Enhanced T2 Star-weighted Angiography Research Articles

Application of Quantitative Susceptibility Mapping in the Assessment of Iron Content in Brain Regions of Normal Children.

We evaluated brain iron content in a healthy pediatric population using quantitative susceptibility mapping (QSM). From June 2018 to December 2019, healthy subjects aged 2-18 years old (200 males, 200 females) with no anatomical abnormalities were assessed. All of the children underwent 3D T1 anatomical MRIs in addition to the sequence scans of enhanced T2 star-weighted angiography (ESWAN). The ESWAN sequence images were obtained with software to attain quantitative susceptibility mapping of the entire brain. The magnetic susceptibility values in the same brain region were compared across different age groups. The magnetic susceptibility values expressed in the same age group were compared across sexes, brain sides, and brain regions. The magnetic susceptibility value of each brain region increased with age, and the magnetic susceptibility value expressed by each brain region demonstrated a positive correlation with the children's age (r=0.63, P<0.05). No dramatic difference in magnetic susceptibility was observed between the brain's left side and right side in the children within the age range ≥2-<6; however, among the children within the age range ≥6-<18, the magnetic susceptibility values expressed by the left putamen nucleus, globus pallidus, and substantia nigra were higher than those expressed by the same regions on the right side (P<0.05). Quantitative susceptibility mapping can be used to evaluate the content of iron in each brain region of normal children.

The protective role of cigarette smoking against Parkinson's disease via moderation of the interaction between iron deposition in the nigrostriatal pathway and clinical symptoms.

Although cigarette smoking is a risk factor for multiple disorders, it has long been thought to protect against Parkinson's disease (PD). Quantitative susceptibility mapping (QSM) is a novel magnetic resonance imaging (MRI)-based technique for assessing iron accumulation in vivo that has been widely applied in PD studies. This study aimed to investigate how cigarette smoking affects clinical performance of PD using quantified iron deposition as a proxy for PD pathology. In this observational study, we enrolled 35 male PD patients and 47 male healthy controls (HCs) and divided them into four groups. We performed an enhanced T2 star-weighted angiography (ESWAN) MRI sequence to measure the iron content of the nuclei within the nigrostriatal pathway. With the age and total intracranial volume (TIV) controlled as covariates, we performed inter-group comparisons of QSM values and moderation analyses for PD patients using smoking status and the smoking index (SI), respectively, as moderator variables. The 2-way multivariate analysis of covariance (MANCOVA) results showed higher QSM values in the left red nucleus (P=0.024) in PD patients compared with those in HCs, and in the bilateral globi pallidi [left/right (L/R): P=0.009/0.003], substantia nigra pars compacta (SNc; L/R: P=0.001/0.037), and right substantia nigra pars reticulata (SNr; P=0.002) in non-smokers compared with smokers, with no marked interaction effect between PD and smoking status observed when applying the Bonferroni adjustment for multiple comparisons. Using cigarette smoking status and the SI as separate moderator variables, the moderation was shown up by a significant interaction effect in a disordinal and double-edged form. In our results, smoking-moderated protection for PD movement deficits emerged when PD was progressed. Among the affected deep brain nuclei, the nuclei most moderated by the impact of cigarette smoking on the interaction between brain iron and PD symptoms were the thalamus [smoking status associated with the Unified Parkinson's Disease Rating Scale (UPDRS) total score, P=0.04 (L); rigidity, P=0.03 (L); SI associated with UPDRS-III, P (L/R) =0.049/0.0497; rigidity, P (L/R) =0.01/0.02; bradykinesia, P (L/R) =0.048/0.04], the right red nucleus (SI associated with rigidity, P=0.04; bradykinesia, P=0.02), and the left SNc [smoking status associated with the Hoehn and Yahr (H&Y) stage, P=0.01]. This was the first study investigating the impacts of current cigarette smoking on PD using quantified iron deposition. Our study confirmed the protective role of cigarette smoking against PD, consistent with the findings of previous studies. Furthermore, neuroprotection was present only when the PD pathology had progressed to a certain extent. In the interaction between iron deposition and clinical PD symptoms, our findings suggest that the thalamus, red nucleus, and SNc are likely to be the most affected nuclei moderated by cigarette smoking.

