Transfer learning with CNNs for efficient prostate cancer and BPH detection in transrectal ultrasound images.

Early detection of prostate cancer (PCa) and benign prostatic hyperplasia (BPH) is crucial for maintaining the health and well-being of aging male populations. This study aims to evaluate the performance of transfer learning with convolutional neural networks (CNNs) for efficient classification of PCa and BPH in transrectal ultrasound (TRUS) images. A retrospective experimental design was employed in this study, with 1380 TRUS images for PCa and 1530 for BPH. Seven state-of-the-art deep learning (DL) methods were employed as classifiers with transfer learning applied to popular CNN architectures. Performance indices, including sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), Kappa value, and Hindex (Youden's index), were used to assess the feasibility and efficacy of the CNN methods. The CNN methods with transfer learning demonstrated a high classification performance for TRUS images, with all accuracy, specificity, sensitivity, PPV, NPV, Kappa, and Hindex values surpassing 0.9400. The optimal accuracy, sensitivity, and specificity reached 0.9987, 0.9980, and 0.9980, respectively, as evaluated using twofold cross-validation. The investigated CNN methods with transfer learning showcased their efficiency and ability for the classification of PCa and BPH in TRUS images. Notably, the EfficientNetV2 with transfer learning displayed a high degree of effectiveness in distinguishing between PCa and BPH, making it a promising tool for future diagnostic applications.

Gamma Knife Radiosurgery as a Salvage Treatment for Nasopharyngeal Carcinoma with Skull Base and Intracranial Invasion (T4b).

It is usually difficult to achieve good outcomes with salvage treatment for recurrent nasopharyngeal carcinoma (NPC) because of its deep-seated location, surrounding critical structures, and patient history of high-dose irradiation. Gamma Knife radiosurgery (GKS) is a treatment option for malignancies with skull base and intracranial invasion. We conducted a retrospective, observational, single-center study including 15 patients with recurrent NPC (stage T4b) involving the skull base and intracranial invasion, who underwent GKS as a salvage treatment. Patients were enrolled over 12 years. Per a previous study, the TNM classification T4b was subclassified into T4b1 and T4b2, defined as the involvement of the skull base or cavernous sinus with an intracranial extension of <5 mm and >5 mm, respectively. The effect of prognostic factors, including age, sex, survival period, magnetic resonance imaging (MRI) presentation, presence of other distant metastases, tumor volume, marginal dose, maximal dose, and Karnofsky Performance Status (KPS), on outcomes was analyzed. The patients with T4b1 NPC (p = 0.041), small tumor volume (p = 0.012), higher KPS (p < 0.001), and no other metastasis (p = 0.007) had better outcomes after GKS treatment, suggesting that it is a viable treatment modality for NPC. We also suggest that detailed brain imaging studies may enable the early detection of intracranial invasion.

Segmentation of liver tumors with abdominal computed tomography using fully convolutional networks.

