Thickness and texture of the squamous temporal bone in a Nigerian tertiary hospital

Background: Thickness and texture of the squamous temporal bones (STBs) are the two main patient factors that determine the outcome of transtemporal transcranial Doppler ultrasound. The aim of this study was to determine the thickness and texture of the STB as well as their association with biodemographic characteristics in a tertiary hospital in Southwest Nigeria. Material and Methods: Cranial computed tomography (CT) images of 142 adults acquired on a 64-slice multi-detector Toshiba Aquilion scanner were retrospectively evaluated for the thickness and texture of the bilateral STB at the expected location of the temporal acoustic window on a ClearCanvas® Workstation. Associations of thickness and texture of the STB with biodemographic data were determined by statistical analysis at P < 0.05. Results: There were 79 male (55.6%) participants and the overall mean age was 51 ± 17.3 years (49 ± 16.1 years in males and 53.4 ± 18.5 years in females). Mean thickness of the 284 STB was 3.21 ± 1.11 mm (range 1.2–8.7 mm), which was thicker on the left (3.3 ± 1.2 mm) than the right (3.1 ± 1.0 mm, P = 0.001). Thickness of STB showed significant increase (P < 0.05) with age on the right (β = 0.23) and left (β = 0.31). Controlling for age, males tend to have thicker STB than females. Thicknesses of STB in 61.3% were favorable for transcranial insonation bilaterally. Homogenous texture was found in 64.8% of STB while the rest were heterogeneous. A combination of both thickness and texture appear favorable for transcranial insonation in 76.8% of STB evaluated. Conclusion: Thickness of the squamous temporal bone varied significantly with age but not with gender, and the temporal squama were largely of a homogeneous texture. Overall, the important patient factors appear favorable for transtemporal cranial ultrasound in the majority of our participants.