Oxytocin attenuates neuroinflammation-induced anxiety through restoration of excitation and inhibition balance in the anterior cingulate cortex in mice.

BACKGROUND: Accumulative evidence suggested that the oxytocin system plays a role in socio-emotional disorders, although its role in neuroinflammation-induced anxiety remains unclear. METHOD: In the present study, anxiety-like behavior was induced in cohorts of animals through repeated lipopolysaccharide (LPS, 0.5 mg/kg, daily, Escherichia coli O55:B5) i.p. injections for seven consecutive days. These different cohorts were subsequently used for anxiety-like behavior assessment with open field test, elevated plus maze, and novelty-suppressed feeding test or for electrophysiology (EEG) recordings of miniature excitatory postsynaptic currents (mEPSCs), miniature inhibitory postsynaptic currents (mIPSCs), or local field potential (LFP) in vivo or ex vivo settings. Samples of the anterior cingulate cortex (ACC) from some cohorts were harvested to conduct immunostaining or western blotting analysis of oxytocin, oxytocin receptor, CamkII, GABA, vGAT, vGLUT2, and c-fos. The dendritic spine density was assessed by Golgi-Cox staining. RESULTS: Repeated LPS injections induced anxiety-like behavior with concurrent decreases of oxytocin, vGLUT2, mEPSC, dendritic spine, c-fos, membrane excitability, and EEG beta and gamma oscillations, but increased oxytocin receptor and vGAT expressions in the ACC; all these changes were ameliorated by oxytocin intranasal or local brain (via cannula) administration. CONCLUSION: Taken together, our data suggested that oxytocin system may be a therapeutic target for developing treatment to tackle neuroinflammation-induced anxiety.

A long duration of intraoperative hypotension is associated with postoperative delirium occurrence following thoracic and orthopedic surgery in elderly.

BACKGROUND: Postoperative delirium (POD) is a common surgical complication associated with increased morbidity and mortality in elderly. Although the underlying mechanisms remain elusive, perioperative risk factors were reported to be closely related to its development. This study was designed to investigate the association between the duration of intraoperative hypotension and POD incidence following thoracic and orthopedic surgery in elderly. METHOD: The perioperative data from 605 elderly undergoing thoracic and orthopedic surgery from January 2021 to July 2022 were analyzed. The primary exposure was a cumulative duration of mean arterial pressure (MAP) ≤ 65 mmHg. The primary end-point was the POD incidence assessed with confusion assessment method (CAM) or CAM-ICU for three days after surgery. Restricted cubic spline (RCS) was conducted to examine the continuous relationship between the duration of intraoperative hypotension and POD incidence adjusted with patients' demographics and surgery related factors. Then the duration of intraoperative hypotension was categorized into three groups: no hypotension, short (< 5 mins) or long duration (≥ 5 mins) of hypotension for further analysis. RESULT: The incidence of POD was 14.7% (89 cases out of 605) within three days after surgery. The duration of hypotension presented a non-linear and "inverted L-shaped" effect on POD development. Compared to no hypotension, long duration (adjusted OR 3.93; 95% CI: 2.07-7.45; P < 0.001) rather than short duration of MAP ≤65 mmHg (adjusted OR 1.18; 95% CI: 0.56-2.50; P = 0.671) was closely related to the POD incidence. CONCLUSION: Intraoperative hypotension (MAP ≤65 mmHg) for ≥5 mins was associated with an increased incidence of POD after thoracic and orthopedic surgery in elderly.

Extracorporeal membrane oxygenation for coronavirus disease 2019-associated acute respiratory distress syndrome: Report of two cases and review of the literature.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2, is a worldwide pandemic. Some COVID-19 patients develop severe acute respiratory distress syndrome and progress to respiratory failure. In such cases, extracorporeal membrane oxygenation (ECMO) treatment is a necessary life-saving procedure. CASE SUMMARY: Two special COVID-19 cases-one full-term pregnant woman and one elderly (72-year-old) man-were treated by veno-venous (VV)-ECMO in the Second People's Hospital of Zhongshan, Zhongshan City, Guangdong Province, China. Both patients had developed refractory hypoxemia shortly after hospital admission, despite conventional support, and were therefore managed by VV-ECMO. Although both experienced multiple ECMO-related complications on top of the COVID-19 disease, their conditions improved gradually. Both patients were weaned successfully from the ECMO therapy. At the time of writing of this report, the woman has recovered completely and been discharged from hospital to home; the man remains on mechanical ventilation, due to respiratory muscle weakness and suspected lung fibrosis. As ECMO itself is associated with various complications, it is very important to understand and treat these complications to achieve optimal outcome. CONCLUSION: VV-ECMO can provide sufficient gas exchange for COVID-19 patients with acute respiratory distress syndrome. However, it is crucial to understand and treat ECMO-related complications.

