ENDONASAL MICROSCOPICALLY CONTROLLED SURG ERY OF THE FRONTAL-SINUS

Background: The anatomic variation of the frontal sinus and frontal re cess can create both a diagnostic and therapeutic challenge. Most case s of frontal sinus disease can now be treated by endoscopic approaches . For refractory cases or those with severe pathology, the microscopic ally controlled drainage (MCD) operation has at times been successful and spared the patient the morbidity of an external approach. The aim of this study was to evaluate microscopically controlled frontal sinus surgery in these difficult cases. Material and Methods: Prospective a nalysis was performed on the efficacy of MCD in patients for whom endo scopic sinus surgery had failed or in primary cases with severe pathol ogy or unfavorable anatomy. The technique employs a selfretaining endo nasal retractor and a diamond bur under microscopic visualization to r emove solid bone (frontal spine) obstructing the sinus drainage and al low a wide opening of the frontal recess while causing minimal mucosal damage. Unilateral drainage (extended frontal sinus drainage operatio n), and in some cases bilateral drainage (median drainage procedure) i s employed. Results: With an average of 23 months of follow-up, over 9 0% of patients were either free of symptoms or substantially improved after the MCD procedure. Three patients required revision surgery (ext end the opening into a median drainage procedure) for adequate relief of symptoms. Conclusions: The MCD procedure is highly successful in th e treatment of frontal recess disease, particulary in those cases of s evere pathology or difficult anatomy. It may be used in those cases re fractory to standard endoscopic sinus surgery where an external approa ch and frontal sinus obliteration are contempated. As with endoscopic sinus surgery, precise knowledge of the frontal recess and neighboring landmarks is critical, and adequate drainage with minimal mucosal dis ruption should be the goal.