Early neurocognitive outcomes following SEEG with radiofrequency thermocoagulation

Characterization of early neuropsychological outcomes following SEEG with radiofrequency thermocoagulation (RFTHC) is essential to guide patient expectations around return to work, study, and caregiving. The current study aimed to describe the early neurocognitive sequelae of SEEG.

Consecutive patients undergoing SEEG were prospectively recruited from two tertiary epilepsy centers in Melbourne, Australia. Patients were administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) via telehealth before and 3 weeks after SEEG (M = 19.69 days, SD = 4.41). Given the telehealth platform, the coding subtest was substituted for the Symbol Digit Modalities Test, and a modified score of global cognitive function was calculated. To evaluate group changes, paired sample t-tests were performed. Reliable change indices were computed to explore individual-level changes. Pearson's correlation coefficients evaluated relationships between change in global cognitive function and SEEG admission variables. SEEG patients were invited to complete a semi-structured interview canvassing the recovery following SEEG.

Twenty-eight patients completed the neuropsychological examination (M = 37.89 years, SD = 9.72, range = 17-56 years, 54% female). All patients underwent RFTHC with a mean of 11.43 (SD = 6.87, range = 2-28) coagulation sites. At a whole group level, 3-weeks post SEEG there was no evidence for global nor domain-specific cognitive change. Reliable change indices with 90% confidence revealed only 4% (1/28) declined on at least two measures and 10% (3/28) showed psychometric improvement. Pearson's correlational coefficients showed no evidence for association between change in global cognitive function with SEEG factors including admission length, number of spontaneous or stimulated seizures, number of electrodes, or number of RFTHC sites. Subjective reports of language change tended to be accompanied by a decline on the RBANS language index that did not meet reliable change criteria. Most patients reported returning to work around 4 weeks post SEEG.

By 3 weeks, gross cognitive functioning tends to be in keeping with pre-SEEG performances for most patients. These findings have direct clinical implications for SEEG neuropsychological counseling.

SEEG is increasingly used to guide epilepsy surgery. Despite this, little is known about the cognitive recovery in the weeks following the procedure. We found that for most patients, broad cognitive functioning 3 weeks after SEEG with coagulation was consistent with function before SEEG, with only a small minority showing significant changes. Some people who reported language difficulties also showed a decline on language testing, although this was often small. Of those patients working before SEEG, most returned to work by 4 weeks. These results provide important evidence to guide patient counseling, recovery planning, and management after SEEG.