Diagnostic Value of non-contrast CT in Cerebrospinal Fluid Leakage after Endoscopic Transnasal Surgery for Sellar and Suprasellar Tumors

Background: To study the relationship between pneumocephalus on non-contrast computed tomography (NCCT) and post-operative cerebrospinal fluid leakage (p-CFL) after endoscopic transsphenoidal sellar and suprasellar tumors surgeries. Methods Patients who underwent endoscopic treatment for sellar or suprasellar tumors from January 2018 to March 2020 were consecutively collected and reviewed. The NCCT pneumocephalus (NP) was measured on the first day after operation and the first day after expansive sponge was extracted, respectively. p-CFL was defined as the glucose rhinorrhea content ≥ 1.7 mmol/L in patients who had persistent nasal discharge of clear water-like fluid exacerbated by bending over or performing a Valsalva maneuver. Results Of 253 patients finally enrolled into this study, 32 patients (12.6%) were identified as p-CFL. Compared with patients who had no p-CFL, patients with p-CFL had a higher occurrence of intraoperative CFL, a longer operation duration time, a higher rate of the presence of pneumocephalus on the first-day NCCT after operation (referred to as the first-day NP), and a higher rate of NP volume change between two times NCCT measurements (referred to as the NP change) (all P  < 0.05). In multivariate regression analysis, the first-day NP was independently associated with the occurrence of p-CFL (OR = 6.176, 95%CI = 2.134–17.871, P  = 0.001). While adding the NP change into the regression model, the first-day NP was no longer independently associated with the occurrence of p-CFL, and the NP change (OR = 21.192, 95%CI = 6.292–71.373, P  < 0.001) was independently associated with p-CFL. The ROCs comparison analysis showed that the NP change had a significantly better predicting value than the first-day NP (AUC: 0.988 vs 0.742, Z = 6.451, P  = 0.001). Conclusions NP is an effective imaging marker for predicting p-CFL after endoscopic sellar and suprasellar tumors operation, especially the NP change shows a better predicting value.