Matthew A. Kirkman, William Muirhead and Nick Sevdalis
Ventriculostomy is a relatively common neurosurgical procedure, often performed in the setting of acute hydrocephalus. Accurate positioning of the catheter is vital to minimize morbidity and mortality, and several anatomical landmarks are currently used. The aim of this study was to prospectively evaluate the relative performance of 3 recognized trajectories for frontal ventriculostomy using imaging-derived metrics: perpendicular to skull (PTS), contralateral medial canthus/external auditory meatus (CMC/EAM), and ipsilateral medial canthus/external auditory meatus (IMC/EAM).
Participants completed 9 simulated ventriculostomy attempts (3 of each trajectory) on a model head with Medtronic StealthStation coregistered imaging. Performance measures were distance of the ventricular catheter tip to the foramen of Monro (FoM) and presence of the catheter tip in a lateral ventricle.
Thirty-one individuals of varying seniority and prior ventriculostomy experience performed a total of 279 simulated freehand frontal ventriculostomies. The PTS and CMC/EAM trajectories were found to be significantly more likely to result in both the catheter tip being closer to the FoM and in a lateral ventricle compared with the IMC/EAM trajectory. These findings were not influenced by the prior ventriculostomy experience of the participant, corroborating the significance of these results.
The PTS and CMC/EAM trajectories were superior to the IMC/EAM trajectories during freehand frontal ventriculostomy in this study, and further data from studies incorporating varying ventricular sizes and bur hole locations are required to facilitate a change in clinical practice. In addition, neuronavigation and other guidance techniques for ventriculostomy are becoming increasingly popular and may be superior to freehand techniques, necessitating further prospective data evaluating their safety, efficacy, and feasibility for routine clinical use.
Matthew A. Kirkman, Maria Ahmed, Angelique F. Albert, Mark H. Wilson, Dipankar Nandi and Nick Sevdalis
There is increasing evidence that simulation provides high-quality, time-effective training in an era of resident duty-hour restrictions. Simulation may also permit trainees to acquire key skills in a safe environment, important in a specialty such as neurosurgery, where technical error can result in devastating consequences. The authors systematically reviewed the application of simulation within neurosurgical training and explored the state of the art in simulation within this specialty. To their knowledge this is the first systematic review published on this topic to date.
The authors searched the Ovid MEDLINE, Embase, and PsycINFO databases and identified 4101 articles; 195 abstracts were screened by 2 authors for inclusion. The authors reviewed data on study population, study design and setting, outcome measures, key findings, and limitations.
Twenty-eight articles formed the basis of this systematic review. Several different simulators are at the neurosurgeon's disposal, including those for ventriculostomy, neuroendoscopic procedures, and spinal surgery, with evidence for improved performance in a range of procedures. Feedback from participants has generally been favorable. However, study quality was found to be poor overall, with many studies hampered by nonrandomized design, presenting normal rather than abnormal anatomy, lack of control groups and long-term follow-up, poor study reporting, lack of evidence of improved simulator performance translating into clinical benefit, and poor reliability and validity evidence. The mean Medical Education Research Study Quality Instrument score of included studies was 9.21 ± 1.95 (± SD) out of a possible score of 18.
The authors demonstrate qualitative and quantitative benefits of a range of neurosurgical simulators but find significant shortfalls in methodology and design. Future studies should seek to improve study design and reporting, and provide long-term follow-up data on simulated and ideally patient outcomes.