CT imaging and pathological basis of linear shadow connecting pulmonary segmental artery to horizontal fissure.

To investigate the computed tomography (CT) imaging and pathological basis of the linear shadows connecting pulmonary segmental arteries to horizontal fissure (hereinafter referred to as "linear shadow") on thin-slice CT.Collect 127 clinical cases to analyze the display and morphology of linear shadows on the thin-slice CT and to measure their length, thickness, and angle. Collect 11 autopsy specimens of coal worker's pneumoconiosis to conduct an imaging and pathology basis control study for the linear shadows.There is no correlation between the linear shadow and gender, age, and smoking history. Linear shadows are observed in 54.33% of patients. 93.33% of those linear shadows are straight lines. Generally, the lengths are less than 10 mm, the thicknesses are around 1 mm, and the scopes of angles are wide, range from acute angles to obtuse angles. The linear shadow is a banded structure consisting of loose connective tissue, small blood vessels, and small lymphatic vessels due to the visceral pleura recessed and fused into the lung.Linear shadows are intrinsic to the lung. The linear shadows consist of loose connective tissue, small blood vessels, and small lymphatic vessels.

Exogenous GM1 Ganglioside Attenuates Ketamine-Induced Neurocognitive Impairment in the Developing Rat Brain.

BACKGROUND: A prolonged exposure to ketamine triggers significant neurodegeneration and long-term neurocognitive deficits in the developing brain. Monosialotetrahexosylganglioside (GM1) can limit the neuronal damage from necrosis and apoptosis in neurodegenerative conditions. We aimed to assess whether GM1 can prevent ketamine-induced developmental neurotoxicity. METHODS: Postnatal day 7 (P7) rat pups received 5 doses of intraperitoneal ketamine (20 mg/kg per dose) at 90-minute intervals for 6 hours. Cognitive functions, determined by using Morris water maze (MWM) including escape latency (at P32-36) and platform crossing (at P37), were compared among the ketamine-exposed pups treated with or without exogenous GM1 (30 mg/kg; n = 12/group). The effect of GM1 on apoptosis in hippocampus was determined by terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling (TUNEL) staining and activated caspase 3 measurement. The hippocampal expression of brain-derived neurotrophic factor (BDNF), along with the phosphorylation of protein kinase B (AKT) and extracellular signal-related kinases 1 and 2 (ERK1/2), was detected by western blotting (n = 6/group). Anti-BDNF antibody (2 µg per rat) administered before GM1 treatment was applied to determine the neuroprotective mechanisms of GM1. RESULTS: The rats receiving ketamine exposure experinced cognitive impairment in MWM test compared to the control rats, indicated by prolonged escape latency at P34 (P = .006), P35 (P = .002), and P36 (P = .005). However, in GM1-pretreated rats, ketamine exposure did not induce prolonged escape latency. The exogenous GM1 increased the platform-crossing times at P37 (3.00 ± 2.22 times vs 5.40 ± 1.53 times, mean ± standard deviation; P = .041) and reduced the hippocampal TUNEL-positive cells and cleaved-caspase 3 expression in ketamine-exposed young rats. Ketamine decreased BDNF expression and phosphorylation of AKT and ERK in the hippocampus, whereas exogenous GM1 blocked these ketamine-caused effects. However, for the ketamine-exposed rat pups receiving exogenous GM1, compared to immunoglobulin Y (IgY) isotype control, the BDNF-neutralizing antibody treatment counteracted the exogenous GM1-induced improvement of the escape latency at P36 (41.32 ± 12.37 seconds vs 25.14 ± 8.97 seconds, mean ± standard deviation; P = .036), platform-crossing times at P37 (2.16 ± 1.12 times vs 3.92 ± 1.97 times, mean ± standard deviation; P < .036), apoptotic activity, as well as AKT and ERK1/2 phosphorylation in the hippocampus of ketamine-challenged young rats. CONCLUSIONS: Our data suggest that the exogenous GM1 acts on BDNF signaling pathway to ameliorate the cognitive impairment and hippocampal apoptosis induced by ketamine in young rats. Our study may indicate a potential use of GM1 in preventing the cognitive deficits induced by ketamine in the young per se.

