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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.
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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.
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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
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@#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
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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.
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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.
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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.
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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".
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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.
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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.
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Humans , Male , Diffusion Magnetic Resonance Imaging , Diffusion Tensor Imaging , Magnetic Resonance Imaging , Motion , Prostatic Neoplasms/diagnostic imagingABSTRACT
Objective To compare the difference in the microstructure of gray matter nucleus in basal ganglia of different movement subtypes of Parkinson's disease (PD) by diffusion kurtosis imaging (DKI) technique,and to analyze its clinical significance in the process of disease occurrence and development.Methods A total of 44 PD patients and 20 healthy controls (HC) admitted to the First Hospital of Shanxi Medical University from July 2017 to October 2018 were recruited into the study.The PD patients were classified into tremor dominant (TD) and non-tremor dominant (NTD) subtypes according to motor symptoms.All participants were scanned for DKI sequence.Fractional anisotropy (FA),mean kurtosis (MK),and mean diffusivity (MD) were obtained from bilateral red nucleus,substantia nigra,caudate nucleus,globus pallidus,putamen,and thalamus.The DKI of the deep brain nucleus in TD,NTD,HC groups was compared,and relationships between DKI and clinical measures were tested.Results Comparing the two substypes of PD with the HC group,the TD group had lower FA value (0.346±0.006 vs 0.389±0.009,U=-3.052,P=0.007),higher MK value (1.101±0.008 vs 0.981±0.006,U=-5.577,P=0.000) and higher MD value (1.005(0.919,1.082) vs 0.934 (0.899,0.970),U=2.493,P=0.038) in the substantia nigra ipsilateral to the more affected side than the HC group.The NTD group had higher MK value in the bilateral substantia nigra than the HC group (less affected side:1.090±0.022 vs 0.990±0.008,U=-4.102,P=0.000;more affected side:1.071±0.020 vs 0.981±0.006,U=-3.728,P=0.001).In the PD patients,the MK value in the substantia nigra ipsilateral to the more affected side showed a negative correlation with the Hoehn-Yahr (H-Y) grade,Unified Parkinson's Disease Rating Scale (UPDRS) Ⅲ scores,and non-tremor scores (r=-0.299,P=0.048;r=-0.366,P=0.015;r=-0.402,P=0.007).The FA values of the bilateral putamen of the TD group and the NTD group were lower than those of the HC group.The FA value in putamen contralateral to the more affected side was positively correlated with H-Y grade,UPDRS Ⅲ scores,and non-tremor scores (r=0.331,P=0.028;r=0.403,P=0.007;r=0.376,P=0.012).Compared with the HC group,the FA value of the bilateral globus pallidus was lower in the TD group.Comparing different subtypes of PD,only the FA and MK values of the bilateral thalamus were different.The tremor scores of PD patients were negatively correlated with the FA value of bilateral thalamus (less affected side:r=-0.371,P=0.013;more affected side:r=-0.402,P=0.007),and positively correlated with MK value (less affected side:r=0.547,P＜0.01;more affected side:r=0.532,P＜0.01).Conclusions The microstructure of the deep brain nucleus of PD is changed,while the TD and NTD patients have only differences in the microstructure changes of the thalamus.The changes in the microstructure of the thalamus are related to the severity of tremor in PD patients.