BACKGROUND: Dividing liver organs or lesions depicting on computed tomography (CT) images could be applied to help tumor staging and treatment. However, most existing image segmentation technologies use manual or semi-automatic analysis, making the analysis process costly and time-consuming. OBJECTIVE: This research aims to develop and apply a deep learning network architecture to segment liver tumors automatically after fine tuning parameters. METHODS AND MATERIALS: The medical imaging is obtained from the International Symposium on Biomedical Imaging (ISBI), which includes 3D abdominal CT scans of 131 patients diagnosed with liver tumors. From these CT scans, there are 7,190 2D CT images along with the labeled binary images. The labeled binary images are regarded as gold standard for evaluation of the segmented results by FCN (Fully Convolutional Network). The backbones of FCN are extracted from Xception, InceptionresNetv2, MobileNetv2, ResNet18, ResNet50 in this study. Meanwhile, the parameters including optimizers (SGDM and ADAM), size of epoch, and size of batch are investigated. CT images are randomly divided into training and testing sets using a ratio of 9:1. Several evaluation indices including Global Accuracy, Mean Accuracy, Mean IoU (Intersection over Union), Weighted IoU and Mean BF Score are applied to evaluate tumor segmentation results in the testing images. RESULTS: The Global Accuracy, Mean Accuracy, Mean IoU, Weighted IoU, and Mean BF Scores are 0.999, 0.969, 0.954, 0.998, 0.962 using ResNet50 in FCN with optimizer SGDM, batch size 12, and epoch 9. It is important to fine tuning the parameters in FCN model. Top 20 FNC models enable to achieve higher tumor segmentation accuracy with Mean IoU over 0.900. The occurred frequency of InceptionresNetv2, MobileNetv2, ResNet18, ResNet50, and Xception are 9, 6, 3, 5, and 2 times. Therefore, the InceptionresNetv2 has higher performance than others. CONCLUSIONS: This study develop and test an automated liver tumor segmentation model based on FCN. Study results demonstrate that many deep learning models including InceptionresNetv2, MobileNetv2, ResNet18, ResNet50, and Xception have high potential to segment liver tumors from CT images with accuracy exceeding 90%. However, it is still difficult to accurately segment tiny and small size tumors by FCN models.

Efficient Strike Artifact Reduction Based on 3D-Morphological Structure Operators from Filtered Back-Projection PET Images.

Positron emission tomography (PET) can provide functional images and identify abnormal metabolic regions of the whole-body to effectively detect tumor presence and distribution. The filtered back-projection (FBP) algorithm is one of the most common images reconstruction methods. However, it will generate strike artifacts on the reconstructed image and affect the clinical diagnosis of lesions. Past studies have shown reduction in strike artifacts and improvement in quality of images by two-dimensional morphological structure operators (2D-MSO). The morphological structure method merely processes the noise distribution of 2D space and never considers the noise distribution of 3D space. This study was designed to develop three-dimensional-morphological structure operators (3D MSO) for nuclear medicine imaging and effectively eliminating strike artifacts without reducing image quality. A parallel operation was also used to calculate the minimum background standard deviation of the images for three-dimensional morphological structure operators with the optimal response curve (3D-MSO/ORC). As a result of Jaszczak phantom and rat verification, 3D-MSO/ORC showed better denoising performance and image quality than the 2D-MSO method. Thus, 3D MSO/ORC with a 3 × 3 × 3 mask can reduce noise efficiently and provide stability in FBP images.

Integrating ECG Monitoring and Classification via IoT and Deep Neural Networks.

Anesthesia assessment is most important during surgery. Anesthesiologists use electrocardiogram (ECG) signals to assess the patient's condition and give appropriate medications. However, it is not easy to interpret the ECG signals. Even physicians with more than 10 years of clinical experience may still misjudge. Therefore, this study uses convolutional neural networks to classify ECG image types to assist in anesthesia assessment. The research uses Internet of Things (IoT) technology to develop ECG signal measurement prototypes. At the same time, it classifies signal types through deep neural networks, divided into QRS widening, sinus rhythm, ST depression, and ST elevation. Three models, ResNet, AlexNet, and SqueezeNet, are developed with 50% of the training set and test set. Finally, the accuracy and kappa statistics of ResNet, AlexNet, and SqueezeNet in ECG waveform classification were (0.97, 0.96), (0.96, 0.95), and (0.75, 0.67), respectively. This research shows that it is feasible to measure ECG in real time through IoT and then distinguish four types through deep neural network models. In the future, more types of ECG images will be added, which can improve the real-time classification practicality of the deep model.

Classification for liver ultrasound tomography by posterior attenuation correction with a phantom study.

