Relationship between plasma levels of vasoactive mediators and optic nerve head circulation shown by laser speckle flowgraphy.
METHODS
To evaluate relationships between optic nerve head (ONH) circulation by laser speckle flowgraphy (LSFG), and secretion levels of plasma norepinephrine (NE), plasma renin activity (PRA), plasma aldosterone concentration (PAC), and plasma cortisol.


METHODS
Forty subjects were included in the study. The mean blur rates (MBR) throughout the ONH (MBR-all), in the tissue (MBR-tissue), and in vessels (MBR-vessel) were analyzed. In 29 subjects the following parameters were evaluated: plasma NE and ONH circulation in the evening and morning (Δ plasma NE, Δ MBR-all, -tissue, -vessel, and Δ area ratio of blood stream).


RESULTS
Plasma NE was significantly correlated with MBR-all (r = 0.39, P = 0.01) and MBR-vessel (r = 0.51, P = 0.0008). Plasma cortisol was significantly correlated with MBR-vessel (r =0.35, P = 0.03). The PRA (r = 0.31, P = 0.05) and PAC (r = 0.31, P = 0.05) tended to correlate with MBR-vessel. The multiple regression analysis revealed that plasma NE, PAC, and ocular perfusion pressure (OPP) were identified as factors contributing independently to the MBR-vessel (plasma NE: standard regression = 0.48, t-value = 3.12, P = 0.004; PAC: 0.43, 3.10, 0.04; OPP: 0.58, 2.34, 0.03, r = 0.71). Positive correlations between Δ plasma NE and Δ MBR-all (r = 0.46, P = 0.01), Δ MBR-tissue (0.38, 0.04), Δ MBR-vessel (0.41, 0.03), and Δ area ratio of blood stream (0.38, 0.04) were observed.


CONCLUSIONS
Our results clarified that the measurements of ONH circulation by LSFG is reflecting the plasma secretion levels of vasoactive mediators.
Department of Ophthalmology, School of Medicine, Toho University, 6-11-1, Omori-Nishi, Ota-ku, Tokyo, 143-8541, Japan. tomoaki-s@med.toho-u.ac.jp.
Tomoaki
T
Shiba
Nakano Eye Clinic of Kyoto Medical Co-operative, 2, Kyoto, Japan.
Tetsuya
T
Sugiyama
Department of Ophthalmology, School of Medicine, Toho University, 6-11-1, Omori-Nishi, Ota-ku, Tokyo, 143-8541, Japan.
Yuichi
Y
Hori
Department of Ophthalmology, School of Medicine, Toho University, 6-11-1, Omori-Nishi, Ota-ku, Tokyo, 143-8541, Japan.
Tadashi
T
Matsumoto
Department of Ophthalmology, Toho University Sakura Medical Center, Chiba, Japan.
Takatoshi
T
Maeno
Cardiovascular Center, Toho University Sakura Medical Center, Chiba, Japan.
Mao
M
Takahashi
D000450:Aldosterone / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007429:Intraocular Pressure / Q000502:physiology; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood*; D009898:Optic Disk / Q000098:blood supply*; D012039:Regional Blood Flow; D012083:Renin / Q000097:blood*; D012171:Retinal Vessels / Q000502:physiology*
D000450:Aldosterone; D012083:Renin; D006854:Hydrocortisone; D009638:Norepinephrine
Laser speckle flowgraphy; Optic nerve head; Plasma aldosterone concentration; Plasma cortisol; Plasma norepinephrine; Plasma renin activity