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Treatment depends on identifying behavior that triggers migraine such as stress, sleep deprivation, skipped meals, food sensitivities, or specific activities. Medicines used to treat retinal migraines include aspirin, other NSAIDS, and medicines that reduce high blood pressure.
The medical exam should rule out any underlying causes, such as blood clot, stroke, pituitary tumor, or detached retina. A normal retina exam is consistent with retinal migraine.
Symptoms typically appear gradually over 5 to 20 minutes and generally last fewer than 60 minutes, leading to the headache in classic migraine with aura, or resolving without consequence in acephalgic migraine. Many migraine sufferers change from scintillating scotoma as a prodrome to migraine to scintillating scotoma without migraine. The scotoma typically spontaneously resolves within the stated time frame, leaving few or no subsequent symptoms, though some report fatigue, nausea, and dizziness as sequelae.
All people who present with red flags indicating a dangerous secondary headache should receive neuroimaging. The best form of neuroimaging for these headaches is controversial. Non-contrast computerized tomography (CT) scan is usually the first step in head imaging as it is readily available in Emergency Departments and hospitals and is cheaper than MRI. Non-contrast CT is best for identifying an acute head bleed. Magnetic Resonance Imaging (MRI) is best for brain tumors and problems in the posterior fossa, or back of the brain. MRI is more sensitive for identifying intracranial problems, however it can pick up brain abnormalities that are not relevant to the person's headaches.
The American College of Radiology recommends the following imaging tests for different specific situations:
A lumbar puncture is a procedure in which cerebral spinal fluid is removed from the spine with a needle. A lumbar puncture is necessary to look for infection or blood in the spinal fluid. A lumbar puncture can also evaluate the pressure in the spinal column, which can be useful for people with idiopathic intracranial hypertension (usually young, obese women who have increased intracranial pressure), or other causes of increased intracranial pressure. In most cases, a CT scan should be done first.
Scintillating scotomas are most commonly caused by cortical spreading depression, a pattern of changes in the behavior of nerves in the brain during a migraine. Migraines, in turn, may be caused by genetic influences and hormones. People with migraines often self-report triggers for migraines involving stress and a wide variety of foods. While monosodium glutamate (MSG) is frequently reported as a dietary trigger, some scientific studies do not support this claim.
The Framingham Heart Study, published in 1998, surveyed 5,070 people between ages 30–62 and found that scintillating scotomas without other symptoms occurred in 1.23% of the group. The study did not find a link between late-life onset scintillating scotoma and stroke.
EEG testing can diagnose patients with medial temporal lobe epilepsy. Epileptiform abnormalities including spikes and sharp waves in the medial temporal lobe of the brain can diagnose this condition, which can in turn be the cause of an epileptic patient's micropsia.
The Amsler grid test can be used to diagnose macular degeneration. For this test, patients are asked to look at a grid, and distortions or blank spots in the patient's central field of vision can be detected. A positive diagnosis of macular degeneration may account for a patient's micropsia.
A controlled size comparison task can be employed to evaluate objectively whether a person is experiencing hemimicropsia. For each trial, a pair of horizontally aligned circles is presented on a computer screen, and the person being tested is asked to decide which circle is larger. After a set of trials, the overall pattern of responses should display a normal distance effect where the more similar the two circles, the higher the number of errors. This test is able to effectively diagnose micropsia and confirm which hemisphere is being distorted.
Due to the large range of causes that lead to micropsia, diagnosis varies among cases. Computed tomography (CT) and magnetic resonance imaging (MRI) may find lesions and hypodense areas in the temporal and occipital lobes. MRI and CT techniques are able to rule out lesions as the cause for micropsia, but are not sufficient to diagnose the most common causes.
MAV is not recognized as a distinct diagnostic entity. Lembert and Neuhauser propose criteria for definite and probable migraine-associated vertigo.
