Answer:

Anterior temporal lobectomy (ATL) is an effective treatment in patients with drug-resistant temporal lobe epilepsy. The Wada test was originally developed to assess the risk of language decline prior to craniotomy and was later applied to predict global amnesia following ATL. Up to ½ of patients undergoing left ATL for drug-resistant focal seizures show a post-operative decline in language or verbal memory function. Language lateralization appears to be a better predictor of verbal memory outcome than Wada memory testing (1). fMRI is non-invasive and may often substitute for the Wada test when lateralizing language. Some authors question the reliability and validity of the Wada test to predict memory outcome. Hence, over time the Wada test has become less often utilized to complement non-invasive studies. In one study only 12% of center used Wada in every TLE candidate (2), and it may be best used in those with atypical language or with significant bitemporal dysfunction. Recent fMRI studies demonstrate the pre-operative predictive value of fMRI for post-operative memory changes (1). Our patient received a right ATL after invasive EEG without language or memory deficits.

References

1. Binder JR. Functional MRI is a valid noninvasive alternative to Wada testing. Epilepsy & Behavior 2011;20:214-220.
2. Baxendale S. The role of the Wada test in the surgical treatment of temporal lobe epilepsy: An international study. Epilepsia 2008;49(4):715-720.

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