Dr. Isam Alobid.
Septal perforation repair with pericranial flap
- – At the beginning of surgery the nasal cavity is decongested with cottonoids impregnated with a solution of adrenalin 0.001% with lidocaine 2%. This aids with haemostasis throughout the surgery. The edges of the septal perforation are refreshed in order to improve their binding to the flap.
- – To introduce the pericranial flap into the nasal cavity an osteotomy of frontal sinus is needed which requires a Draf III frontal sinusotomy, as described previously by Draf et al. in 1991. This procedure involves removal of the interfrontal septum, the superior part of the nasal septum, and the frontal sinus floor until the orbit laterally.
- – A standard coronal incision at the vertex of the scalp is made in order to start harvesting the pericranial flap. It would be advisable to be careful with the superficial temporal artery. This artery runs 16.68 mm in front of the tragus and divides into frontal and temporal branches above the zygomatic arch in 74% of specimens.
- – It is important to make the incision from one ear to the other to improve the mobility of the superficial layers of the scalp and facilitate the harvest of the pericranial flap and help its introduction into the nasal cavity. At the level of the temporal line the incision has to continue down until the superficial layer of the deep temporal fascia, which is continuous with the periosteal layer of the cranium.
- – If additional length of the pericranial flap posterior to the coronal incision is needed, care must be taken in making the coronal incision to insure that the pericranium is not divided. Extend the incision down between galeal layer and loose areolar tissue and identify this plane of dissection.
- – Scalp incisions can be made using electrocautery, which is associated with decreased operative times and reduced blood loss, and without increased complications such as alopecia, infection and dehiscence of the incisions.
- – Dissect down along the skull and elevate the galeal fascia and the subcutaneous tissue anteriorly. This dissection is superficial to the loose areolar tissue that is a component of the pericranial flap.
- – As it is explained in the section of anatomy, one must be careful at the level of the orbital rim because the deep branches of the SO and the ST arteries could arise from these main trunks 1cm above the orbital rim. To prevent injury of these neurovascular pedicles, it is highly recommended that dissecting the first centimetre above the orbital rim is avoided.
- – Posteriorly the periostium is incised according to the tissue required for a complete closure of septal perforation. Laterally it is incised along the temporal lines. Later on, the pericranial flap is elevated to approximately 1 cm above the supraorbital rims. Care must be taken not to damage the deep branches of the supraorbital and supratrochlear arteries, as previously explained.
- – The flap is folded back on itself, in its most distal area, for greater thickness of new nasal septum, suturing with dissolvable stitches.
- – The upper margin of the frontal sinus was localized through sinus transillumination, then; the anterior plate of the upper portion of the frontal sinus was drilled to ensure a 30mm width and 10mm height frontal osteotomy. We recommend not making a small osteotomy to avoid causing vascularity problems in the flap in its introduction.
- – With an endoscopic view, the pericranial flap would be introduced into the nasal cavity through the osteotomy of the frontal sinus and rotated laterally 90 degrees to be in a sagittal plane like the nasal septum. Before that, it would be advisable to mark the extremes of the flap with stitches to facilitate insertion into the nasal.
- – The flap is sutured anteriorly to the edge of the perforation and inferiorly to the mucosa of the floor of the nasal cavity with absorbable stitches. In its most posterior portion, a suture passing through the soft palate is performed. It is anchored to the sphenoid rostrum with two stitches that pass through two holes made in the sphenoid rostrum, above the choane, thus creating a new septum made of two layers of pericranial flap.
- – It would be advisable to place nasal packing during 48-72 hours, as well as silicone nasal splints anchored in the most anterior region of the remains of the nasal septum.