Effect of Maxillary Sinus Pneumatization on the Ease of Access to Prelacrimal Recess.

Objective: Prelacrimal recess approach can be used to access lesions of the anterior wall of the maxillary sinus (MS). Moreover, the longer the prelacrimal recess window distance (PLRWD), the easier it is to access the anterior wall. This study aimed to define the correlation between maxillary sinus pneumatization (MSP) and PLRWD, a previously defined anatomic factor predictive of the ease of prelacrimal recess approach (PLRA).

Methods: In total, 506 sides of 253 participants were studied. In the axial image, the PLRWD, the distance between the anterior wall of the MS and the lacrimal duct, was measured through radioanatomical analysis and classified as type I (<3 mm), type II (3-7 mm), or type III (>7 mm). On the coronal image, the distance between the nasal floor and the lower end of the MS was measured. When MSP did not reach the nasal floor, it was classified as grade I, as grade II when MSP reached the nasal floor, and grade III when the MS was pneumatized below the nasal floor.

Results: Type I included 115 sides (22.7%); type II, 277 sides (54.7%); and type III, 114 sides (22.5%). Grade I was observed in 58 sides (11.5%), grade II in 38 sides (7.5%), and grade III in 410 sides (81.0%). The mean PLRWD of grade I was 2.35 ± 2.41 mm, II was 3.37 ± 2.46 mm, and III was 5.55 ± 2.54 mm, showing a significant difference (P < .001). Post hoc analysis showed significant differences in the mean PLRWD among grades I, II, and III. Two anatomical factors, the MSP and PLRWD, were positively correlated (r = .507, P < .001).

Conclusions: This study demonstrates a correlation between the feasibility of MSP and PLRA. Both MSP and PLRWD are essential diagnostic parameters for preoperative planning and better surgical outcomes.