Machine learning-based nomogram: integrating MRI radiomics and clinical indicators for prognostic assessment in acute ischemic stroke.

Background: Acute Ischemic Stroke (AIS) remains a leading cause of mortality and disability worldwide. Rapid and precise prognostication of AIS is crucial for optimizing treatment strategies and improving patient outcomes. This study explores the integration of machine learning-derived radiomics signatures from multi-parametric MRI with clinical factors to forecast AIS prognosis. Objective: To develop and validate a nomogram that combines a multi-MRI radiomics signature with clinical factors for predicting the prognosis of AIS. Methods: This retrospective study involved 506 AIS patients from two centers, divided into training (n = 277) and validation (n = 229) cohorts. 4,682 radiomic features were extracted from T1-weighted, T2-weighted, and diffusion-weighted imaging. Logistic regression analysis identified significant clinical risk factors, which, alongside radiomics features, were used to construct a predictive clinical-radiomics nomogram. The model's predictive accuracy was evaluated using calibration and ROC curves, focusing on distinguishing between favorable (mRS ≤ 2) and unfavorable (mRS > 2) outcomes. Results: Key findings highlight coronary heart disease, platelet-to-lymphocyte ratio, uric acid, glucose levels, homocysteine, and radiomics features as independent predictors of AIS outcomes. The clinical-radiomics model achieved a ROC-AUC of 0.940 (95% CI: 0.912-0.969) in the training set and 0.854 (95% CI: 0.781-0.926) in the validation set, underscoring its predictive reliability and clinical utility. Conclusion: The study underscores the efficacy of the clinical-radiomics model in forecasting AIS prognosis, showcasing the pivotal role of artificial intelligence in fostering personalized treatment plans and enhancing patient care. This innovative approach promises to revolutionize AIS management, offering a significant leap toward more individualized and effective healthcare solutions.

Exploring disparities in surgical recommendations for patients with primary intramedullary spinal cord tumors: an analysis of the Surveillance, Epidemiology, and End Results database from 2000 to 2019.

OBJECTIVE: Factors that may drive recommendations for operative intervention for patients with intramedullary spinal cord tumors (ISCTs) have yet to be extensively studied. The authors investigated racial and socioeconomic disparities in the management of patients with primary spinal cord ependymomas and nonependymal gliomas, with the aim of determining the associations between socioeconomic patient characteristics, survival, and recommendations for the resection of primary ISCTs. METHODS: The Surveillance, Epidemiology, and End Results registry was queried to identify all patients > 18 years of age with ISCTs diagnosed between 2000 and 2019. Univariable and multivariable logistic regression analyses were used to calculate odds ratios for variables associated with receiving a surgical recommendation. Log-rank tests and multivariable Cox proportional hazards models were used to investigate overall survival (OS) and disease-specific survival (DSS). RESULTS: The authors identified 2325 patients (mean age 49 [SD 16] years; 48.8% female; 67.4% non-Hispanic White, 7.8% non-Hispanic Black, 16.2% Hispanic, 6.5% Asian/Pacific Islander, 0.6% Native American; 56.7% married; 64.4% with household income < $75,000; 73.8% with spinal ependymoma; and 26.2% with nonependymal spinal glioma). Eighty-seven percent of patients received a surgical recommendation. In multivariable models, marriage was associated with higher odds of receiving a surgical recommendation for ependymomas (OR 1.80, p = 0.005). In multivariable models for nonependymal spinal gliomas, older age (OR 0.98, p = 0.001) and increased number of tumors (OR 0.62, p = 0.015) were associated with decreased odds of receiving surgical recommendations. Among ependymomas, marriage (HR 0.59, p = 0.001), younger age (HR 0.93, p < 0.001), female sex (HR 0.43, p = 0.006), and decreased number of tumors (HR 0.56, p < 0.001) were associated with improved OS. Among nonependymal spinal gliomas, median household income ≥ $75,000 (HR 0.69, p = 0.020) and younger age (HR 0.98, p < 0.001) were associated with improved DSS, while Black race (HR 4.65, p = 0.027) and older age (HR 1.05, p < 0.001) were associated with worse OS. CONCLUSIONS: In patients with spinal ependymomas and nonependymal spinal gliomas, recommendations for surgery appear to be unaffected by patient sex, race, or income. Survival disparities appear to exist among unmarried, male, Black, and lower-income cohorts. Continued initiatives to identify drivers of disparities while improving health equity in this patient population are needed.

