Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging

BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on EOB-MRI.METHODS A total of 331 patients with 356 hepatic observations were retrospectively analysed.The diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal sLIRADS.The algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations<10 mm;the single threshold for sLI-RADS C and D was 20 mm,that is,for<20 mm observations,the algorithms for<10 mm observations(sLI-RADS C)and 10-19 mm observations(sLI-RADS D)were used,respectively,while the algorithm remained unchanged for observations≥20 mm.With hepatobiliary phase(HBP)hypointensity as a major feature(MF),the final sLI-RADS(F-sLI-RADS)was formed according to the optimal sLI-RADS,and its diagnostic performance was evaluated.The times needed to classify the observations according to F-sLIRADS and LI-RADS v2018 were compared.RESULTS The optimal sLI-RADS was sLI-RADS D(with a single threshold of 20 mm),because its sensitivity was greater than that of LI-RADS v2018(89.8%vs 87.0%,P=0.031),and its specificity was not lower(89.4%vs 90.1%,P>0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classify lesions according to FsLI-RADS was shorter(51±21 s vs 73±24 s,P<0.001).CONCLUSION The use of sLI-RADS with HBP hypointensity as an MF may improve the sensitivity of HCC diagnosis and reduce lesion classification time.

High-resolution magnetic resonance imaging in the diagnosis and management of vertebral artery dissection:A case report

BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentation of VAD can be heterogeneous,with common symptoms including headache,dizziness and balance problems.Timely diagnosis and treatment are crucial for favorable outcomes;however,VAD is often missed due to its variable clinical presentation and lack of robust diagnostic guidelines.High-resolution magnetic resonance imaging(HRMRI)has emerged as a reliable diagnostic tool for VAD,providing detailed visualization of vessel wall abnormalities.CASE SUMMARY A young male patient presented with an acute onset of severe headache,vomiting,and seizures,followed by altered consciousness.Imaging studies revealed bilateral VAD,basilar artery thrombosis,multiple brainstem and cerebellar infarcts,and subarachnoid hemorrhage.Digital subtraction angiography(DSA)revealed vertebral artery stenosis but failed to detect the dissection,potentially because intramural thrombosis obscured the VAD.In contrast,HRMRI confirmed the diagnosis by revealing specific signs of dissection.The patient was managed conservatively with antiplatelet therapy and other supportive measures,such as blood pressure control and pain management.After 5 mo of rehabilitation,the patient showed significant improvement in swallowing and limb strength.CONCLUSION HR-MRI can provide precise evidence for the identification of VAD.

Analysis of The Value of Multi-Slice Spiral CT and Magnetic Resonance Imaging in The Diagnosis of Carpal Joint Injury

Objective:To analyze the value of multi-slice spiral computed tomography(CT)and magnetic resonance imaging(MRI)in the diagnosis of carpal joint injury.Methods:A total of 130 patients with suspected wrist injuries admitted to the Department of Orthopedics of our hospital from January 2023 to January 2024 were selected and randomly divided into a single group(n=65)and a joint group(n=65).The single group was diagnosed using multi-slice spiral CT,and the joint group was diagnosed using multi-slice spiral CT and magnetic resonance imaging,with pathological diagnosis as the gold standard.The diagnostic results of both groups were compared to the gold standard,and the diagnostic energy efficiency of both groups was compared.Results:The diagnostic results of the single group compared with the gold standard were significant(P<0.05).The diagnostic results of the joint group compared with the gold standard were not significant(P>0.05).The sensitivity and accuracy of diagnosis in the joint group were significantly higher than that in the single group(P<0.05).The specificity of diagnosis in the joint group was higher as compared to that in the single group(P>0.05).Conclusion:The combination of multi-slice spiral CT and MRI was highly accurate in diagnosing wrist injuries,and the misdiagnosis rate and leakage rate were relatively low.Hence,this diagnostic program is recommended to be popularized.

