Silent Signals: A Case Study of Migraine Aura without Headache and Its Diagnostic Challenges

Abstract

Acute acephalgic migraine is a phenomenon where the patients have typical aura symptoms: visual disturbances, sensory changes, or speech impairment without associated pain headache, which is rare, underdiagnosed, and often misdiagnosed, leading to unnecessary diagnostic testing and anxiety in the patients. We present here a case of a 38-year-old woman who reported isolated visual disturbances without any history of migraines or headaches. The clinical presentation, process of diagnosis, and therapeutic strategies for acephalgic migraine management shall be presented. Further, we will review the literature concerning the pathophysiology, triggers, and treatment options for this peculiar condition.

Introduction

Migraines are primarily characterized by throbbing headaches, but a percentage of people experience migraine aura without the headache. Known as acephalgic migraine, this is a particularly challenging diagnosis since the hallmark migraine pain is missing. The visual disturbances characteristic of a migraine aura can be misdiagnosed as another serious neurological condition like stroke or transient ischemic attack (TIA).

The clinical presentation and management of a case of an isolated patient with visual symptoms are discussed to provide insight into the diagnostic approach and the treatment options for acephalgic migraine.

Patient Information

1. Age/Gender: 38-year-old female

2. Occupation: Office worker

3. Chief Complaint: Recurrent visual disturbances

4. History: The patient, a previously healthy 38-year-old woman, presented with complaints of episodic visual symptoms that began suddenly one month before her visit. She described seeing shimmering zigzag lines in both visual fields, which would last for about 20 to 30 minutes before resolving spontaneously. These episodes occurred approximately twice a week. The patient denied any associated headaches, nausea, or photophobia during or after the episodes. She had no previous history of migraines, significant medical conditions, or family history of migraines or neurological disorders. The patient’s lifestyle included working long hours in front of a computer, with frequent screen exposure and minimal breaks.

Diagnostic Workup

Since the signs presented are visual, and she had no headache, the initial clinical suspicion tilts toward the possibility of transient ischemic attacks or an ocular pathology, like retinal detachment.

Initial Evaluation and Neurological Examination

The patient had undergone a detailed neurological examination. Her cranial nerve function, muscle strength, sensory response, and coordination were all normal. No ophthalmologic abnormalities were noted, and her vision was not affected.

Imaging

A non-contrast CT scan of the brain was performed to rule out any acute cerebrovascular event. The results were unremarkable, with no evidence of ischemia or hemorrhage. An MRI of the brain was also obtained, which showed no structural abnormalities.

Electroencephalogram (EEG)

To exclude the possibility of focal seizures, an EEG was conducted. The results were normal, showing no epileptiform activity.

Blood Work

Routine blood tests, including a complete blood count, electrolyte panel, and tests for thyroid function, were within normal limits. Coagulation studies were also negative, eliminating concerns about clotting disorders.

Diagnosis

The clinical team thus did consider a diagnosis of acephalgic migraine or migraine aura without headache, although a host of other serious conditions had already been considered and indeed excluded. The patient's visual disturbances were very typical of migraine aura, consisting of shimmering zigzag lines (often termed a "fortification spectrum"). Headache is not always present in migraine aura, though it is far from a ubiquitous feature; again, this case could be classified under migraine aura.

Diagnostic Criteria

The diagnosis was made based on the International Classification of Headache Disorders (ICHD-3) criteria for migraine aura without headache:

Fully reversible visual symptoms.

No motor weakness.

No headache during or following the aura.

Management and Treatment Plan

Once the diagnosis of acephalgic migraine was established, the focus shifted to managing the patient’s symptoms and preventing future episodes. Lifestyle modifications and preventive therapy were key components of the treatment plan.

Lifestyle Modifications

The patient was advised to make adjustments to her work habits, particularly by taking regular breaks from prolonged screen time. She was also encouraged to improve her sleep hygiene, manage stress, and maintain hydration, as these are known triggers for migraine attacks.

Pharmacologic Therapy

Since the patient's aura episodes were frequent and significantly impacted her quality of life, a preventive treatment strategy was considered. Low-dose propranolol, a beta-blocker commonly used for migraine prevention, was prescribed. Other preventive options, such as antiepileptic drugs or calcium channel blockers, were discussed, but propranolol was chosen due to its efficacy and side effect profile.

Follow-Up Plan

The patient was scheduled for follow-up visits to monitor her response to therapy and evaluate any changes in her symptoms. She was also advised to maintain a headache diary to track potential triggers and assess the frequency of her visual disturbances.

Timeline of Case

1. Month 1: First episode of visual disturbances (zigzag lines).

2. Month 1-2: Recurrence of visual symptoms twice a week.

3. Month 2: Initial evaluation and neurological examination (normal).

4. Month 2: CT scan of the brain (normal).

5. Month 2: MRI of the brain (normal).

6. Month 3: Diagnosis of acephalgic migraine.

7. Month 3: Start of preventive treatment with propranolol.

8. Month 4: Follow-up visit: significant reduction in visual episodes.

9. Month 6: Patient reported complete resolution of visual disturbances.

Discussion

Diagnosis of an acephalgic migraine-that is migraine aura without headache-is difficult in a patient who has never experienced migraine or headache. Visual disturbances such as those seen with acephalgic migraine may simulate a TIA, seizure, or retinal pathology and often lead to extensive- and sometimes unnecessary-testing. Clinical acumen and history-taking played important roles in this correct diagnosis.

Pathophysiology of Migraine Aura without Headache

The exact pathophysiology of migraine aura without headache is not fully understood. Still, it is thought to involve cortical spreading depression (CSD), a wave of depolarization that spreads across the cortex and leads to the transient neurological symptoms seen during the aura. In cases where headache does not accompany the aura, it is speculated that the CSD does not activate the trigeminal vascular system, which is responsible for the pain associated with migraines.

Triggers

Common triggers for migraine aura, both with and without headache, include:

Stress: Increased workload and lack of breaks.

Sleep disturbances: Poor sleep hygiene can trigger migraines.

Visual stimuli: Prolonged exposure to screens.

Dietary factors: Skipping meals or consuming specific foods.

Management

Similar considerations as for the typical migraine guide therapeutic efforts for the acephalgic type. Beta-blockers, calcium channel blockers, and antiepileptic drugs constitute the mainstays of pharmacologic therapy. Nonpharmacologic measures—lifestyle modifications—can not be undervalued as an aid in reducing the frequency of episodes.

Conclusion

Acephalgic migraine is usually overlooked or misdiagnosed, despite a classic well-documented presentation. The present case reiterates that acephalgic migraine should be considered in patients who complain of isolated visual disturbances, particularly in the context of normal diagnostic tests. Early recognition, coupled with lifestyle modifications and preventive therapy, improves the quality of life of these patients significantly.
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