Histogram analysis of MR quantitative parameters: are they correlated with prognostic factors in prostate cancer?

PURPOSE: To investigate the correlation between quantitative MR parameters and prognostic factors in prostate cancer (PCa). METHOD: A total of 186 patients with pathologically confirmed PCa who underwent preoperative multiparametric MRI (mpMRI), including synthetic MRI (SyMRI), were enrolled from two medical centers. The histogram metrics of SyMRI [T1, T2, proton density (PD)] and apparent diffusion coefficient (ADC) values were extracted. The Mann‒Whitney U test or Student's t test was employed to determine the association between these histogram features and the prognostically relevant factors. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the differentiation performance. Spearman's rank correlation coefficients were calculated to determine the correlations between histogram parameters and the International Society of Urological Pathology (ISUP) grade group as well as pathological T stage. RESULTS: Significant correlations were found between the histogram parameters and the ISUP grade as well as pathological T stage of PCa. Among these histogram parameters, ADC_minimum had the strongest correlation with the ISUP grade (r = - 0.481, p < 0.001), and ADC_Median showed the strongest association with pathological T stage (r = - 0.285, p = 0.008). The ADC_10th percentile exhibited the highest performance in identifying clinically significant prostate cancer (csPCa) (AUC 0.833; 95% CI 0.771-0.883). When discriminating between the status of different prognostically relevant factors, a significant difference was observed between extraprostatic extension-positive and -negative cancers with regard to histogram parameters of the ADC map (10th percentile, 90th percentile, mean, median, minimum) and T1 map (minimum) (p = 0.002-0.032). Moreover, histogram parameters of the ADC map (90th percentile, maximum, mean, median), T2 map (10th percentile, median), and PD map (10th percentile, median) were significantly lower in PCa with perineural invasion (p = 0.009-0.049). The T2 values were significantly lower in patients with seminal vesicle invasion (minimum, p = 0.036) and positive surgical margin (10th percentile, 90th percentile, mean, median, and minimum, p = 0.015-0.025). CONCLUSION: Quantitative histogram parameters derived from synthetic MRI and ADC maps may have great potential for predicting the prognostic features of PCa.

Radiofrequency ablation induces tumor cell dissemination in a mouse model of hepatocellular carcinoma.

BACKGROUND: We tested the hypothesis that radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) promotes tumor cell release and explored a method for reducing these effects. METHODS: A green fluorescent protein-transfected orthotopic HCC model was established in 99 nude mice. In vivo flow cytometry was used to monitor circulating tumor cell (CTC) dynamics. Pulmonary fluorescence imaging and pathology were performed to investigate lung metastases. First, the kinetics of CTCs during the periablation period and the survival rate of CTCs released during RFA were investigated. Next, mice were allocated to controls, sham ablation, or RFA with/without hepatic vessel blocking (ligation of the portal triads) for evaluating the postablation CTC level, lung metastases, and survival over time. Moreover, the kinetics of CTCs, lung metastases, and mice survival were evaluated for RFA with/without ethanol injection. Pathological changes in tumors and surrounding parenchyma after ethanol injection were noted. Statistical analysis included t-test, ANOVA, and Kaplan-Meier survival curves. RESULTS: CTC counts were 12.3-fold increased during RFA, and 73.7% of RFA-induced CTCs were viable. Pre-RFA hepatic vessel blocking prevented the increase of peripheral CTCs, reduced the number of lung metastases, and prolonged survival (all p ≤ 0.05). Similarly, pre-RFA ethanol injection remarkably decreased CTC release during RFA and further decreased lung metastases with extended survival (all p ≤ 0.05). Histopathology revealed thrombus formation in blood vessels after ethanol injection, which may clog tumor cell dissemination during RFA. CONCLUSION: RFA induces viable tumor cell dissemination, and pre-RFA ethanol injection may provide a prophylactic strategy to reduce this underestimated effect. RELEVANCE STATEMENT: RFA for HCC promotes viable tumor cell release during ablation, while ethanol injection can prevent RFA induced tumor cell release. KEY POINTS: • RFA induced the release of viable tumor cells during the ablation procedure in an animal model. • Hepatic vessel blocking can suppress tumor cells dissemination during RFA. • Ethanol injection can prevent RFA-induced tumor cell release, presumably because of the formation of thrombosis.

