## 3 Results  
Thirty-one patients with complaints of subjective tinnitus and twenty-four healthy control individuals matched for age and sex were enrolled in this prospective study. The case group consisted of 11 males and 20 females, aged 26 to 73 years (mean: 50.42 \(\pm\) 9.64 years), while the control group included 12 males and 12 females, aged 24 to 58 years (mean: 39.67 \(\pm\) 10.63 years). There was no statistically significant difference between the groups in terms of gender distribution (\(p>0.05\)). Baseline characteristics, including mean age, sex, pure tone audiometry (PTA), lipid profile, fasting glucose levels, systolic blood pressure (SBP), and diastolic blood pressure (DBP), were measured in both groups. Lipid profiles revealed statistically significant differences in cholesterol, triglyceride, and low-density lipoprotein (LDL) levels between the case and control groups (\(p<0.05\)). However, SBP and DBP values were similar between the groups, with no statistically significant differences observed (case group: SBP 116.48 \(\pm\) 8.28, DBP 76.12 \(\pm\) 3.58; control group: SBP 112.56 \(\pm\) 5.8, DBP 75.15 \(\pm\) 4.72; \(p>0.05\)) (Table 1). Vascular parameters assessed via vertebral Doppler ultrasonography, including vertebral artery stiffness (VAS), pulsatility index (PI), and resistive index (RI), are summarized in Table 2. Stiffness levels and PI values were significantly higher in the case \begin{table}
\begin{tabular}{l l l l} \hline  & **Case (\(n\) = 31)** & **Control (\(n\) = 24)** & \(p\) **Value** \\ \hline Age & 50 \(\pm\) 9.64 & 46.6 \(\pm\) 10.63 & 0.188 \\ Gender (Female/Male) & 20/11 & 12/12 & 0.279 \\ PTA (dB) Right & 22.16 \(\pm\) 13.8 & 20.3 \(\pm\) 7.3 & 0.585 \\ (dB) Left & 21.9 \(\pm\) 9.4 & 20 \(\pm\) 5.3 & 0.838 \\ HDL (mg/dL) & 47.2 \(\pm\) 11.6 & 49.3 \(\pm\) 7 & 0.453 \\ LDL (mg/dL) & 149.4 \(\pm\) 37.9 & 106.1 \(\pm\) 10.7 & \(<\)0.005 \\ TG (mg/dL) & 202.2 \(\pm\) 83.5 & 148.6 \(\pm\) 26.4 & \(<\)0.005 \\ Fasting Glucose (mg/dL) & 82.5 \(\pm\) 7.4 & 80.5 \(\pm\) 5.5 & 0.310 \\ Cholesterol (mg/dL) & 193.6 \(\pm\) 47.28 & 167.5 \(\pm\) 28.99 & 0.021 \\ SBP (mmHg) & 116.48 \(\pm\) 8.28 & 112.56 \(\pm\) 5.8 & 0.380 \\ DBP (mmHg) & 76.12 \(\pm\) 3.58 & 75.15 \(\pm\) 4.72 & 0.160 \\ \hline \end{tabular}
\end{table} 
Table 1: Demographic variables and blood sample data of the control and case groups. group compared to the control group (_p_ < 0.05). Specifically, VAS values for the left and right vertebral arteries were 2.87 \(\pm\) 0.72 and 2.99 \(\pm\) 0.77, respectively, in the case group, versus 2.12 \(\pm\) 0.22 and 2.14 \(\pm\) 0.5 in the control group. Similarly, PI values for the left and right vertebral arteries were 2.45 \(\pm\) 1.2 and 2.49 \(\pm\) 1.02, respectively, in the case group, compared to 1.2 \(\pm\) 0.43 and 1.19 \(\pm\) 0.42 in the control group. There were no significant differences in vertebral artery diameters between the groups (case group: left 0.39 \(\pm\) 0.08, right 0.38 \(\pm\) 0.085; control group: left 0.38 \(\pm\) 0.08, right 0.38 \(\pm\) 0.03) (Table 2). Vertebral artery vascular structural patterns between case and control groups. Vertebral artery stiffness Left 2.87 \(\pm\) 0.72 2.12 \(\pm\) 0.22 \(<\)0.005  
Vertebral artery stiffness Right 2.99 \(\pm\) 0.77 2.14 \(\pm\) 0.5 \(<\)0.005  
Vertebral artery RI Left 0.86 \(\pm\) 0.32 0.94 \(\pm\) 0.24 0.581  
Vertebral artery RI Right 0.84 \(\pm\) 0.31 0.91 \(\pm\) 0.22 0.509  
Vertebral artery PI Left 2.45 \(\pm\) 1.2 1.2 \(\pm\) 0.43 \(<\)0.005  
Vertebral artery PI Right 2.49 \(\pm\) 1.02 1.19 \(\pm\) 0.42 \(<\)0.005  
Rl: Resistive index, PI: Pulsatility index. Vertebral artery vascular parameters and the side of tinnitus were shown in Table 3. Of the tinnitus patients, 11 (35%) reported bilateral tinnitus, 11 (35%) reported tinnitus localized to the left side, and 9 (30%) reported right-sided tinnitus. Tinnitus was more frequently observed on the side with reduced blood supply from the vertebral artery. Table 3 details the VAS, PI, and RI values according to the side of tinnitus.