Reliability of ultrasound scan compared to computed tomographic scan in the diagnosis of maxillary sinusitis: A cross-sectional analytical study
Introduction: Sinusitis is an inflammation of paranasal sinus mucosa caused by a viral, bacterial or fungal infection, with the maxillary sinus being the most commonly involved paranasal sinus. Computed Tomography (CT) scan may be the ideal method of diagnosis of maxillary sinusitis, but in Nigeria and other less developed countries, CT scan is not readily available and is expensive. Ultrasonography is rapid, cheap, convenient, non-invasive and readily available. However, the reliability of ultrasonography is required to be evaluated in the diagnosis of maxillary sinusitis.
Aim: was to evaluate the reliability, sensitivity, specificity, positive and negative predictive values of ultrasound scan compared with CT scan in the diagnosis of maxillary sinusitis.
Materials and Methods: A cross-sectional analytical study of randomly selected patients with a clinical diagnosis of rhinosinusitis. Informed consent was obtained. All eligible patients had maxillary sinus ultrasound and CT scans performed. The findings were recorded, and the data was analysed. The Cohen’s kappa reliability test was conducted, and the sensitivity, specificity, positive and negative predictive values were calculated.
Results: There were 100 participants comprised of 53 (53.0%) males and 47 (47.0%) females, within the age range of 13 – 69 years. Of 200 sinuses studied, ultrasound and CT scans showed 39% and 45% abnormal findings, respectively. A comparison between ultrasound scan and CT scan (as a gold standard) showed that the ultrasound scan had sensitivity, specificity and positive and negative predictive values of 82.7%, 65.6%, 74.6%, and 75.6%, respectively. A Cohen’s kappa reliability test showed a moderate agreement between ultrasound and CT scans with k = 0.489 and p < 0.001.
Conclusion: This study showed that sinus ultrasound is reliable with moderate kappa agreement and good sensitivity, specificity, positive and negative predictive values when compared with CT scan. Therefore, ultrasound can be considered as a first-line imaging modality in the diagnosis of maxillary sinusitis.
Keywords: CT scan, Maxillary sinusitis, Predictive values, Reliability, Rhinosinusitis, Sensitivity, Specificity, Ultrasound scan.