Assessment of progression of pulmonary fibrosis based on metabonomics and analysis of intestinal microbiota.

The main purpose of this study was to explore the changes of biomarkers in different developmental stages of bleomycin-induced pulmonary fibrosis (PF) in rats via comprehensive pathophysiology, UPLC-QTOF/MS metabonomic technology, and 16S rRNA gene sequencing of intestinal microbiota. The rats were randomly divided into normal control and 1-, 2- and 4-week model group. The rat model of PF was established by one-time intratracheal instillation of bleomycin. The levels of inflammatory and fibrosis-related factors such as hydroxyproline (HYP), type III procollagen (COL-III), type IV collagen (COL-IV), hyaluronidase (HA), laminin (LN), interleukin (IL)-1ß, IL-6, malondialdehyde (MDA) increased and superoxide dismutase (SOD) decreased as the PF cycle progressed. In the 1-, 2- and 4-week model group, 2, 19 and 18 potential metabolic biomarkers and 3, 16 and 12 potential microbial biomarkers were detected, respectively, which were significantly correlated. Glycerophospholipid metabolism pathway was observed to be an important pathway affecting PF at 1, 2 and 4 weeks; arginine and proline metabolism pathways significantly affected PF at 2 weeks. Linoleic acid metabolism pathway exhibited clear metabolic abnormalities at 2 and 4 weeks of PF, and alpha-linolenic acid metabolism pathway significantly affected PF at 4 weeks.

In this study, metabolomics technology and intestinal microbiota 16S rRNA gene sequencing were used to search for biomarkers with significant differences in each stage of pulmonary fibrosis. Finally, the variation characteristics of each stage of the disease were discussed. The hope is to provide new insights into the development of diagnostic biomarkers and potential therapeutic targets at all stages.

Association of socioeconomic status with the management outcome of unruptured intracranial arteriovenous malformation.

OBJECTIVE: The longitudinal management of unruptured brain arteriovenous malformation (bAVM) is crucial. To date, no study in the United States has evaluated the impact of socioeconomic status (SES) on bAVM outcome. Herein, the authors aimed to clarify the impact of SES, as indicated by the area deprivation index (ADI), on bAVM outcome. METHODS: A retrospective analysis of an institutional bAVM database was conducted. Non-hereditary hemorrhagic telangiectasia patients with a single unruptured bAVM in the period from 1990 to 2021 were included in the analysis. The ADI was categorized as low (ADI ≤ 15th percentile), mid (15th percentile < ADI < 85th percentile), and high (ADI ≥ 85th percentile), with a low ADI indicating the most advantaged group. Patient baseline and follow-up data were analyzed. The primary outcome of interest was nonindependence (modified Rankin Scale [mRS] score > 2) at the last follow-up. A multivariable logistic regression model was performed. RESULTS: A total of 589 patients with unruptured bAVMs were included in the study. The mean patient age at diagnosis was 37.2 years, and 283 patients (48.0%) were male. Of the bAVMs, 238 (40.4%) had a low Spetzler-Martin grade (SMG < III), 194 (32.9%) had a moderate grade (SMG III), and 157 (26.7%) had a high grade (SMG > III). Sixty-nine patients (11.7%) were in the low-ADI group, 476 (80.8%) in the mid-ADI group, and 44 (7.5%) in high-ADI group. Increasing age (OR 1.02, 95% CI 1.01-1.04, p < 0.001), poor baseline mRS score (OR 3.27, 95% CI 1.32-7.88, p = 0.008), treatment with surgery plus radiosurgery with or without embolization (OR 3.21, 95% CI 1.03-9.81, p = 0.041), mid SMG (OR 1.94, 95% CI 1.11-3.44, p = 0.021), high SMG (OR 2.08, 95% CI 1.13-3.88, p = 0.020), longer follow-up (OR 1.05, 95% CI 1.03-1.08, p < 0.001), and mid ADI (OR 3.08, 95% CI 1.34-8.39, p = 0.015) were significantly associated with a poor outcome. A high ADI tended toward a poor outcome (OR 2.93, 95% CI 0.92-9.88, p = 0.071). Eventual obliteration of a bAVM was the only protective predictor of poor outcome (OR 0.55, 95% CI 0.30-0.98, p = 0.046). CONCLUSIONS: This study revealed that relatively disadvantaged patients with unruptured bAVMs are more likely to experience nonindependent outcomes at the last follow-up, after adjusting for confounding variables. An emphasis on social support may be beneficial for patients with a lower SES.

