Heart sound classification using energy distribution features extracted with wavelet packet decomposition / 中国医学物理学杂志

Objective To propose a distribution feature extraction algorithm based on wavelet packet coefficients to reconstruct the signal energy sequence for effectively identifying the pathological features of heart sounds,thereby realizing the early screening of heart diseases.Methods The original heart sound signal was decomposed into 10 layers using wavelet packet decomposition algorithm.After obtaining the wavelet packet coefficients of each layer,each coefficient was reconstructed,and the energy of the reconstructed signal was calculated and arranged in the original order to form the energy sequence.The distribution characteristics of the energy sequence of the reconstructed signals at each layer were analyzed,and distribution features were taken as classification features.Support vector machine,K-nearest neighbor,and decision tree were used to classify and recognize normal heart sounds and the heart sound signals of various diseases.Results The combination of the distribution features of the reconstructed signal energy sequence and decision tree classifier had an accuracy of 93.6%for classifying 5 types of heart sounds on the public dataset,and the accuracy was 95.6%for identifying normal heart sounds and hypertrophic cardiomyopathy heart sounds.Conclusion The proposed algorithm can extract the effective pathological information of abnormal heart sounds,providing a reference for clinical cardiac auscultation.

Prediction of recurrence risk of estrogen receptor-positive and human epidermal growth factor receptor-2 negative breast cancer using a multi-parameter regression model based on diffusion kurtosis imaging / 中华放射学杂志

Objective:To explore the predictive value of a regression model based on diffusion kurtosis imaging (DKI) parameters for prediction of the recurrence risk in patients with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER-2)-negative early invasive breast cancer.Methods:A retrospective cross-sectional study was designed. The clinicopathological (age, histological grade, Ki-67 level, etc.) and imaging data of 50 patients (50 lesions) with ER-positive, HER-2 negative early invasive breast cancer who underwent treatment at Wuxi People′s Hospital from January 2016 to December 2018 were retrospectively analyzed. All patients were female, aged 29 to 81 years, and underwent pre-operation conventional MRI and DKI examinations. The volume of breast fibroglandular tissue (FGT), background parenchymal enhancement (BPE), and internal enhancement features were recorded; the peak enhancement (PH), peak enhancement rate, time to peak, mean kurtosis (MK), and mean diffusivity (MD) were calculated. Based on the 21-gene recurrence risk scores, patients were divided into low recurrence risk group and medium-high recurrence risk group. Independent sample t test, Mann-Whitney U test, χ2 test were used to compare the differences of various indicators between the two groups. Two logistic models were constructed with age, PH, MD, and MK as independent variables (Pre1), and with Ki-67, age, PH, MD, and MK as independent variables (Pre2), respectively. The efficacy of the models in predicting low recurrence risk in patients was assessed using receiver operating characteristic curve and area under the curve (AUC). Results:There were 25 cases in the low recurrence risk group and 25 cases in the medium-high recurrence risk group. The differences in age, FGT, PH, MD, MK, and Ki-67 between the low recurrence risk group and the medium-high recurrence risk group were statistically significant (all P<0.05), while other indexes showed no statistically significant differences (all P>0.05). The AUC of Pre1 in predicting low recurrence risk of ER-positive, HER-2 negative early invasive breast cancer was 0.87, with a sensitivity of 0.76 and specificity of 0.88. The AUC of Pre2 for predicting the low recurrence risk of ER-positive, HER-2 negative early invasive breast cancer was 0.92, with a sensitivity of 0.84, and specificity of 0.92. Conclusions:A multi-parameter model based on DKI can effectively predict the recurrence risk of ER-positive and HER-2 negative breast cancer. The model with combination of Ki-67 can further improve the predictive efficacy, and help effectively identify patients at low recurrence risk.

Brain white matter variation in patients with obstructive sleep apnea-hypopnea syndrome with diffusional kurtosis imaging / 中国耳鼻咽喉头颈外科

