Skip to main navigation menu Skip to main content Skip to site footer

Original article

Vol. 142 No. 2324 (2012)

Secondary MRI-findings, volumetric and spectroscopic measurements in mesial temporal sclerosis

  • Maria Luisa Lopez-Acevedo
  • Manuel Martinez-Lopez
  • Rafael Favila
  • Ernesto Roldan-Valadez
Cite this as:
Swiss Med Wkly. 2012;142:w13549


INTRODUCTION: Primary- and secondary MR findings, volumetric measurements and MR spectroscopy data of each hippocampus represent more a dozen of variables that radiologists should consider in a quantitative MR report of temporal lobe epilepsy (TLE). There is a paucity of data about the significance of secondary MR findings simultaneously evaluated with volumetry and MR spectroscopy. We analyzed the influence of qualitative-secondary MR findings simultaneously with quantitative (volumetry and spectroscopy) data in MRI positive- and negative patients with mesial temporal sclerosis (MTS).

METHODS: Analytic and transversal study of 59 patients with TLE and suspiciousness of MTS. 13 variables were analyzed for each hippocampus: age, gender, cerebral hemisphere, temporal lobe atrophy, choroidal fissure dilatation, mamillary body atrophy, collateral white matter atrophy, fornix asymmetry; Naa/Cr, Cho/Cr, mI/Cr, Naa/(Cr+Cho); and hippocampus volume (mm3). Multivariate discriminant analysis (DA) was performed with the aim to identify specific morphologic and metabolic attributes in hippocampi with and without MTS.

RESULTS: Discriminant function significantly differentiated the hippocampi with- and without MTS (Wilks’ λ = 0.211, χ2 (11) = 116.072, p = < .001. The model explained 79.03% of the variation in the grouping variable. The pooled within-groups correlations showed the highest influence of discriminating function for the secondary MR findings over metabolite indices and hippocampal volumes, the overall predictive accuracy was 93.9%.

DISCUSSION: Due of the large number of variables (qualitative and quantitative) to which a radiologist is exposed in a conventional hippocampal MR-report, such evaluation might benefit from the use of predictive models generated by unconventional statistical methods, such as DA.


