Silent Migraines - Migraine Without Headache

Introduction:

Silent migraines, also referred to as acephalgic migraines or migraines without headaches, are a migraine variant that does not manifest with the characteristic head pain. Instead, people with silent migraines experience symptoms like an aura (visual disturbances), dizziness, nausea, and heightened sensitivity to light and sound. Diagnosing silent migraines can be challenging due to the absence of a typical headache. Nonetheless, they can be disruptive and discomforting. Unlike migraines with head pain, silent migraines lack the extended headache phase but may include a prodrome phase with symptoms occurring hours to a day before the migraine, a relatively short aura phase lasting five to 20 minutes (occasionally longer than an hour), and a postdrome that can last up to a day.

What Is Meant by a Typical Aura Without Headache?

As per the International Headache Society (IHS) definition, a migraine aura refers to reversible focal neurological symptoms that occur before or during the onset of a migraine headache. These symptoms typically develop gradually over a span of five to 20 minutes and persist for less than an hour. Approximately 15 to 20 percent of people who experience migraines have aura symptoms, with visual disturbances being prevalent in over 90 percent of the cases. Common visual symptoms during an aura include photopsia (perception of flashing or shimmering lights in the visual field) and teichopsia (a visual disturbance where a person sees wavy or zigzag lines described as a fortification spectrum). In contrast, other symptoms may involve scotoma (a blind spot), visual distortion (alterations in the appearance of objects or surroundings), a sensation of heat waves, blurring, and hemianopsia (loss of vision in half of the visual field). Additional neurological symptoms may also be present.

Typical aura without headache (TAWH) is a rare form of migraine with aura, affecting approximately three percent of women and one percent of men. The diagnostic criteria for TAWH include:

1. At least two attacks meeting criteria two and three.

2. One or more fully reversible aura symptoms involving visual, sensory, or speech or language symptoms, excluding motor, brainstem, or retinal symptoms.

3. At least two of the following four characteristics:

• One aura symptom gradually spreads over at least five minutes, or two or more symptoms occur in succession.

• Each aura symptom lasts five to 60 minutes.

• At least one aura symptom is one-sided.

• The aura is followed or accompanied by a headache, with a potential lag phase lasting 60 minutes.

4. The diagnosis does not align with another ICHD-3 beta diagnosis, and transient ischemic attack has been ruled out.

5. There is no headache accompanying or following the aura within 60 minutes.

What Are the Signs and Symptoms of Silent Migraines?

The symptoms of silent migraines vary depending on the different stages of a migraine episode. These include:

1. Prodrome Phase: This is the earliest stage, which can start a few days or hours before severe symptoms like depression, difficulty concentrating, fatigue, food cravings, sensitivity to sound and light, irritability, sleep disturbances, and others. Not everyone experiences the prodrome phase before a migraine episode.

2. Aura Phase: Aura is present in about 25 percent of people with migraines. Some may experience aura without headache, which occurs in about four percent of migraine sufferers. Aura symptoms can include visual disturbances, numbness and tingling, difficulty with speech, dizziness, and temporary loss of sight and consciousness. Visual changes during aura can manifest in various ways, such as bright lights, blurring, zigzag lines, and more. A migraine aura without headache typically evolves over the first five minutes and can last up to an hour.

3. Headache Phase: During the headache phase of a migraine, people usually experience pain lasting for four to 72 hours. Silent migraine sufferers are less likely to have this headache but may encounter symptoms like nausea, neck pain, dizziness, anxiety, sensitivity to light, sound, smell, and vomiting.

4. Postdrome Phase: Approximately 80 percent of migraine sufferers experience a postdrome phase, often referred to as a “migraine hangover”. This phase occurs at the end of the headache phase and can last 24 to 48 hours. It may involve symptoms like body aches, difficulty concentrating, mood changes (depression or euphoria), dizziness, and fatigue.

What Are the Causes and Risk Factors of Silent Migraines?