OBJECTIVE To explore the changes of brain white matter of the patients with obstructive sleep apnea-hypopnea syndrome(OSAHS)with magnetic resonance diffusional kurtosis imaing(DKI).METHODS There were 38 patients with OSAHS examined by polysomnogram(PSG)from November 2017 to June 2021,and 32 non-OSAHS controls matched in gender and age who were included in this study.All the subjects were scanned by DKI.The different encephalic regions through comparing kurtosis fractional anisotropy(KFA)values of all encephalic regions between the two groups were found,and the relationship between the KFA values of the different encephalic regions in OSAHS patients and the apnea-hypopnea index(AHI),lowest saturation oxygen(LSaO2)and the percent of the total record time spent below 90%oxygen saturation(TS90%)in PSG were analyzed.RESULTS The KFA values of white matter fiber tracts in corpus callosum,bilateral corona radiata,cingulate gyrus,right superior cerebellar peduncle and inferior cerebellar peduncle of OSAHS group were obviously lower than control group(P<0.05).After controlling for age and body mass index(BMI),the partial correlation between AHI and the KFA values of corpus callosum,left posterior corona radiata,right anterior corona radiata,cingulate gyrus in OSAHS group were also negative(r=-0.344,-0.380,-0.406,-0.53,P<0.05).The partial correlation between LSaO2 and the KFA values of corpus callosum,left posterior corona radiata,right anterior corona radiata,cingulate gyrus,right superior cerebellar peduncle in OSAHS group were also positive(r=0.366,0.406,0.446,0.404,0.342,P<0.05).The partial correlation between TS90%and the KFA values of corpus callosum,left posterior corona radiata,right anterior corona radiata,cingulate gyrus,right superior cerebellar peduncle and inferior cerebellar peduncle in OSAHS group were also negative(r=-0.414,-0.352,-0.355,-0.336,-0.456,-0.360,P<0.05).CONCLUSION Recurrent apnea and hypoxemia at night of OSAHS patients can cause damage to white matter fibers in parts of encephalic regions.

Abnormal changes of white matter structure in temporal lobe epilepsy patients with sleep disorders based on diffusion kurtosis imaging / 实用放射学杂志

Objective To investigate the microstructural changes of temporal lobe epilepsy(TLE)in patients with sleep disorders based on diffusion kurtosis imaging(DKI).Methods This research prospectively included 38 TLE patients(case group)and 20 healthy controls(HC)(HC group).Participants used sleep questionnaires to evaluate their sleep status.All TLE patients were divided into groups with and without sleep disorders according to the diagnostic criteria and scale scores of sleep disorders.The mean kurtosis(MK),mean diffusivity(MD),and fractional anisotropy(FA)of the relevant region of interest(ROI)were measured by DKI sequence.The differences of sleep quality scores and DKI parameters between groups were further compared via independent samples t-test and one-way analysis of variance.Results The Epworth sleepiness scale(ESS),Athens insomnia scale(AIS),and Pittsburgh sleep qual-ity index(PSQI)scores of TLE patients with sleep disorders were significantly higher than those of HC group(P＜0.05).The FA and MK values in TLE patients were significantly lower than those in HC group,while the MD value of TLE patients were substan-tially higher than that of HC group(P＜0.05).The values of MK and FA in left TLE patients with sleep disorders were significantly lower than those of without sleep disorders(P＜0.05),while there was no significant difference in MD value between the two groups(P＞0.05).MK value of right TLE patients with sleep disor-ders was significantly lower than that of without sleep disorders(P＜0.05),however,there were no significant differences in MD and FA values between the two groups(P＞0.05).Conclusion Quantitative DKI analysis revealed differences in DKI parameters in TLE patients combined with sleep disorders,inferring a specific white matter fiber damage in this group and providing imaging data to support the personalized treatment and prognostic assessment of these patients.

Diffusion kurtosis imaging in assessment of structural brain network topology alteration and microstructural damage in patients with multiple sclerosis / 中华放射学杂志

Objective:To investigate the changes in structural brain network topology and microstructural damage in patients with multiple sclerosis (MS), and to analyze its correlation with cognitive function.Methods:Clinical and imaging data of 114 patients with MS (MS group) diagnosed in the First Affiliated Hospital of Chongqing Medical University from May 2021 to September 2022 were analyzed retrospectively. In addition, 71 volunteers were recruited as a healthy control group (HC group) during the same period. All subjects were performed on cognitive assessment and 3D-T 1 magnetization-prepared rapid gradient echo, 3D-fluid-attenuated inversion recovery, and diffusion kurtosis imaging (DKI) scans. GRETNA software was used to obtain network topology attributes, and global attributes included global efficiency, local efficiency, and small-world attributes [clustering coefficient(Cp), shortest path length(Lp), normalized Cp(γ), normalized Lp, and small-world index (σ)]. Local attributes included betweenness centrality (BC), degree centrality (DC), nodal clustering coefficient (NCp), nodal efficiency, nodal local efficiency (NLe) and nodal shortest path length. The DKI parameter map generated by the post-processing software was used to extract the DKI parameter values of the brain region with abnormal local topology of the brain structure network. The differences of global attributes, local attributes and DKI parameter values [kurtosis fractional anisotropy (KFA), mean kurtosis (MK), radial kurtosis (RK) and axial kurtosis (AK) values] were analyzed by independent sample t-test or Mann-Whitney U test, and corrected by false discovery rate (FDR). Spearman or Pearson correlation analysis was used to evaluate the correlation between abnormal brain structure network topology attributes and cognitive scale scores in the MS group. Results:Both the MS group and the HC group structure network showed small-world attributes, and the γ and σ values of the MS group were significantly lower than those in the HC group (FDR correction, P<0.05). Compared with the HC group, BC, DC, NCp and NLe broadly reduced in the MS group, mainly involving in bilateral frontal, temporal, precuneus, amygdala, and thalamus (FDR correction, P<0.05). After FDR correction, compared with the HC group, the KFA, MK, RK and AK values of 23 brain regions with abnormal local attributes of the network in the MS group were significantly changed in several brain regions (FDR correction, P<0.05). The correlation analysis showed, after FDR correction, the DC value of the right putamen in MS patients was positively correlated with the digit span test (DST) scores ( r=0.318 ,P=0.001). Conclusion:There are extensive changes in the structural brain network of MS patients, accompanied by varying degrees of microstructural damage, and the reduction of degree centrality in the basal ganglia putamen region is associated with cognitive impairment.

