Acellular Dermal Allograft for Sellar Reconstruction after Transsphenoidal Hypophysectomy

Abstract

Obliteration of the sphenoid sinus using fat is often used after transsphenoidal hypophysectomy. The morbidity of this approach includes donor site complications, fat necrosis, and delayed mucocele formation. As obliteration with fat is intended to prevent cerebrospinal fluid (CSF) leakage, an alternative for this technique would be techniques used for CSF rhinorrhea repair. Instead of sinus obliteration, these defects are repaired with fascial autografts, which are unfortunately associated with donor site complications. To avoid sinus obliteration and donor site complications, we have reconstructed the sella with acellular dermal allograft in lieu of sinus obliteration. Transsphenoidal hypophysectomy was performed under combined microscopic and endoscopic visualization. For closure, the sellar anterior wall was reconstructed with acellular dermal allograft, septal cartilage/bone autograft, and fibrin glue. The sinus mucosa was then draped over the reconstruction and held in place with microfibrillar collagen hemostat slurry. The sphenoid sinus was not obliterated. Postoperatively, all patients underwent serial nasal endoscopy. Thirteen patients underwent the procedure as described for removal of pituitary adenoma. Postoperative discomfort and pain were minimal. Intraoperative CSF leaks were identified in five patients; none of these patients experienced a postoperative CSF leak. The microfibrillar collagen hemostat was cleared by sphenoid mucociliary clearance. One patient developed acute sphenoid sinusitis several weeks after surgery; this patient did not develop meningitis. One postoperative CSF leak occurred in an obese patient, in whom an intraoperative CSF leak was not identified; this leak resolved with bedrest and delayed lumbar drainage alone. Sellar reconstruction with acellular dermal allograft may eliminate the need for sphenoid sinus obliteration after transsphenoidal hypophysectomy. Acellular dermal allograft sellar reconstruction ultimately provides for an aerated, functioning sphenoid sinus without increased CSF leak risk or potential donor site morbidity.

Need for intrasellar packing in sellar reconstruction of transsphenoidal surgery: Less is more?

“…1,2 Recently, various sellar reconstruction methods have been described. [3][4][5][6] This study compares sellar reconstruction with and without intrasellar packing following the transsphenoidal procedure. The technique without intrasellar packing has been successfully used in 26 patients.…”

One-Piece Modified Gasket Seal Technique

“…Although autologous fat graft has historically been used for prevention of iatrogenic CSF leak following transsphenoidal surgery, this technique carries with it a particular set of risks, such as donor site morbidities, fat graft necrosis, and sinusitis. 32 Excessive sellar packing with fat can also obscure postoperative imaging 33 and result in postoperative visual deterioration due to chiasmal compression. 34 The drawbacks of the original gasket seal method, including prolonged operative time, and the disadvantage of intracranial fat grafting led to our development of the modified onepiece gasket seal technique.…”

Enhancement of Withstanding Pressure of Fibrin Sealant by Modified Mixing Ratio of Fibrin Sealant Components for Skull Base Reconstruction

“…1,2,5,9) In this study, we mimicked sellar reconstruction in ETSS. Focusing on adhesion of fibrin sealant to the bone tissue of the sphenoid sinus, which exhibits relatively little biological reaction in the early postoperative period, we made an experimental model that likewise has no biological reaction, where the dural defect was covered with a Gore-Tex sheet, and hydroxyapatite was employed as a substitute for bone, to get information on the actual relationship between fibrin and bone.…”

“…Various methods, which use autologous tissues, biological agents, artificial agents, and other materials, are employed to prevent CSF leakage 1,2,5,9) and fibrin sealant is the most commonly used agent. In ETSS, fibrin sealant covers the reconstructed site and adheres to the surrounding tissue, particularly to the bony surface of the sphenoid sinus.…”