The enhanced T2 star weighted angiography (ESWAN) value for differentiating borderline from malignant epithelial ovarian tumors

PurposeTo investigate the potential of ESWAN in differentiating borderline epithelial ovarian tumors (BEOTs) from malignant epithelial ovarian tumors (MEOTs). MethodThirty-four patients with 37 lesions were enrolled, including 14 BEOTs and 23 MEOTs. The magnitude, phase, R2* and T2* maps were analyzed by two observers. The regions of interest were drawn along the boundaries of tumors on the slice with maximal solid area, according to fat suppression T2WI and T1WI. The consistency among the three measurements taken by two observers was tested by intra-class correlation coefficients. Agreement of average values measured by two observers was evaluated by Bland-Altman plots. All the data of BEOTs and MEOTs were compared using the independent-sample t test. The receiver operating characteristic curve was used to evaluate the diagnostic performance. ResultsNo statistical differences were observed in the magnitude and phase values between two tumor groups. The R2* value of BEOTs was lower than that of MEOTs (P < 0.001), whereas the T2* value of BEOTs was higher than that of MEOTs (P = 0.01). The area under the curve of R2* values was 0.894 and the corresponding cutoff value was 7.50 Hz, with the sensitivity, specificity and accuracy of 85.7%, 82.6% and 86.5%, respectively. The AUC of T2* values was 0.776 and the corresponding cutoff value was 143.73 ms with the sensitivity, specificity and accuracy of 71.4%, 82.6% and 78.4%, respectively. ConclusionsR2* and T2* values can be used for quantificationally differentiating BEOTs from MEOTs and the R2* has better diagnostic performance.

The early diagnosis of Parkinson's disease through combined biomarkers.

This study primarily aims to explore the value of combining the measurement of plasma α-synuclein oligomer levels with enhanced T2 star-weighted angiography (ESWAN) in the early diagnosis of Parkinson's disease. Sixty patients with early Parkinson's disease and 30 normal adults, with similar ages and genders, were enrolled in the study. Their levels of plasma α-synuclein oligomers were measured, and ESWAN was performed. The amplitudes, phases and R2* values of the head, body and tail of the ipsilateral and contralateral substantia nigra pars compacta (SNc) were measured, at the side of the limb with severe symptoms or early symptoms. The receiver operating characteristic (ROC) curve was used to explore the value of these indexes in the early diagnosis of Parkinson's disease. The plasma level of α-synuclein oligomer was significantly higher in the experimental group than in the control group (P<0.05). The amplitude values of the head and tail of contralateral SNcs were significantly lower in the experimental group than in the control group (P<0.05). In the single-index assessment, the serum α-synuclein oligomer had the highest specificity (70%), while the sensitivity of the amplitude of the head and tail of the contralateral SNc was 75% and 80%, respectively. The area under the curve, for the combination of these three indicators, was 0.827, diagnostic efficiency was particularly high, and sensitivity and specificity both reached 80%. The combined detection of plasma α-synuclein oligomer and amplitude of the head and tail of the SNc has high diagnostic specificity and sensitivity.

The value of ESWAN in diagnosis and differential diagnosis of prostate cancer: Preliminary study

ObjectiveTo evaluate the value of enhanced T2 star-weighted angiography (ESWAN) in diagnosis and differential diagnosis of prostate cancer by comparing the multiple indices of ESWAN in benign prostatic hyperplasia (BPH), prostate cancer (PCa) and the normal peripheral zone (PZ). MethodsTraditional MRI and ESWAN were performed on forty-nine clinically-diagnosed PCa patients, sixty BPH patients, and forty-six normal adult males. The ESWAN indices (magnitude value, phase value, R2* value and T2* value) measured on different regions of interest (ROIs) were analyzed. Additionally, receiver operating characteristic (ROC) analysis was performed to obtain the area under the curve (AUC), sensitivity, specificity, and optimal cut-off points of PCa and BPH, PCa and PZ respectively. ResultsThe magnitude value, phase value, R2* value and T2* value of PZ were 1529.43±254.43, 0.0689±0.1619, 16.57±8.11, 82.75±53.87, respectively; the magnitude value, phase value, R2* value, and T2* value of PCa were 1540.18±338.62, −0.0176±0.0919, 26.93±11.31, and 45.99±17.43, respectively; the magnitude value, phase value, R2* value, and T2* value of BPH were 1579.49±285.28, 0.0209±0.0839, 20.69±3.95, and 51.56±8.90, respectively. Compared with normal PZ, phase value of PCa was lower (t=−3.302, P=0.001), R2* value higher (t=5.326, P=0.000), and T2* value lower (t=−4.570, P=0.000); compared with BPH, phase value of PCa was lower (t=−2.261, P=0.026), R2* value higher (t=3.988, P=0.000), and T2* value lower (t=−2.155, P=0.033). When PCa and PZ were distinguished, the AUC of magnitude value, phase value, R2* value, and T2* value were respectively 0.539 (P=0.510), 0.679 (P=0.0007), 0.811 (P<0.0001), and 0.762 (P<0.0001); the diagnosis efficiency of R2* value was higher than that of T2* value (P=0.037), while the diagnosis efficiency of T2* value was equivalent to phase value (P=0.256). When PCa was differentiated from BPH, the AUC of magnitude value, phase value, R2* value, and T2* value were 0.518 (P=0.752), 0.612 (P=0.039), 0.705 (P=0.0001), and 0.685 (P=0.0006), respectively; there was no statistical difference in the diagnostic efficiency of phase value, R2* value, and T2* value. ConclusionsThe phase value, R2* value and T2* value can distinguish PCa and normal PZ, PCa and BPH, so they are valuable for the diagnosis and differential diagnosis of PCa, moreover, the diagnostic efficiency of R2* value is better than other indices.