Linear shadows that connect oblique fissures and costal pleurae on the superior segments of lower lobes: evaluating the imaging findings on thin-slice lung CT.

OBJECTIVE: To retrospectively analyse the imaging findings of the linear shadows that connect the oblique fissures and the costal pleurae on the superior segments of the lower lobes on thin-slice lung CT. MATERIALS AND METHODS: Thin-slice CT scans of 221 cases of normal lungs and 86 abnormal lungs were collected. The parameters of the imaging observations included the existence of the superior segmental linear shadow, its morphology, length, and starting position, bird-beak sign, and adjacent structures on the pleural end. RESULTS: The linear shadows were more common on the left lower lobe (43.44%) than on the right side (19.46%). The pleural origins of the linear shadows were mainly located above the carina (69.78%); the adjacent structure on the left lung was the descending aorta (70.83%), and for the right lung, it was next to the thoracic vertebrae (60.47%). In the presence of pulmonary lobectomy or atelectasis, the linear shadows could be extended, which could pull the oblique fissures and costal pleurae to form the bird-beak sign. CONCLUSION: The linear shadows on the superior segments of the lower lobes are common structures fixing the oblique fissures. Recognition of the linear shadows can help radiologists distinguish normal structures from abnormal ones.

Short linear shadows connecting pulmonary segmental arteries to oblique fissures in volumetric thin-section CT images: comparing CT, micro-CT and histopathology.

OBJECTIVES: To retrospectively evaluate short linear shadows connecting pulmonary segmental arteries to oblique fissures in thin-section CT images and determine their anatomical basis. METHODS: CT scanning was performed on 108 patients and 11 lung specimens with no lung diseases around the oblique fissures or hila. Two radiologists evaluated the imaging. The parameters included length, thickness of short linear shadows, pulmonary segmental artery variations, and traction interlobar fissures, etc. RESULTS: The short linear shadows were not related to sex, age, or smoking history. The lengths of the short linear shadows were generally within 10 mm. The thicknesses of the short linear shadows ranged from 1 to 2 mm. Of the patients, 26.9 % showed pulmonary segmental artery variations; 66.7 % of short linear shadows pulled oblique fissures. In three-dimensional images, the short linear shadows appeared as arc planes, with one side edge connected to the oblique fissure, one side edge connected to a pulmonary segmental artery. On the tissue slices, the short linear shadow exhibited a band structure composed of connective tissues, small blood vessels, and small lymphatic vessels. CONCLUSIONS: Short linear shadows are a type of normal intrapulmonary membranes and can maintain the integrity of the oblique fissures and hilar structure. KEY POINTS: • Volumetric thin-section CT scanning is commonly used to study lung anatomy. • Short linear shadows are a common intrapulmonary structure in thin-section CT. • Short linear shadows correlate with band structures on the correlative tissue slices.

Volumetric thin-section CT: evaluation of pulmonaryinterlobar fissures.

PURPOSE: We aimed to perform an imaging analysis of interlobar fissures and their variations using thin-section computed tomography (CT). METHODS: Volumetric thin-section CT scanning was performed in 208 subjects. Interlobar fissures were observed on axial images, and reconstructed coronal and sagittal images were observed by multiplanar reformatting (MPR). The vessel distributions were verified by maximal intensity projection (MIP). On the axial images, the interlobar fissures were characterized by lines of hyperattenuation, bands of hyperattenuation, avascular zones, and mixed imaging. The interlobar fissures were divided into seven grades according to the percentage of defects over the entire fissure. RESULTS: On the axial images, of all interlobar fissures without avascular zones, 70.2% of the right oblique fissures (ROFs) and 94.2% of the left oblique fissures (LOFs) appeared as lines, and 83.2% of the horizontal fissures (HFs) appeared as bands. All of the interlobar fissures appeared as lines on the coronal and sagittal images. Of all cases, 17.8% showed fully complete interlobar fissures for all three fissures. Incomplete fissures included 41.3% of ROFs, 58.2% of HFs, and 45.2% of LOFs. In ROFs and LOFs, discontinuity was most frequently below 20%, while in HFs discontinuity was most frequently 41%-60%. The most common classification of incomplete interlobar fissures was a discontinuous avascular zone. CONCLUSION: Incomplete interlobar fissures are common variations of interlobar fissures. Techniques including volumetric thin-section CT, MPR, and MIP can assist in the diagnosis of incomplete interlobar fissures.

