Radiological Feasibility of the Endoscopic Transnasal Prelacrimal Recess Approach.

BACKGROUND: Prelacrimal recess (PLR) distance, medial wall thickness, and the internal angle of the pyriform notch (APN) have been suggested by various studies as assessment metrics to determine the feasibility and intraoperative difficulty of the transnasal prelacrimal recess approach (TPRA), with ethnic variations. OBJECTIVE: To assess the computed tomography (CT) scan feasibility of endoscopic TPRA in healthy and diseased paranasal sinuses. METHODS: Our sample consisted of 750 adults (1,500 sides) who had CT of the nose and paranasal sinuses (PNS) for various indications. The CT scans were analyzed to assess variations in the distance, thickness, and angle of the prelacrimal recess on both sides concerning different demographic parameters (age and gender). All parameters were grouped into low, median, or high radiological feasibility of TPRA. RESULTS: There was no difference in feasibility parameters between 546 healthy PNS (72.8%) and 204 chronic rhinosinusitis cases (27.2%). Only 2.7% of the maxillary sinuses studied (1,500 sides) had high radiological feasibility, 53.1% had medium radiological feasibility, and 44.2% had low radiological feasibility for TPRA. Males and individuals younger than 30 years of age had a significantly greater distance and thinner walls, making the sinus more surgically accessible ( p  < 0.05). CONCLUSION: The three parameters studied can be collectively applied to the preoperative assessment of patients subjected to TPRA with no effect of inflammation on accessibility parameters. Difficult accessibility can be anticipated in 42% of the population, so surgeons must have caution when practicing TPRA.