Radiographic Changes of the Nasolacrimal Duct in Silent Sinus Syndrome

Silent sinus syndrome (SSS), known as chronic maxillary atelectasis, is characterized by inward collapse of the maxillary sinus walls with resultant bowing of the maxillary sinus bones due to negative antral pressures. Functional endoscopic sinus surgery (ESS) is an important first step to normalize pressures. The impact of SSS on nasolacrimal duct (NLD) anatomy remains unclear. The study hypothesized that SSS may distort NLD anatomy, since the duct sits within the maxillary bone, and aimed to compare the radiographic changes on the affected and unaffected sides, as well as pre- and post-ESS.

A retrospective review was conducted on patients with computed tomography (CT) face/orbit with radiographic findings of SSS. A subset who underwent ESS with a post-operative CT was included for secondary analysis. The NLD, sinus, and orbit were measured in a standardized fashion. Primary outcome assessed differences between the affected and unaffected sides, while secondary outcomes evaluated pre- and post-ESS changes. Analysis was performed with a paired-t test.

Twenty patients met inclusion criteria, with 12 included in post-ESS analysis. The affected side showed significantly smaller maxillary sinus width and height, and orbit height (p < .001). The distal NLD (lateral) was 0.44 mm larger on the affected side (p = .01), but all other NLD measurements were not significant. No significant changes were observed in NLD, sinus, or orbit measurements after ESS.

SSS did not significantly distort NLD anatomy, nor were there anatomical changes post-ESS, aside from a larger distal NLD on the affected side, possibly due to bowing of the inferior turbinate. Future directions could consider 3-D volumetric analysis of the NLD.