Goal-directed Fluid Therapy May Improve Hemodynamic Stability of Parturient with Hypertensive Disorders of Pregnancy Under Combined Spinal Epidural Anesthesia for Cesarean Delivery and the Well-being of Newborns.

BACKGROUND: Hypotension induced by combined spinal epidural anesthesia in parturient with hypertensive disorders of pregnancy (HDP) can easily compromise blood supply to vital organs including uteroplacental perfusion and result in fetal distress. The aim of this study was to investigate whether the goal-directed fluid therapy (GDFT) with LiDCO rapid system can improve well-being of both HDP parturient and their babies. METHODS: Fifty-two stable HDP parturient scheduled for elective cesarean delivery were recruited. After loading with 10 ml/kg lactated Ringer's solution (LR), parturient were randomized to the GDFT and control group. In the GDFT group, individualized fluid therapy was guided by increase in stroke volume (ΔSV) provided via LiDCO rapid system. The control group received the routine fluid therapy. The primary endpoints included maternal hypotension and the doses of vasopressors administered prior to fetal delivery. The secondary endpoints included umbilical blood gas abnormalities and neonatal adverse events. RESULTS: The severity of HDP was similar between two groups. The total LR infusion (P < 0.01) and urine output (P < 0.05) were higher in the GDFT group than in the control group. Following twice fluid challenge tests, the systolic blood pressure, mean blood pressure, cardiac output and SV in the GDFT group were significantly higher, and the heart rate was lower than in the control group. The incidence of maternal hypotension and doses of phenylephrine used prior to fetal delivery were significantly higher in the control group than in the GDFT group (P < 0.01). There were no differences in the Apgar scores between two groups. In the control group, the mean values of pH in umbilical artery/vein were remarkably decreased (P < 0.05), and the incidences of neonatal hypercapnia and hypoxemia were statistically increased (P < 0.05) than in the GDFT group. CONCLUSIONS: Dynamic responsiveness guided fluid therapy with the LiDCO rapid system may provide potential benefits to stable HDP parturient and their babies.

A Giant Gastric Adenoma Embedded in the Duodenum.

Gastric adenomas are usually located in the antrum, or occasionally in the fundus of the stomach. Most adenomas are solitary, pedunculated mass. The report describes a 17-year girl who visited the emergency room with complaints of stabbing pain of upper abdomen, nausea, vomiting and melena for last one week. Emergency endoscopic examination revealed a giant polyp with a long about 15 cm pedicle embedded in the duodenum. The polyp was completely removed by surgery, about 15 x 3 x 4 cm in size. At 5-year follow-up by endoscopy and ultrasonography, the patient remained in good general condition. It emphasizes that giant gastric adenomas must be removed by endoscopy or surgery due to its potential of malignancy. It is necessary to follow-up for detecting early gastric neoplasm.

AIDS-related non-Hodgkin lymphoma: imaging feature analysis of 27 cases and correlation with pathologic findings.

