Synthetic MRI to Assess Neurological Injury in Recovered COVID-19 Patients / 中山大学学报(医学科学版)

ObjectiveTo assess the microstructural involvement of gray matter in recovered COVID-19 patients using Synthetic MRI. MethodsThis study was conducted in 29 recovered COVID-19 patients， including severe group （SG， n=11） and ordinary group （OG， n=18）. Healthy volunteers matched by age， sex， BMI and years of education were selected as a healthy control group （HC=23 cases）. Each subject underwent synthetic MRI to generate quantitative T1 and T2 maps， and the T1 and T2 maps were segmented into 90 regions of interest （ROIs） using automatic anatomical labeling （AAL） mapping. T1 and T2 values for each ROI were obtained by averaging all voxels within the ROIs. The T1 and T2 values of the 90 brain regions between the three groups were compared. ResultsRelative to HC， the SG had significantly higher T2 values in bilateral orbital superior frontal gyrus， bilateral parahippocampal gyrus， bilateral putamen， bilateral middle temporal gyrus， bilateral Inferior temporal gyrus， left orbital superior frontal gyrus， left orbital inferior frontal gyrus， left gyrus rectus， left anterior cingulate and paracingulate gyri， right median cingulate and paracingulate gyri， left posterior cingulate gyrus， and left supramarginal gyrus （P＜0.05）； Relative to OG， SG showed significantly increased T2 values in the left rectus gyrus， left parahippocampal gyrus， bilateral middle temporal gyrus， and bilateral inferior temporal gyrus （P＜0.05）. Relative to HC， the T1 values of SG were significantly increased in bilateral orbital superior frontal gyrus， left rectus gyrus， left anterior cingulate and paracingulate gyri， right posterior cingulate gyrus， left parahippocampal gyrus， left lingual gyrus， left putamen， left thalamus（P＜0.05）； Relative to OG， the T1 values of SG were significantly higher in the right posterior cingulate gyrus， right calcarine fissure and surrounding cortex， and left putamen （P＜0.05）. ConclusionsEven after recovering from COVID-19， patients may still have persistent or delayed damage to their brain gray matter structure， which is correlated with the severity of the condition. SyMRI can serve as a sensitive tool to assess the extent of microstructural damage to the central nervous system， aiding in early diagnosis of the disease.

Effect of Diffuse Glioma with Precentral Gyrus Invasion on Interhemispheric Brain Activation： A Task-based FMRI Study / 中山大学学报(医学科学版)

ObjectivesTo explore the effect of diffuse glioma with precentral-gyrus invasion on fMRI activation maps by grasping T-fMRI. MethodsA total of 56 diffuse glioma patients were divided into precentral-gyrus invasion （PGI： n=21） and precentral-gyrus non-invasion （PGNI： n=35） groups. Three statistical thresholds （P value： 10-4， P1； 10-6， P2； 10-8， P3） were set to obtain the activation maps accordingly （V1， V2 and V3）. The interhemispheric and bilateral precentral gyrus activation volumes ratios （IAVR and PAVR） were calculated， respectively. The activation volumes ［△V1=V1-V2； △V2=V2-V3； △Vn （ipsilateral）/△Vn’ （contralateral）， n=1， 2］ within two statistical thresholds and the corresponding interhemispheric ratio was further compared. In addition， the associations of tumor characteristics with IAVR and PAVR were analyzed. ResultsCompared with PGNI， PGI showed significantly decreased IAVR at p1， and the same trends of PAVR in PGI at P1 and P2 （P＜0.05）. However， neither IAVR nor PAVR showed significant differences at P3. PGI showed significantly lower ratios of △V1/△V1’ than PGNI （P=0.02）， except for △V2/△V2’. Additionally， within PGI， PAVR was negatively correlated with tumor volume （P=0.043）， and the distance from the tumor to the hand-knob was positively correlated with the IAVR and PAVR （P＜0.05）. ConclusionDiffuse glioma invading eloquent areas tended to affect interhemispheric asymmetry of activation at relatively lower statistical thresholds than diffuse glioma without invasion， rather than stricter statistical thresholds. Multiple ranges of statistical thresholds were recommended to analyze T-fMRI.