A protein panel in cerebrospinal fluid for diagnostic and predictive assessment of Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disease with heterogenous pathophysiological changes that develop years before the onset of clinical symptoms. These preclinical changes have generated considerable interest in identifying markers for the pathophysiological mechanisms linked to AD and AD-related disorders (ADRD). On the basis of our prior work integrating cerebrospinal fluid (CSF) and brain proteome networks, we developed a reliable and high-throughput mass spectrometry-selected reaction monitoring assay that targets 48 key proteins altered in CSF. To test the diagnostic utility of these proteins and compare them with existing AD biomarkers, CSF collected at baseline visits was assayed from 706 participants recruited from the Alzheimer's Disease Neuroimaging Initiative. We found that the targeted CSF panel of 48 proteins (CSF 48 panel) performed at least as well as existing AD CSF biomarkers (Aß42, tTau, and pTau181) for predicting clinical diagnosis, FDG PET, hippocampal volume, and measures of cognitive and dementia severity. In addition, for each of those outcomes, the CSF 48 panel plus the existing AD CSF biomarkers significantly improved diagnostic performance. Furthermore, the CSF 48 panel plus existing AD CSF biomarkers significantly improved predictions for changes in FDG PET, hippocampal volume, and measures of cognitive decline and dementia severity compared with either measure alone. A potential reason for these improvements is that the CSF 48 panel reflects a range of altered biology observed in AD/ADRD. In conclusion, we show that the CSF 48 panel complements existing AD CSF biomarkers to improve diagnosis and predict future cognitive decline and dementia severity.

Is there more to bitcoin mining than carbon emissions?

Critics decry cryptocurrency mining as a huge waste of energy, while proponents insist on claiming that it is a green industry. Is Bitcoin mining really worth the energy it consumes? The high power consumption of cryptocurrency mining has become the latest global flashpoint. In this paper, we define the Mining Domestic Production (MDP) as a method to account for the final outcome of the Bitcoin mining industry's production activities in a certain period time, calculate the carbon emission per unit output value of the Bitcoin mining industry in China, and compare it with three other traditional industries. The results show that Bitcoin mining does not always have the highest when compared with others. The contribution of this paper is that we give a new perspective on thinking whether Bitcoin mining is more efficient to make more profit, in terms of the same amount of carbon emissions per unit compared to other industries. Moreover, it could even be argued that Bitcoin may present an opportunity for some developing countries to build out their electrical capacity and generate revenue.

Status of epilepsy in the tropics: An overlooked perspective.