Altered spontaneous brain activity patterns in hypertensive retinopathy using fractional amplitude of low-frequency fluctuations:a functional magnetic resonance imaging study

AIM:To study functional brain abnormalities in patients with hypertensive retinopathy(HR)and to discuss the pathophysiological mechanisms of HR by fractional amplitude of low-frequency fluctuations(fALFFs)method.METHODS:Twenty HR patients and 20 healthy controls(HCs)were respectively recruited.The age,gender,and educational background characteristics of the two groups were similar.After functional magnetic resonance imaging(fMRI)scanning,the subjects’spontaneous brain activity was evaluated with the fALFF method.Receiver operating characteristic(ROC)curve analysis was used to classify the data.Further,we used Pearson’s correlation analysis to explore the relationship between fALFF values in specific brain regions and clinical behaviors in patients with HR.RESULTS:The brain areas of the HR group with lower fALFF values than HCs were the right orbital part of the middle frontal gyrus(RO-MFG)and right lingual gyrus.In contrast,the values of fALFFs in the left middle temporal gyrus(MTG),left superior temporal pole(STP),left middle frontal gyrus(MFG),left superior marginal gyrus(SMG),left superior parietal lobule(SPL),and right supplementary motor area(SMA)were higher in the HR group.The results of a t-test showed that the average values of fALFFs were statistically significantly different in the HR group and HC group(P<0.001).The fALFF values of the left middle frontal gyrus in HR patients were positively correlated with anxiety scores(r=0.9232;P<0.0001)and depression scores(r=0.9682;P<0.0001).CONCLUSION:fALFF values in multiple brain regions of HR patients are abnormal,suggesting that these brain regions in HR patients may be dysfunctional,which may help to reveal the pathophysiological mechanisms of HR.

Is it a normal phenomenon for pediatric patients to have brain leptomeningeal contrast enhancement on 3-tesla magnetic resonance imaging?

Determining whether sevoflurane sedation in children leads to“pseudo”prominent leptomeningeal contrast enhancement(pLMCE)on 3 Tesla magnetic resonance imaging will help reduce overdiagnosis by radiologists and clarify the pathophysiological changes of pLMCE.

Deep learning-assisted diagnosis of femoral trochlear dysplasia based on magnetic resonance imaging measurements

BACKGROUND Femoral trochlear dysplasia(FTD)is an important risk factor for patellar instability.Dejour classification is widely used at present and relies on standard lateral X-rays,which are not common in clinical work.Therefore,magnetic resonance imaging(MRI)has become the first choice for the diagnosis of FTD.However,manually measuring is tedious,time-consuming,and easily produces great variability.AIM To use artificial intelligence(AI)to assist diagnosing FTD on MRI images and to evaluate its reliability.METHODS We searched 464 knee MRI cases between January 2019 and December 2020,including FTD(n=202)and normal trochlea(n=252).This paper adopts the heatmap regression method to detect the key points network.For the final evaluation,several metrics(accuracy,sensitivity,specificity,etc.)were calculated.RESULTS The accuracy,sensitivity,specificity,positive predictive value and negative predictive value of the AI model ranged from 0.74-0.96.All values were superior to junior doctors and intermediate doctors,similar to senior doctors.However,diagnostic time was much lower than that of junior doctors and intermediate doctors.CONCLUSION The diagnosis of FTD on knee MRI can be aided by AI and can be achieved with a high level of accuracy.

Value of ultrasound and magnetic resonance imaging combined with tumor markers in the diagnosis of ovarian tumors