The B-mode ultrasound usually contains scattering speckle noise which reduces the detailed resolution of the target and is regarded as an intrinsic noise that interferes with diagnostic precision. The aim of this study was to classify hepatic steatosis through applying attenuation correction with a phantom to reduce speckle noise in liver ultrasound tomography in patients. This retrospective study applied three randomized groups signifying different liver statuses. A total of 114 patients' effective liver ultrasound images-30 normal, 44 fatty, and 40 cancerous-were included. The proposed depth attenuation correction method was first applied to images. Three regions of interest were manually drawn on the images. Next, five feature values for the regions of interest were calculated. Finally, the hybrid method of logistic regression and support vector machine was employed to classify the ultrasound images with 10-fold cross-validation. The accuracy, kappa statistic, and mean absolute error of the proposed hybrid method were 87.5%, 0.812, and 0.119, respectively, which were higher than those of the logistic regression method-75.0%, 0.548, and 0.280-or those of the support vector machine method-75.7%, 0.637, and 0.293-respectively. Therefore, the hybrid method has been proven to be more accurate and have better performance and less error than either single method. The hybrid method provided acceptable accuracy of classification in three liver ultrasound image groups after depth attenuation correction. In the future, the deep learning approaches may be considered for the application in classifying liver ultrasound images.

Low accuracy of chromogranin A for diagnosing early-stage pancreatic neuroendocrine tumors.

The aim of the present study was to evaluate the clinical utility of plasma chromogranin A (CgA) in patients diagnosed with early-stage pancreatic neuroendocrine tumors (PNETs) in terms of diagnostic value and treatment response. A total of 35 patients with PNETs were prospectively enrolled from August 2010 to April 2014. Demographic and clinicopathological data were collected, and serial plasma CgA levels were measured. Tumor responses were defined by the Response Evaluation Criteria In Solid Tumors criteria. Pearson's χ2 test was used for the analysis of the association between the plasma CgA level and various factors. Plasma CgA level was significantly associated with the size (P=0.03), metastasis (P=0.02) and tumor stage (P=0.03) of the PNETs. Using 126 U/l as the optimal cutoff value, the sensitivity and specificity were 87.5 and 81.5%, respectively. For localized tumors, the sensitivity of CgA for diagnosing PNETs was relatively low, even following a lowering of the cutoff values (29.6-51.9%). Plasma CgA level was correlated with therapeutic response in those patients with high baseline CgA levels (P=0.025), but not in the patients with low baseline CgA levels (P=0.587). In conclusion, plasma CgA level was associated with tumor size, metastasis and tumor stage in patients with PNET. For early-stage PNETs, CgA exhibited a limited role in diagnosis and treatment response evaluation in the population of the present study.

Effects of nurse-led lower extremity strength training on knee function recovery in patients who underwent total knee replacement.

AIMS AND OBJECTIVES: To examine the effects of lower extremity muscle strength training on knee function recovery and quality of life in patients who underwent total knee replacement. BACKGROUND: Patients with knee osteoarthritis after surgery experience decreased knee function that impacts their quality of life. However, patients typically lack a long-term, home-based and continuous leg exercise training method and rarely have studies explored the effects of exercise training on knee function recovery and quality of life. DESIGN: A experimental and longitudinal study design. METHODS: The simple randomised sampling (based on patients' admission priority order) was used to collect participant data. Outcome measurements included the Knee Injury and Osteoarthritis Outcome Score. Participants were randomised to receive and starting lower extremity muscle strength training before surgery (training group, n = 100) or to receive usual care (nontraining group, n = 100). Data were collected and followed up with the patients before surgery (T1) and at 2 weeks (T2), 1 month (T3), 2 months (T4) and 3 months (T5) after discharge. RESULTS: The Knee Injury and Osteoarthritis Outcome Score subscale scores showed that both groups of patients experienced knee function and quality of life decreases 2 weeks after total knee replacement, but all subscale scores gradually increased from the first month to the third month after total knee replacement. Both groups and times were significantly different, but the training group's knee function and quality of life recovered earlier and better than the nontraining group does. CONCLUSIONS: This study confirmed that lower extremity muscle strength training helps to improve quality of life and knee function in patients who undergo total knee replacement. Healthcare staff should include this training in presurgical nursing care and in patients' discharge plans as a continuous, daily rehabilitation activity at home. RELEVANCE TO CLINICAL PRACTICE: When patients are diagnosed with knee osteoarthritis and undergo surgery, a presurgical exercise education and discussion of knee function rehabilitation should be part of standard care.

