Clinicians diagnose migraines by whether a patient experiences at least three of four phases, which include predrome, aura, headache and prodrome. Acephalgic, or silent, migraines do not have the headache phase, which makes them difficult to diagnose. Migraines with a headache are the most prevalent, but any type of migraine with aura may be an acephalgic migraine.
Significance
Roughly $15 billion is spent each year on migraine diagnostics, medication, emergency room visits and lost work productivity, according to a report published in June 2005, in the American Journal of Managed Care. Since acephalgic migraines are difficult to diagnose, they contribute a high proportion to diagnostic testing. Typically, visual distortions are pronounced in silent migraines, which requires extensive neurological testing to rule out other more severe causes. Migraines are listed as the 19th ranked disease causing disability by the World Health Organization.
Identification
Migraine type is determined by the primary symptoms experienced. Secondary symptoms are different with each individual. All migraine subtypes can be acephalgic if they lack the headache phase. Each phase of the migraine can be identified by typical migraine symptoms The predrome involves early warning signs associated with the migraine. These signs may include light, smell, or noise sensitivity. The second phase, auras, entails color manifestations, blurred vision and temporary blindness. Headaches do not occur in acephalgic migraines. The prodrome may include a dull throb, sense of nausea or fatigue. Once a migraine has begun, sleep is typically aborts the migraine.
Causes
Dr. Steven Ofner, an ophthalmologist in Eugene, Oregon, indicates that blood vessel dilations in the visual cortex or around the eye typically produce the visual disruptions common in acephalgic migraines. Constriction of blood vessels in other parts of the brain can produce predrome and prodrome symptoms. In acephalgic migraines, specifically, constrictions are small, which prevents pain receptors from recognizing the constriction and triggering the typical headache phase of a traditional migraine.
Prevention
Individuals must identify their unique migraine triggers in order to prevent acephalgic migraines. Writing down all of activities, including any powerful odors, lights, sounds or food allergens present before the migraine can help identify the commonalities. Avoiding migraine triggers is the simplest preventative action. Otherwise, physician-guided medical treatment is an option.
Treatment
Primary treatments to treat acephalgic migraines are depression, seizure or beta-blocker medications, according to the National Headache Foundation. Over-the counter migraine medications only treat pain associated with migraines. Since most acephalgic migraine sufferers don't experience pain, over-the-counter remedies do not treat typical acephalgic migraine symptoms.
Beta-blockers improve blood circulation throughout the body by preventing constrictions from occurring. Beta-blockers are usually the first type of preventative medication prescribed for migraines; however, people who have any circulatory issues or a history of heart trouble must take another migraine preventative. Epilepsy medication raises the neuronal threshold for blood constrictions to prevent neurological symptoms that produce acephalgic migraine. MayoClinic.com indicates that depression medications raise the body's pain threshold to stop pain, but the reason that depression medication stops migraines is still unknown.
