CHAPTERS
- History and Examination in HeadacheK Ravishankar, R Allan Purdy
- The International Classification of Headache Disorders (ICHD-3 Beta Version)Tzu-Chou Huang, Shuu-Jiun Wang
- Diagnostic Testing in HeadacheK Ravishankar
- Pathophysiology of Primary HeadachesAndrew C Charles
- Role of Genetics in HeadacheTobias Freilinger
Q. What are the objectives of this chapter?
A. Headache is one of the most common of medical complaints and both acute and chronic headache can be the presenting feature for numerous underlying conditions across all age groups and across different specialties. Since treatment is based on correct diagnosis, it is imperative that we establish a working diagnosis in all headache patients. The aim of this chapter will be to detail the basics of eliciting a comprehensive history in patients who present with headache and to discuss some important aspects of clinical examination. Details of individual diagnostic entities, investigative modalities, and treatment options are discussed elsewhere.
Q. What should be the ideal approach to the headache patient?
A. The ideal approach would be to divide all headaches into two groups—primary and secondary, as outlined in the International Classification of Headache Disorders-3 beta version (ICHD-3 beta version).1 Primary headaches are those where there is no cause identifiable on examination or investigation and where diagnosis is made by pattern recognition based on presenting features, e.g., migraine, cluster headache, and tension-type headache. Secondary headaches have an underlying cause identifiable on examination or investigation, as with subarachnoid hemorrhage, brain tumors, meningitis, etc. More than 90% of headaches seen in practice belong to the primary group and less than 10% to the secondary group.2
The main challenge in practice is to differentiate the benign primary from serious secondary headaches. This can sometimes be complicated since secondary headaches can mimic a primary headache in presentation or may even coexist along with a primary headache. The differentiation between primary and secondary headaches is best achieved through (i) a history that helps detect red flags, danger signals, or atypical features, (ii) a relevant general and neurological examination, and (iii) appropriate investigations that will help confirm the diagnosis.
Q. Why is history so important in headache patients?
A. In classical neurology, history helps create an initial differential diagnostic list, before proceeding to the examination or undertaking investigations. The purpose of the 4history in neurology is to localize the lesion(s) within the nervous system as well as to provide a temporal or time based assessment of the characteristics of the disease. Even with headache, it is vital to try to localize the lesion(s); however, there is now greater dependence on tests, imaging in particular, to make a diagnosis. This is unfortunate, because in headache practice, one arrives at a specific diagnosis not just through examination findings and investigation abnormalities. The history more likely tells us what it is, while investigations more likely tell us what it is not!
Since primary headaches need to be treated differently and specifically, it is necessary to try and arrive at a correct diagnosis. For example, paroxysmal hemicrania (PH), is exquisitely responsive to indomethacin. In practice, however, most clinicians only broadly differentiate between primary and secondary headaches and do not get into specific details of primary headaches. A good history also helps in establishing a rapport between patient and physician because the treatment of headache is often more than just making the right diagnosis and choosing the right medication.
History is important even for the diagnosis of secondary headaches. A proper history helps determine the presence of red flags that direct work-up to rule out ominous underlying causes. The history also serves to avoid misdiagnosis when there are coexisting headache types. History directs the sequence in which investigations should be ordered in patients in whom a secondary headache is suspected.
Q. What are the basic tenets of a good headache history?
A. Headache history-taking is an art that is perfected by practice. Often headache patients are also disheartened because many earlier treatments have failed. It is therefore necessary to also establish a rapport, while asking the right questions based on diagnostic suspicions. Pattern recognition is the cornerstone of headache diagnosis. At the end of the history, based on the setting, the temporal profile and the accompaniments, a provisional working diagnosis must be in place before proceeding to the examination or before planning investigations. It is important to spend more time taking the history than in examining the patient. The art of history-taking improves with practice and the more the patients seen, the better will be the diagnostic expertise.
Primary headaches should be viewed as variations around a theme and a detailed history will help identify the different diagnostic entities. The history helps when the patient has more than one headache type or when there is an atypical presentation of a common primary headache or when a secondary headache mimics a primary headache or when there are comorbidities. A history based on sound knowledge of (i) pain-sensitive structures in the head, (ii) convergence and referral patterns of nerve supply, and (iii) awareness of etiological possibilities and their diagnostic criteria, will help optimize outcome and improve the yield.
