Don't take the plunge: avoiding adverse events with cranial perforators

Clinical article

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The object of this study was to evaluate the causes of plunging events associated with automatic-releasing cranial perforators at the authors' institution.


The authors analyzed a consecutive series of 1652 cranial procedures involving one type of automaticreleasing cranial perforator over a 2-year period. Plunging occurrences were recorded for 2 drill speeds: 1000 rpm in the 1st year and 800 rpm during the 2nd year. Intraoperative observations, neuroimaging studies, and clinical data were evaluated for each plunging event.


The authors identified 9 plunging events for an overall incidence of 0.54%. In the 1st year, they identified 2 plunging events at a speed of 1000 rpm for an incidence of 0.19%. In an effort to reduce this occurrence, the speed of the drill was lowered to 800 rpm. There were 7 additional events, for a significantly increased incidence of 1.16% (p = 0.014, Fisher exact test) after the change was implemented. These cases spanned a number of procedures in adults and pediatric patients, including ventriculostomy placement, craniotomies for tumor resection, tumor biopsy, and endoscopic third ventriculostomy. Despite plunging, no immediate postoperative complications were noted on clinical examination.


While technology continues to improve cranial perforator performance, the use of such a device is still associated with a risk of complications causing dural lacerations and injury to the underlying cortex. Decreasing the drill speed may not decrease the incidence of plunging.

Article Information

Contributor Notes

Address correspondence to: Timothy W. Vogel, M.D., Department of Neurosurgery, UIHC 200 Hawkins Drive, Iowa City, Iowa, 52242. email: include this information when citing this paper: published online April 1, 2011; DOI: 10.3171/2011.3.JNS101310.
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