Prognostic value of diffusion kurtosis imaging histogram based nomogram model for cervical cancer / 中华放射肿瘤学杂志

Objective:To analyze the prognostic value of nomogram model for cervical cancer based on the imaging features of diffusion kurtosis imaging (DKI) histogram.Methods:The DKI and clinical data of 272 patients with cervical cancer who were admitted to Affiliated Hospital of Guangdong Medical University from March 2015 to February 2022 were collected and retrospectively analyzed. All patients were randomly divided into the training group ( n=190) and validation group ( n=82) at a ratio of 7 vs. 3. The parameters of DKI histogram were obtained by GE AW 4.2 MRI software. The best prognostic imaging features were screened by LASSO regression. The DKI radiomics score was calculated by linear combination. The independent risk factors of prognosis were identified by univariate and multivariate regression analyses, and a nomogram model was constructed. The model discrimination was assessed by the area under the receiver operating characteristic (ROC) curve (AUC). The internal consistency of the model was evaluated by the calibration map. Results:Adenocarcinoma ( HR=2.496, 95% CI=1.312-4.749, P=0.005), DKI score ( HR=24.087, 95% CI=6.062-95.711, P<0.001), depth of invasion ≥ 1/2 muscular layer ( HR=2.277, 95% CI=1.156-4.487, P=0.017) and neutrophil to lymphocyte ratio (NLR) ( HR=1.800, 95% CI=1.313-2.468, P<0.001) were the independent risk factors for prognosis of cervical cancer. The AUC of the nomogram model in the training and validation groups were 0.860 and 0.757, respectively. The calibration curve was well fitted with the 45° diagonal. The prediction results of long-term prognosis of this model were in good agreement with the actual situation. Conclusions:Adenocarcinoma, NLR, DKI score and depth of invasion ≥ 1/2 muscular layer are the independent risk factors for the prognosis of patients with cervical cancer. The constructed nomogram model could reliably predict the 3-year survival rate of patients with cervical cancer.

Diagnostic value of diffusion kurtosis imaging quantitative parameters in lymph node metastasis of rectal cancer / 肿瘤研究与临床

Objective:To investigate the diagnostic value of diffusion kurtosis imaging (DKI) quantitative parameters in lymph node metastasis of rectal cancer.Methods:The clinicopathological data of 79 patients with rectal cancers in Shanxi Province Cancer Hospital from November 2016 to March 2017 were retrospectively analyzed. All patients underwent routine magnetic resonance image (MRI) sequence and DKI sequence examinations before the operation. The tumor region of interest (ROI) was delineated by two radiologists. Matlab software was applied to calculate DKI quantitative parameters including apparent diffusion coefficient (ADC), mean diffusivity (MD) and mean kurtosis (MK) in two groups, respectively; and the consistency analysis was performed by using the interclass correlation coefficients (ICC). According to the results of postoperative pathology, all patients were divided into lymph node metastasis group and lymph node non-metastasis group; ADC, MD, MK of both groups were compared. The pathological diagnosis results were taken as the gold standard, receiver operating characteristic (ROC) curves of DKI quantitative parameters in the diagnosis of lymph node metastasis of rectal cancer were plotted, the area under the curve (AUC) was calculated, the optimal diagnostic threshold was determined based on the Yoden index, and the sensitivity and specificity were calculated.Results:The ICC of ADC, MD and MK calculated by two physicians were 0.934 (0.833-0.975), 0.963 (0.905-0.981) and 0.971 (0.949-0.991), respectively, showing a good inter-observer consistency. Among the 79 patients with rectal adenocarcinoma, 36 cases were in lymph node metastasis group and 43 cases were in lymph node non-metastasis group. MK value in lymph node metastasis group was higher than that in lymph node non-metastasis group, and the difference was statistically significant (0.97±0.08 vs. 0.89±0.09; t = -4.07, P < 0.001), while the ADC and MD values in lymph node metastasis group were lower than those in lymph node non-metastasis group, and the differences were not statistically significant (all P > 0.05). The AUC of MK value in the diagnosis of lymph node metastasis of rectal cancer was 0.735, and the corresponding sensitivity and specificity were 55.56% and 88.37%, respectively. Conclusions:DKI quantitative parameter MK has a certain diagnostic value in predicting lymph node metastasis of rectal cancer.

