Myospherulosis following sinus surgery: pathological curiosity or important clinical entity?

Myospherulosis is a foreign body reaction to lipid material used on nasal packing at the conclusion of sinus surgery. This reaction has been associated with postoperative adhesion formation. The purpose of the study was to determine whether the occurrence of myospherulosis has an adverse effect on clinical outcome following sinus surgery.

Case-control study at an academic medical center.

Thirty-two cases of myospherulosis were identified in 28 patients (4 with bilateral disease) who underwent sinus surgery between 1989 and 1999. Cases were staged according to histological and radiological grading systems. Clinical outcome was compared with a control group of 28 patients who had similar surgery during the same time period.

Patients with myospherulosis were found to have a significantly higher likelihood of developing postoperative adhesions compared with control subjects (50% vs. 18%, respectively [P =.023]). Histological stage, based on the extent of lipid vacuoles and spherules (erythrocyte remnants) present in the surgical specimen, was found to correlate with disease severity based on preoperative sinus computed tomography staging (P =.009). Patients with myospherulosis tended to have a shorter interval between their last two surgeries than did control subjects (2.2 +/- 2.1 vs. 4.5 +/- 7.1 y, respectively [P =.086]). Patient age, sex, comorbid conditions, CT stage, and number of previous operations were not predictive for the occurrence of myospherulosis.

Patients who develop myospherulosis from lipid-based packing material used during sinus surgery are more likely to form postoperative adhesions. These adhesions appear to be clinically relevant and may hasten the need for revision surgery.