Unilateral bi-portal endoscopy for the treatment of thalassemia with extramedullary hematopoietic compression of the spinal cord: Two case reports.

RATIONALE: Thalassemia combined with extramedullary hematopoietic spinal cord compression is extremely rare; its ideal treatment is still controversial. Herein, we present 2 cases of thalassemia combined with extramedullary hematopoietic compression of the spinal cord wherein satisfactory results were obtained using unilateral bi-portal endoscopy (UBE). PATIENT CONCERNS: Case 1 was of a 43-year-old male who presented with a chief complaint of numbness of the left lower limb since 1-month. Case 2 involved a 23-year-old male who was admitted to the hospital with a chief complaint of numbness in both toes since 3 months and walking instability since 2 weeks. Both cases had a history of being diagnosed with thalassemia. DIAGNOSES: Computed tomography and magnetic resonance imaging showed spinal canal space-occupying lesions causing dural compression and spinal stenosis. Postoperative pathology confirmed the spinal canal lesions to be extramedullary hematopoietic tissue. INTERVENTIONS: For spinal canal decompression, UBE supplemented by blood transfusion was performed for both cases. OUTCOMES: All preoperative symptoms were relieved postoperatively; no recurrence was noted at the 6-month follow-up. LESSONS: Thalassemia combined with extramedullary hematopoiesis can lead to acute spinal cord compression. UBE significantly relieves spinal stenosis symptoms; furthermore, UBE combined with blood transfusion for spinal canal extramedullary hematopoiesis gives satisfactory results, is safe, and has a low risk of spinal cord injury.

Shear wave elastography using high-frequency linear probe for kidney transplant monitoring: A methodological study.

OBJECTIVES: To investigate the influencing factors of the image quality of shear wave elastography (SWE) performed using a high-frequency probe and its reproducibility for renal allografts. METHODS: A total of 211 patients with transplanted kidneys who underwent SWE examination performed using high-frequency or low-frequency probes were recruited for the study. The reproducibility of inter- and intraobserver agreements were analysed by using the intraclass correlation coefficient (ICC). According to the colour filling of the area of interest and imaging noise when conducting SWE, the image quality was classified as three grades: "good", "common", and "poor". A logistic regression was used to analyse the independent factors for SWE quality. RESULTS: In the comparative analysis, high frequency, transection measurement and middle pole were selected as the appropriate measurement methods. Regarding reproducibility, the ICCs) of the intra- and interobserver agreements were 0.85 and 0.77, respectively. Multivariate analysis indicated that only the skin allograft distance and kidney width were independent variables for SWE quality. In the subgroup analysis of the skin-allograft distance, the "good" and "common" rates of images decreased as the distance increased, but the CV (coefficients of variation) showed the opposite trend. The SWE quality of kidney width <5.4 cm was significantly better than that of kidney width ≥5.4 cm. CONCLUSIONS: High-frequency SWE can be used in the evaluation of transplanted kidneys due to its good repeatability and high successful measurement rate, but we should pay attention to the influence of the skin-allograft distance and kidney width on SWE quality.

Epidemiological investigation of the status of myopia in children and adolescents in Fujian Province in 2020.

PURPOSE: The 2020 epidemiological investigation of myopia in children and adolescents in Fujian Province' aimed to provide reference guidelines for the prevention and control of myopia. The purpose of the present study was to address shortfalls in the epidemiological survey of myopia in Fujian and provide a basis for government decision making. STUDY DESIGN: A cross-sectional and epidemiological investigation METHODS: Based on their levels of economic development and other economic factors, three cities in Fujian Province (Fuzhou, Xiamen, Longyan) were chosen through cluster random sampling and epidemiological investigation. Final analysis included 41,906 cases. Examinations including visual acuity and mydriatic optometry were performed on all subjects. RESULTS: The overall proportion of myopia was 63.35% in boys and 70.55% in girls living in Fujian in 2020. The proportions of myopia in Xiamen and Longyan were similar; both cities showed a higher proportion of myopic cases than Fuzhou. The proportion of girls with myopia was higher than boys. The proportion of primary and middle school students with myopia was higher in economically developed regions compared with underdeveloped regions. The proportion of urban students with myopia was higher than in suburban students. Analysis showed that the prevalence of myopia increased with age. Interestingly, the prevalence of myopia was higher in children born in June and August than in children born in other months. CONCLUSION: Children and adolescents in Fujian have a high rate of myopia which increases as the school grade increases. The better the economic conditions are, the higher the myopic rate. In addition, the myopic rate is higher in girls in and students born in June and August. The government, schools, hospitals, and parents should be alerted to this issue and coordinate to control the risk of myopia exacerbation and improve eyesight conditions of students in Fujian Province.

