Abstracts

Rationale: Traditional outcome measures in epilepsy surgery have predominantly focused on seizure freedom. While this remains a crucial metric, there is an increasing need to explore and understand other aspects of patient well-being that surgery could positively influence. This systematic review aims to examine the diversity and comprehensiveness of outcome measures reported in epilepsy surgery literature to identify any potential gaps and trends.

Methods: A comprehensive search was conducted across PubMed, Embase, and Web of Science databases to identify relevant articles published up to September 2023. The studies were assessed for variables such as types of outcome measures reported, type of surgical procedure, study design/population, geographical location, sample size, and year of publication. Trend analysis was performed to calculate the yearly percentages of papers reporting each outcome measure from 2000 onwards. Comparisons between the United States and other countries as well as pediatric and adult studies were conducted.

Results: A total of 1654 articles, including case series, randomized controlled trials, and observational studies were analyzed. The gross number of reports on various outcomes has increased gradually since 2000, with the exception of seizure freedom that has steeply increased from 34 studies in 2000 to 105 in 2023. The trend analysis of papers written indicated seizure freedom and psychometric measures, where both have been trending downward (~98% to ~94% and ~14% to ~6%, respectively). All other various outcomes have had no significant changes in reporting and remain reported in less than 50% of all studies. Seizure freedom reporting has remained steady all over the world, with over 90% of papers reporting on seizure freedom outcomes. Quality of life reporting has also remained steady over the last two decades, with U.S. and Asian countries reporting the least (both 5% of studies) and Canada and Australia reporting the most (16% and 33% respectively). The percentage of papers reporting on psychometric measures has significantly decreased all over the world, e.g. 6% in the U.S., 8% in Canada, 3% in Europe, 6% in Latin America, and 9% in Asia. Studies on neuropsychological measures have seen the increases of 11% in Canada, Latin America and Australia, compared to 8% decrease in the U.S. and 41% decrease in the Middle East. Adverse outcome reporting has increased by 23% both in the U.S. and Latin America. Other countries have seen a significant decrease, e.g. 13% in Canada, 41% in the Middle East, and 8% in Europe.

Conclusions: While seizure freedom remains the predominant focus in epilepsy surgery literature, there is a slow but discernible shift toward recognizing other critical dimensions like quality of life, psychometric, and neuropsychological outcomes. Despite this, the pace of change is slow, indicating a need for a more comprehensive approach in outcome reporting to capture the multifaceted impact of surgical interventions on patients' lives.

Funding: N/A