Time is an essential prerequisite for taking a good history, because of the need to understand the patient's symptoms and be empathetic. Headache patients have often been through many hasty and disappointing consultations, and have not been told why their head pains. Sometimes great patience is necessary to take the headache history, in order to avoid misdiagnosis, particularly when there is an overlap, as happens with migraine, cluster, sinus-related and tension-type headache. It has been rightly said that “patients respond to physicians who respond”.3
“What the mind does not know, the eyes are not going to see!”4 You need to know what to look for on examination and what test to order in each patient. Knowledge of the neurological and non-neurological conditions, systemic causes and conditions 5from overlap specialties that can present with headache, is a must when regularly seeing headache patients. It helps in practice if one is also familiar with the ICHD-3 beta classification. This classification includes operational diagnostic criteria for each headache entity.1
Q. Who should ideally take the headache history?
A. In patients with headache, the first history is usually the best history. To increase the diagnostic yield and outcome, it is desirable not to delegate the job of history-taking. This might seem obvious but needs emphasis in this modern age. There is no substitute for this and history taking cannot be delegated or gleaned from a calendar or a form filled in by the patient or through a set of yes/no questions on a computer screen. These other ways of getting the history can of course be helpful but a face-to-face encounter with the patient can have significant therapeutic benefits. Thus, one of the first principles is to always take your own history and if it comes from another source, then repeat it yourself at some point in the future.
You can ask the questions in a set sequence and jot down the patient's answers. Through questions, you are looking for clues, some straightforward, some subtle. Another way of eliciting a headache history is to ask the patient, “Can you tell me all about your headaches?” and then ask relevant questions that will cover areas that have been missed out. The specific questions that you will ask will depend on your diagnostic suspicions. It is generally thought that children are not good historians, but all children above the age of 5 years, can give their own history if asked the right questions in simple language.
Accompanying persons can often give useful information about other medical illnesses, depression, drug allergies, medications taken earlier, investigations done, treatments that have failed, alternative treatments tried, extent of disability, the interictal state, and impact of the headache on the patient's lifestyle.
Q. What is a standard history that you will elicit in all headache patients?
A. A routine headache history should begin with a standard set of questions that will elicit basic information. Depending on the acuity of onset, age of the patient, and whether he/she presents to you in the office/consulting room or emergency department/casualty, you will need to elicit additional information to confirm/rule out setting-related entities. In every headache patient, the clinician's worry and the patients fear is that no serious life-threatening cause should be overlooked. It is therefore important to keep in mind the ‘red flags’ or ‘danger signals’ and ask the right questions, in order to be able to decide whether the patient has a serious secondary headache warranting further investigation. Any new onset headache or clinical presentation that is atypical for a primary headache should make one concerned about a secondary headache. The red flags that should caution you to investigate further have been listed in box 1.
The standard set of questions helps direct thought-flow keeping in mind different diagnostic possibilities. Ask about the onset, duration of the headache, period of recent worsening if any, location of the pain, radiation, type of pain, severity, frequency of attacks or episodes, timing, periodicity, and diurnal variation. Check for prodromal features, postdromal features and accompaniments such as nausea, vomiting, photophobia and/or phonophobia, osmophobia. Autonomic features such as lacrimation, nasal stuffiness, redness of eyes, forehead sweating, ptosis, will help as pointers for different diagnostic entities. Ask about triggering factors such as environmental, dietary, or hormonal and precipitating factors such as coughing, 6sneezing, exertion, sexual activity, postural changes, or Valsalva maneuver as well as for factors that may relieve the pain. Ask for the presence of auras—visual, sensory, aphasic, or motor. “How many different types of headache do you have?” is a useful question to detect changes in pattern with long-standing primary headaches or when two headache conditions coexist. When there is more than one type of headache, it is essential to take a separate history for each type of headache.
It helps sometimes to ask the patient to describe step-by-step the sequence of events during an attack or episode. This is usually not taught, but is very important. Patients and diagnosticians are prone to meet each-others’ expectations, so make sure you backup the history by doing parts of it again or by looking at old records or prior opinions and importantly any data collected by the patient in diaries. Do not depend totally on recall, as that can be biased. To use pattern recognition alone is sometimes tricky, if one prematurely thinks it is just another case of migraine, e.g., people without experience always look for a quick diagnosis. In headache, one has to have patience with the patient and go with the flow.