Keeping abreast with cutting-edge measurement and assessment techniques for complex noise in the workplace / 环境与职业医学

Complex noise is the dominant type of noise in workplaces. It can cause more serious hearing loss than steady-state noise. The existing noise measurement and evaluation standards based on the "equal energy hypothesis" are not completely suitable for complex noise. This paper introduced the status quo of workplace noise measurement and assessment techniques, and the research progress of workplace complex noise measurement and assessment techniques. In terms of future research in this area, four proposals were made, including to improve associated population database, develop and revise noise-related standards, establish methodology of kurtosis adjustment, and identify the incidence characteristics of kurtosis-related occupational hearing loss. The paper also introduced the special column "Measurement and assessment techniques of complex noise in the workplace".

Measuring method of occupational non-Gaussian noise exposure based on kurtosis adjustment / 环境与职业医学

The existing measuring methods of noise exposure on the basis of equal energy hypothesis are applicable to Gaussian noise while not fully applicable to non-Gaussian noise. Studies have shown that temporal structure (kurtosis) combined with noise energy has the potential to quantify non-Gaussian noise exposure effectively. However, there is no unified measuring method adopting this joint metric. In this paper, the measuring method of non-Gaussian noise exposure based on kurtosis adjustment was introduced, detailing measurement indicators, adjustment schemes, applicable objects, instrument requirements, and measurement steps. Adjusting the exposure duration of cumulative noise exposure (CNE) by kurtosis or adjusting the equivalent continuous A-weighted sound pressure level (LAeq) by an adjustment coefficient based on animal or population studies can more accurately quantify workers' exposure to non-Gaussian noise and improve the underestimation of hearing loss caused by non-Gaussian noise. A large number of population studies are warranted in the future to verify the effectiveness of these two adjustment schemes.

Applying kurtosis-adjusted cumulative noise exposure to assess occupational hearing loss among furniture manufacturing workers / 环境与职业医学

Background Occupational noise-induced hearing loss (NIHL) is one of the most prevalent occupational diseases in the world. With the development of industry, noise sources in the workplace have become increasingly complex. Objective To apply kurtosis-adjusted cumulative noise exposure (CNE) to assess the occupational hearing loss among furniture manufacturing workers, and to provide a basis for revising noise measurement methods and occupational exposure limits in China. Methods A cross-sectional survey was conducted to select 694 manufacturing workers, including 542 furniture manufacturing workers exposed to non-Gaussian noise, and 152 textile manufacturing workers and paper manufacturing workers exposed to Gaussian noise. The job titles involving non-Gaussian noise were gunning and nailing, and woodworking, while those involving Gaussian noise were weaving, spinning, and pulping. High frequency noise-induced hearing loss (HFNIHL) and noise exposure data were collected for each study subject. Noise energy metrics included eight-hour equivalent continuous A-weighted sound pressure level (LAeq,8 h) and CNE. Kurtosis was a noise temporal structure metric. Kurtosis-adjusted CNE was a combined indicator of noise energy and temporal structure. Results The age of the study subjects was (35.64±10.35) years, the exposure duration was (6.71±6.44) years, and the proportion of males was 75.50%. The LAeq,8 h was (89.43±6.01) dB(A). About 81.42% of the study subjects were exposed to noise levels above 85 dB(A), the CNE was (95.85±7.32) dB(A)·year, with a kurtosis of 99.34 ± 139.19, and the prevalence rate of HFNIHL was 35.59%. The mean kurtosis of the non-Gaussian noise group was higher than that of the Gaussian noise group (125.33±147.17 vs. 5.86±1.94, t=−21.04, P<0.05). The results of binary logistic regression analysis showed that kurtosis was an influential factor of workers' HFNIHL after correcting for age, exposure duration, and LAeq,8 h (OR=1.49, P<0.05). The results of multiple linear regression analysis showed that the effects of age, exposure duration, LAeq,8 h, and kurtosis on noise-induced permanent threshold shift at frequencies of 3, 4, and 6 kHz of the poor hearing ear were statistically significant (all P<0.05). The results of chi-square trend analysis showed that when CNE ≥ 90 dB(A)·year, the HFNIHL prevalence rate elevated with increasing kurtosis (P<0.05). The mean HFNIHL prevalence rate was higher in the non-Gaussian noise group than in the Gaussian noise group (31.7% vs. 22.0%, P<0.05). After applying kurtosis-adjusted CNE, the linear equation between CNE and HFNIHL prevalence rate for the non-Gaussian noise group almost overlapped with that for the Gaussian noise group, and the mean difference in HFNIHL prevalence rate between the two groups decreased from 9.7% to 1.4% (P<0.05). Conclusion Noise kurtosis is an effective metric for NIHL evaluation. Kurtosis-adjusted CNE can effectively evaluate occupational hearing loss due to non-Gaussian noise exposure in furniture manufacturing workers, and is expected to be a new indicator of non-Gaussian noise measurement and assessment.

