T2WI Signal Intensity Research Articles

Risk factors affecting long-term efficacy of ultrasound-guided high-intensity focused ultrasound treatment for multiple uterine fibroids

Objectives To investigate the long-term efficacy of ultrasound-guided high-intensity focused ultrasound (USgHIFU) for multiple uterine fibroids and the factors associated with recurrence. Materials and methods Five hundred and forty-nine patients with multiple uterine fibroids treated with USgHIFU from June 2017 to June 2019 were retrospectively analyzed. The Pictorial Blood Loss Assessment Chart (PBAC) was used to assess menstrual blood loss. The patients were asked to undergo pre- and post-USgHIFU magnetic resonance imaging (MRI) and complete routine follow-up after USgHIFU. Cox regression analysis was used to investigate the risk factors associated with recurrence. Results The median number of fibroids per patient was 3 (interquartile range: 3–4), and a total of 1371 fibroids were treated. Among them, 446 patients completed 3 years follow-up. Recurrence, defined as PBAC score above or equal to 100 and/or the residual fibroid volume increased by 10%, was detected in 90 patients within 3 years after USgHIFU, with a cumulative recurrence rate of 20.2% (90/446). The multi-factor Cox analysis showed that age was a protective factor for recurrence. Younger patients have a greater chance of recurrence than older patients. Mixed hyperintensity of fibroids on T2WI and treatment intensity were risk factors for recurrence. Patients with hyperintense uterine fibroids and treated with lower treatment intensity were more likely to experience recurrence than other patients after USgHIFU. No major adverse effects occurred. Conclusions USgHIFU can be used to treat multiple uterine fibroids safely and effectively. The age, T2WI signal intensity and treatment intensity are factors related to recurrence.

A Novel DNA Aptamer Probe Recognizing Castration Resistant Prostate Cancer in vitro and in vivo Based on Cell-SELEX.

Early recognition of castration-resistant state is of significance for timely adjustment of treatment regimens and improvement of prognosis. This study aims to screen new aptamers CRda8 and CRda21 which recognize castration resistant prostate cancer (CRPC) cells with high affinity and specificity by SELEX technology. The enrichment of specific aptamer candidates was monitored by flow cytometric analysis. The affinity and specificity of aptamer candidates were evaluated by flow cytometry and immunofluorescence assay. MR imaging of CRda21-conjugated polyethylene glycol (PEG)-Fe3O4 nanoparticles to CRPC was further explored in vivo. Both aptamers showed high specificity to target cells with dissociation constants in the nanomolar range, and did not recognize other tested cells. The staining of clinical tissue sections with fluorescent dye labeled aptamers showed that sections from CRPC exhibited stronger fluorescence while sections from benign prostatic hyperplasia and androgen dependent prostate cancer did not exhibit notable fluorescence. In vivo MRI demonstrated that CRda21-conjugated PEG-Fe3O4 had good affinity to CRPC and produced strong T2WI signal intensity reduction distinguished from peritumoral tissue. The high affinity and specificity of CRda8 and CRda21 make the aptamer hold potential for early recognition of castration-resistant state and diagnosis of CRPC at the cellular level.

10053-MNG-1 STRATIFICATION OF TUMOR VOLUME GROWTH RATE USING RISK FACTORS IN SUPRATENTORIAL MENINGIOMAS

Abstract BACKGROUND The natural history of meningiomas is still unclear, and no guidelines have been established based on objective indices regarding the necessity and timing of therapeutic intervention. Objective: We attempted to provide statistics on the characteristics of tumor volume change, stratify tumor growth by risk factors, and generate a predictive tumor volume curve based on the statistics, with the aim of describing the natural history of meningiomas. METHODS 313 cases were included in the study, with the origin of meningioma being the circumflex and parasagittal sinus areas and the cerebral sickle region, and with multiple MRI scans performed at intervals of at least 3 months. Relative growth rate (RGR) and annual volume change (AVC) were calculated by tumor volume, and the patients were classified into three groups according to the combination of gender, age, and MRI T2WI signal intensity, and compared. RESULTS The median RGR and AVC of the entire cohort were 6.1% and 0.20 cm3/year, respectively, and there were significant differences between groups in gender (p=0.018) and MRI T2WI (p < 0.001) for RGR and tumor location (p=0.025) and initial tumor volume (p < 0.001)for AVC. The median RGR and AVC in the classification were 17.5% and 1.05 cm3/year for the very high growth group, 8.2% and 0.33 cm3/year for the high growth group, and 3.4% and 0.04 cm3/year for the low growth group, showing significant differences between the groups (p < 0.001). The predicted tumor volume curve showed an average 2.24-fold or 5.24 cm3 increase in volume over 5 years in the very high-growth group, while little tumor volume change was observed in the low-growth group. CONCLUSION The combination of growth risk factors allowed stratification of tumor growth and provided a predictive tumor volume curve for each county. The results may assist in the treatment of supratentorial meningiomas.

Intravoxel incoherent motion diffusion-weighted MRI for predicting the efficacy of high-intensity focused ultrasound ablation for uterine fibroids.

