Date of Award

Summer 5-17-2019

Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Master of Science in Vision Science

Committee Chair

Amiee Ho

Second Advisor

James Kundart

Third Advisor

Ryan Bulson

Abstract

Abstract

Purpose: The purpose of this study is to look at the effect of dynamic and isometric exercise on systemic and ocular hemodynamics, such as heart rate, blood pressure, vessel density of radial papillary capillary (RPC), and how it relates to intraocular pressure (IOP) on healthy subjects.

Methods: In a prospective study design,participants performed two types of exercise: dynamic (aerobic cycling) vs isometric (strength training with resistance band). The subject’s IOP, heart rate, blood pressure, and retinal vessel density was measured pre- and post-exercise. The ocular perfusion pressure was calculated using the collected data.

Results:Forty participants (20 male, 20 female) between the ages of 18 and 30 years old (mean=24.3 years old, SD=3.4 years old) were enrolled. The effect of exercise type (dynamic vs. isometric) was significantly different forIOP (P =0.008), ocular perfusion pressure (OPP) (P <0.001), systolic blood pressure(SBP) (p <0.001), diastolic blood pressure(DBP) (P =0.02), heart rate(HR) (p <0.001), superior nasal (SN) (P =.019). Exercise had a significant effect on OPP (p <0.001), SBP (p <0.001), HR (p <0.001), RPC (p <0.001), SN (P =0.002), nasal superior (NS) (P =0.004), nasal inferior (NI) (p <0.001), inferior nasal (IN) (p <0.001), inferior temporal (IT) (p <0.001) in three different periods (baseline, treatment, and recovery). There was a moderately negative relationship between IOP and OPP (r (240) = -0.490, p <0.01). There was also a significant but weak relationship between IOP and measurements of DBP (r(240) = 0.134, P =0.038) and ST (r(221)= 0.192, P =0.004). A positive relationship was found between OPP with SBP (r (240) = 0.677, p <0.001) and OPP with DBP (r (240) = 0.660,p <0.001) largely because SBP and DBP are the variables used to calculate OPP.OPP was also positively correlated with HR (r(240) = 0.461, p <0.001and TS region (r(219) = 0.178,P =0.008) and negatively correlated to IN (r(222) = -0.148, P =0.028) and IT (r(222) = -0.159, P =0.017). Regression analysis showed vessel density of inferior/superior sectors were negatively related to OPP, the temporal sector was positively related to OPP, and the association between the nasal sector and OPP was not significant.

Conclusion: Dynamic exercise led to IOP decreas as OPP increased. After dynamic exercise, superior nasal vessel density % decreased more relative to isometric exercise from baseline. This decrease in retinal capillary engorgement in turn increases ocular perfusion pressure, which is preventative for glaucoma.

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