Relationship of spontaneous retinal vein pulsation with ocular circulatory cycle.
OBJECTIVE
To determine the timing of spontaneous venous pulsation (SVP) relative to the ocular circulatory cycle by using the movie tool of confocal scanning laser ophthalmoloscope.


METHODS
A video recording of the fundus was obtained using a confocal scanning laser ophthalmoscope (Spectralis HRA, Heidelberg Engineering, Heidelberg, Germany) at 8 frames/s in 47 eyes (15 glaucoma patients and 32 glaucoma suspects) with visible pulsation of both the central retinal artery (CRA) and vein (CRV). The timing of the maximum and minimum diameters of the CRA (CRA(max) and CRAmin, respectively) and CRV (CRV(max) and CRV(min), respectively) was identified during four pulse cycles. The interval between CRV(min) and CRA(min), and between CRV(max) and CRA(max) was expressed as the number of frames and as a percentage of the ocular circulatory cycle.


RESULTS
The ocular circulatory cycle (from one CRA(max) to the next) lasted 7.7 ± 1.0 frames (958.8 ± 127.2 ms, mean ± SD), with a mean pulse rate of 62.6 beats/min. The diameter of the CRA was increased for 2.4 ± 0.5 frames (301.9 ± 58.8 ms) and decreased for 5.3 ± 0.9 frames (656.9 ± 113.5 ms). CRV(max) occurred 1.0 ± 0.2 frames after CRA(max) (equivalent to 13.0% of the ocular circulatory cycle), while CRV(min) occurred 1.1 ± 0.4 frames after CRA(min) (equivalent to 14.6% of the ocular circulatory cycle).


CONCLUSIONS
During SVP, the diameter of the CRV began to decrease at early diastole, and the reduction persisted until early systole. This finding supports that CRV collapse occurs during ocular diastole.
Department of Ophthalmology, Konyang University, Kim's Eye Hospital, Myung-Gok Eye Research Institute, Seoul, Korea; Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Mijin
M
Kim
Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Eun Ji
EJ
Lee
Department of Ophthalmology, Pusan National University Yangsan Hospital, Pusan, Korea.
Je Hyun
JH
Seo
Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Tae-Woo
TW
Kim
D000368:Aged; D005123:Eye / Q000098:blood supply*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D019721:Ophthalmoscopes; D011674:Pulse; D012039:Regional Blood Flow / Q000502:physiology*; D012079:Renal Circulation; D012161:Retinal Artery; D012169:Retinal Vein; D012189:Retrospective Studies