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The slope of the learning curve in 600 consecutive endoscopic transsphenoidal pituitary surgeries

Acta Neurochirurgica volume 162, pages 2361–2370 (2020)Cite this article

Abstract

Background

Endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma has become a mainstay of treatment over the last two decades and it is generally accepted that once this learning curve is achieved, a plateau is reached with little incremental improvement.

Objective

The objective of this study was to assess the slope of the learning curve over a long period of time for a variety of outcomes measures.

Methods

We examined outcomes and complications in a consecutive series of 600 EETS for pituitary adenoma grouped into quartiles based on date of surgery.

Results

GTR significantly increased across quartiles from 55 to 79% in the last quartile (p < 0.005). The rate of intraoperative CSF leak significantly decreased from 60% in the first quartile to 33% in the last quartile and the rate of lumbar drain placement from 28% in the first quartile to 6% in the last quartile (p < 0.005). Hormonal remission for secreting adenomas increased from 68% in the first quartile to 90% in the last quartile (p < 0.05). The rate of post-operative CSF leak trended lower (3% in first quartile to 0.7% in last two quartiles). The greatest improvement in outcome occurred between the first and second quartiles (19.9%), but persistent improvement occurred between the second and third (6.7%) and third and fourth quartiles (8.0%).

Conclusion

Although the slope of the learning curve is steeper earlier in a surgeon’s experience, the slope does not plateau and continues to increase even over more than a decade.

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Affiliations

  1. Department of Neurosurgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA

    Iyan Younus, Mina M. Gerges, Rafael Uribe-Cardenas, Peter Morgenstern & Theodore H. Schwartz

  2. Department of Otolaryngology, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA

    Ashutosh Kacker, Abtin Tabaee, Vijay K. Anand & Theodore H. Schwartz

  3. Department of Neuroscience, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, NY, USA

    Theodore H. Schwartz

  4. Departments of Neurosurgery, Otolaryngology and Neuroscience, Weill Cornell Medicine, New York-Presbyterian Hospital, 525 East 68th St. Box #99, New York, NY, USA

    Theodore H. Schwartz

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  1. Iyan Younus
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  2. Mina M. Gerges
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  8. Theodore H. Schwartz
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Correspondence to Theodore H. Schwartz.

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Cite this article

Younus, I., Gerges, M.M., Uribe-Cardenas, R. et al. The slope of the learning curve in 600 consecutive endoscopic transsphenoidal pituitary surgeries. Acta Neurochir 162, 2361–2370 (2020). https://doi.org/10.1007/s00701-020-04471-x

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  • DOI: https://doi.org/10.1007/s00701-020-04471-x

Keywords

  • Endonasal
  • Endoscopic
  • Transsphenoidal
  • Follow-up
  • Outcomes
  • Learning curve
  • Tail end
  • Complication
  • Surgery
  • Gross total resection