What distinguishes migraine from a sinus-related headache?
The initial presentation of sinus infection is so similar to migraine that it is often mistakenly diagnosed and treated like just another headache. However, despite overlapping symptoms, differences between the two entities can be distinguished through a careful evaluation.
Migraine is a familiar event, with or without warning symptoms (aura or prodrome). It may be gradual or abrupt in onset, moderate or severe in intensity, is often accompanied by a sensitivity to light and sound, and by nausea and vomiting. The pain may be one-sided or diffuse, limited to the front, top, or back of the head, and may often reach into the neck. It may hurt in the face area as well. Migraine may be provoked by other illnesses that affect the head or neck, such as a dental problem or respiratory or sinus infection. Migraine often subsides after several hours with the assistance of an effective rescue medication (abortive). For most, migraine is a distinct and familiar event with a predictable duration and resolution.
Sinus headache typically occurs in the area of the sinuses (see Figure 1)—in the area of the cheeks (maxillary sinus), bridge of the nose (ethmoid sinus), or above the eyes (frontal sinus). Less often it may refer pain to the top or back of the head (sphenoid sinus—see Figure 2 ). Sinus headache may occur on one side or both sides of the head and the neck is typically not involved. The symptoms are frequently worsened by bending over or coughing (as with migraine), and examination of the facial area may reveal local tenderness, redness, swelling, and possibly the presence of clear or discolored nasal discharge. Sinus disease can happen to people who suffer from migraine or to those who do not and may lead to increased migraine activity in migraine sufferers, often confusing the diagnosis.
What causes sinus headache?
Sinus headache may arise from an allergy reaction, an infection, or other obstruction. When due to allergy, it may be referred to as "rhinitis," which is often seasonal or chronic-lasting for long periods. Infectious sinusitis is due to an infection. It may be bacterial, viral, or fungal in origin, acute or chronic in duration, and with or without other symptoms such as a cough, sore throat, or fever.
Chronic allergic sinusitis may result in an infection due to the accumulation of secretions.
It is often possible to distinguish one type of sinusitis from another. For instance, allergic rhinitis often occurs seasonally and may relate to the pollen count in the spring and fall, or occurs when a dusty or contaminated home heating system starts up in the autumn. Both allergic sinusitis and viral sinusitis are characterized by a thin, watery nasal or postnasal discharge. The associated sinus congestion may impede adequate aeration of the sinuses, ultimately leading to a bacterial infection, characterized by yellowish or greenish nasal discharge, fever, malaise, etc.
What can happen if sinus infections are left untreated?
If not adequately recognized and treated, some types of sinusitis can be especially serious. For example, due to its close proximity to the brain, infection in the sphenoid sinus may easily lead to a serious central nervous system infection, injuring important nerves to the eyes and face (see Figure 2).
How are sinus-related headaches treated?
The treatment of sinusitis begins with a careful history and detailed physical examination. A review of imaging studies of the head or neck (x-rays, CT or MRI scans) may be required to make an accurate diagnosis. Direct visualization of the tissues by inserting a scope device up the nasal passages may also be necessary.
Upon determining that a headache's origin is a sinus infection, short-term antibiotics (typically less than 2 weeks) and decongestants (several days only) may be prescribed. Allergic sinusitis may respond to simple antihistamine and steroid-based nasal sprays. A chronic sinus infection may require weeks of therapy, various antibiotic regimens, or the judicious use of supportive steroid preparations. Sometimes nasal surgery is indicated to correct underlying anatomical factors.
Treatment failure may be attributed to poor compliance, e.g., skipping or prematurely stopping antibiotics or steroid nasal sprays, overusing analgesics or decongestants, and/or inappropriate self-treatments. The overuse of analgesics or decongestants may result in daily rebound headache. When related to sinus pathology this is termed rhinitis medicamentosa, though its migraine counterpart is referred to as analgesic rebound headache.
One reason confusion arises in the diagnosis of this condition is that tests are often normal. Additionally, even true sinus headaches may respond to the same medications that treat migraine, such as analgesics, over-the-counter nasal decongestants and antihistamines. The effectiveness of these medications may be due to the involvement of common pain pathways and peripheral vascular reactivity in both migraine and sinusitis.
Given the nonspecific and often overlapping features of sinusitis and migraine, treatment failure may suggest either an alternative diagnosis or multiple conditions occurring at the same time, such as migraine aggravated by sinusitis. Resistant cases of sinusitis often require the assistance of an ear, nose, and throat specialist. In addition, migraineurs may never receive an accurate diagnosis of migraine until their sinus condition has been addressed.