Frontal sinus drillout (modified Lothrop procedure): long-term results in 204 patients

Objectives/hypothesis: To determine the long-term results of frontal sinus drillout (also known as modified Lothrop procedure) for the treatment of advanced frontal sinus disease.

Study design: Retrospective review.

Methods: The records of patients who underwent frontal sinus drillout by a single surgeon at an academic medical center from June 1995 through November 2011 were reviewed. Patient demographics and perioperative clinical findings were analyzed for their impact on surgical outcome. Failure was defined as restenosis of the frontal drainage pathways, necessitating additional frontal sinus surgery.

Results: A total of 204 patients underwent frontal drillout surgery (143 bilateral procedures) over the 16-year period. Mean follow-up was 10.2 years (range 0.9-17 years). Symptomatic re-obstruction of the frontal sinus requiring revision surgery occurred in 61 (29.9%) patients. Drillouts performed for a diagnosis of mucocele or tumor had significantly higher failure rate (38.9%, odds ratio [OR] = 2.9, P = 0.022 and 58.3%, OR = 5.3, P = 0.020, respectively). The majority of surgical failures (61%) occurred within 2 years of surgery, but delayed failures were observed up to 12 years after drillout. Clinical outcome did not correlate with a history of smoking, asthma, nasal allergy, aspirin sensitivity, prior sinus surgery, nasal polyposis, or the presence of eosinophilic mucin.

Conclusion: For the majority of patients who undergo frontal sinus drillout, patency of the frontal sinus outflow tract appears to be maintained for more than a decade; nevertheless, almost one-third of patients who undergo this procedure will ultimately require additional frontal sinus surgery.