USP7- and PRMT5-dependent G3BP2 stabilization drives de novo lipogenesis and tumorigenesis of HNSC.

GTPase-activating protein-binding protein 2 (G3BP2) is a key stress granule-associated RNA-binding protein responsible for the formation of stress granules (SGs). Hyperactivation of G3BP2 is associated with various pathological conditions, especially cancers. Emerging evidence indicates that post-translational modifications (PTMs) play critical roles in gene transcription, integrate metabolism and immune surveillance. However, how PTMs directly regulate G3BP2 activity is lacking. Here, our analyses identify a novel mechanism that PRMT5-mediated G3BP2-R468me2 enhances the binding to deubiquitinase USP7, which ensures the deubiquitination and stabilization of G3BP2. Mechanistically, USP7- and PRMT5-dependent G3BP2 stabilization consequently guarantee robust ACLY activation, which thereby stimulating de novo lipogenesis and tumorigenesis. More importantly, USP7-induced G3BP2 deubiquitination is attenuated by PRMT5 depletion or inhibition. PRMT5-activity dependent methylation of G3BP2 is required for its deubiquitination and stabilization by USP7. Consistently, G3BP2, PRMT5 and G3BP2 R468me2 protein levels were found positively correlated in clinical patients and associated with poor prognosis. Altogether, these data suggest that PRMT5-USP7-G3BP2 regulatory axis serves as a lipid metabolism reprogramming mechanism in tumorigenesis, and unveil a promising therapeutic target in the metabolic treatment of head and neck squamous carcinoma.

LncRNA and mRNA expression profiles in brown adipose tissue of obesity-prone and obesity-resistant mice.

Obesity-prone or obesity-resistant phenotypes can exist in individuals who consume the same diet type. Brown adipose tissue functions to dissipate energy in response to cold exposure or overfeeding. Long noncoding RNAs play important roles in a wide range of biological processes. However, systematic examination of lncRNAs in phenotypically divergent mice has not yet been reported. Here, the lncRNA expression profiles in BAT of HFD-induced C57BL/6J mice were investigated by high-throughput RNA sequencing. Genes that play roles in thermogenesis and related pathways were identified. We found lncRNA (Gm44502) may play a thermogenic role in obesity resistance by interacting with six mRNAs. Our results also indicated that seven differentially expressed lncRNAs (4930528G23Rik, Gm39490, Gm5627, Gm15551, Gm16083, Gm36860, Gm42002) may play roles in reducing heat production in obesity susceptibility by interacting with seven differentially expressed mRNAs. The screened lncRNAs may participate in the pathogenesis of weight regulation and provide insight into obesity therapy.

CLP1 is a Prognosis-Related Biomarker and Correlates With Immune Infiltrates in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic, heterogeneous autoimmune disease with a high disability rate that seriously affects society and individuals. However, there is a lack of effective and reliable diagnostic markers and therapeutic targets. In this study, we identified diagnostic markers of RA based on RNA modification and explored its role as well as degree of immune cell infiltration. We used the gene expression profile data of three synovial tissues (GSE55235, GSE55457, GSE77298) from the Gene Expression Omnibus (GEO) database and the gene of 5 RNA modification genes (including m6A, m1A, m5C, APA, A-1), combined with cluster analysis, identified four RNA modifiers closely related to RA (YTHDC1, LRPPRC, NOP2, and CLP1) and five immune cells namely T cell CD8, CD4 memory resting, T cells regulatory (Tregs) Macrophages M0, and Neutrophils. Based on the LASSO regression algorithm, hub genes and immune cell prediction models were established respectively in RA and a nomogram based on the immune cell model was built. Around 4 key RNA modification regulator genes, miRNA-mRNA, mRNA-TF networks have been established, and GSEA-GO, KEGG-GSEA enrichment analysis has been carried out. Finally, CLP1 was established as an effective RA diagnostic marker, and was highly positively correlated with T cells follicular helper (Tfh) infiltration. On the other hand, highly negatively correlated with the expression of mast cells. In short, CLP1 may play a non-negligible role in the onset and development of RA by altering immune cell infiltration, and it is predicted to represent a novel target for RA clinical diagnosis and therapy.