The risk of cataractogenesis after gamma knife radiosurgery: a nationwide population based case-control study.

BACKGROUND: Medical radiation is considered a factor responsible for cataractogenesis. However, the incidence of this ophthalmologic complication resulting from gamma knife radiosurgery (GKRS) has not yet been reported. The present study aimed to determine the risk of cataractogenesis associated with radiation exposure from GKRS. METHODS: This study used information from a random sample of one million persons enrolled in the nationally representative Taiwan National Health Insurance Research Database. The GK group consisted of patients who underwent GKRS between 2000 and 2009. The non-GK group was composed of subjects who had never undergone GKRS, but who were matched with the case group for time of enrollment, age, sex, history of coronary artery disease, hypertension, and diabetes. RESULTS: There were 277 patients in the GK group and 2770 matched subjects in the non-GK group. The GK group had a higher overall incidence of cataracts (10.11% vs. 7.26%; crude hazard ratio [cHR], 1.59; 95% CI, 1.07-2.36; adjusted hazard ratio [aHR], 1.25; 95% CI, 0.82-1.90) than the non-GK group. Patients who had undergone computed tomography and/or cerebral angiography (CT/angio) studies had a higher risk of developing cataracts than those who did not (10.82% vs. 6.64%; cHR, 1.74; 95% CI, 1.31-2.30; aHR, 1.65; 95% CI, 1.22-2.23). The age group between 30 and 50 years had the highest risk of cataractogenesis in both the GK and CT/angio groups (cHR, 3.50; 95% CI, 1.58-7.72; aHR, 2.43; 95% CI, 1.02-5.81; cHR, 2.96; 95% CI, 1.47-5.99; aHR, 2.27; 95% CI, 1.05-4.93, respectively). CONCLUSIONS: Radiation exposure due to GKRS and CT/angio study may be independently associated with increased risk of cataractogenesis. We suggest routine dosimetry measurement of eye lens and proper protection for patients with benign lesions during GKRS. Regular follow-up imaging studies should avoid the use of CT/angio, and particular care should be taken in the 30-50-year-old age group, due to their significantly increased risk of cataract formation.

Comparative effectiveness of nucleos(t)ide analogues in chronic hepatitis B patients undergoing cytotoxic chemotherapy.

BACKGROUND: Comparative effectiveness of different nucleos(t)ide analogues for preventing hepatitis B virus reactivation induced by cytotoxic chemotherapy has not been elucidated. The prophylactic drug of choice remains controversial. AIM: Our objective was to compare the effectiveness of tenofovir, telbivudine and entecavir with lamivudine in preventing the reactivation of hepatitis B virus caused by chemotherapy. METHODS: This retrospective cohort study consecutively screened all patients who were positive for hepatitis B virus surface antigen and received chemotherapy for malignant diseases in a teaching hospital in Taiwan. Eligible patients were grouped according to whether they received nucleos(t)ide analogues before (prophylactic group) or during chemotherapy (historical control). Those who received antiviral prophylaxis were further classified by the medications that included lamivudine, telbivudine, entecavir and tenofovir. The incidence of hepatitis, liver decompensation and interruption of chemotherapy were audited. RESULTS: A total of 212 consecutive patients were enrolled into analysis. Those who prophylactically used nucleos(t)ide analogues (n = 177) had significantly lower rates of liver decompensation (0.6% vs 20%, P < 0.01), interruption of chemotherapy (0% vs 40%, P < 0.01) and incidence of hepatitis (4.5% vs 100%, P < 0.01), as compared with their historical control (n = 35). In the prophylactic group, there was no difference among tenofovir, telbivudine, entecavir and lamivudine users in the incidence of hepatitis, liver decompensation and interruption of chemotherapy. CONCLUSION: Lamivudine, telbivudine, entecavir and tenofovir are all effective as the prophylactic antiviral therapy to prevent reactivation of hepatitis B induced by chemotherapy.

