Thirty-Day Complications following Intradural Versus Extradural Excision of the Skull Base

Background: Inherent disparities between surgical approaches for intradural and extradural excisions of skull base lesions may engender varying risks for acute complications. This study aims to elucidate such differences by comparing rates of 30-day morbidity and mortality between intradural and extradural resection of the skull base.

Methods: The 2005 to 2017 American College of Surgeons National Surgical Quality Improvement Program database was queried for surgical cases with primary current procedural terminology codes designating intradural and extradural excision of lesions in anterior, middle, or posterior cranial fossae. All noted complications occurred within 30 days of the operation. Total complications included any surgical or medical complications, readmission, reoperation, and mortality.

Results: A total of 1,168 cases were extracted for analysis, consisting of 701 (60.0%) intradural and 467 (40.0%) extradural resection of skull base lesions. The two cohorts had similar age (p = 0.133), body mass index (p = 0.254), race (p = 0.656), functional status (p = 0.986), and ASA scores (p = 0.911). However, the intradural excision cohort had more females (59 vs. 49%; p = 0.001), more nonelective surgeries (16 vs. 10%; p = 0.013), and fewer surgeries by otolaryngologists (11 vs. 71%; p < 0.001). Compared with extradural excision, intradural excision of anterior cranial fossa lesions had higher rates of medical complications (15 vs. 7%; p = 0.031), readmission (18 vs. 8%; p = 0.040), and longer hospital stay (7.1 ± 9.4 vs. 4.1 ± 6.5 days; p = 0.004). Regarding lesions of the infratemporal fossa, parapharyngeal space, and petrous apex, only medical complication rate was higher in intradural compared with extradural excision (22 vs. 9%, p = 0.012). Intradural excision of lesions in the parasellar region, cavernous sinus, clivus, or midline skull base led to higher rates of reoperation (10 vs. 1.5%; p = 0.029), total complications (29 vs. 15%; p = 0.016), and longer hospital stay (6.1 ± 10.3 vs. 3.7 ± 4.3 days; p = 0.004). Furthermore, length of hospital stay was the only significantly different factor between intradural (7.1 ± 8.2 days) and extradural (5.2 ± 4.9 days) excision of lesions in the posterior cranial fossa, jugular foramen, foramen magnum, or C1–C3 vertebral bodies (p = 0.016). When combining all cases of resecting skull base lesions, there were similar rates of mortality (p = 0.910), surgical complications (p = 0.332), and total complications (p = 0.205). However, compared with extradural excision, intradural excision of skull base lesions had higher rates of medical complications (14 vs. 8%; p = 0.002), readmission (12 vs. 8%; p = 0.032), reoperation (10 vs. 6%; p = 0.033), and higher length of hospital stay (6.9 ± 8.1 vs. 4.5 ± 5.7 days; p < 0.001).

Conclusion: Resection of skull base lesions, especially in the anterior cranial fossa and parasellar or midline skull base region, can carry different risks for postoperative complications depending on extent of dural dissection. Intradural resection of skull base lesions is associated with higher rates of medical complications, readmissions, reoperations, and lengthier hospital stays.