低悪性度下垂体神経内分泌腫瘍における低悪性度脳脊髄液漏出に対する術後再建術

Various skull base reconstruction techniques have been proposed for the endoscopic trans-sphenoidal approach (eTSA). These methods often involve multilayer closure using autologous fat grafts and fascia lata, frequently combined with lumbar drainage (LD). This study suggests a modification of graded reconstruction methods for low-grade (Grade 0-2) cerebrospinal fluid (CSF) leaks, particularly Grade 2 leaks, following eTSA for pituitary neuroendocrine tumor (PitNET).

A total of 401 consecutive patients who underwent eTSA for PitNET between 2017 and 2022 at a single institution were retrospectively reviewed, and ultimately 338 patients with intraoperative low-grade CSF leaks were included. Skull base reconstruction was performed according to intraoperative CSF leak grades. Grade 2 leaks were further subcategorized into 2a and 2b based on the size of the diaphragmatic defect. Grades 0, 1, and 2a leaks were reconstructed using fibrin sealant patches, hydrogel sealant, and reinforcement with nasoseptal flap (NSF) where required. Grade 2b cases underwent rigid reconstruction with hydroxyapatite (HXA). Autologous fat grafts, fascia lata, and perioperative LD were not used. Postoperative CSF leaks and other complications were analyzed.

Among the 338 cases, there were 235 Grade 0, 55 Grade 1, 40 Grade 2a and 8 Grade 2b intraoperative CSF leaks. No postoperative CSF leaks occurred. Two cases of postoperative meningitis were observed in Grade 2a, all of whom were treated successfully with antibiotics.

Our graded reconstruction approach is an effective and efficient method to prevent CSF leaks after eTSA in PitNET patients with low-grade intraoperative CSF leaks. Further subdividing Grade 2 leaks based on defect size enables more precise and reliable skull base reconstruction. Moreover, autologous fat grafts, fascia lata, and perioperative LD appear unnecessary in low-grade cases.