Value of R2(*) in evaluating the biological behavior of primary hepatocellular carcinoma

To investigate the correlation between R2(*) value of enhanced T2 star-weighted angiography (ESWAN) sequence and primary hepatocellular carcinoma infiltration and tumor thrombus, and investigate the biological behavior of HCC. A total of 221 cases of patients' imaging data with MRI examination(including ESWAN sequence) diagnosed as primary HCC were retrospectively analyzed.All the patients were collected from January 2014 to September 2015 in the First Affiliated Hospital of Dalian Medical University.The differences of R2(*) values in different MR types of HCC were analyzed.All patients were divided into infiltration group and non-infiltration group, tumor thrombus group and non-tumor thrombus group, the R2(*) values of the paired groups were compared.The diagnostic efficiency of R2(*) in HCC infiltration and tumor thrombus were evaluated by ROC curve, and to find out the threshold values. The MR types of 221 patients included 90 cases of nodular type, 62 cases of massive type, 69 cases of diffuse type.70 patients had tumor thrombus.The R2(*) values of different MR types were (21.82±8.52), (24.17±8.84)and (34.45±11.73) Hz, respectively.There was no statistically significant difference between the nodular and the massive types (P=0.144), while the difference between the nodular and diffuse type, the massive and diffuse types were statistically significant(P=0.000). The R2(*) values of infiltration group and non-infiltration group were (34.45±11.73) and (22.78±8.70) Hz , the R2(*) values of tumor thrombus group and non-tumor thrombus group were (31.20±12.17) and (24.21±9.90) Hz, the difference also had statistically significant(t=7.397 and 4.534, P=0.000 and 0.000). The AUC of R2(*) values for infiltration and tumor thrombus were 0.804, 0.681. R2(*) ≥24.68 Hz was the threshold value to diagnose the infiltration and tumor thrombus. R2(*) value can be used as a MR non-enhancement quantitative index to evaluate the biological behavior of HCC.

Quantitative assessment of iron deposition in Parkinson's disease using enhanced T2 star-weighted angiography.

It has been reported that R2* is a sensitive marker for iron deposition. The aim of this study was to quantitatively assess iron deposition in Parkinson's disease (PD) using changes of R2* in enhanced T2 star-weighted angiography (ESWAN) and to discuss the value of ESWAN for PD. Fifty-four primary PD patients and twenty-eight healthy individuals were examined by ESWAN in the 3·0 T magnetic resonance imaging system. The R2* values were measured from the deep gray nuclei (including the substantia nigra [SN], red nuclei, globus pallidus, putamina, caudate nuclei, and thalami). The unified PD rating scale (UPDRS) III assessment, the nonmotor symptoms scale (NMSS), and the mini mental state examination (MMSE) were used to rate all the patients. The comparison of the R* values between the deep gray nuclei on the same side of the PD patients and the control group revealed significant differences in the SN and red nuclei (P < 0.05). There was a significant difference between Hoehn and Yahr (HY) 1 and HY2-4 patients in terms of the values of the SN. There was a slight correlation between the R* values of the SN of the PD patients (HY >1) and the UPDRS III ratings. No correlation between the R* signal values in the PD patients and the NMSS and MMSE scales was found. Iron concentrations in the regions of interest may represent the severity of the PD motor symptoms, and whether they are related to the nonmotor symptoms remains a question for further investigation. ESWAN offers special advantages in determining iron depositions in the brain and in enabling a sensitive diagnosis of PD, although further study is necessary.

