Does the Bursa Pre-Macularis protect the fovea from shear stress? A possible mechanical role.
Exp Eye Res
; 175: 159-165, 2018 10.
Article
em En
| MEDLINE
| ID: mdl-29935948
ABSTRACT
Purpose of present study is to evaluate whether the Pre-Macular Bursa (PMB) modifies Wall Shear Stress (WSS) at the retinal surface during saccadic movements. We created a mathematical model consisting of 25,000 grid cells and simulated a horizontal saccade spanning 50° in 0.17s, both in absence and in presence of the PMB. Wall Shear Stress SS was computed throughout the retinal surface and the posterior pole was divided into 3 Zones comprising 400 nodes each Zone 1 (radius 3.5â¯mm; 0°-17°) corresponding to the PMB area; Zone 2 (concentric annular area 5â¯mm in radius; 22°) and Zone 3 (concentric annular area 5.5â¯mm; 28°). The PMB reduced WSS significantly at the macula and increased it in the immediate surroundings. Average WSS in Zone 1 was 1.53⯱â¯1.01 (max 4.23â¯Pa) with PMB Vs 6.94⯱â¯9.23 (max 35.83â¯Pa) without. Zone 2 WSS was 9.39⯱â¯10.33 (max 48.36â¯Pa) with PMB Vs 6.95⯱â¯9.40 (max 38.60â¯Pa) without Zone 3 WSS was 8.41⯱â¯10.03 (max 43.16â¯Pa) with PMB Vs 6.88⯱â¯9.42 (max 39.43â¯Pa) without (pâ¯<â¯0.001 in all cases). The PMB significantly reduces WSS over the retinal surface underlying the bursa region; conversely, WSS slightly increases it in the immediate neighboring areas.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Estresse Mecânico
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Corpo Vítreo
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Hidrodinâmica
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Fóvea Central
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Modelos Teóricos
Limite:
Humans
Idioma:
En
Revista:
Exp Eye Res
Ano de publicação:
2018
Tipo de documento:
Article