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Objective To compare the value of diffusion kurtosis imaging (DKI) mode and mono-exponential mode in predicting the response to neoadjuvant chemotherapy (NAC) for locally advanced breast carcinoma using DWI.Methods From January 1,2013 to December 31,2016,eighty patients with locally advanced breast carcinoma were enrolled into this prospective clinical study.The diagnosis was confirmed on the basis of histopathological results.The clinical stage stayed at Ⅱ or Ⅲ.The patients would receive breast-conserving surgery after NAC.All the patients underwent DWI examination by using both mono-exponential mode and DKI mode before chemotherapy was initiated.The parameters included ADC,mean diffusivity (MD) and mean kurtosis (MK).Within 1 to 3 days before or after MRI examination,the patients underwent aspiration biopsy,received 4 to 8 cycles of NAC and followed by surgery.According to histologic grading before NAC,the patients were classified into well-differentiated and poor-differentiated group.According to the comparison between pathological results acquired from biopsy before NAC and specimen acquired after surgery,the patients were classified into pathologic complete response (pCR) and pathologic non-complete response (non-pCR) according to treatment effect.The imaging parameters were compared between the pCR and the non-pCR group using t test.The predicting ability of two imaging modes was compared and analyzed with ROC analysis.The relationships between multiple imaging parameters,pathologic,clinical characteristics of tumor and treatment effect were analyzed using logistic multi-variate regression analysis,and further analyzed using Wald test.Results There were 30 cases of pCR and 50 cases of non-pCR.The ADC and MD values were lower in the pCR group than in the non-pCR group (P＜0.05).MK value was higher in the pCR group than in the non-pCR group (P＜0.05).ROC analysis showed that the area under ROC curve of ADC,MD and MK in predicting treatment effect were 0.732,0.866 and 0.683 respectively.Logistic regression analysis showed that,according to predicting ability,MD,ADC and MK successively were the independent predictors for the early response to chemotherapy.Conclusion Compared with mono-exponential mode,DKI mode can reflect the real micro-environment and water diffusion restriction within the tumor area more reliably and accurately,and is more suitable to serve as an imaging technique for predicting the response to NAC for locally advanced breast carcinoma.
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Objective To explore the value of diffusion kurtosis imaging (DKI) in predicting radiotherapy sensitivity of esophageal cancer from the animal model level.Methods BALB/c nude mice were subcutaneously injected with Eca-109 cell lines to form xenograft tumors.The tumors received a single dose of 15 Gy (6 MV X-rays) in the experimental group or had no any treatment as control.The volume of transplanted tumor,the change of ADC,MK and MD values,and the tumor cell density and necrosis ratio of these two groups were observed at the corresponding time points.Results The growth of xenograft volume in the experimental group was suppressed and it was significantly smaller than that in the control group (t=3.206-6.149,P＜0.05) at the 7th day after radiotherapy.From the 3rd day after radiotherapy,the ADC and MD values of the experimental group were significantly higher than those of the control group,and the MK values was lower than those in the control group (tADC =-11.018--2.049,tMD =-6.609--2.052,tMK =2.492-9.323,P＜0.05).Meanwhile,the tumor cell density of the control group was higher than that of the experimental group,and the proportion of necrosis in the experimental group was higher than that in the control group (tdensity =-8.387--2.239,t is =2.980-17.430,P＜0.05).Conclusions A single large dose radiation could inhibit the growth of xenograft.ADC,MK,MD values changed at the early stage prior to morphological changes of tumor in consistent with the change of cell density and necrosis ratio.DKI has the potential value in predicting radiotherapy sensitivity of esophageal carcinoma.
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Objective@#To investigate the difference in the microstructure of gray matter nucleus in different movement subtypes of Parkinson’s disease (PD) by diffusion kurtosis imaging (DKI) technique, and to analyze the correlation with clinical manifestations.@*Methods@#Ninety-seven patients with PD and 83 healthy controls performed conventional MRI sequence and DKI sequence scan. The PD patients were classified into gait disorder subtype (PIGD, n=57) and tremor dominant subtype (TD, n=40)subtypes according to motor symptoms. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da), radial diffusivity(Dr), mean kurtosis (MK), axial kurtosis (Ka) and radial kurtosis (Dr) maps and data were generated by software after processing. DKI was performed for all subjects and data was collected from different brain regions in both hemispheres, including red nucleus(RN), substantia nigra pars reticulate(SNr), substantia nigra pars compacta(SNc), putamen(PUT), globus pallidus(GP), head of caudate nucleus (CN)and thalamus(THA).@*Results@#TD showed a higher MMSE score(P=0.019), but lower modified Hoehn-Yahr score than that in PIGD (P<0.001), there was no significant difference of age of onset, sex, limbs of onset or disease duration between two PD subgroups. Compared with healthy controls, both TD and PIGD showed down-regulated MD, Da and Dr and up-regulated Ka values(P<0.001); MK(0.83±0.26, 0.80±0.18) was increased in SNr both in TD and PIGD, while SNc, PUT and GP (0.84±0.20, 0.75±0.07, 0.81±0.14)were decreased only in TD (P=0.017, P=0.010, P=0.020, P<0.001, P=0.002). The Kr values of PUT and CN(0.71±0.17, 0.72±0.14) were reduced in PIGD, while CN(0.70±0.14) were reduced in TD respectively (P=0.002, P=0.031, P=0.007). The MK was lower in TD than that in PIGD (t=-2.214, P=0.029), and no significant difference was found in other grey matter nuclei between TD and PIGD(P>0.05). Moreover, there was no significant correlation between DKI value and disease duration, MMSE score or Hoehn-Yahr scale (P>0.05) in TD and PIGD.@*Conclusion@#There is heterogeneity of clinical symptoms between these two subgroups of PD. DKI can quantify the microstructural changes of grey matter nucleus in different type PD patient.
