White Matter Hyperintensities after Five-Year Follow-Up and a Cross-Sectional FA Decrease in Bipolar I and Major Depressive Patients.

INTRODUCTION: An increase in brain white matter hyperintensities (WMHs) and a decrease in white matter fractional anisotrophy (FA) have been detected in bipolar I (BPI), II (BPII), and major depressive disorder (MDD) patients. Their relationship, and differences in diagnostic groups are obscure. Longitudinal studies are rare. OBJECTIVE: After 5-year follow-up, we evaluated WMHs in BPI, BPII, and MDD patients as compared with controls, and studied the effects of clinical variables. We also explored the associations of clinical variables with cross-sectional whole brain FA. METHODS: Eight BPI, 8 BPII, 6 MDD patients, and 19 controls participated in magnetic resonance imaging at baseline and follow-up. Diffusion weighted imaging was included at follow-up. WMHs were rated by the Coffey scale, and a tract-based spatial statistics method was used for diffusion data. The general linear model, ANOVA, Fisher's exact, Wilcoxon sign, and Kruskal-Wallis tests were used for statistical analyses. RESULTS: Periventricular WMHs were increased in BPI patients (p = 0.047) and associated with the duration of disorder and lifetime occurrence of substance use disorder (p = 0.018). FA decrease was found in the corpus callosum of BPI patients (p < 0.01). MDD patients showed FA decrease in the right cerebellar middle peduncle (RCMP) (p < 0.01). In BPI patients, the duration of disorder associated with FA increase in RCMP (p < 0.05). No FA decrease was detected in patients with WMHs as compared with those without. CONCLUSIONS: Preceding illness burden associated modestly with WMHs, and FA increase in RCMP in BPI patients. MDD patients had FA decrease in RCMP. No association with FA decrease and WMHs was found.

Location of gliomas in relation to mobile telephone use: a case-case and case-specular analysis.

The energy absorbed from the radio-frequency fields of mobile telephones depends strongly on distance from the source. The authors' objective in this study was to evaluate whether gliomas occur preferentially in the areas of the brain having the highest radio-frequency exposure. The authors used 2 approaches: In a case-case analysis, tumor locations were compared with varying exposure levels; in a case-specular analysis, a hypothetical reference location was assigned for each glioma, and the distances from the actual and specular locations to the handset were compared. The study included 888 gliomas from 7 European countries (2000-2004), with tumor midpoints defined on a 3-dimensional grid based on radiologic images. The case-case analyses were carried out using unconditional logistic regression, whereas in the case-specular analysis, conditional logistic regression was used. In the case-case analyses, tumors were located closest to the source of exposure among never-regular and contralateral users, but not statistically significantly. In the case-specular analysis, the mean distances between exposure source and location were similar for cases and speculars. These results do not suggest that gliomas in mobile phone users are preferentially located in the parts of the brain with the highest radio-frequency fields from mobile phones.

[Brain imaging of patients with memory disorders]. / Muistipotilaan aivojen kuvantaminen.

Indications for brain imaging include potentially treatable intracranial causes (e.g. normal-pressure hydrocephalus, tumors, subdural hematoma) and especially characteristic features of memory disorders and differential diagnostics of such conditions. Since the primary structural changes in the most common progressive memory disorder, Alzheimer's disease, are seen in the inner temporal lobe, appropriate imaging of these structures is essential in early diagnosis.

Major depressive disorder and white matter abnormalities: a diffusion tensor imaging study with tract-based spatial statistics.

BACKGROUND: A few diffusion tensor imaging (DTI) studies have shown abnormalities in areas of white matter tracts involved in mood regulation in geriatric depressive patients, using a region-of-interest technique. A voxel-based morphometry DTI study of young depressive patients reported similar results. In this study, we explored the structure of the white matter of the whole brain with DTI in middle-aged major depressive disorder (MDD) patients, using novel tract-based spatial statistics. METHODS: Sixteen MDD patients and 20 controls underwent DTI. An automated tract-based spatial method (TBSS) was used to analyze the scans. RESULTS: Compared with controls, the MDD patients showed a trend for lower values of fractional anisotropy (FA) in the left sagittal stratum, and suggestive decreased FA in the right cingulate cortex and posterior body of corpus callosum. Regressing out the duration and severity of disorder in the model did not change the finding in the sagittal stratum, but dissipated the decrease of FA in latter regions. LIMITATIONS: Possibly by reason of a relatively small study sample for a TBSS, the results are suggestive, and should be replicated in further studies. CONCLUSIONS: A novel observer-independent DTI method showed decreased FA in the middle-aged MDD patients in white matter regions that have previously connected to the emotional regulation. Lower FA might imply underlying structural abnormalities that contribute to the dysfunction detected in the limbic-cortical network of depressive patients.