To evaluate the significance of magnetic resonance (MR) intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) quantitative parameters in predicting early efficacy of high-intensity focused ultrasound (HIFU) ablation of uterine fibroids before treatment. 64 patients with 89 uterine fibroids undergoing HIFU ablation (51 sufficient ablations and 38 insufficient ablations) were enrolled in the study and completed MR imaging and IVIM-DWI before treatment. The IVIM-DWI parameters, including D (diffusion coefficient), D* (pseudo-diffusion coefficient), f (perfusion fraction) and relative blood flow (rBF) were calculated. The logistic regression (LR) model was constructed to analyze the predictors of efficacy. The receiver operating characteristic (ROC) curve was drawn to assess the model's performance. A nomograph was constructed to visualize the model. The D value of the sufficient ablation group (931.0(851.5-987.4) × 10-6 mm2/s) was significantly lower than that of the insufficient ablation group (1052.7(1019.6-1158.7) × 10-6 mm2/s) (p<0.001). However, differences in D*, f, and rBF values between the groups were not significant (p>0.05). The LR model was constructed with D value, fibroid position, ventral skin distance, T2WI signal intensity, and contrast enhanced degree. The area under the ROC curve, specificity, and sensitivity of the model were 0.858 (95% confidence interval: 0.781, 0.935), 0.686, and 0.947. The nomogram and calibration curves confirmed that the model had excellent performance. The IVIM-DWI quantitative parameters can be used to predict early effects of HIFU ablation on uterine fibroids. A high D value before treatment may indicate that the treatment will be less effective in the early stages.

Multiparametric Magnetic Resonance Imaging With Comprehensive Assessment of Prostate Volume, Morphology, and Composition Better Reflects the Correlation With International Prostate Symptom Score

To investigate the application of multiparametric MRI (mp-MRI) for comprehensive evaluation of the correlation between the characteristics of the transitional zone and the International Prostate Symptom Score (IPSS) in patients with benign prostatic hyperplasia (BPH). We retrospectively recruited 210 patients with biopsy-proven BPH who underwent preoperative mp-MRI and were assigned an IPSS. The evaluation indicators included prostate volumetric parameters [total prostate volume (TPV), transition zone volume (TZV), and transition zone index (TZI, TZI=TZV/TPV)], prostate morphological parameters [intravesical prostatic protrusion (IPP), and presumed circle area ratio (PCAR)] and prostate compositional parameters [apparent diffusion coefficient (ADC), and mean signal intensity of T2WI (mean-SI-T2WI)]. The Pearson (r) correlation coefficient, one-way analysis of variance (ANOVA) and multiple linear regression analysis were used to build a regression model for evaluating the correlation between MRI-derived parameters and IPSS, IPSS-storage symptom (IPSS-ss), IPSS-voiding symptom (IPSS-vs). Significant correlations were found between IPSS, IPSS-ss, IPSS-vs and prostate MRI-derived parameters, including TPV (r=0.350; r=0.466; r=0.225, P<0.001), TZV (r=0.374; r=0.492; r=0.243, P<0.001), TZI (r=0.383; r=0.313; r=0.354, P<0.001), PCAR (r=0.481; r=0.356; r=0.469, P<0.001), ADC(r=-0.198; r=-0.053; r=-0.239, P<0.05) and mean-SI-T2WI (r=-0.626; r=-0.310; r=-0.687, P<0.001) respectively. Based on multiple linear regression analysis, the impact of mean-SI-T2WI and TZI on total IPSS were statistically significant (P<0.05), and the regression equation established with the analysis [IPSS=39.224+8.469×TZI+(-0.09)×(mean-SI-T2WI)] was statistically significant (F=104.995, P<0.001). Mp-MRI could be used to evaluate the volume and morphology of BPH. In particular, mean-SI-T2WI and ADC could be used to describe the internal composition of the prostate. The imaging parameters were effective for evaluating BPH.

MNG-3 STRATIFICATION OF TUMOR GROWTH BY RISK FACTORS AND PREDICTED TUMOR VOLUME CURVES FOR SUPRATENTORIAL MENINGIOMAS

Abstract Background The natural history of meningiomas is still unclear, and no guidelines have been established based on objective indices regarding the necessity and timing of therapeutic intervention.Objective: We attempted to provide statistics on the characteristics of tumor volume change, stratify tumor growth by risk factors, and generate a predictive tumor volume curve based on the statistics, with the aim of describing the natural history of meningiomas. Methods 313 cases were included in the study, with the origin of meningioma being the circumflex and parasagittal sinus areas and the cerebral sickle region, and with multiple MRI scans performed at intervals of at least 3 months. Relative growth rate (RGR) and annual volume change (AVC) were calculated by measuring tumor volume, and the patients were classified into three groups according to the combination of gender, age, and MRI T2WI signal intensity, and compared. Results The median RGR and AVC of the entire cohort were 6.1% and 0.20 cm3/year, respectively, and there were significant differences between groups in gender (p=0.018) and MRI T2WI (p &amp;lt; 0.001) for RGR and tumor location (p=0.025) and initial tumor volume (p &amp;lt; 0.001)for AVC. The median RGR and AVC in the classification were 17.5% and 1.05 cm3/year for the very high growth group, 8.2% and 0.33 cm3/year for the high growth group, and 3.4% and 0.04 cm3/year for the low growth group, showing significant differences between the groups (p &amp;lt; 0.001). The predicted tumor volume curve showed an average 2.24-fold or 5.24 cm3 increase in volume over 5 years in the very high-growth group, while little tumor volume change was observed in the low-growth group. Conclusion The combination of growth risk factors allowed stratification of tumor growth and provided a predictive tumor volume curve for each county. The results may assist in the treatment of meningiomas.

