Purpose: This study was conducted to determine blood flow velocities and corresponding vessel diameters to characterize the response of the bulbar conjunctival microvasculature to contact lens wear.
Methods: A functional slit-lamp biomicroscope (FSLB), an adapted traditional slitlamp, was used to image the temporal bulbar conjunctiva of 22 healthy subjects before and after 6 hr of contact lens wear. All of the measurable venules on the conjunctiva were processed to yield vessel diameters and blood flow velocities.
Results: The average blood flow velocity increased from 0.51±0.20 to 0.65±0.22 mm/sec (P<0.001) after 6 hr of lens wear. The blood flow velocity distribution showed a velocity increase that correlated with the vessel diameter increase from the baseline (r=0.826, P<0.05). This pattern maintained a similar trend after 6 hr of lens wear (r=0.925, P<0.05), and increased velocities were found across all of the vessel diameter ranges (P<0.001).
Conclusions: Blood flow velocity increases across all of the vessel diameter ranges in response to contact lens wear. Functional slitlamp biomicroscope is capable of characterizing the bulbar microvascular response to contact lens wear.
Department of Ophthalmology (W.C.), Zhongshan Ophthalmic Centre, Sun Yat-sen University, Guangzhou, Guangdong, China; Department of Ophthalmology (W.C., Z.X., H.J., J.Z., J.W.), Bascom Palmer Eye Institute, University of Miami, Miami, FL; School of Ophthalmology and Optometry (Z.X.), Wenzhou Medical College, Wenzhou, Zhejiang, China; Department of Neurology (H.J.), University of Miami, Miami, FL; Department of Ophthalmology (J.Z.), Guangzhou Women and Children's Medical Center, Guangzhou, Guangdong, China; and Krieger School of Arts and Sciences (L.W.), Johns Hopkins University, Baltimore, MA.
Address correspondence to Jianhua Wang, M.D., Ph.D., Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, 1638 NW 10th Avenue, McKnight Building, Room 202A, Miami, FL 33136; e-mail: firstname.lastname@example.org
The authors have no conflicts of interest to disclose.
Supported in part by the research grants UM SAC (2015-27R1), NIH Center Grant P30 EY014801 and a grant from Research to Prevent Blindness (RPB).
Accepted November 23, 2015