Registration of Cadaver's Sectioned Images to Patient's Head MRIs / 대한의료정보학회지

OBJECTIVE: Cadaver's sectioned images with high resolution and real color could be used as the source of realistic three-dimensional images. If the sectioned images are registered to a patient's MRIs, three-dimensional images with high resolution and real color that fit the patient, can be produced; the three-dimensional images enable realistic virtual surgery for the patient. The objective of this study was to verify the registration of a cadaver's sectioned images to a patient's head MRIs. METHODS: The sectioned images of the heads of cadaver were associated with segmented images selected at 3 mm intervals. The patient had his head MR scanned at 3 mm intervals; the MRIs were segmented. Software to register the cadaver's sectioned images to the patient's MRIs was developed. On this software, the corresponding dots were identified on both the sectioned images and the MRIs either manually or automatically using segmented images. RESULTS: The registered sectioned images corresponded to the patient's MRIs. Both manual and automatic registrations were satisfied. CONCLUSION: Further study is needed for registering sectioned images to actual patients.

Three Dimensional MRI and Software for Studying Normal Anatomical Structures of an Entire Body

For identifying the pathological findings in magnetic resonance images (MRIs), normal anatomical structures in MRIs should be identified in advance. For studying the anatomical structures in MRIs, a learning tool that includes the followings is necessary. First, MRIs of the entire body; second, horizontal, coronal, and sagittal MRIs; third, segmented images corresponding to the MRIs; fourth, three dimensional (3D) images of the anatomical structures in the MRIs; fifth, software incorporating the MRIs, segmented images, and 3D images. Such a learning tool, however, is hard to obtain. Therefore, in this research, such a learning tool which helps medical students and doctors study the normal anatomical structures in MRIs was made as follows. A healthy young Korean male adult with standard body shape was selected. Six hundred thirteen MRIs of the entire body were scanned (slice thickness 3 mm, interslice gap 0 mm, field of view 480 mm x 480 mm, resolution 512 x 512, T1 weighted), and transferred to the personal computer. Sixty anatomical structures in the MRIs were segmented to make segmented images. Coronal, sagittal MRIs and coronal, sagittal segmented images were made. On the basis of the segmented images, forty-seven anatomical structures' 3D images were made by manual surface reconstruction method. Software incorporating the MRIs, segmented images, and 3D images was composed. This learning tool that includes horizontal, coronal, sagittal MRIs of the entire body, corresponding segmented images, 3D images of the anatomical structures in the MRIs, and software is expected to help medical students and doctors study the normal anatomical structures in MRIs. This learning tool will be presented worldwide through Internet or CD titles.

Manufacture of the Serially Sectioned Images of the Whole Body (Fourth Report: Methods for Selection and Treatment of the Cadaver and for Scanning of the MRIs and CTs) / 대한해부학회지

Visible Human Project dataset made in the United States has some problems which were caused by the cadaver selection, cadaver treatment, MRI (magnetic resonance image) scanning, and CT (computerized tomograph) scanning. Therefore, in this study, we intended to make better serially sectioned images, namely Visible Korean Human, which overcome the problems of Visible Human Project dataset. The better serially sectioned images will be the basis of better three dimensional images of the whole body, which are helpful in medical education An appropriate Korean male cadaver was selected for this study. Without injecting fixative, the cadaver's posture and direction were adjusted and fixed in an immobilizing box. Horizontal MRIs and CTs of the cadaver's whole body were scanned at 1 mm intervals. In addition, coronal and sagittal MRIs and CTs as well as movies of the MRIs and CTs were made. Age of the selected cadaver was young (32 years old), body size was Korean average (height 1,640 mm, weight 55 kg), and pathological findings were few. 1,718 couples of corresponding MRIs and CTs, in which anatomical structures appear clearly (pixel size 1 mm), were acquired. 276 couples of coronal MRIs and CTs as well as 505 couples of sagittal MRIs and CTs were acquired. Movies of all MRIs and CTs were acquired as well. The serially sectioned images acquired in this study will be helpful either in studying MRIs and CTs by referring to corresponding anatomical images or in studying anatomy and medicine by reconstructing MRIs, CTs, and anatomical images into three dimensional images.

Three-Dimensional Images and Software for Studying Anatomical Structures in MRIs / 체질인류학회지

Medical students and doctors should study the appearance of normal anatomical structures in the magnetic resonance images (MRIs). For this purpose, horizontal, coronal, sagittal MRIs of a healthy entire body and corresponding segmented images were prepared. However, it is inconvenient to select interesting MRIs and segmented images; and it is difficult to understand how stereoscopic anatomical structures appear in the MRIs. Therefore, in this research, a software, on which interesting MRIs can be conveniently displayed among the horizontal, coronal, sagittal MRIs and corresponding segmented images can be displayed together, was composed. And after stacking the segmented images, three-dimensional (3D) image of each anatomical structure was manually reconstructed by surface rendering. Then another software, on which interesting 3D images of anatomical structures can be displayed and rotated, was composed too. These softwares are expected to help medical students and doctors understand normal anatomical structures in the MRIs and read pathological findings in the MRIs of patients.

Comparison of White Matter Lesions on the Magnetic Resonance Imaging in Major Depression and Vascular Depression

OBJECTIVES: The aims of this study were to identify the frequency and severity of white matter lesions on MRIs of late-life depression and deppression due to cerebrovascular diseases (vascular depression), to evaluate the relation with cerebrovascular risk factors, and finally to understand an important cause of late-life depression. DESIGN: The frequency and severity of the periventricular hyperintensity and the deep white matter hyperintensity were measured on the brain MRIs in the patients with major depression, vascular depression and neurotic controls over 50 yrs of age. The association of the white matter lesions with cerebrovascular risk factors were evaluated. MATERIALS AND METHODS: The MRI films of 32 patients (15 males & 17 females) with major depression over 50 yrs of age, 25 patients (17 males & 8 females) with vascular depression, and 25 neurotic controls (6 males & 19 females) were analyzed for the white matter lesions according to the modified Fazekas criteria. The cerebrovascular risk factors including hypertension, arteriosclerosis, obesity, smoking, diabetes mellitus, thyroid function abnoramlities, EKG abnormality, stroke, etc were also assessed. RESULTS: 1) The frequency of periventricular lesions or deep white matter lesions were significantly higher in patients with vascular depression and major depression than in neurotic controls. 2) The intracerebral hyperintensities or classical infarctions were prevalent in frontal cortex (32.0%) and in basal ganglia (40.0%). 3) Among cerebrovascular risk factors, stroke (p<0.005), hypertension (p<0.025), EKG abnormality (p<0.005) and smoking (p<0.05) were significantly prevalent in the patients with vascular depression and major depression as compared with neurotic controls. 4) The severity of white matter lesions were significantly associated with the cerebrovascular risk factors (p<0.005) in patients with major depression over 50 yrs of age. CONCLUSIONS: The white matter hyperintensities on brain MRIs of patients with major depression over 50 yrs of age were significantly associated with cerebrovascular risk factors, which suggested a vascular origin of pathogenesis of late-life depression.