Altered habenular connectivity in chronic low back pain: An fMRI and machine learning study.

The habenula has been implicated in the pathogenesis of pain and analgesia, while evidence concerning its function in chronic low back pain (cLBP) is sparse. This study aims to investigate the resting-state functional connectivity (rsFC) and effective connectivity of the habenula in 52 patients with cLBP and 52 healthy controls (HCs) and assess the feasibility of distinguishing cLBP from HCs based on connectivity by machine learning methods. Our results indicated significantly enhanced rsFC of the habenula-left superior frontal cortex (SFC), habenula-right thalamus, and habenula-bilateral insular pathways as well as decreased rsFC of the habenula-pons pathway in cLBP patients compared to HCs. Dynamic causal modelling revealed significantly enhanced effective connectivity from the right thalamus to right habenula in cLBP patients compared with HCs. RsFC of the habenula-SFC was positively correlated with pain intensities and Hamilton Depression scores in the cLBP group. RsFC of the habenula-right insula was negatively correlated with pain duration in the cLBP group. Additionally, the combination of the rsFC of the habenula-SFC, habenula-thalamus, and habenula-pons pathways could reliably distinguish cLBP patients from HCs with an accuracy of 75.9% by support vector machine, which was validated in an independent cohort (N = 68, accuracy = 68.8%, p = .001). Linear regression and random forest could also distinguish cLBP and HCs in the independent cohort (accuracy = 73.9 and 55.9%, respectively). Overall, these findings provide evidence that cLBP may be associated with abnormal rsFC and effective connectivity of the habenula, and highlight the promise of machine learning in chronic pain discrimination.

Altered Amygdala-prefrontal Connectivity in Chronic Nonspecific Low Back Pain: Resting-state fMRI and Dynamic Causal Modelling Study.

Chronic nonspecific low back pain (cNLBP) is a leading contributor to disease burden worldwide that is difficult to treat due to its nonspecific aetiology and complexity. The amygdala is a complex of structurally and functionally heterogeneous nuclei that serve as a key neural substrate for the interactions between pain and negative affective states. However, whether the functions of amygdalar subcomponents are differentially altered in cNLBP remains unknown. Little attention has focused on effective connectivity of the amygdala with the cortex in cNLBP. In this study, thirty-three patients with cNLBP and 33 healthy controls (HCs) were included. Resting-state functional connectivity (rsFC) and effective connectivity of the amygdala and its subregions were examined. Our results showed that the patient group exhibited significantly greater rsFC between the left amygdala and left dorsal medial prefrontal cortex (mPFC), which was negatively correlated with pain intensity ratings. Subregional analyses suggested a difference located at the superficial nuclei of the amygdala. Dynamic causal modelling revealed significantly lower effective connectivity from the left amygdala to the dorsal mPFC in patients with cNLBP than in HCs. Both groups exhibited stronger effective connectivity from the left amygdala to the right amygdala. In summary, these findings not only suggested altered rsFC of the amygdala-mPFC pathway in cNLBP but also implicated an abnormal direction of information processing between the amygdala and mPFC in these patients. Our results further highlight the involvement of the amygdala in the neuropathology of cNLBP.

Larger regional volume of the thalamus in diarrhea-predominant irritable bowel syndrome: a cross-sectional study.

As a relay center between the cerebral cortex and various subcortical brain areas, the thalamus is repeatedly associated with the dysfunction of brain-gut interaction in patients with irritable bowel syndrome (IBS). However, the regional morphological alterations of the thalamus in IBS are not well defined. We acquired structural magnetic resonance data from 34 patients with IBS and 34 demographically similar healthy subjects. Data processing was performed using FMRIB's Integrated Registration and Segmentation Tool (FIRST). Volumetric analysis and surface-based vertex analysis were both carried out to characterize the morphology of the thalamus and other subcortical structures. Our results suggested that the majority (31 cases) of the patients with IBS had diarrhea-predominant symptoms. Volumetric analysis revealed a larger normalized volume of the right thalamus and left caudate nucleus in patients with IBS than in healthy controls. Surface analysis indicated that the difference arose mainly from the laterodorsal nucleus of the right thalamus, and the body of the left caudate nucleus. In addition, patients with IBS had different hemispheric asymmetries of the thalamus (rightward) and caudate nucleus (leftward) from controls (leftward for the thalamus and rightward for the caudate nucleus). In general, our results indicated that patients with diarrhea-predominant IBS had enlarged thalamus and caudate nucleus volumes, as well as altered hemispheric asymmetries of these two structures, compared with healthy controls. The neuroimaging evidence of these structural alterations helps clarify the underlying pathophysiology of diarrhea-predominant IBS.

