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Journal Article 2013; 34(2): 162-171 PubMed PMID: 23645314 Citation  Keywords:  Adult, Analysis of Variance, Brain:pathology, Brain Mapping:methods, Cognitive Therapy:methods, Electroencephalography, Female, Humans, Imaging, Three-Dimensional:methods, Male, Middle Aged, Panic Disorder:diagnosis, Psychiatric Status Rating Scales, Trea.   

BACKGROUND: Standardized low-resolution electromagnetic tomography (sLORETA) is a new quantitative EEG method for determining distribution of neuronal electrical activity in the form of three-dimensional images of current density of the cerebral cortex. Unlike standard quantitative EEG, it allows noninvasive and detailed localization of neuronal generators responsible for surface EEG with zero localization error. The study aimed at finding electrotomographic differences between patients with panic disorder who respond well to cognitive behavioral therapy (CBT) and those with an inadequate response and to determine factors predicting a response to treatment.

METHODS: The study comprised 24 patients diagnosed with panic disorder with or without agoraphobia (ICD-10 F41.0). The severity of symptoms was measured with the Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI), Sheehan Anxiety Scale, subjective and objective Clinical Global Impression (CGI) and Dissociative Experiences Scale (DES). Additionally, quality of life was evaluated using the Q-LES-Q questionnaire. Based on final BAI score decreases by 25%, the patients were classified into two groups - responders and non-responders. 21-channel EEGs were recorded at baseline and after completion of therapy. Power spectra and intracortical tomography were computed by sLORETA in seven frequency bands and compared between (responders vs. non-responders) and within (pre- vs. post-treatment) groups.

RESULTS: There were no differences between responders and non-responders with respect to age, gender and baseline disorder symptomatology. Statistical analysis of sLORETA values demonstrated no significant inter-group differences in the pretreatment current density distribution. After treatment, only responders showed a significant decrease of alpha-2 sources (p<0.05) in the occipital lobes and cuneus and a statistical trend for increased beta-3 sources (p<0.10) in the posterior cingulate. In non-responders, there were no statistically significant changes in sLORETA findings following therapy.

CONCLUSIONS: The study failed to use pretreatment sLORETA in the prediction of therapeutic response in patients with panic disorder. However, we clearly demonstrated that only treatment response was associated with significant changes of electric neuronal activity. An analysis of demographic data suggested that duration of the disease, age, level of dissociation and employment may be considered as factors influencing the response....

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Journal Article 2010; 31(1): 73-86 PubMed PMID: 20150883 Citation  Keywords:  Adult, Brain Mapping, Cerebral Cortex:physiopathology, Dystonic Disorders:therapy, Female, Handwriting, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Models, Biological, Pilot Projects, Placebos, Radiation, Somatosensory Cortex:physiopathology, T.   

: Since the somatosensory system is believed to be affected in focal dystonia, we focused on the modulation of the primary somatosensory cortex (SI) induced by repetitive transcranial magnetic stimulation (rTMS) in order to improve symptoms of writer's cramp. Patients with writer's cramp (N=9 in the pilot study and N=11 in the advanced study) were treated with 30-minute 1 Hz real- or sham-rTMS of the SI cortex every day for 5 days. Before and after rTMS, 1.5 T fMRI was examined during simple hand movements. While in the pilot study the rTMS coil was navigated over the SI cortex with a maximum of blood oxygenation-level dependent (BOLD) signal induced by passive movement, patients in the advanced study had the coil above the postcentral sulcus. After real-rTMS, 4 pilot study patients and 10 advanced study patients experienced subjective and objective improvement in writing, while only minimal changes were observed after sham-rTMS. Patients involved in the active movement task exhibited a rTMS-induced BOLD signal increase bilaterally in the SI cortex, posterior parietal cortex and in the supplementary motor area (P<0.001 corrected). After sham-rTMS, no BOLD signal changes were observed. In conclusion, 1 Hz rTMS of the SI cortex can improve writer's cramp while increasing the cortical activity in both hemispheres. Handwriting improved in most patients, as well as the subjective benefit, and lasted for 2-3 weeks. The beneficial effects of rTMS paralleled the functional reorganization in the SI cortex and connected areas, reflecting the impact of somatosensory system on active motion control....