BACKGROUND Compare the diagnostic performance of ultrasound(US),magnetic resonance imaging(MRI),and serum tumor markers alone or in combination for detecting ovarian tumors.AIM To investigate the diagnostic value of US,MRI combined with tumor markers in ovarian tumors.METHODS The data of 110 patients with ovarian tumors,confirmed by surgery and pathology,were collected in our hospital from February 2018 to May 2023.The dataset included 60 cases of benign tumors and 50 cases of malignant tumors.Prior to surgery,all patients underwent preoperative US and MRI examinations,as well as serum tumor marker tests[carbohydrate antigen 125(CA125),human epididymis protein 4(HE4)].The aim of the study was to compare the diagnostic performance of these three methods individually and in combination for ovarian tumors.RESULTS This study found statistically significant differences in the ultrasonic imaging characteristics between benign and malignant tumors.These differences include echo characteristics,presence or absence of a capsule,blood flow resistance index,clear tumor shape,and blood flow signal display rate(P<0.05).The apparent diffusion coefficient values of the solid and cystic parts in benign tumors were found to be higher compared to malignant tumors(P<0.05).Additionally,the time-intensity curve image features of benign and malignant tumors showed significant statistical differences(P<0.05).The levels of serum CA125 and HE4 in benign tumors were lower than those in malignant tumors(P<0.05).The combined use of US,MRI,and tumor markers in the diagnosis of ovarian tumors demonstrates higher accuracy,sensitivity,and specificity compared to using each method individually(P<0.05).CONCLUSION US,MRI,and tumor markers each have their own advantages and disadvantages when it comes to diagnosing ovarian tumors.However,by combining these three methods,we can significantly enhance the accuracy of ovarian tumor diagnosis,enabling early detection and identification of the tumor’s nature,and providing valuable guidance for clinical treatment.

Structural and functional alterations in the brains of patients with anisometropic and strabismic amblyopia:a systematic review of magnetic resonance imaging studies

Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different.Therefore,we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia;this study is registered with PROSPERO(registration ID:CRD42022349191).We searched three online databases(PubMed,EMBASE,and Web of Science) from inception to April 1,2022;39 studies with 633 patients(324patients with anisometropic amblyo pia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria(e.g.,case-control designed,pee r-reviewed articles) and were included in this review.These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate co rtices during tas k-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations,respectively;these may have arisen from abnormal visual experiences.Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state,as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometro pic amblyopia and strabismic amblyopia patients.The shared dysfunction of anisometro pic amblyopia and strabismic amblyopia patients,relative to controls,is also chara cterized by reduced spontaneous brain activity in the oculomotor co rtex,mainly involving the frontal and parietal eye fields and the cerebellu m;this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia.With regards to specific alterations of the two forms of amblyo pia,anisometropic amblyo pia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients,as reflected by diffusion tensor imaging,and more significant dysfunction and structural loss in the ventral pathway.Strabismic amblyopia patients experience more attenuation of activation in the extrastriate co rtex than in the striate cortex when compared to anisometropic amblyopia patients.Finally,brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients,and the patterns of brain alterations are more limited in amblyopic adults than in childre n.In conclusion,magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alte rations in anisometropic amblyo pia and strabismic amblyopia patients;these alterations may improve our understanding of the neural mechanisms underlying amblyopia.

Review of deep learning and artificial intelligence models in fetal brain magnetic resonance imaging

Central nervous system abnormalities in fetuses are fairly common,happening in 0.1%to 0.2%of live births and in 3%to 6%of stillbirths.So initial detection and categorization of fetal Brain abnormalities are critical.Manually detecting and segmenting fetal brain magnetic resonance imaging(MRI)could be timeconsuming,and susceptible to interpreter experience.Artificial intelligence(AI)algorithms and machine learning approaches have a high potential for assisting in the early detection of these problems,improving the diagnosis process and follow-up procedures.The use of AI and machine learning techniques in fetal brain MRI was the subject of this narrative review paper.Using AI,anatomic fetal brain MRI processing has investigated models to predict specific landmarks and segmentation automatically.All gestation age weeks(17-38 wk)and different AI models(mainly Convolutional Neural Network and U-Net)have been used.Some models'accuracy achieved 95%and more.AI could help preprocess and postprocess fetal images and reconstruct images.Also,AI can be used for gestational age prediction(with one-week accuracy),fetal brain extraction,fetal brain segmentation,and placenta detection.Some fetal brain linear measurements,such as Cerebral and Bone Biparietal Diameter,have been suggested.Classification of brain pathology was studied using diagonal quadratic discriminates analysis,Knearest neighbor,random forest,naive Bayes,and radial basis function neural network classifiers.Deep learning methods will become more powerful as more large-scale,labeled datasets become available.Having shared fetal brain MRI datasets is crucial because there aren not many fetal brain pictures available.Also,physicians should be aware of AI's function in fetal brain MRI,particularly neuroradiologists,general radiologists,and perinatologists.

