Vortex vein exit sites. Scleral coordinates

Abstract

Purpose: The authors determined the frequency and scleral coordinates of vortex vein exit sites in 46 autopsy eyes to provide topographic data that will enable surgeons to locate these vessels more precisely.

Methods: Forty-six autopsy eyes were examined under a dissecting microscope to measure the frequency of vortex veins and the cord lengths between the vortex vein scleral exit sites and the limbus, rectus muscle insertions, and oblique muscle insertions.

Results: Data from this study showed that 32 (70%) of the 46 individual eyes studied had more than four vortex veins. The number of second or third vortex veins found in the nasal quadrants was significantly higher than the number found in the temporal quadrants (P < 0.01). Statistical analyses of the measurements provided mean values for distances between vortex vein scleral exit sites and the three nearest extraocular muscle insertions; these positions among eyes were found to be relatively uniform (standard deviation, 0.7-2.5 mm).

Conclusion: The authors suggest that the majority of adult eyes encountered by a surgeon will have more than four vortex vein exit sites and that more vortex veins may be expected in the nasal quadrants than in the temporal quadrants. This study delineates the locations of vortex vein exit sites so that surgeons can reliably predict their surface positions to avoid vessel laceration and its ensuing complications.