Differentiation between atypical sinonasal non-Hodgkin's lymphoma and inverted papilloma

To seek additional magnetic resonance imaging (MRI) features to improve the accuracy of differentiation between atypical sinonasal non-Hodgkin's lymphoma (NHL) and inverted papilloma (IP) using conventional MRI and apparent diffusion coefficient (ADC) maps. MRI examinations from 44 atypical cases (21 NHLs and 23 IPs) in sinonasal regions were reviewed retrospectively. Imaging features included tumour laterality, extension, T1-weighted imaging (WI)/T2WI signal intensity homogeneity and ratios, enhancement homogeneity and ratios, and ADCmean. In cases of NHL, homogeneous signal intensity was often observed on T2WI, which was homogeneous and significantly less enhanced than the turbinate, with lower ADCmean. Whereas in IPs, heterogeneous signal intensity was seen on T2WI, which was heterogeneous and of comparable enhancement to the turbinate, and higher ADCmean values were commonly seen. An ADCmean cut-off point of 1.10×10-3 mm2/s achieved 100% sensitivity, 90% specificity, and 90% accuracy. In addition, special features were observed that support the distinction between the two tumours, including intestinal pattern enhancement in NHL and spot-like appearance on T2WI and enhancement in IP. ADCmean was the most valuable metric for differentiating between the atypical sinonasal NHLs and IPs.

Value of non-Gaussian diffusion imaging with a fractional order calculus model combined with conventional MRI for differentiating histological types of cervical cancer

ObjectiveThis study aimed to evaluate the value of a fractional order calculus (FROC) model combined with conventional magnetic resonance imaging (MRI) for differentiating cervical adenocarcinoma (CAC) from squamous cell carcinoma (SCC). MethodsDiffusion-weighted imaging (DWI) with 9 b values (0–2000s/mm2) was carried out in 57 cervical cancer patients. Diffusion coefficient (D), fractional order parameter (β), and microstructural quantity (μ) together with apparent diffusion coefficient (ADC) were calculated and compared between the CAC and SCC groups. Conventional MRI features included T2WI signal intensity (SI), unenhanced-T1WI SI, enhanced-T1WI SI, and ∆T1WI SI, which were also compared between the two groups. Receiver operating characteristic (ROC) analysis was employed to assess the performance of FROC parameters, ADC, and conventional MRI features in differentiating CAC from SCC. Resultsβ was significantly lower in the CAC group than in the SCC group (0.682 ± 0.054 vs. 0.723 ± 0.084, P = 0.035), while D and μ were not significantly different between the two groups (D, P = 0.171; μ, P = 0.127). There was no significant difference in the ADC value between the two groups (P = 0.053). In conventional MRI features, enhanced-T1WI SI was significantly higher in the SCC group than in the CAC group (985.78 ± 130.83 vs. 853.92 ± 149.65, P = 0.002). The area under the curve (AUC) of β, ADC, and enhanced-T1WI SI was 0.700, 0.683, and 0.799, respectively. The combination of β, ADC, and enhanced-T1WI SI revealed optimal diagnostic performance in differentiating CAC from SCC (AUC = 0.930), followed by β + enhanced-T1WI SI (AUC = 0.869), ADC+ enhanced-T1WI SI (AUC = 0.817), and β + ADC (AUC = 0.761). ConclusionThe FROC model can serve as a noninvasive and quantitative imaging technique for differentiating CAC from SCC. β combined with ADC and enhanced-T1WI SI had the highest diagnostic efficiency.

Amide Proton Transfer Weighted MR Imaging for Predicting Meningioma Stiffness: A Feasibility Study.

Stiffness of meningioma is an important factor affecting the surgical resection and the prognosis of patients. To examine the feasibility of APTw-magnetic resonance imaging (MRI) in evaluating meningioma stiffness. Retrospective. Seventy-one patient with meningiomas, 39 were male and 32 were female; the mean age was 51 ± 10 years. 3.0T; Turbo-spin-echo T1 -weighted and Gd-T1 -weighted sequence; Turbo-spin-echo T2 -weighted sequence; 2D fat-suppressed, turbo-spin-echo APTw pulse sequence. The T1 WI signal intensity score, T2 WI signal intensity score, APTwmin , APTwmax , and APTwmean values were compared between soft, medium stiff and stiff meningiomas or non-stiff meningiomas and stiff meningiomas group. Chi-square test, one-way ANOVA analysis, independent-samples t-test, intra-class correlation coefficient, rank-sum test, receiver operating characteristic curve analysis. P < 0.05 was considered statistically significant in all tests. APTwmin and APTwmean in the stiff group were significantly lower than that in the non-stiff group (2.79% ± 0.42% vs. 1.90% ± 0.60% and 3.20% ± 0.31% vs. 2.55% ± 0.61%). APTwmin and APTwmean in the stiff group were significantly lower than that in the medium stiff and soft groups (1.90% ± 0.60% vs. 2.69% ± 0.40% and 3.12% ± 0.32%, 2.55% ± 0.61% vs. 3.17% ± 0.33% and 3.39% ± 0.18%), APTwmin in the medium stiff group was significantly lower than in the soft group, there was no significant difference in APTwmean between the medium stiff and soft groups (P=0.190). APTwmin showed the best diagnostic performance for evaluating meningioma stiffness with an area under the curve of 0.913, when the APTwmin was lower than 2.4%, the meningioma was defined as a stiff tumor, the sensitivity, specificity, and accuracy were 87.1%, 87.5%, and 85.9%, respectively. APTw-MRI could be used to evaluate meningioma stiffness, with APTwmin having the best evaluative efficiency. 3 TECHNICAL EFFICACY: Stage 1.

