BACKGROUND: Does the venous collapse phenomenon provide the possibility of venous dynamometry? METHOD: A technical model is presented which allows analysis of the conditions of the collapse of the central retinal vein in vitro. The conditions of the venous collapse were analysed with regard to intraocular pressure, intravasal pressure in the outflow of the central retinal vein and the overall perfusion. For clinical measurements dynamometry of the venous collapse is performed parallel to the experimental setting. RESULTS: The experiment reveals identical results for venous outflow pressure measured by venous dynamometry and by intravasal pressure detector. Venous dynamometry in vivo means that we use the onset of the venous collapse phenomenon to register the pressure in the central retinal vein at the point where it leaves the eye. Using this technique, retroocular obstruction of the venous outflow may be assessed. The venous outflow pressure itself depends on the venous flow resistance, intracranial pressure and arterial perfusion pressure. Any disorder of these three parameters may be assessed when the absolute venous outflow pressure is registered. CONCLUSION: The venous collapse phenomenon enables us to determine the venous outflow pressure. Clinical applications have proven promising.
BACKGROUND: Does the venous collapse phenomenon provide the possibility of venous dynamometry? METHOD: A technical model is presented which allows analysis of the conditions of the collapse of the central retinal vein in vitro. The conditions of the venous collapse were analysed with regard to intraocular pressure, intravasal pressure in the outflow of the central retinal vein and the overall perfusion. For clinical measurements dynamometry of the venous collapse is performed parallel to the experimental setting. RESULTS: The experiment reveals identical results for venous outflow pressure measured by venous dynamometry and by intravasal pressure detector. Venous dynamometry in vivo means that we use the onset of the venous collapse phenomenon to register the pressure in the central retinal vein at the point where it leaves the eye. Using this technique, retroocular obstruction of the venous outflow may be assessed. The venous outflow pressure itself depends on the venous flow resistance, intracranial pressure and arterial perfusion pressure. Any disorder of these three parameters may be assessed when the absolute venous outflow pressure is registered. CONCLUSION: The venous collapse phenomenon enables us to determine the venous outflow pressure. Clinical applications have proven promising.
Authors: Henry W Querfurth; Steven W Arms; Christoph M Lichy; William T Irwin; Thorsten Steiner Journal: Neurocrit Care Date: 2004 Impact factor: 3.210
Authors: Chandrakumar Balaratnasingam; William H Morgan; Martin L Hazelton; Phillip H House; Chris J Barry; Hsien Chan; Stephen J Cringle; Dao-Yi Yu Journal: Br J Ophthalmol Date: 2006-10-11 Impact factor: 4.638