Applying kurtosis-adjusted equivalent continuous A-weighted sound pressure level to evaluate risk of occupational hearing loss associated with non-steady state noise / 环境与职业医学

Background Equivalent continuous A-weighted sound pressure level is not appropriate for evaluating the risk of non-steady noise exposure, and need to be corrected by noise time-domain structure, but the correction method and its applicability need to be discussed. Objective To validate the application of the kurtosis-adjusted normalization of equivalent continuous A-weighted sound pressure level to a normal 8 h working day ( LAeq,8 h) in assessing noise-induced hearing loss (NIHL), and to improve the methods for assessing occupational hearing loss associated with different types of noise. Methods Audiometric and shift-long noise exposure data were acquired from a population(n=2 466) of screened workers exposed to noise between 70 dB(A) and 95 dB(A) from 6 industries in China. The cohort data were collapsed into 1 dB(A) bins, and the average kurtosis and noise-induced permanent threshold shifts at 3 kHz, 4 kHz, and 6 kHz (NIPTS346) within 1 dB(A) were calculated respectively. According to the existing correction method, the adjustment coefficient λ was calculated by multiple regression, and LAeq,8 h was corrected by λ (L'Aeq,8 h). The entire cohort was divided into K1 (≤10; steady noise), K2 (10~50; non-steady noise), and K3 (＞50; non-steady noise) groups based on mean kurtosis levels. Predicted NIPTS346 was calculated using the ISO 1999 model for each participant and the actual measured NIPTS346 was corrected for age and gender. The underestimated NIPTS346 was the difference between the values of estimated NIPTS346 and the corresponding actual NIPTS346. To validate the applicability of L′Aeq,8 h in evaluating NIHL, the correlation between L′Aeq,8 h and HFNIHL, and the mean difference between real NIPTS346 and estimated NIPTS346 were analyzed. Results The adjustment coefficient λ was determined at 5.43. The results of multiple logistic regression analysis showed that the relationship between L'Aeq,8 h and HFNIHL increased from 6.6% to 9.6% after the kurtosis adjustment. The DRR of LAeq,8 h and HFNIHL showed that the percentage of HFNIHL decreased after the adjustment of kurtosis in the non-steady noise groups, and the regression lines of the non-steady noise groups approached that of the steady noise group. The R2 of the K2 group increased from 0.935 3 to 0.986 3, and the R 2 of the K3 group increased from 0.905 6 to 0.951 6. Under the un-adjusted condition, the NIPTS346 underestimation for the K3 group was significantly higher than that for the steady noise group (t=−3.23, P=0.001). After the LAeq,8 h was adjusted by kurtosis, the NIPTS346 underestimation decreased significantly in the three kurtosis groups (K1: t=6.78, P＜0.001; K2: t=14.31, P＜0.001; K3: t=11.06, P＜0.001). There was no significant difference in the degree of underestimation between the three kurtosis groups (K1 vs K2: t=−0.22, P=0.830; K1 vs K3: t=−1.40, P=0.205) as the curves of the three kurtosis groups were nearly overlapped. Conclusion The kurtosis-adjusted LAeq,8 h can effectively estimate the hearing loss associated with non-steady state noise.

Quantitative study of diffusion kurtosis imaging in Parkinson disease with dysosmia / 中风与神经疾病杂志

@#Objective　To investigate the microstructure changes of brain regions of interest in patients with Parkinson disease with dysosmia using diffusion kurtosis imaging.Methods　DKI scanning was performed in 16 patients with dysosmia and 21 patients without dysosmia.Supramarginal gyrus,postcentral gyrus,heschl gyrus and inferior temporal gyrus were selected as regions of interest.Results　The values of FA,KFA,AK and RK in the region of interest in the Parkinson disease group with dysosmia were significantly lower than those without dysosmia (P<0.05);the values of AD,MD and RD in the region of interest in the Parkinson disease group with dysosmia were significantly higher than those without dysosmia (P<0.05);There was a close correlation between the olfactory score and the right supramarginal gyrus,postcentral gyrus,inferior temporal gyrus,bilateral heschl gyrus in the Parkinson disease group with dysosmia (P<0.05).Conclusion　DKI parameters can be used as biomarkers for early diagnosis of dysosmia in Parkinson disease.