Mobile phone use and location of glioma: a case-case analysis.

We assessed a new approach for evaluating the glioma risk among users of mobile phones to focus on the part of the brain most heavily exposed to radiofrequency electromagnetic fields from mobile phones. The tumor midpoint was defined from radiological imaging. A case-case analysis with 99 gliomas was performed using logistic regression. The exposed cases were those with the tumor mid-point within 4.6 cm from the line between the mouth and the external meatus of the ear, representing the most likely location of the mobile phone (the source of exposure). Alternative analyses based on various indicators of mobile phone use as the outcome were also carried out. The majority of cases were regular mobile phone users. A slightly higher proportion of gliomas among mobile phone users than non-users occurred within 4.6 cm from the presumed location of the mobile phone (28% vs. 14%). Modestly elevated odds ratios were observed for several indicators of mobile phone use, but without an exposure gradient. The highest odds ratios were found for contralateral and short-term use. Our results, though limited by the small sample size, demonstrate that detailed information on tumor location allows evaluation of the risk related to the most heavily exposed part of the brain, representing direct evaluation of the possible local carcinogenic effects of the radiofrequency fields. However, field strength varies between users and over time also within a given anatomic site, due to the output power of the phone. Collaborative analysis of a larger sample is planned.

Magnetic resonance imaging in occupational chronic solvent encephalopathy.

PURPOSE: The aim of this study was to characterize the magnetic resonance imaging (MRI) findings in chronic solvent encephalopathy (CSE) patients and to study whether the findings are associated with solvent exposure indices. METHODS: The brain MRI scans of 71 CSE patients were independently re-evaluated and rated by two experienced neuroradiologists. All the work tasks were analyzed and the chemical composition of lifetime exposure was categorized. RESULTS: The MRI scans of 27/71 CSE patients (38%) were classified as abnormal. Brain atrophy in any brain area was found in 17/71 CSE patients (24%). Abnormal white matter hyperintensities (WMH) were found in 20/71 CSE patients (28%). Cerebral and cerebellar brain atrophy was associated with the duration of exposure in years, and vermian atrophy was associated with alcohol consumption. Periventricular and brainstem WMH were related to age. CONCLUSIONS: Slight brain atrophy is associated with CSE and there is a correlation between brain atrophy and the duration of exposure in years. However, all the MRI findings in CSE are non-specific and thus MRI is useful mainly in the differential diagnosis of CSE.

White matter lesions are related to impaired instrumental activities of daily living poststroke.

BACKGROUND: White matter lesions (WMLs) are frequent in elderly people, and have been associated with impaired activities of daily living (ADL) and cognitive decline. We sought to examine the role of WMLs and their extent, in regard to basic ADL, instrumental ADL (IADL), and cognitive functions, in a large well-defined cohort examined 3 months after an ischemic stroke. METHODS: The study group included 395 of 486 consecutive patients aged 55 to 85 years who, 3 months after an ischemic stroke, completed a neuropsychological test battery and magnetic resonance imaging, and structured medical, neurological, and laboratory evaluations; assessment included an interview with a knowledgeable informant. RESULTS: The patients with the most severe WMLs (n = 213) were older, in comparison with those with moderate (n = 71) or mild/no (n = 111) WMLs. These patients also more often had Diagnostic and Statistical Manual of Mental Disorders, Third Edition dementia; had a lower Mini Mental Status score; were more often women; more often had impaired immediate and delayed memory performance, executive dysfunction, and impaired basic ADL and IADL functions; and had more infarcts and cortical or central atrophy in magnetic resonance imaging. However, there were no significant differences among the 3 groups in stroke severity measured on the Scandinavian Stroke Scale, in stroke-related depression as measured by the Beck Depression Inventory, or in stroke type. According to multiple logistic regression analysis, higher age (odds ratio 1.067, 95% confidence interval 1.036-1.01) and impaired IADL (odds ratio 0.852, 95% confidence interval 0.778-0.931) significantly correlated with severe WMLs. CONCLUSIONS: Although the degree of WMLs was not associated with stroke severity, it was associated with global cognitive function, impaired memory functions, executive dysfunction, sex, and impaired basic ADL. Age and IADL functions were independent correlates of severe WMLs.

Incidence of gliomas by anatomic location.

