Related Experiment Video
Updated: Jun 12, 2025

Doppler Optical Coherence Tomography of Retinal Circulation
Published on: September 18, 2012
Characterization of Vortex Vein Drainage System in Healthy Individuals Imaged by Ultra-Widefield Optical Coherence
Zhonghua Luo1, Yue Xu1, Xiaomei Xiong1
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China.
Purpose:
The purpose of this study was to investigate the choroidal characteristics of vortex vein (VV) drainage systems in healthy individuals using ultra-widefield optical coherence tomography angiography.
Methods:
The mean choroidal thickness (ChT) and choroidal vascularity index (CVI) of each VV quadrant (24 × 20 mm2 scan mode; superotemporal [ST], superonasal [SN], inferonasal [IN], and inferotemporal [IT] quadrants) were calculated. Furthermore, intervortex venous anastomosis (IVA) was classified into temporal, superior, inferior, and nasal types.
Results:
A total of 207 healthy eyes were analyzed to find that the ST quadrant had the thickest choroidal layer and highest CVI (all P < 0.05). Among the four VV drainage quadrants, the mean ChT and CVI decreased in the sequence of ST, SN, IT, and IN (all P < 0.05). Moreover, men had a higher CVI than women in all VV quadrants (all P < 0.05). IVA was observed in all VV quadrants of 91 eyes (43.96%), and in the macular region of 33 eyes (15.94%).
Conclusions:
The ST drainage system was identified as the preferred VV drainage route in healthy eyes. Among the four VV drainage quadrants, the drainage system adhered to the ST-SN-IT-IN order of descending perfusion. Furthermore, age- and sex-related differences were noted in the choroidal VV drainage systems of healthy eyes. Additionally, almost half of the healthy eyes had IVA in their choroidal vessel networks.
Translational Relevance:
The VV drainage system may be considered a novel imaging biomarker for ocular diseases.
Related Concept Videos
Overview of Systemic Veins
The coronary sinus, the heart's principal vein, resides in the coronary sulcus on the heart's posterior aspect. This broad venous channel receives nearly all venous blood from the myocardium, the heart muscle. It is fed by three primary veins: the great cardiac vein, the...
Anatomy of Blood Vessels
Arteries
Arteries circulate oxygenated blood from the heart, except the pulmonary artery, which transports deoxygenated blood to the lungs. Large arteries, such as the aorta,...
Venous Return
What is Venous Return?
Venous return refers to the rate at which blood flows back to the heart from the body's peripheral veins. It's an integral part of the circulatory system...
Veins as Blood Reservoirs
Veins of the Abdomen and Pelvis
The inferior vena cava is fed by numerous smaller veins. The lumbar veins, for instance, drain the posterior abdominal wall, emptying both directly into the inferior vena cava and into the...
Veins of Head and Neck
On the other hand, the vertebral veins, unlike their arterial counterparts, are not primarily responsible for brain drainage. Instead, they drain the cervical vertebrae, spinal cord, and some small...

