Magnetic resonance imaging study of incidental findings in the paranasal sinuses and ostiomeatal complex

Inflammatory Modifications in Paranasal Sinuses and Ostiomeatal Complex Anatomical Variations in Jet Aircraft Pilots: A Computed Tomography Study

Introduction  Jet aircraft pilots are exposed to huge pressure variation during flight, which affect physiological functions as systems, such as the respiratory system. Objectives  The objective of the present investigation was to evaluate inflammatory changes of paranasal sinuses of jet aircraft pilots before and after a jet aircraft training program, using multislice computed tomography (CT), in comparison with a group of nonairborne individuals with the same age, sex, and physical health conditions. A second objective of the present study was to assess the association between the ostiomeatal complex obstruction and its anatomical variations. Methods  The study group consisted of 15 jet aircraft pilots participating in the training program. The control group consisted of 41 nonairborne young adults. The 15 fighter pilots were evaluated before initiating the training program and after their final approval for the presence of inflammatory paranasal sinus disease. The ostiomeatal complex anatomical variations and obstructions were analyzed in pilots after the training program. Results  Jet aircraft pilots presented higher incidence of mucosal thickening in maxillary sinus and anterior ethmoid cells than controls. Prominent ethmoidal bulla showed significant association with obstruction of the osteomeatal complex. Conclusions  Jet aircraft pilots present increased inflammatory disease when compared with nonairborne individuals. The presence of a prominent ethmoidal bulla is associated with ostiomeatal complex obstruction.

The Influence of Nonaerated Paranasal Sinuses on DTI Parameters of the Brain in 6- to 9-Year-Old Children

BACKGROUND AND PURPOSE

DTI is prone to susceptibility artifacts. Air in the paranasal sinuses can cause field inhomogeneity, thus affecting measurements. Children often have mucus in their sinuses or no pneumatization of them. This study investigated the influence of lack of air in the paranasal sinuses on measurements of WM diffusion characteristics.

MATERIALS AND METHODS

The study was embedded in the Generation R Study, a prospective population-based birth cohort in Rotterdam (the Netherlands). Brain MR imaging studies (1070 children, 6-9 years of age) were evaluated for mucosal thickening of the paranasal sinuses. Nonaeration of the paranasal sinuses (modified Lund-Mackay score) was compared with that in a randomly selected control group. The relationship between nonaerated paranasal sinuses and fractional anisotropy and mean diffusivity in the DTI fiber tracts was evaluated using ANCOVA and independent t tests.

RESULTS

The prevalence of mucosal thickening was 10.2% (109/1070). The mean modified Lund-Mackay score was 6.87 (SD, 3.76). In 52.3% (57/109), ≥ 1 paranasal sinus was not pneumatized. The results are reported in effect sizes (Cohen's d). Lower mean fractional anisotropy values were found in the uncinate fasciculus (right uncinate fasciculus/right frontal sinus, d = -0.60), superior longitudinal fasciculus (right superior longitudinal fasciculus/right ethmoid sinus, d = -0.56; right superior longitudinal fasciculus/right sphenoid sinus, d = -2.09), and cingulate bundle (right cingulum bundle/right sphenoid sinus, d = -1.28; left cingulum bundle/left sphenoid sinus, d = -1.49). Higher mean diffusivity values were found in the forceps major/right and left sphenoid sinuses, d = 0.78.

CONCLUSIONS

Nonaeration of the paranasal sinuses is a common incidental finding on pediatric MR imaging brain scans. The amount of air in the paranasal sinuses can influence fractional anisotropy and, to a lesser degree, mean diffusivity values of WM tracts and should be considered in DTI studies in pediatric populations.

Assessment of factors influencing the olfactory bulb volume in patients with post-viral olfactory dysfunction

PURPOSE

To investigate the factors influencing the volume of the olfactory bulb (OB) in patients with post-viral olfactory dysfunction (PVOD).

METHODS

We collected 92 olfactory bulb volumes from patients with PVOD who underwent a sinus computed tomographic and magnetic resonance imaging (MRI) scan of the head and collected clinical information including gender, age, disease course, minimal cross-sectional area, nasal airway resistance, and olfactory function. OB volume was measured in MRI and the scans were evaluated according to the Lund-Mackay (LM) scoring system.

RESULTS

Male patients with PVOD had a larger OB volume (β = 0.284, P < 0.05). OB volume was smaller in patients with a longer course of olfactory dysfunction (β = - 0.254, P < 0.05). According to the LM scoring system, patients with a higher anterior ethmoidal sinus score had smaller OB volume (β = - 0.476, P < 0.05).

CONCLUSIONS

The study revealed that gender, disease course, and the score of anterior ethmoidal sinusitis can affect the OB volume in patients with PVOD.