The anatomic location of a glioma influences prognosis and treatment options. The aim of our study was to describe the distribution of gliomas in different anatomic areas of the brain. A representative population-based sample of 331 adults with glioma was used for preliminary analyses. The anatomic locations for 89 patients from a single center were analyzed in more detail from radiologic imaging and recorded on a three-dimensional 1 x 1 x 1-cm grid. The age-standardized incidence rate of gliomas was 4.7 per 100,000 person-years. The most frequent subtypes were glioblastoma (47%) and grade II-III astrocytoma (23%), followed by oligodendroglioma and mixed glioma. The gliomas were located in the frontal lobe in 40% of the cases, temporal in 29%, parietal in 14%, and occipital lobe in 3%, with 14% in the deeper structures. The difference in distribution between lobes remained after adjustment for their tissue volume: the tumor:volume ratio was 4.5 for frontal, 4.8 for temporal, and 2.3 for parietal relative to the occipital lobe. The area with the densest occurrence was the anterior subcortical brain. Statistically significant spatial clustering was found in the three-dimensional analysis. No differences in location were found among glioblastoma, diffuse astrocytoma, and oligodendroglioma. Our results demonstrate considerable heterogeneity in the anatomic distribution of gliomas within the brain.

Depression-executive dysfunction syndrome in stroke patients.

OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. METHODS: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options.

Temozolomide treatment in glioma--experiences in two university hospitals in Finland.

Thirty-two patients with relapsing glioma were treated with temozolomide in two university hospitals in Finland. One patient (3%) had complete response and 9 (28%) partial response, with 8 patients (25%) showing stable disease. Median progression-free survival for these 18 patients (56%) was 7 months (range 2-11+). The remaining either had progressive disease (25%) or only clinical evaluation (19%). Karnofsky score improved in 34% of patients and decreased in 3%. Symptoms were alleviated in 44% and deteriorated in 9%. Grade 3-4 toxicity was detected in 9% of the patients. Only 4% of the days in treatment were spent in hospital. An average 1.8 neuroradiological investigations, 6.9 laboratory visits, and 5.3 visits to the oncologist were made. This study confirms that temozolomide has positive effects on the outcome of often heavily pretreated glioma patients. High drug costs are compensated by prolonged home care and even the possibility to maintain working capacity.

Clinical features of MRI-defined subcortical vascular disease.

BACKGROUND AND PURPOSE: Vascular cognitive impairment and vascular dementia are now seen to extend much beyond the traditional multi-infarct dementia.A more homogeneous subtype is the subcortical ischemic vascular disease (SIVD). We applied magnetic resonance imaging (MRI) criteria based on research criteria for SIVD in a large cohort of patients with ischemic stroke. We compared clinical features of patients with SIVD and patients with other stroke type. SUBJECT AND METHODS: The study group comprised 337 of 486 consecutive patients aged 55 to 85 years who 3 months after ischemic stroke completed a comprehensive neuropsychological test battery and MRI, including structured medical, neurologic, and laboratory evaluations; clinical mental status examination; interview of a knowledgeable informant; detailed history of risk factors; and evaluation of stroke type, localization, and syndrome. RESULTS: Patients with SIVD (n = 86) more often had a history of progressive cognitive decline (22.8% vs. 6.9%, P = 0.0002), walking disorder before stroke (27.9% vs. 2.0%, P = 0.02), and urinary difficulties (12.8% vs. 5.6%, P = 0.028) in comparison with patients with other stroke type (n = 251). Of the study population, 107 (31.8%) had DSM-III dementia. The patients with SIVD more often had DSM-III dementia (40.7% vs. 28.7%, P = 0.04), had less severe stroke as measured by Scandinavian Stroke Scale (56.6 vs. 55.1, P = 0.03), were more dependent in activities of daily living (ADL) functions as measured by FAQ scale (8.9 vs. 5.4, P = 0.001), were more dependent in instrumental activities of daily living (IADL) functions as measured by the Lawton scale (5.5 vs. 6.3, P = 0.01), and were more depressed as measured by the Beck Depression Inventory (11.8 vs. 8.4, P = 0.0003) poststroke than the patients without SIVD. The main cognitive domain that differentiated the patients with SIVD from those without was executive dysfunction (51.2% vs. 38.7%, P = 0.04). According to multiple regression model, apractic-atactic gait disorder (odds ratio 2.82, 95% confidence interval 1.21-6.53), ADL functions (odds ratio 1.04, 95% confidence interval 1.01-1.08), and the Beck Depression Inventory (odds ratio 1.05, 95% confidence interval 1.02-1.09) related to SIVD. CONCLUSIONS: The most significant clinical features of MRI-defined SIVD were found to be apractic-atactic gait, impaired ADL functions, and depression.