Clinical applications and characteristics of apparent diffusion coefficient maps for the brain of two dogs

Diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) mapping are functional magnetic resonance imaging techniques for detecting water diffusion. DWI and the ADC map were performed for intracranial lesions in two dogs. In necrotizing leukoencephalitis, cavitated lesions contained a hypointense center with a hyperintense periphery on DWI, and hyperintense signals on the ADC maps. In metastatic sarcoma, masses including a necrotic region were hypointense with DWI, and hyperintense on the ADC map with hyperintense perilesional edema on DWI and ADC map. Since DWI and ADC data reflect the altered water diffusion, they can provide additional information at the molecular level.

Contrast-enhanced ultrasound analysis of renal perfusion in normal micropigs

Contrast-enhanced ultrasound is one of method for evaluating renal perfusion. The purpose of this project was to assess perfusion patterns and dynamics in normal micropig kidney using ultrasonographic contrast media. Eight young healthy micropigs were included in this study. Micropigs were anesthetized with propofol and received an intravenous bolus of microbubble contrast media through an ear vein. Time/mean pixel value (MPV) curves were generated for selected regions in the right renal cortex and medulla. The parenchyma was enhanced in two phases. The cortex was first enhanced followed by a more gradual enhancement of the medulla. A significant difference in perfusion was detected between the cortex and medulla. Following the bolus injection, the average upslope was 0.68 +/- 0.27 MPV/sec, downslope was -0.27 +/- 0.13 MPV/sec, baseline was 73.9 +/- 16.5 MPV, peak was 84.6 +/- 17.2 MPV, and time-to-peak (from injection) was 17.5 +/- 6.6 sec for the cortex. For the medulla, the average upslope was 0.50 +/- 0.24 MPV/sec, downslope was -0.12 +/- 0.06 MPV/sec, baseline was 52.7 +/- 7.0 MPV, peak was 65.2 +/- 9.3 MPV, and time-to-peak (from injection) was 27.5 +/- 5.0 sec. These data can be used as normal reference values for studying young micropigs.

Evaluation of the lateral ventricle using MRI in normal micropigs / 대한수의학회지

This study was undertaken to assess the lateral ventricle, which was some portion of brain and related to congenital anomalies, from 1, 2, 4, and 8 months of age in healthy micropigs. They were induced general anesthesia and performed magnetic resonance imaging (MRI) with a 0.3 Tesla magnet. Each age group was evaluated by three subjects such as lateral ventricular volume, ventricular volume ratio and asymmetry. T1 weighted transverse images were acquired for calculation of lateral ventricular and corresponding brain parenchyma areas. The ratio of bilateral ventricle areas used to analyze the asymmetry. The mean ventricular volumes of each month were 676.74 +/- 25.58 mm3 (1 month-old), 630.64 +/- 143.84 mm3 (2 month-old), 992.12 +/- 106.03 mm3 (4 month-old) and 1172.62 +/- 237.57 mm3 (8 month-old), respectively. The ventricular volume ratio was the smallest at 2 month-old and re-increased from that age. The ratio was significantly different between 2 month-old and other age groups (p < 0.05). The value of bilateral area ratio showed within 1.5 in all experimental animals. Consequently the lateral ventricle showed a positive correlation with aging and symmetric shapes in both sides. The developmental pattern of the lateral ventricle provides basic data in micropigs as an experimental animal model for physiological and neurosurgical approach.