Use of enhanced T2 star-weighted angiography (ESWAN) and R2* values to distinguish ovarian cysts due to endometriosis from other causes.

To evaluate the feasibility of enhanced T2 star-weighted angiography (ESWAN) in differentiating endometrial from non-endometrial cysts. Forty-nine patients with 60 histopathologically proven ovarian cystic lesions underwent pelvic MRI including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), liver acquisition with volume acceleration, and ESWAN. Ovarian cystic lesions were divided into endometrial cysts (group 1; n = 28), pyosalpinx and hydrosalpinx (group 2; n = 13), and ovarian cystic and cystic-solid tumors (group 3; n = 19). R2* (effective transverse relaxation rate) values were measured and pairwise comparison of the R2* values among the three groups was made using Kruskal-Wallis test. Receiver operating characteristic curves were used to calculate cutoff values and performance of R2* values for distinguishing among groups. T1WI signal intensity and R2* value were also compared using area under curve values. R2* values for group 1 were statistically higher than groups 2 and 3 (15.37, 1.40, and 1.79 Hz, respectively; P < 0.001). The cutoff value for R2* was 7.43 Hz with a sensitivity, specificity, PPV, NPV, and accuracy of 96.43, 87.50, 87.10, 96.55, and 91.67%, respectively. There was no significant difference between the R2* value and T1WI in diagnosing endometrial cysts. The R2* value provides an effective way to discriminate endometrial cysts from other ovarian cystic lesions.

Assessment of Iron Deposition and White Matter Maturation in Infant Brains by Using Enhanced T2 Star Weighted Angiography (ESWAN): R2* versus Phase Values

Background and PurposeIron deposition and white matter (WM) maturation are very important for brain development in infants. It has been reported that the R2* and phase values originating from the gradient-echo sequence could both reflect the iron and myelination. The aim of this study was to investigate age-related changes of R2* and phase value, and compare their performances for monitoring iron deposition and WM maturation in infant brains.Methods56 infants were examined by enhanced T2 star weighted angiography (ESWAN) and diffusion tensor imaging in the 1.5T MRI system. The R2* and phase values were measured from the deep gray nuclei and WM. Fractional anisotropy (FA) values were measured only in the WM regions. Correlation analyses were performed to explore the relation among the two parameters (R2* and phase values) and postmenstrual age (PMA), previously published iron concentrations as well as FA values.ResultsWe found significantly positive correlations between the R2* values and PMA in both of the gray nuclei and WM. Moreover, R2* values had a positive correlation with the iron reference concentrations in the deep gray nuclei and the FA in the WM. However, phase values only had the positive correlation with PMA and FA in the internal capsule, and no significant correlation with PMA and iron content in the deep gray nuclei.ConclusionsCompared with the phase values, R2* may be a preferable method to estimate the iron deposition and WM maturation in infant brains.

Quantitative assessment of iron deposition in the midbrain using 3D-enhanced T2 star weighted angiography (ESWAN): A preliminary cross-sectional study of 20 Parkinson’s disease patients

Conventional magnetic resonance imaging (MRI) assesses neurodegenerative structural changes in the cerebral anatomy of Parkinson's disease (PD) patients but cannot detect non-structural abnormalities; however, enhanced T2 star weighted angiography (ESWAN) can precisely indicate PD-related substantia nigra (SN) iron deposition. The differences in ESWAN-based parameters between different PD stages were assessed using midbrain iron deposits of 20 PD patients aged 64.3±12.7 (41–85) years grouped by Hoehn and Yahr staging into minimal (stages ≤2.5) or moderate to severe (stages ≥3.0) motor impairment groups and 14 healthy control subjects. Conventional MRI and ESWAN measurements of mean phase value (MPV) and midbrain dimensions (width and diameter) revealed similar anatomical characteristics; however, ESWAN revealed the presence of smaller MPVs and SN pars compacta (SNc) (P<0.01) and a negative correlation between reduction extent and motor impairment (P<0.01). SNc width to midbrain diameter was reduced in moderate to severe impairment patients versus control and minimal impairment patients (both P<0.01). A positive correlation was found between MPV and width or SNc width to midbrain diameter ratio (P<0.01 and P<0.05, respectively). Minimal impairment group mean MPV and substantia nigra pars reticulata (SNr) width evidenced no significant reduction, unlike significant reductions in the moderate to severe impairment group (P<0.01). No significant changes were observed in MPV or width in the RN region (P>0.05). ESWAN allows for early and accurate iron deposition determination in PD patients, particularly useful as a supplement to conventional MRI in early-stage PD patients.

