Cerebral white matter changes (WMCs) and silent brain infarcts (SBIs) are common radiologic findings in neurologically asymptomatic elderly people, but are associated with an increased risk of subsequent stroke. We investigated the prevalence and risk factors for these cerebral changes on brain computed tomography (CT) in 480 community-dwelling healthy Korean adults without stroke or dementia, who were recruited for an early health program. Cerebral WMCs were defined as the presence of approximately 5 mm wide ill-defined and moderately hypodense lesions, and SBIs were defined as the presence of >2 mm wide well-defined hypodense lesions. Of the 480 patients, 49 (10.2%) had cerebral WMCs and SBIs findings on brain CT. The prevalence of WMCs and SBIs increased with age: the prevalence was 2.4%, 9%, and 32% for subjects in their 50, 60s, and 70s, respectively. In addition, hypertension, abdominal obesity, increased levels of homocysteine and high sensitivity C-reactive protein were significantly associated with cerebral WMCs and SBIs. Our study suggests that regular monitoring of risk factors is required to prevent cerebral WMCs and SBIs and decrease the incidence of stroke and dementia in healthy individuals.

No abstract available.
Carotid Arteries*

Depth of prostate volume from the skin can vary due to intra-fractional and inter-fractional movements, which may result in dose reduction to the target volume. Therefore we evaluated the feasibility of automated depth determination-based adaptive proton therapy to minimize the effect of inter-fractional movements of the prostate. Based on the center of mass method, using three fiducial gold markers in the prostate target volume, we determined the differences between the planning and treatment stages in prostate target location. Thirty-eight images from 10 patients were used to assess the automated depth determination method, which was also compared with manually determined depth values. The mean differences in prostate target location for the left to right (LR) and superior to inferior (SI) directions were 0.9 mm and 2.3 mm, respectively, while the maximum discrepancies in location in individual patients were 3.3 mm and 7.2 mm, respectively. In the bilateral beam configuration, the difference in the LR direction represents the target depth changes from 0.7 mm to 3.3 mm in this study. We found that 42.1%, 26.3% and 2.6% of thirty-eight inspections showed greater than 1 mm, 2 mm and 3 mm depth differences, respectively, between the planning and treatment stages. Adaptive planning based on automated depth determination may be a solution for inter-fractional movements of the prostate in proton therapy since small depth changes of the target can significantly reduce target dose during proton treatment of prostate cancer patients.
Humans ; Prostate ; Prostatic Neoplasms ; Proton Therapy ; Protons ; Skin

Depth of prostate volume from the skin can vary due to intra-fractional and inter-fractional movements, which may result in dose reduction to the target volume. Therefore we evaluated the feasibility of automated depth determination-based adaptive proton therapy to minimize the effect of inter-fractional movements of the prostate. Based on the center of mass method, using three fiducial gold markers in the prostate target volume, we determined the differences between the planning and treatment stages in prostate target location. Thirty-eight images from 10 patients were used to assess the automated depth determination method, which was also compared with manually determined depth values. The mean differences in prostate target location for the left to right (LR) and superior to inferior (SI) directions were 0.9 mm and 2.3 mm, respectively, while the maximum discrepancies in location in individual patients were 3.3 mm and 7.2 mm, respectively. In the bilateral beam configuration, the difference in the LR direction represents the target depth changes from 0.7 mm to 3.3 mm in this study. We found that 42.1%, 26.3% and 2.6% of thirty-eight inspections showed greater than 1 mm, 2 mm and 3 mm depth differences, respectively, between the planning and treatment stages. Adaptive planning based on automated depth determination may be a solution for inter-fractional movements of the prostate in proton therapy since small depth changes of the target can significantly reduce target dose during proton treatment of prostate cancer patients.
Humans ; Prostate ; Prostatic Neoplasms ; Proton Therapy ; Protons ; Skin