Intracranial Pressure and Ocular Hemodynamics

A machine learning approach in the non-invasive prediction of intracranial pressure using Modified Photoplethysmography

“…This indicates that ophthalmodynamometry is an important component of our image acquisition methodology. Moreover, the findings are consistent with the high correlation between retinal venous opening pressure and ICP described in ophthalmodynamometric studies in human [ 20 – 23 ] and animal studies [ 18 , 19 , 108 – 110 ]. Changes in the venous system from raised ICP arises from elevated downstream cerebral venous pressures and external pressure on the subarachnoid segment of the central retinal vein, which increases vascular resistance [ 111 ].…”

A machine learning approach in the non-invasive prediction of intracranial pressure using Modified Photoplethysmography

“…This indicates that ophthalmodynamometry is an important component of our image acquisition methodology. Moreover, the findings are consistent with the high correlation between retinal venous opening pressure and ICP described in ophthalmodynamometric studies in human [ 20 – 23 ] and animal studies [ 18 , 19 , 108 – 110 ]. Changes in the venous system from raised ICP arises from elevated downstream cerebral venous pressures and external pressure on the subarachnoid segment of the central retinal vein, which increases vascular resistance [ 111 ].…”

Non-Invasive Measurement of Intracranial Pressure Through Application of Venous Ophthalmodynamometry

“…These results are shown in Table 1. By comparing Figures 2B and 2C, it can be seen that pulsation occurred consistently after IOP was increased relative to ICP, similar to previous reports [6]. Further testing is required to assess the specific relationship between the magnitude of pulsitility, IOP, and ICP.…”

Retinal Vessel Diameters Change Within 1 Hour of Intracranial Pressure Lowering

“…These effects have been well documented in short-term studies of ICP change within animals and humans, including in the current study. 8 However, the current study did not find differences between individuals at baseline to suggest use of retinal vessel diameters as a clinical marker of baseline ICP. The second is direct tissue pressure exerted by swollen ganglion cell axons on the central retinal vessels to alter their resistance, with resulting effects on retinal vessel pressures and diameters.…”

A machine learning approach in the non-invasive prediction of intracranial pressure using Modified Photoplethysmography

“…This indicates that ophthalmodynamometry is an important component of our image acquisition methodology. Moreover, the findings are consistent with the high correlation between retinal venous opening pressure and ICP described in ophthalmodynamometric studies in human [ 20 – 23 ] and animal studies [ 18 , 19 , 108 – 110 ]. Changes in the venous system from raised ICP arises from elevated downstream cerebral venous pressures and external pressure on the subarachnoid segment of the central retinal vein, which increases vascular resistance [ 111 ].…”

Non-Invasive Measurement of Intracranial Pressure Through Application of Venous Ophthalmodynamometry

“…These results are shown in Table 1. By comparing Figures 2B and 2C, it can be seen that pulsation occurred consistently after IOP was increased relative to ICP, similar to previous reports [6]. Further testing is required to assess the specific relationship between the magnitude of pulsitility, IOP, and ICP.…”

Retinal Vessel Diameters Change Within 1 Hour of Intracranial Pressure Lowering

“…These effects have been well documented in short-term studies of ICP change within animals and humans, including in the current study. 8 However, the current study did not find differences between individuals at baseline to suggest use of retinal vessel diameters as a clinical marker of baseline ICP. The second is direct tissue pressure exerted by swollen ganglion cell axons on the central retinal vessels to alter their resistance, with resulting effects on retinal vessel pressures and diameters.…”

A machine learning approach in the non-invasive prediction of intracranial pressure using Modified Photoplethysmography

“…This indicates that ophthalmodynamometry is an important component of our image acquisition methodology. Moreover, the findings are consistent with the high correlation between retinal venous opening pressure and ICP described in ophthalmodynamometric studies in human [ 20 – 23 ] and animal studies [ 18 , 19 , 108 – 110 ]. Changes in the venous system from raised ICP arises from elevated downstream cerebral venous pressures and external pressure on the subarachnoid segment of the central retinal vein, which increases vascular resistance [ 111 ].…”

Non-Invasive Measurement of Intracranial Pressure Through Application of Venous Ophthalmodynamometry

“…These results are shown in Table 1. By comparing Figures 2B and 2C, it can be seen that pulsation occurred consistently after IOP was increased relative to ICP, similar to previous reports [6]. Further testing is required to assess the specific relationship between the magnitude of pulsitility, IOP, and ICP.…”

Retinal Vessel Diameters Change Within 1 Hour of Intracranial Pressure Lowering

“…These effects have been well documented in short-term studies of ICP change within animals and humans, including in the current study. 8 However, the current study did not find differences between individuals at baseline to suggest use of retinal vessel diameters as a clinical marker of baseline ICP. The second is direct tissue pressure exerted by swollen ganglion cell axons on the central retinal vessels to alter their resistance, with resulting effects on retinal vessel pressures and diameters.…”