Headache is a common symptom in children and adolescents that leads to a pediatric clinic consultation. Although migraine and tension-type headaches are more commonly encountered, other primary headache disorders that are typically encountered during adulthood such as cluster headache (CH) can also be seen in the pediatric population. The unusual characteristics of these headache syndromes can be alarming, and it is critical that secondary causes of headache first be ruled out. A primary headache disorder is defined by its clinical features, the lack of identifiable cause after thorough history, physical, and neurological examinations, and being caused by overactivity or stimulation of pain-sensitive structures in the head and neck and genetic vulnerability. A secondary headache disorder is a headache due to an underlying disorder or disease process such as meningitis, tumor, or head trauma.
The evaluation of a child with an unusual headache symptom starts with a detailed history and examination, specifically looking for red flags that suggest possibility of a secondary headache. Investigations such as neuroimaging may be required when indicated by the presence of a red flag (see article on life-threatening headaches by Dalvi and Sivaswamy1). In the absence of secondary headache, a diagnosis of primary headache disorder can be made and an attempt to classify the primary headache disorder must be pursued. Recognition of these rare primary headache disorders is important as effective therapy can be very specific. This review focuses on three groups of uncommon pediatric headache syndromes: trigeminal autonomic cephalalgias (TACs), cranial neuralgias, and other primary headache disorders. Each of these groups consist of specific headache disorders and the review emphasizes those that have clinical implication for children and adolescents.
Trigeminal Autonomic Cephalalgias
TACs are a group of primary headache disorders characterized by severe, repetitive, brief, unilateral head pain accompanied by autonomic symptoms. The autonomic symptoms are ipsilateral to the headache and can be at least one of the following symptoms or signs: conjunctival injection and/or lacrimation, nasal congestion and/or rhinorrhea, eyelid edema, forehead and facial sweating, forehead and facial flushing, sensation of fullness in the ear, and miosis and/or ptosis. The pain in TACs is usually located in the orbital, supraorbital, and/or temporal regions. TACs include CH, short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT), short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms, paroxysmal hemicrania (PH), and hemicrania continua (HC).2 Although they all share similar symptoms, they are notably distinct in the duration and frequency of the headache attacks and their response to specific treatments. A convenient way to remember these disorders is that the longer the name of headache is, the shorter its duration and the attacks are more frequent.
Secondary mimics of TACs include intracranial mass lesions especially in and around the pituitary gland and posterior fossa and vascular lesions, hence it is imperative to conduct a brain magnetic resonance imaging (MRI) as part of the evaluation.3
CH is the most common type of TAC and typically has a male preponderance with average age of onset in the third or fourth decade.4,5 It is classically described as a headache that occurs in clusters of attacks, about 1 to 8 times per day; recurs daily or near daily for weeks to months; and has separated headache-free periods that may last for months to years. This excruciating pain typically awakens a patient from sleep; usually within 2 hours of falling asleep and can last from 15 to 180 minutes. During a cluster attack, the patient is restless and prefers to pace the room rather than lay down.3
Although uncommon in children and adolescents, onset of CH younger than age 10 years have been reported.6,7 Childhood onset CH also shows male preponderance and clinical features that resemble adult onset CH.6,7 Differentiating cluster headache from migraine can sometimes be challenging as pediatric migraine attacks can be associated with autonomic symptoms; cluster headache may also be accompanied by photophobia and phonophobia.8,9 Clues to differentiate pediatric CH from migraine include (1) duration of attacks (CH are usually shorter than migraine); (2) location of pain (in CH, the head pain is one sided and the autonomic symptoms is lateralized to the site of head pain. In migraine, the head pain can be bilateral or alternating unilateral); (3) autonomic symptoms tend to be more prominent in CH than migraine; and (4) child's behavior during CH attack is different from migraine. Children suffering from migraine will typically lay down and sleep, whereas those with CH are usually restless and cannot keep still.
Common triggers for adult CH are alcohol, elevated environmental temperature, and smell of volatile substances. Pediatric cluster headache can be triggered by secondhand smoke and warm environment.10,11
Although there are limited data available regarding pediatric CH, acute treatment options include inhalation of 100% oxygen and subcutaneous sumatriptan, intranasal sumatriptan, and intranasal zolmitriptan. Oral “triptan” (serotonin agonists, which as a group tend to end in the word triptan) formulations should be avoided as they do not work quickly to terminate the excruciating pain. When CH becomes chronic, as defined by attacks occurring for more than 1 year with or without remission, preventive treatment is needed. Verapamil, topiramate, and melatonin are reasonable preventive therapy options.3,11
PH is a type of TAC that resembles CH with attacks of unilateral temporal and/or supraorbital pain with autonomic symptoms. The attacks of pain are shorter in duration than CH; they last for 2 to 30 minutes and occur more frequently, at least 5 per day.2 As it is in adults, PH is rare in children, with the youngest reported age at 3 years.12 It does not have male preponderance. In children, PH does not have circadian or predominant nocturnal attacks and is not associated with restlessness or agitation.13 Triggers in adults are stress, exercise, and neck movement; in children, physical effort rather than emotional stress can be a trigger.13,14 The hallmark and distinguishing factor for this syndrome is its complete and absolute response to the medication indomethacin. When treatment is initiated, resolution of headache typically occurs within 2 to 3 days of effective dose. Due to its gastrointestinal side effects, H2 blockers or proton pump inhibitors should be given when starting indomethacin treatment. In adults, the typical trial dose is 25 mg three times daily, and if needed can be increased up to 75 mg three times daily to assess the response to indomethacin.