MR-Guided Microwave Ablation for Lung Malignant Tumor: A Single Center Prospective Study.

ObjectivesTo prospectively investigate the feasibility and efficacy of MRI-guided MWA for lung malignant tumor in our single center.Materials and Methods22 patients [mean age, 56.86 ± 13.05(23–73)years] with 23 malignant lung tumors were enrolled in the study. 21 patients had a single lesion and 1 patient had 2 lesions in the ipsilateral lung. The average maximum diameter of the lesion was 1.26 ± 0.65 (0.50-2.58)cm. Percutaneous MWA was guided by 1.5T MRI scanner using a MR-compatible microwave antenna to the target the lung lesions and ablation area was monitored intraoperatively by using a shielded MR-compatible microwave device and then follow-up.ResultsAll patients were successfully treated under MR-guided MWA for lung tumors. Average operation time was 72.21 ± 24.99 (36–158) mins. T2WI signal intensity of the lesion gradually decreased over the course of MWA. The center of the ablated zones showed a short T1 and short T2 signals with the ring-like of long T1 and long T2 signals surrounded after immediately evaluation. No serious complications occurred. The average follow-up period was 12.89 ± 4.33 (2.0-19.6) months. Local recurrence occurred in one patient, representing a technical efficacy of 95.5% (21/22).ConclusionMagnetic resonance-guided microwave ablation for lung malignant tumor was feasible and demonstrated unique advantages in efficacy evaluation.

Diagnostic Value of MRI Combined with CXCR4 Expression Level in Lymph Node Metastasis Head and Neck Squamous Cell Carcinoma.

Objective To explore the diagnostic value of magnetic resonance imaging (MRI) combined with CXCR4 expression levels in lymph node metastasis of the head and neck squamous cell carcinoma (HNSCC). Methods 289 patients with HNSCC were divided into lymph node metastasis group (LNM group, n = 171) and non-LNM group (n = 118) according to the pathological examination results. MRI was used to scan the patient's lesions and cervical lymph nodes, and ADC was measured by MRI diffusion weighting imaging. The expression of CXCR4 in tumor tissues was detected by qRT-PCR. Logistic regression was used to analyze the risk factors of HNSCC lymph node metastasis. ROC curve was used to analyze the diagnostic effects of MRI, CXCR4, and MRI combined with CXCR4 on HNSCC lymph node metastasis. Results Compared with the non-LNM group, patients in the LNM group had a lower degree of pathological differentiation, and the positive rate of TNM staging and vascular invasion was higher. The signal intensity of T1WI and T2WI were low intensity and high intensity, respectively, and the ADC value was significantly reduced. At the same time, the expression level of CXCR4 in the tumor tissues of the LNM group was also significantly increased. In addition, compared with MRI and CXCR4 used alone, MRI combined with CXCR4 has a higher predictive value. Conclusion MRI has a good effect in demonstrating lymph node metastasis. CXCR4 is significantly upregulated in lymph node metastasis tumor tissue. The combination of the two can be used for clinical diagnosis of HNSCC lymph node metastasis.