Epilepsy is one of the most common serious chronic neurological diseases affecting people of all ages globally. It is characterized by recurrent seizures. About 50 million people worldwide have epilepsy. Indubitably, people with epilepsy (PWE) may be without access to appropriate treatment. Many studies have examined the molecular mechanisms and clinical aspects of epilepsy; nonetheless, the treatment gap exists in some special areas. In the tropics, the specific geographical and ecological conditions and a lack of medical resources result in neglect or delay of diagnosis for PWE. Herein, we summarized the epidemiology of epilepsy in the tropics and discussed the disease burden and existing problems, aiming to offer a medical environment for patients in need and highlight the importance of reducing the epileptic disease burden in tropical countries.

Non-Invasive Assessment of Intracranial Hypertension in Patients with Traumatic Brain Injury Using Computed Tomography Radiomic Features: A Pilot Study.

This study aimed to assess intracranial hypertension in patients with traumatic brain injury non-invasively using computed tomography (CT) radiomic features. Fifty patients from the primary cohort were enrolled in this study. The clinical data, pre-operative cranial CT images, and initial intracranial pressure readings were collected and used to develop a prediction model. Data of 20 patients from another hospital were used to validate the model. Clinical features including age, sex, midline shift, basilar cistern status, and ventriculocranial ratio were measured. Radiomic features-i.e., 18 first-order and 40 second-order features- were extracted from the CT images. LASSO method was used for features filtration. Multi-variate logistic regression was used to develop three prediction models with clinical (CF model), first-order (FO model), and second-order features (SO model). The SO model achieved the most robust ability to predict intracranial hypertension. Internal validation showed that the C-statistic of the model was 0.811 (95% confidence interval [CI]: 0.691-0.931) with the bootstrapping method. The Hosmer Lemeshow test and calibration curve also showed that the SO model had excellent performance. The external validation results showed a good discrimination with an area under the curve of 0.725 (95% CI: 0.500-0.951). Although the FO model was inferior to the SO model, it had better prediction ability than the CF model. The study shows that the radiomic features analysis, especially second-order features, can be used to evaluate intracranial hypertension non-invasively compared with conventional clinical features, given its potential for clinical practice and further research.

Lexical Features of Economic Legal Policy and News in China Since the COVID-19 Outbreak.

Lexical features are influenced by different languages and genres. The study of lexical features in different genres of texts on the same topic is helpful to understand the universalities and peculiarities of languages. This study constructs a research on the lexical feature and word collocations of two self-build corpora (China's economic Legal Policy Corpus and English News Corpus during the COVID-19 pandemic), the methods of Quantitative Linguistics and context interpretation are adopted. It was found that: (1) the word length, word frequency, word cluster and high frequency word distribution in English economic news and Chinese economic legal policies are influenced by language and genre to some extent, and they conform to different functional image distribution; (2) during the COVID-19 pandemic, "development" has been the focus of China's economic legal policies and English news, the two have attached importance to economic recovery and taken a positive attitude toward it in different ways. These findings suggest that: (1) There are some universalities and peculiarities between English economic news and Chinese economic legal policies in the distribution of lexical feature; (2) there is a certain synchronization between laws and news, and both of them maintain a positive and objective attitude toward the economic development during the pandemic. This study carries out a macroscopic investigation on internal structure and external interpretation, which enriches the study on lexical features and cultural features of language and provides some references for relevant studies.

Social-economic impact of infection after cosmetic facial injection: A retrospective study.