Assess disability levels using instruments such as the migraine disability assessment test (MIDAS), headache impact test (HIT6). Ask for a family history of headache, about occupation, sleep history, personal history, and possible comorbidities, including psychiatric. Ask about systemic illnesses that may be causing the headache and conditions that may be contraindications for the use of prophylactic agents. In all patients with daily headache, medication overuse needs to be ruled out as a contributory factor for chronic headache. End the session with some general questions to ensure that nothing is missed out “Is there anything that you wish to tell me which you think I have not asked you?”, “Why the consultation now?” and “What is your expectation from this consultation?” Answers to these questions can sometimes be quite revealing.3
Q. How do you interpret the information obtained through a standard set of questions?
A.
- Age of the patient, type of onset, and duration of the headache: Age is important since the likelihood of secondary headaches is greater in older patients. Migraine in children presents with features that are different from adults with migraine. New onset headaches should always be taken seriously. If there is an acute onset, severe, first and worst headache, some important possibilities are subarachnoid hemorrhage, reversible cerebral vasoconstriction syndrome, acute hypertensive crisis, vascular dissection, or cerebral venous thrombosis. Rarely pituitary apoplexy, 7colloid cyst, sphenoid sinusitis, or spontaneous intracranial hypotension may also present with acute onset headache. Knowing that this is a new onset headache or something that has worsened recently is important. The longer the time for which the headache has been present, the greater the likelihood of a primary headache
- Location and radiation of the pain: Head pain can be unilateral to begin with and can then become generalized, as with migraine, or it could be holocranial, generalized as with tension-type headache; or it could start periorbitally and then radiate as with cluster headache. Migraine headaches are usually in the temporal region, over the vertex, in the occipital region and often radiate to the neck on the same side as the pain. They often alternate sides but can less commonly remain side-locked. When the headache is side-locked, they warrant investigation to rule out an underlying structural cause. Cluster headache on the other hand is usually side-locked and is mostly periorbital to start with and may spread to becoming hemicranial. Because of an overlapping nerve supply, periorbital headaches can have many causes. Patients with headache who also complain of pain originating in the neck should be investigated to rule out cervicogenic headache, although 75% of migraine patients can have associated neck pain.5 Due to overlapping neural inputs, referral, and convergence patterns, head pain can be perceived in distant locations. Supratentorial structures are innervated by the ophthalmic division of the fifth cranial nerve and posterior fossa structures are supplied by C2 and C3. Therefore, pain from the upper cervical spine or posterior fossa can be referred anteriorly to the front of the head. Facial pain has many causes, of which trigeminal neuralgia is the most common. When a patient presents with facial pain, consider the neuralgias, facial pain syndromes involving the cranial nerves, the trigeminal autonomic cephalalgias (TACs), rhinologic conditions, dental disorders, temporomandibular problems, and idiopathic facial pain. It is also very important to ask for cutaneous triggers for the facial pain as happens with trigeminal neuralgia
- Frequency, attack duration, severity, type of pain: Headaches can have different chronological patterns. Asking about frequency helps ascertain whether it is a monthly, weekly, or daily headache. When it is a daily or near daily headache, ask if it is only once a day or more than once per day? Ask if frequency has increased, if the pain comes at any particular time of the day, if there is a diurnal variation, if it is nocturnal, if it wakes the patient from sleep or whether it is present on awakening. Headaches more likely to present at night are hypnic headache, cluster headache. Headache upon awakening in the morning should suggest the possibility of obstructive sleep apnea, poorly controlled hypertension, raised intracranial pressure, or migraine. Migraine is common on awakening and often worsens later in the day. Ask for any fixed seasonal pattern, with periods of spontaneous remission as with cluster headache, or whether there is a cyclic pattern as with cyclic migraine. If there is a fixed-time relationship, one must keep in mind the possibility of cluster headache
- Change in pattern over time: A progressively worsening frequency unresponsive to treatment indicates the possibility of a secondary cause. Change in pattern in patients with a long-standing history of a primary headache usually warrants investigation. Ascertain if attacks are short- or long-lasting. An arbitrary duration of 4 hours is considered as the cut-off between short- and long-lasting headaches. The TACs such as cluster headache and chronic PH are examples of short-lasting headaches. Primary stabbing headaches are very brief and can last from 10 seconds to 1 minute. Trigeminal neuralgia attacks are lightening stabs of pain that are also of very brief duration, usually a few seconds, as are headaches of short-lasting, 8unilateral, neuralgiform headache with conjunctival tearing (SUNCT) syndrome. Migraine headaches are of longer duration and last anywhere from 4 to 72 hours. Migraine headaches are of shorter duration in children
