Orbital complications of infected mucocele in the paranasal sinuses

Objective: Infected mucocele of the paranasal sinuses can induce orbital infection, including orbital subperiosteal abscess, which may lead to life-threatening intracranial complications. Effective diagnosis is important, and treatment should be aggressive. This paper presents our experiences in endoscopic surgical management of orbital complications secondary to infected paranasal sinus mucoceles. Methods: From our retrospective review of the medical charts for 82 patients with 92 sides diagnosed with paranasal sinus mucoceles, we present 7 sides in 7 adult patients with orbital complications secondary to infected mucoceles. The collected data include the suggested etiology, side of sinus involvement, localization of abscess in the orbit, orbital wall bone defects caused by mucocele compression, ophthalmic symptoms, duration between symptom onset and initial visit, operation date, type of surgery performed, and follow-up. Results: The mucocele was located in the ethmoid-frontal region in 9.8% of the sides (9/92), in the frontal sinus in 7.6% (7/92), in the ethmoidal sinus in 9.8% (9/92), in the maxillary sinus in 67.4% (62/92), in the maxillary-ethmoidal sinus in 3.3% (3/92), and in the sphenoid sinus in 2.2% (2/92). The patients with ethmoid-frontal mucoceles had a significantly higher incidence of orbital complications (6/9) as compared with the other sub-types of mucoceles (frontal, 0/7; ethmoidal, 0/9; maxillary, 1/62; maxillary-ethmoidal, 0/3; sphenoid, 0/2). Chandler's classification showed Type I in one, Type II in three, and Type III in three. Sinus involvement was observed at the ethmoid-frontal sinuses in six cases and the maxillary sinus in one case. All seven cases had a partial defect of the orbital wall bone (lamina papyracea, or inferior orbital wall bone) by mucocele compression, and the patients underwent endoscopic marsupialization. For the cases with subperiosteal abscess, the lamina papyracea was also removed partially for draining the abscess. In all cases, symptoms were resolved without any recurrence of the mucocele. Conclusions: Infected ethmoid-frontal mucoceles with a defect of the lamina papyracea tend to induce orbital infection, so prompt surgery for the infected mucoceles should be considered early even with Types I and II, before visual acuity is impaired, because surgery is the only curative treatment for the mucoceles.