Transvaginal Aspiration for Management of Huge Ovarian Endometrioma in Pregnancy

Study Objective To demonstrate a minimally invasive approach of a huge ovarian cyst during pregnancy. Design A step-by-step explanation of the patient's condition, diagnosis, surgical technique, and post-operative results. Setting The patient underwent transvaginal procedure in the lithotomy position and under intravenous sedation and ventilation by face mask. Patients or Participants A 34-year-old woman, gravida 1 at 12 weeks 5 days’ gestation, presented with huge ovarian cyst. A transvaginal ultrasound demonstrated ovarian cyst measuring 10.4 × 8.2 cm with no evidence of malignancy, no free fluid, and a normal-appearing contralateral ovary. The crown-rump length measured 5.92 cm. On non-enhanced magnetic resonance imaging (MRI), 11 × 7 cm sized cystic lesion with high signal intensity in T1-weighted image (WI) and T1-weighted fat suppressed image, low signal intensity in T2 WI suggesting endometrioma, located in cul-de-sac was noted. Because the cyst was huge and deeply located in cul-de-sac, and the uterus was enlarged to 13 weeks size, approach through laparoscopy or even laparotomy was thought to be difficult and the risk of manipulation for uterus was high. So, we decided to aspirate the ovarian cyst through the vaginal route. Interventions Ultrasound-guided transvaginal aspiration was performed using an 18-G needle. Measurements and Main Results The operation time was 4 hours and 35 minutes with 305 mL dark brownish fluid drained. The patient recovered well and was discharged 2days after the procedure. There was no intraoperative or postoperative complication. Postoperative ultrasound revealed neither recurrence nor fetal abnormality. Until delivery, the patient was free of symptom and ultrasound revealed neither recurrence nor fetal abnormality. Conclusion In select pregnant woman with endometrioma requiringintervention, the risks of surgery may be minimized with aspiration. Transvaginal ultrasound-guided aspiration is a safe, feasible, and effective minimally invasive procedure for huge ovarian endometrioma in pregnancy. To demonstrate a minimally invasive approach of a huge ovarian cyst during pregnancy. A step-by-step explanation of the patient's condition, diagnosis, surgical technique, and post-operative results. The patient underwent transvaginal procedure in the lithotomy position and under intravenous sedation and ventilation by face mask. A 34-year-old woman, gravida 1 at 12 weeks 5 days’ gestation, presented with huge ovarian cyst. A transvaginal ultrasound demonstrated ovarian cyst measuring 10.4 × 8.2 cm with no evidence of malignancy, no free fluid, and a normal-appearing contralateral ovary. The crown-rump length measured 5.92 cm. On non-enhanced magnetic resonance imaging (MRI), 11 × 7 cm sized cystic lesion with high signal intensity in T1-weighted image (WI) and T1-weighted fat suppressed image, low signal intensity in T2 WI suggesting endometrioma, located in cul-de-sac was noted. Because the cyst was huge and deeply located in cul-de-sac, and the uterus was enlarged to 13 weeks size, approach through laparoscopy or even laparotomy was thought to be difficult and the risk of manipulation for uterus was high. So, we decided to aspirate the ovarian cyst through the vaginal route. Ultrasound-guided transvaginal aspiration was performed using an 18-G needle. The operation time was 4 hours and 35 minutes with 305 mL dark brownish fluid drained. The patient recovered well and was discharged 2days after the procedure. There was no intraoperative or postoperative complication. Postoperative ultrasound revealed neither recurrence nor fetal abnormality. Until delivery, the patient was free of symptom and ultrasound revealed neither recurrence nor fetal abnormality. In select pregnant woman with endometrioma requiringintervention, the risks of surgery may be minimized with aspiration. Transvaginal ultrasound-guided aspiration is a safe, feasible, and effective minimally invasive procedure for huge ovarian endometrioma in pregnancy.

Selection of DNA Aptamers Recognizing EpCAM-Positive Prostate Cancer by Cell-SELEX for in vitro and in vivo MR Imaging

BackgroundThe sensitive and specific detection of pathogenic cells is important in tumor diagnosis at an early stage. Aptamers are short single-stranded oligonucleotides evolved from systematic evolution of ligands by exponential enrichment (SELEX). It has been proved that aptamers can interact with cognate target molecules with high affinity and specificity and have great potential in the development of medical imaging at molecular level.PurposeTo select epithelial cell adhesion molecule (EpCAM) specific aptamers targeting prostate cancer and further to conjugate aptamers with GoldMag nanoparticles (a typical iron oxide core/gold shell structure) to construct magnetic molecular probes for medical imaging.MethodsEpCAM-specific aptamers were selected by Cell-SELEX. The enrichment of specific aptamer candidates was monitored by flow cytometric analysis. Aptamers were further conjugated with GoldMag nanoparticles to construct magnetic molecular probes. The affinity and specificity of aptamer candidates and aptamer-conjugated GoldMag nanoparticles were evaluated. The MR imaging of aptamer-conjugated GoldMag nanoparticles to prostate cancer was further explored in vitro and in vivo.ResultsAfter 12 rounds of selection, aptamer candidates Eppc6 and Eppc14 could specifically target three types of prostate cancer cells, revealing a high affinity of Eppc6 and Eppc14. Moreover, aptamer-conjugated GoldMag nanoparticles not only exhibited good affinity to different prostate cancer cells but also produced strong T2WI signal intensity reduction distinguished from peritumoral tissue in MRI, indicating that the molecular probes possess both the affinity properties of EpCAM-specific aptamer and the superparamagnetic features of iron oxide.ConclusionOur study indicates that aptamer Eppc6 and Eppc14 can recognize prostate cancer cells and tissues. The aptamer-conjugated GoldMag nanoparticles constructed in the study can be used as a molecular imaging agent for detection of PCa in MRI.

A Prediction of NPVR ≥ 80% of Ultrasound-Guided High-Intensity Focused Ultrasound Ablation for Uterine Fibroids.

