Frontoethmoidal sinusitis

If treated promptly with antibiotics and topical nasal decongestants this type of sinus infection is unlikely to be a long-term problem. If allowed to persist chronic frontoethmoiditis gives rise to mucopurulent catarrh, frontal headaches, pressure feeling between the eyes, nasal obstruction and hyposmia. Nasal endoscopy will confirm pus issuing from the middle meatus. The ethmoid sinuses can only be properly assessed radiologically by CT scanning, including coronal as well as axial sections. If frontoethmoiditis fails to settle with conservative treatment then frontal drainage may be required. The frontal sinus is entered through its anterior wall via a small incision below the medial end of the eyebrow. After pus is drained a small sialastic tube is left in the wound to allow regular irrigation of the sinus. Where the disease is more extensive intranasal endoscopic ethmoidectomy may be required. Removal of the uncinate process provides access to the osteomeatal complex, so that if necessary the entire ethmoid complex can be cleared and the frontonasal recess opened. If endoscopic nasal equipment is not available then the tried and tested radical external ethmoidectomy through a Lynch—Howarth incision provides excellent access to the frontal, ethmoid and sphenoid sinuses. Chronic frontal sinus disease can be cleared by means of an osteoplastic flap pro­cedure. Using an X-ray template, the boundaries of the frontal sinus are marked out and a fissure burr is used to cut through the frontal bone along the outline of the sinus. The front wall of the sinus is then prised downwards and for­wards to produce an inferiorly based osteoplastic flap. The diseased lining can then be removed and the sinus obliterated with fat taken from the anterior abdominal wall.

Complications of frontoethmoiditis

These are potentially extremely serious. Quite often infection can spread to involve the other sinuses because of the close proximity of their ostia. Orbital cellulitis is not an uncommon complication (Fig. 39.23) and may progress to an extra periosteal abscess, which typically displaces the eyeball down forwards and laterally. If unrecognised and untreated this can lead to blindness. Treatment consists of intravenous broad-spectrum antibiotic and an orbital decompression by an exter­nal approach. Orbital cellulitis may progress to cavernous sinus thrombosis and septicaemia. Spread of infection by direct bone penetration or via the diploic veins can give rise to either extradural, subdural or frontal lobe abscess formation.

Frontoethmoidal sinusitis summary

  May require open surgical drainage

Chronic frontal sinusitis may require obliterative osteoplastic flap procedure

Orbital complications may threaten sight

  Intracranial complications include cerebral abscess and cavernous sinus thrombosis