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Clinical Trial 2010; 31(1): 161-167 PubMed PMID: 20150864 Citation  Keywords:  Adult, Brain Mapping:methods, Cerebral Cortex:metabolism, Cystine:analogs & derivatives, Estrogen Replacement Therapy, Female, Humans, Hypothyroidism:diagnosis, Male, Neuropsychological Tests, Prognosis, Severity of Illness Index, Technetium:chemistry, Th.   

OBJECTIVE: The purpose of this study was to correlate hypothyroid-related symptomatology with regional cerebral blood flow (rCBF) during hypothyroidism.

MATERIALS AND METHODS: Nine thyroidectomized patients underwent neuropsychological testing and single photon emission computed tomography (SPECT) of their brains with technetium-99m (Tc-99m) ethyl cysteinate dimer (ECD), a lipophilic cerebral blood flow radiotracer, while hypothyroid, and again following thyroid hormone replacement. Neuropsychological test scores and TSH levels while hypothyroid were correlated with rCBF in hypothyroid-affected areas of the brain.

RESULTS: Correlations were found during hypothyroidism between the noted parameters and ECD radiotracer accumulation in the following respective regions, all of which demonstrated hypothyroid-related cerebral blood flow (CBF) aberrations: TSH and left middle occipital gyrus; psychomotor performance speed and left precentral gyrus; and depression and right middle frontal gyrus, left middle frontal gyrus, right insula, and left thalamus.

CONCLUSIONS: Severity of psychomotor impairment and depression, and TSH level during hypothyroidism appeared to correlate with CBF to brain regions associated with motor activity, mood and vision, respectively; and previously shown to manifest significantly altered rCBF during hypothyroidism....

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Journal Article 2009; 30(1): 119-124 PubMed PMID: 19300390 Citation  Keywords:  Adult, Brain Mapping, Case-Control Studies, Cerebrum:pathology, Depression:complications, Diabetes Mellitus:pathology, Diabetic Neuropathies:complications, Dominance, Cerebral:physiology, Evoked Potentials, Visual, Female, Humans, Male, Middle Aged, Psych.   

OBJECTIVES: The present study was undertaken in order to verify the hypothesis stating that patients with depression exhibit some abnormalities concerning a cerebral symmetry. For this purpose, an analysis of the relationship between the VEPs (Visual Evoked Potentials) results and the depressive symptoms intensification, as well interrelation between depressive and diabetic symptoms were performed.

MATERIAL AND METHODS: VEPs recordings were obtained from the two study groups (both aged 20-45 years), 20 healthy subjects and 32 diabetic patients with clinically documented depression. The VEPs examination was carried out using a computer system called STELLA (Stimulated Electroencephalogram on Line Analyzer).

RESULTS: VEPs examinations revealed a cerebral symmetry in the all control subjects and in 10 out of 32 diabetic patients with depressive disorders. It is noteworthy that 22 of 32 diabetic patients (68.8%) showed a hemispheric asymmetry in the VEPs recordings. Of 12 patients with a moderate depression, 10 showed the left cerebral laterality, and 2--the right laterality. In turn, all 10 patients with major depressive disorder (MDD) demonstrated in the VEPs recordings a significant cerebral laterality with the right hemisphere dominance.

CONCLUSIONS: The obtained results suggest that interhemispheric cerebral asymmetry might be considered a specific feature of depression, and, if this is a case, it could justify a conclusion that right hemisphere dominance could be a neurophysiological marker of MDD. It should be emphasized that intensification of the depressive symptoms has an unfavorable influence on course of diabetes mellitus, its self-control and severity of following complications....