Application of Sphenoid Sinus Morphological Characteristics in Sex Estimation Based on Magnetic Resonance Imaging Images / Aplicación de las Características Morfológicas del Seno Esfenoidal en la Estimación del Sexo Basada en Imágenes de Resonancia Magnética

SUMMARY: Sex determination of unknown persons plays an important role in forensic science. As most bones used for sex determination are recovered in incomplete state, it is often necessary to use bones that are recovered intact e.g., the sphenoid sinus. This study aimed to evaluate the diagnostic value of sphenoid sinuses dimensions for sex determination using Magnetic Resonance Imaging (MRI) images in Chinese adults. MRI images of 79 sphenoid sinuses (from 44 men and 35 women) were retrospectively selected. The height, anterior-posterior diameter, area, and perimeter were measured in the midsagittal view of the sphenoid sinuses. All data were subjected to descriptive and discriminative functional analysis with unpaired t-test and canonical discriminant. Comparison between male and female groups showed significant statistical differences regarding the height, anterior-posterior diameter, area, and perimeter of sphenoid sinuses. The predictive accuracy rate of the sphenoid sinus to identify sex was 63.6 % in males and 62.9 % in females with an overall accuracy of 63.3 %. This study proposed the importance of sexual dimorphism of sphenoid sinus dimensions, especially if other methods are not available. It suggested using MRI in forensics science thus obviating the complete dependence on the usage of conventional computed tomography (CT) and facilitating the study of forensic anatomy at the level of soft tissue.

La determinación del sexo de personas desconocidas juega un papel importante en la ciencia forense. Como la mayoría de los huesos utilizados para la determinación del sexo se recuperan en un estado incompleto, a menudo es necesario utilizar huesos recuperados intactos, por ejemplo, el seno esfenoidal. Este estudio tuvo como objetivo evaluar el valor diagnóstico de las dimensiones de los senos esfenoidales para la determinación del sexo utilizando imágenes de resonancia magnética en individuos adultos chinos. Se seleccionaron retrospectivamente imágenes de resonancia magnética de 79 senos esfenoidales (de 44 hombres y 35 mujeres). La altura, el diámetro anteroposterior, el área y el perímetro de los senos esfenoidales, se midieron en vista mediana sagital. Todos los datos se sometieron a análisis funcional descriptivo y discriminativo con prueba t no pareada y discriminante canónico. La comparación entre los grupos de hombres y mujeres mostró diferencias estadísticas significativas en cuanto a la altura, el diámetro anteroposterior, el área y el perímetro de los senos esfenoidales. La tasa de precisión predictiva del seno esfenoidal para identificar el sexo fue del 63,6 % en hombres y del 62,9 % en mujeres, con una precisión general del 63,3 %. Este estudio propuso la importancia del dimorfismo sexual de las dimensiones del seno esfenoidal, especialmente si no se dispone de otros métodos. Se sugiere utilizar la resonancia magnética en la ciencia forense, obviando así la dependencia total del uso de la tomografía computarizada convencional y facilitando con esto el estudio de la anatomía forense a nivel de los tejidos blandos.

AA Amyloidosis Secondary to Horton's Disease Complicated by Pulmonary Fibrosis: A Very Challenging Diagnosis and Therapy

AA amyloidosis is a classic and serious complication of many chronic inflammatory processes, whether of infectious, autoimmune, or neoplastic origin. It is frequently complicated by kidney damage, often in the form of a nephrotic syndrome. Giant cell arteritis is a common inflammatory arteritis in the elderly; however, it rarely causes AA amyloidosis. We report a rare case of Horton disease causing AA amyloidosis in an elderly patient with history of myopericarditis and repeated episodes of congestive heart failure. Patient was treated initially with dual therapy based on corticosteroids and anti TNF therapy (Tocilizumab) associated with heart failure therapy recommended by the European society of cardiology (ESC 2021 guidelines on Heart Failure). The initial outcome was favorable but later complicated by the involvement of the lungs; pulmonary fibrosis, responsible for repeated episodes of pleural effusion non controlled in spite of high dose of loop diuretics and repeated pleural punction. Patient died shortly after her second hospitalization due to respiratory insufficiency.

