Histomorphometric Comparison of Diameter of Right and Left Vertebral Arteries

Introduction: It is evident that slight changes in the diameter of a vessel cause tremendous changes in its ability to conduct blood when the blood flow is streamline. The conduction of vessel increases in proportion to the diameter. Asymmetry of the vertebral arteries, with a larger left than right vessels has been described, but only few authors has recorded the dimensions. Aim: The present study was carried out to measure and compare Inner and Outer diameter of left and right vertebral artery. Material and Methods: 300 transverse annuli (sections) of vertebral artery were studied from 30 embalmed cadavers. Transverse annuli were processed and stained with Haematoxylin & Eosin. Stained slides were studied under the trinocular research microscope using 40x magnifications and the images obtained under microscope were transferred to computer and histological parameters were taken on computer images using Image-proplus software version 5.1. Inner and Outer diameter of transverse annuli were measured. Comparisons of left and right vertebral artery diameters were made using paired t test by SPSS version 15 software. Results: Inner diameter of left vertebral artery was 2.74 ± 0.46 mm and right vertebral artery was 2.64 ± 0.45 mm, the difference is statistically significant. Outer diameter of left vertebral artery was 3.16 ± 0.54 and right vertebral artery was 3.03 ± 0.51, hence the difference is statistically significant. Conclusion: The left sided vertebral artery was found to be dominant than the right side.