  1. Engel J, Jr. Surgery for seizures. N Engl J Med. 1996;334(10):647–52.
  2. Achten E, Boon P, Van De Kerckhove T, Caemaert J, De Reuck J, Kunnen M. Value of single-voxel proton MR spectroscopy in temporal lobe epilepsy. AJNR Am J Neuroradiol. 1997;18(6):1131–9.
  3. Vainio P, Usenius JP, Vapalahti M, Partanen K, Kalviainen R, Rinne J, et al. Reduced N-acetylaspartate concentration in temporal lobe epilepsy by quantitative 1H MRS in vivo. Neuroreport. 1994;5(14):1733–6.
  4. Thompson JE, Castillo M, Kwock L, Walters B, Beach R. Usefulness of proton MR spectroscopy in the evaluation of temporal lobe epilepsy. AJR Am J Roentgenol. 1998;170(3):771–6.
  5. Henry TR, Chupin M, Lehericy S, Strupp JP, Sikora MA, Sha ZY, et al. Hippocampal sclerosis in temporal lobe epilepsy: findings at 7 T(1). Radiology. 2011;261(1):199–209. Epub 2011/07/13.
  6. Doelken MT, Stefan H, Pauli E, Stadlbauer A, Struffert T, Engelhorn T, et al. (1)H-MRS profile in MRI positive- versus MRI negative patients with temporal lobe epilepsy. Seizure. 2008;17(6):490–7. Epub 2008/03/14.
  7. Hammen T, Kerling F, Schwarz M, Stadlbauer A, Ganslandt O, Keck B, et al. Identifying the affected hemisphere by (1)H-MR spectroscopy in patients with temporal lobe epilepsy and no pathological findings in high resolution MRI. Eur J Neurol. 2006;13(5):482–90. Epub 2006/05/26.
  8. Jack CR, Jr., Sharbrough FW, Cascino GD, Hirschorn KA, O’Brien PC, Marsh WR. Magnetic resonance image-based hippocampal volumetry: correlation with outcome after temporal lobectomy. Ann Neurol. 1992;31(2):138–46.
  9. Jack CR, Jr. Epilepsy: surgery and imaging. Radiology. 1993;189(3):635–46.
  10. Bronen RA. Epilepsy: the role of MR imaging. AJR Am J Roentgenol. 1992;159(6):1165–74.
  11. Jackson GD, Berkovic SF, Duncan JS, Connelly A. Optimizing the diagnosis of hippocampal sclerosis using MR imaging. AJNR Am J Neuroradiol. 1993;14(3):753–62.
  12. Berkovic SF, Andermann F, Olivier A, Ethier R, Melanson D, Robitaille Y, et al. Hippocampal sclerosis in temporal lobe epilepsy demonstrated by magnetic resonance imaging. Ann Neurol. 1991;29(2):175–82.
  13. Bronen RA, Fulbright RK, Spencer DD, Spencer SS, Kim JH, Lange RC, et al. Refractory epilepsy: comparison of MR imaging, CT, and histopathologic findings in 117 patients. Radiology. 1996;201(1):97–105.
  14. Baldwin GN, Tsuruda JS, Maravilla KR, Hamill GS, Hayes CE. The fornix in patients with seizures caused by unilateral hippocampal sclerosis: detection of unilateral volume loss on MR images. AJR Am J Roentgenol. 1994;162(5):1185–9.
  15. Kim JH, Tien RD, Felsberg GJ, Osumi AK, Lee N. Clinical significance of asymmetry of the fornix and mamillary body on MR in hippocampal sclerosis. AJNR Am J Neuroradiol. 1995;16(3):509–15.
  16. Mamourian AC, Brown DB. Asymmetric mamillary bodies: MR identification. AJNR Am J Neuroradiol. 1993;14(6):1332–5; discussion 6–42.
  17. Mamourian AC, Rodichok L, Towfighi J. The asymmetric mamillary body: association with medial temporal lobe disease demonstrated with MR. AJNR Am J Neuroradiol. 1995;16(3):517–22.
  18. Bronen RA, Cheung G. MRI of the temporal lobe: normal variations, with special reference toward epilepsy. Magn Reson Imaging. 1991;9(4):501–7.
  19. Bronen RA, Cheung G. MRI of the normal hippocampus. Magn Reson Imaging. 1991;9(4):497–500.
  20. Baxendale S. The role of functional MRI in the presurgical investigation of temporal lobe epilepsy patients: a clinical perspective and review. Journal of clinical and experimental neuropsychology. 2002;24(5):664–76. Epub 2002/08/21.
  21. Powell HW, Koepp MJ, Richardson MP, Symms MR, Thompson PJ, Duncan JS. The application of functional MRI of memory in temporal lobe epilepsy: a clinical review. Epilepsia. 2004;45(7):855–63. Epub 2004/07/03.
  22. Fisher RA. The use of multiple measurements in taxonomic problems. Ann Eugen. 1936;7:179–88.
  23. Field A. Discriminant function variates. In: Field A, editor. Discovering statistics using SPSS. London: SAGE Publications Inc.; 2009. p. 599–624.
  24. Bronen R. MR of mesial temporal sclerosis: how much is enough? AJNR Am J Neuroradiol. 1998;19(1):15–8.
  25. Engel J, Jr. A proposed diagnostic scheme for people with epileptic seizures and with epilepsy: report of the ILAE Task Force on Classification and Terminology. Epilepsia. 2001;42(6):796–803. Epub 2001/06/26.