Short-lasting Unilateral Neuralgiform Headache Attacks with Conjunctival Injection and Tearing
SUNCT is rare in children and adolescents and the limited literature available is in the form of case reports. Age range of pediatric patients with this headache disorder is between 5 and 15 years.15,16 These are ultrashort paroxysmal headache attacks lasting only for seconds. However, they can recur from once up to 100 times per day. The pain is described as stabbing, burning, or electric-like and can occur as a single stab, series of stabs, or saw tooth pain pattern.2 As the name implies, the headache in SUNCT is always accompanied by conjunctival injection and tearing. It is important to note that there can be a delay in the onset of the headache from the appearance of the conjunctival injection or tearing. The first-line therapy is lamotrigine. Slow titration to avoid serious side effects is required and therapeutic dose ranges may be 100 to 400 mg/day. There are also reports of effectiveness of topiramate and gabapentin.3
HC is another rare condition in the pediatric age; however, it is one of the indomethacin-responsive headaches. Although rare in children, it is noteworthy that adults with HC report that their headaches started during childhood suggesting that HC is likely underdiagnosed in the pediatric population. HC is characterized by continuous one-sided headache that does not switch sides and present for at least 3 months. There is a constant baseline mild to moderate head pain with exacerbations of more severe pain lasting 30 minutes to 3 days. With pain exacerbation, autonomic symptoms ipsilateral to the headache can occur.3 Similar to PH, HC responds unequivocally to indomethacin and this treatment trial is necessary to clinch the diagnosis.3
Cranial neuralgias (CN) consist of head and facial pain disorders in the anatomic distribution of the cranial nerve that is affected. Included in this group of painful cranial neuropathies are trigeminal, glossopharyngeal, and occipital neuralgias. The diagnosis of CN is only given after evaluation to exclude demyelinating disorders, vascular malformations, tumors, and inflammatory processes has been completed and shown to be negative.
Trigeminal neuralgia (TN), previously called tic douloreux, is the most common CN. It is characterized by recurrent, unilateral, brief, electric shock-like pain, most often in the second and third divisions of the trigeminal nerve. The first division of the trigeminal nerve is less commonly involved. It is severe and can last from a fraction of a second to 2 minutes. It can be triggered by innocuous stimuli to the face such as touching the nose and chin; or washing the face, brushing the teeth, or exposure to a breeze. When extremely severe, it can evoke facial muscle contraction on the affected side; hence, the term tic douloreux.2 Reports of TN in children are rare with the youngest child reported at age 5 years.17 TN can be idiopathic or secondary, usually due to compression of the nerve root by an aberrant vascular loop. Secondary causes in children include Chiari I malformation and brain tumors. As patients with multiple sclerosis have an increased risk of developing TN and more pediatric cases of multiple sclerosis are reported, it is important to consider this diagnosis especially when the pain occurs bilaterally.18 Treatment of choice for TN is carbamazepine, typical adult doses of 100 to 200 mg three times per day. For those who are refractory to medical treatment, surgical release of the vascular loop can be an option.
Glossopharyngeal neuralgia (GN) is described as a severe, transient, stabbing, one-sided pain in the ear, base of the tongue, tonsils, and/or beneath the angle of the jaw. The intense pain can last from a few seconds to 2 minutes. Swallowing, coughing, talking, or yawning can trigger the attack.2 The paroxysms of pain can have serious consequences such as weight loss, reflex bradycardia, and syncope. Like TN, it necessitates evaluation to exclude posterior fossa tumors, demyelinating disorders, and neurovascular compression. Surgical decompression of Chiari I malformation in an 8-year-old child with GN has been described as resulting in resolution of symptoms.19 If idiopathic, pharmacologic treatment is similar to TN.