A diagnosis of "definite migraine-associated vertigo" includes a case history of:
- episodic vestibular symptoms of at least moderate severity;
- current or previous history of migraine according to the 2004 "International Classification of Headache Disorders";
- one of the following migrainous symptoms during two or more attacks of vertigo: migrainous headache, photophobia, phonophobia, visual or other auras; and
- other causes ruled out by appropriate investigations.
A diagnosis of "probable migraine-associated vertigo" includes a case history of episodic vestibular symptoms of at least moderate severity and one of the following:
- current or previous history of migraine according to the 2004 "International Classification of Headache Disorders";
- migrainous symptoms during vestibular symptoms;
- migraine precipitants of vertigo in more than 50% of attacks, such as food triggers, sleep irregularities, or hormonal change;
- response to migraine medications in more than 50% of attacks; and
- other causes ruled out by appropriate investigations.
Note that, in both of the above criteria, headache is not required to make the diagnosis of migraine-associated vertigo.
They add that, in patients with a clear-cut history, no vestibular tests are required. Other historical criteria which are helpful in making the diagnosis of migraine-associated vertigo are vertiginous symptoms throughout the patient’s entire life, a long history of motion intolerance, sensitivity to environmental stimuli, illusions of motion of the environment, and vertigo that awakens the patient.
Preventive treatments of migraines include medications, nutritional supplements, lifestyle alterations, and surgery. Prevention is recommended in those who have headaches more than two days a week, cannot tolerate the medications used to treat acute attacks, or those with severe attacks that are not easily controlled.
The goal is to reduce the frequency, painfulness, and/or duration of migraines, and to increase the effectiveness of abortive therapy. Another reason for prevention is to avoid medication overuse headache. This is a common problem and can result in chronic daily headache.
Long term prognosis in people with migraines is variable. Most people with migraines have periods of lost productivity due to their disease; however typically the condition is fairly benign and is not associated with an increased risk of death. There are four main patterns to the disease: symptoms can resolve completely, symptoms can continue but become gradually less with time, symptoms may continue at the same frequency and severity, or attacks may become worse and more frequent.
Migraines with aura appear to be a risk factor for ischemic stroke doubling the risk. Being a young adult, being female, using hormonal birth control, and smoking further increases this risk. There also appears to be an association with cervical artery dissection. Migraines without aura do not appear to be a factor. The relationship with heart problems is inconclusive with a single study supporting an association. Overall however migraines do not appear to increase the risk of death from stroke or heart disease. Preventative therapy of migraines in those with migraines with auras may prevent associated strokes. People with migraines, particularly women, may develop higher than average numbers of white matter brain lesions of unclear significance.
Despite the temporary nature of the vision loss, those experiencing amaurosis fugax are usually advised to consult a physician immediately as it is a symptom that may herald serious vascular events, including stroke. Restated, “because of the brief interval between the transient event and a stroke or blindness from temporal arteritis, the workup for transient monocular blindness should be undertaken without delay.” If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA. Therefore, investigation of cardiac disease is justified.
A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia. When investigating amaurosis fugax, an ophthalmologic consult is absolutely warranted if available. Several concomitant laboratory tests should also be ordered to investigate some of the more common, systemic causes listed above, including a complete blood count, erythrocyte sedimentation rate, lipid panel, and blood glucose level. If a particular cause is suspected based on the history and physical, additional relevant labs should be ordered.
If laboratory tests are abnormal, a systemic disease process is likely, and, if the ophthalmologic examination is abnormal, ocular disease is likely. However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, noninvasive duplex ultrasound studies are recommended to identify carotid artery disease. Most episodes of amaurosis fugax are the result of stenosis of the ipsilateral carotid artery. With that being the case, researchers investigated how best to evaluate these episodes of vision loss, and concluded that for patients ranging from 36–74 years old, "...carotid artery duplex scanning should be performed...as this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring, and precordial echocardiography)." Additionally, concomitant head CT or MRI imaging is also recommended to investigate the presence of a “clinically silent cerebral embolism.”
If the results of the ultrasound and intracranial imaging are normal, “renewed diagnostic efforts may be made,” during which fluorescein angiography is an appropriate consideration. However, carotid angiography is not advisable in the presence of a normal ultrasound and CT.