Objective: To evaluate factors in predicting the treatment outcome of ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for uterine fibroids with a non-perfused volume ratio (NPVR) of at least 80%.Methods: One thousand patients with uterine fibroids who received USgHIFU were enrolled. Thirty-two independent variables of four dimensions of data set, including general information of patients, clinical symptoms, laboratory tests, and fibroid imaging characteristics, were used to investigate the potential predictors of the NPVR of at least 80% by multivariate logistic regression. NPVR was the gold standard for evaluating the efficiency of HIFU ablation, and a NPVR of at least 80% was considered sufficient ablation, while partial ablation was defined as having an NPVR of <80%.Results: Out of 1,000 fibroids, 758 obtained sufficient ablation and 242 obtained partial ablation, and the median NPVR was 88.3% (interquartile range: 80.3–94.8%). The probability of NPVR reaching 80% fibroids with a signal intensity of T2WI of hypointense, isointense, and hyperintense was 86.4, 76.5, and 62.6%, respectively; fibroids with an enhancement type of T1WI of slight, irregular, and regular was 81.5, 73.6, and 63.7%, respectively; and fibroids with uterine anteroposterior of 30–130 mm was 57.7–78.3%, respectively. In patients with a platelet count of 50 × 109/L−550 × 109/L, the probability of NPVR reaching 80% is from 53.4 to 80.1%, respectively.Conclusions: In predicting NPVR ≥ 80%, the signal intensity on T2WI was the most important factor affecting ablative efficiency, followed by enhancement type on T1WI, uterine anteroposterior, and platelet count.

The value of MRI plain scan and DWI in the diagnosis of brain metastases

Objective: To investigate the clinical value of magnetic resonance imaging (MRI) plain scan and diffusion weighted imaging (DWI) in the diagnosis of brain metastases. Methods: The MRI plain imaging findings of 105 cases with brain metastases and 103 cases without brain metastases confirmed by enhanced MRI examination and clinical diagnosis were retrospectively analyzed. The comparisons of plain MRI findings including T1 weighted image (T1WI), T2WI, T2/fluid attenuated inversion recovery (T2/FLAIR), DWI and apparent diffusion coefficient (ADC) values were made between brain metastases and non-brain metastases. Results: The numbers of hypo-intensity, iso-intensity, hyper-intensity and heterogeneous signal intensity of T1WI in the brain metastatic group were 54, 23, 9 and 19, respectively, while the numbers of hypo-intensity and iso-intensity in the non-brain metastatic group were 52 and 51, respectively, with statistically significant difference (P<0.001). The numbers of hypo-intensity, iso-intensity, hyper-intensity and heterogeneous signal intensity of T2WI in the brain metastatic group were 1, 9, 72 and 23, respectively, while the numbers of iso-intensity and hyper-intensity in the non-brain metastatic group were 11 and 92, respectively, with statistically significant difference (P<0.001). The numbers of hypo-intensity, hyper-intensity and heterogeneous signal intensity of DWI in the brain metastatic group were 4, 31 and 65, respectively, while the number of hyper-intensity in the non-brain metastatic group was 4 and others were iso-intensity, respectively, with statistically significant difference (P<0.001). The numbers of hypo-intensity, iso-intensity, hyper-intensity and heterogeneous signal intensity of T2WI/FLAIR in the brain metastatic group were 4, 5, 60 and 36, respectively, while all cases in the non-brain metastatic group were hyper-intensity, with statistically significant difference (P<0.001). The number of lesion accompanied with peripheral edema in the brain metastatic group were 69 cases, significantly higher than 0 cases in the non-brain metastatic group (P<0.001). The mean ADC value in the brain metastatic group were (0.919±0.019)×10(-3) mm(2)/s, significantly lower than (1.098±0.012)×10(-3) mm(2)/s of non-brain metastatic group (P<0.05). Conclusions: For patients with a history of primary malignancy, the MRI plain scan signals of T1WI, T2WI, T2WI/FLAIR and DWI are significantly different between brain metastatic tumor and non-metastatic tumor. The mixed signal, peripheral edema and the restriction of DWI diffusion indicate brain metastases. The combined application of the above parameters can improve the diagnostic efficacy of predicting brain metastases, and contrast enhancement MRI examination should be performed for the confirmation of diagnosis.

MRI features of the normal prostatic peripheral zone: the relationship between age and signal heterogeneity on T2WI, DWI, and DCE sequences