- Severity of the pain: This can be subjectively gauged either through a verbal rating scale that scores from 0 to 10, where 0 refers to no pain and 10 is the worst pain or through a visual rating scale. Cluster headache and moderate to severe migraine are usually described as a 9/10 or 10/10 severity pain, compared with tension-type headache, which is usually a 3–5/10 severity pain. Note that headache severity does not help differentiate between a primary or secondary headache. The pain of migraine or cluster headache can be just as severe and disabling as that of subarachnoid hemorrhage
- Type of pain: Most headaches that are pulsatile, throbbing, or hammering in nature are usually due to migraine. Tension-type headache is a dull, featureless, and with no accompaniments. Other strikingly different short-lasting pains are the ice pick variety, now called stabbing headache under ICHD-3 beta. Ask if the headache builds-up gradually, as with migraine or whether it peaks rapidly as with the TACs. Two types of headache can coexist and need to be evaluated and treated separately. Confirm that these are distinctive types of headache and not headaches of different levels of severity. Migraine and cluster headache can coexist; cluster headache can be associated with trigeminal neuralgia or migraine patients may have acute sinusitis. When there is more than one type of headache, it helps to obtain details of each type of headache
- Accompaniments of the head pain: Vomiting can be a feature of migraine or of raised intracranial pressure. Hypersensitivity phenomena such as photophobia, phonophobia, or osmophobia are seen more with migraine. Autonomic features such as lacrimation or rhinorrhea are usually seen with the TACs. Ptosis, small pupils (Horner's syndrome), redness of eyes, watering of the eyes, stuffiness of nose, excessive sweating, and pallor, are indirect pointers to TACs. Sometimes, these findings may also be seen with migraine. It is easier to diagnose cluster headache because of the periodicity and distinctive features, but it can be difficult to diagnose the variants. Pulsating, throbbing temporal vessels are seen with migraine whereas a tender painful superficial temporal artery in an elderly patient should suggest giant cell arteritis. Syncope in a headache patient can be seen with migraine or more rarely with a colloid cyst of the third ventricle. When a normally nonpainful stimulus induces pain on touch, this is termed cutaneous allodynia and is seen in many migraine patients and some cluster headache patients. Some manifestations of cutaneous allodynia are listed in box 2
- Triggering factors, precipitating factors, aggravating, and relieving factors: It is important to always inquire about trigger factors—environmental, lifestyle, dietary, and hormonal. Migraine can be triggered by many factors that vary across regions 9and cultures. Ask if there is any link with the menstrual cycle which would suggest the possibility of menstrual migraine. Many headaches can be precipitated by the Valsalva maneuver or with coughing, sneezing, laughing, exertion, or during sexual activity. If there is any increase or reduction with lying down, or postural worsening on standing, suspect an alteration in cerebrospinal fluid (CSF) dynamics, e.g., spontaneous intracranial hypotension. Relieving factors are also important
- Investigations thus far and treatment in the past: While eliciting the history, one has to also plan for investigations based on the diagnostic possibilities (discussed elsewhere). Ask about previous treatments, failed treatments, about excess consumption of abortive drugs like ergots, triptans, and caffeine or codeine containing compounds, which may lead to chronicity and worsening of the headache because of medication overuse.
Q. What other history would you seek in headache patients?
A. Personal history would include a history of smoking, alcohol or medication/drug intake, and allergies. Ask about history of any occupation that could aggravate headaches. Past medical history, and a general inquiry of heart, lung, bowel, and kidney functions are important. Ascertain if the patient has a history of hypertension, asthma, heart disease, abdominal disease, glaucoma, or kidney stones. Ask about medical illnesses that are relevant in a patient presenting with headache, e.g., polycystic ovarian syndrome, hypothyroidism, hyperprolactinemia, drug allergies, and other medications that could induce headache. Some prophylactics may be contraindicated with other medical conditions, e.g., β-blockers in asthma. Recurrent abdominal pain or travel sickness in childhood are pointers to later onset migraine. Ask about head trauma, concussion, or neck injuries and about the presence of general systemic symptoms such as fatigue and weight loss.