GreenLight laser photoselective vaporization of the prostate for treatment of benign prostate hyperplasia/lower urinary tract symptoms in patients with different post-void residual urine.

The purpose of this study is to assess the safety and efficacy of GreenLight laser photoselective vaporization of the prostate (PVP) for the treatment of benign prostate hyperplasia/lower urinary tract symptoms (BPH/LUTS) in patients with different post-void residual urine (PVR). BPH/LUTS patients treated with PVP from January 2014 to January 2016 were enrolled in the present study. All patients were divided into PVR > 50, 50 ≤ PVR < 400, and PVR ≥ 400 ml groups, and standard general and urological methods for BPH/LUTS were carried out. PVP surgery was performed, and the follow-up outcome was investigated 6 months after surgery. A total of 429 patients were included, and there were no significant differences in comorbid diseases or habits among the three groups. The maximum urinary flow rate (Qmax) differed significantly among the groups (P < 0.001), while patients in the PVR < 50 ml group had higher maximum detrusor pressure (Pdet.max) level than the other two groups (P < 0.001). Patients in 50 ≤ PVR < 400 (P < 0.001) and PVR ≥ 400 (P < 0.001) ml groups were more likely to develop detrusor underactivity than those in the PVR < 50 ml group. All patients were treated with PVP, and there were no severe complications requiring rehospitalization or reoperation except nine designed re-treatments. Follow-up data of 387 patients were available. Significant improvement in outcome parameters (International Prostate Symptom Score [IPSS], Qmax, and PVR) was observed in comparison with baseline measurements for the three groups. PVP significantly improved the IPSS, Qmax, and PVR in patients with different PVR; PVP is a safe and effective procedure for BPH/LUTS patients.

Assessment of noninvasive predictors of bladder detrusor underactivity in BPH/LUTs patients.

PURPOSE: To retrospectively assess the diagnostic predictive value of clinical characteristics to improve the diagnostic accuracy of bladder detrusor underactivity (DU) among benign prostatic hyperplasia/lower urinary tract symptoms (BPH/LUTS) patients who cannot undergo urodynamic examinations. METHODS: A total of 704 BPH/LUTS patients at Tianjin Medical Union Center from January 2013 through June 2016 were enrolled in the study. All cases were stratified by maximum detrusor pressure (Pdet.max) into two groups (DU and control). Patient and clinical variables were analyzed in both groups. RESULTS: One hundred twelve and 592 cases were classified into the DU and control group, respectively. PV (OR 0.976, 95% CI 0.961-0.991, P = 0.002) and PVR (OR 1.004, 95% CI 1.001-1.007, P = 0.004) were independent predictors of DU. In addition, Pdet.max was positively correlated with HTN (≥10 years) (r = 0.373, P = 0.001), smoking (r = 0.108, P = 0.039), IPSS (20-23) (r = 0.257, P = 0.013), PV (r = 0.305, P < 0.001), PSA (1-2.2 ng/mL) (r = 0.428, P = 0.002), PSAD (0-0.02) (r = 0.430, P = 0.02), and Q max (≤4 mL/s) (r = 0.372, P < 0.001), and inversely correlated with age (>76 years) (r = -0.265, P = 0.015), BMI (21-23) (r = -0.382, P = 0.001), DM (0-20 years) (r = 0.365, P = 0.009) and PVR (50-400 mL) (r = 0.423, P = 0.001). The AUCs for BMI, PV, tPSA, PSAD, Q max, and PVR were 0.762, 0.739, 0.727, 0.681, 0.749, and 0.716, respectively. Combined ROC analysis showed the AUC for PV + PVR was 0.774 with sensitivity of 77.78% and specificity of 73.68%. CONCLUSION: Clinical factors were effective for predicting DU and could help improve the diagnostic accuracy for BPH/LUTS patients who cannot undergo urodynamic examinations.

Prognostic implications of preoperative anemia in urothelial carcinoma: A meta-analysis.

The prognostic significance of preoperative anemia (PA) has been identified in various malignancies. However, its predictive role in urothelial carcinoma (UC) remains controversial. The aim of this study was to investigate the prognostic value of PA in UC patients. We performed a meta-analysis of the association between PA and survival outcome in UC patients. Electronic databases were searched up to June 30, 2016. Study characteristics and prognostic data were extracted from each included study. Cancer-specific survival (CSS), recurrence-free survival (RFS), and overall survival (OS) were pooled using hazard ratio (HR) with corresponding 95% confidence intervals (CI). Herein, 12 studies comprising 3815 patients were included in the meta-analysis. There were 1593 (41.76%) patients in the PA group and 2222 (58.24%) in the control group. The overall pooled HRs of PA for CSS, RFS, and OS were significant at 2.21, (95% CI: 1.83-2.65, Pheterogeneity = 0.49, I2 = 0%), 1.87 (95% CI: 1.59-2.20, Pheterogeneity = 0.22, I2 = 28%), and 2.04(95% CI: 1.76-2.37, Pheterogeneity = 0.36, I2 = 9%) respectively. Stratified analyses indicated that PA was a predictor of poor prognosis based on ethnicity, sample size, tumor T stage, G grade, lymphovascular invasion (LVI), concomitant carcinoma in situ (CIS), and follow-up values. Our findings show that PA has negative prognostic effects on the survival outcome (CSS, RFS, and OS) in UC patients and can serve as a useful and cost-effective marker to aid prognosis prediction.

