Normal Metabolic Levels in Prefrontal Cortex in Euthymic Bipolar I Patients with and without Suicide Attempts.

Introduction/Objective. Evidence suggests that the prefrontal cortex has been implicated in the pathophysiology of bipolar disorder (BD), but few neurochemical studies have evaluated this region in bipolar patients and there is no information from BD suicide attempters using Proton Magnetic Resonance Spectroscopy (H(+)MRS). The objective was to evaluate the metabolic function of the medial orbital frontal cortex in euthymic BD type I suicide and nonsuicide attempters compared to healthy subjects by H(+)MRS. Methods. 40 euthymic bipolar I outpatients, 19 without and 21 with history of suicide attempt, and 22 healthy subjects were interviewed using the Structured Clinical Interview with the DSM-IV axis I, the Hamilton Depression Rating Scale, the Young Mania Rating Scale, and the Barratt Impulsiveness Scale-11 and underwent H(+)MRS. Results. We did not find any metabolic abnormality in medial orbital frontal regions of suicide and nonsuicide BD patients and BD patients as a group compared to healthy subjects. Conclusions. The combined chronic use of psychotropic drugs with neuroprotective or neurotrophic effects leading to a euthymic state for longer periods of time may improve neurometabolic function, at least measured by H(+)MRS, even in suicide attempters. Besides, these results may implicate mood dependent alterations in brain metabolic activity. However, more studies with larger sample sizes of this heterogeneous disorder are warranted to clarify these data.

Diffusion tensor imaging metrics in diagnosis of HTLV-1-associated myelopathy.

OBJECTIVE: In the diagnosis of HTLV-1-associated myelopathy (HAM), while magnetic resonance imaging (MRI) is essential to exclude other diseases, its power is limited regarding HAM diagnosis, as only 30% of affected patients present with spinal cord atrophy. Diffusion tensor imaging (DTI) may enable the detection of damage in the white matter microstructure. Here, we quantitatively assess spinal cord damage using DTI and evaluate conventional MRI parameters of the spinal cord in HTLV-1-infected individuals. METHODS: This cross-sectional study involved 33 HTLV-1 carriers, 28 patients with definite-HAM, and 11 seronegative healthy subjects (HS). Region-of-interest (ROI)-based fractional anisotropy (FA) and mean diffusivity (MD) measurements were performed in the upper thoracic and lumbar regions of the spinal cord. Thoracic index was defined as 1/ (anteroposterior diameter × transverse diameter) measured at the fifth 5th vertebral level. Receiver operating characteristic (ROC) curve analysis was used to determine optimal cutoff FA, MD, and thoracic index values. RESULTS: Spinal cord atrophy was observed in 15 (53.6%) patients with definite-HAM. The area under the ROC curve in the thoracic spinal cord was 0.824 (95% CI, 0.716-0.932), 0.839 (95% CI: 0.736-0.942), and 0.838 (95% CI: 0.728-0.949) for FA, MD, and the thoracic index, respectively. Lower FA and higher MD values were observed in the definite-HAM group compared to HTLV-1 carriers and HS at the T5 vertebral level (p < 0.01). INTERPRETATION: Complementary to conventional MRI, DTI analysis of the spinal cord and thoracic index determination can offer additional insight that may prove useful in the diagnosis of HAM.

Prefrontal gray matter volume in adults bipolar I outpatients is associated with history of suicide attempts?

ABSTRACT Background: Patients with Bipolar Disorder (BD) have the highest lifetime risk for suicidal behavior (SB) compared to other psychiatric disorders. Neuroimaging research provides evidence of some structural and functional abnormalities in the brain of BD suicide attempters (SA), but interpretation of these findings may represent a number of features. Objective: The purpose of this study was to evaluate the volume of the prefrontal cortex in euthymic BD type I outpatients, with and without history of SA. Methods: 36 euthymic BD I outpatients (18 with and 18 without suicide attempt history) were underwent structural MRI and total and regional gray matter volumes were assessed and compared with 22 healthy controls (HC). Results: We did not found any differences in all areas between suicidal and non-suicidal BD I patients and BD patients as a group compared to HC as well. Discussion: our findings suggest that can be a different subgroups of patients in relation to prefrontal cortex volumes according to some clinical and socio-demographic caractheristics, such as number of previous episodes and continuous use of medical psychotropic drugs that may induce neuroplasticity phenomena, which restore cerebral volume and possibly can lead to long-term euthymia state.