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Clinical Trial 2007; 28(1): 53-59 PubMed PMID: 17277726 Citation  Keywords:  Adult, Brain Mapping, Case-Control Studies, Cognition:physiology, Female, Fluorodeoxyglucose F18, Hallucinations:diagnostic imaging, Humans, Male, Positron-Emission Tomography, Prefrontal Cortex:diagnostic imaging, Psychotic Disorders:diagnostic imaging, .   

OBJECTIVE: The aim of the study was to detect whether the abnormal regional brain activity correlates with auditory verbal hallucination-proneness (AVH) in a group of patients with schizophrenia and schizophrenia-related psychoses.

METHODS: 15 patients with prominent AVH (score for hallucination intensity--item 3 in the PANSS > or =4) and 15 control patients without AVH (item 3 PANSS score < or =2) underwent 18FDG positron emission tomography at rest.

RESULTS: SPM group analysis revealed an increased uptake of 18FDG in the right middle frontal gyrus (BA46) in subjects with high verbal hallucination score compared to non-hallucinating patients (p<0.001, uncorrected). Activation in BA46 positively correlated with the intensity of hallucinations (Spearman r=0.57; p<0.001).

CONCLUSIONS: The observed functional recruitment of the right prefrontal cortex in subjects with high hallucination score may reflect impairment in the integration of intended actions and sensory feedback resulting in misattribution of internal events to an external source. This mechanism may form the cognitive basis for AVH....

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Controlled Clinical Trial 2006; 27(5): 587-594 PubMed PMID: 17159818 Citation  Keywords:  Adolescent, Adult, Basal Metabolism, Brain:metabolism, Brain Mapping, Female, Fluorodeoxyglucose F18:metabolism, Frontal Lobe:metabolism, Humans, Male, Middle Aged, Positron-Emission Tomography:methods, Psychomotor Performance, Schizophrenia:metabolism, T.   

OBJECTIVES: With the aim to indicate the functional anatomical substrate of cognitive dysfunction in schizophrenia we evaluated the relationship between resting brain metabolism and performance on the Trail Making Test (TMT). As the prerequisite analysis we compared the performance in Part A and B of the TMT between schizophrenic patients and controls. Resting brain metabolism was investigated by (18)FDG positron emission tomography (PET) as the probe for the relative regional synaptic strength and density.

METHODS: (18)FDG PET data were analyzed by SPM99 with TMT A and B as the covariate (p< or =0.001).

RESULTS: Schizophrenic patients (N=42) had worse performance in both TMT A and B compared to controls (N=42). In schizophrenic subjects (18)FDG PET did not predict the performance on Part A (psychomotor speed) but predicted that for Part B (set-shifting and flexibility) of the TMT. The (18)FDG uptake in the superior, middle and inferior frontal gyruses bilaterally was associated with better performance in the TMT B. The negative covariation between 18FDG uptake and time spent in the TMT B was detected in the temporal and parietal cortices, pre- and postcentral gyruses, precuneus limbic regions (anterior cingulate, uncus) and the pons.

CONCLUSIONS: Our data indicate that hypometabolism in the frontal lobes and hypermetabolism in the temporo-parieto-limbic regions is the neurobiological basis for deficient TMT B performance in schizophrenia....

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Clinical Trial, Phase I 2005; 26(6): 685-689 PubMed PMID: 16380684 Citation  Keywords:  Adult, Antipsychotic Agents:therapeutic use, Benzodiazepines:therapeutic use, Brain Mapping, Cerebrovascular Circulation:drug effects, Cysteine:analogs & derivatives, Frontal Lobe:blood supply, Humans, Male, Middle Aged, Organotechnetium Compounds, Psychi.   

OBJECTIVES: Altered regional cerebral blood flow (r-CBF) is mentioned as one of possible etiological factors or as a consequence of schizophrenia. Perfusion scintigraphic brain studies with SPECT (Single Photon Emission Computed Tomography) and PET (Positron Emission Tomography) can detect areas of the brain with altered perfusion during the disease. Conflicting data exist on follow-up after treatment. The aim of our study was to evaluate r-CBF in acute first-episode schizophrenia and early effect of antipsychotic drugs on r-CBF.

