Imaging Features and Risk Factors of Pancreatic Cystic Lesions Complicating Autoimmune Pancreatitis: A Retrospective Study.

OBJECTIVE: This study aimed to explore the imaging features and risk factors of PCLs complicating AIP, and investigate its prognosis through continuous imaging follow-up. PATIENTS AND METHODS: Patients who were diagnosed with AIP from January 2014 to December 2020 in our hospital were recruited. We analyzed the CT and MRI features of PCLs complicating AIP, and investigated its prognosis through imaging follow-up. We also compared subjects with and without PCLs using clinical, laboratory, and imaging data; the related risk factors associated with PCLs were investigated in a multivariate logistic regression analysis. RESULTS: In this group, 16 patients had PCLs and 86 did not. A total of 43 PCLs larger than 5mm were found in 15 patients. Among these PCLs, 35 showed homogeneous signal (density); one, bleeding; three, linear separation; and four, small focal low signal on T2WI. Eight patients with 23 PCLs appeared for the follow-up after steroid treatment. Short-term follow-up showed that 11 PCLs disappeared, nine reduced, one unchanged and two enlarged. Of the 12 PCLs that did not disappear, 10 PCLs disappeared at long-term follow-up, except for two reduced PCLs were not re-examined. Logistic regression analysis showed that drinking history was an independent risk factor, age ≥ 65 years was an independent protective factor for PCLs complicating AIP. CONCLUSION: The imaging features of PCLs complicating AIP are various, which can be single or multiple, most of them are homogeneous, and some lesions may be accompanied by hemorrhage, separation and necrosis. Age ≥ 65 years and avoiding drinking may help to reduce the occurrence of these lesions.

Spontaneous remission of autoimmune pancreatitis: Four case reports.

BACKGROUND: Autoimmune pancreatitis (AIP) is a particular type of chronic pancreatitis, and steroid treatment of AIP is effective. Spontaneous remission (SR) of AIP without steroids is relatively rare. The international consensus for the treatment of autoimmune pancreatitis suggests that patients with AIP with obstructive jaundice, abdominal pain, and back pain related to the pancreas or the bile duct should be treated with steroids; most asymptomatic patients with AIP may improve without steroids. However, in our clinical work, we found that the clinical characteristics of AIP patients with SR vary. Four of these cases are described here. In addition, to our knowledge, there is no previously published report of dynamic imaging before and after SR of AIP at present. CASE SUMMARY: We present the cases of four patients with AIP (two females and two males) in which the AIP improved spontaneously without steroid treatment. Two patients were asymptomatic, one patient had abdominal pain with obstructive jaundice, and one patient had intermittent right upper abdominal pain. Three patients presented with localized pancreatic enlargement and one with diffuse pancreatic enlargement. In addition to the pancreatic lesions, bile duct involvement was seen in two patients, and no extra-pancreatic organ involvement was found in the other two patients. The serum IgG4 level of all patients was more than twice the normal level. After SR in the four patients, the affected pancreases exhibited three types of image features: Return to normal, progressive fibrosis, and atrophy and calcification. CONCLUSION: The clinical features of SR in our four patients with AIP differ, but the imaging findings share some characteristics. After SR, in some cases the affected pancreas could return to normal, although some patients suffer from progressive fibrosis and atrophy as well as calcification.

Assessment of liver fibrosis with liver and spleen magnetic resonance elastography, serum markers in chronic liver disease.

BACKGROUND: The accurate assessment of liver fibrosis is essential for patients with chronic liver disease. A liver biopsy is an invasive procedure that has many potential defects and complications. Therefore, noninvasive assessment techniques are of considerable value for clinical diagnosis. Liver and spleen magnetic resonance elastography (MRE) and serum markers have been proposed for quantitative and noninvasive assessment of liver fibrosis. This study aims to compare the diagnostic performance of liver and spleen stiffness measured by MRE, fibrosis index based on the 4 factors (FIB-4), aspartate aminotransferase-to-platelet ratio index (APRI), and their combined models for staging hepatic fibrosis. METHODS: One hundred and twenty patients with chronic liver disease underwent MRE scans. Liver and spleen stiffness were measured by the MRE stiffness maps. Serum markers were collected to calculate FIB-4 and APRI. Liver biopsies were used to identify pathologic grading. Spearman's rank correlation analysis evaluated the correlation between the parameters and fibrosis stages. Receiver operating characteristic (ROC) analysis evaluated the performance of the four individual parameters, a liver and spleen stiffness combined model, and an all-parameters combined model in assessing liver fibrosis. RESULTS: Liver stiffness, spleen stiffness, FIB-4, and APRI were all correlated with fibrosis stage (r=0.87, 0.64, 0.65, and 0.51, respectively, all P<0.001). Among the 4 individual diagnostic markers, liver stiffness showed the highest values in staging F1-4, F2-4, F3-4 and F4 (AUC =0.89, 0. 97, 0.95, and 0.95, all P<0.001). The AUCs of the liver and spleen stiffness combined model in the F1-4, F2-4, F3-4, and F4 staging groups were 0.89, 0.97, 0.95, and 0.96, respectively (all P<0.001). The corresponding AUCs of the all-parameters combined model were 0.90, 0.97, 0.95, and 0.96 (all P<0.001). The AUCs of the liver and spleen stiffness combined model were significantly higher than those of APRI, FIB-4 in the F2-4, F3-4, and F4 staging groups (all P<0.05). Both combined models were not significantly different from liver stiffness in staging liver fibrosis (all P>0.05). CONCLUSIONS: Liver stiffness measured with MRE had better diagnostic performance than spleen stiffness, APRI, and FIB-4 for fibrosis staging. The combined models did not significantly improve the diagnostic value compared with liver stiffness in staging fibrosis.