Study on the Optic Nerve Fiber Layer Thickness and Changes in Blood Flow in Myopic Children.

OBJECTIVE: The present study aims to observe the optic nerve fiber layer thickness and blood flow density in the papillary area and investigate the effects of axial length (AL) and the refractive state of the optic papilla blood flow density in children with different refractive conditions. METHODS: The present study was a clinical control study. The right eyes of 204 minors aged 6-17 years were studied. The eyes were divided into four groups according to myopic refractive states. OCTA analyzed the data to compare the radial peripapillary capillary (RPC) density and the difference in the retinal nerve fiber layer (RNFL) thickness adjacent to the optic papilla between the four refraction groups. RESULTS: The intra-optic disc blood flow density was significantly and negatively correlated with the AL and was negatively correlated with the AL in the inferior temporal quadrants. The RNFL in the superior, nasal, and inferior quadrants was negatively correlated with the AL. The RNFL in the temporal quadrant was positively correlated with the AL. CONCLUSION: Our present study revealed that aAs myopia increased and the AL grew in children, the blood density of the entire image of the optic papilla, in the optic disc, and the retinal capillaries in the inferior parapapillary and temporal quadrant would change significantly. With increasing AL, a significant decrease in the intra-disc and para-disc RNFL was observed in the superior, nasal, and inferior quadrants, while a substantial increase in RNFL was observed in the temporal quadrant.

A Comparative Study of Macular and Choroidal Thickness and Blood-Flow Parameters in Patients with Intermediate and Simple Juvenile Moderate Myopia.

OBJECTIVE: This study aimed to compare the macular and choroidal thicknesses and blood-flow parameters of patients with intermediate and simple juvenile moderate myopia in order to provide a greater understanding of the pathogenesis of myopia and a basis for its prevention. METHODS: Participants were selected from patients under the age of 18 with moderate myopia who were treated in our ophthalmic clinic between June and December 2019. Seventy-five right eyes were selected from participants with a mean spherical equivalent ranging from -6.0 to -3.0 D. These samples were divided into two groups based on eye axial length (AL). The thicknesses of the macula and choroid, the area of the foveal avascular zone (FAZ), and the blood flow density of the macular capillaries were measured, intergroup comparison was conducted. RESULTS: The average area of the FAZ was larger in the intermediate group than in the simple group. PERIM in the upper half was lower in the intermediate group than in the simple group, and the blood-flow density in the lower half of the macular area was higher in the simple group than in the intermediate group. The blood-flow density within 1 mm of the fovea centralis and the downward blood-flow density were higher in the intermediate group than in the simple group. The thicknesses of the lower part of the FAZ, the choroid of the fovea centralis, and the choroid under the retina were all larger in the intermediate group than in the simple group. CONCLUSION: The area of the FAZ in patients with intermediate juvenile moderate myopia is larger than that in patients with simple myopia; the choroid in the fovea of macula compensatorily increases, and blood flow density also increases; the thickness of the choroid under the retina increases with myopia.

Malignancy risk stratification and FNA recommendations for thyroid nodules: A comparison of ACR TI-RADS, AACE/ACE/AME and ATA guidelines.