The causes and risk factors include:

• Hormonal Changes: Hormonal fluctuations, particularly in women, can trigger migraines. This includes changes in estrogen levels, such as those occurring during the menstrual cycle, pregnancy, or menopause.

• Genetics: There is a genetic component to migraines, and a family history of migraines may induce migraine issues.

• Triggers: Various triggers, including certain foods (aged cheese, processed meat, and caffeine), beverages, strong odors, lack of sleep, stress, and environmental factors like weather changes, can provoke migraines.

• Neurological Factors: Migraines involve changes in brain chemicals, such as serotonin, which can lead to abnormal blood vessel constriction and dilation.

• Gender: Migraines are more common in women than in men. Hormonal fluctuations can contribute to migraines.

• Stress: High levels of stress, both physical and emotional, can be a trigger factor for migraine in some individuals.

• Other Medical Conditions: Having certain medical conditions or comorbidities, such as depression or anxiety, may increase the risk of migraines.

How to Diagnose Silent Migraines?

Diagnosing silent migraines involves a comprehensive evaluation by a doctor or neurologist. It involves:

• Medical History: A detailed medical history is taken by the doctor about the symptoms, frequency, duration, and potential triggers. The doctor may also ask about any family history of migraines.

• Physical Examination: A physical examination is performed to rule out other medical conditions causing the symptoms.

• Description of Symptoms: Silent migraines often involve aura symptoms without typical headache. Describing these aura symptoms in detail, such as visual disturbances or sensory changes, is crucial for diagnosis.

• Differential Diagnosis: The healthcare professional will rule out other conditions causing similar symptoms like transient ischemic attacks or other neurological disorders.

• Imaging Tests: Imaging tests like MRI (magnetic resonance imaging) or CT (computed tomography) scans are advised to rule out structural abnormalities in the brain.

• Blood Tests: This is conducted to check for other potential causes of symptoms, such as hormonal imbalance or inflammatory markers.

• Diagnostic Criteria: Diagnosis may also follow the diagnostic criteria provided by the International Classification of Headache Disorders (ICHD). Silent migraines are considered a subtype of migraine with aura.

• Discussion of Triggers: Identifying potential triggers for silent migraines is important. Discussing lifestyle factors, stressors, and any dietary or environmental elements contributing to the symptoms helps diagnose.

What Is the Treatment and Management of Silent Migraines?

The treatment and management of silent migraines focus on relieving symptoms and preventing future episodes. It involves:

1. Lifestyle Modification:

   • Keeping a headache diary to pinpoint potential triggers and try to minimize the exposure.

   • Getting adequate sleep reduces the risk of migraines.

   • Drinking enough water.

   • Stress management through relaxation exercises, meditation, and deep breathing.

2. Dietary Adjustments:

   • Avoiding cheese, processed meats, and caffeine.

   • Eating regular, balanced meals.

3. Medications:

   • Healthcare providers may prescribe medications such as NSAIDs, calcium channel blockers, or antidepressants.

   • OTC medications such as Ibuprofen or Aspirin may help in mild cases.

4. Non-pharmacological Treatments:

   • Biofeedback therapy can help you gain control over physiological functions that may trigger migraines, such as muscle tension.

   • Cognitive behavioral therapy (CBT) can also help manage stress and cope with the emotional impact of migraines.

5. Hormonal Therapy: In some women, hormonal changes trigger migraines. Hence, hormonal therapy may help regulate hormonal fluctuations.

6. Regular Exercise: Regular physical activity reduces the frequency and severity of migraines.

Conclusion:

Silent migraines, or acephalgic migraines, present a unique challenge as they lack the hallmark headache pain of traditional migraines. Instead, they manifest with aura symptoms like visual disturbances, sensory changes, and other neurological signs. While the exact cause is unclear, silent migraines can occur due to genetic predisposition, hormonal fluctuation, and environmental triggers. A detailed history and prompt treatment with medications and lifestyle modifications help alleviate the symptoms.