Epidemiological characteristics of noise-induced hearing loss among workers in five automobile manufacturing enterprises in Zhejiang Province / 环境与职业医学

Background Noise is the most common occupational hazard in the automobile manufacturing industry with the most workers exposed. Automobile manufacturing industry is a high-risk industry for noise-induced hearing loss. Objective To understand the epidemiological characteristics of noise-induced hearing loss among workers in automobile manufacturing industry and explore related influencing factors. Methods A questionnaire survey, individual noise recording, and pure tone audiometry were conducted among workers (n=656) exposed to noise from five automobile manufacturing enterprises. The data on age, sex, exposure duration, noise intensity, kurtosis, and hearing loss were obtained. The positive rates of high-frequency noise-induced hearing loss (HFNIHL) and speech-frequency noise-induced hearing loss (SFNIHL) were calculated, and each factor was compared between workers with and without HFNIHL. Chi-square test and analysis of trend were conducted among different groups of age, sex, exposure duration, A-weighted equivalent continuous sound pressure level normalized to a nominal 8-hour working day (LAeq,8h), and kurtosis. Logistic regression analysis was conducted to analyze the factors influencing the positive rates of HFNIHL and SFNIHL. Results The exposure rates of non-Gaussian noise was 73.6%. The positive rates of HFNIHL and SFNIHL were 32.6% (214 workers) and 6.7% (44 workers), respectively. The HFNIHL workers showed older age, higher proportion of male, longer exposure duration, higher noise intensity (LAeq,8 h), and increased kurtosis than those without HFNIHL (P<0.05). The positive rates of HFNIHL increased with the increase of age, exposure duration, LAeq,8 h, and kurtosis (\begin{document}$ {\chi

Kurtosis assessment of high frequency hearing loss caused by complex noise / 中国职业医学

@#Abstract: Objective To investigate the feasibility of kurtosis in evaluating high frequency hearing loss (HFHL) caused by Methods - complex noise. A total of 273 noise exposed workers in three metal tool manufacturing enterprises were chosen as studysubjectsusingajudgementsamplingmethod.Thenoiseintensityandkurtosisintheworkplacewasmeasured.Cumulative noiseexposure(CNE)wascalculatedfromnoiseintensityandworkingageandtheCNEwasadjustedusingkurtosis(CNE′).CNEResultsandCNE′wereusedtoevaluatetheriskofHFHL,andtheeffectsofthetwomethodswerecompared.ThemedianandMPP25,75percentiles[(25,75)]ofnoiseexposedintensityinthestudysubjectswas91.9(88.3,97.3)dB(A),andtheincidenceofMPPnoiseexposureexceededthenationaloccupationalexposurelimitaccountedfor81.0%.The(25,75)ofthekurtosiswas8.3 (7.9, 27.3), and kurtosis>4.0 accounted for 100.0%. The detection rate of HFHL was 39.6% (108/273). The detection rate of P - - HFHL increased with the increase of CNE and CNE′ (all <0.01). The goodness of fit of CNE′ in assessing the risk of HFHL Conclusion detectionwasbetterthanthatofCNE(coefficientsofdeterminationwere0.91and0.83,respectively). Kurtosiscan beusedasanauxiliaryparametertoadjusttheCNEandthenappliedtoevaluatetheriskofHFHLcausedbycomplexnoise.Keywords:Hearingloss;Noise;Strength;Kurtosis;Cumulativenoiseexposure;Riskassessment

Clinical application and progress of quantitative functional magnetic resonance imaging in prostate cancer / 中南大学学报(医学版)

Magnetic resonance imaging (MRI) is a very important imaging method for diagnosis and treatment of prostate cancer (PCa) in clinical practice. As functional MRI is growing and maturing, its quantitative parameters are expected to enhance the clinical value of MRI furtherly. Intravoxel incoherent motion diffusion imaging, diffusion tensor imaging, and diffusion kurtosis imaging, which were derived from diffusion weighted imaging, have provided richer and more accurate parameters. The newly-developed magnetic resonance elastography can complement the mechanical characteristics of PCa.

Application of temporal kurtosis index in assessing hearing loss caused by complex noise / 中国职业医学

Complex noise with impulse or impact property is common in workplace, and its damage on the auditory system is greater than that of steady-state noise. At present, the noise exposure measurement and evaluation indicators widely used in the world mainly include the equivalent continuous sound level and the cumulative noise exposure, both are based on the equal energy hypothesis(EEH). EEH only considered the damage of noise energy on the auditory system, but ignored the effect of temporal characteristics of noise, and underestimated the degree of hearing loss associated with complex noise. This paper first introduced the limitations of current noise exposure assessment standards at home and abroad, then introduced the definition of temporal kurtosis and the calculation method of its related energy indexes(such as cumulative noise exposure and equivalent continuous A-weighted sound pressure level), and further summarized the effectiveness of temporal kurtosis as an auxiliary parameter of noise energy in assessing the risk of hearing loss caused by complex noise, providing a rationale to supplement the existing noise assessment standards.