Diagnosed chest lesion on diffusion-weighted magnetic resonance images using apparent diffusion coefficients.

PURPOSE: A novel diagnostic method using the standard deviation (SD) value of apparent diffusion coefficient (ADC) by diffusion-weighted (DWI) magnetic resonance imaging (MRI) is applied for differential diagnosis of primary chest cancers, metastatic tumors and benign tumors. MATERIALS AND METHODS: This retrospective study enrolled 27 patients (20 males, 7 female; age, 15-85; mean age, 68) who had thoracic mass lesions in the last three years and underwent an MRI chest examination at our institution. In total, 29 mass lesions were analyzed using SD of ADC and DWI. Lesions were divided into five groups: Primary lung cancers (N = 10); esophageal cancers (N = 5); metastatic tumors (N = 8); benign tumors (N = 3); and inflammatory lesions (N = 3). Quantitative assessment of MRI parameters of mass lesions was performed. The ADC value was acquired based on the average of the entire tumor area. The error-plot, t-test and the area under receiver operating characteristic (AUC) were applied for statistical analysis. RESULTS: The SD of ADC value (mean±SD) was (4.867±1.359)×10-4 mm2/sec in primary lung cancers, and (3.598±0.350)×10-4 mm2/sec in metastatic tumors. The SD of ADC values of primary lung cancers and metastatic tumors (P <  0.05) were significantly different and the AUC was 0.800 (P <  0.05). The means of SD of ADC values was 4.532±1.406×10-4 mm2/sec and 2.973±0.364×10-4 mm2/sec for malignant tumors (including primary lung cancers, esophageal cancers) and benign tumors with respectively. The mean of SD of ADC values between malignant chest tumors and benign chest tumors was shown significant difference (P <  0.01). The values of AUC was 0.967 between malignant chest tumors and benign chest tumors (P <  0.05). The ADC values for primary lung cancers, metastatic tumors and benign tumors were not significantly difference (P >  0.05). CONCLUSIONS: The mean of SD of ADC value by DWI can be used for differential diagnosis of chest lesions.

Lower urinary tract symptoms of prostate cancer patients undergoing treatments over eight-month follow-up.

AIMS AND OBJECTIVES: To examine the changes in lower urinary tract symptoms after open radical prostatectomy, laparoscopic radical prostatectomy and brachytherapy and to determine which treatment resulted in improved lower urinary tract symptoms at 8 months follow-up. BACKGROUND: Lower urinary tract symptoms are a primary side effect after prostate cancer treatment. DESIGN: A time-series survey design with descriptive and comparative elements. METHODS: A sample of 51 prostate cancer patients was recruited: open radical prostatectomy = 20, laparoscopic radical prostatectomy = 23 and brachytherapy = 8. Data were collected at six time points: before treatment/baseline, 1 week post-treatment, 1 month post-treatment, 2 month post-treatment, 3 month post-treatment and 8 months post-treatment. The lower urinary tract symptoms were assessed using the International Prostate Symptom Score, with a higher score indicating a worse condition. One-way anova was used to predict the progress of urinary symptoms after treatments. Bootstrap re-sampling was conducted to assess the stability of the outcomes. RESULTS: Although there were no significant differences in the lower urinary tract symptoms among the three groups after treatments, the laparoscopic radical prostatectomy group had the lowest International Prostate Symptom Score score at baseline. Compared with the baseline symptoms for patients undergoing each treatment, there were significant improvements after 2 months in the open radical prostatectomy and brachytherapy groups, and after 3 months in the laparoscopic radical prostatectomy group. CONCLUSIONS: The prostate cancer patients undergoing the three treatments have similar lower urinary tract symptoms over 8-month follow-up although different lower urinary tract symptoms were presented before treatments. RELEVANCE TO CLINICAL PRACTICE: Results could be applied to educating and counselling prostate cancer patients regarding symptoms during recovery after surgery. It could also help patients better understand the outcomes related to the differing treatment methods.