OBJECTIVE: To compare diagnostic performance and malignancy risk stratification among guidelines set forth by the American Thyroid Association (ATA) in 2015, the American Association of Clinical Endocrinologists (AACE), the American College of Endocrinology (ACE) and the Association Medici Endocrinologi (AME) in 2016, and the American College of Radiology (ACR) in 2017. METHODS: The retrospective study was approved by the hospital ethics committee, and the informed consent requirement was waived. From October 2015 to March 2016, a total of 230 patients with 230 consecutive thyroid nodules were enrolled in this study. Each nodule was classified by one junior and one senior radiologist separately according to ACR TI-RADS, AACE/ACE/AME and ATA guidelines. The malignancy diagnostic performance and the number of FNA recommendations were pairwise compared among three guidelines using chi-square tests. RESULTS: Of the 230 thyroid nodules, 137 were malignant, and 93 were benign. However, 19.6% of the nodules (45 of 230) did not match any pattern using the ATA guidelines but with a high risk of malignancy (68.9%). The ACR TI-RADS derived the highest diagnostic performance, from both junior radiologist (AUC 0.815) and senior radiologist (AUC 0.864). The ACR guidelines also showed the greatest level of sensitivity (junior: 86.1%, senior: 94.9%), compared with AACE/ACE/AME and ATA guidelines. The number of thyroid nodules recommended to fine-needle aspiration (FNA) was the lowest (37.8%, 40.4%) by ACR TI-RADS, and meanwhile, the malignant detection rate within these nodules was highest (64.4%, 68.8%). CONCLUSIONS: The ACR guidelines present a higher level of diagnostic indicators and may offer a meaningful reduction in FNA recommendations with a higher malignancy detection rate.

Effect of Conditioned Medium from Human Umbilical Cord-Derived Mesenchymal Stromal Cells on Rejuvenation of Nucleus Pulposus Derived Stem/Progenitor Cells from Degenerated Intervertebral Disc.

BACKGROUND AND OBJECTIVES: Mesenchymal stromal cells (MSCs)-based treatment for degeneration of intervertebral disc (IVD) has been proposed recently. We here addressed whether MSC secreted factors can rejuvenate nucleus pulposus- derived stem/progenitor cells from degenerated disc (D-NPSCs) in vitro. METHODS AND RESULTS: We analyzed the expression of MSCs and NP cell specific surface markers, pluripotency related genes, multilineage potential and cell proliferative capacity of D-NPSCs upon incubation with the conditioned medium which was collected from the umbilical cord derived MSCs (UCMSCs). Our results indicated that the conditioned medium restore the stemness of D-NPSCs by up-regulating the expression level of CD29 and CD105, pluripotency related genes OCT4 and Nanog, and NP progenitor marker Tie2. The increased stemness was accompanied by promoted cell proliferative capacity and improved osteogenic and chondrogenic differentiation potential. CONCLUSIONS: Our findings suggested that the UCMSCs derived conditioned medium might be used to rejuvenate the degenerated NP stem/progenitor cells.

Percutaneous radiofrequency ablation of adrenal metastases from hepatocellular carcinoma: a single-center experience.

BACKGROUND: The prognosis of adrenal metastases (AM) from hepatocellular carcinoma (HCC) with surgical contraindication was poor. This study evaluated the feasibility, safety and treatment efficacy of percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) for the local treatment of AM originated from HCC. METHODS: A retrospective study was carried out on 22 patients (21 male and 1 female, mean age, 53.0 ± 13.0 years) who had single AM (mean diameter, 4.0 ± 1.8 cm, range, 1.7-8.0 cm) originated from HCC and received US-guided percutaneous RFA at our institution. The diagnosis was established on typical radiologic findings. The primary technical success was defined as the tumour being completely ablated in the first RFA session. The secondary technical success was defined as tumour residual left from the first ablation was completely ablated by a second ablation session. Local tumour progression (LTP) and overall survival (OS) were estimated by using Kaplan-Meier analysis. RESULTS: A total of 25 ablation sessions were performed. The primary technical success and the secondary technical success were 77.3% (17 of 22) and 86.4% (19 of 22), respectively, with the major complication rate at 4.5% (1 of 22). The median follow-up period after RFA was 10 months (3-55 months). During the follow-up period, five patients were detected LTP. The LTP at 3, 6, and 12 months were 15.8, 26.3, and 26.3%, respectively. Nine patients died of distant extra-adrenal metastases and another five of liver failure due to HCC. The OS at 6, 12, 24 months after RFA for AM were at 79.7, 52.6, and 32.9%, respectively. CONCLUSION: Percutaneous US-guided RFA in the treatment of AM originated from HCC is feasible, safe and effective.

Non-enhanced Pattern on Contrast-Enhanced Ultrasound in the Local Efficacy Assessment of Irreversible Electroporation Ablation of Pancreatic Adenocarcinoma.

