PT  - JOURNAL ARTICLE
AU  - Fei Li
AU  - Kai Gao
AU  - Xingyi Li
AU  - Shida Chen
AU  - Wenbin Huang
AU  - Xiulan Zhang
TI  - Anterior but not posterior choroid changed before and during Valsalva manoeuvre in healthy Chinese: a UBM and SS-OCT study
AID  - 10.1136/bjophthalmol-2016-309881
DP  - 2017 Dec 01
TA  - British Journal of Ophthalmology
PG  - 1714--1719
VI  - 101
IP  - 12
4099  - http://bjo.bmj.com/content/101/12/1714.short
4100  - http://bjo.bmj.com/content/101/12/1714.full
SO  - Br J Ophthalmol2017 Dec 01; 101
AB  - Purpose To determine if the anterior choroid is involved in ocular change during the Valsalva manoeuvre (VM).Materials and methods Fifty-three healthy volunteers aged 18–65 years with normal visual field test results and no history of intraocular pressure (IOP) exceeding 21 mm Hg were recruited. Anterior and posterior choroidal changes before and during VM were recorded by ultrasound microscope and swept-source optical coherence tomography, respectively. Parameters of the anterior segment included ciliary body thickness (CBT0), thickness of the choroid at a distance of 4 mm from the root of the iris (CT4), anterior placement of the ciliary body (APCB) and trabecular–ciliary angle (TCA). Thickness of different layers of retina and posterior choroid were also measured and compared before and during VM. IOP, blood pressure (BP), heart rate (HR), axial length, spherical equivalent refractive error and pupil diameter (PD) were also recorded and analysed.Results VM caused elevated IOP, systolic BP, diastolic BP and increased HR. There was a significant increase in anterior parameters including CBT0, CT4 and APCB (p<0.001), but not in TCA or PD (p>0.05). The mean change of CBT0, CT4 and APCB were: from 1.00±0.09 mm to 1.11±0.10 mm (p<0.001), from 0.29±0.04 mm to 0.36±0.05 mm (p<0.001), from 0.76±0.11 mm to 0.88±0.13 mm (p<0.001), respectively. However, there is no significant change in posterior choroid (from 215.74±60.23 µm to 214.82±61.32 µm, p=0.17).Conclusion We found that VM did not affect the posterior choroid, but it did cause thickening of the anterior choroid and the ciliary body, both of which led to a larger anterior placement of the ciliary body and a narrowed anterior chamber. The anterior (but not the posterior) choroid could be related to IOP elevation and a narrowed anterior chamber in primary angle closure diseases.