The eyes see what the mind knows – Interpretation of magnetic resonance imaging

Background: In 1978, the advent of magnetic resonance imaging (MRI) was a remarkable volte-face in the world of diagnostics. Employing the phenomenon of nuclear resonance enables us to exploit the properties of differential protons in living tissues. The ability of providing higher and variable contrast and the absence of ionizing radiations make it superior to computed tomography. Being the diagnostic tool of choice, it is an indispensable part of assessment of the location and characteristics of different ocular and orbital pathologies (vascular, inflammatory, and neoplastic). Purpose: The intrinsic and extrinsic properties of MRI provide multi-parametric imaging, making it of paramount importance in ophthalmological evaluation. Also, MRI-dynamic color mapping provides non-invasive and quantitative assessment of soft tissues in motion. An in-depth knowledge of the basic principle and technique of MRI aids in diagnosing as well optimal planning of surgical interventions. Synopsis: In this video, we shall be displaying the anatomical, clinical, and radiological aspects of MRI with an overlap to make it easier to understand the implications of this miraculous invention. Highlights: A good understanding of MRI analysis makes the ophthalmologists independent and helps in ruling out the differential diagnoses, exact extent and invasion, precise surgical planning and therefore, avoiding tragic outcomes. This video is an attempt to simplify and emphasize on the importance of MRI interpretation for an ophthalmologist.

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

Background: Stroke is a prevalent and potentially fatal medical condition that affects individuals worldwide. Ischemic strokes, caused by arterial blockages, are the most common type, accounting for about 80% of all cases. Hemorrhagic strokes, on the other hand, are less frequent but can have more severe consequences. Accurate and timely diagnosis of stroke is critical for effective treatment and optimal patient outcomes. In this context, diffusion-weighted imaging (DWI) has emerged as a valuable tool for identifying and monitoring ischemic stroke. This article provides an overview of the role of DWI in stroke assessment and management, with a focus on early detection and intervention. The aim of this study is to investigate the reliability of diffusion-weighted MRI (DWI) as an imaging modality in the evaluation of acute ischemic stroke. Material & Methods: This prospective cross-sectional study was conducted at the Department of Radiology and Imaging at the Combined Military Hospital (CMH) in Dhaka, Bangladesh, between June 2020 and June 2021. The study aimed to examine 120 patients clinically diagnosed with acute ischemic stroke. Prior to the study, verbal consent was obtained from all patients. The Study subjects were identified in the emergency and casualty department and had undergone an MRI of the brain in the Department of Radiology and Imaging at CMH, Dhaka. . Data were collected on pre-designed forms, and the relevant information was compiled on a master chart for statistical analysis using SPSS software. Descriptive analysis and frequency of results were presented in the form of tables, pie charts, and bar graphs. The ethical clearance of this study was obtained from the Institutional Ethics Committee of CMH, Dhaka, Bangladesh. Results: The study included 64 males and 56 females with a mean age of 65.2 ± 7.83 years. The majority of patients had an acute ischemic lesion (88.30%) in the MCA (50.0%) with small-sized lesions (41.7%) and low ADC values (90.0%). The most common clinical presentation was hemiplegia (100%), and diffusion-weighted MRI had a high diagnostic accuracy in detecting acute ischaemic lesions (96.3%). Overall, these findings highlight the importance of MRI in the evaluation of stroke patients and can guide clinical decision-making. Conclusion: The present study concluded that DWI in conjunction with ADC map MR imaging is a gold standard diagnostic modality in the evaluation and management of acute ischaemic stroke.

Echocardiographic and Etiopathogenic Features of Hypertrophic Cardiomyopathy: Casablanca University Hospital Experience

Hypertrophic cardiomyopathy (HCM) is the most common non-ischemic cardiomyopathy with a prevalence of 1:500 in the general population, based on the recognition of the phenotype. HCM is defined by the presence of increased left ventricular (LV) wall thickness that is not solely explained by abnormal loading conditions and the phenotype also includes disorganized myocyte arrangement, fibrosis, small-vessel disease, and abnormalities of the mitral valve apparatus. In particular to this pathology, we have conducted a one-year prospective study to determine clinical, echocardiographic features and etiopathogenic aspects of hypertrophic cardiomyopathy in the Casablanca university hospital. The results concluded that 50% of the causes was due to amyloidosis 35%, sarcomeric HCM and 15% Fabry disease in which 2 cases were related with pregnancy. Transthoracic echocardiography and cardia MRI plays an important role in HCM diagnosis and prognosis.