Prognostic impact of preoperative anemia on non-muscle-invasive bladder carcinoma treated with GreenLight laser vaporization.

In this study, we aimed to evaluate the impact of preoperative anemia (PA) on oncological outcomes among patients with non-muscle-invasive bladder cancer (NMIBC) treated with GreenLight laser vaporization of bladder tumor (PV-BT). Between January 2010 and December 2015, 407 patients with NMIBC who underwent PV-BT surgery were stratified into normal and anemia groups based on the World Health Organization classification (anemia cutoff value: hemoglobin level, <13.0 m g/dL in men and <12.0 mg/dL in women). The Student's t test and chi-square test were performed to assess the effects of PA on clinical and pathological characteristics of patients with NMIBC. The Kaplan-Meier method was used to investigate the influence of PA on oncological survival outcomes. Before PV-BT, 139 patients (34.2%) were anemic. No significant differences in age, sex, smoking habit, tumor size, focality, grade, and stage were found between the anemia and normal groups. At a median follow-up period of 32.5 months (range, 8-60 months), 74 patients (18.2%) had urothelial recurrence, 30 (7.4%) died from any cause, and 21 (5.2%) died from bladder cancer. In the Kaplan-Meier analysis, preoperative anemia was significantly associated with decreased cancer-specific survival (CSS) and overall survival (OS) of the patients with NMIBC. However, recurrence-free survival (RFS) showed no statistically significant difference between the PA and normal groups. The preoperative anemic patients with NMIBC who underwent PV-BT surgery had worse CSS and OS. PA can be a useful and cost-effective prognostic marker in the clinical practice for NMIBC treatment.

Magnetic resonance diffusion tensor imaging of optic nerve and optic radiation in healthy adults at 3T.

AIM: To investigate the diffusion characteristics of water of optic nerve and optic radiation in healthy adults and its related factors by diffusion tensor imaging (DTI) at 3T. METHODS: A total of 107 healthy volunteers performed head conventional MRI and bilateral optic nerve and optic radiation DTI. The primary data of DTI was processed by post-processing software of DTI studio 2.3, obtaining fractional anisotropy value, mean diffusivity value, principal engine value, orthogonal engine value by measuring, and analyzed by the SPSS13.0 statistical software. RESULTS: The bilateral optic nerve and optic radiation fibers presented green color in directional encoded color (DEC) maps and presented high signal in fractional anisotropy (FA) maps. The FA value of the left optic nerve was 0.598±0.069 and the right was 0.593±0.065; the mean diffusivity (MD) value of the left optic nerve was (1.324±0.349)×10(-3)mm(2)/s and the right was (1.312±0.350)×10(-3)mm(2)/s; the principal engine value (λ‖) of the left optic nerve was (2.297±0.522)×10(-3)mm(2)/s and the right was (2.277±0.526)×10(-3)mm(2)/s; the orthogonal engine value (λ⊥) of the left optic nerve was (0.838±0.285)×10(-3)mm(2)/s and the right was (0.830±0.280)×10(-3)mm(2)/s; the FA value of the left optic radiation was 0.636±0.057 and the right was 0.628±0.056; the mean diffusivity (MD) value of the left optic radiation was (0.907±0.103)×10(-3)mm(2)/s and the right was (0.889±0.125)×10(-3)mm(2)/s; the principal eigenvalue (λ‖) of the left optic radiation was (1.655±0.210)×10(-3)mm(2)/s and the right was (1.614±0.171)×10(-3)mm(2)/s; the orthogonal enginvalue (λ⊥) of the left optic radiation was (0.531±0.103)×10(-3)mm(2)/s and the right was (0.524±0.152)×10(-3)mm(2)/s. There was no obvious difference between the FA, MD, λ‖, λ⊥ of the bilateral optic radiation and the bilateral optic nerve (P>0.05) and no obvious difference between male and female group. The FA, MD, λ‖, λ⊥ of the bilateral optic radiation and the bilateral optic nerve had no obvious correlations to the age. CONCLUSION: DTI is sensitive to the optic nerve and radiation and the relevant DTI parameters of the optic nerve and radiation are established preliminarily in this study.