Occipital neuralgia (ON) is characterized by unilateral or bilateral shooting or stabbing pain localized in the posterior aspect of the scalp in the distribution of the greater, lesser, and/or third occipital nerves. As is the case in other CNs, the pain of ON occurs in paroxysms, which last for a few seconds to minutes and are very severe in intensity. An interesting aspect of ON is the presence of tenderness over the affected branches of the occipital nerve or the presence of dysesthesia during stimulation of the affected area of the scalp and/or hair such as during brushing of the hair. Treatment involves local anesthetic blockade of the affected nerve.2 Physical therapy directed to the neck, warm/cold compresses over the affected area, and massage are conservative measures that can also be effective.
Other Primary Headache Disorders
A definitive diagnosis of the following disorders can only be made after appropriate imaging has excluded secondary headaches that may mimic these disorders. Examples of such secondary causes can be brain tumors, Chiari malformation, temporomandibular joint pathology, or cervical spine disease.
Primary Stabbing Headache
Historically, primary stabbing headache (PSH) has been called ice-pick headache, “jabs and jolts,” “needle in the eye” syndrome, ophthalmodynia periodica, and sharp short-lived head pain. It is an idiopathic headache disorder characterized by a transient and localized single stab or series of stabs of pain in the head. Each stab can last up to a few seconds and can recur throughout the day.2 Compared to TAC, PSH is not associated with cranial autonomic symptoms. There is variability in the distribution of the pain, including the orbital/supraorbital, frontal, temporal, parietal, vertex, or occipital regions. The stabs may move from one area to another, in either the same or opposite hemicranium. In pediatric studies, the mean age of onset is 9 years.20,21 Adult PSH appears to be associated with migraine; however, this association is not as clear in children. For those who have infrequent and short duration of pain, pharmacologic treatment is futile and reassurance is sufficient. However, for those with longer and more frequent headaches, indomethacin can be initiated. Based on adult studies, response of PSH to indomethacin is inconsistent. In pediatric studies, paracetamol and amitriptyline have been used.20,21
Neck-Tongue syndrome (NTS) is a headache disorder characterized by brief episodes of severe neck and/or occipital pain accompanied by ipsilateral sensory or motor symptoms of the tongue that is triggered by an abrupt movement or rotation of the head. A recent systematic review showed that the onset of NTS is in the pediatric age group with a mean age of onset at 16 years. The majority of the cases reported pain only in the neck followed by pain in both the neck and occiput and lastly, occiput alone. The pain generally is severe and can last a few seconds up to several minutes. Sensory tongue symptoms in the form of numbness, tingling, or both are more common than motor symptoms. Motor tongue symptoms are described as pulling or twisting and abnormal posture or stiffness. Head and neck injuries such as a fall off a horse and neck trauma in gymnastics are conditions reported to have started the episodes of NTS.22
The proposed mechanism is related to the temporary subluxation of the lateral atlantoaxial joint causing C2 ventral ramus to become impinged against the bone, causing the ipsilateral neck/occiput pain. The tongue involvement is due to the hypoglossal afferents entering the central nervous system through the C2 and C3 ventral rami.22,23 As such, it is challenging to demonstrate this degree of instability as it will require axial CT scanning while the neck is rotated to its maximum degree and hence routine investigation is not recommended. In general, NTS is brief and infrequent so it does not require treatment; among those with more frequent and severe episodes, activity modification, use of a cervical collar, and physical therapy can be recommended.
Red Ear Syndrome
Red ear syndrome (RES) is a rare condition consisting of recurrent attacks of burning ear pain associated with marked reddening of the entire ear (Figure 1). It typically occurs as a unilateral ear pain. However, there are also reports of pain involving both ears. The pain is commonly located over the pinna of the ear and may radiate toward the cheek and mandible or the occiput. Although RES can occur spontaneously, it can be triggered by rubbing the ears, heat, physical exercise, neck movements, chewing, or brushing of hair. There are reports suggesting that RES is associated with migraine and TACs.24,25 A pediatric study showed that RES occurs more frequently in children with migraine and suggested that RES is a highly specific sign for migraine.25 There are no reliable data to support effective treatment of RES.26 Most medications used are similar to treatment of primary headache disorders such as amitriptyline, gabapentin, indomethacin, propranolol, verapamil, and use of ice pack.
An attack of red ear syndrome with reddening of the ear triggered by rubbing the ear.
Hypnic headache (HH) is a recurrent headache that occurs only during sleep and causing awakening; hence, it is also called an “alarm clock headache.” The duration of headache is at least 15 minutes and up to 4 hours and is not associated with any other symptoms or restlessness.2 It typically occurs in the elderly but may occur in children, too. It is extremely rare in children; a review of HH in childhood described only five patients.27 In these five pediatric patients, between ages 7 and 11 years, two had a family history of migraine. Most patients described pain as severe and were able to return to sleep after pain relief. There was no recurrence of headache upon awakening in the morning. Due to concerns of secondary headache, all underwent brain MRI studies, which were normal. Except for one who received acetaminophen, no acute treatment was initiated. Two patients used melatonin for preventive treatment, which reduced headache frequency and severity.27