Objective To observe nasal resistance in healthy adult people and patients with obstructive sleep apnea hypopnea syndrome (OSAHS), comparing the changes in nasal resistance after nCPAP treatment, and to explore the role of nasal resistance in development of OSAHS and the effect of nCPAP on nasal resistance. Methods Detection of nasal resistance was performed in 11 healthy people and 40 patients with OSAHS after completion of polysomnography (PSG). Three weeks after treatment with nCPAP, the patients received polysomnography and detection of nasal resistance again. Results Nasal resistance was higher in patients with OSAHS than healthy people [(0.27 ± 0.9)Pa/(cm3·s) vs. (0.21 ± 0.7)Pa/(cm3·s), t=-2.048, and P<0.05];nasal resistance was not related with age, BMI, neck circumference, waistline, AHI, MinSO2, and ODI (P>0.05). MinSO2, AHI and ODI were markedly improved three weeks after nCPAP therapy (P<0.05). Nasal resistance was increased from (0.27 ± 0.1) Pa/(cm3·s) to (0.43 ± 0.3)Pa/(cm3·s) after treatment (t = -2.733, P < 0.05). Conclusions Increased nasal resistance is one of risk factors for pathogenesis of OSAHS. Nasal resistance is not related with the severity of OSAHS. nCPAP can lead to an elevation in nasal resistance.

Objective To investigate the curative effect of low-temperature plasma-assisted uvulopalatopharyngoplasty(UP-PP)in the patients with positional and non-positional obstructive sleep apnea-hypopnea syndrome(OSAHS).Methods Twenty-six patients with OSAHS diagnosed by polysomnography monitoring receiving the low-temperature plasma-assisted UPPP in our hospital from January 2014 to December 2015 were selected and divided into the positional OSAHS group(PPs) and non-positional OSAHS group(NPPs) according to the apnea-hypopnea index (AHI) under different sleep positional status.The AHI change before and after operation and operation effective rate were compared between the two groups.Results Theoverall AHI,supine position AHI and lateral position AHI in the PPs group all were lower than those in the NPPs group(P＜0.05),moreover the blood oxygen related indexes were higher than those in the NPPs group(P＜0.05).The overall surgical effective rate in the OSAHS patients was 73.08％ (19/26),in which the surgical effective rate was 100％ (7/7) in the PPs group and 63.16％ (12/19) in the NPPs group,the difference between the two groups had no statistical significance(P=0.13).The postoperative total AHI,supine position AHI and lateral position AHI in the two groups were decreased compared with before operation(P＜0.05);the decrease range of lateral position AHI in the NPPs group was significantly higher than that in the supine position AHI[0.96(0.86,1.00)vs.0.53(0.34,0.77),P＜0.01].78.95 ％ (15/19) postoperation patients in the NPPs group converted to PPs.Conclusion Low-temperature plasma-assisted UPPP has some effects on OSAHS patients,in which the benefit of NPPs are more apparent.

Objective To investigate the feasibility of a novel molecular probe 99Tcm-3P4-RGD2 in evaluating arterial plaque stability after atorvastatin intervention in rabbits with SPECT/CT. Methods Eighteen male New Zealand rabbits were randomly divided into group A (stable plaque), group B (vulnerable plaque), and group C (vulnerable plaque with statin intervention). All rabbits were fed with high-fat food for 12 weeks. After high-fat feeding for two weeks, sham surgery was performed on group A. In the meantime, abdominal aorta injury was performed on group B and group C. After that, rabbits of group C were given oral atorvastatin (2.5 mg·kg-1·d-1). 99Tcm-3P4-RGD2 SPECT/CT imaging was performed on each group at the end of 4, 8 and 12 weeks. T/NT ratios were calculated. Animals were sacrificed at the end of 12 week after imaging studies. The abdominal aortas were collected, imaged with SPECT/CT, and evaluated by pathological HE staining and immunohistochemical analysis. MVD was calculated. Differences among 3 groups were analyzed using one-way analysis of variance. Results There was no significant radioactive uptake in the abdominal aortas of three groups on the 4th week′s imaging. The radioactive uptake in abdominal aortas increased slightly on the 8th week, with the highest radioactive uptake in group B. The radioactivity in abdominal aortas of the 3 groups maintained increasing on the 12th week, with T/NT ratios of 1.579±0.217, 1.873±0.226 and 1.524±0.237, respectively (F=8.984, P<0.05). In ex vivo abdominal aorta images, especially images of group B, radioactivity in lesion sites was higher than that in normal tissue. Accordingly, results of HE staining showed that artery plaques of group A and group C were grade Ⅱ and group B was grade Ⅳ. The MVD of group A, B and C was 8.17±1.17, 15.86±1.07 and 7.17±1.60, respectively (F=9036, P<0.05). Conclusion 99Tcm-3P4-RGD2 SPECT/CT imaging has a high sensitivity in the evaluation of arterial plaque stability after statin intervention in rabbits.