Reduction in adjacent-segment degeneration after multilevel posterior lumbar interbody fusion with proximal DIAM implantation.

OBJECT Multilevel long-segment lumbar fusion poses a high risk for future development of adjacent-segment degeneration (ASD). Creating a dynamic transition zone with an interspinous process device (IPD) proximal to the fusion has recently been applied as a method to reduce the occurrence of ASD. The authors report their experience with the Device for Intervertebral Assisted Motion (DIAM) implanted proximal to multilevel posterior lumbar interbody fusion (PLIF) in reducing the development of proximal ASD. METHODS This retrospective study reviewed 91 cases involving patients who underwent 2-level (L4-S1), 3-level (L3-S1), or 4-level (L2-S1) PLIF. In Group A (42 cases), the patients received PLIF only, while in Group B (49 cases), an interspinous process device, a DIAM implant, was put at the adjacent level proximal to the PLIF construct. Bone resection at the uppermost segment of the PLIF was equally limited in the 2 groups, with preservation of the upper portion of the spinous process/lamina and the attached supraspinous ligament. Outcome measures included a visual analog scale (VAS) for low-back pain and leg pain and the Oswestry Disability Index (ODI) for functional impairment. Anteroposterior and lateral flexion/extension radiographs were used to evaluate the fusion status, presence and patterns of ASD, and mobility of the DIAM-implanted segment. RESULTS Solid interbody fusion without implant failure was observed in all cases. Radiographic ASD occurred in 20 (48%) of Group A cases and 3 (6%) of Group B cases (p < 0.001). Among the patients in whom ASD was identified, 9 in Group A and 3 in Group B were symptomatic; of these patients, 3 in Group A and 1 in Group B underwent a second surgery for severe symptomatic ASD. At 24 months after surgery, Group A patients fared worse than Group B, showing higher mean VAS and ODI scores due to symptoms related to ASD. At the final follow-up evaluations, as reoperations had been performed to treat symptomatic ASD in some patients, significant differences no longer existed between the 2 groups. In Group B, flexion/extension mobility at the DIAM-implanted segment was maintained in 35 patients and restricted or lost in 14 patients, 5 of whom had already lost segmental flexion/extension mobility before surgery. No patient in Group B developed ASD at the segment proximal to the DIAM implant. CONCLUSIONS Providing a dynamic transition zone with a DIAM implant placed immediately proximal to a multilevel PLIF construct was associated with a significant reduction in the occurrence of radiographic ASD, compared with PLIF alone. Given the relatively old age and more advanced degeneration in patients undergoing multilevel PLIF, this strategy appears to be effective in lowering the risk of clinical ASD and a second surgery subsequent to PLIF.

Scattering correction algorithm in the PET sinogram using the factorial design of experimental method: A phantom study.

Positron emission tomography (PET) had been utilized to image gene therapy, estimate tumor growth, detect neural function of the brain, and diagnose disease. However, sinogram noise always results inaccurate PET images. The factorial design of experiment (DOE), a statistical method, was applied to investigate, correct and estimate the fraction of scattering of 2D sinogram in PET. The DOE was included as factors of angle views and scatter media with two levels designed. The PET sinogram after scattering correction was then reconstructed by filtered back projection (FBP). Both Ge-68 uniform phantom and Jaszczak anthropomorphic torso phantom were applied to exam the performance of presented scattering correction algorithm. The signal-to-noise ratio (SNR), standard deviation (STD) of background, and full width at half maximum (FWHM), and uniformity test were applied to validate the performance of presented method. The proposed method provides a narrower FWHM, smaller STD of the background, higher SNR and better uniformity than those of original protocols. This method should be tested for accuracy and feasibility with three-dimensional phantoms or real animal studies and consideration effects of cross-talk between slices in future work.