Acute abducens nerve palsy with acute disseminated encephalomyelitis-like presentation following COVID-19 vaccination

We report two adult cases of abducens nerve palsy presenting immediately (within weeks) after they received the first dose of Covishield vaccination. Magnetic resonance imaging (MRI) of the brain obtained after the onset of diplopia demonstrated demyelinating changes. The patients had associated systemic symptoms. Post-vaccination demyelination typically known as acute disseminated encephalomyelitis (ADEM) associated with several vaccines is more common in children. Although the mechanism of the nerve palsy remains unclear, it is suspected to be related to the post-vaccine neuroinflammatory syndrome. Cranial nerve palsies and ADEM-like presentations may represent part of the neurologic spectrum following COVID-vaccination in adults, and ophthalmologists should be aware of these sequelae. Although cases of sixth nerve palsy following COVID vaccination are already reported, associated MRI changes have not been reported from India.

Metronidazole: A culprit to balance and speech

In a country like India, oral metronidazole is the commonly prescribed drug of choice for entities such as amebiasis and visceral abscesses. Oral such cases, it is usually well tolerated and safe but can cause serious neurological adverse events. Peripheral neuropathy commonly encounters in practice but central nervous system toxicity is also well documented as it crosses the blood–brain barrier easily. Neurological toxicity of metronidazole may be due to prolonged administration, high doses, or high cumulative doses. Magnetic resonance imaging (MRI) of brain is the modality of choice to evaluate brain involvement. In the brain, the splenium of the corpus callosum, dentate nucleus of the cerebellum, and posterior pons involvement are commonly seen and diagnostic. Here, we have an interesting case report of a patient who was on oral metronidazole treatment for his large liver abscess, presenting with a complaint of neurological symptoms of unsteady gait, vertigo, dysdiadochokinesia, and difficulty in speech. Moreover, thus suspected as metronidazole drug toxicity and further investigated for the same, and MRI typically shows cerebellar and posterior corpus callosal involvement

The role of MRI and 18F-FDG PET/CT with respect to evaluation of pathological response in the rectal cancer patients after neoadjuvant chemoradiotherapy

Background: We aimed to evaluate the role of magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (FDG) positron emission tomography朿omputed tomography (PET-CT) in determining the correct stage and predicting the pathological response. Methods: Seventy one patients with pathologic proven rectal adenocarcinoma, clinical stage IIA-IVA, and neoadjuvant chemoradiotherapy (CRT) were evaluated retrospectively. Radiotherapy was delivered 45� Gy in 25 fractions with concomitant oral capecitabine. Pelvic MRI, colonoscopy, and 18F-FDG PET-CT were performed before the neoadjuvant treatment (NAT). After NAT, MRI and PET-CT were performed for re-evaluation. Results: The median follow-up time was 25 months (range: 3� months). Of the 71 patients who underwent NAT, 57 patients underwent surgery. Downstaging was recorded in 48 (84.2%) of 57 patients who underwent surgery. There was no statistically significant difference between both MRI and PET-CT with pathology results in terms of response evaluation. As a result of the comparison of MRI and PET-CT with pathological results; sensitivity and specificity were 91.6% (44/48) and 22.2% (2/9) for MRI, and 100% (47/47) and 12.5% (1/8) for PET-CT, respectively. Conclusion: PET-CT and MRI are effective in predicting response to NAT and predictive for the pathological response. A more accurate response can be judged when both PET-CT and MRI are executed together in restaging after NAT

Does TGFBR3 Polymorphism Increase the Risk of Silent Cerebral Infarction in Egyptian Children with Sickle Cell Disease?

Objectives To evaluate the relationship between TGFBR3 rs284875 single nucleotide polymorphism (SNP) state and silent cerebral infarction (SCI) in asymptomatic patients with sickle cell disease (SCD). Methods A cross-sectional study was conducted on 50 children with SCD above 2 y of age followed up at the hematology outpatient clinic of Alexandria University Children's Hospital in Egypt. Twenty-four healthy children were included as a control group. All patients included in the study were subjected to complete history and clinical examination. Real-time polymerase chain reaction was performed on patients and controls for identifcation of SNP rs284875 of the TGFBR3 gene. A magnetic resonance imaging (MRI) of the brain were performed only on patients for detection of SCI. Results Fifty SCD patients were enrolled (26 males and 24 females), with a median age of 10.9 y (2.3–17.8 y), and 24 children as healthy control for the studied SNP. Thirty-fve (70%) patients had homozygous SCD, while 30% had sickle ?-thalassemia. The brain MRI was normal in all the patients except for 2 patients who had features of SCI. The TGFBR3 rs284875 SNP was detected in 15 (30%) patients in the homozygous state (GG) versus only 1 (4.2%) child from the control group (p=0.003). The prevalence of SCI was low in the study population and there was no statistically signifcant relationship between the TGFBR3 rs284875 SNP status and the presence of SCI in the brain MRI (p=0.621). Conclusions This study confrmed a low prevalence of SCI in the SCD patient included in the study. The TGFBR3 rs284875 SNP did not signifcantly increase SCI among those patients.

