Abstract
Background/Objectives: The failure rate of minimally invasive surgical approaches to parotid stones is about 10%, primarily due to the presence of large, impacted, or unpalpable deep stones. When stones are palpable and exceed 7 mm in size, a combined transfacial and sialendoscopic approach offers a safe and effective surgical option, while unpalpable and impacted stones located in the parenchyma, not visible or accessible through sialendoscopy, can be treated with a CT-guided transfacial approach. Methods: Twenty-two patients (three females, mean age 53 years, range 32-73 years) underwent CT navigation-assisted transfacial removal of unpalpable and impacted parotid stones at the Department of Otolaryngology and Head and Neck Surgery of Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico of Milan between 2017 and 2024. Results: The mean size of the stones was 7.4 mm (range 4-14 mm), while the mean depth of stones, calculated as the distance from the skin surface, was 8.7 mm (range 4-14 mm). Stones were removed successfully in all but five patients (77% success rate). Failure of the procedure was significantly associated (p < 0.05) with the depth of the stone (>12 mm); in all these cases, patients were treated immediately by means of traditional parotidectomy. Conclusions: The CT-navigation-assisted transfacial approach can be considered a safe, reliable, and efficacious option for the treatment of difficult unpalpable parotid stones, impacted and deeply located in the gland parenchyma. Stones deeper than 10 mm can be more effectively treated by means of traditional parotidectomy if extracorporeal lithotripsy is not available.