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Objective@#To evaluate the diagnostic value of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) parameters in diagnosing prostate cancer(PCa) in transition zone (TZ) and stratifying pathologic Gleason grade of prostate cancer.@*Methods@#A total of 55 patients who were undergoing preoperative muti-parameters MRI of T2WI, DWI, IVIM and DKI model for the exploration of prostate cancer (January 2015 to June 2017) with pathologically confirmed by MRI-transrectal ultrasound (TRUS) targeted fusion biopsy were retrospectively included. Parameters were postprocessed by IVIM models including quantitation of perfusion fraction (f), diffusivity (D) and pseudo-diffusivity (D*) and DKI models including the mean diffusivity (MD), mean kurtosis (MK) and fractional anisotropy (FA) by outlining the 3D VOI. Independent sample t-test was used to compare the differences in lesion parameters between prostate cancer and BPH, low-risk (BPH+Gleason score 6 points) and medium-high-risk lesions (Gleason score ≥7 points). Correlation between ADC values, IVIM and DKI parameters and Gleason scores were assessed with Spearman analysis. Receiver operating characteristic curve analysis was used to evaluate the efficacy of various parameters in the differential diagnosis of prostate cancer and BPH with low-risk or high-risk.@*Results@#27 (36 focus) cases of PCa and 28 (40 focus) cases of benign prostatic hyperplasia (BPH) in PZ were included, meanwhile, the cases of GS ≥7 and and BPH+(GS=6) were 33,43,respectively. There were significant differences in ADC, D, MD, MK, and FA between patients in PCa-BHP group and high-low risk group in TZ (P<0.05), D* and f had no significant differences (P>0.05). ADC and MD showed relatively higher negativity correlations (r were -0.585 and -0.489, P<0.05) with GS of PCa in TZ. ADC exhibited a higher area under the curve (AUC 0.864) compared with D with area under the curve (AUC 0.853), however, the difference is not significant (P>0.05). Of model DKI in diagnose of PCa and BPH, the highest classification accuracy was MD(AUC 0.796). The AUC derived from multiple model parameters in different combination of ADC+D value, ADC+MD value, and ADC+MD+D value were 0.892, 0.884, and 0.897, respectively. ADC and D of IVIM model showed a significance difference between GS ≥7 and BPH+(GS=6) with a higher AUC of 0.826 and 0.743. The AUC was 0.851 of the combination of mean ADC and D, 0.846 of combination of mean ADC and MD, the AUC (0.856) of the combination of ADC, D and MD significant higher than any two combined parameters (P>0.05).@*Conclusions@#IVIM and DKI models may help to discriminate prostate cancer from BPH, and predict mid-higher GS PCa in TZ. But there is no significant advantage compared with ADC values. It is feasible to stratify the pathological grade of prostate cancer in TZ by mean ADC and MD.
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Objective@#To explore the value of diffusion kurtosis imaging (DKI) histogram analysis for differential diagnosis of prostate cancer and noncancerous foci and the correlation between histogram parameters and Gleason score.@*Methods@#Twenty-one patients were retrospectively enrolled in Beijing Hospital from May 2017 to May 2018. All subjects underwent Philips 3.0 T MR scanning. The pathologies were confirmed by in-bore MR-guided biopsy. Finally, 31 lesions were collected (two lesions each from 10 patients), including 15 prostate cancer and 16 noncancerous foci (benign prostatic hyperplasia and prostatitis). ROI was drawn manually by two experienced radiologists. All the lesions were measured mean apparent diffusion coefficient (Dapp), mean apparent kurtosis coefficient (Kapp) and their histogram parameters, the averages of two measurements were used to be calculated. The values of these parameters in cancer and noncancerous foci were compared using independent-samples t test. The Spearman test was used to evaluate the correlation of these parameters and Gleason scores of prostate cancer.@*Results@#Mean Dapp, 10th Dapp, 25th Dapp, 50th Dapp, 75th Dapp, 90th Dapp, minimum Dapp, maximum Dapp, mean Kapp, 50th Kapp, 75th Kapp, 90th Kapp, maximum Kapp between prostate cancer and noncancerous foci were statistically significant (P<0.05). 90th Kapp (r=0.630, P<0.05) and maximum Kapp (r=0.565, P<0.05) increased with the Gleason scores increasing.@*Conclusion@#Histogram analysis of DKI model is valuable for diagnosing and assessing aggressiveness of prostate cancer.
