Morphometric analysis of the pituitary gland and sella turcica using computed tomography images in hamdani sheep

This study was conducted to obtain morphometric measurements of the pituitary gland and sella turcica in Hamdani sheep using computed tomography (CT) images, and to determine whether these measurements exhibit statistically significant differences in terms of sexual dimorphism. In this study, computed tomography (CT) images of the skulls from 16 adult and healthy Hamdani sheep (8 females and 8 males) were used. The measurements were taken from the images using the RadiAnt DICOM Viewer (64-bit) software. Morphometric measurements of the pituitary gland were obtained from transverse (length, height, width), dorsal (length, width), and sagittal (length, height) sections, and these values were used to calculate the volume of the gland. Additionally, using the pituitary gland measurements, the transverse index (TI), sagittal index (SI), and dorsal index (DI) were calculated. Furthermore, from the sagittal plane image of the sella turcica, nine osteometric parameters, including the surface area, were measured, and twelve ratio values were calculated based on length/height proportions. The collected data were then subjected to statistical analysis. In Hamdani sheep, it was observed that both the pituitary gland and sella turcica had larger linear measurements in males compared to females. The volume of the pituitary gland was found to be 1.211 ± 0.166 cm³ in female sheep and 1.911 ± 0.281 cm³ in male sheep. In both male and female sheep, all statistically significant correlations between age, body weight, and other measurements of the pituitary gland were found to be positive. However, in female Hamdani sheep, most of the correlations between linear measurements and index values were negative. Statistically significant osteometric measurements of the sella turcica in both male and female sheep also showed positive correlations. Conversely, the majority of the correlations between the height/width ratio of the sella turcica and both age and body weight were negative. When the measurement values were evaluated through ROC analysis, it was found that the transverse index (TI) and dorsal index (DI) of the pituitary gland, as well as the SMY/STU and SMY/CrCaU ratio values of the sella turcica, had statistically significant and high discriminatory power for sex differentiation based on the determined cut off values (p<0.05). In conclusion, morphometric differences in the pituitary gland and sella turcica between male and female Hamdani sheep were identified using computed tomography (CT) images, revealing clear evidence of sexual dimorphism. The findings of this study are expected to provide a scientific basis for future research in various fields such as the evaluation of potential pathological conditions of the pituitary gland and sella turcica in Hamdani sheep, taxonomic studies, sex determination, veterinary anatomy, surgery, clinical applications, and disciplines like zooarchaeology. Key words: Computed Tomography, Hamdani Sheep Morphometry, Pituitary Gland, Sella Turcica.