Treatment of migraine-associated vertigo is the same as the treatment for migraine in general.
The prevention and treatment of acephalgic migraine is broadly the same as for classical migraine, but the symptoms are usually less severe than those of classic migraine, so treatment is less likely to be required.
Palinopsia necessitates a full ophthalmologic and neurologic history and physical exam. There are no clear guidelines on the work-up for illusory palinopsia, but it is not unreasonable to order automated visual field testing and neuroimaging since migraine aura can sometimes mimic seizures or cortical lesions. However, in a young patient without risk factors or other worrisome symptoms or signs (vasculopathy, history of cancer, etc.), neuroimaging for illusory palinopsia is low-yield but may grant the patient peace of mind.
The physical exam and work-up are usually non-contributory in illusory palinopsia. Diagnosing the etiology of illusory palinopsia is often based on the clinical history. Palinopsia is attributed to a prescription drug if symptoms begin after drug initiation or dose increase. Palinopsia is attributed to head trauma if symptoms begin shortly after the incident. Continuous illusory palinopsia in a migraineur is usually from persistent visual aura. HPPD can occur any time after hallucinogen ingestion and is a diagnosis of exclusion in patients with previous hallucinogen use. Migraines and HPPD are probably the most common causes of palinopsia. Idiopathic palinopsia may be analogous to the cerebral state in persistent visual aura with non-migraine headache or persistent visual aura without headache.
Due to the subjective nature of the symptoms and the lack of organic findings, clinicians may be dismissive of illusory palinopsia, sometimes causing the patient distress. There is considerable evidence in the literature confirming the symptom legitimacy, so validating the patient’s symptoms can help ease anxiety. Unidirectional visual trails or illusory symptoms confined to part of a visual field suggest cortical pathology and necessitate further work-up.
Although the original Silberstein–Lipton criteria and the original description by Vanast make no suggestion for the exclusion of migrainous features in NDPH, the current ICHD criteria exclude patients with migrainous features. When migraine features are present, classification thus becomes problematic.
It has been reported that migraine symptoms may be present in over 50% of NDPH patients. The current criteria definition thus excludes more than half of patients with new onset of daily headache. This exclusion due to migrainous features could have adverse scientific, diagnostic, and treatment consequences.
One proposal for reclassification of the criteria is from a study conducted on retrospective analysis of the records of 1348 patients regularly treated at the headache clinic of the Department of Neurology of Santa Casa de São Paulo, Brazil, and would be the following subdivision: NDPH with migraine features and without migraine features that would allow the inclusion of all individuals present who has a daily and persistent headache from the beginning.
Another proposed reclassification of the criteria is from a study conducted as a retrospective chart review of patients seen at the Headache Center at Montefiore Medical Center in Bronx, New York, from September 2005 to April 2009. The revised criteria for NDPH definition does not exclude migraine features (NDPH-R), and three subdivisions were created and described based on prognosis: Persisting, remitting, and relapsing–remitting. Additionally, this revised criteria would not include parts C or D currently required by the ICHD diagnostic criteria for NDPH.
Most patients have persistent headaches, although about 15% will remit, and 8% will have a relapsing-remitting type. It is not infrequent for NDPH to be an intractable headache disorder that is unresponsive to standard headache therapies.
If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate." However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.
Macropsia is generally diagnosed once a patient complains of the characteristic symptoms, such as disproportionally large objects in their visual field. The Amsler Grid test can be used to diagnose macropsia, along with other visual maladies depending on the subjective disturbance reported by the patient after looking at the Amsler Grid. Outward bulging of the lines on an Amsler Grid is consistent with patients experiencing macropsisa. The New Aniseikonia Test (NAT) can quantify the degree of macropsia or micropsia independently in the vertical and horizontal meridians. The test consists of red and green semicircles on a black background with a white round fixation target. The size of the red semicircle is held constant while the green semicircle is varied in size in 1% increments. The patient wears a pair of red/green goggles so that one eye is tested at a time, and the patient attempts to determine when the semicircles are the same size. This is termed the reversal threshold and the size difference between the semicircles is reported as the degree of aniseikonia. A positive value indicates that the object was perceived bigger and thus corresponds to macropsia, and conversely a negative value indicates micropsia. The Aniseikonia Inspector contains an aniseikonia test based on the same principles as the NAT, but the test is run on a computer screen, it is based on a forced choice method, and it can measure the size difference as a function of the size of the objects. The functionality of being able to measure the size difference as function of the size (i.e. field dependent testing) is especially important when the macropsia (or micropsia) has a retinal origin.
