title: Cool Mist Irrigation Improves Heat Dissipation during Surgical Bone Drilling.
abstract: Objective High-speed drilling generates heat in small cavities and may pose a risk for neurovascular tissues. We hypothesize that a continuous pressurized cold mist could be an alternative approach for better cooling during drilling of bone to access cranial lesions. This study aims to examine this idea experimentally. Design Ex-vivo drilling tests with controlled speed, feed, and depth were performed on cortical bone samples. Thermocouples were embedded underneath the drilling path to compare the temperature rises under mist cooling (at 3°C, < 300 mL/h) and flood irrigation (at 22°C, > 800 mL/h). Results A significant difference exists between these two systems (p value < 0.05). The measured temperature was ∼ 4°C lower for mist cooling than for flood irrigation, even with less than a third of the flow rate. Conclusion Experimental data indicate the capability of mist cooling to reduce heat generation while simultaneously enabling flow reduction and targeted cooling. An improved field of view in an extremely narrow access corridor may be achieved with this technology.
authors.affiliation: Medical School, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Breana R
authors.initials: BR
authors.lastname: Siljander
authors.affiliation: Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Anthony C
authors.initials: AC
authors.lastname: Wang
authors.affiliation: Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Lihui
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan, United States ; Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Shih
authors.affiliation: Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Sullivan
authors.affiliation: Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan, United States ; Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan, United States.
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Tai
keywords: endonasal drilling; high-speed drilling; irrigation; thermal injury
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