The state of the frontal sinus after craniotomy.

In 39 patients, 24 male, 15 female, the frontal sinus was opened during a frontal, a bifrontal or a pterional trephination for neurosurgical treatment of trauma, tumours or aneurysms. In 25 out of 39 patients the frontal sinus subsequently was obliterated, in 11 out of 39 patients the apical half or 2/3 of the sinus were ablated and the remaining caudal part covered with a galea periosteal flap leaving the fronto-nasal duct intact. In 3 out of 39 patients, the periphery of the sinus was ablated and the remaining part covered. All patients were followed over a mean period of 2 years and had a final evaluation using CTs, X-rays, ultrasonography and a complete ENT examination. In 4 out of 25 obliteration was successful and complete, in 16 out of 25 there was a partial or complete re-aeration of the residual sinus and in 5 out of 25 the sinus was infected. In one out of eleven patients where the frontal sinus was bisected with preservation of the lower half, the basal part of the sinus was infected, in 10 out of 11 the residual sinus was aerated and draining well. In one out of three patients where the periphery of the sinus was ablated, there was infection, two of three sinuses were aerated. Evaluating the experience in these 39 patients and our recent experience, obliteration of the sinus with muscle is very unreliable and the use of bone wax is obsolete. Covering a bisected or peripherally opened sinus with fascia or a galea periosteal flap will yield a well aerated and draining sinus, provided the naso-frontal duct is intact.