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.

Objective: To investigate the feasibility of cine three-dimensional (3D) balanced steady-state free precession (b-SSFP) imaging combined with a non-local means (NLM) algorithm for image denoising in evaluating cardiac function in children with repaired tetralogy of Fallot (rTOF). Materials and Methods: Thirty-five patients with rTOF (mean age, 12 years; range, 7–18 years) were enrolled to undergo cardiac cine image acquisition, including two-dimensional (2D) b-SSFP, 3D b-SSFP, and 3D b-SSFP combined with NLM. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) of the two ventricles were measured and indexed by body surface index. Acquisition time and image quality were recorded and compared among the three imaging sequences. Results: 3D b-SSFP with denoising vs. 2D b-SSFP had high correlation coefficients for EDV, ESV, SV, and EF of the left (0.959– 0.991; p < 0.001) as well as right (0.755–0.965; p < 0.001) ventricular metrics. The image acquisition time ± standard deviation (SD) was 25.1 ± 2.4 seconds for 3D b-SSFP compared with 277.6 ± 0.7 seconds for 2D b-SSFP, indicating a significantly shorter time with the 3D than the 2D sequence (p < 0.001). Image quality score was better with 3D b-SSFP combined with denoising than with 3D b-SSFP (mean ± SD, 3.8 ± 0.6 vs. 3.5 ± 0.6; p = 0.005). Signal-to-noise ratios for blood and myocardium as well as contrast between blood and myocardium were higher for 3D b-SSFP combined with denoising than for 3D b-SSFP (p < 0.05 for all but septal myocardium). Conclusion The 3D b-SSFP sequence can significantly reduce acquisition time compared to the 2D b-SSFP sequence for cine imaging in the evaluation of ventricular function in children with rTOF, and its quality can be further improved by combining it with an NLM denoising method.

OBJECTIVETo investigate the changes in orbitofrontal cortex (OFC) functional connectivity and its association with decision-making deficits in chronic heroin-dependent individuals (HDIs) and explore the neural mechanisms of heroin addiction and relapse.

METHODSFourteen male chronic HDIs and 14 healthy subjects matched for age, education, and nicotine consumption participated in this study. Resting state functional magnetic resonance imaging (fMRI) was performed using a 1.5 T MR scanner. Functional connectivity of the OFC and the rest of the brain were calculated using REST software. Voxel-based analysis of the functional connectivity maps between the control and HDI groups was performed with two-sample t test. The Iowa gambling task (IGT) was used to assess the participants' decision making during uncertainty.

RESULTSCompared with the control group, the HDIs showed significantly decreased functional connectivity of the OFC and the right inferior parietal lobule (rIPL) (t=3.5, P<0.05). A significant negative correlation was noted between the functional connectivity of the OFC-rIPL and performance level at the IGT.

CONCLUSIONThe OFC-rIPL functional connectivity is significantly disrupted in HDIs, which may be the neural basis for decision-making deficits.