Optic pits should be diagnosed by an eye care professional who can perform a thorough exam of the back of the eye using an ophthalmoscope.
More recently, the development of a special technology called optical coherence tomography (OCT) has allowed better visualization of the retinal layers. It has been used to demonstrate a marked reduction in the thickness of the retinal nerve fiber layer in the quadrant corresponding to the optic pit. This is not yet in standard use for diagnosis of an optic pit, but may be helpful in supporting a diagnosis.
Treatment varies for micropsia due to the large number of different causes for the condition.
Treatments involving the occlusion of one eye and the use of a prism fitted over an eyeglass lens have both been shown to provide relief from micropsia.
Micropsia that is induced by macular degeneration can be treated in several ways. A study called AREDS (age-related eye disease study) determined that taking dietary supplements containing high-dose antioxidants and zinc produced significant benefits with regard to disease progression. This study was the first ever to prove that dietary supplements can alter the natural progression and complications of a disease state. Laser treatments also look promising but are still in clinical stages.
Prenatal screening is not typically done for FHM, however it may be performed if requested. As penetrance is high, individuals found to carry mutations should be expected to develop signs of FHM at some point in life.
There is no established treatment for visual snow. It is difficult to resolve visual snow with treatment, but it is possible to reduce symptoms and improve quality of life through treatment.
Medications that may be used include lamotrigine, acetazolamide, or verapamil. But these do not always result in benefits.
Proposed diagnostic criteria for the "visual snow" syndrome:
- Dynamic, continuous, tiny dots in the entire visual field.
- At least one additional symptom:
- Palinopsia (visual trailing and afterimages)
- Enhanced entoptic phenomena (floaters, photopsia, blue field entoptic phenomenon, self-light of the eye)
- Photophobia
- Tinnitus
- Impaired night vision
- Symptoms are not consistent with typical migraine aura.
- Symptoms are not attributed to another disorder (ophthalmological, drug abuse).
"See the equivalent section in the main migraine article."
People with FHM are encouraged to avoid activities that may trigger their attacks. Minor head trauma is a common attack precipitant, so FHM sufferers should avoid contact sports. Acetazolamide or standard drugs are often used to treat attacks, though those leading to vasoconstriction should be avoided due to the risk of stroke.
Acephalgic migraines can occur in individuals of any age. Some individuals, more commonly male, only experience acephalgic migraine, but frequently patients also experience migraine with headache. Generally, the condition is more than twice as likely to occur in females than males. Pediatric acephalgic migraines are listed along with other childhood periodic syndromes by W.A. Al-Twaijri and M.I. Shevell as "migraine equivalents" (although not listed as such in the "International Classification of Headache Disorders"), which can be good predictors of the future development of typical migraines. Individuals who experience acephalgic migraines in childhood are highly likely to develop typical migraines as they grow older. Among women, incidents of acephalgic migraine increase during perimenopause.
Scintillating scotoma is the most common symptom which usually happens concurrently with Expanding Fortification Spectra. Also frequently reported is monocular blindness. Acephalgic migraines typically do not persist more than a few hours and may last for as little as 15 seconds. On rare occasions, they may continue for up to two days.
Acephalgic migraines may resemble transient ischemic attacks or, when longer in duration, stroke. The concurrence of other symptoms such as photophobia and nausea can help in determining the proper diagnosis. Occasionally, patients with acephalgic migraine are misdiagnosed as suffering epilepsy with visual seizures, but the reverse misdiagnosis is more common.