Jugular valve function and petrosal sinuses pressure: a computational model applied to sudden sensorineural hearing loss

Reports of extra-cranial venous outflow disturbances have recently been linked to sudden sensorineural hearing loss (SSNHL). Aims of the present study are: i) to quantify, with mathematical model, the impact of jugular valve function on the pressure of the superior and inferior petrosal sinuses (SPS, IPS) and the main auricolar veins; ii) to verify the feasibility of the application of mathematical model in the clinical setting in terms of consistency respect to the usual measures of SSNHL outcome. Extra-cranial venous outflow and post analysis were respectively blindly assessed by echo colour-Doppler (ECD) and a validated mathematical model for the human circulation. The pilot study was conducted on 1 healthy control and in a group of 4 patients with different outcome of SSNHL. The main finding was the significant increased pressure calculated in the SPS and IPS of patients with ipsilateral jugular obstruction due to not mobile valve leaflets (6.55 mmHg), respect to the other subjects without extracranial complete obstruction (6.01 mmHg), P=0.0006. Moreover, we demonstrated an inverted correlation between the extrapolated pressure values in the SPS/IPS and the mean flow measured in the correspondent internal jugular vein (r= –0.87773; r-squared= 0.7697; P=0.0009). The proposed mathematical model can be applied to venous extra-cranial ECD investigation in order to derive novel clinical information on the drainage of the inner ear. Such clinical information seems to provide coherent parameters potentially capable to drive the prognosis. This innovative approach was proven to be feasible by the present pilot investigation and warrants further studies with an increased sample of patients.