Decreasing Morbidity with Nasal Cerebrospinal Fluid Leak Repair: No Fat or Fascia and No Nasal Packing

Introduction: A myriad of methods have been described to repair low- and high-flow nasal cerebrospinal fluid (CSF) leaks, but significant practice variations remain. While the majority of published repair techniques have led to excellent outcomes regardless of CSF leak type, less consideration has been given to the morbidity of commonly performed CSF leak repair methods, such as fat and fascia harvest and nasal packing. The purpose of the study was to determine whether high success rates could still be achieved for CSF leak repair while avoiding the morbidity of fat or fascia lata harvest and nasal packing.

Methods: This was a prospective case series of 56 patients undergoing CSF leak repair of 58 skull base defects. There were 30 low-flow leaks (<1 cm dural defects or normal intracranial pressure, ICP) and 28 high-flow leaks (>1 cm dural defects or elevated ICP). CSF leaks were due to various etiologies, including iatrogenic during skull base tumor resection (n = 32), meningoencephaloceles (n = 18), iatrogenic from sinus surgery (n = 4), and accidental head trauma (n = 4). Defects were located in the following locations: cribriform plate (n = 21), sella (n = 18), planum sphenoidale and tuberculum sellae (n = 12), other sphenoid sinus walls (n = 5), clivus (n = 1), and posterior table of frontal sinus (n = 1). Two-layered reconstruction was performed in 36 cases, with an epidural inlay layer of either porcine collagen (Biodesign duraplasty graft™) (n = 33) or nasal septal bone (n = 3), and nasal mucosa for the onlay layer. Mucosa was harvested as a free mucosal graft for 90% of low-flow CSF leaks (27/30), and vascularized nasoseptal mucosal flap for 68% of high-flow CSF leaks (19/28). For the other low-flow leaks, nasoseptal flaps were used (3/30), and for the other high-flow CSF leaks, no vascularized flaps were available, so free mucosal grafts were used (9/28). Monolayer onlay reconstructions were performed with nasal mucosa in 22 cases: 11 free mucosal grafts and 1 nasoseptal flap for low-flow leaks; 3 free mucosal grafts and 7 nasoseptal flaps for high-flow leaks. No remote site fat or fascia lata harvest was performed. A dural sealant was always applied to graft or flap edges. No nasal or sinus packing was ever placed. Patients remained bedrest for 24 to 48 hours postoperatively before ambulation. For high-flow CSF leaks, a lumbar drain was used in 21 cases (75%) for 48 hours before clamping and ambulation.

Results: Of the 58 patients, only 1 failed initial CSF leak repair (98.3% success). The patient leaked on postoperative day 2 after a low-flow CSF leak repair during a transsphenoidal resection of a pituitary adenoma, but resolved with lumbar drain diversion alone. Therefore, no patients required revision surgery.

Conclusion: Low- and high-flow CSF leaks were successfully repaired in nearly all cases with porcine collagen or nasal septal bone epidural inlay grafts, and free mucosal graft or nasoseptal flap onlays. Fat or fascia lata grafts and nasal packing were not necessary for achieving excellent CSF leak closure rates, and morbidity was reduced by avoiding their use.

Fig. 1 Repair of a low-flow CSF leak after pituitary adenoma resection with porcine collagen inlay (A) and free septal mucosal onlay in process of being placed (B).

Fig. 2 Two-layer closure for a high-flow CSF leak after a craniopharyngioma resection with porcine collagen epidural inlay (A) and nasoseptal flap onlay (B).