BACKGROUND: The overwhelming interest in economically cost-effective treatments had led to an increase in the development of cosmetic facial injections. Concomitantly, complications have been also on the increasing trend. This article aimed to investigate the social-economic impact caused by infection after cosmetic facial injection. METHODS: A retrospective study was conducted between January 2014 and December 2019. Information including demographics, location of the original injection site, treatments, economic loss, and time away from work associated with complications was documented. Patients were asked to complete 2 FACE-Q domains 4 weeks after the first presentation, including quality of life and patient experience. RESULTS: Complete data were available for 12 patients. All patients were female; the mean age was 32.66 years (range, 26-49 years). The mean therapeutic cost of atypical mycobacterium was 18170.58 USD. The mean time away from work was 51.25 days (range, 21-103 days). The mean cost of time away from work was 400.80 USD (range, 164.23-805.50 USD). From FACE-Q, patients reported a decreased quality of social life, including social function (38.83 ± 12.10), psychological distress (48.67 ± 11.01), and early-life impact (39.92 ± 10.15). Patients also reported low satisfaction with their decision to undergo the cosmetic facial injection. CONCLUSIONS: Infection after cosmetic facial injection comes at a considerable social-economic impact on patients. Patients who responded in this study were extremely unsatisfied with the quality of life following the infection.

Natural attenuation of sulfometuron-methyl in seawater: Kinetics, intermediates, toxicity change and ecological risk assessment.

This research aims to evaluate the environmental feasibility of sulfometuron-methyl (SM) as a growth inhibitor for restricting the growth of Spartina alterniflora. To achieve this purpose, the natural attenuation characteristics, ecological risk, degradation pathway, and comprehensive toxicity changes of SM in seawater were investigated under the simulated marine environmental conditions of Jiaozhou Bay, China. The natural attenuation of SM in seawater followed first-order reaction kinetics with a rate constant (K) of 0.0694 d-1 and a half-life of 9.99 days. When photolysis, hydrolysis, and biodegradation pathways act alone, the rate constants K of SM were 0.0167, 0.0143, and 0.0099 d-1 respectively, indicating that their contributions to the total removal of SM decreased in turn. The calculation results of risk quotient (RQ) showed that the seawater containing 10 mg/L of SM demonstrated a very high risk to marine diatom Skeletonema costatum before and after 21 days of attenuation with RQ values of 24.46 and 6.32, respectively, however, the risk to other marine organisms (fish, crustaceans, and bivalves) decreased from moderate (RQ < 1) to low (RQ < 0.01). Four attenuation products of SM were identified and two degradation pathways of SM in seawater were proposed. Based on the rate of inhibition of bioluminescence, SM in seawater was not harmful to Photobacterium phosphoreum T3, whereas the toxicity of seawater containing SM increased with the extension of attenuation time, suggesting the formation of intermediate products with high aquatic toxicity. According to the toxicity values predicted by ECOSAR, the toxicity of one identified attenuation product was higher than that of SM. To the best of our knowledge, this is the first report on the attenuation characteristics and toxicity changes of SM in seawater. The results indicated that the toxicity of both SM and its degradation products to non-target marine organisms should be considered in evaluating the feasibility of SM in controlling coastal Spartina alterniflora.

Cost-Effectiveness Analysis of Imaging Modalities for Breast Cancer Surveillance Among BRCA1/2 Mutation Carriers: A Systematic Review.

BACKGROUND: BRCA1/2 mutation carriers are suggested with regular breast cancer surveillance screening strategies using mammography with supplementary MRI as an adjunct tool in Western countries. From a cost-effectiveness perspective, however, the benefits of screening modalities remain controversial among different mutated genes and screening schedules. METHODS: We searched the MEDLINE/PubMed, Embase, Cochrane Library, Scopus, and Web of Science databases to collect and compare the results of different cost-effectiveness analyses. A simulated model was used to predict the impact of screening strategies in the target group on cost, life-year gained, quality-adjusted life years, and incremental cost-effectiveness ratio (ICER). RESULTS: Nine cost-effectiveness studies were included. Combined mammography and MRI strategy is cost-effective in BRCA1 mutation carriers for the middle-aged group (age 35 to 54). BRCA2 mutation carriers are less likely to benefit from adjunct MRI screening, which implies that mammography alone would be sufficient from a cost-effectiveness perspective, regardless of dense breast cancer. CONCLUSIONS: Precision screening strategies among BRCA1/2 mutation carriers should be conducted according to the acceptable ICER, i.e., a combination of mammography and MRI for BRCA1 mutation carriers and mammography alone for BRCA2 mutation carriers. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, identifier CRD42020205471.