Does sevoflurane sedation in pediatric patients lead to“pseudo”leptomeningeal enhancement in the brain on 3 Tesla magnetic resonance imaging?

BACKGROUND Prominent leptomeningeal contrast enhancement(LMCE)in the brain is observed in some pediatric patients during sedation for imaging.However,based on clinical history and cerebrospinal fluid analysis,the patients are not acutely ill and do not exhibit meningeal signs.Our study determined whether sevoflurane inhalation in pediatric patients led to this pattern of‘pseudo’LMCE(pLMCE)on 3 Tesla magnetic resonance imaging(MRI).AIM To highlight the significance of pLMCE in pediatric patients undergoing enhanced brain MRI under sedation to avoid misinterpretation in reports.METHODS A retrospective cross-sectional evaluation of pediatric patients between 0-8 years of age was conducted.The patients underwent enhanced brain MRI under inhaled sevoflurane.The LMCE grade was determined by two radiologists,and interobserver variability of the grade was calculated using Cohen’s kappa.The LMCE grade was correlated with duration of sedation,age and weight using the Spearman rho rank correlation.RESULTS A total of 63 patients were included.Fourteen(22.2%)cases showed mild LMCE,48(76.1%)cases showed moderate LMCE,and 1 case(1.6%)showed severe LMCE.We found substantial agreement between the two radiologists in detection of pLMCE on post-contrast T1 imaging(kappa value=0.61;P<0.001).Additionally,we found statistically significant inverse and moderate correlations between patient weight and age.There was no correlation between duration of sedation and pLMCE.CONCLUSION pLMCE is relatively common on post-contrast spin echo T1-weighted MRI of pediatric patients sedated by sevoflurane due to their fragile and immature vasculature.It should not be misinterpreted for meningeal pathology.Knowing pertinent clinical history of the child is an essential prerequisite to avoid radiological overcalling and the subsequent burden of additional investigations.

A modified method for locating parapharyngeal space neoplasms on magnetic resonance images: implications for differential diagnosis

The parapharyngeal space(PPS) is an inverted pyramid-shaped deep space in the head and neck region, and a variety of tumors, such as salivary gland tumors, neurogenic tumors, nasopharyngeal carcinomas with parapharyngeal invasion, and lymphomas, can be found in this space. The differential diagnosis of PPS tumors remains challenging for radiologists. This study aimed to develop and test a modified method for locating PPS tumors on magnetic resonance(MR) images to improve preoperative differential diagnosis. The new protocol divided the PPS into three compartments: a prestyloid compartment, the carotid sheath, and the areas outside the carotid sheath. PPS tumors were located in these compartments according to the displacements of the tensor veli palatini muscle and the styloid process, with or without blood vessel separations and medial pterygoid invasion. This protocol, as well as a more conventional protocol that is based on displacements of the internal carotid artery(ICA), was used to assess MR images captured from a series of 58 PPS tumors. The consequent distributions of PPS tumor locations determined by both methods were compared. Of all 58 tumors, our new method determined that 57 could be assigned to precise PPS compartments. Nearly all(13/14; 93%) tumors that were located in the pre-styloid compartment were salivary gland tumors. All 15 tumors within the carotid sheath were neurogenic tumors. The vast majority(18/20; 90%) of trans-spatial lesions were malignancies. However, according to the ICA-based method, 28 tumors were located in the pre-styloid compartment, and 24 were located in the post-styloid compartment, leaving 6 tumors that were difficult to locate. Lesions located in both the pre-styloid and the post-styloid compartments comprised various types of tumors. Compared with the conventional ICA-based method, our new method can help radiologists to narrow the differential diagnosis of PPS tumors to specific compartments.