  26. Jack CR, Jr., Bentley MD, Twomey CK, Zinsmeister AR. MR imaging-based volume measurements of the hippocampal formation and anterior temporal lobe: validation studies. Radiology. 1990;176(1):205–9.
  27. Watson C, Andermann F, Gloor P, Jones-Gotman M, Peters T, Evans A, et al. Anatomic basis of amygdaloid and hippocampal volume measurement by magnetic resonance imaging. Neurology. 1992;42(9):1743–50.
  28. Brandao LA, Domingues RC. Brain metabolites and their significance in spectral analysis. In: Brandao LA, Domingues RC, editors. MR Spectroscopy of the Brain. Philadelphia, PA: Lippincott Williams & Wilkins; 2004. p. 10–1.
  29. Field A. Output from the discriminant analysis. In: Field A, editor. Discovering statistics using SPSS. London: SAGE Publications Ltd; 2009. p. 618–21.
  30. Cohen J. Statistical power analysis for the behavioral sciences. 2nd ed. Hillsdale, NJ: Lawrence Erlbaum Associates; 1988.
  31. Wilkinson L. Statistical methods in psychology journals. Task force on statistical inference. APA Board of Scientific Affairs. American Psychologist. 1999;54(8):594–604.
  32. APA. Publication manual of the American Psychological Association. American Psychological Association. 6 ed2009.
  33. Mamourian AC, Cho CH, Saykin AJ, Poppito NL. Association between size of the lateral ventricle and asymmetry of the fornix in patients with temporal lobe epilepsy. AJNR Am J Neuroradiol. 1998;19(1):9–13.
  34. Lee DH, Gao FQ, Rogers JM, Gulka I, Mackenzie IR, Parrent AG, et al. MR in temporal lobe epilepsy: analysis with pathologic confirmation. AJNR Am J Neuroradiol. 1998;19(1):19–27. Epub 1998/02/12.
  35. Castillo M, Smith JK, Kwock L. Proton MR spectroscopy in patients with acute temporal lobe seizures. AJNR Am J Neuroradiol. 2001;22(1):152–7.
  36. Wu WC, Huang CC, Chung HW, Liou M, Hsueh CJ, Lee CS, et al. Hippocampal alterations in children with temporal lobe epilepsy with or without a history of febrile convulsions: evaluations with MR volumetry and proton MR spectroscopy. AJNR Am J Neuroradiol. 2005;26(5):1270–5.
  37. Pallant J. Multivariate analysis of variance. SPSS SURVIVAL MANUAL. 4th ed. Crows Nest, NSW, Australia.: Allen & Unwin; 2011. p. 283–97.
  38. Achten E. Aspects of proton MR spectroscopy in the seizure patient. Neuroimaging Clin N Am. 1998;8(4):849–62.
  39. Lix LM, Sajobi TT. Discriminant analysis for repeated measures data: a review. Frontiers in psychology. 2010;1:146. Epub 2010/01/01.
  40. Lachenbruch PA, Clarke WR. Discriminant analysis and its applications in epidemiology. Methods of information in medicine. 1980;19(4):220–6. Epub 1980/10/01.
  41. Lopinto-Khoury C, Sperling MR, Skidmore C, Nei M, Evans J, Sharan A, et al. Surgical outcome in PET-positive, MRI-negative patients with temporal lobe epilepsy. Epilepsia. 2012;53(2):342–8. Epub 2011/12/24.
  42. Vale FL, Effio E, Arredondo N, Bozorg A, Wong K, Martinez C, et al. Efficacy of temporal lobe surgery for epilepsy in patients with negative MRI for mesial temporal lobe sclerosis. Journal of clinical neuroscience: official journal of the Neurosurgical Society of Australasia. 2012;19(1):101–6. Epub 2011/12/14.
  43. Kuba R, Tyrlikova I, Chrastina J, Slana B, Pazourkova M, Hemza J, et al. “MRI-negative PET-positive” temporal lobe epilepsy: invasive EEG findings, histopathology, and postoperative outcomes. Epilepsy Behav. 2011;22(3):537–41. Epub 2011/10/04.
  44. Immonen A, Jutila L, Muraja-Murro A, Mervaala E, Aikia M, Lamusuo S, et al. Long-term epilepsy surgery outcomes in patients with MRI-negative temporal lobe epilepsy. Epilepsia. 2010;51(11):2260–9. Epub 2010/12/24.
  45. Brodbeck V, Spinelli L, Lascano AM, Pollo C, Schaller K, Vargas MI, et al. Electrical source imaging for presurgical focus localization in epilepsy patients with normal MRI. Epilepsia. 2010;51(4):583–91. Epub 2010/03/04.
  46. Altman DG, Bland JM. Generalisation and extrapolation. BMJ. 1998;317(7155):409–10. Epub 1998/08/08.
  47. Begg CB. Biases in the assessment of diagnostic tests. Statistics in medicine. 1987;6(4):411–23. Epub 1987/06/01.
  48. Ovretveit J, Leviton L, Parry G. Increasing the generalisability of improvement research with an improvement replication programme. BMJ quality & safety. 2011;20 Suppl 1:i87–91. Epub 2011/04/06.