Utilidad de la resonancia magnética en el diagnóstico del stroke agudo / Usefulness of magnetic resonance imaging in the diagnosis of acute stroke

Resumen El ataque cerebrovascular (ACV) es la primera causa de discapacidad y la tercera causa de muerte en la Argentina y en el mundo. La etiología del stroke es isquémica en su mayoría (más del 80% de los casos), siendo las causas más frecuentes las lesiones isquémicas de pequeños vasos de tipo lacunar y las tromboembólicas debido a ateroesclerosis de grandes arterias o cardioembolia. Las secuencias utilizadas en nuestro protocolo de estudio incluyen DWI, FLAIR, angio-RM 3D-TOF, SWI y FSE-T1 (tiempo aproximado de exploración de 13 minutos). Pueden observarse diferentes hallazgos en cada una de estas secuencias que son orientativos para determinar la etiología subyacente y estimar el tiempo de evolución de la lesión. En la actualidad, la trombectomía mecánica se ha convertido en el tratamiento de elección en pacientes seleccionados con accidente cerebral isquémico agudo. La transformación hemorrágica es la complicación más temida luego de la terapia de reperfusión intraarterial. La técnica de difusión de la resonancia magnética (RM) posee una mayor sensibilidad para detectar lesiones isquémicas, permite sospechar la etiología según el patrón lesional y aporta información valiosa para la selección de los pacientes candidatos a la reperfusión arterial.

Abstract Stroke or cerebrovascular attack (CVA) is the first cause of disability and the third cause of death in Argentina and in the world. The etiology of strokes is mostly ischemic (more than 80% of cases), with the most frequent causes being lacunar-type ischemic lesions of small vessels and thromboembolic lesions due to atherosclerosis of large arteries or cardioembolism. The sequences used in our study protocol include DWI, FLAIR, angio-RM 3D-TOF, SWI, and FSE-T1 (approximate scan time of 13 minutes). Different findings can be observed in each of these sequences that are indicative to determine the underlying etiology and estimate the time of evolution of the lesion. Currently, mechanical thrombectomy has become the treatment of choice in selected patients with acute ischemic stroke. Hemorrhagic transformation is the most feared complication after intra-arterial reperfusion therapy. The diffusion magnetic resonance technique is more sensitive for detecting ischemic lesions, allows one to suspect the etiology based on the lesion pattern, and provides valuable information for the selection of patients who are candidates for arterial reperfusion.

Probabilistic Tractography Between Nucleus Accumbens and Other Reward-related Brain Areas in Malay Female Adolescents

@#Introduction: Studies show that adolescents are more reward sensitive compared to other age groups. The nucleus accumbens (NAcc) has been identified as a key brain area involved in reward through its connectivity to other reward-related brain areas. Our study aimed to characterise the white matter structural connectivity of nucleus accumbens with brain areas that are most often associated with reward in female adolescents. Methods: Fifteen healthy female Malay adolescents were recruited and underwent diffusion-weighted brain scanning. Two behaviour scales were also given to verify typical reward responsiveness. Then, probabilistic tractography and NAcc segmentation were performed on the data using FMRIB Software Library (FSL). Probabilistic tractography was performed to determine the relative connection probability of nucleus accumbens (NAcc) to areas shown to be associated with reward, namely amygdala, anterior cingulate cortex (ACC), medial orbitofrontal cortex (mOFC), hippocampus, ventrolateral prefrontal cortex (vlPFC) and dorsolateral prefrontal cortex (dlPFC). Connectivity-based segmentation of NAcc was performed to determine the spatial distribution of its connectivity with the target brain areas according to the highest connection probability. Results: The highest relative connection probability was found between NAcc to mOFC, while the NAcc parcellation showed the widest distribution of connection to mOFC compared to the other five targets on both sides of the brain. Conclusion: Our findings demonstrated the strongest structural connectivity and widest distribution between NAcc and mOFC compared with other brain areas related to reward. This study’s findings could be used as baseline to compare with people with atypical reward circuit problems.