Ask about fever and weight loss, which might indicate a systemic infection or malignancy. A history of galactorrhea warrants ruling out of hyperprolactinemia secondary to a pituitary adenoma. Malaria, dengue, or viral fever can sometimes be followed by intense headache. It is essential to rule out immunocompromised states that can lead to opportunistic infections. Neurosarcoidosis or Lyme disease can also present with headache.
Q. How important is family history?
A. A family history of recurrent headaches makes it more likely that you are dealing with migraine. Most migraine patients have a positive family history for headache, maybe up to 75%. Inheritance is probably polygenic in most cases; however in some like familial hemiplegic migraine, the links are more direct and may involve one gene. Get the broad history from the patient about their mother and father and other family members including their children.
Q. What do you need to ask about neurological function in headache patients?
A. This is necessary to ensure that you are not missing something in the history. Ask generic questions to cover all levels of the nervous system such as vision, hearing, smell, and swallowing, arm or leg weakness or numbness as well as positive symptoms like paresthesia. Ask about balance, speech, walking, and bowel and bladder functions. Ask if there is any impairment of consciousness or complex neurological symptoms that can occur with migraine involving the various brain regions. Speech problems such as dysarthria, expressive aphasia, and speech arrest can occur in migraine.10
Visual auras are most common. Spend a lot of time on the visual system when taking the history. The visual history is most important to sort out between migraine with and without aura or for differentiating migraine aura from other migraine mimics and secondary disorders. Patients with migraine with aura have fairly stereotyped visual auras consisting of slow moving scintillations usually of zig-zag nature accompanied in some cases by enlarging negative scotomata. This lasts about 20 minutes and precedes the headache and is usually hemianopic in nature. Any monocular visual loss should not be taken to be migrainous in nature; ophthalmological diseases and cerebrovascular diseases with transient ischemia can present in this manner. Diplopia is rare in primary headaches, as is ptosis or pupillary abnormalities; however they can occur in ophthalmoplegic migraine and cluster headache. Any eye symptom that is atypical in anyway is a red flag and you need to think about secondary causes of headache.
Auras can occur in succession, and the same patient may have a visual aura, followed sequentially by sensory paresthesia or speech difficulty. Conditions that can mimic a migraine aura include strokes, transient ischemic attacks (TIAs), seizure disorders, tumors, venous thrombosis, arteriovenous malformations, and carotid dissections. The onset, progression, and duration of the symptoms help to differentiate between a migraine aura, a TIA, and a seizure. Difficulty in making a distinction between these entities occurs when the aura is not followed by a headache. Gradual onset and progression over a few minutes is characteristic of a migraine aura as compared with a sudden onset in a TIA or a seizure. The classical duration of a migraine aura is 20–30 minutes as compared with a significantly shorter duration for a seizure.
Q. What are the settings in which you will need additional history?
A. Headache history should not follow the same set pattern in all patients. Beyond the standard history, you have to sometimes adapt and modify based on the setting and the suspected diagnosis. If the patient presents to the emergency department with a sudden onset headache, you may need to take a quick history and rapidly order appropriate tests. You may sometimes need to start treatment even before you diagnose. In the emergency room, a patient with a sudden severe headache has probably had a subarachnoid hemorrhage until proven otherwise. In the office or clinic, the same patient might be easily misdiagnosed as having a primary headache disorder. One should avoid telephone or hallway consultations. Nothing replaces an adequate history and proper neurological examination. Never anchor your diagnosis on one aspect of the history but also do not avoid peculiar symptoms. History taking in an emergency department is therefore different from history taking in an office setting; history in a child with headache will differ from history in the elderly patient beyond 50 years who presents with headache, where different conditions need to be suspected (Box 3). The setting is therefore very important in diagnostic considerations for headache (Box 4).
In all headache patients, be on the lookout for and rule out underlying systemic disorders (Box 5). A history of malignancy will raise the possibility of metastases; a history of vascular headaches in an individual with repeated spontaneous abortions or thromboembolic events should suggest the possibility of antiphospholipid antibody syndrome. Awareness of the retroviral status will help in not missing-out on early diagnosis of opportunistic infections. Certain medications for other disorders may worsen headache, e.g., coronary vasodilators.
