1.Fractal dimension, lacunarity, and cortical thickness in the mandible: Analyzing differences between healthy men and women with cone-beam computed tomography
Ingrid Garcia SANTOS ; Fernanda Ramos de FARIA ; Marcio José da Silva CAMPOS ; Beatriz Álvares Cabral de BARROS ; Gustavo Davi RABELO ; Karina Lopes DEVITO
Imaging Science in Dentistry 2023;53(2):153-159
Purpose:
The objective of this study was to assess the fractal dimension, lacunarity, trabecular microarchitecture parameters, and cortical linear measurements in the mandibles of male and female individuals to identify differences between them.
Materials and Methods:
In total, 116 cone-beam computed tomography scans of healthy individuals of different ages (57 men and 59 women, aged between 20 and 60 years) were selected. The following bone parameters were measured: 1) buccal, lingual, and basal cortical bone thickness in 5 standard parasagittal sections (the midline, the left and right sides of the lower lateral incisors, and the left and right sides of the lower canines); 2) the bone volume fraction of 10 sequential axial sections from each patient by creating a volume of interest in the area between the lower canines; and 3) fractal dimension and lacunarity using grayscale images of the same region of the volume ofinterest in the anterior mandible. Spearman correlation coefficients and the Mann-Whitney test were used.
Results:
A significant and positive correlation was found between age and cortical thickness, especially in the region of the central incisors. Significant differences between sexes in terms of fractal dimension, lacunarity, and bone volume were found. Women revealed lower fractal dimension values and higher lacunarity and bone volume ratiovalues than men.
Conclusion
Fractal dimension, lacunarity, trabecular bone volume, and cortical thickness were different between men and women of different ages. (Imaging Sci Dent 2023; 53: 153-9)
2.Ultrasound biomicroscopy for the assessment of early-stage nonalcoholic fatty liver disease induced in rats by a high-fat diet
Antonio Carlos Soares PANTALEÃO JR. ; Marcio Pinto DE CASTRO ; Krishynan Shanty Fernandes MEIRELLES ARAUJO ; Carlos Frederico Ferreira CAMPOS ; André Luiz Alves DA SILVA ; José Eduardo Ferreira MANSO ; João Carlos MACHADO
Ultrasonography 2022;41(4):750-760
Purpose:
The aim of this study was to assess the ability of ultrasound biomicroscopy (UBM) to diagnose the initial stages of nonalcoholic fatty liver disease (NAFLD) in a rat model.
Methods:
Eighteen male Wistar rats were allocated to control or experimental groups. A high-fat diet (HFD) with 20% fructose and 2% cholesterol, resembling a common Western diet, was fed to animals in the experimental groups for up to 16 weeks; those in the control group received a regular diet. A 21 MHz UBM system was used to acquire B-mode images at specific times: baseline (T0), 10 weeks (T10), and 16 weeks (T16). The sonographic hepatorenal index (SHRI), based on the average ultrasound image gray-level intensities from the liver parenchyma and right renal cortex, was determined at T0, T10, and T16. The liver specimen histology was classified using the modified Nonalcoholic Steatohepatitis Clinical Research Network NAFLD activity scoring system.
Results:
The livers in the animals in the experimental groups progressed from sinusoidal congestion and moderate macro- and micro-vesicular steatosis to moderate steatosis and frequent hepatocyte ballooning. The SHRI obtained in the experimental group animals at T10 and T16 was significantly different from the SHRI of pooled control group. No significant difference existed between the SHRI in animals receiving HFD between T10 and T16.
Conclusion
SHRI measurement using UBM may be a promising noninvasive tool to characterize early-stage NAFLD in rat models.