Cost-effective utilization of single photon emission computed tomography (SPECT) in decision making for epilepsy surgery

PURPOSE To investigate the utility of single photon emission computed tomography (SPECT) without subtraction and MRI co-registration in decision making for epilepsy surgery. METHODS Patients with refractory epilepsy and nonlocalizing or discordant non-invasive data (clinical, long-term VEEG, and MRI) were subjected to interictal and ictal SPECT studies before planning invasive or surgical strategy. Final localization was based upon the preoperative information and seizure freedom after surgery. SPECT was considered to be useful for decision-making if it obviated the need for intracranial monitoring or influenced its planning. RESULTS 61 patients (mean age, 25.1±8.3 years) underwent SPECT studies between January 2004 and December 2008. Twenty-two patients had mesial temporal lobe epilepsy (MTLE), 13 had neocortical temporal lobe epilepsy (NTLE), and 26 had extratemporal lobe epilepsy (ETLE). As compared to ETLE, SPECT provided more localizing information (77.3% vs 46.2%, p=0.006) and influenced the final decision-making (45.4% vs 11.53%, p=0.005) in a significantly higher number of patients with MTLE. SPECT was particularly useful in patients with lesional TLE and nonlocalizing ictal data and in those with dual pathologies. SPECT did not provide any additional information in patients having either TLE or ETLE with normal MRI. CONCLUSIONS SPECT is useful in a selected group of patients and unlikely to provide additional information in others. By restricting its use in patients who are likely to be benefited, a cost-effective utilization strategy can be employed in countries with limited resources. Due to the small number, these findings need to be validated in a larger group of patients.