Locally advanced rectal cancer: predicting non-responders to neoadjuvant chemoradiotherapy using apparent diffusion coefficient textures.

PURPOSE: The purpose of the study is to evaluate whether apparent diffusion coefficient (ADC) textures could identify patient with locally advanced rectal cancer (LARC) who would not respond to neoadjuvant chemoradiotherapy (NCRT). METHOD: Twenty-six patients who underwent MRI including diffusion-weighted imaging at a 3.0 T system before NCRT were enrolled. Texture analysis of pre-therapy ADC mapping was carried out, and a total of 133 ADC textures as well as routine mean ADC value of the primary tumor were extracted for each patient. Texture parameters and mean ADC were compared between responsive group and non-responsive group. Logistic regression was used to determine the independent predictors for non-responders. Receiver operating characteristic curve (ROC) was performed to evaluate the predictive performance of the significant parameters. RESULTS: Eighteen of the 133 texture parameters significantly differed between responsive and non-responsive groups (p < 0.05). Further, energy variance and SdGa47 were identified as independent predictors for non-responders to NCRT; this logistic model achieved an area under the curve (AUC) of 0.908. CONCLUSION: Texture analysis based on pre-therapy ADC mapping could potentially be helpful to identify patients with LARC who would not respond to NCRT.

CT findings of persistent pure ground glass opacity: can we predict the invasiveness?

BACKGROUND: To investigate whether CT findings can predict the invasiveness of persistent cancerous pure ground glass opacity (pGGO) by correlating the CT imaging features of persistent pGGO with pathological changes. MATERIALS AND METHODS: Ninety five patients with persistent pGGOs were included. Three radiologists evaluated the morphologic features of these pGGOs at high resolution CT (HRCT). Binary logistic regression was used to assess the association between CT findings and histopathological classification (pre-invasive and invasive groups). Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of diameters. RESULTS: A total of 105 pGGOs were identified. Between pre-invasive (atypical adenomatous hyperplasia, AAH, and adenocarcinoma in situ, AIS) and invasive group (minimally invasive adenocarcinoma, MIA and invasive lung adenocarcinomas, ILA), there were significant differences in diameter, spiculation and vessel dilatation (p<0.05). No difference was found in air-bronchogram, bubble- lucency, lobulated-margin, pleural indentation or vascular convergence (p>0.05). The optimal threshold value of the diameters to predict the invasiveness of pGGO was 12.50mm. CONCLUSIONS: HRCT features can predict the invasiveness of persistent pGGO. The pGGO with a diameter more than 12.50mm, presences of spiculation and vessel dilatation are important factors to differentiate invasive adenocarcinoma from pre-invasive cancerous lesions.

Characterization of resting-state fMRI-derived functional connectivity in patients with deficiency versus excess patterns of major depression.

OBJECTIVE: Patients with major depression (MD) experience a variety of emotional and mental problems accompanied by characteristic clinical symptoms. Based on traditional Chinese medicine (TCM) notions, the clinical appearance of MD can be divided into two syndromes, namely a deficiency pattern (DP) and an excess pattern (EP), depending on the patient's clinical symptoms, pulse, and lingual signs. Brain functional neuroimaging has demonstrated cerebral activity abnormalities in MD patients. However, such abnormalities have not been linked to particular symptoms of MD. The objective of this work was to compare functional connectivity of the posterior cingulate cortex (PCC) across MD patients with DP, MD patients with EP, and normal control (NC) subjects in a resting-state functional magnetic resonance imaging (rs-fMRI) study. METHODS: Participants (24 DP patients, 21 EP patients, and 20 NCs) underwent rs-fMRI scans. Whole-brain functional connectivity of a seed in the PCC was then mapped for each subject. Functional connectivity differences among the three studied groups were analyzed statistically. RESULTS: Compared to the NC group, DP patients had decreased functional connectivity of the PCC with the right middle temporal gyrus and bilateral precuneus, as well as increased functional connectivity of the PCC with the bilateral middle frontal gyrus. Meanwhile, compared to the NC group, the EP group had decreased functional connectivity of the PCC with both the middle temporal gyrus and bilateral precuneus, as well as increased functional connectivity of the PCC with the bilateral superior frontal gyrus. Relative to the DP group, the EP group had reduced functional connectivity of the PCC with the bilateral cerebellum and left superior frontal gyrus. CONCLUSION: Functional connectivity changes differ between MD patients with different TCM syndrome types, suggesting that the TCM clinical syndromes of MD are associated with correlates in cerebral functional activity.