Fetal brain tumors:Prenatal diagnosis by ultrasound and magnetic resonance imaging

Congenital central nervous system tumors diagnosed during pregnancy are rare, and often have a poor prognosis. The most frequent type is the teratoma. Use of ultrasound and magnetic resonance image allows the suspicion of brain tumors during pregnancy. However, the definitive diagnosis is only confirmed after birth by histology. The purpose of this mini-review article is to describe the general clinical aspects of intracranial tumors and describe the main fetal brain tumors.

Value of Magnetic Resonance Imaging Texture Analysis in the Differential Diagnosis of Benign and Malignant Breast Tumors

Objective To investigate the difference in texture features on diffusion weighted imaging(DWI) images between breast benign and malignant tumors.Methods Patients including 56 with mass-like breast cancer, 16 with breast fibroadenoma, and 4 with intraductal papilloma of breast treated in the Hainan Hospital of Chinese PLA General Hospital were retrospectively enrolled in this study, and allocated to the benign group(20 patients) and the malignant group(56 patients) according to the post-surgically pathological results. Texture analysis was performed on axial DWI images, and five characteristic parameters including Angular Second Moment(ASM), Contrast, Correlation, Inverse Difference Moment(IDM), and Entropy were calculated. Independent sample t-test and Mann-Whitney U test were performed for intergroup comparison. Regression model was established by using Binary Logistic regression analysis, and receiver operating characteristic curve(ROC) analysis was carried out to evaluate the diagnostic efficiency. Results The texture features ASM, Contrast, Correlation and Entropy showed significant differences between the benign and malignant breast tumor groups(PASM= 0.014, Pcontrast= 0.019, Pcorrelation= 0.010, Pentropy= 0.007). The area under the ROC curve was 0.685, 0.681, 0.754, and 0.683 respectively for the positive texture variables mentioned above, and that for the combined variables(ASM, Contrast, and Entropy) was 0.802 in the model of Logistic regression. Binary Logistic regression analysis demonstrated that ASM, Contrast and Entropy were considered as thespecific imaging variables for the differential diagnosis of breast benign and malignant tumors.Conclusion The texture analysis of DWI may be a simple and effective tool in the differential diagnosis between breast benign and malignant tumors.

Gd-EOB-DTPA-enhanced magnetic resonance imaging for bile duct intraductal papillary mucinous neoplasms

AIM: To investigate gadolinium-ethoxybenzyldiethylenetriamine-pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI) of intraductal papillary mucinous neoplasms of the bile duct(IPMN-B). METHODS: The imaging findings of five cases of IPMN-B which were pathologically confirmed at our hospital between March 2012 and May 2013 were retrospectively analyzed. Three of these cases were diagnosed by duodenal endoscopy and biopsy pathology, and two cases were diagnosed by surgical pathology. All five patients underwent enhanced and non-enhanced computed tomography(CT), magnetic resonance cholangiopancreatography, and Gd-EOB-DTPA-enhanced MRI; one case underwent both Gd-EOB-DTPA-enhanced MRI and positron emission tomography-CT. The clinical data and imaging results for these cases were compared and are presented.RESULTS: Conventional imaging showed diffusedilatation of bile ducts and multiple intraductal polypoid and papillary neoplasms or serrated changes along the bile ducts. In two cases, Gd-EOB-DTPA-enhanced MRI revealed dilated biliary ducts and intraductal tumors, as well as filling defects caused by mucin in the dilated bile ducts in the hepatobiliary phase. GdEOB-DTPA-enhanced MRI in one case clearly showed a low-signal tumor in the hepatobiliary phase, similar to what was seen by positron emission tomographyCT. In two patients, routine inspection was unable to discern whether the lesions were inflammation or tumors. However, Gd-EOB-DTPA-enhanced MRI revealed a pattern of gradual enhancement during the hepatobiliary phase, and the signal intensity of the lesions was lower than the surrounding liver parenchyma, suggesting tissue inflammation in both cases, which were confirmed by surgical pathology. CONCLUSION: Gd-EOB-DTPA-enhanced MRI reveals the intraductal mucin component of IPMN-B in some cases and the extent of tumor infiltration beyond the bile ducts in invasive cases.

