The nasoseptal flap, also known as the Hadad-Bassagasteguy flap (HB flap), was developed at the University of Rosario, Argentina, and the University of Pittsburgh and was first described in 2006 1)
The development and widespread utilization of the nasoseptal flap has revolutionized anterior skull base reconstruction. Before the description of the nasoseptal flap in 2006, other local vascularized flaps such as the pericranial or temporoparietal fascia flaps were utilized and conveyed potentially unnecessary morbidity to patients. Reconstruction of the anterior skull base does not always require a vascularized tissue flap and can often be achieved with non-vascularized autologous or synthetic grafts. However, large skull base defects involving high-flow cerebrospinal fluid leaks require vascularized tissue reconstruction to avoid post-operative CSF leak and resultant complications. The nasoseptal flap utilizes mucosa based on a vascular pedicle within the nasal cavity that minimizes morbidity and maximizes success for anterior skull base surgical procedures 2).
The reliable vascular supply promotes rapid healing and the flap is an effective barrier for the prevention of CSF leaks. For large skull base defects, it has dramatically decreased the risk of a postoperative CSF leak to less than 5%. The nasoseptal flap is a versatile flap with a wide arc of rotation that allows the flap to reach defects from the frontal sinus to the lower clivus 3).
The nasoseptal flap is harvested from the nasal septum, which is the wall of tissue that separates the left and right nostrils.
It is a vascularized flap, meaning it contains blood vessels that contribute to its viability.
The nasoseptal flap is versatile and can be used to reconstruct various areas of the anterior skull base, including the sella turcica, planum sphenoidale, and tuberculum sellae.
The flap's vascular supply is derived from the anterior ethmoidal artery, a branch of the ophthalmic artery. The vascularization of the flap enhances its survival and promotes effective healing in the reconstructed area.
The nasoseptal flap is designed to provide coverage and support to the skull base defect created during surgery. It helps prevent complications such as cerebrospinal fluid leaks, which can occur when there are breaches in the dura mater.
The flap is typically elevated and rotated into position to cover the defect. Care is taken to ensure a watertight seal and proper positioning to optimize healing.
The use of the nasoseptal flap is particularly effective in preventing CSF leaks, a common concern in anterior skull base surgery.
It reduces the risk of postoperative infections and other complications related to skull base defects.
The flap is an autograft, meaning it comes from the patient's tissue, reducing the risk of rejection.
Its proximity to the surgical site simplifies the harvesting process.
Close postoperative monitoring is essential to detect any signs of complications, and imaging studies may be performed to assess the success of the reconstruction.
In summary, the nasoseptal flap is a valuable tool in anterior skull base reconstruction. Its vascularized nature, ease of harvest, and versatility make it a preferred choice for surgeons performing endoscopic endonasal skull base surgery, especially when dealing with lesions or tumors in the sella turcica and adjacent areas.
The Hadad-Bassagasteguy vascularized nasoseptal pedicled flap (HBF) is an effective technique for the reconstruction of skull base defects with a low incidence of postoperative cerebrospinal fluid leak. Advanced planning is required as posterior septectomy during transsphenoidal surgery can preclude its use due to the destruction of the vascular pedicle.
Endonasal Approaches (EEAs) have been widely used for various skull base lesions. The reconstruction of the skull base defects is of vital importance to prevent postoperative complications. The vascular pedicled-nasoseptal flap (Hadad-Bassagasteguy flap) is used as a workhorse in reconstruction of majority of the defects.
MRI is a very useful tool in assessing the viability of the flap postoperatively and to evaluate for variations that may suggest potential flap failure 4).