Cost-effectiveness analysis of using the TBX6-associated congenital scoliosis risk score (TACScore) in genetic diagnosis of congenital scoliosis.

BACKGROUND: We previously reported a novel clinically distinguishable subtype of congenital scoliosis (CS), namely, TBX6-associated congenital scoliosis (TACS). We further developed the TBX6-associated CS risk score (TACScore), a multivariate phenotype-based model to predict TACS according to the patient's clinical manifestations. In this study, we aimed to evaluate whether using the TACScore as a screening method prior to performing whole-exome sequencing (WES) is more cost-effective than using WES as the first-line genetic test for CS. METHODS: We retrospectively collected the molecular data of 416 CS patients in the Deciphering disorders Involving Scoliosis and COmorbidities (DISCO) study. A decision tree was constructed to estimate the cost and the diagnostic time required for the two alternative strategies (TACScore versus WES). Bootstrapping simulations and sensitivity analyses were performed to examine the distributions and robustness of the estimates. The economic evaluation considered both the health care payer and the personal budget perspectives. RESULTS: From the health care payer perspective, the strategy of using the TACScore as the primary screening method resulted in an average cost of $1074.2 (95%CI: $1044.8 to $1103.5) and an average diagnostic duration of 38.7d (95%CI: 37.8d to 39.6d) to obtain a molecular diagnosis for each patient. In contrast, the corresponding values were $1169.6 (95%CI: $1166.9 to $1172.2) and 41.4d (95%CI: 41.1d to 41.7d) taking WES as the first-line test (P < 0.001). From the personal budget perspective, patients who were predicted to be positive by the TACScore received a result with an average cost of $715.1 (95%CI: $594.5 to $835.7) and an average diagnostic duration of 30.4d (95%CI: 26.3d to 34.6d). Comparatively, the strategy of WES as the first-line test was estimated to have significantly longer diagnostic time with an average of 44.0d (95%CI: 43.2d to 44.9d), and more expensive with an average of $1193.4 (95%CI: $1185.5 to $1201.3) (P < 0.001). In 100% of the bootstrapping simulations, the TACScore strategy was significantly less costly and more time-saving than WES. The sensitivity analyses revealed that the TACScore strategy remained cost-effective even when the cost per WES decreased to $8.8. CONCLUSIONS: This retrospective study provides clinicians with economic evidence to integrate the TACScore into clinical practice. The TACScore can be considered a cost-effective tool when it serves as a screening test prior to performing WES.

Phytotoxicity Assessment of Copper Oxide Nanoparticles on the Germination, Early Seedling Growth, and Physiological Responses in Oryza sativa L.

The increasing utilization of copper oxide nanoparticles (CuO NPs) and their release into the environment has made it imperative to elucidate their impact on the ecological system including plants. However, their potential toxic impact and mechanisms on plant growth are still unclear. The aim of this study was to investigate the effects of CuO NPs and released Cu ions on seed germination and early seedling growth, as well as physiological and biochemical parameters of Oryza sativa. The results showed that CuO NPs at high concentration significantly inhibited seed germination and early seedling growth. The toxicity of CuO NPs originated from the particulate NPs rather than the released Cu2+. The phytotoxicity of CuO NPs to rice seed germination and seedling growth probably induced by high Cu accumulation along with the lignification and oxidative damage. The work presented here will increase our knowledge of phytotoxicity of CuO NPs.

Examining the functional range of commercially available low-cost airborne particle sensors and consequences for monitoring of indoor air quality in residences.