Characterization of Alar Ligament in Young Adult on 3.0T MRI: A Cross-sectional Study in IIUM Medical Centre, Kuantan

@#Introduction: Alar ligament is a paired craniocervical junction ligaments which stabilizes the atlantooccipital and atlantoaxial joints. The main purpose of the study was to compare the normal anatomy of alar ligament on MRI between male and female. The prevalence of alar ligament visualized on MRI and its characteristics were also studied apart from determining the association between the heights of respondents with alar ligament signal intensity and dimensions. Methods: Fifty healthy volunteers were studied using 3.0T MR scanner (Siemens Magnetom Spectra) by 2-mm proton density, T2 and fat-suppression sequences. Alar ligament visualization, dimensions and variability of the ligament courses, shapes and signal intensity characteristics were determined. Results: The orientation of the ligament was laterally ascending in most of the subjects (60%), predominantly oval in shaped (54%) and 67% showed inhomogenous signal. Females are 70% less likely to exhibit alar ligament signal inhomogeneity than males. There were positive correlation between height and the craniocaudal diameter of the alar ligament as well as the anteroposterior diameter, which were statistically significant (r = 0.25, n = 100, p = 0.01 and r = 0.201, n = 100, p = 0.045 respectively). Conclusion: Tremendous variability of alar ligament shows that clinical and multimodality correlation needs to be exercised, especially in evaluating alar ligament MR signal in male. Taller individuals otherwise tend to have longer and thicker ligaments. Future studies with larger samples of alar ligaments including trauma cases are also recommended to supplant a new classification system of alar ligament injury.

Difference in Brain Age Between Alzheimer's Disease and Mild Cognitive Impairment / 中国医学科学院学报

Objective To investigate the brain age differences between Alzheimer's disease(AD)and mild cognitive impairment(MCI)patients,and further explore the correlations between brain age gap(BAG)and clinical features.Methods The clinical data and radiologic findings of 132 probable AD and AD-derived MCI patients diagnosed at Beijing Tiantan Hospital,Capital Medical University from December 2018 to July 2021 were retrospectively analyzed.According to the diagnostic criteria for AD and MCI,the patients were assigned into AD and MCI groups.In addition,156 volunteers without neurological diseases and other severe diseases were recruited as the control group.The general data,Montreal cognitive assessment(MoCA)score,and mini-mental state examination(MMSE)score were compared among the three groups.The deep learning-based brain age prediction model was employed to calculate the BAGs of the three groups.Spearman correlation analysis was conducted to explore the correlations between BAG and clinical features.Results The 132 patients included 106 patients in the AD group and 26 patients in the MCI group.The MoCA and MMSE scores followed an ascending trend of AD group<MCI group<control group(all P<0.001).The predicted brain age and BAG in the AD group were higher than those in the MCI group(P=0.040,P=0.003)and control group(P=0.001,P<0.001).There was no significant difference in predicted brain age or BAG between MCI and control groups(P=0.352,P=0.224).BAG was negatively correlated with MoCA score(r=-0.341,P<0.001)and MMSE score(r=-0.324,P=0.001)in the AD group.Conclusion BAG can be used as an imaging biomarker to evaluate the degree of brain structural variation and the severity of brain injury in the patients with cognitive impairment.

Construction and internal validation of a nomogram for predicting the risk of positive prostate biopsy in MRI-negative patients / 现代泌尿外科杂志

