تفاوت جنسي در شاخص هاي آناتومي سطحي قشر جزيره در مغز افراد طبيعي يك مطالعه استريولوژيك و ماكروسكوپيك

Background: There are few and contradictory studies on sexual dimorphism in surface anatomical parameters in human brain (Cortical surface area and thickness). The objective of this study was to investigate the sex differences in surface anatomical parameters of the left insular cortex in healthy right-handed subjects. Materials and Methods: This cross- sectional descriptive study was performed on 72 human brains. The brains belonged to right - handed subjects who had died of non-neurologic causes. The brains were removed from the craniums no longer than 24 hours postmortem and were used for neuropathololgical studies. The area and thickness of the left insular cortex surface was estimated by using photographs of a series of 5mm coronal sections of left hemispheres with linear and point grids based on unbiased stereological method. The results were analysed by t-student test. Results: The brains of 38 men and 34 women were studied. The age range for men was 58-84 (69.3 ± 7.5) years and for women was 61-83 (67.2 ± 5.5) years. The mean value for outer surface area was 23.06 ± 4.65 cm^2 in men and 20.13 ± 3.65 cm^2 in women (P=0.007). The mean of inner surface area was 21.24 ± 5.56 cm^2 in men and 18.29 ± 3.24 cm^2 in women (p = 0.008). The mean surface area was 21.59 ± 5.50 cm2 in men and 19.30 ± 3.29 cm^2 in women (P=0.03). The mean of insular cortical thicknesses was 3.18 ± 0.8 mm in men and 3.04 ± 0.4 mm in women. Percentage of reduction in the outer and inner, areas as well as mean surface areas and the thicknesses of the insular cortex in women in relation to men were 11.9%, 13.9%, 10.6%, and 4.4%, respectively. Conclusion: Compared with women outer, inner and mean surface areas of left insular cortex in men were considerably larger; This study shows a significant larger (outer, inner, and mean) surface areas of the left insular cortex in men. However, the left insular cortical thicknesses were similar in both sexes. The functional significance of these differences and similarities is yet to be discovered.