Analyzed outcome for embolization of hepatic carcinoma by C-arm angiographic computed tomography.

PURPOSE: This study evaluated and monitored the outcome of angiographic embolization of hepatic carcinoma by real-time C-arm angiographic computed tomography under number of tumors, size of tumors, and patient's age.METHODS AND MARTIALS: In total, 142 patients underwent angiographic embolization of hepatic carcinoma. The control group, 71 patients, underwent conventional angiographic (CA) embolization of hepatic carcinoma. The experimental group, 71 patients, underwent C-arm angiographic computed tomography (CCT) embolization of hepatic carcinoma. The numbers of angiographic embolization, number of tumors, size of tumors, and patients ages were recorded for comparisons between groups by analysis of variance (ANOVA) with cross-interaction and the chi-square test (cross table). RESULTS: The age ranges were 20-84 and 35-84 years old for the experimental and control groups respectively. Average number of angiographic embolizations of hepatic carcinomas were 2.63 ± 1.84 and 5.32 ± 2.01 for the experimental and control groups. The number of angiographic embolizations under number of tumors, size of tumors, and patients ages between groups were significantly different (P< 0.05). The effective analyses of transcatheter arterial chemoembolization (TACE) by CCT were significant by chi-square test (P< 0.05) under ⩽ 3 cm and patients aged ⩽ 60. CONCLUSION: The main advantage by CCT for undergoing TACE under tumor size smaller than 3 cm and numbers of tumor smaller 3 times were more significantly effective than those by CA. The CCT combined with TACE had high potentially reduced numbers of undergoing TACE.

Quantifying liver cirrhosis by extracting significant features from MRI T2 image.

Most patients with liver cirrhosis must undergo a series of clinical examinations, including ultrasound imaging, liver biopsy, and blood tests. However, the quantification of liver cirrhosis by extracting significant features from a T2-weighted magnetic resonance image (MRI) provides useful diagnostic information in clinical tests. Sixty-two subjects were randomly selected to participate in this retrospective analysis with assigned to experimental and control groups. The T2-weighted MRI was obtained and to them dynamic adjusted gray levels. The extracted features of the image were standard deviation (SD), mean, and entropy of pixel intensity in the region of interest (ROI). The receiver operator characteristic (ROC) curve, 95% confidence intervals, and kappa statistics were used to test the significance and agreement. The analysis of area under ROC shows that SD, mean, and entropy in the ROI were significant between the experimental group and the control group. Smaller values of SD, mean, and entropy were associated with a higher probability of liver cirrhosis. The agreements between the extracted features and diagnostic results were shown significantly (P < 0.001). In this investigation, quantitative features of SD, mean, and entropy in the ROI were successfully computed by the dynamic gray level scaling of T2-weighted MRI with high accuracy.

Analyzing coronary artery disease in patients with low CAC scores by 64-slice MDCT.

PURPOSE: Coronary artery calcification (CAC) scores are widely used to determine risk for Coronary Artery Disease (CAD). A CAC score does not have the diagnostic accuracy needed for CAD. This work uses a novel efficient approach to predict CAD in patients with low CAC scores. MATERIALS AND METHODS: The study group comprised 86 subjects who underwent a screening health examination, including laboratory testing, CAC scanning, and cardiac angiography by 64-slice multidetector computed tomographic angiography. Eleven physiological variables and three personal parameters were investigated in proposed model. Logistic regression was applied to assess the sensitivity, specificity, and accuracy of when using individual variables and CAC score. Meta-analysis combined physiological and personal parameters by logistic regression. RESULTS: The diagnostic sensitivity of the CAC score was 14.3% when the CAC score was ≤30. Sensitivity increased to 57.13% using the proposed model. The statistically significant variables, based on beta values and P values, were family history, LDL-c, blood pressure, HDL-c, age, triglyceride, and cholesterol. CONCLUSIONS: The CAC score has low negative predictive value for CAD. This work applied a novel prediction method that uses patient information, including physiological and society parameters. The proposed method increases the accuracy of CAC score for predicting CAD.