Adult ; Case-Control Studies ; Decision Making ; Frontal Lobe ; physiopathology ; Heroin Dependence ; physiopathology ; psychology ; Humans ; Magnetic Resonance Imaging ; Male

Objective To evaluate 18F-fluorodeoxyglucose (FDG) PET/CT in the rabbit model of vulnerable plaques by correlation with 99Tcm-Arg-Gly-Asp (RGD) SPECT/CT imaging,lipid levels,pathological and immunohistochemical results.Methods Sixteen male New Zealand white rabbits were randomly divided into normal diet group (group A,n =4),stable plaque group (group B,n =4) and vulnerable plaque group (group C,n =8) using completely random grouping method.The animals were given abdominal aorta sham operation (groups A and B) or balloon injury of the abdominal aorta (group C) 2 weeks after feeding.Animals were injected with 18F-FDG and 99Tcm-RGD respectively at the end of 4,8 and 12 weeks.PET/CT was performed at 1,2 and 3 h post-injection.SPECT/CT was performed at 30 min post-injection.One rabbit was sacrificed at the end of 4 and 8 weeks after imaging studies,respectively.The others were sacrificed at the end of 12 weeks after imaging studies.All abdominal aortas were harvested.Pathology and immunohistochemistry analysis were performed.The data were analyzed by one-way analysis of variance and Pearson correlation analysis.Results There was no uptake in any group at 4th week and no uptake in group A or group B at 8th week.There was mild uptake in group B at 12th week and group C at 8th week.There was intense uptake in group C at 12th week,whereas both mean standardized uptake value (SUVmean) and maximum standardized uptake value (SUVmax) were significantly higher than the other two groups (F values:7.952,14.279,both P＜0.05).In group C,SUVmax(0.43±0.08,0.68±0.06,1.74±0.63) and SUV (0.37±0.03,0.56±0.03,1.26+0.23) had significant difference at 3 h post-injection for imaging at 4th,8th and 12th week (F values:10.939,39.747,both P＜0.05).At 12th week,there was a strong correlation between the uptake of 18 F-FDG and target/non-target (T/NT) ratio of 99Tcm-RGD in all groups(r values:0.748,0.709,both P＜0.05).Histopathology results showed that the plaques had rich macrophages and a small amount of smooth muscle cells in group C,little macrophages in group B,while no macrophages in group A.Conclusion 18F-FDG PET/CT might be an effective noninvasive method for early assessment of aortic vulnerability to atherosclerotic plaque.

Objective To investigate the value of pulmonary ventilation/ perfusion (V/ Q) SPECT in evaluation of anticoagulant therapy for patients with pulmonary embolism (PE) and identify factors which may affect the therapy. Methods From July 2014 to December 2016, sixty-three patients (23 males, 40 females, age (60±14) years), who were clinically diagnosed as PE and underwent V/ Q SPECT before and after anticoagulant therapy, were recruited retrospectively in this study. According to the percentage of lung perfusion defect (PD) out of total lung volume, the patients were divided into mild (<20％) PE, moderate (20％-50％) PE, and severe (>50％) PE groups. The lung PD decreased≥50％ after anticoagulant thera-py and no new PD detected was defined as the standard of effective therapy, otherwise the treatment were defined as ineffective. Data of different groups were compared. Factors that may predict the severity of PD or affect the treatment were analyzed. χ2 test and logistic regression were used for data analysis. Results PE were detected in 476 pulmonary segments and sub segments. The distribution of PE in different lung lobes had no statistically significant difference ( χ2 = 4. 995, P > 0. 05). More pulmonary arterial hypertension (PAH) were detected in patients with severe PE (80％, 12/ 15) and moderate PE (66.7％,16/ 24) in comparison with patients with mild PE (41.7％,10/ 24; χ2 = 7.062, P<0.05). The occurrence of PAH was related to the severity of PD, with odds ratio (OR) value of 2.680 (95％ CI: 1.115-6.446, P<0. 05).PAH was an independent risk factor for treatment effect (OR value: 3.134(95％ CI: 1.341-7. 324), P<0. 05). Conclusions V/ Q SPECT has an important value for evaluating the effect of anticoagulant therapy and guiding individual therapy. The more extent of PE involved, the higher prevalence of PAH. Anticoagu-lant therapy may be ineffective in PE patients with moderate or severe PAH.