The objective was to evaluate the diagnostic value of contrast-enhanced ultrasound in the assessment of the local efficacy after irreversible electroporation (IRE) ablation of pancreatic adenocarcinoma 1 mo after ablation. Fifteen patients with pancreatic adenocarcinoma were treated with IRE and then examined by contrast-enhanced ultrasound 1 mo after ablation. The contrast agent was SonoVue. Technical efficacy was assessed at 3 mo after IRE and classified as technical efficiency (TE) and technical inefficiency (TIE). Diagnostic performance was analyzed using a receiver operating characteristic curve. Ten patients were considered as having TE, and five, TIE. Complete non-enhancement was observed in seven ablation zones (70.0%) in the TE group, and peripheral heterogeneous enhancement, in all five ablation zones (100.0%) in the TIE group. The non-enhancement pattern differed significantly between the TE and TIE groups (p = 0.026), with significant correlation with technical efficacy (p = 0.007). The area under the receiver operating characteristic curve was 0.85 (p = 0.008, 95% confidence interval: 0.65-1.05). A non-enhancement pattern using contrast-enhanced ultrasound was useful in the assessment of local efficacy after IRE ablation of pancreatic adenocarcinoma.

Regenerative potential of human nucleus pulposus resident stem/progenitor cells declines with ageing and intervertebral disc degeneration.

Numerous studies have demonstrated the presence of resident nucleus pulposus stem/progenitor cells (NPSCs) in the tissue of the intervertebral disc (IVD). However, the cellular identity of NPSCs during IVD degeneration and ageing are poorly defined at present, despite significant progress in the understanding of NPSC biology. In the present study, NPSCs were isolated from human degenerated IVD and were characterized by flow cytometry, gene expression assays and proliferation and multipotency analysis. The results of the present study demonstrated that NPSCs isolated from human degenerated IVD may be divided into two groups according to the expression of mesenchymal stem cell (MSC) surface markers: The high expression of MSC surface markers group (H­NPSCs) was highly positive for CD29, CD44, CD73, CD90 and CD105 at rates >95%, and the low expression of MSC markers surface markers group (L­NPSCs), with the expression of CD29 and CD105 exhibiting individual variability, however, all at rates <95%. The donors for H­NPSCs were aged <20 years, while the majority of donors for L­NPSCs were aged >25 years, with one exception aged <20 years. The results highlighted that the low expression of MSC surface markers in NPSCs from aged and degenerated NP tissues were associated with a low rate of proliferation and reduced differentiation potential, as well as downregulation of the NP progenitor marker Tie2 and higher expression of NP cell­specific markers. These findings demonstrated that the regenerative potential of human NPSCs declines with ageing and degeneration of the IVD.

Falcine Sinus: Incidence and Imaging Characteristics of Three-Dimensional Contrast-Enhanced Thin-Section Magnetic Resonance Imaging.

Objective: To evaluate the incidence, characteristics, and variations of the falcine sinus with contrast-enhanced three-dimentional (3D) thin-section magnetic resonance (MR) images. Materials and Methods: A retrospective review identified 1531 patients (745 males and 786 females, 2 months to 85 years) who underwent cranial MR imaging including T1-weighted imaging, T2-weighted imaging, T2-weighted fluid-attenuated inversion recovery, contrast-enhanced 3D thin-section sagittal scans, and MR venography, from June 2014 to January 2016. The incidence, characteristics of the falcine sinus, and coexisted intracranial lesions were confirmed by two neuroradiologists. Results: Falcine sinuses were identified in 81 (38 males and 43 females) cases (5.3%, 81/1531, 5 months to 76 years of age) with calibers ranging from 2.3 mm to 17.0 mm. Three major forms of falcine sinuses were defined: arch-like (n = 47), stick-like (n = 22), and bifurcated (n = 12). Persistent falcine sinuses were found in 57 cases, among which 3 cases showed complicated cerebral anomalies, and 2 cases showed smaller straight sinuses. Recanalization of falcine sinuses were found in 24 cases, including 17 cases with tumor compression, 6 cases with cerebral venous sinus thrombosis, and one case with hypertrophic meningitis. Conclusion: Falcine sinus is not as rare as has been reported previously. Most falcine sinuses are not associated with congenital cerebral abnormalities. Diseases that cause increased pressure in the venous sinus may lead to recanalization of falcine sinus. Illustrating the characteristics of falcine sinus may prompt a more comprehensive understanding and diagnosis of associated diseases, and avoid potential surgical damage in the future.

