MR Imaging and Epilepsy—3T or not 3T? that is the Question
Authors: Schwartz Theodore H. 
Published: May 2006

3T-Phased Array MRI Improves the Presurgical Evaluation in Focal Epilepsies: A Prospective Study

Knake S, Triantafyllou C, Wald LL, Wiggins G, Kirk GP, Larsson PG, Stufflebeam SM, Foley MT, Shiraishi H, Dale AM, Halgren E, Grant PE

Neurology 2005;65(7):1026–1031

Background

Although detection of concordant lesions on MRI significantly improves postsurgical outcomes in focal epilepsy (FE), many conventional MR studies remain negative. The authors evaluated the role of phased array surface coil studies performed at 3 Tesla (3T PA-MRI).

Methods

Forty patients with medically intractable focal epilepsies were prospectively imaged with 3T PA-MRI, including high matrix TSE T2, fluid attenuated inversion recovery, and magnetization prepared rapid gradient echo. All patients were considered candidates for epilepsy surgery. 3T PA-MRIs were reviewed by a neuroradiologist experienced in epilepsy imaging with access to clinical information. Findings were compared to reports of prior standard 1.5T MRI epilepsy studies performed at tertiary care centers.

Results

Experienced, unblinded review of 3T PA-MRI studies yielded additional diagnostic information in 48% (19/40) compared to routine clinical reads at 1.5T. In 37.5% (15/40), this additional information motivated a change in clinical management. In the subgroup of patients with prior 1.5T MRIs interpreted as normal, 3T PA-MRI resulted in the detection of a new lesion in 65% (15/23). In the subgroup of 15 patients with known lesions, 3T PA-MRI better defined the lesion in 33% (5/15).

Conclusion

Phased array surface coil studies performed at 3 Tesla read by an experienced unblinded neuroradiologist can improve the presurgical evaluation of patients with focal epilepsy when compared to routine clinical 1.5T studies read at tertiary care centers. MR Imaging of Patients with Localization-Related Seizures: Initial Experience at 3.0T and Relevance to the NICE Guidelines Griffiths PD, Coley SC, Connolly DJ, Hodgson T, Romanowski CA, Widjaja E, Darwent G, Wilkinson ID Clin Radiol 2005;60(10):1090–1099 The purpose of this study is to describe our initial experience of imaging adults with localization-related epilepsy using MR imaging at 3.0T. We discuss the findings in the context of the recently released NICE guidelines that provide detailed advice on imaging people with epilepsy in the UK. One hundred twenty consecutive people over the age of 16 years with localization-related epilepsy were referred for clinical MR examinations from a regional neuroscience center in England. None of the people had had MR examinations prior to the present study. Highresolution MR imaging was performed taking advantage of the high field strength and high performance gradients of the system. Two experienced neuroradiologists reported on the examinations independently and the presence and type of pathology was recorded. There was complete agreement between the two reporters in all 120 cases. The overall frequency of abnormalities shown by MR was 31 of 120 (26%) and the commonest abnormality shown was mesial temporal sclerosis found in 10 of 120 (8%). Tumors were shown in 4 of 120, all of which appeared low grade as judged by imaging criteria. Epilepsy is the commonest neurological condition and demands a significant resource in order to provide good care for sufferers. Recent guidelines published in the UK have suggested that the majority of people with epilepsy should receive brain MR as part of their routine assessment. Our work shows that using the most sophisticated MR imaging in a highly selected population there is a modest pick-up rate of brain abnormalities. If a widespread epilepsy-imaging programme is started the detection rate is likely to be much lower. Although MR is acknowledged to be a reliable way of detecting pathology in people with epilepsy there is a dearth of information studying the health economics of imaging epilepsy in relation to patient management and outcomes.