【Objective】 To establish a nomogram model for predicting the risk of positive prostate biopsy in MRI-negative patients, and to perform the internal validation. 【Methods】 We retrospectively analyzed the clinical data of 197 MRI-negative patients who underwent prostate biopsy at our hospital, analyzed the independent predictors of positive prostate biopsy with univariate and multivariate logistic regression analysis, constructed the nomogram model and conducted internal validation. 【Results】 Multivariate logistic regression analysis showed age (P=0.003), digital rectal examination (DRE)(P=0.005), total prostate-specific antigen (tPSA) (P=0.001) and prostate volume (PV)(P<0.001) were independent risk factors of MRI-negative but prostate biopsy-positive results. The nomogram model based on all variables was established. The area under the receiver operating characteristic (ROC) curve (AUC) was 0.862, which was greater than that of tPSA (AUC=0.739), PV(AUC=0.711) and DRE(AUC=0.666) (all P<0.05). The average absolute error of the model was 1.1% after 500 internal resampling, indicating that the prediction of positive prostate biopsy was consistent with the actual situation. 【Conclusion】 The age, DRE, tPSA and PV were independent predictors of positive prostate biopsy in MRI-negative patients. The nomogram model has a good prediction performance.

Multiparametric MRI Combined with Apparent Diffusion Coefficient Histogram Analysis for Assessing Variant Histology in Urothelial Carcinoma / 中山大学学报(医学科学版)

ObjectiveTo investigate the feasibility of multiparametric MRI （mpMRI） combined with histogram analysis of apparent diffusion coefficient （ADC） in the assessment of patients with variant histology （VH） of urothelial carcinoma （UC）. MethodWe retrospectively analyzed the data of patients pathologically diagnosed with UC who underwent mpMRI in the First Affiliated Hospital of Sun Yat-sen University between March 2015 and March 2023. The patients were divided into VH group （urothelial carcinoma mixed with other histologies） and non-VH group （pure urothelial carcinoma） according to pathological results. We performed propensity score 1：1 nearest-neighbor matching on the two groups based on age and gender and 49 patients were included in each group. The regions of interest （ROIs） of the whole tumor were delineated manually by using ITK-SNAP software and Pyradiomics was applied to extract ADC histogram parameters. We compared the clinicopathological data， MRI morphological features and ADC histogram parameters between the groups. Multivariate logistic regression was used to identify independent risk factors and construct the prediction model. Receiver operating characteristic （ROC） curve analyses were performed to evaluate the diagnostic performance of these parameters for determining VH of UC. ResultsMRI morphological features including the lesion shape， vesical imaging-reporting and data system （Ⅵ-RADS）score， enhancement pattern and suspicious lymph node metastasis were markedly different between the two groups （all P < 0.05）. ADC mean， ADC median， ADC25th， ADC75th， ADC10th and ADC90th were significantly lower in patients with VH than those in non-VH group （all P<0.05）. Multivariate logistic regression analysis showed enhancement pattern， ADC25th， ADC75th and ADC mean were independent predictors （P < 0.05）. The combined model yielded the best predictive performance， with an area under the ROC curve （AUC） of 0.91 （95% CI： 0.83-0.96）. ConclusionsMpMRI combined with whole-tumor histogram analysis of ADC can serve as a reliable method for evaluating the presence of VH in UC， further to assist the clinical decision making.

MRI-derived radiomics models for diagnosis, aggressiveness, and prognosis evaluation in prostate cancer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Prostate cancer (PCa) is a pernicious tumor with high heterogeneity, which creates a conundrum for making a precise diagnosis and choosing an optimal treatment approach. Multiparametric magnetic resonance imaging (mp-MRI) with anatomical and functional sequences has evolved as a routine and significant paradigm for the detection and characterization of PCa. Moreover, using radiomics to extract quantitative data has emerged as a promising field due to the rapid growth of artificial intelligence (AI) and image data processing. Radiomics acquires novel imaging biomarkers by extracting imaging signatures and establishes models for precise evaluation. Radiomics models provide a reliable and noninvasive alternative to aid in precision medicine, demonstrating advantages over traditional models based on clinicopathological parameters. The purpose of this review is to provide an overview of related studies of radiomics in PCa, specifically around the development and validation of radiomics models using MRI-derived image features. The current landscape of the literature, focusing mainly on PCa detection, aggressiveness, and prognosis evaluation, is reviewed and summarized. Rather than studies that exclusively focus on image biomarker identification and method optimization, models with high potential for universal clinical implementation are identified. Furthermore, we delve deeper into the critical concerns that can be addressed by different models and the obstacles that may arise in a clinical scenario. This review will encourage researchers to design models based on actual clinical needs, as well as assist urologists in gaining a better understanding of the promising results yielded by radiomics.