ObjectivesTo assess the multiparametric MRI (mpMRI) appearances of normal peripheral zone (PZ) across age groups in a biopsy-naïve population, where prostate cancer (PCa) was subsequently excluded, and propose a scoring system for background PZ changes.MethodsThis retrospective study included 175 consecutive biopsy-naïve patients (40–74 years) referred with a suspicion of PCa, but with subsequent negative investigations. Patients were grouped by age into categories ≤ 54, 55–59, 60–64, and ≥ 65 years. MpMRI sequences (T2-weighted imaging [T2WI], diffusion-weighted imaging [DWI]/apparent diffusion coefficient [ADC], and dynamic contrast-enhanced imaging [DCE]) were independently evaluated by two uro-radiologists on a proposed 4-point grading scale for background change on each sequence, wherein score 1 mirrored PIRADS-1 change and score 4 represented diffuse background change. Peripheral zone T2WI signal intensity and ADC values were also analyzed for trends relating to age.ResultsThere was a negative correlation between age and assigned background PZ scores for each mpMRI sequence: T2WI: r = − 0.52, DWI: r = − 0.49, DCE: r = − 0.45, p < 0.001. Patients aged ≤ 54 years had mean scores of 3.0 (T2WI), 2.7 (DWI), and 3.1 (DCE), whilst patients ≥ 65 years had significantly lower mean scores of 1.7, 1.4, and 1.9, respectively. There was moderate inter-reader agreement for all scores (range κ = 0.43–0.58). Statistically significant positive correlations were found for age versus normalized T2WI signal intensity (r = 0.2, p = 0.009) and age versus ADC values (r = 0.33, p = 0.001).ConclusionThe normal PZ in younger patients (≤ 54 years) demonstrates significantly lower T2WI signal intensity, lower ADC values, and diffuse enhancement on DCE, which may hinder diagnostic interpretation in these patients. The proposed standardized PZ background scoring system may help convey the potential for diagnostic uncertainty to clinicians.Key Points• Significant, positive correlations were found between increasing age and higher normalized T2-weighted signal intensity and mean ADC values of the prostatic peripheral zone.• Younger men exhibit lower T2-weighted imaging signal intensity, lower ADC values, and diffuse enhancement on dynamic contrast-enhanced imaging, which may hinder MRI interpretation.• A scoring system is proposed which aims towards a standardized assessment of the normal background PZ. This may help convey the potential for diagnostic uncertainty to clinicians.

MRI Findings of Immune Checkpoint Inhibitor-Induced Hypophysitis: Possible Association with Fibrosis.

Hypophysitis is one of the well-known adverse effects of immune checkpoint inhibitors. Immune checkpoint inhibitor-induced hypophysitis frequently causes irreversible hypopituitarism, which requires long-term hormone replacement. Despite the high frequency and clinical significance, characteristic MR imaging findings of immune checkpoint inhibitor-induced hypophysitis have not been established. In the present study, we aimed to review and extract the MR imaging features of immune checkpoint inhibitor-induced hypophysitis. This retrospective international multicenter study comprised 20 patients with melanoma who were being treated with immune checkpoint inhibitors and clinically diagnosed with immune checkpoint inhibitor-induced hypophysitis. Three radiologists evaluated the following MR imaging findings: enlargement of the pituitary gland and stalk; homogeneity of enhancement of the pituitary gland; presence/absence of a well-defined poorly enhanced area and, if present, its location, shape, and signal intensity in T2WI; and enhancement pattern in contrast-enhanced dynamic MR imaging. Clinical symptoms and hormone levels were also recorded. Enlargement of the pituitary gland and stalk was observed in 12 and 20 patients, respectively. Nineteen patients showed poorly enhanced lesions (geographic hypoenhancing lesions) in the anterior lobe, and 11 of these lesions showed hypointensity on T2WI. Thyrotropin deficiency and corticotropin deficiency were observed in 19/20 and 12/17 patients, respectively, which persisted in 12/19 and 10/12 patients, respectively, throughout the study period. Pituitary geographic hypoenhancing lesions in the anterior lobe of the pituitary gland are characteristic and frequent MR imaging findings of immune checkpoint inhibitor-induced hypophysitis. They reflect fibrosis and are useful in distinguishing immune checkpoint inhibitor-induced hypophysitis from other types of hypophysitis/tumors.

The value of MR T2WI signal intensity related parameters for predicting pathological complete response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Objective: To evaluate the value of T2WI signal intensity related parameters that can be obtained by magnetic resonance imaging (MRI) for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanved rectal cancer (LARC). Methods: Signal Intensity of Tumor (SIT) and Signal Intensity of Tumor/Muscle (SIT/M) of MR T2WI before and after neoadjuvant chemoradiotherapy of 101 patients with locally advanced rectal cancer were evaluated by two experienced readers independently. Signal Intensity of Tumor Reduction Rate (SITRR) and Signal Intensity of Tumor/Muscle Reduction Rate (SIT/MRR) were calculated. The difference of related parameters of T2WI tumor signal intensity between the pCR and the non-pCR group were analyzed. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance for predicting pCR. Results: Of the 101 patients, 18 were in pCR group and 83 were in non-pCR group. In all patients, the SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 1 were 197.0 (133.0), 144.2 (69.7), 0.4% (0.5%), 2.6 (0.6), 3.0 (2.3) and 0.4 (0.2)% in pCR group, and 227.0 (99.0), 205 (95.4), 0.1% (0.6%), 2.6 (0.6), 2.6 (1) in non-pCR group, respectively. SITpre, SITpost, SITRR, SIT/Mpre, SIT/Mpost and SIT/MRR measured by reader 2 were 193.0 (135.0), 143.0 (69.8), 0.4% (0.2%), 2.6 (0.6), 1.5 (0.5) and 0.39% (0.2%) in pCR group, and 234.0(108.0), 203(96.5), 0.1% (0.3%), 2.6 (0.6%), 1.7 (0.7) and 0.25% (0.2%) in non-pCR group, respectively. Between the pCR and non-pCR group, there were significant differences in SITpost, SIT/Mpost and SIT/MRR measured by both readers (all P<0.01), but there was no significant differences in SITpre and SIT/Mpre (P>0.05). The difference of SITRR measured by reader 1 was not statistically significant (P=0.415), while the difference of SITRR measured by reader 2 was statistically significant (P=0.001). In patients with rectal non-mucinous adenocarcinoma, SITpost, SIT/Mpost, SITRR and SIT/MRR measured by two physicians were still statistically significant between the pCR and non-pCR group (all P<0.01), but SITpre and SIT/Mpre had no significant difference (P>0.05). ROC curve analysis showed that in all patients, the area under curve (AUC) of SITpost, SIT/Mpost and SIT/MRR for predicting pCR to neoadjuvant chemoradiotherapy in locally advanced rectal cancer was 0.694-0.762, the sensitivity was 68.2%-77.3%, and the specificity was 63.6%-77.3%. In rectal non-mucinous adenocarcinoma patients, the AUC, sensitivity and specificity was 0.704-0.764, 62.7%-78.9% and 66.2%-84.2%, respectively. Conclusions: T2WI signal intensity related parameters are potential predictors for pCR in locally advanced rectal cancer after neoadjuvant chemoradiptherapy. The predictive value is higher in non-mucinous adenocarcinoma.