BACKGROUND: Some tumor types are related to HIV, including non-Hodgkin lymphoma (NHL). The morbidity and mortality of NHL has remained high, even after highly active antiretroviral therapy (HAART) was introduced. We collected cases of AIDS with NHL, and evaluated the imaging features and strategies for diagnosis. MATERIALS AND METHODS: There were 27 patients with AIDS and tumors confirmed by pathology. There were 9 patients with Burkitt lymphoma, 16 with diffuse large B cell lymphomas (DLBCLs), and 2 with primary central nervous system (PCNS) lymphomas. All of the patients underwent a series of imaging studies. Three radiologists analyzed the images, and any disagreement was discussed until consensus was reached. RESULTS: The radiologic manifestations of AIDS with NHL were mainly masses and lymphadenopathy, 3 patients having one mass and 12 two or more masses. 7 patients had lymphadenopathy in one site and 3patients had lymphadenopathy in two or more sites. Coarse mucosal folds, thickening of the gastrointestinal wall, and lumen narrowing were typical manifestations of NHL within the gastrointestinal tract. There were 4 patients with masses and 5 with lymphadenopathy inthe 9 with Burkitt lymphoma, and 11 patients with masses 5 with lymphadenopathy in the 16 with DLBCLs. CONCLUSION: NHL is a malignancy that usually occurs in patients with AIDS. Imaging is an important method by which to evaluate lesions, masses, and lymphadenopathy. Fine needle aspiration biopsy and stereotaxis biopsy are useful methods by which to diagnose NHL.

Cardiovascular parameters to assess the severity of acute pulmonary embolism with computed tomography.

BACKGROUND: Computed tomographic pulmonary angiography (CTPA) has been established as a first-line test in the acute pulmonary embolism (APE) diagnostic algorithm, but the assessment of the severity of APE by this method remains to be explored. PURPOSE: To retrospectively evaluate right ventricular (RV) dysfunction and severity in patients with APE without underlying cardiopulmonary disease using helical computed tomography (CT). MATERIAL AND METHODS: Seventy-three patients (35 men and 38 women) were divided into two groups according to the clinical findings: severe APE (n=22) and non-severe APE (n=51). Pulmonary artery CT obstruction index was calculated according to the location and degree of clots in the pulmonary arteries. Cardiovascular parameters including RV short axis and left ventricular (LV) short axis, RV short axis to LV short axis (RV/LV) ratio, main pulmonary artery, azygos vein, and superior vena cava diameters were measured. Leftward bowing of the interventricular septum, reflux of contrast medium into the inferior vena cava and azygos vein, and bronchial artery dilatation were also recorded. The results were analyzed by Mann-Whitney U test, chi(2) test, Spearman's rank correlation coefficient, and the area under the receiver operating characteristic curve (A(z)). RESULTS: CT obstruction index in patients with severe APE (median 43%) was higher than that of patients with non-severe APE (median 20%). Comparison of cardiovascular parameters between patients with severe and non-severe pulmonary embolism showed significant differences in RV short axis, LV short axis, RV/LV ratio, RV wall thickness, main pulmonary artery diameter, azygos vein diameter, leftward bowing of the interventricular septum, and bronchial artery dilatation. The correlation between CT obstruction indexes and cardiovascular parameters was significant. Spearman's rank correlation coefficient was highest between RV/LV ratio and CT obstruction index. A(z) values were significantly higher than 0.5 for CT obstruction index, LV short axis, RV/LV ratio, main pulmonary artery diameter, and azygos vein diameter. CONCLUSION: These results suggest that CTPA is a practical and accurate means for evaluating RV dysfunction of pulmonary embolism in patients without any underlying cardiopulmonary disease and can discriminate between severe and non-severe APE.

Comparison of different diagnostic methods for differentiating biliary atresia from idiopathic neonatal hepatitis.

AIM: To retrospectively analyze different methods in differentiating biliary atresia from idiopathic neonatal hepatitis. METHODS: Sixty-nine infants with cholestatic jaundice and final diagnosis of idiopathic neonatal hepatitis (INH) and biliary atresia (BA) were studied retroprospectively from January 2004 to December 2006. A thorough history and physical examination were undertaken. All cases underwent abdominal magnetic resonance cholangiography (MRCP), ultrasonography (US), hepatobiliary scintigraphy (HBS), HBS single-photon emission computer tomography (HBS SPECT), and operation or percutaneous liver biopsy. The accuracy, sensitivity, specificity, and predictive values of these various methods were compared. RESULTS: There were 39 girls and 30 boys, among whom 35 had INH (age, 61+/-17 days) and 34 had BA (age, 64+/-18 days). The mean age at onset of jaundice was significantly lower in cases of BA when compared to INH cases (9+/-13 vs. 20+/-21 days; P=.032). The diagnostic accuracy of different methods was as follows: liver biopsy, 97.1%; HBS SPECT, 91.30%; MRCP, 71.01%; HBS, 66.67%; US, 65.22%. CONCLUSION: Our results indicate that biopsy of the liver is considered as the most reliable method to differentiate INH from BA. The accuracy of HBS SPECT is higher than that of MRCP, HBS, and US. There was no significant difference in diagnostic accuracy among MRCP, HBS, and US.