Q. What are the traps to avoid when taking a headache history?
A. To improve outcome in headache management one needs to (i) avoid the pitfalls, (ii) rule out uncommon causes, (iii) recognize conditions which can mimic migraine, (iv) investigate early and appropriately, (v) know the way to start pharmacotherapy, and (vi) utilise available nonpharmacological options.
Clinicians commonly focus on the recognition only of migraine, tension-type headache, and cluster headache. Cluster headache needs to be differentiated from other important entities in the TAC group. Primary headaches that can mimic cluster headache are supraorbital and trigeminal neuralgia, PH, and the SUNCT syndrome. A pituitary adenoma that may be impinging on the cavernous sinus can present looking like cluster headache. Carotidynia is pain along the course of the carotid artery in the neck and it is usually an excruciating pain with tenderness. This entity is not included in ICHD-3 beta but in practice, it can be seen with both migraine and cluster headache.
The first attack of migraine, if severe, may look like subarachnoid hemorrhage or acute meningitis; similarly slowly progressive secondary headaches such as idiopathic intracranial hypertension (IIH), subdural hematoma, obstructive hydrocephalus, chronic meningitis, etc. can be confused with primary headaches. Sometimes 12secondary headaches may accompany or mimic primary headaches, or can activate latent primary headache syndromes. Some neurological diseases such as demyelination or cerebrovascular disease, central nervous system (CNS) vasculitis, and veno-occlusive disorders can present with headache and lead to diagnostic confusion. Headaches may occur with sleep apnea, dementia, and retroviral infections. Cerebrospinal fluid pressure disorders, both IIH and spontaneous intracranial hypotension are often missed. Idiopathic intracranial hypertension can rarely occur without papilledema.
Many systemic disorders may be associated with headache. There are headache patients in whom you may not be able to reach the diagnosis at the first consultation. Sometimes conditions progress over time and more information comes to light or findings come-up on subsequent follow-up examination, repeat imaging (magnetic resonance imaging) or other tests. Some headaches are therefore diagnosed in retrospect.
Q. What are the areas often forgotten/missed out in a quick history?
A. Some headache conditions are not thought of in routine practice. Even in a headache clinic, it is virtually impossible to end-up asking all questions to all headache patients. Despite taking maximum care and being cautious, one may still forget to ask some relevant questions. Exhaustive questionnaires may help avoid this dilemma but they also make it difficult to establish rapport with the patient.
Ask about uncommon triggers, dietary triggers, link of the headache with menstrual periods, plans of conception, history of polycystic ovarian syndrome (PCOS) or oral contraceptive use, intake of hormonal treatment for PCOS, infertility, hormone replacement therapy, sleep related triggers, medications for other systemic problems, e.g., coronary vasodilators, antihypertensives, drugs that can raise prolactin levels. Ask about hypothyroidism, asthma, hypertension, and ischemic heart disease. Adherence to the ICHD-3 beta helps evaluate for all causes. Many of the entities included in group 4 (other primary headaches) are seen uncommonly in practice as are also some secondary headaches that do not always have a straightforward presentation.
Q. What are the clues in the history will point toward common primary headaches? When should you suspect a secondary headache?
A. There are definite clues in the history that could suggest whether a headache is primary or secondary. Red flags should alert you to the possibility of an underlying secondary headache. Sometimes the presentation of a primary headache with atypical features may raise the suspicion of a secondary headache, e.g., when patients with a typical migraine history tells you that they get double vision lately with their migraine, then think of a secondary cause because double vision would be very unusual for a primary headache. Use logic, pattern recognition, and more questions to reassure you if needed. It is important to remember that severity of pain does not help distinguish between primary and secondary headache. Recurrent disabling headaches are more likely primary and headaches with clinical clues are more likely to have a secondary cause.6
Q. What should you know about the migraine spectrum when you see headache patients?
A. Many symptoms of migraine that are not consistent with criteria for migraine with and without aura, severe migraine with cluster-like symptoms, or mild migraine looking like “tension-type headache” can be confusing for the diagnostician but is entirely to 13be expected in practice. Patients can have more than one headache type that meets “criteria” for the variants of migraine (Box 6). Biologically it makes more sense that all migraine is on a spectrum and even some forms of tension-type headache exist on the same spectrum. Many debates have failed to resolve this issue. Children in particular manifest these variants or equivalents more commonly.
