1. Rational brain imaging in primary care
Richard Sylvester
Consultant Neurologist
Homerton University Hospital / NHNN
Rational brain imaging in primary care

2. Why image the brain?

3. Brain imaging in primary care
Vast majority requests are MRI for headache
Where does MRI fit in the management of headache?
What headaches present?
Managing headache – pearls and pitfalls
Developing an integrated pathway for headache

4. Headache – relieving symptoms is the aim
Correct diagnosis – history/examination Effective management – knowledge Tests valuable only in minority of cases

5. Headaches – neurology OP
Homerton neurology OPD (Oct – Dec 2012)
94/352 (27%) patients main complaint headache
96% primary (78% migraine, 13% TTH, 9% other)
45% analgesia overuse
1/3 previous imaging
1/3 imaged after clinic
85% discharged

6. Headaches – primary care
>90% migraine
>65% analgesia overuse
When GP diagnosis is migraine – correct 98%
If GP diagnosis is not migraine – incorrect 82%
(Tepper et al, Headache 2004)

7. Diagnosing migraine Recurrent attacks
Headache lasting 4–72 hours untreated
At least two symptoms of:
Throbbing/pulsating
Unilateral
Moderate or severe
Worsened by movement/avoids routine physical activity
And either:
Nausea +/or vomiting
Photophobia or phonophobia
ICHD-2, 2004

8. Managing migraine
Lifestyle – regular sleep, food/drink, reduce stress Abortive – high dose NSAID/domperidone - triptan/domperidone Prophylactic – propanalol, AEDs, amitriptylline Education – migraine trust website (Imaging – <1:2200 brain tumour)

9. Improving management Underdiagnosis Undermanaged NMC guidance for GPs
Lack of all migrainous symptoms
Absence of aura (>80%)
Chronic headache – analgesia overuse
Undermanaged
Analgesia overuse propagated
Abortives not used correctly
Prophylactics - dose / length of treatment
NMC guidance for GPs

10. Analgesia overuse headache
>14 days month >2 days analgesic use per week Any analgesic Underlying primary headache Reduces efficacy of prophylactics Addiction pathway?

11. Other headaches
Primary TTH – featureless, no analgesia overuse Cluster – 1-3 hrs, agitated TACS – rare Secondary ‘Red flags’

12. Why order a brain scan in someone with headache?
Diagnose/exclude serious pathology Relieve anxiety (patient / doctor) Avoid referral to specialist (cost) Patient choice

13. What does imaging achieve in headache?
It excludes serious pathology
But headache alone is not a marker of structural pathology
‘red flag’ features are – need specialist input/imaging
Thunderclap headache (peak intensity 1-5mins lasting >1hr)
Fever/systemic illness
Focal neurology / seizures
Cognitive decline
New onset daily headache in high risk group
(>50yrs/cancer/immunosuppressed)
Postural features suggestive low / high CSF pressure

14. What does imaging achieve in headache?
It relieves anxiety
Maybe in the short term but not for long
RCT imaging vs none
Outcome measure – anxiety scores / Is my headache caused by something serious ?
Less anxiety at 3 months but not at one year
(Howard et al JNNP 2005)
Around 5% are not normal – more anxiety
Chiari malformations
Arachnoid/Pineal cysts
Small meningiomas/aneurysms
White matter lesions
Pituatary abnormalities

15. What does imaging achieve in headache?
Avoids specialist referral and reduces costs
No cost benefit – minor reduction in referral rate
(Wills et al, JNNP 2005)
Open Access MRI with GP referral guidelines
169 scans in 12 months
Incidentaloma rate: 3%
No reduction in costs and minor reduction in referrals
Imaging doesn’t diagnose and manage symptoms

16. What does imaging achieve in headache?
Patients want scans
Yes but they would prefer to get rid of their symptoms
Normal scan may lead to trivialising symptoms

17. When do I use imaging?
Red flags Triggered headache Head injury NODPH Rare phenotypes When I have little choice!

18. What imaging do I use? CT
short wait, good for fractures / large lesions / less incidentalomas but radiation, poor resolution
MRI – often need specific sequences
Trauma – GE/SWI
?low CSF pressure – contrast
TACS – pituitary imaging
TN – brainstem sequences
MRA/MRV – arterial/venous pathology

19. NMC guidelines for primary care

20. Neurology advice
Urgent - Neurology SPR Homerton / RLH Routine - advice line

21. Yes
Yes
Red flags?
Urgent?
A&E / medics / neuro SPR No
Neurology OP
advice service No
Imaging
Analgesia overuse?
Stop analgesics
success?
Yes
?psychiatry input No No
Imaging
Yes
Treatment
Triggers
Abortive
Prophylaxis
Neurology OP
advice service
Diagnostic pattern?
Migraine?
Yes
Yes No No No
Yes
Others – cluster, TACS
Triggered, NODPH
Headache diary
Review in 8/52
Diagnosis?
Primary care management
e.g. TTH, musculoskeletal No
Neurology OP
advice service
Imaging

22. Developing an integrated headache pathway

23. Conclusions
Always consider the aims and likely outcomes of brain imaging There are limited indications for brain imaging in headache Correct diagnosis and management are more reassuring than normal tests Its usually migraine and analgesia overuse!

24. Useful information
Migraine trust National migraine centre BASH