Comparison of endoscopic ultrasound, computed tomography and magnetic resonance imaging in assessment of detailed structures of pancreatic cystic neoplasms

AIM To evaluate the advantages of endoscopic ultrasound(EUS) in the assessment of detailed structures of pancreatic cystic neoplasms(PCNs) compared to computed tomography(CT) and magnetic resonance imaging(MRI).METHODS All patients with indeterminate PCNs underwent CT, MRI, and EUS. The detailed information, including size, number, the presence of a papilla/nodule, the presence of a septum, and the morphology of the pancreatic duct of PCNs were compared among the three imaging modalities. The size of each PCN was determined using the largest diameter measured. A cyst consisting of several small cysts was referred to as a motherdaughter cyst. Disagreement among the three imaging modalities regarding the total number of mother cysts resulted in the assumption that the correct number was the one in which the majority of imaging modalities indicated.RESULTS A total of 52 females and 16 males were evaluated. The median size of the cysts was 42.5 mm by EUS, 42.0 mm by CT and 38.0 mm by MRI; there was no significant difference in size as assessed among the three imaging techniques. The diagnostic sensitivity and ability of EUS to classify PCNs were 98.5%(67/68) and 92.6%(63/68), respectively. These percentages were higher than those of CT(73.1%, P < 0.001; 17.1%, P < 0.001) and MRI(81.3%, P = 0.001; 20.3%, P < 0.001). EUS was also able to better assess the number of daughter cysts in mother cysts than CT(P = 0.003); however, there was no significant difference between EUS and MRI in assessing mother-daughter cysts(P = 0.254). The papilla/nodule detection rate by EUS was 35.3%(24/68), much higher than those by CT(5.8%, 3/52) and MRI(6.3%, 4/64). The detection rate of the septum by EUS was 60.3%(41/68), which was higher than those by CT(34.6%, 18/52) and by MRI(46.9%, 30/64); the difference between EUS and CT was significant(P = 0.02). The rate of visualizing the pancreatic duct using EUS was 100%, whereas using CT and MRI it was less than 10%.CONCLUSION EUS helps visualize the detailed structures of PCNs and has many advantages over CT and MRI. EUS is valuable in the diagnosis and assessment of PCNs.

Application value analysis of magnetic resonance imaging and computed tomography in the diagnosis of intracranial infection after craniocerebral surgery

BACKGROUND Intracranial infection is a common clinical disease.Computed tomography(CT)and magnetic resonance imaging(MRI)have certain sensitivity and have good diagnostic efficacy.AIM To study the application value of MRI and CT in the diagnosis of intracranial infection after craniocerebral surgery.METHODS We selected 82 patients who underwent craniocerebral surgery(including 40 patients with intracranial infection and 42 patients without infection)during the period from April 2016 to June 2019 in our hospital.All 82 patients received CT and MRI examinations,and their clinical data were reviewed.A retrospective analysis was performed,and the coincidence rate of positive diagnosis and the overall diagnosis coincidence rate of different pathogenic infection types were measured with the two examination methods.The diagnostic sensitivity and specificity as well as the positive and negative predictive values of the two examination methods were compared.RESULTS For all types of pathogenic infections(Staphylococcus aureus,Staphylococcus hemolyticus,Staphylococcus epidermidis,and others),MRI scans had higher positive diagnostic coincidence rates than CT scans;the overall diagnostic coincidence rate,sensitivity,specificity,positive predictive value,and negative predictive values were significantly higher with MRI examinations than with CT examinations,and the differences were statistically significant(P<0.05).CONCLUSION MRI examination can accurately diagnose intracranial infection after clinical craniocerebral surgery.Compared with CT,MRI had higher diagnostic efficiency.The diagnostic sensitivity and specificity,the diagnostic coincidence rate,and the positive and negative predictive values were significantly higher with MRI than with conventional CT,which can be actively promoted.

