Amplitude of low-frequency fluctuations of resting-state functional MRI in colorectal cancer patients with depression / 中华肿瘤杂志

Objective@#To investigate the alterations of the cerebral resting-state spontaneous neural activity in colorectal cancer patients with depressive symptoms.@*Methods@#Thirty-three colorectal cancer patients (patient group) with depression and 43 healthy subjects (control group) underwent the resting state functional magnetic resonance imaging (rs-fMRI). The amplitude of low-frequency fluctuations (ALFF) and fractional ALFF (fALFF) were calculated. Two independent samples t test were used to compare the ALFF and fALFF values between two groups by DPABI software, and then correlation analysis was performed between ALFF and fALFF with statistical significance and Patient Health Questionnaire (PHQ-9) scores and Generalized Anxiety Disorder (GAD-7) scores.@*Results@#Compared with the control group, the patient group showed significantly lower ALFF and fALFF values in the bilateral precuneus, calcarine gyrus, lingual gyrus, left cuneus, superior, middle, inferior occipital gyrus and right fusiform gyrus (t=-5.730, P<0.05; t=-4.872, P<0.05). There were no significant correlations between the ALFF and fALFF values in these regions and PHQ-9 or GAD-7 scores (P>0.05).@*Conclusion@#Spontaneous decrease of neural activity in occipital and parietal lobes exists in colorectal cancer patients with depression at resting-sate, which may be a potential neurobiological marker.

Analysis of microstructure and blood perfusion in thalamus and basal ganglia in patients with untreated depressive disorder / 中国医学影像技术

Objective To investigate the changes of microstructure and blood perfusion of thalamus and basal ganglia in patients with untreated depressive disorder using diffusion kurtosis imaging (DKI) and three-dimensional arterial spin labeling (3D ASL) perfusion imaging.Methods Totally 21 untreated patients with depressive disorder (disease group) and 32 healthy volunteers (control group) underwent DKI,3D ASL and routine MR scanning were enrolled.DKI parameters (mean kurtosis [MK],axial kurtosis [Ka],radial kurtosis [Kr],fractional anisotropy [FA],mean diffusivity [MD],axial diffusivity [Da] and radial diffusivity [Dr]) and 3D ASL parameters (cerebral blood flow [CBF]) of bilateral heads of caudate nucleus,thalamus and putamens were measured and compared between the 2 groups.Results Compared with control group,Ka of left caudate head in disease group was significantly higher,while Kr was significantly lower (both P＜ 0.05).Ka of right putamens in disease group was significantly higher than that in control group (P＜0.05).Compared with control group,CBF of left caudate head and bilateral putamens decreased significantly in disease group (all P＜0.05).Conclusion Untreated depressed patients show abnormal DKI parameters and blood perfusion in basal ganglia,which indicating that microstructure integrity is impaired and blood perfusion decreases.The abnormalities in basal ganglia microstructure and blood perfusion may serve as one of the neuroimaging features of depressive disorders.

Microstructural Abnormalities of Basal Ganglia and Thalamus in Bipolar and Unipolar Disorders: A Diffusion Kurtosis and Perfusion Imaging Study

OBJECTIVE: Bipolar disorder (BD) is often misdiagnosed as unipolar depression (UD), leading to mistreatment and poor clinical outcomes. However, little is known about the similarities and differences in subcorticalgray matter regions between BD and UD. METHODS: Thirty-five BD patients, 30 UD patients and 40 healthy controls underwent diffusional kurtosis imaging (DKI) and three dimensional arterial spin labeling (3D ASL). The parameters including mean kurtosis (MK), axial kurtosis (Ka), radial kurtosis (Kr), fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da), radial diffusivity (Dr) and cerebral blood flow (CBF) were measured by using regions-of-interest analysis in the caudate, putamen and thalamus of the subcortical gray matter regions. RESULTS: UD exhibited differences from controls for DKI measures and CBF in the left putamen and caudate. BD showed differences from controls for DKI measures in the left caudate. Additionally, BD showed lower Ka in right putamen, higher MD in right caudate compared with UD. Receiver operating characteristic analysis revealed the Kr of left caudate had the highest predictive power for distinguishing UD from controls. CONCLUSION: The two disorders may have overlaps in microstructural abnormality in basal ganglia. The change of caudate may serve as a potential biomarker for UD.