Temporal Bone Hyperpneumatization and Tinnitus: Clinico-Radiological Evaluation Using CT Scan

Abstract

Purpose: We propose that there is increased incidence of subjective tinnitus (ST) in patients with temporal bone hyperpneumatization (TBHP). The secondary goal of this project is to assess the degrees of association of TBHP with paranasal sinus hyperpneumatization (PNSHP), chronic sinusitis (CS), otomastoiditis (OM) and concha bullosa (CB). Methods and Materials: A total of 196 patients, who had computed tomography (CT) of the head for various clinical indications, were included in this study. CT head scans of patients with TBHP (n=96) were correlated with control patients (n=100). These patients had no apparent TBHP, history of ST, PNSHP, CS, OM or CB. The TBHP was graded based upon the extent of pneumatization. Size of the maxillary and sphenoid sinuses were also measured, providing pneumatization grade. Results: Subjective tinnitus (ST) was present in 31 cases of TBHP and in 8 patients in the control group, which was statistically significant. Mean volume of maxillary sinus and the largest axial sphenoid sinus diameter were significantly larger in the cases of TBHP than in that of controls. Otomastoiditis was found in only 4 cases of TBHP (4%) and none of the controls; however, the difference was not statistically significant. Chronic sinusitis was present in 8 cases of TBHP and 5 of controls, and was also not statistically significant. Concha bullosa was significantly more frequent among cases of TBHP than controls. Conclusion: There is a significant (p < 0.001) association between subjective tinnitus and increasing grade of temporal bone hyperpneumatization. There is a positive correlation between paranasal sinus hyperpneumatization and occurrence of concha bullosa, mimicking symptoms of sinusitis, with TBHP.