Magnetic resonance imaging findings for differential diagnosis of perianal plexiform schwannoma: Case report and review of the literature

Plexiform schwannoma is an extremely rare variant of schwannoma, accounting for approximately 5% of cases. Due to the rarity and lack of typical symptoms, signs and radiological images, a definite diagnosis of plexiform schwannoma may not be made by clinicians prior to biopsy. In the present study, we report the first case(to our knowledge) of perianal plexiform schwannoma arising from the overlapped skin of the ischioanal fossa, and we propose an intratumorally nonenhanced circumferential capsule dividing the tumour into multiple homogeneously enhanced nodules as a magnetic resonance imaging feature to aid in the differential diagnosis of plexiform schwannoma from ancient schwannoma, cavernous haemangioma, liposarcoma and plexiform neurofibroma.

A multiple-tissue-specific magnetic resonance imaging model for diagnosing Parkinson’s disease: a brain radiomics study

Brain radiomics can reflect the characteristics of brain pathophysiology.However,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was underestimated in previous studies.In this prospective study to establish a model for PD diagnosis based on brain imaging information,we collected high-resolution T1-weighted images,R2*mapping,and quantitative susceptibility imaging data from 171 patients with PD and 179 healthy controls recruited from August 2014 to August 2019.According to the inclusion time,123 PD patients and 121 healthy controls were assigned to train the diagnostic model,while the remaining 106 subjects were assigned to the external validation dataset.We extracted 1408 radiomics features,and then used data-driven feature selection to identify informative features that were significant for discriminating patients with PD from normal controls on the training dataset.The informative features so identified were then used to construct a diagnostic model for PD.The constructed model contained 36 informative radiomics features,mainly representing abnormal subcortical iron distribution(especially in the substantia nigra),structural disorganization(e.g.,in the inferior temporal,paracentral,precuneus,insula,and precentral gyri),and texture misalignment in the subcortical nuclei(e.g.,caudate,globus pallidus,and thalamus).The predictive accuracy of the established model was 81.1±8.0%in the training dataset.On the external validation dataset,the established model showed predictive accuracy of 78.5±2.1%.In the tests of identifying early and drug-naïve PD patients from healthy controls,the accuracies of the model constructed on the same 36 informative features were 80.3±7.1%and 79.1±6.5%,respectively,while the accuracies were 80.4±6.3%and 82.9±5.8%for diagnosing middle-to-late PD and those receiving drug management,respectively.The accuracies for predicting tremor-dominant and non-tremor-dominant PD were 79.8±6.9%and 79.1±6.5%,respectively.In conclusion,the multiple-tissue-specific brain radiomics model constructed from magnetic resonance imaging has the ability to discriminate PD and exhibits the advantages for improving PD diagnosis.

Role of abdominal ultrasound for the surveillance follow-up of pancreatic cystic neoplasms: a cost-effective safe alternative to the routine use of magnetic resonance imaging

