Management of Intratemporal Facial Nerve Injuries

Objective: Outcomes of facial nerve (FN) restoration and decompression in patients with total loss of FN function after temporal bone fracture were analyzed.

Material: Seventeen patients underwent FN exploration in the labyrinthine segment of the facial canal between the years of 1983 and 2007. Decompression of the FN through the middle cranial fossa approach was performed in 12 patients. Surgical exploration was combined with free nerve grafts in five patients with total disruption of FN continuity. The causes of injury were: five patients had mine-blast trauma, three fell from a high place, and nine had been in a motor-vehicle accident. Transverse petrosal fracture was found in eight cases, and nine had longitudinal fracture. Temporal bone fracture conjoined with carotid-cavernous fistula in two patients. Cerebrospinal fluid (CFS) leakage was observed in 11 cases: The CFS fistulas closed spontaneously in nine patients, and three patients underwent CFS fistula closure using a free fat graft. Preoperative electrophysiological testing demonstrated total facial muscle denervation. The House-Brackmann (HB) grading scale was used to evaluate FN functions. The interval between FN injury and surgery ranged from 2 to 30 days (mean, 17.4 days).

Results: Intraoperative findings: FN injury in the labyrinthine segment was observed in all 17 cases. Five patients underwent FN transection, and we used nerve graft for FN repair. We found bone impingement and hematoma in nine cases, FN edema was identified in three patients. All patients had complete unilateral facial paralysis and an HB score of VI on presentation. Average follow-up was a minimum of 1 year. Among patients with FN decompression according to HB scale, two patients (16.7% ) achieved HB I, two (16.7%) had HB II, six (50%) had HB III, one (8.3 %) had HB IV, and one (8.3%) had HB V. In the group where nerve graft was used, two patients achieved HB II, and three had HB III.

Conclusion: In total loss of FN function, early decompression is indicated for the best functional result. Early nerve graft for nerve repair gives good results. A combination of FN exploration and CFS fistula closure is reasonable.