Machine Learning and Neurosurgical Outcome Prediction: A Systematic Review.

OBJECTIVE: Accurate measurement of surgical outcomes is highly desirable to optimize surgical decision-making. An important element of surgical decision making is identification of the patient cohort that will benefit from surgery prior to the intervention. Machine learning (ML) enables computers to learn from previous data to make accurate predictions on new data. In this systematic review, we evaluate the potential of ML for neurosurgical outcome prediction. METHODS: A systematic search in the Pubmed and Embase databases was performed to identify all potential relevant studies up to January 1, 2017. RESULTS: Thirty studies were identified that evaluated ML algorithms used as prediction models for survival, recurrence, symptom improvement, and adverse events in patients undergoing surgery for epilepsy, brain tumor, spinal lesions, neurovascular disease, movement disorders, traumatic brain injury, and hydrocephalus. Depending on the specific prediction task evaluated and the type of input features included, ML models predicted outcomes after neurosurgery with a median accuracy and area under the receiver operating curve (AUC) of 94.5% and 0.83, respectively. Compared to logistic regression, ML models performed significantly better and showed a median absolute improvement in accuracy and AUC of 15% and 0.06, respectively. Some studies also demonstrated a better performance in ML models compared to established prognostic indices and clinical experts. CONCLUSION: In the research setting, ML has been studied extensively demonstrating an excellent performance in outcome prediction for a wide range of neurosurgical conditions. However, future studies should investigate how ML can be implemented as a practical tool supporting neurosurgical care.