How To: Hidden Port Approach to Endoscopic Pericranial Scalp Flap for Anterior Skull Base Reconstruction

by Alfredo García-Fernández, MD, PhD, Esther García-González, MD, Igor Paredes-Sansinenea, MD, PhD, Víctor Rodríguez-Berrocal, MD, José Fernández-Alén, MD, PhD, Alfonso Lagares Gómez-Abascal, MD, PhD, Francisco González-Llanos, MD, PhD, and Nieves Mata-Castro, MD, PhD •

Through this endoscopic approach, glabellar incision can be avoided by performing frontal osteotomy endoscopically.

Subsequently, using a cautery needle with the tip bent at a 45° angle, the pericranium was sectioned following the outline of the previously designed flap and was detached under endoscopic vision until it was pedicled on the left supraorbital and supratrochlear arteries. The previously performed osteotomy was found and its edges were smoothed from the outside with the same 70° bur. The flap was transposed into the nasal cavity through the osteotomy, avoiding the twisting of its pedicle. A DuraGen sheet was placed intradurally. The flap was positioned to cover the defect and bolstered into place with Surgicel and a surgical adhesive. In all patients, light pressure scalp dressing was applied to avoid the risk of hematoma and removed the day after surgery.

RESULTS

In the previous anatomical study, we confirmed the feasibility of performing osteotomy with a 70° bur in the anterior wall of the frontal sinus from within the sinus. Likewise, we found that the same area could be reached endoscopically from a coronal mini-incision using the same bur.

In the clinical study, this completely endoscopic technique allowed total closure of the anterior skull base with the pericranial flap in all patients. None of them developed postoperative cerebrospinal fluid leak or presented symptoms of supraorbital or supratrochlear nerve lesions. The patients were hospitalized for 6 or 7 days after surgery. None of the patients presented with closure of the frontal sinusotomy on the long-term.