title: Correlation of Ocular Pulse Amplitude, Choroidal Thickness, and Internal Carotid Artery Doppler Ultrasound Findings in Normal Eyes.
abstract: BACKGROUND
  The choroid receives about 65-85% of ocular blood flow, which comes from the ophthalmic artery (OA), the first branch of the internal carotid artery (ICA). In the foveal avascular zone, there is no retinal vascular supply; therefore, choroidal blood supply plays a significant role in this subfoveal region. The ocular pulse amplitude (OPA) provides useful information about intraocular blood flow and is an indirect indicator of choroidal perfusion. In this study, we aimed to assess the correlation between the OPA, subfoveal choroidal thickness (CT), and ICA Doppler ultrasound findings in healthy eyes.
  
  
  METHODS
  In total, 48 eyes of 48 healthy volunteers were included in this study. All eyes underwent detailed ophthalmic evaluation, including slit-lamp biomicroscopy, fundus examination, axial length, OPA measurements, and optical coherence tomography (OCT) with enhanced depth imaging mode. Carotid Doppler ultrasound examination was performed by the radiologist. The correlation between the OPA, subfoveal CT, and ICA Doppler findings [peak systolic velocity (PSV) and end-diastolic velocity (EDV)] were evaluated, considering gender and age.
  
  
  RESULTS
  The mean OPA was 3.06 ± 1.34 mmHg. The mean subfoveal CT was 305.85 ± 33.98 µm. The mean PSV and EDV of ICA were 73.25 ± 23.63 cm/s and 26.93 ± 13.42 cm/s, respectively. A moderate positive correlation was found between OPA and subfoveal CT (p = 0.001; rho = 0.481). This relationship was present in both men and women. While a positive correlation was found between the OPA and subfoveal CT in subjects under the age of 50 years, there was no correlation in those over the age of 50 years.
  
  
  CONCLUSIONS
  A fair correlation was found between the OPA and subfoveal CT in healthy subjects under the age of 50.
authors.affiliation: a Ophthalmology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Gülizar
authors.initials: G
authors.lastname: Demirok
authors.affiliation: a Ophthalmology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Topalak
authors.affiliation: b Otorhinolaryngology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Mustafa M
authors.initials: MM
authors.lastname: Başaran
authors.affiliation: c Radiology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Gökçe K
authors.initials: GK
authors.lastname: Ataç
authors.affiliation: a Ophthalmology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Sertaç
authors.initials: S
authors.lastname: Öztürk
authors.affiliation: a Ophthalmology Department , Ufuk University Faculty of Medicine , Ankara , Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Sengün
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D001783:Blood Flow Velocity / Q000502:physiology*; D002343:Carotid Artery, Internal / Q000502:physiology*; D002829:Choroid / Q000033:anatomy & histology / Q000098:blood supply; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011673:Pulsatile Flow / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology*; D041623:Tomography, Optical Coherence; D018608:Ultrasonography, Doppler
keywords: Choroidal blood flow; Doppler ultrasound of ICA; EDI mode OCT; choroidal thickness; ocular pulse amplitude