Correlations of cognitive dysfunction with subcortical nuclei volumes and diffusion kurtosis imaging parameters in patients with aneurysmal subarachnoid hemorrhage after surgery / 中华神经医学杂志

Objective:To observe the changes of cognitive function, subcortical nuclei volumes, and diffusion kurtosis imaging (DKI) parameters (values of fractional anisotropy [FA], mean diffusivity [MD] and mean kurtosis [MK]) after surgery in patients with aneurysmal subarachnoid hemorrhage (aSAH), and analyze the correlations of cognitive dysfunction with subcortical nuclei volumes and DKI parameters.Methods:A prospective sutdy was conducted;17 patients with aSAH confirmed by surgery in our hospital from September 2019 to June 2020 were selected as patient group, and 16 healthy volunteers whose age, gender, and education level were matched with the patient group were recruited as control group. Neuropsychological tests and MR imaging were performed in the patients 3 months after surgery and the controls right after enrollment. The structural image data of all subjects were post-processed. Bilateral subcortical nuclei volumes and DKI parameters were analyzed. The differences of general clinical data, subcortical nuclei volumes and DKI parameters were compared between the two groups. The correlations of mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) scores with subcortical nuclei volumes and DKI parameters were analyzed.Results:As compared with the control group, the patient group had significantly lower MMSE and MoCA scores, and statistically decreased volumes of ipsilateral hippocampus, ipsilateral thalamus and ipsilateral lentiform nucleus ( P<0.05). The FA values of the contralateral caudate nucleus, bilateral thalamus and bilateral lentiform nucleus and MK values of the ipsilateral hippocampus in the patient group were significantly decreased as compared with those in the control group ( P<0.05); while the MD values of the ipsilateral caudate nucleus in the patient group were significantly increased as compared with those in the control group ( P<0.05). The volume of ipsilateral hippocampus was positively with MoCA scores ( r=0.604, P=0.038); the FA values of contralateral caudate nucleus were negatively correlated with MMSE scores ( r=-0.579, P=0.049). Conclusions:Cognitive dysfunction, atrophy of ipsilateral hippocampus, thalamus and lenticular nucleus, and changes of DKI parameters exist in patients with aSAH after surgery. The changes in ipsilateral hippocampus volume and FA values of caudate nucleus may be related to the postoperative cognitive dysfunction in these patients.

Evaluation of microstructural changes of brain parenchyma in patients with essential hypertension by diffuse kurtosis imaging and enhanced T2 star weighted angiography / 中华神经医学杂志

Objective:To evaluate the microstructural changes of brain parenchyma in patients with essential hypertension by diffuse kurtosis imaging (DKI) and enhanced T2 star weighted angiography (ESWAN).Methods:A prospective study was performed; 27 patients with essential hypertension, admitted to our hospital from April 2019 to September 2019, and 16 healthy subjects matched with gender, age and education level were enrolled in our study. According to the presence or absence of cerebral microbleeds (CMBs), patients with essential hypertension were divided into essential hypertension with CMBs group ( n=8) and essential hypertension without CMBs group ( n=19). MRI, DKI and ESWAN were performed on all subjects. The mean kurtosis (MK), mean diffusivity (MD) and fractional anisotropy (FA) of bilateral hippocampal gyrus, centrum semiovale, caudate head, posterior limb of internal capsule, thalamus, red nucleus, substantia nigra, pons, and cerebellum were measured. Results:As compared with the healthy subjects, the patients with essential hypertension had significantly lower MK values in the left semioval center, bilateral caudate head, left posterior limb of internal capsule, and bilateral thalamus, significantly higher MD value in the right thalamus, and statistically lower FA value in the left posterior limb of internal capsule ( P<0.05). The essential hypertension with CMBs group had significantly lower MK values in left hippocampus gyrus, left centrum semiovale, bilateral caudate head, left posterior limb of internal capsule, bilateral thalamus, and left substantia nigra, significantly higher MD value in right thalamus, and significantly lower FA value in left posterior limb of internal capsule as compared with essential hypertension without CMBs group and healthy control group ( P<0.05). Conclusion:In patients with essential hypertension, the brain microstructural changes are found in the hippocampus, centrum semiovale, caudate head, posterior limb of internal capsule, thalamus and substantia nigra; these changes are more obvious in essential hypertension patients with CMBs; DKI and ESWAN can effectively assess the early brain microstructure changes in patients with essential hypertension.

