Impact of Dual-Layer Duraplasty During Hemicraniectomy on Morbidity and Operative Metrics of Cranioplasty: A Retrospective Case-Control Study Comparing a Single-Layer with a Dual-Layer Technique

Background: Dural substitutes used during hemicraniectomy provide a barrier and dissection plane during subsequent cranioplasty. A recent review by our group showed that use of dural substitutes in hemicraniectomy is associated with reduction in estimated blood loss (EBL) and operative time (OT). In our experience, the use of a dual-layer technique facilitates a dissection plane with minimal adhesions. We hypothesized that use of this dual-layer technique would show decreased OT and EBL in patients undergoing cranioplasty. Methods: We conducted a retrospective case-control study comparing use of single-layer versus dual-layer duraplasty on cranioplasty operative outcomes. Data on dual-layer cases were collected from patients who underwent cranioplasty from 2013 to 2017. These data were matched to controls from 2008 to 2012. Patients were identified by query of a neurosurgical database of all procedures performed at our institution. Patients were included if they had complete surgical records for cranioplasty. Cases and controls were compared with a Student t test, χ² test, or Fisher exact test. Results: A total of 78 controls and 45 cases met inclusion criteria. All baseline characteristics between cohorts were similar except for surgical indication. Mean OT (102.97 minutes vs. 102.18 minutes) and mean EBL were not significantly different (204.66 mL vs. 190 mL) between cohorts. Conclusions: In this study, we did not detect any significant difference between EBL and OT with use of single-layer versus dual-layer duraplasty. Mean EBL was slightly higher in the controls compared with cases but this difference was not statistically or clinically significant. This concept would benefit from a prospective randomized study.