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Objective To evaluate the diagnostic value of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) parameters in diagnosing prostate cancer(PCa) in transition zone (TZ) and stratifying pathologic Gleason grade of prostate cancer. Methods A total of 55 patients who were undergoing preoperative muti?parameters MRI of T2WI, DWI, IVIM and DKI model for the exploration of prostate cancer (January 2015 to June 2017) with pathologically confirmed by MRI?transrectal ultrasound (TRUS) targeted fusion biopsy were retrospectively included. Parameters were postprocessed by IVIM models including quantitation of perfusion fraction (f), diffusivity (D) and pseudo?diffusivity (D*) and DKI models including the mean diffusivity (MD), mean kurtosis (MK) and fractional anisotropy (FA) by outlining the 3D VOI. Independent sample t?test was used to compare the differences in lesion parameters between prostate cancer and BPH, low?risk (BPH+Gleason score 6 points) and medium?high?risk lesions (Gleason score ≥7 points). Correlation between ADC values, IVIM and DKI parameters and Gleason scores were assessed with Spearman analysis.Receiver operating characteristic curve analysis was used to evaluate the efficacy of various parameters in the differential diagnosis of prostate cancer and BPH with low?risk or high?risk. Results 27 (36 focus) cases of PCa and 28 (40 focus) cases of benign prostatic hyperplasia(BPH) in PZ were included, meanwhile, the cases of GS≥7 and and BPH+(GS=6) were 33,43,respectively. There were significant differences in ADC, D, MD, MK, and FA between patients in PCa?BHP group and high?low risk group in TZ (P<0.05), D*and f had no significant differences (P>0.05). ADC and MD showed relatively higher negativity correlations (r were－0.585 and－0.489, P<0.05) with GS of PCa in TZ. ADC exhibited a higher area under the curve (AUC 0.864) compared with D with area under the curve (AUC 0.853), however, the difference is not significant (P>0.05). Of model DKI in diagnose of PCa and BPH, the highest classification accuracy was MD(AUC 0.796). The AUC derived from multiple model parameters in different combination of ADC+D value, ADC+MD value, and ADC+MD+D value were 0.892, 0.884, and 0.897, respectively. ADC and D of IVIM model showed a significance difference between GS≥7 and BPH+(GS=6) with a higher AUC of 0.826 and 0.743. The AUC was 0.851 of the combination of mean ADC and D, 0.846 of combination of mean ADC and MD, the AUC (0.856) of the combination of ADC, D and MD significant higher than any two combined parameters (P>0.05). Conclusions IVIM and DKI models may help to discriminate prostate cancer from BPH, and predict mid?higher GS PCa in TZ. But there is no significant advantage compared with ADC values. It is feasible to stratify the pathological grade of prostate cancer in TZ by mean ADC and MD.
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Objective To explore the value of diffusion kurtosis imaging (DKI) histogram analysis for differential diagnosis of prostate cancer and noncancerous foci and the correlation between histogram parameters and Gleason score. Methods Twenty?one patients were retrospectively enrolled in Beijing Hospital from May 2017 to May 2018. All subjects underwent Philips 3.0 T MR scanning. The pathologies were confirmed by in?bore MR?guided biopsy. Finally, 31 lesions were collected (two lesions each from 10 patients), including 15 prostate cancer and 16 noncancerous foci (benign prostatic hyperplasia and prostatitis). ROI was drawn manually by two experienced radiologists. All the lesions were measured mean apparent diffusion coefficient (Dapp), mean apparent kurtosis coefficient (Kapp) and their histogram parameters, the averages of two measurements were used to be calculated. The values of these parameters in cancer and noncancerous foci were compared using independent?samples t test. The Spearman test was used to evaluate the correlation of these parameters and Gleason scores of prostate cancer. Results Mean Dapp, 10th Dapp, 25th Dapp, 50th Dapp, 75th Dapp, 90th Dapp, minimum Dapp, maximum Dapp, mean Kapp, 50th Kapp, 75th Kapp, 90th Kapp, maximum Kapp between prostate cancer and noncancerous foci were statistically significant (P<0.05). 90th Kapp (r=0.630, P<0.05) and maximum Kapp (r=0.565, P<0.05) increased with the Gleason scores increasing. Conclusion Histogram analysis of DKI model is valuable for diagnosing and assessing aggressiveness of prostate cancer.
