Computed tomography in small animals – Basic principles and state of the art applications

Quantitative computed tomography of the liver in dogs submitted to prednisone therapy

“…CT in animals, as well as verified in humans, allows for the diagnosis of hepatic steatosis in a less invasive manner when compared with biopsy, laparotomy and laparoscopy techniques. Some authors (Ohlerth and Sharf, 2007) verified a significant reduction of hepatic radiodensity in cats with lipidosis when compared with the control group. According to reports, there is a decrease in hepatic radiodensity of approximately 1.0 to 1.5 HU for each 1% increase in the concentration of lipids in the organ (Leander et al, 2000;Kodama et al, 2007).…”

“…Computed tomography (CT) exams present a broad variety of indications for dogs and cats, becoming an important tool for the establishment of several diagnoses (Smallwood and George, 1993;Rockall et al, 2003;Nakamura et al, 2005;Ohlerth and Sharf, 2007;. The evaluation of abdominal organs' radiodensity is widely performed in human patients (Leander et al, 2000;Tsujimoto et al, 2006, Kodama et al, 2007 and can be employed with high precision and reproducibility in animals, helping in the diagnosis of alterations in several organs (Ohlerth andSharf, 2007, Teixeira et al, 2007;Costa et al, 2010).…”

“…The evaluation of abdominal organs' radiodensity is widely performed in human patients (Leander et al, 2000;Tsujimoto et al, 2006, Kodama et al, 2007 and can be employed with high precision and reproducibility in animals, helping in the diagnosis of alterations in several organs (Ohlerth andSharf, 2007, Teixeira et al, 2007;Costa et al, 2010). A recent study demonstrated the occurrence of steroid hepatopathy in a dog subjected to prolonged corticosteroid therapy, with an increase of the parenchymal liver radiodensity (Costa et al, 2011).…”

3D Modeling of Abdominal Surface Area in Cats

“…Nevertheless, these techniques allow a great step forward since it is very difficult to measure internal cavities with exact methods [4,[17][18][19]. The described technique of 3D modelling of anatomical structures are associated with some error, when compared with the actual structures; the literature describes errors between 2.9 % and 4.95 %, an error considered quite low [23,24,27]. The 3D anatomical model of the abdominal cavity of cats is in accordance with what is described in the anatomic literature: a structure without major changes in terms of shape between individuals, and without major changes in terms of volume and area [1,2].…”

“…Since 1970, the computed axial tomography (CT) has revolutionized the radiological diagnosis; it was also the first tomographic technique to be combined with computational calculation [24]. Since then, there has been great technological development, allowing the use of these techniques to determine and calculate anatomical parameters of various organs with precision, when compared with real models [23,[25][26][27][28].…”