Ovarian collision tumors: imaging findings, pathological characteristics, diagnosis, and differential diagnosis.

Collision tumors are uncommon neoplasms in which elements of differing histologic origins coexist in a single mass. Ovarian collision tumors are a rare subtype of such lesions. The identification of collision tumors by radiologic examinations is essential to ensure that comprehensive biopsies are performed to guide appropriate treatments. According to the clinical and imaging findings of 12 patients and reviews of previous studies, ovarian collision tumors are mixtures of different combinations of epithelial tumors, germ cell tumors, and sex-cord-stromal tumors. The smaller tumors are usually located inside ("nested tumor") or on the wall ("back to back") of the larger tumors. Each type of ovarian collision tumors presents specific CT/MRI features in accordance with their histologic origins and collision patterns. Knowledge of the imaging features of ovarian collision tumors is crucial to aid preoperative diagnostic accuracy.

Diffusion-Weighted and Magnetization Transfer Imaging in Testicular Spermatogenic Function Evaluation: Preliminary Results.

PURPOSE: To assess the use of functional magnetic resonance imaging (MRI), including diffusion-weighted MRI (DWI) and magnetization transfer MRI (MTI) in evaluating male infertility. MATERIALS AND METHODS: Sixteen men with testicular spermatogenesis hypofunction confirmed by percutaneous testis biopsy and 31 volunteers (control group B, age range: 20-40 years) with normal semen analysis including younger (By, n = 15, age range: 20-30 years) and older (Bo, n = 16, age range: 31-40 years) men underwent pelvic 3T MRI, including DWI and MTI. Apparent diffusion coefficient (ADC) and magnetization transfer ratio (MTR) were compared. RESULTS: The ADCs in 32 testes of 16 patients (0.497 ± 0.037 × 10-3 mm2 /s) were significantly (P < 0.001) higher than that of control group B (0.460 ± 0.031 × 10-3 mm2 /s), group By (0.453 ± 0.018 × 10-3 mm2 /s), and group Bo (0.461 ± 0.034 × 10-3 mm2 /s), whereas the MTRs were significantly lower than that of group B (16.14 ± 4.20), group By (17.88 ± 2.00), and group Bo (15.09 ± 4.28) (P < 0.001). CONCLUSION: Functional MRI, including DWI and MTI, appears promising for evaluating male infertility with higher ADC and lower MTR in testicular spermatogenesis hypofunction. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:186-190.

Comparison of Early Submucosal Enhancement and Tumor Stalk in Staging Bladder Urothelial Carcinoma.

OBJECTIVE: The purpose of this study was to compare the efficacy of submucosal enhancement on dynamic contrast-enhanced MRI (DCE-MRI) and detection of a stalk on DWI for differentiating stage T1 from stage T2 bladder urothelial carcinoma. SUBJECTS AND METHODS: Our prospective study was approved by the institutional medical ethics committee and informed consent was obtained from all patients. Fifty-nine patients (92 tumors in total) with urothelial bladder cancer underwent MRI within 2 weeks before surgery. Two image sets of T2-weighted MRI with DWI and T2-weighted with DCE-MRI were interpreted independently at 2-week intervals by two uroradiologists without any knowledge of the surgical or histologic findings. The tumor was categorized as stage T1 or lower when a stalk was evident at the tumor base on DWI or when continuous linear submucosal enhancement was detected in the early phase of DCE-MRI. Tumors without stalks or with discontinuous linear submucosal enhancement were categorized as stage T2. RESULTS: Of the 42 tumors with stalks on DWI, 41 showed continuous and one had discontinuous submucosal enhancement on DCE-MRI. In 50 carcinomas without stalks on DWI, submucosal enhancement was absent in 34, continuous in 12, and discontinuous in four. The staging accuracy of DWI (91.3%, 84/92) and DCE-MRI (91.3%, 84/92) was improved to 94.6% (87/92) by combining the interpretations of both DWI and DCE-MRI. CONCLUSION: Submucosal linear enhancement under the tumor base on DCE-MRI complements tumor stalk detection on DWI for differentiating stage T1 from stage T2 bladder urothelial carcinoma.