Neuroimaging findings of cerebral syphilitic gumma.

Cerebral syphilitic gumma is a rarely reported disease of the central nervous system. Magnetic resonance imaging (MRI) is an important diagnostic method for syphilitic gumma. The present study aimed to describe and characterize neuroimaging results from 6 patients with pathologically diagnosed cerebral syphilitic gumma. The 6 patients (age, 32–61 years) underwent brain CT and MRI, with 1 patient also undergoing whole-body 2-deoxy-2-(fluorine-18)fluoro-D-glucose-positron emission tomography/CT (18F-FDG PET/CT). Non-enhanced CT, conventional T1 weighted imaging (T1WI) and T2WI, diffusion weighted imaging (DWI) and gadolinium-enhanced T1WI images were acquired for all patients. The CT and MRI scans were retrospectively reviewed by two experienced radiologists for consensus on the location, number, size, T1WI, T2WI and DWI signal intensity characteristics, extent of vasogenic oedema, and enhancement patterns. In total, the 6 patients exhibited 10 lesions, nine of which were located in the cerebral hemisphere, primarily in the grey matter. The remaining lesion was located in the fourth ventricle, leading to mild-to-moderate hydrocephalus. The diameters of the identified 10 lesions ranged from 0.9–6.5 cm, with a mean diameter of 3.9 cm. The main feature observed in CT was low density and in MRI the features were T1WI and DWI hypointensity and T2WI hyperintensity. A single case exhibited syphilis gumma with massive haemorrhage. Ring-like or strip-like signs (n=5), accompanied by the dural tail sign (n=2) and homogeneous enhancement (n=1), were noted on T1WI with gadolinium. The 18F-FDG PET/CT performed in one patient of a cerebral syphilis gumma revealed low uptake and metabolism. The present study indicated that gadolinium-enhanced MRI combined with 18F-FDG PET/CT and laboratory examinations are helpful in distinguishing cerebral syphilitic gumma from brain tumors and infectious diseases, therefore avoiding unnecessary surgery.

MUC-1 aptamer targeted superparamagnetic iron oxide nanoparticles for magnetic resonance imaging of pancreatic cancer in vivo and in vitro experiment.

This study aims to explore the ability of magnetic resonance imaging (MRI) in mucin 1 (MUC1) modified superparamagnetic iron oxide nanoparticle (SPION) targeting human pancreatic cancer (PC). The MUC1 target-directed probe was prepared through MUC1 conjugated to SPION using the chemical method to assess its physiochemical characteristics, including hydration diameter, surface charge, and magnetic resonance signal. The cytotoxicity of MUC1-USPION was verified by MTS assay. BxPC-3 was cultured with MUC1-USPION and SPION in different concentrations. The combined condition of the targeted probes and cells were observed through Prussian blue staining. The nude mice model of pancreatic cancer was established to investigate the application of the probe. MRI was performed to determine the intensity of the signal of the transplanted tumor, while immunohistochemistry and Western blot analysis were performed to detect the expression of MUC1 after taking the transplanted tumor specimen. The particle size of the prepared molecular probe was 63.5 ± 3.2 nm, and the surface charge was 10.2 mV. Furthermore, the probe solution could significantly reduce the MRI at T2 , and the magnetic resonance transverse relaxation rate (ΔR2 ) has a linear relationship with the concentration of iron in the solution. The cell viability of MUC1-USPION in different concentrations revealed no statistical difference, according to the MTS assay. In vitro, the MRI demonstrated decreased T2WI signal intensity in both groups, especially the targeting group. In vivo, MUC1 could selectively accumulate in the nude mice model, and significantly reduce the T2 signal strength. In subsequent experiments, the expression of MUC1 was high in pancreatic cancer tissues, but low in normal pancreatic tissues, as determined by immunohistochemistry and Western blot analysis. The prepared samples can be combined with pancreatic cancer tissue specificity by in vivo imaging, providing reliable early in vivo imaging data for disease diagnosis.