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Published on: February 29, 2020
Little Insights from Big Data: Cerebrospinal Fluid Leak After Skull Base Surgery and the Limitations of Database
Avital Perry1, Panagiotis Kerezoudis2, Christopher S Graffeo1
1Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota, USA.
Background:
Cerebrospinal fluid (CSF) leak is a frustrating complication of skull base surgery. Published methodologies using national surgical databases to assess CSF leak have not accounted for variability between skull base operations.
Objective:
Our goal was to attempt the development of a novel framework for adapting big data techniques to skull base surgery and assess the reliability of corresponding data manipulations.
Methods:
A retrospective nested case-control analysis was performed using patients from the National Surgical Quality Improvement Program (NSQIP) registry, 2012-2015. Current Procedural Terminology and International Classification of Diseases, Ninth Revision codes identified possible skull base operations, which were systematically grouped by anatomic location. Meningioma, schwannoma, pituitary adenoma, and trigeminal neuralgia (TN) were included.
Results:
Of 2918 patients, 84 (2.9%) were readmitted/reoperated on within 30 days for CSF leak. Operations involving the anterior fossa, both middle/posterior fossas in 1 approach, or the orbitocranial zygomatic approach were significantly associated with CSF leak, as were schwannomas and meningiomas in any location (8.5%, 3.1%, 10.2%, 4.1%, and 3.0%; all P < 0.0001). Multivariate analysis of only middle/posterior fossa lesions identified schwannoma (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.3-5.6; P = 0.008), TN (OR, 5.4; 95% CI, 2-14.7; P = 0.008), chronic obstructive pulmonary disease (OR, 3.9; 95% CI, 1.1-14; P = 0.03), and increased operative time (OR, 4.0; 95% CI, 1.7-9.5; P = 0.009) as significant CSF leak risk factors.
Conclusions:
Based on NSQIP data analyzed using a rational skull base/anatomic framework, risk factors for postoperative CSF leak include chronic obstructive pulmonary disease, operative time, anterior fossa meningioma, and middle/posterior fossa schwannoma or TN. Although databases such as NSQIP can be extensively manipulated to generate surrogate results that may provide limited insight, applications beyond their design should be approached carefully.
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