Low-cost airborne particle sensors are gaining attention for monitoring human exposure to indoor particulate matter. This study aimed to establish the concentrations at which these commercially available sensors can be expected to report accurate concentrations. We exposed five types of commercial integrated devices and three types of "bare" low-cost particle sensors to a range of concentrations generated by three different sources. We propose definitions of upper and lower bounds of functional range based on the relationship between a given sensor's output and that of a reference instrument during a laboratory experiment. Experiments show that the lower bound can range from approximately 3 to 15 µg/m3 . At greater concentrations, sensor output deviates from linearity at approximately 300-3000 µg/m3 . We also conducted a simulation campaign to analyze the effect of this limitation on functional range on the accuracy of exposure readings given by these devices. We estimate that the upper bound results in minimal inaccuracy in exposure quantification, and the lower bound can result in as much as a 50% error in approximately 10% of US homes.

BMCGM: A Behavior Economics-Based Message Transmission Cooperation Guarantee Mechanism in Vehicular Ad-hoc NETworks.

Vehicular Ad-hoc NETwork (VANET) is a special mobile ad hoc network that composed of facilities such as vehicle nodes and roadside units. Message transfer among vehicle nodes has been a great challenge due to the network's highly variable topology and the selfish nature of vehicle nodes. Thus, it is very necessary to propose a mechanism to improve the cooperation among vehicle nodes to guarantee the effective message transmission. Currently, incentive-based cooperation mechanisms are commonly used to encourage nodes to participate in message transmission. Those mechanisms are based on traditional economics and generally assume that the decision-making behavior of nodes is completely independent. Also, the cooperation of nodes depends on whether the cooperation behavior can obtain the higher utility. But researches in behavioral economics have shown that due to the existence of altruistic reciprocity, the behavior of nodes is affected by not only their utility but also the behavioral motives of other nodes, so as to obtain different results from traditional incentive-based mechanisms. Therefore, the paper introduces the reciprocal altruistic from behavioral economics and proposes the reciprocal altruistic factor to reconstruct the utility function of nodes. The reconstructed utility function reflects the interaction of behavioral motives among nodes, which promotes the node's cooperative behavior. Also, since the Network Formation Game (NFG) is a common mathematical model for studying the interaction and communication links formation among network nodes, hence the paper regards NFG in traditional economics as the research object. A Behavior Economics-based Message Transmission Cooperation Guarantee Mechanism named BMCGM is proposed, which motivates nodes to participate in the message transmission to reduce the transmission delay ratio. The simulation results show that the BMCGM reduces message transmission delay by at least 30.3% compared with the recent representative cooperation transmission mechanism.

Comparison of apparent diffusion coefficient and T2 relaxation time variation patterns in assessment of age and disc level related intervertebral disc changes.

PURPOSE: To compare the variation patterns of ADC and T2 values in different age and intervertebral disc (IVD) levels, thus to identify their sensitivities in assessing age and disc level related IVDs changes. MATERIALS AND METHODS: The T2 and ADC values were recorded from 345 IVDs of 69 volunteers. Kendall's correlation analysis was used to identify the relationship between age and T2/ADC mean values respectively. The one-way analysis of variance (ANOVA) with post hoc analysis was then applied to test the differences of T2 and ADC values among different IVD levels and age groups, followed by linear regression analysis between age (<45 and >45 years) and T2/ADC mean values. This study was approved by the Ethics Committee of the Chinese Academy of Medical Sciences and the Peking Union Medical College Hospital. RESULTS: Significant negative correlation was observed between age and T2/ADC mean values. The T2 and ADC values showed significant differences among IVD levels and among age groups except for T2 values in age group 1 (25-34 years) and group 2 (35-44 years), and for ADC values at L1-2 level. Both T2 and ADC values showed significant differences between young (age<45 years) and elderly group (age>45 years) at each IVD level. A linear relationship was observed between age and T2/ADC mean values in the elderly group as well as in the young group for the ADC mean values, while no such tendency was identified in the young group for the T2 mean values. CONCLUSIONS: ADC values may be a more sensitive parameter than T2 in assessing age and disc level related intervertebral disc changes.