Assessment of brain maturation in the preterm infants using diffusion tensor imaging (DTI) and enhanced T2 star weighted angiography (ESWAN)

PurposeTo assess the brain maturation of preterm infants using diffusion tensor imaging (DTI) and enhanced T2 star weighted angiography (ESWAN). Materials and methodsConventional magnetic resonance imaging (MRI), DTI and ESWAN were performed in 60 preterm infants and 21 term controls. 60 preterm infants were subgrouped to two groups according to the age at imaging: before and at term-equivalent age (TEA). Fractional anisotropy (FA), apparent diffusion coefficient (ADC) map from DTI, T2* and R2* maps from ESWAN were post-processed at an off-line workstation. The values of FA, ADC, T2* and R2* from the posterior limb of internal capsule (PLIC), frontal white matter (FWM), occipital white matter (OWM) and lentiform nuclei (LN) were determined. These parameters were compared between preterm and term infants. Correlations of DTI and ESWAN parameters with the gestational age, postmenstrual age and postnatal age were analyzed. ResultsADCs of FWM, OWM and LN, and T2* values of the PLIC and LN were higher in the preterm infants at TEA compared with the term controls.The correlations were existed between the postmenstrual age and the values of FA, ADC, T2*, R2* from the PLIC, values of ADC, T2*, R2* from the LN, T2* value from the OWM. The correlations were also found between the postnatal age and the values of FA, ADC, T2* from the PLIC, and T2* value from the LN. ConclusionThe maturity of preterm brain around TEA was different from that of term controls and appeared to be independent of the prematurity at birth. T2* was one of valuable indices to evaluate brain maturation in preterm infants.

Analysis of iron deposition in the brain lesions of patients with multiple sclerosis by three dimensional enhanced T2-star weighted angiography

Objective To explore the values of 3D enhanced T2-star weighted angiography (ESWAN) in detecting iron deposition of the brain in patients with multiple sclerosis ( MS).Methods Conventional MRI and 3D ESWAN were performed in 22 patients with released-remitting MS(RR-MS) and in 22 age- and gender-matched normal controls.Both the magnitude images and phase images were available after post processing of the original ESWAN data post processing.The expanded disability status scale (EDSS) scores of the patients were from 0 to 8.5,and the course of disease were between 0.5 year and 15 years.The manifestation of MS lesions was evaluated on conventional MR images and ESWAN images by two experienced radiologists with blind methods.The phase values were measured for MS lesions between the semioval center and periventricular white matter and the corresponding regions in the normal control group were measured as well The Wilcoxon rank test was used to compare the differences of phase values between MS patients and normal controls,and the Spearman rank correlation analysis were used to analyze the correlations among the phase values of MS lesions,EDSS scores and course of disease of MS patients.Results ( 1 ) MS lesions were observed on magnitude images and phase images,respectively and together.Two hundred and thirteen(32.8％ )lesions were detected on both the magnitude images and phase images,164 (25.2％)lesions were detected on the magnitude images only,and 273 (42.0％) lesions were detected on the phase images only.A total of 650 lesions were observed on the ESWAN,which showed more 42 lesions than conventional images(608).Among 486(273 + 213 )lesions observed on the phase images,205 (31.5％) lesions were homogeneously hypointense,45 (6.9％ ) lesions showed hypointense ring,and 236 (36.4％ ) lesions were inhomogeneously hypointense.(2) “ Penetrating veins” were showed in 424 (65.2％ ) periventricular lesions.The “penetrating veins” showed dilated and prolonged in 198 (30.5％ ) acute lesions,thin and short in 208 (32.9％ ) chronic lesions.However,the “penetrating veins” of 12 ( 1.8％ ) chronic lesions in 5 stable MS patients were expanded and prolonged slightly.( 3 ) The average phase value of the lesions ( - 0.05 ± 0.08) in patients with RR-MS was significantly lower than that of corresponding to regions (0.06 ± 0.05 ) in the normal control group( Z = 22.30,P ＜ 0.01 ).(4) The phase values of MS lesions were significantly correlated to the EDSS and course of disease of patients with RR-MS (r = -0.98,0.99 respectively,P ＜ 0.01 ).Conclusion ESWAN can be helpful in the evaluation and quantification of abnormal iron deposition in MS lesions,which provides important values for the pathogenesis and pathological study for MS patients. Key words: Multiple sclerosis; Magnetic resonance imaging; Iron