Factors affecting transtemporal window quality in transcranial sonography

Objective To assess the influencing factors of transtemporal window quality and identify patients suitable for transcranial sonography (TCS) examination in two-dimensional imaging. Methods In this cross-sectional study, TCS was performed in 161 consecutive patients through the temporal bone window (TBW) in the neurology or neurosurgery department. Each patient's sex, age, height, weight, and temporal bone thickness (TBT) were collected. After examination, the patients were divided into two groups: TBW success and TBW failure. The data were statistically compared between the two groups. Results Among the studied population, the total TBW success rate was 80.1% (95% confidence interval [CI]: 74-86). The TBW success rate was 91.4% (95% CI: 85-98) in males and 70.9% (95% CI: 61-81) in females (p = .001). Sex (p = .001), age (p = .002), height (p = .047), and TBT (p < .001) showed significant differences between the TBW success and failure groups. In males, only TBT (p = .001) showed a significant difference; in females, age (p < .001) and TBT (p = .003) showed a significant difference. The area under the receiver operating characteristic curve (AUC) of sex, age, and TBT and their combination was 0.686, 0.659, 0.842, and 0.922 (p < .001), respectively. The AUC of the combination of parameters was significantly greater than that of age and sex alone (p = .007; p = .0002) but not greater than that of TBT (p = .090). Conclusions The TBW success rate varied with sex, age, height, and TBT. Males, younger patients, taller patients, and patients with a thinner temporal bone tended to be more suitable for the examination by TCS.