Value of multiplanar reconstruction in MSCT in demonstrating the relationship between solitary pulmonary nodule and bronchus.

In this report, we studied the value of the solitary pulmonary nodule (SPN)-bronchus relationship in determining the nature of SPN by multiplanar reconstruction (MPR) in multislice spiral computed tomography (MSCT). One hundred forty-eight SPN cases were enrolled. CT was performed in all cases using MSCT. Images were then transferred to a processing workstation for MPR. The results showed that MPR is a valuable tool for visualizing the SPN-bronchus relationship and that the SPN-bronchus relationship is useful in determining the nature and the degree of differentiation of SPN.

Computed tomography perfusion in evaluating the therapeutic effect of transarterial chemoembolization for hepatocellular carcinoma.

AIM: To prospectively assess the changes in parameters of computed tomography (CT) perfusion pre- and post-transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) in different treatment response groups, and to correlate the changes with various responses of HCC to TACE. METHODS: Thirty-nine HCC patients underwent CT perfusion examinations pre-(1 d before TACE) and post-treatment (4 wk after TACE). The response evaluation criteria for solid tumors (RECIST) were referred to when treatment responses were distributed. Wilcoxon-signed ranks test was used to compare the differences in CT perfusion parameters pre- and post-TACE for different response groups. RESULTS: Only one case had treatment response to CR and the CT perfusion maps of post-treatment lesion displayed complete absence of signals. In the PR treatment response group, hepatic artery perfusion (HAP), hepatic arterial fracture (HAF) and hepatic blood volume (HBV) of viable tumors post-TACE were reduced compared with pre-TACE (P = 0.001, 0.030 and 0.001, respectively). In the SD group, all CT perfusion parameters were not significantly different pre- and post-TACE. In the PD group, HAP, HAF, portal vein perfusion (PVP) and hepatic blood flow (HBF) of viable tumors post-TACE were significantly increased compared with pre-TACE (P = 0.005, 0.012, 0.035 and 0.005, respectively). CONCLUSION: Changes in CT perfusion parameters of viable tumors are correlated with different responses of HCC to TACE. Therefore, CT perfusion imaging is a feasible technique for monitoring response of HCC to TACE.

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.

Neural network-based computer-aided diagnosis in distinguishing malignant from benign solitary pulmonary nodules by computed tomography.

BACKGROUND: Computer-aided diagnosis (CAD) of lung cancer is the subject of many current researches. Statistical methods and artificial neural networks have been applied to more quantitatively characterize solitary pulmonary nodules (SPNs). In this study, we developed a CAD scheme based on an artificial neural network to distinguish malignant from benign SPNs on thin-section computed tomography (CT) images, and investigated how the CAD scheme can help radiologists with different levels of experience make diagnostic decisions. METHODS: Two hundred thin-section CT images of SPNs with proven diagnoses (135 small peripheral lung cancers and 65 benign nodules) were analyzed. Three clinical features and nine CT signs of each case were studied by radiologists, and the indices of qualitative diagnosis were quantified. One hundred and forty nodules were selected randomly to form training samples, on which the neural network model was built. The remaining 60 nodules, forming test samples, were presented to 9 radiologists with 3 - 20 years of clinical experience, accompanied by standard reference images. The radiologists were asked to determine whether a nodule was malignant or benign first without and then with CAD output. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis. RESULTS: CAD outputs on test samples had higher agreement with pathological diagnoses (Kappa = 0.841, P < 0.001). Compared with diagnostic results without CAD output, the average area under the ROC curve with CAD output was 0.96 (P < 0.001) for junior radiologists, 0.94 (P = 0.014) for secondary radiologists and 0.96 (P = 0.221) for senior radiologists, respectively. The differences in diagnostic performance with CAD output among the three levels of radiologists were not statistically significant (P = 0.584, 0.920 and 0.707, respectively). CONCLUSIONS: This CAD scheme based on an artificial neural network could improve diagnostic performance and assist radiologists in distinguishing malignant from benign SPNs on thin-section CT images.