Computer aided diagnosis of acute intracranial hemorrhage on brain CT

Acute intracranial hemorrhage (AIH) is a major cause of neurological disturbance or complication of head injury. Its presence dictates different management strategy. In modern medicine, detection of AIH relies on the use of brain computed tomography (CT). But diagnosis of AIH can become difficult when the lesion is inconspicuous or the reader is inexperienced.;The objective of the current project is to develop a computer aided diagnosis (CAD) system that improves the diagnostic performance of AIH on CT by clinicians.;A total of 186 cases, including all 62 continuous cases that showed AIH not more than 1 cm in size obtained during a 6 month period, and 124 randomly selected controls that were obtained during the same period, were retrospectively collected from the CT archive of Princess Margaret Hospital. The imaging diagnoses were established by consensus of two experienced radiologists.;A CAD was designed and implemented. It reads and processes standard DICOM image files. Intracranial contents are segmented from the CT images, which are then subjected to denoising and adjustment for CT cupping artifacts. AIH candidates are extracted from the intracranial contents based on top-hat transformation and subtraction between two sides of the image about the mid-sagittal plane. AIH candidates are registered against a normalized coordinate system such that the candidates are rendered anatomical information. True AIH is differentiated from mimicking normal variants or artifacts by a knowledge based classification system incorporating rules that make use of quantified imaging features and anatomical information.