title: Spectral-domain optical coherence tomography of the choroid during valsalva maneuver.
abstract: OBJECTIVE
  To evaluate the influence of Valsalva maneuver on the morphology and thickness of the choroid at the macular area.
  
  
  METHODS
  Prospective interventional case series.
  
  
  METHODS
  Institutional setting. Nine healthy volunteers performed macular spectral-domain optical coherence tomography using enhanced-depth imaging at rest and during a Valsalva maneuver. Horizontal and vertical B-scans centered on the fovea were acquired. Subfoveal and average choroidal thickness in the central 3 mm were compared in the resting position and during the Valsalva maneuver using manual and semiautomatic measuring tools. Changes in choroidal thickness were evaluated.
  
  
  RESULTS
  There was no statistically significant difference in choroidal thickness at rest or during Valsalva maneuver in any of the compared groups. The subfoveal thickness difference was -4.1 μm on horizontal scans (P = .28) and 1.4 μm on vertical scans (P = .75). The mean choroidal thickness difference in the central 3000 μm was 8.5 μm on horizontal scans (P = .73) and -5.3 μm on vertical scans (P = .41).
  
  
  CONCLUSIONS
  Valsalva maneuver does not change choroidal thickness at the posterior pole. The increase in ocular pressure caused by this maneuver cannot be explained by an increase in choroidal thickness in this portion of the uveal tract.
authors: Department of Ophthalmology of Hospital de São João, Porto, Portugal. falcao@med.up.pt
authors: Manuel
authors: M
authors: Falcão
authors: Marco
authors: M
authors: Vieira
authors: Pedro
authors: P
authors: Brito
authors: Amândio
authors: A
authors: Rocha-Sousa
authors: Elisete M
authors: EM
authors: Brandão
authors: Fernando M
authors: FM
authors: Falcão-Reis
mesh_terms: D000328:Adult; D002829:Choroid / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D014636:Valsalva Maneuver / Q000502:physiology*; D014690:Venous Pressure / Q000502:physiology