Acta neurochirurgica
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Acta neurochirurgica · Jun 2011
The impact of provider surgical volumes on survival in children with primary tumors of the central nervous system--a population-based study.
Provider volume is often a central topic in debates about centralization of procedures. In Norway, there is considerable variation in provider volumes of the neurosurgical centers treating children. We sought to explore long-term survival after surgery for central nervous system tumors in children in relation to regional provider volumes. ⋯ In this population-based study of children operated over a period of two decades, we found no evidence of improved long-term survival in the high-provider volume region. Surprisingly, a subgroup analysis indicated that survival in PNET/medulloblastomas was significantly better if living outside the most populated health region with the highest provider volumes. One should, however, be careful of interpreting this directly as a symptom of quality of care, as there may be unseen confounders. Our study demonstrates that provider case volume may serve as an axiom in debates about centralization of cancer surgery while perhaps much more reliable and valid but less quantifiable factors are important for the final results.
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Acta neurochirurgica · Jun 2011
Quantitative parameters of facial motor evoked potential during vestibular schwannoma surgery predict postoperative facial nerve function.
Facial motor evoked potential (FMEP) amplitude ratio reduction at the end of the surgery has been identified as a good predictor for postoperative facial nerve outcome. We sought to investigate variations in FMEP amplitude and waveform morphology during vestibular schwannoma (VS) resection and to correlate these measures with postoperative facial function immediately after surgery and at the last follow-up. ⋯ FMEP amplitude ratio and waveform morphology during VS resection seem to represent independent quantitative parameters that can be used to predict postoperative facial function. Event-to-baseline FMEP monitoring is quite useful to dictate when intraoperative changes in surgical strategy are warranted to reduce the chances of facial nerve injury.