Anterior temporal lobectomy compared with laser thermal hippocampectomy for mesial temporal epilepsy: A threshold analysis study

- A quantitative comparison of laser ablation versus temporal lobectomy was performed.
- This decision analysis used preliminary multicenter data of laser thermal ablation.
- The laser ablation is inferior overall if Engel I outcome is achieved in less than 43% of patients.
- The laser ablation is inferior overall if long-term complications occur in more than 40% of patients.
- Modeling with short-term data suggests the laser procedure can have similar utility to temporal lobectomy.

PurposeAnterior Temporal Lobectomy (ATL) is the gold standard surgical treatment for refractory temporal lobe epilepsy (TLE), but it carries the risks associated with invasiveness, including cognitive and visual deficits and potential damage to eloquent structures. Laser thermal hippocampectomy (LTH) is a new procedure that offers a less invasive alternative to the standard open approach. In this decision analysis, we determine the seizure freedom rate at which LTH would be equivalent to ATL.MethodsMEDLINE searches were performed for studies of ATL from 1995 to 2014. Using complication and success rates from the literature, we constructed a decision analysis model for treatment with ATL and LTH. Quality-adjusted life years (QALYs) were derived from examining patient preferences in similar clinical conditions. LTH data were obtained from a preliminary multicenter study report following patients for 6-12 months. A sensitivity analysis in which major parameters were systematically varied within their 95% CIs was used.Results350 studies involving 25,144 cases of ATL were included. Outcomes of LTH were taken from a recently presented multicenter series of 68 cases. Over a 10-year postoperative modeling period, LTH value was 5.9668 QALYs and ATL value was 5.8854. Sensitivity analysis revealed that probabilities of seizure control and late morbidity of LTH are most likely to affect outcomes compared to ATL. We calculated that LTH would need to stop disabling seizures (Engel class I) in at least 43% of cases and have fewer than 40% late mortality/morbidity to result in quality of life at least as good as that after ATL.ConclusionsThis decision analysis based on early follow-up data suggests LTH has similar utility to ATL. These early data support LTH as a potentially comparable less invasive alternative to ATL in refractory TLE. LTH utility may remain comparable to ATL even if long-term seizure control is less than that of ATL. Larger prospective studies with long-term follow up will be needed to validate the true role of LTH in the refractory epilepsy patient population.