[Silicosis]. / Silicose.

BACKGROUND: Silicosis is a potentially severe but preventable occupational lung disease caused by inhalation of silica particles. There is a wide application in the usage of silica especially in lesser known industries. This disease has yet not been eradicated due to insufficient application of protective measures. CASE DESCRIPTION: A 57-year-old patient presents to the pulmonary outpatient clinic with progressive dyspnea d'effort. The professional history states that he worked as a sandblaster 10 years ago. The accompanying protective measures were not properly followed by the patient at the time. The CT chest showed a nodular interstitial lung disease and silica particles were detected in the bronchial lavage conforming the diagnosis of silicosis. CONCLUSION: Early detection of silicosis is essential to prevent further lung damage and silicosis associated complications. The occupational history and radiological diagnostics are essential to confirm the diagnosis. There is no specific treatment for silicosis. Therefore prevention is better than cure.

COVID-19 on Chest Radiographs: A Multireader Evaluation of an Artificial Intelligence System.

Background Chest radiography may play an important role in triage for coronavirus disease 2019 (COVID-19), particularly in low-resource settings. Purpose To evaluate the performance of an artificial intelligence (AI) system for detection of COVID-19 pneumonia on chest radiographs. Materials and Methods An AI system (CAD4COVID-XRay) was trained on 24 678 chest radiographs, including 1540 used only for validation while training. The test set consisted of a set of continuously acquired chest radiographs (n = 454) obtained in patients suspected of having COVID-19 pneumonia between March 4 and April 6, 2020, at one center (223 patients with positive reverse transcription polymerase chain reaction [RT-PCR] results, 231 with negative RT-PCR results). Radiographs were independently analyzed by six readers and by the AI system. Diagnostic performance was analyzed with the receiver operating characteristic curve. Results For the test set, the mean age of patients was 67 years ± 14.4 (standard deviation) (56% male). With RT-PCR test results as the reference standard, the AI system correctly classified chest radiographs as COVID-19 pneumonia with an area under the receiver operating characteristic curve of 0.81. The system significantly outperformed each reader (P < .001 using the McNemar test) at their highest possible sensitivities. At their lowest sensitivities, only one reader significantly outperformed the AI system (P = .04). Conclusion The performance of an artificial intelligence system in the detection of coronavirus disease 2019 on chest radiographs was comparable with that of six independent readers. © RSNA, 2020.

Loss of entorhinal cortex and hippocampal volumes compared to whole brain volume in normal aging: the SMART-Medea study.

In non-demented elderly age-related decline in hippocampal volume has often been observed, but it is not clear if this loss is disproportionate relative to other brain tissue. Few studies examined age-related volume loss of the entorhinal cortex. We investigated the association of age with hippocampal and entorhinal cortex (ERC) volumes in a large sample of middle-aged and older persons without dementia. Within the SMART-Medea study, cross-sectional analyses were performed in 453 non-demented subjects (mean age 62±9 years, 81% male) with a history of arterial disease. Hippocampal and ERC volumes were assessed by manual segmentation on three-dimensional fast field-echo sequence T1-weighted magnetic resonance images. Automated segmentation was used to quantify volumes of BV and ICV. Hippocampal and ERC volumes were divided by intracranial volume (ICV) as well as total brain volume (BV) to determine whether age-related differences were disproportionate relative to other brain tissue. Total crude hippocampal volume was 5.96±0.7 ml and total crude ERC volume was 0.34±0.06 ml. Linear regression analyses adjusted for sex showed that with increasing age, hippocampal volume divided by ICV decreased (B per year older=-0.01 ml; 95% CI -0.02 to -0.004). However, no age-related decline in hippocampal volume relative to BV was observed (B per year older=0.005 ml; 95% CI -0.002 to 0.01). No age-related decline in ERC volume relative to ICV or BV was observed. In this population of nondemented patients with a history of vascular disease no age-related decline in entorhinal cortex volume was observed and although hippocampal volume decreased with age, it was not disproportionate relative to total brain volume.

Depression, hypothalamic pituitary adrenal axis, and hippocampal and entorhinal cortex volumes--the SMART Medea study.

BACKGROUND: Structural brain changes have often been found in major depressive disorder (MDD), and it is thought that hypothalamic-pituitary-adrenal (HPA) axis hyperactivity may explain this relation. We investigated the association of MDD and history of depression with hippocampal and entorhinal cortex volumes and whether HPA axis activity explained this association. METHODS: In 636 participants with a history of atherosclerotic disease (mean age 62 ± 9 years, 81% male) from the second Manifestation of ARTerial disease-Memory depression and aging (SMART-Medea) study, a 12-month diagnosis of MDD and history of depression were assessed. Age of first depressive episode was classified into early-onset depression (< 50 years) and late-onset depression (≥ 50 years). HPA axis regulation was assessed by four morning saliva samples, two evening samples, and one awakening sample after .5 mg dexamethasone. Hippocampus and entorhinal cortex volume were manually outlined on three-dimensional T1-weighted magnetic resonance images. RESULTS: General linear models adjusted for demographics, vascular risk, antidepressant use, and white matter lesions showed that ever having had MDD was associated with smaller hippocampal volumes but not with entorhinal cortex volumes. Remitted MDD was related to smaller entorhinal cortex volumes (p < .05). Participants with early-onset depression had smaller hippocampal volumes than those who were never depressed (p < .05), whereas participants with late-onset depression had smaller entorhinal cortex volumes (p < .05). HPA axis activity did not explain these differences. CONCLUSIONS: We found differential associations of age of onset of depression on hippocampal and entorhinal cortex volumes, which could not be explained by alterations in HPA axis regulation.