Q. What are the key points to ask when you suspect the trigeminal autonomic cephalalgias?
A. You must ask about autonomic symptoms and look for signs including Horner's syndrome, unilateral lacrimation, or nasal discharge of clear fluid or stuffiness. Be sure to ask this more than once to verify the symptoms and signs, once during the formal history and again during the examination. Ask particularly about duration and if you think it is cluster headache be sure to ask about agitation or restlessness and triggering factors along with seasonal variation and a consistent time of onset.
Q. Why is examination of the headache patient so important?
A. Clinical examination is an extension of the history and is helpful at several levels. First, it affirms to the patient that they are being thoroughly evaluated and that someone has taken the time and effort to ensure they are fully assessed. It also allows the clinician to seek out general or neurological signs of secondary headache disorders and other diseases. Some primary headache disorders also can have signs. Finally, it allows the clinician to continue to assess the history, during the examination, a useful diagnostic trick.
Q. What are your objectives during the examination?
A. While examining the patient, one should think about localization. Obviously, head pain has more in common with visceral pain than somatic, but one must still think neurologically. This is very important as further investigation about secondary etiologies is directed by finding where exactly is the lesion(s) causing the problem. Sometimes, when the patient has visual signs on field examination then the localization is relatively easy, just as it is if someone has a speech disturbance or contralateral motor or sensory complaints with appropriate findings. However, if there are bilateral symptoms and findings, think brain stem origin and if there are no findings of a focal nature then get a good look at the fundi. Some conditions like IIH may only be identified through papilledema. Likewise a midline lesion in the ventricular system, such as colloid cyst may have papilledema as the only finding. Tumors in the frontal lobe, anterior temporal lobe may not have any physical findings. If you do not think localization, then you are completely dependent on imaging to sort things out.
Q. What would be a complete examination in a headache patient?
A. The purpose of examination of a headache patient is fourfold: (i) to rule out the possibility of a secondary underlying cause, even when the history is suggestive 14of a primary headache, (ii) to get some direction for the right sequence in which to order tests to confirm the diagnosis, (iii) to rule out an underlying systemic cause, and (iv) to reassure the patient and the family who are more likely to agree with the recommendations of the treating physician only after he has examined the patient. The examination can be brief but should check out the relevant areas such as the pulse, blood pressure, body temperature, tenderness over the sinuses, the temporomandibular joint, the neck, and cervical spine for tenderness, restricted movements, and neck stiffness.
It is not necessary to undertake a detailed neurological examination in every patient; but where necessary, the following parameters should be verified. Visual acuity, pupils, fundi, visual fields, extraocular muscles and eyelids, facial sensation, tongue movements, and hearing should be evaluated. Coordination of limbs, tendon reflexes, and absence of pathological reflexes such as the plantar responses must be checked out. Use the history to direct the degree and extent of the neurological examination.
Q. What are the take home messages?
A. Unlike in other areas of medicine where investigative techniques have overtaken the need for detailed history, in the headache field, one still has to practice and perfect the art of history taking in order to arrive at the right diagnosis. Eliciting a good history is all about entertaining the right suspicions, asking the right questions in the right sequence to arrive at the right diagnosis, and initiate the right treatment within the right timeframe. In spite of adherence to algorithms and criteria, the headache patient seen in practice may often be very different and challenging and you do come across headaches that are difficult to diagnose and treat. There is always a gap between what is written in the books and what is seen in practice.7
Every subspecialty has tips and tricks that you learn through experience. Headache diagnosis has an element of intuition and each specialist develops his/her own technique through experience combined with time, inclination, interest, and knowledge. Only if you enjoy seeing headache patients, will you enjoy listening to the headache history unfold through right questioning. If you look at headache diagnosis the same way as you would a puzzle, then it is no longer a frustrating branch of neurology. Through this chapter, it is our hope to convince you that headache medicine is an interesting and rewarding area of clinical neurology.
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- Osler W. Osler's “A Way of Life” and Other Addresses, with Commentary and Annotations. Durham (NC): Duke University Press; 2001. p. 378.
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- Ravishankar K. Optimising primary headache management. J Assoc Physicians India. 2006;54:928–34.