based on patient's clinical history, magnetic resonance evidence of T2-hyperintense spinal cord lesion, and exclusion of other causes of ischemic myelopathy. These criteria do not take into account the development of magnetic resonance techniques able to enhance signal abnormalities within the neighboring intersomatic disc or vertebral body and to early characterize central nervous system lesions according to the presence of cytotoxic edema. We present 2 pediatric cases of progressive paraplegia attributed to fibrocartilaginous embolization in which short-tau inversion recovery and diffusion-weighted imaging sequences played a pivotal role showing the ischemic nature of spinal cord lesions. Due to its specificity, diffusion-weighted imaging should be included in the magnetic resonance criteria of fibrocartilaginous embolization and in standard magnetic resonance analysis when dealing with acute transverse myelopathy.