Age-related changes in hypothalamic-pituitary-adrenal axis activity in patients with manifest arterial disease.

Reports on age-related changes of hypothalamic-pituitary-adrenal (HPA) axis activity are equivocal. In addition, subtle changes in HPA axis activity are associated with cardiovascular risk factors. This study evaluates the effect of age in a large sample of patients with arterial disease on several parts of the circadian rhythm of the HPA axis. Within the Second Manifestations of Arterial Disease-Magnetic Resonance (SMART-MR) study, a prospective cohort study among patients with manifest arterial disease, cross-sectional analyses were performed in 419 patients (age 63 ± 9 years). Circadian cortisol rhythm was assessed with six saliva samples, collected at awakening and 30, 45, and 60 min thereafter and at 10 and 11 pm. Furthermore, a low dose of dexamethasone (0.5 mg) was administered at 11 pm, and saliva was sampled the next morning to test the cortisol suppression. Linear regression analyses adjusted for sex, awakening time, workday, smoking, blood pressure, BMI, diabetes mellitus, and dyslipidemia showed that older age was associated with a blunted cortisol awakening response. Per year increase, the rise (ß = -0.15 nmol/l; 95%CI -0.25 to -0.05) and diurnal pattern (ß = -0.14 nmol/l; 95%CI -0.25 to -0.02) decreased. Furthermore, older age was associated with higher evening levels (ß log transformed = 0.01; 95%CI 0.01-0.02) and higher mean cortisol after dexamethasone (ß log transformed = 0.01; 95%CI 0.002-0.02). In patients with arterial disease, HPA axis activity showed reduced variability with older age, independent of cardiovascular risk factors.

Basal hypothalamic pituitary adrenal axis activity and hippocampal volumes: the SMART-Medea study.

BACKGROUND: It has frequently been hypothesized that high levels of glucocorticoids have deleterious effects on the hippocampus and increase risk for cognitive decline and dementia, but no large-scale studies in humans have examined the direct relation between hippocampal volumes and hypothalamic-pituitary-adrenal axis activity. METHODS: Cross-sectional analyses within the Second Manifestations of ARTerial disease-Magnetic Resonance (SMART)-Medea study, an ancillary study to the SMART-MR study on brain changes on magnetic resonance imaging (MRI) among patients with arterial disease. In 575 patients (mean age 62 +/- 9 years), diurnal cortisol rhythm was assessed with six saliva samples, collected at awakening; at 30, 45, and 60 min thereafter; and at 10 pm and 11 pm. A low dose of dexamethasone (.5 mg) was administered at 11 pm, and saliva was sampled the next morning at awakening. Volumetric measurements of the hippocampus were performed on a three-dimensional fast field echo T1-weighted scan with isotropic voxels. RESULTS: Mean total relative hippocampal volume was 6.0 +/- .7 mL. Linear regression analyses, adjusted for age, sex, vascular risk factors, and global brain atrophy showed that participants with higher evening levels and higher awakening levels after dexamethasone had smaller hippocampal volumes [B per SD (4.2) increase = -.09 mL; 95% confidence interval -.15 to -.03 mL and B per SD (2.5) increase = -.07 mL; 95% confidence interval -.13 to -.01 mL, respectively]. The awakening response was not significantly associated with hippocampal volumes. CONCLUSIONS: In this population, higher evening cortisol levels and reduced suppression after dexamethasone were associated with smaller hippocampal volumes, independent of total brain volume. The cortisol response after awakening was not associated with hippocampal volume.

Visual rating of the hippocampus in non-demented elders: Does it measure hippocampal atrophy or other indices of brain atrophy? The SMART-MR study.

Visual rating of hippocampal atrophy is often used to differentiate between normal aging and Alzheimer's disease. We investigated whether two visual rating scales of hippocampal atrophy were related to hippocampal volumes, and if visual rating was related to global, cortical and subcortical brain atrophy in persons without dementia. Within the SMART-MR study, a prospective cohort study among patients with manifest arterial disease, medial temporal lobe atrophy was qualitatively rated in 95 participants without dementia (mean age 62 +/- 10 years) using two visual rating scales: the medial temporal lobe (MTA) score was rated on coronal oriented images and the perihippocampal cerebrospinal fluid (HCSF) score was rated on axial oriented images. Hippocampal volume assessed by manual segmentation on a 3-dimensional FFE T1-weighted MR image. Automated segmentation was used to quantify volumes of brain tissue and cerebrospinal fluid. Total brain volume, gray matter volume, and ventricular volume were divided by intracranial volume to obtain brain parenchymal fraction (BPF), gray matter fraction (GMF) and ventricular fraction (VF). Using ANOVA, crude hippocampal volumes were smaller with increasing MTA and HSCF scores as were hippocampal volumes normalized for intracranial volume (P < 0.05). However, hippocampal volumes normalized for total brain size were not smaller with increasing MTA or HSCF scores (P = 0.33 and P = 0.49). Also, with increasing visual rating scores, BPF was smaller and VF was larger (P < 0.001), and the GMF decreased with increasing HCSF score (P = 0.008). In this nondemented population, visual rating of the medial temporal lobe reflects hippocampal atrophy as well as global and subcortical atrophy.