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Three Part Question

In [children and adolescents with known migraine] is [MRI better than CT] at [ruling out secondary aetiology]?

Clinical Scenario

A 11 year old girl presents to the Emergency Department with a 2 hour history of a severe throbbing headache. She is a known migraine sufferer, but her headaches have become more frequent in the last 2 months. After history and clinical examination, a diagnosis of migraine is made with possible secondary aetiology. You feel that neuroimaging is appropriate and wonder whether MRI would be better than CT at detecting any abnormalities.

Search Strategy

Medline 1950-July 2010 using Ovid interface
EMBASE 1980-July 2010 using Ovid interface
Cochrane Database of Systematic Reviews (July 2010)

Medline
[(Exp migraine disorders OR exp Headache OR exp Primary Headache Disorders OR exp Headache Disorders) AND (exp Magnetic Resonance Imaging) AND (exp X-Ray Computed Tomography) AND (LIMIT to English language AND Humans) AND (LMIT to “All Child (0-18 years)”)]
EMBASE
[(Exp migraine aura OR exp migraine without aura OR exp migraine with aura OR exp migraine OR exp headache OR exp primary headache) AND (exp Nuclear Magnetic Resonance Imaging) AND (exp Computerised Tomography) AND (LIMIT to (Human and English Language)) AND (LIMIT to (child OR preschool child <1 to 6 years> OR school child <7 to 12 years> OR adolescent <13 to 17 years>)(LIMIT to 'clinical query' diagnosis(optimized))
Cochrane Database of Systematic Reviews (July 2010)
Search’migraine’ (ti,ab,kw)

Search Outcome

180 papers found in Medline, 1 was relevant
82 papers found in EMBASE, 1 was relevant
98 papers found in Cochrane, none were relevant

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
M. J. Kuhn et al 1990 U.S	74 patients aged 9-39 years; all had <2yr history of classical migraine & no other significant medical history.	Comparative Study; CT vs MRI	Abnormalities found in MRI & CT scans (compared) in migraine sufferers	Both are useful in detecting abnormalities. 36 patients (49%) abnormalities detected by MRI vs 27 patients (36%) detected by CT. MRI is better than CT.	Weakly relevant to clinical question; adults are included in study as well as children, low quality evidence. Methodology unclear, does not specify how patients have been chosen etc.
S. Aysun et al 1998 Turkey	92 patients with headache, migraine was the most frequent cause.	Case series	Efficacy of neuroimaging studies in investigation of headache	% findings relevant to headache; CT 4.2%, MRI 33.3%, Radiography 16%, EEG 25%. MRI has highest yield.	ABSTRACT ONLY.

Comment(s)

Both studies provide relaitvely low quality evidence, but both conclude that MRI is better than CT at detecting abnormalities.

Clinical Bottom Line

MRI should be used instead of CT if neuroimaging is required.

References

1. M. J. Kuhn, P. C. Shekar A Comparative Study of Magnetic Resonance Imaging and Computed Tomography in the Evaluation of Migraine Computerised Medical Imaging and Graphics 1990; 14: 2, 149-152
2. S. Aysun, M. Yetuk Clinical Experience on Headache in Children: Analysis of 92 Cases Journal of Child Neurology 1998;13:202-210