Use of Anterior Temporal Lobectomy for Epilepsy in a Community-Based Population

Figure 1. Trend in total temporal lobectomies performed at the Mayo Clinic from 1993 to 2009. From 1993 to 2009, 847 anterior temporal lobectomies were performed for medically intractable epilepsy. This figure demonstrates the trend in cases over this period. The y-axis is the percentage of total cases performed in that year; the black box is the estimated percentage of the total for that year with error bars representing the 95% CI. The line demonstrates the linear regression of this trend, which has a slope significantly less than zero (slope = −0.37, 95% CI, −0.47 to −0.25; P < .001). Overall, there is a reduction in cases over the study period.

Figure 2. Population-based use rates. A, Kaplan-Meier curve representing the total number of cases and loss over time with 95% CI. Note the large reductions in numbers in the first 5 years to 1997, ie, the median time to 50% of cases is 1996 or 4 years into the 17-year study. B, Population-based use rates for anterior temporal lobectomy with 95% CIs for each year of the study. This difference was significant based on Poisson regression (P = .01).

Figure 3. Number of publications per year of anterior temporal lobectomy and epilepsy. From 1980 to 2010, 2099 of 2327 publications pertaining to mesh terms temporal lobe epilepsy and surgery occurred via search of Ovid MEDLINE. This figure demonstrates the trend in publications over this period. There is a significant increase in publications starting after 1988 (P < .001). The line demonstrates the linear regression of this trend, which has a slope significantly greater than zero (mean [SD] slope = 4.082 [0.3196]; r² = 0.849; P < .001). Overall, there is a substantial increase in publications over the study period.

Figure 4. Cumulative incidence of focal epilepsy of unknown cause among Rochester, Minnesota, residents by decade and proportion of incident cases with history of febrile seizures. A, Cumulative incidence of focal epilepsy to age 45 years in Rochester by age during 1955 to 1964, 1965 to 1974, 1975 to 1984, and 1985 to 1995. B, Percentage of cases with focal epilepsy of unknown cause with history of febrile seizures in Rochester among individuals diagnosed with epilepsy in 1955 to 1964 (n = 27), 1965 to 1974 (n = 36), 1975 to 1984 (n = 54), and 1985 to 1994 (n = 41). In the decades from 1955 to 1984, history of febrile seizures represents 15.4% of those diagnosed. However, in the final decade relative to our data, there is a reduction to 4.9% (P = .08 for comparison of 1955-1984 vs 1985-1994).