Abstract
Retinal artery occlusion (RAO) is a common ocular vascular occlusive disorder that may lead to partial or complete retinal ischemia with sudden visual deterio ration and visual field defects. Although RAO has been investigated since 1859, the main mechanism is still not fully understood. While hypoperfusion of the ophthalmic artery (OA) due to severe stenosis of the internal carotid artery might lead to RAO, emboli are assumed to be the main reason. Intra-arterial thrombolysis is not a sufficient treatment for RAO, and current research is mainly focused on risk factors. In this study, a computational fluid dynamic model is presented to analyse flow conditions and clot behaviour at the junction of the internal carotid artery and OA based on a realistic geometry from a RAO patient. Clot diameters varied between 5 and 200 μm, and the probability of clots reaching the OA or being washed into the brain was analysed. Results show sufficient blood flow and perfusion pressure at the end of OA. The probability that clots from the main blood flow will to be washed into the brain is 7.32±1.08%. A wall shear stress hotspot is observed at the curvature proximal to the internal carotid artery/OA junction. Clots released from this hotspot have a higher probability of causing RAO. The occurrence of such patient-specific pathophysiologies will have to be considered in the future.
References
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©2014 by De Gruyter
Articles in the same Issue
- Frontmatter
- Research articles
- Analysis of emboli and blood flow in the ophthalmic artery to understand retinal artery occlusion
- Material properties in unconfined compression of gelatin hydrogel for skin tissue engineering applications
- Red light as a 12-oxo-leukotriene B4 antagonist: an explanation for the efficacy of intensive red light in the therapy of peripheral inflammatory diseases
- Tightening of healing abutments: influence of torque on bacterial proliferation risk, an in vitro investigation
- Influence of superstructure geometry on the mechanical behavior of zirconia implant abutments: a finite element analysis
- Biomechanical investigations of the secondary stability of commercial short dental implants in porcine ribs
- Automatic camera-based identification and 3-D reconstruction of electrode positions in electrocardiographic imaging
- An automatic saccadic eye movement detection in an optokinetic nystagmus signal
- Case Report
- Monitoring of lobectomy in cystic fibrosis with electrical impedance tomography – a new diagnostic tool
- Letters to the Editor
- Accelerometer-based goniometer for smartphone and manual measurement on photographs: do they agree?
- Reply to: Accelerometer-based goniometer for smartphone and manual measurement on photographs: do they agree?
Articles in the same Issue
- Frontmatter
- Research articles
- Analysis of emboli and blood flow in the ophthalmic artery to understand retinal artery occlusion
- Material properties in unconfined compression of gelatin hydrogel for skin tissue engineering applications
- Red light as a 12-oxo-leukotriene B4 antagonist: an explanation for the efficacy of intensive red light in the therapy of peripheral inflammatory diseases
- Tightening of healing abutments: influence of torque on bacterial proliferation risk, an in vitro investigation
- Influence of superstructure geometry on the mechanical behavior of zirconia implant abutments: a finite element analysis
- Biomechanical investigations of the secondary stability of commercial short dental implants in porcine ribs
- Automatic camera-based identification and 3-D reconstruction of electrode positions in electrocardiographic imaging
- An automatic saccadic eye movement detection in an optokinetic nystagmus signal
- Case Report
- Monitoring of lobectomy in cystic fibrosis with electrical impedance tomography – a new diagnostic tool
- Letters to the Editor
- Accelerometer-based goniometer for smartphone and manual measurement on photographs: do they agree?
- Reply to: Accelerometer-based goniometer for smartphone and manual measurement on photographs: do they agree?