Paranasal Sinus CT Scans Analysis of the Primary Maxillary Sinus Hypoplasia

Kim, Yong Dae; Choi, Cheol Gee; Suh, Bo Su; Song, Si Youn; Suh, Jang Su; Song, Kei Won

Abstract

BACKGROUND AND OBJECTIVES: Identification of primary maxillary sinus hypoplasia (PMSH) is important diagnostically and therapeutically. Recently, the clinical significance of associated abnormalities in PMSH has been suggested. The aim of this study is to investigate the incidence of PMSH, their associated abnormalities and relationship of anatomical variations and paranasal sinusitis.
MATERIALS AND METHODS
We evaluated radiologic diagnostic criteria of PMSH and analyzed the relationship of the anatomical variations of nasal cavity and paranasal sinuses in paranasal sinus CT scans, retrospectively. We measured the volume estimated ratio (VER) in PMSH cases.
RESULTS
The incidence of unilateral and bilateral PMSH were 11 cases (5.9%) and 10 cases (5.3%). respectively. According to the Bolger's classification, there were 13 sites (41.9%) of type I with the mean VER of 0.71, 14 sites (45.2%) of type II with the mean VER 0.50, and 4 sites (12.9%) of type III with the mean VER of 0.27. The most common anatomical anomalies in both of the unilateral and bilateral PMSH were zygomatic (90.3%) and alveolar pneumatization (90.3%); the second most common abnormal finding was high maxillary sinus floor (77.4%). Of the anatomical variations, the frequency of uncinate process abnormalities (41.9%), paradoxical middle turbinate (32.3%) and Haller's cell (19.4%) were statistically significant.
CONCLUSION
These results suggest that zygomatic and alveolar pneumatization, and high maxillary sinus floor are additionally important anatomical abnormalities associated with PMSH. Careful preoperative assessment of anatomical variations in the paranasal sinus CT scans may be essential to avoid incidental iatrogenic complications during functional endoscopic sinus surgery (FESS) or Caldwell-Luc operation in patients with PMSH.