DESIGN AND SETTING: Clinical criteria for schizophrenia were met according to International Classification of Diseases-10th Edition (ICD-10). Psychic status and severity of the disease in each patient were evaluated with psychiatric interview, Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression (CGI) on the same day as the scintigraphic study. Brain perfusion SPECT was performed 20 minutes after 99mTc-ECD application. R-CBF was measured in 9 first-episode schizophrenic male patients 2-7 (median 6) days after the beginning of antipsychotic treatment and 8-15 (median 9) weeks later. Semiquantitative analysis of r-CBF was performed with cerebellum as the reference region. R-CBF was evaluated for 12 regions in each study.

RESULTS: Decrease in perfusion in comparison to cerebellum was detected in left (90%) and right (93%) frontal lobes. Increase in perfusion between the first (t1) and the second (t2) investigation was significant (p<0.05) for both frontal regions (left 94%, right 97%). Significant decrease in PANSS (p<0.05) and CGI (p<0.001) scores was noted and correlated well with the increase of r-CBF.

CONCLUSIONS: Our findings implicate that patients with first-episode schizophrenia have significant left hypoperfusion relative to the right in dorsolateral frontal lobes. Increased blood flow was observed bilaterally in dorsolateral frontal lobes after 10 weeks of antipsychotic medication. Significant amelioration of r-CBF correlated with clinical improvement....

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Clinical Trial 2004; 25(5): 340-348 PubMed PMID: 15580167 Citation  Keywords:  Adult, Antidepressive Agents:therapeutic use, Brain Mapping, Cerebral Cortex:diagnostic imaging, Cognitive Therapy, Female, Fluorodeoxyglucose F18, Functional Laterality, Humans, Male, Neuropsychological Tests, Panic Disorder:diagnostic imaging, Positron-.   

BACKGROUND: The goal of our study was to identify brain structures in patients with panic disorder (PD) that show changes in 18FDG PET during the treatment with cognitive behavioral therapy (CBT) or antidepressants.

METHOD: Twelve patients suffering from panic disorder were studied with [18F]-2-fluoro-deoxyglucose positron emission tomography (18FDG PET) scanning during resting state (condition of random episodic silent thinking, REST). After PET examination patients were randomly assigned to either cognitive behavioral treatment group (6 patients) or antidepressants treatment group (6 patients). After a 3 month period 18FDG PET examination was repeated in both groups. Psychopathology was assessed using the rating scales HAMA, CGI and Panic Disorder Severity Scale (PDSS). Data were analysed using software for statistical parametric mapping (SPM99).

RESULTS: The scores of psychopathology rating scales (CGI, HAMA, PDSS) decreased in both groups. Changes of 18FDG uptake in the pharmacotherapy group: decreases were found in the a priori hypothesized regions in the right hemisphere, in the superior, middle, medial and inferior frontal gyrus, superior and middle temporal gyrus, and increases were detected in the a priori hypothesized regions, mainly in the left hemisphere in medial and middle frontal gyrus, superior, middle and transverse temporal gyrus. Changes of 18FDG uptake in the CBT group: decreases were found in the a priori hypothesized regions of the right hemisphere in the inferior temporal gyrus, superior and inferior frontal gyrus, and increases were detected in the a priori hypothesized region, mostly in the left hemisphere: inferior frontal gyrus, middle temporal gyrus and insula. We did not detect changes in 18FDG uptake in the limbic region (hippocampus, parahippocampal gyrus and amygdala).

CONCLUSIONS: Changes in brain metabolism (18FDG uptake) after the treatment either with CBT or with antidepressants were similar in number of brain areas, with prominent right-left difference. This is in concordance with the asymmetry of brain activity noted in patients with PD according to previous PET (and SPECT) studies....

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