Journal of Headache & Pain Management

Migraine is a syndrome with a wide variety of neurological, neuro ophthalmological and non-neurological manifestations. Diagnosis should be based on a good history, information about the attack profile, accompanying symptoms, identification of triggers and family history or synonyms. It is important to make a differential diagnosis between migraine and tension type headaches because the optimal treatments may differ. Many patients (more than 90% in this region of India) with migraine present to the primary care/general practitioners or Physicians and in its fullfledged form the headache is severe with nausea, vomiting and a heightened sensitivity towards light and sound thus easily fulfilling ICHD-3 beta diagnostic criteria for Migraine without aura. However not all migraine attacks have these characteristics and thus can be confusing with infrequent/frequent episodic tension type headaches. According to ICHD-3 beta [1], the diagnostic difficulty most often encountered among the primary headache disorders is to discriminate between mild to moderate migraine without aura from episodic tension type headaches. There is often overlap of migraine and ETTH diagnostic features especially in Pediatric migraine recommendations [1-4]. Patients meeting one of the sets of criteria for Probable (Missing one of the features required to fulfil all criteria) tension type headaches may also meet the criteria for one of the sub forms of Probable migraine. In such cases, ICHD-3 beta recommends to consider all other available information to decide which of the alternative is the more likely but provides no guidance on this. The biggest challenge in primary care practice is to overcome this difficult clinical scenario and many migraines are diagnosed as Tension headaches or Tension vascular headaches. The following clinical features outside of ICHD-3 beta migraine diagnostic features will be immensely helpful for primary care practitioners and Physicians in such situations:

1) Bilateral throbbing head pain-majority of the adult migraineurs report bilateral or unilateral spreading bilateral headaches (In ICHD-3 Beta, it is unilateral and throbbing) [2-4].

2) Migrating head pain-right to left, front to back or vice versa, migrating down (Entities like Epicrania fugax with dynamic topography is extremely rare).

3) Switching sides or different sides in different attacks.

4) Absolute normality in between episodes-the Sine qua none of a migraine attack in difficult clinical situations (along with activity getting affected during attacks-motionless, sits quiet, lie down or sleep off). This is exactly similar to Episodic syndromes (1.6) that may be associated with migraine.

5) Well known/common/regional migraine triggers precipitating activity affected (sit quiet/lie down/sleep off) attacks. Same triggers may precipitate frequent/infrequent ETTH, but usually not aggravated by routine physical activities and duration can vary from 30 min to seven days [5-9].

6) Family history of similar activity affected headaches (or migraine synonyms) with absolute normality in between episodes

7) Motion sickness with or without headaches (akin to episodic syndromes like cyclical vomiting) [10,11].

8) Symptoms of Episodic syndromes present or past-discomfort, gas formation, pain, nausea, vomiting, bloating occurring infrequently, periodically or chronically with absolute normality in between [10-12].

9) Vestibular migraine symptoms-present or past without past history of migraine headaches.

10) Slow build-up of pain-most of the migraines start as mild pain like tension type and slowly escalate to moderate to severe intensity.

11) Premonitory symptoms (it may be difficult to identify, specifically ask about these symptoms that the patients would not otherwise mention) [1,13].

12) Autonomic symptoms-if activity getting affected it is more in favor of migraine rather than Trigeminal autonomic cephalalgias. (TAC patients like to move around-restless, agitated and pacing the floor as in majority of cluster headaches) [12].

13) Sleep/vomiting aborting attacks.

14) Menstrual related headaches-to be specifically enquired [13,14].

15) Periodic sleep disorders/symptoms in children like sleep talking, walking, terror and bruxism [1].

16) Common migraine triggers precipitating head discomfort (throbbing/paresthesia/strange sensations like burning/tingling/ vibrations etc. These symptoms also to be specifically inquired as most of them consider these sensations as different from headaches).

Only Aura is enough to diagnose migraine and presence of headache is not mandatory. With any kind of typical aura (visual, sensory or speech), even tension type headache or without any headache is diagnostic of migraine. At least one aura symptom is unilateral in Typical aura and aura consisting of fully reversible monocular positive and/or negative visual phenomena in Retinal migraine, is confusing for any clinician. The simplest way to diagnose migraine aura is to look at the way it is getting manifested-slow march (from adjacent to fixation and spread to the periphery on one side) or gradually spreading visual hallucination (photopsias) lasting less than one hour must be the Sina qua none of a typical aura. An AVM, manifesting like a typical aura is extremely rare and if switching sides are present, it is not due to a structural lesion. Other rare differential is occipital seizures which are generally shorter in duration (less than 5 min but usually lasting only few seconds), often consist of coloured circles rather than the achromatic zigzags of migraine and usually accompanied by alteration of awareness and by automatisms such as frequent blinking, gaze deviation or blank stare [15]. Although they are often moving, they do not have the stereotypical progression observed in migraine

A definite diagnosis of migraine requires another additional challenging criterion in ICHD-3 beta. Not attributed to another disorder/Not better accounted for by another ICHD-3 beta diagnosis. A detailed history, complete general, physical and neurological exam are mandatory in all migraineurs. Before finally diagnosing migraine with or without auras, RED FLAGS to be kept in mind and ruled out. In ICHD-3 beta, many ominous causing life and vision threatening brain lesions can mimic migraine with or without auras and can manifest as recurrent head pain attacks similar to episodic primary headaches. They are Un ruptured saccular aneurysms, Subarachnoid haemorrhage, RCVS (Reversible cerebral vasoconstriction syndrome), AVMs (Arterio venous malformations), Genetic vasculopthies like CADASIL (Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), MELAS (Mitochondrial encephalopathy, lactic acidosis and stroke like episodes), Cerebral Venous thrombosis, Internal Carotid dissection, Idiopathic intracranial hypertension, Intermittent angle closure glaucoma etc. These can be extremely difficult to recognize initially in a busy practice by both the General practitioner and Physician alike. Remembering two red flag Mnemonics (SNOOP and I WARN U Please) [16,17] will definitely be useful in a busy clinical practice to rule out life and vision threatening headaches. Always rule out a secondary cause with all possible investigations before finally diagnosing Chronic migraine, Chronic tension type headache or Medication overuse headache. One can miss a PHD (Primary headache disorder) but missing an OHD (Ominous headache disorder) can be really disastrous.

References

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