Ischemic preconditioning ameliorates spinal cord ischemia-reperfusion injury by triggering autoregulation.

OBJECTIVE: The mechanism underlying ischemic preconditioning (IPC) protection against spinal cord ischemia-reperfusion (I/R) injury is unclear. We investigated the role of spinal cord autoregulation in tolerance to spinal cord I/R injury induced by IPC in a rat model. METHODS: Sprague-Dawley rats were randomly assigned to four groups. IPC (P) group animals received IPC by temporary thoracic aortic occlusion (AO) with a 2F Fogarty arterial embolectomy catheter (Baxter Healthcare, Irvine, Calif) for 3 minutes. The I/R injury (I/R) group animals were treated with blood withdrawal and temporary AO for 12 minutes, and shed blood reinfusion at the end of the procedures. The P+I/R animals received IPC, followed by 5 minutes reperfusion, and then I/R procedures for 12 minutes. Sham (S) group animals received anesthesia and underwent surgical preparation, but without preconditioning or I/R injury. Neurologic function on postprocedure days 1, 3, 5, and 7 was evaluated by Tarlov scoring. Lumbar segments were harvested for histopathologic examination on day 7. To evaluate the role of autoregulation in IPC, spinal cord blood flow and tissue oxygenation were continuously monitored throughout the procedure duration. RESULTS: The Tarlov scores in the I/R group were significantly lower than those in the S, P, and P+I/R groups on days 1, 3, 5, and 7 (P < .001). No significant differences were noted between the S, P, and P+I/R groups. The numbers of surviving motor neurons in the S, P, and P+I/R groups were significantly higher than those in the I/R group (P < .001); however, the number of surviving motor neurons did not differ between the S, P, and P+I/R groups. The P group exhibited higher spinal cord blood flow (P = .001-.043) and tissue oxygenation (P = .032-.043) within the first 60 minutes after reperfusion than the S group. The P+I/R group exhibited higher spinal cord blood flow (P = .016-.045) and tissue oxygenation (P = .001-.038) within the first 60 minutes after reperfusion than the I/R group. CONCLUSIONS: IPC ameliorates spinal cord I/R injury in rats, probably mediated by triggering spinal cord autoregulation and improving local spinal cord blood flow and tissue oxygenation. This concept may be the new therapeutic targets in patients requiring aortic surgery.

The relationship between brown adipose tissue activity and neoplastic status: an (18)F-FDG PET/CT study in the tropics.

BACKGROUND: Brown adipose tissue (BAT) has thermogenic potential. For its activation, cold exposure is considered a critical factor though other determinants have also been reported. The purpose of this study was to assess the relationship between neoplastic status and BAT activity by 2-deoxy-2-[(18)F]fluoro-D-glucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in people living in the tropics, where the influence of outdoor temperature was low. METHODS: (18)F-FDG PET/CT scans were reviewed and the total metabolic activity (TMA) of identified activated BAT quantified. The distribution and TMA of activated BAT were compared between patients with and without a cancer history. The neoplastic status of patients was scored according to their cancer history and (18)F-FDG PET/CT findings. We evaluated the relationships between the TMA of BAT and neoplastic status along with other factors: age, body mass index, fasting blood sugar, gender, and outdoor temperature. RESULTS: Thirty of 1740 patients had activated BAT. Those with a cancer history had wider BAT distribution (p = 0.043) and a higher TMA (p = 0.028) than those without. A higher neoplastic status score was associated with a higher average TMA. Multivariate analyses showed that neoplastic status was the only factor significantly associated with the TMA of activated BAT (p = 0.016). CONCLUSIONS: Neoplastic status is a critical determinant of BAT activity in patients living in the tropics. More active neoplastic status was associated with more vigorous TMA of BAT.