BACKGROUND Patients with pancreatic cystic neoplasms(PCN), without surgical indication at the time of diagnosis according to current guidelines, require lifetime imagebased surveillance follow-up. In these patients, the current European evidencedbased guidelines advise magnetic resonance imaging(MRI) scanning every 6 mo in the first year, then annually for the next five years, without reference to any role for trans-abdominal ultrasound(US). In this study, we report on our clinical experience of a follow-up strategy of image-based surveillance with US, and restricted use of MRI every two years and for urgent evaluation whenever suspicious changes are detected by US.AIM To report the results and cost-efficacy of a US-based surveillance follow-up for known PCNs, with restricted use of MRI.METHODS We retrospectively evaluated the records of all the patients treated in our institution with non-surgical PCN who received follow-up abdominal US and restricted MRI from the time of diagnosis, between January 2012 and January 2017. After US diagnosis and MRI confirmation, all patients underwent US surveillance every 6 mo for the first year, and then annually. A MRI scan was routinely performed every 2 years, or at any stage for all suspicious US findings.In this communication, we reported the clinical results of this alternative followup, and the results of a comparative cost-analysis between our surveillance protocol(abdominal US and restricted MRI) and the same patient cohort that has been followed-up in strict accordance with the European guidelines recommended for an exclusive MRI-based surveillance protocol.RESULTS In the 5-year period, 200 patients entered the prescribed US-restricted MRI surveillance follow-up. Mean follow-up period was 25.1 ± 18.2 mo. Surgery was required in two patients(1%) because of the appearance of suspicious features at imaging(with complete concordance between the US scan and the on-demand MRI). During the follow-up, US revealed changes in PCN appearance in 28 patients(14%). These comprised main pancreatic duct dilatation(n = 1), increased size of the main cyst(n = 14) and increased number of PNC(n = 13). In all of these patients, MRI confirmed US findings, without adding more information.The bi-annual MRI identified evolution of the lesions not identified by US in only11 patients with intraductal papillary mucinous neoplasms(5.5%), largely consisting of an increased number of very small PCN(P = 0.14). The overall mean cost of surveillance, based on a theoretical use of the European evidenced-based exclusive MRI surveillance in the same group of patients, would have been 1158.9± 798.6 € per patient, in contrast with a significantly lower cost of 366.4 ± 348.7 €(P < 0.0001) incurred by the US-restricted MRI surveillance used at our institution.CONCLUSION In patients with non-surgical PCN at the time of diagnosis, US surveillance could be a safe complementary approach to MRI, delaying and reducing the numbers of second level examinations and therefore reducing the costs.

Usefulness of prenatal magnetic resonance imaging in differential diagnosis of fetal congenital cystic adenomatoid malformation and bronchopulmonary sequestration

BACKGROUND Congenital cystic adenomatoid malformation(CCAM)and bronchopulmonary sequestration(BPS)are the most common lung diseases in fetuses.There are differences in the prognosis and treatment of CCAM and BPS,and the clinical diagnosis and treatment plan is usually prepared prior to birth.Therefore,it is quite necessary to make a clear diagnosis before delivery.CCAM and BPS have similar imaging features,and the differentiation mainly relies on the difference in supply vessels.However,it is hard to distinguish them due to invisible supplying vessels on some images.AIM To explore the application value of magnetic resonance imaging(MRI)in the differential diagnosis of fetal CCAM and BPS.METHODS Data analysis for 32 fetuses with CCAM and 14 with BPS diagnosed by prenatal MRI at Huzhou Maternal and Child Health Care Hospital and Anhui Provincial Children’s Hospital from January 2017 to January 2020 was performed to observe the source blood vessels of lesions and their direction.Pathological confirmation was completed through CT examination and/or operations after birth.RESULTS After birth,31 cases after birth were confirmed to be CCAM,and 15 were confirmed to be BPS.The CCAM group consisted of 21 macrocystic cases and 10 microcystic cases.In 18 cases,blood vessels were visible in lesions.Blood supply of the pulmonary artery could be traced in eight cases,and in 10 cases,only vessels running from the midline to the lateral down direction were observed.No lesions were found in four macrocystic cases and one microcystic case with CCAM through CT after birth;two were misdiagnosed by MRI,and three were misdiagnosed by prenatal ultrasonography.The BPS group consisted of 12 intralobar cases and three extralobar cases.Blood vessels were visible in lesions of nine cases,in four of which,the systemic circulation blood supply could be traced,and in five of which,only vessels running from the midline to the lateral up direction were observed.Three were misdiagnosed by MRI,and four were misdiagnosed by prenatal ultrasonography.CONCLUSION CCAM and BPS can be clearly diagnosed based on the origin of blood vessels,and correct diagnosis can be made according to the difference in the direction of the blood vessels,but it is hard distinguish microcystic CCAM and BPS without supplying vessels.In some CCAM cases,mainly the macrocystic ones,the lesions may disappear after birth.