B-MODE ULTRASONOGRAPHY OF THE PARANASAL SINUSES IN COMPARISON TO COMPUTED-TOMOGRAPHY

Background: In diagnostic imaging of the paranasal sinuses, the A-mode technique is increasingly being substituted by B-mode ultrasonography . To assess the value of B-mode sonography we compared in a double-bli nd study computed tomography with our ultrasound findings. Patients an d Methods: Seventy-eight patients were examined by CT and subsequently by ultrasound, two-thirds before endonasal surgery and one-third for diagnosis of serious facial pain and swelling. Results: Among 114 path ological maxillary sinus tomograms, 83 findings could also be diagnose d by ultrasound (sensitivity 72.8%). In the frontal sinuses only 12 of 52 of pathological findings could be detected (23.1%) and only 9 of 8 0 in the frontal ethmoid (11.3%). Except for circumscribed polyps and moderate general swelling of the mucosa, the detection rate by sonogra phy was 97.4% for the maxillary sinuses, 31.5% for the frontal and 18% for the ethmoid sinuses. Conclusions: Ultrasound usually only demonst rates the presence of absence or unspecific findings. Differential dia gnosis between tumors and sinusitis is generally difficult. The health y individual is correctly assessed as healthy due to the total reflect ion of the air-filled healthy sinus. According to our findings ultraso und has a certain value in the diagnosis of maxillary sinuses. It can be used to obtain a preliminary diagnosis and as a screening method al though a negative result never excludes a disease of the sinuses. As i t does not involve radiation exposure, ultrasonography can be recommen ded as first step in diagnosis for children, pregnant women, and young women especially in acute sinusitis, because in acute sinusitis the m axillary sinuses are generally affected.