Purchase this article with an account.
Meghal Gagrani, Shan Fan, Vikas Gulati, Sachin Kedar, David Reed, Carol B Toris, Arthur J Sit, Sayoko E Moroi, Deepta Abhay Ghate; The epidemiology of episcleral venous pressure (EVP). Invest. Ophthalmol. Vis. Sci. 2021;62(8):474.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
EVP is a significant determinant of intraocular pressure (IOP) in the Goldmann equation and is a potential rapid and non-invasive biomarker for intracranial pressure (ICP).The variability of EVP with demographic variables, systemic and ocular characteristics is yet to be elucidated. This study aims to evaluate the epidemiology of EVP.
A post hoc analysis was conducted of collated data from aqueous humor dynamics studies of healthy adults at UNMC (Nebraska), Mayo Clinic (Minnesota) and U Michigan (Michigan). Systemic parameters measured were weight, height, BMI, neck circumference (NC), pulse rate, systolic (SBP) and diastolic blood pressures (DBP). Mean arterial pressure (MAP) was calculated. Seated IOP was measured using a pneumatonometer (Reichert, USA). Seated EVP was measured using a slit lamp mounted venomanometer (Eyetech USA). Two sites subjectively chose endpoints and the third site added video capture of endpoints. Two to three readings were collected and averaged. Central corneal thickness (CCT), anterior chamber depth (ACD) and axial length (AL) were collected with ultrasound instruments. Biweight midcorrelations were used to study the effect of different variables on EVP. Right eye (OD) and left eye (OS) of each subject were independently correlated with each variable.
Data from 201 subjects (n = 201 eyes) (mean age of 46 ± 16 years and range of 15 to 81 years) were analyzed. 76% were females (Table 1) and 85% were White. All variables were normally distributed except age, which was bimodally distributed. Data is presented as mean ± SD unless stated otherwise. Mean values were weight 78 ± 18 kg, height 166 ± 9 cm, BMI 28 ± 5 and NC 37 ± 4 cm. Pulse rate was 72 ± 13 beats per minute and SBP, DBP, and MAP were 123 ± 15, 77 ± 10, and 92 ± 12 mmHg, respectively. All ocular measurements were correlated between OD and OS. Ocular parameters were EVP 7.9 ± 1.6 mmHg (range 3 to 14 mmHg), IOP 15.7 ± 2.7 mmHg (range 7 to 22 mmHg), CCT 557 ± 40 mm, ACD 3.4 ± 0.3 mm and AL 24 ± 1 mm. None of the systemic or ocular measurements had any significant correlation with EVP or IOP (Figure 1). All variables showed similar relationships for OD and OS eyes and in males and females.
EVP was not found to be correlated with any systemic or ocular parameters. A small range of distribution and the ability to measure EVP non-invasively would make it an excellent biomarker for raised ICP.
This is a 2021 ARVO Annual Meeting abstract.
This PDF is available to Subscribers Only