Seizure (Investigation)
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Population Covered By The Guidance
This pathway provides guidance on the imaging of patients presenting with their first episode of seizure. A protocol for imaging patients with recalcitrant seizures is also included.
Date reviewed: August 2014
Date of next review: May 2023
Published: December 2014
Quick User Guide
Move the mouse cursor over the PINK text boxes inside the flow chart to bring up a pop up box with salient points.
Clicking on the PINK text box will bring up the full text.
The relative radiation level (RRL) of each imaging investigation is displayed in the pop up box.
SYMBOL | RRL | EFFECTIVE DOSE RANGE |
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None | 0 |
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Minimal | < 1 millisieverts |
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Low | 1-5 mSv |
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Medium | 5-10 mSv |
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High | >10 mSv |
Images
Teaching Points
Teaching Points
- Patients without a provoked cause of first seizure require further evaluation through imaging
- In the emergency setting, contrast enhanced CT of the brain is a useful initial investigation
- MRI can depict subtle abnormalities that may go unrecognised on CT. Specific seizure protocols may be utilised in order to identify the epileptogenic focus
- Refractory epilepsy requires specialist referral. Video EEG, SPECT and PET have a role in this sub-group of patients
References
References
References are graded from Level I to V according to the Oxford Centre for Evidence-Based Medicine, Levels of Evidence. Download the document
- Connor SEJ, Jarosz JM. Magnetic resonance imaging of patients with epilepsy. Clin Radiol. 2001;56:787-801. (Review article)
- Bradley WG, Shey RB. MR imaging evaluation of seizures. Radiology. 2000;214:651-6. (Review article)
- King MA, Newton MR, Jackson GD, et al. Epileptology of the first-seizure presentation: a clinical, electroencephalographic, and magnetic resonance imaging study of 300 consecutive patients. Lancet. 1998;352:1007-11. (Level II evidence). View the reference
- Scheuer ML, Pedley TA. The evaluation and treatment of seizures. N Engl J Med. 1990;323(21):1468-74. (Review article)
- Spencer SS. The relative contributions of MRI, SPECT, and PET imaging in epilepsy. Epilepsia. 1994;35(S6):S72-S89. (Level III evidence)
- Van Paesschen W, Duncan JS, Stevens JM, et al. Etiology and early prognosis of newly diagnosed partial seizures in adults: a quantitative hippocampal MRI study. Neurology. 1997;49:753-7. (Level III evidence)
- Latack JT, Abou-Khalil BW, Siegel GJ, et al. Patients with partial seizures: evaluation by MR, CT and PET imaging. Radiology. 1986;159:159-63. (Level III evidence)
- Laster DW, Penry JK, Moody DM, et al. Chronic seizure disorders: contribution of MR imaging when CT is normal. Am J Neuroradiol. 1985;6:177-80. (Level II/III evidence)
- Bergen D, Bleck T, Ramsey R, et al. Magnetic resonance imaging as a sensitive and specific predictor of neoplasms removed for intractable epilepsy. Epilepsia. 1989;30:318-21. (Level III evidence)
- Rigamonti D, Hadley MN, Drayer BP, et al. Cerebral cavernous malformations: incidence and familial occurrence. N Engl J Med. 1988;319:343-7. (Level III evidence)
- Ramirez-Lassepas M, Cipolle RJ, Morillo LR, et al. Value of computed tomographic scan in the evaluation of adult patients after their first seizure. Ann Neurol. 1984;15:536-43. (Level III evidence)
- Theodore WH, Dorwart R, Holmes M, et al. Neuroimaging in refractory partial seizures: comparison of PET, CT and MRI. Neurology. 1986;36:750-9. (Level III evidence)
- Sempere AP, Villaverde FJ, Martinez-Menendez B, et al. First seizure in adults: a prospective study from the emergency department. Acta Neurol Scand. 1992;86:134-8. (Level III evidence)
- Schoenenberger RA, Heim SM. Indication for computed tomography of the brain in patients with first uncomplicated generalized seizure. BMJ. 1994;309:986-9. (Level III evidence)
- Commision on Neuroimaging of the International League Against Epilepsy. Guidelines for neuroimaging evaluation of patients with uncontrolled epilepsy considered for surgery. Epilepsia. 1998;39(2):1375-6. (Practice guideline)
- Sperling MR, Wilson G, Engel J Jr, et al. Magnetic resonance imaging in intractable partial epilepsy: correlative studies. Ann Neurol. 1986;20:57-62. (Level II/III evidence) (Guideline document)
- Mullan BP, O'Connor MK, Hung JC. Single photon emission computed tomography. Neuroimaging Clin N Am. 1995;5(4):647-73. (Review article)
- DeCarli C, McIntosh AR, Blaxton TA. Use of positron emission tomography for the evaluation of epilepsy. Neuroimaging Clin N America. 1995;5(4):623-45. (Review article)
- Harden CL, Huff JS, Schwartz TH, Dubinsky RM, Zimmerman RD, Weinstein S, Foltin JC, Theodore WH. Reassessment: Neuroimaging in the emergency patient presenting with seizure (an evidence-based review): Report of the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology. Neurology. 2007;69:1772-80. (Level I evidence)
Information for Consumers
Information for Consumers
Information from this website |
Information from the Royal Australian and New Zealand College of Radiologists’ website |
Consent to Procedure or Treatment Radiation Risks of X-rays and Scans Magnetic Resonance Imaging (MRI) |
Contrast Medium (Gadolinium versus Iodine) Iodine-Containing Contrast Medium Magnetic Resonance Imaging (MRI) Radiation Risk of Medical Imaging During Pregnancy Radiation Risk of Medical Imaging for Adults and Children |
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