The computerised tomography rating scale for schizophrenia (CTRSS): Validity and reliability

The elderly now constitute a very rapidly growing proportion of the population. It has been estimated that by the year 2020, more than 30% of the population in the United States will be more than 55 years of age.1 This demographic change necessitates imaging analysts to be aware of the imaging changes seen in normal aging of the brain. Meaningful interpretation of brain imaging studies necessitates understanding of the appearance of “normal” physiologic changes and the variety of neurodegenerative disorders that present in brain images of late middle-aged and elderly patients.Advances in brain imaging technology have resulted in a growing understanding of the imaging appearance of the aging process, although exact mechanisms are not well understood. In the brain, the normal aging process and some of the neurodegenerative disorders share the same imaging findings, although those associated with the neurodegenerative disorders occur more prematurely. Sulcal and ventricular enlargement seen on computed tomography (CT) or magnetic resonance (MR) images, periventricular and subcortical hyperintensities on MR images, and iron accumulation in certain areas of the brain are considered to represent neurodegenerative changes in neurologically intact elderly people. Significant gender differences exist in age-related brain degeneration.82