Study on the correlation between hemodynamic status of the transverse sinus-sigmoid sinus and the clinical efficacy of sigmoid sinus wall reconstruction

Background and Purpose For patients with pulsatile tinnitus who have both transverse sinus stenosis and sigmoid sinus wall anomalies, sigmoid sinus wall reconstruction surgery is the first-choice treatment when the trans-stenotic pressure gradient less than 10 mmHg. However, not all patients are cured by surgery. We hypothesized the abnormal hemodynamics caused by transverse sinus stenosis is associated with the clinical efficacy of surgery. Methods Eight pulsatile tinnitus patients treated with surgery were retrospectively reviewed (4 rehabilitated, 4 nonrehabilitated). All patients had radiologically diagnosed transverse sinus stenosis and sigmoid sinus wall anomalies. A numerical simulation of the hemodynamics of the transverse sinus-sigmoid sinus was performed using computational fluid dynamics technology. Changes in the blood flow patterns before and after surgery were observed. The blood flow velocity at the stenosis, vorticity of blood flow in the sigmoid sinus and wall pressure distribution in the sigmoid sinus wall anomalies area were compared. Results The blood flow velocity in the stenosis (preoperative P = 0.04, postoperative P = 0.004) and vorticity in the sigmoid sinus (preoperative P = 0.02, postoperative P = 0.007) pre- and post-surgery were significantly higher in the non-rehabilitation group than in the rehabilitation group. No significant difference was found in the wall pressure distribution in the sigmoid sinus wall anomalies area (preoperative P = 0.12, postoperative P = 0.24). Conclusions There is a clear correlation between the abnormal hemodynamic status caused by transverse sinus stenosis and the clinical efficacy of surgery. The blood flow velocity at the stenosis and vorticity of blood flow in the sigmoid sinus are factors influencing the clinical efficacy of surgery.