Evaluation of the efficacy of QSM combined with DKI in the treatment of Parkinson’s disease with dopamine receptor agonist / 中风与神经疾病杂志

@#Objective　To evaluate the efficacy of QSM combined with DKI in the treatment of Parkinson’s disease. Methods　In June 2016 to December 2018 in the Beihua University neurology patients diagnosed with Parkinson’s disease of 60 cases and 20 healthy volunteers as control group. All patients taking Madopar，UPDRS score，magnetic sensitive quantitative imaging （QSM），and diffusion kurtosis imaging （DKI） were performed before and six months after treatment to evaluate the changes of patients’ condition. All volunteers underwent magnetic sensitivity quantitative imaging （QSM） and diffusion kurtosis imaging （DKI） examination. Two doctors manually drew the range of ROI for the deep nuclear masses of both cerebral hemispheres：substantia nigra，red nucleus，putamen，caudate nucleus，thalamus and globule，and measured the mean kurtosis （MK） value of DKI parameters and the value of magnetic susceptibility. Statistical analysis was performed on the relevant data. Results　There were no lateral differences in the magnetic susceptibility and MK values of each nuclear group before and after treatment （P>0.05），The patient was treated with madopar for six months，the UPDRS score of the patients was （17.0±0.87），significantly lower than that of （19.0±0.68） before treatment，and the difference was statistically significant （P<0.05），Before treatment，the magnetic susceptibility of bilateral substantia nigra，red nucleus，shell nucleus，caudate nucleus and globus pallidus was significantly higher than that of normal control group （P<0.05），the magnetic susceptibility values of bilateral substantia nigra and putamen decreased compared with that before treatment，and the difference was statistically significant （P<0.05），the MK values of bilateral substantia nigra，left red nucleus，left caudate nucleus and bilateral colliculus before treatment were significantly higher than those of normal group （P<0.05），after treatment，the MK values of the left melanocytes，red nuclei and right melanocytes were 0.936±0.430，0.883±0.377 and 1.017±0.474，respectively，which were significantly higher than that before treatment （0.588±0.216，0.581±0.235 and 0.603±0.210），with statistically significant differences （P<0.05）. Finally，when comparing the correlations of UPDRS score with MK value and susceptibility value，the susceptibility value of the patient’s left putamen was significantly correlated with the patient’s UPDRS score （P<0.05）. Conclusion　Madopar has a good effect in the treatment of Parkinson’s disease. QSM combined with DKI provides an objective basis for the detection of Madopar efficacy，among which the magnetization value of the left putamen has a significant correlation with UPDRS score.

Quantitative assessment of white matter damage caused by delayed neuropsychiatric sequelae after carbon monoxide poisoning with diffusion kurtosis imaging / 中华神经医学杂志

Objective To investigate the value of quantitative evaluation in white matter damage caused by delayed neuropsychiatric sequelae (DNS) after carbon monoxide poisoning (CO) with diffuse kurtosis imaging (DKI).Methods A prospective study was conducted from November 2016 to February 2019 in 28 patients diagnosed as having DNS after CO poisoning and 30 healthy controls in our hospital.DKI scans were performed within 7 d of onset and DKI-derived parameters (9 regions of interest),including mean kurtosis (MK),axial kurtosis (AK),and radial kurtosis (RK),were obtained.Mini Mental State Examination Scale (MMSE),Barthel Index,Verbal Fluency Test (VFT),and Digital Breadth Test (DST) were performed on both subjects to conduct neurocognitive assessment;multivariate regression analysis was performed to determine the statistical relations of scores of above neurocognitive scales with AK values of ROIs.Results As compared with those in the control group,the MK,AK and RK values in all ROIs showed an increased trend in DNS group;among which,the anterior semioval center,posterior semioval center and frontal lobe enjoyed the most obvious increase,with significant differences (P＜0.05).In the genu of corpus callosum,body of corpus callosum and parietal lobe,the AK value of DNS group was significantly higher than that in the controls (P＜0.05).Except for temporal lobe and occipital lobe,area under the curve (AUC) of AK value of other ROIs in diagnosing DNS was larger than that of RK and MK values of other ROIs;AK value of anterior semioval center (AUC=0.802,P=0.000),posterior semioval center (AUC=0.785,P=0.000),frontal lobe (AUC=0.749,P=0.001),genu of corpus callosum,(AUC=0.730,P=0.003),parietal lobe (AUC=0.699,P=0.009) and body of corpus callosum (AUC=0.654,P=0.045) had better performance than RK and MK in diagnosing DNS,with statistically significant differences (P＜0.05).Multivariate regression analysis results show that the DST value (reverse) is the independent influencing factors of AK values of anterior semioval center,genu of corpus callosum,and frontal lobe;VET (vegetable) is the independent influencing factors of AK values of body of corpus callosum,age is the independent influencing factors of AK values of posterior semioval center,splenium of corpus callosum,and frontal,temporal and occipital lobes;and education is the independent influencing factors of AK values of temporal lobe.Conclusion DKI can quantitatively evaluate the microstructural damage of white matter caused by DNS,and the increase of AK is related to the decrease of neurological function in patients with DNS.