Combining automatic tube current modulation with adaptive statistical iterative reconstruction for low-dose chest CT screening.

OBJECTIVE: To reduce radiation dose while maintaining image quality in low-dose chest computed tomography (CT) by combining adaptive statistical iterative reconstruction (ASIR) and automatic tube current modulation (ATCM). METHODS: Patients undergoing cancer screening (n = 200) were subjected to 64-slice multidetector chest CT scanning with ASIR and ATCM. Patients were divided into groups 1, 2, 3, and 4 (n = 50 each), with a noise index (NI) of 15, 20, 30, and 40, respectively. Each image set was reconstructed with 4 ASIR levels (0% ASIR, 30% ASIR, 50% ASIR, and 80% ASIR) in each group. Two radiologists assessed subjective image noise, image artifacts, and visibility of the anatomical structures. Objective image noise and signal-to-noise ratio (SNR) were measured, and effective dose (ED) was recorded. RESULTS: Increased NI was associated with increased subjective and objective image noise results (P<0.001), and SNR decreased with increasing NI (P<0.001). These values improved with increased ASIR levels (P<0.001). Images from all 4 groups were clinically diagnosable. Images with NI = 30 and 50% ASIR had average subjective image noise scores and nearly average anatomical structure visibility scores, with a mean objective image noise of 23.42 HU. The EDs for groups 1, 2, 3 and 4 were 2.79 ± 1.17, 1.69 ± 0.59, 0.74 ± 0.29, and 0.37 ± 0.22 mSv, respectively. Compared to group 1 (NI = 15), the ED reductions were 39.43%, 73.48%, and 86.74% for groups 2, 3, and 4, respectively. CONCLUSIONS: Using NI = 30 with 50% ASIR in the chest CT protocol, we obtained average or above-average image quality but a reduced ED.

Hashimoto encephalopathy: a case report with proton MR spectroscopic findings.

A 52-year-old female patient with Hashimoto encephalopathy was admitted to hospital for clinical treatment, and the findings on MR spectroscopy (MRS) and MR imaging (MRI) in the brain were reported. MRS revealed the decreases in N-acetylaspartate (NAA/Cr=1.19) and myo-inositol peaks, and the elevations in lipid, lactate, glutamate/glutamine multiplet and choline (Cho/Cr=1.21) peaks which supported a cerebral inflammatory change, in addition to multifocal hyperintensities on T2WI and fluid-attenuated inversion recovery (FLAIR) images, slight hyperintensities on diffusion weighted imaging (DWI), hypointensities on T1WI. The atrophy of the brain was revealed on follow-up MRI two years later.

Magnetic resonance imaging of eosinophilic meningoencephalitis caused by Angiostrongylus cantonensis following eating freshwater snails.

BACKGROUND: Angiostrongyliasis cantonensis is a worldwide-existing parasitic disease. However, the relevant reports on its radiological appearances are limited. In this study, we investigated magnetic resonance imaging (MRI) features of eosinophilic meningoencephalitis in a group of consecutive patients caused by human infection with Angiostrongylus cantonensis after eating freshwater snails. METHODS: We performed brain MR imaging on 74 patients with angiostrongyliasis cantonensis. The scanner was a 0.5T unit. For each patient MR pulse sequences of SE T1-weighted image (T1WI) and FSE T2-weighted image (T2WI) were used. After intravenous administration of gadolinium chelate (Gd-DTPA) repeated T1-weighted images were obtained. MRI features of the lesions in the brain and meninges were analyzed and recorded after observing initial and follow-up MR images. The classification of the types of angiostrongyliasis cantonensis infection was done on the basis of locations of the disorders. RESULTS: Forty-one (55%) normal and 33 (45%) abnormal MRI appearances in the brain were found. According to locations of the disorders, the types of angiostrongyliasis cantonensis infection were determined as follows: seventeen cases of type meningitis, three of type myeloencephalitis, one of type neuritis and twelve of mixed type (eight of type ventriculitis and five of type pneumonitis were among them). In type meningitis, abnormal leptomeningeal enhancement was visualized. In type myeloencephalitis, lesions in the brain parenchyma may have iso- or slightly low signal intensity on T1WI and high signal intensity on T2WI. Enhanced nodules in various shapes were shown on gadolinium-enhanced T1WI, a few lesions appeared as crescent enhancements and some lesions did not reveal abnormal enhancement. Other than brain lesions, an enhanced nodule was seen in the cervical spinal cord in one patient. In type ventriculitis, brain ventricular enlargement was demonstrated. In type neuritis, a nodule and abnormal enhancement in the right optic nerve was revealed. In type pneumonitis, patchy ground-glass opacity and consolidative lesions at the periphery of the lungs were seen. Follow-up results indicated that most lesions in the brain could resolve in 2 to 8 weeks. CONCLUSIONS: Angiostrongyliasis cantonensis presented as both single type and mixed type. Nodular enhancing lesions in the brain and/or linear enhancement in the leptomeninges were the main findings, while crescent enhancement would be the characteristic sign of the disease on gadolinium-enhanced T1WI. Focal edematous changes without contrast enhancement in the brain could be seen on MRI in some cases.