Prognostic Value of MRI Arterial-phase Enhancement Pattern in Intrahepatic Cholangiocarcinoma Patients / 中山大学学报(医学科学版)

ObjectiveTo investigate the prognostic value of the enhancement pattern in arterial phase of preoperative Gd-EOB-DTPA enhanced magnetic resonance imaging （MRI） in evaluating the disease-free survival （DFS） and overall survival （OS） in patients undergoing curative resection for intrahepatic cholangiocarcinoma （ICC）. MethodsA retrospective analysis was done on the clinical， preoperative MRI findings and postoperative follow-up results of 93 pathologically confirmed ICC patients undergoing surgery in our hospital between January 2018 and December 2021. Kaplan-Meier survival curves and log-rank test were used to compare the DFS and OS of three groups with different arterial enhancement patterns. Cox regression analysis was used to identify the factors affecting DFS and OS. ResultsThere were significant differences in DFS and OS among the 3 groups （log-rank test， P < 0.05）. The arterial enhancement pattern was an independent predictive factor for DFS （using diffuse hyperenhancement as a reference， peripheral rim enhancement： HR = 3.550； 95%CI： 1.16 ~ 10.8； P = 0.026；diffuse hypoenhancement： HR = 3.430； 95%CI： 1.04 ~ 11.3； P = 0.042）. The arterial enhancement pattern and tumor location were predictive factors for OS （（using diffuse hyperenhancement as a reference， diffuse hypoenhancement， HR = 8.500； 95%CI： 1.09-66.3； P = 0.041； using tumor distal location as a reference， tumor perihilar location HR=2.583，95%CI： 1.14-5.83， P =0.022）. The AUC of arterial enhancement patterns in predicting 1-， 2-， and 3- year DFS were 0.722， 0.748， and 0.617， respectively； in OS， 0.720， 0.704， and 0.730， respectively， which showed better prognostic efficacy than AJCC-TNM staging system. ConclusionArterial-phase enhancement pattern of preoperative Gd-EOB-DTPA enhanced MRI is an independent predictive factor for DFS and OS of ICC patients， with a better prognostic value than AJCC-TNM staging system， and can be used for the clinical management of ICC patients.

Value for combination of T1WI star -VIBE with TWIST -VIBE dynamic contrast -enhanced MRI in distinguishing lung nodules / 中南大学学报(医学版)

OBJECTIVES@#With the increasing detection rate of lung nodules, the qualitative problem of lung nodules has become one of the key clinical issues. This study aims to evaluate the value of combining dynamic contrast-enhanced (DCE) MRI based on time-resolved imaging with interleaved stochastic trajectories-volume interpolated breath hold examination (TWIST-VIBE) with T1 weighted free-breathing star-volumetric interpolated breath hold examination (T1WI star-VIBE) in identifying benign and malignant lung nodules.@*METHODS@#We retrospectively analyzed 79 adults with undetermined lung nodules before the operation. All nodules of patients included were classified into malignant nodules (n=58) and benign nodules (n=26) based on final diagnosis. The unenhanced T1WI-VIBE, the contrast-enhanced T1WI star-VIBE, and the DCE curve based on TWIST-VIBE were performed. The corresponding qualitative [wash-in time, wash-out time, time to peak (TTP), arrival time (AT), positive enhancement integral (PEI)] and quantitative parameters [volume transfer constant (Ktrans), interstitium-to-plasma rate constant (Kep), and fractional extracellular space volume (Ve)] were evaluated. Besides, the diagnostic efficacy (sensitivity and specificity) of enhanced CT and MRI were compared.@*RESULTS@#There were significant differences in unenhanced T1WI-VIBE hypo-intensity, and type of A, B, C DCE curve type between benign and malignant lung nodules (all P<0.001). Pulmonary malignant nodules had a shorter wash-out time than benign nodules (P=0.001), and the differences of the remaining parameters were not statistically significant (all P>0.05). After T1WI star-VIBE contrast-enhanced MRI, the image quality was further improved. Compared with enhanced CT scan, the sensitivity (82.76% vs 80.50%) and the specificity (69.23% vs 57.10%) based on MRI were higher than that of CT (both P<0.001).@*CONCLUSIONS@#T1WI star-VIBE and dynamic contrast-enhanced MRI based on TWIST-VIBE were helpful to improve the image resolution and provide more information for clinical differentiation between benign and malignant lung nodules.