Research gives GPs clarity in referring headaches for scans

Many GPs face uncertainties when it comes to patients presenting with headaches and when they should be referred for scans.

That’s the claim by a Griffith University academic and general practitioner, but his research suggests other factors such as psychological states should be considered to reduce over-investigation, costs and time, and help reduce risks of radiation exposure.

Dr ChrisIfediorafrom the School of Medicine said although current guidelines rely on the identification of ‘red flags’ for when GPs should order brain imaging for patients with headaches, he says the practical realities are far from simple.

“Brain imaging is sometimes ordered when there is no clear indication for it, particularly in the absence of obvious red flags,” DrIfediorasaid.

“GPs will ask the patient questions to determine if there are any ‘red flags’, which are designed to let GPs know of problems that could determine if the patient is sent to hospital or sent for scans.

“Themore redflags present, the higher the chance of dangers. But often after the GP questions the patient, those red flags are not there. Then the GP is not sure and there can be fears that something might have been missed. Or maybe the patient is putting pressure on the GP to order a scan.

“So even when the red flags are not there GPs are trained to reassure the patient,but very often GPs give in to their own fears and to pressure from the patient.

“What the study finds is that there’s over investigation of those who are also experiencing psychological issues by ordering asometimes unnecessaryscan.”

The findings were publishedinFamily Practiceand have beensummarisedinAustralian DoctorandAustralia Doctor Group.

DrIfediorasaid a closer look at available information in the literature revealed only a small fraction of scans aid in the management of primary headaches, with fewer than 3% of CTs and MRIsactually revealingmeaningful pathologies.

“What we have highlighted is that there is nothing in the red flag guidelines about psychological issues,” he said.

“By looking at the patient’s current psychological state it means GPs can refer a patient to psychologists or counsellors with more clarity, rather than ordering a scan first.”

Another new finding from this study, which is absent from all existing guidelines, is the potential influence of time on the need to repeat head imaging for primary headaches.

The study observed that repeating head scans for the same headaches (in the absence of red flags) within a period five to seven years of an earlier scan, yielded no additional findings.

“Given that practitioners go ahead to repeat head scans in such re-presentations (even if nothing was found in an earlier scan), the study suggested that clinicians may wish toprioritisereferralsto third-party health providers such as optometrists, physiotherapists and psychologists, ahead of repeating scans in such cases,” DrIfediorasaid.

Headache red flags

The Australasian College of Emergency Medicine guidelines recommend CT brain for the following symptoms:

  • Thunderclap headache
  • New headache in the older population
  • New onset headache with history of cancer or immunodeficiency
  • Headache with mental state changes
  • Headache with focal neurological deficit if not previously documented as amigraine with aura
  • Substance abuse with amphetamine or cocaine
  • Patient is pregnant or post-partum
  • Headache causing wakening from sleep or worsened by Valsalvamanoeuvre
  • Progressively worsening headache
  • Significant trauma
  • History of seizures in non-epileptic
  • Headache different to usual migraine
  • Anti-coagulation

Source: ACEM Guidelines on Diagnostic Imaging 2012.2