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Objective To investigate the difference in the microstructure of gray matter nucleus in different movement subtypes of Parkinson’s disease (PD) by diffusion kurtosis imaging ( DKI) technique, and to analyze the correlation with clinical manifestations. Methods Ninety-seven patients with PD and 83 healthy controls performed conventional MRI sequence and DKI sequence scan. The PD patients were classi-fied into gait disorder subtype (PIGD,n=57) and tremor dominant subtype (TD,n=40)subtypes according to motor symptoms. Fractional anisotropy (FA),mean diffusivity (MD),axial diffusivity (Da),radial diffu-sivity(Dr),mean kurtosis (MK),axial kurtosis (Ka) and radial kurtosis (Dr) maps and data were genera-ted by software after processing. DKI was performed for all subjects and data was collected from different brain regions in both hemispheres,including red nucleus(RN),substantia nigra pars reticulate( SNr),sub-stantia nigra pars compacta(SNc),putamen(PUT),globus pallidus(GP),head of caudate nucleus (CN)and thalamus(THA). Results TD showed a higher MMSE score(P=0. 019),but lower modified Hoehn-Yahr score than that in PIGD (P<0. 001),there was no significant difference of age of onset,sex,limbs of onset or disease duration between two PD subgroups. Compared with healthy controls, both TD and PIGD showed down-regulated MD,Da and Dr and up-regulated Ka values(P<0. 001); MK(0. 83±0. 26,0. 80±0. 18) was increased in SNr both in TD and PIGD,while SNc,PUT and GP (0. 84± 0. 20,0. 75± 0. 07,0. 81± 0. 14) were decreased only in TD (P=0. 017,P=0. 010,P=0. 020,P<0. 001,P=0. 002). The Kr values of PUT and CN(0. 71±0. 17,0. 72±0. 14) were reduced in PIGD,while CN(0. 70±0. 14) were reduced in TD re-spectively (P=0. 002,P=0. 031,P=0. 007). The MK was lower in TD than that in PIGD (t=-2. 214,P=0. 029),and no significant difference was found in other grey matter nuclei between TD and PIGD ( P>0. 05). Moreover,there was no significant correlation between DKI value and disease duration,MMSE score or Hoehn-Yahr scale (P>0. 05) in TD and PIGD. Conclusion There is heterogeneity of clinical symptoms between these two subgroups of PD. DKI can quantify the microstructural changes of grey matter nucleus in different type PD patient.
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Objective To compare the value of diffusion kurtosis imaging (DKI) and intravoxel incoherent motion (IVIM) in evaluation of histological classification and grading of cervical squamous cell carcinoma and cervical adenocarcinoma. Methods DKI and IVIM data of 60 patients with cervical cancer were retrospectively analyzed, and MK, MD, D, D* and f values were measured. The differences of the parameters between cervical squamous cell carcinoma group (n=38) and cervical adenocarcinoma group (n=22) were analyzed, as well as among different graded subgroups. The diagnostic efficiency of each parameter was evaluated with ROC curve, the correlations between the parameters and pathological grades were analyzed using Spearman method. Results MK of cervical squamous cell carcinoma group was higher than that of cervical adenocarcinoma group, while MD, D, D* and f were lower than those of cervical adenocarcinoma group (all P<0.05). In both groups, the differences of MK, MD and D were statistically significant among different subgroups (all P<0.05), while in cervical adenocarcinoma group, the differences of f were also statistically significant among different subgroups (all P<0.05). MK had the highest AUC in diagnosing cervical squamous cell carcinoma and adenocarcinoma.Except for D*, there was correlation between other parameters and pathological grade (all P<0.05). Conclusion Compared with IVIM, DKI can more effectively evaluate cervical squamous cell carcinoma and cervical adenocarcinoma and their pathological grading.