s SPECIAL REPORT VISUAL DISTURBANCES IN HEADACHE Just a for the patient or a canary in a coal mine?

BY KIMBERLY M. WINGES, MD

eadache syndromes often versus those who experience involve the , without aura.4 Aura in migraine consists of recurrent and patients frequently seek Left untreated, the headache in attacks of unilateral, fully reversible eye care for symptoms that migraine lasts 4 to 72 hours and is visual, sensory, or other central nervous may or may not be related associated with at least two of the system symptoms that evolve over Hto migraine aura. Although it is following four characteristics: minutes and last less than an hour always important to evaluate these • Having a unilateral location; (most commonly 10–30 minutes). patients for ocular causes of visual • Exhibiting a pulsating quality; Aura is often unilateral and dynamic disturbances and to treat those causes, • Carrying a moderate or severe pain and involves at least one positive visual if present, ophthalmologists often face intensity; and phenomenon. It is usually followed by patients who are experiencing visual • Being aggravated by, or causing headache but can occur in isolation disturbances in the absence of visible avoidance of, routine physical without reported pain. The term ocular pathology. Primary headache activity (eg, walking or climbing ocular migraine is commonly used to disorders such as migraine with aura stairs). refer to painless, typical visual auras. produce positive visual phenomena, The headache is accompanied by More cautious usage of that term is and secondary headaches such as at least nausea and/or vomiting or by warranted, however, because it can compressive intracranial lesions and/or phonophobia.1 imply a visual migraine aura that cause visual changes due to increased intracranial pressure or mass effect on the intracranial visual pathways. It is important to distinguish between VISUAL SNOW primary and secondary headache syndromes because both the patient’s A persistent positive visual phenomenon health and peace of mind are at stake. associated with migraine but distinct from persistent migraine aura is known as visual snow.1 MIGRAINE This chronic persists in the absence of Headaches come in many forms, as acute attacks and is more frequently found in described in International Headache patients with a history of migraine. They often Society guidelines.1 Migraine is the describe the phenomenon as looking through TV second most common form of primary static or snowfall. headache disorder, behind only Visual snow is distinct from persistent migraine tension-type headache. The Global aura (Figure). Positron emission tomography Burden of Disease Study of 2015 scan studies have linked this phenomenon to ranked migraine the third-highest Figure. Visual snow is one type of chronic altered hypermetabolism in the supplementary visual cor- commonly reported by patients with a history cause of disability worldwide in both tex (lingual gyrus).2 A similar link has been found of migraine. They describe a TV static-like disruption of men and women less than 50 years in patients with chronic photophobia, linking light their entire that is constant and present even of age.2,3 Migraine is classified into sensitivity to migraine on a pathophysiologic level.3 in the absence of headache. migraine with aura (classic migraine) Although visual snow is harmless in isolation, any and without aura (common migraine). 1. Liu GT, Schatz NJ, Galetta SL, Volpe NJ, Skobieranda F, Kosmorsky positive visual phenomenon that is new should GS. Persistent positive visual phenomena in migraine. . This distinction is important because 1995;45(4):664-668. prompt visual field testing and further workup 2. Schankin CJ, Maniyar FH, Digre KB, Goadsby PJ. ‘Visual snow’ - a disorder several meta-analyses of the literature distinct from persistent migraine aura. Brain. 2014;137(pt 5):1419-1428. based on accompanying historical details as 3. Chong CD, Starling AJ, Schwedt TJ. Interictal photosensitivity associates have shown a twofold increase in the with altered brain structure in patients with episodic migraine. Cephalalgia. risk of ischemic stroke for patients described elsewhere in this article. 2016;36(6):526-533. who experience migraine with aura

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HEADACHE AND DRY EYE debilitating, instilling fear in patients during highly demanding visual tasks By Gillian McDermott, MA, Editor-in-Chief, Clinical Content, Anterior Segment such as driving because these auras interfere with the visual field. Patients with migraine often experience aura, Questionnaire-25, the Headache Impact Test, the Although more than 90% of auras photophobia, and eye pain. Investigators for a Visual Aura Rating Scale, the Ocular Surface Disease are visual, patients may experience cross-sectional survey-based study evaluated visual Index, and the Utah Photophobia Score. Investigators other phenomena such as concurrent quality of life, headache impact, aura, dry eye, and looked for correlations between patients’ responses sensations of pins and needles photophobia in 62 patients with migraine.1 Of these to the questionnaires. The researchers found that dry emanating from a point to a side patients, 17 had episodic migraine and 45 had chronic eye had the greatest negative effect on visual quality of the body or face or, more rarely, migraine. Twenty-three of the patients reported of life and headache impact. aphasia or other speech disturbances. experiencing aura, and 39 did not report aura. Other prodromal symptoms (eg, blurry Patients completed several validated 1. Ozudogru S, Neufeld A, Katz BJ, et al. Reduced visual quality of life associated vision and fatigue) may signal an with migraine is most closely correlated with symptoms of dry eye. Headache. oncoming migraine 24 to 48 hours questionnaires, such as the Visual Functioning 2019;59(10):1714-1721. before headache onset.

DIAGNOSIS presents bilaterally with intracranial total loss of vision in either or both A thorough history provides pathology, or it can refer to a retinal eyes (Figure, center). critical guidance on the differential migraine with vasospastic vision loss diagnosis and workup. Neurologists in one eye. Visual disturbances seen s No. 3: Visual Distortions/ frequently ask patients to keep a in migraine aura may be divided into . The patient’s visual headache or headache aura journal three types. perception misrepresents reality or calendar. By documenting the (Figure, right). Examples include characteristics, timing, and evolution s No. 1: Positive Visual Phenomena/ bilateral metamorphopsia, micropsia of symptoms as well as any associated Hallucinations. The patient sees things or macropsia, halos, kaleidoscopic neurologic features, patients may that are not there, including lights, or fractured scenes, sensation of be able to identify environmental patterns, or something obstructing looking through waves of heat or triggers and gauge their responses to vision. These are the classic migraine water, persistence of visual imagery treatment more accurately. Common aura descriptions of scintillating (), or loss of color vision environmental triggers include dietary scotoma or fortification spectra (achromatopsia). consumption of chocolate, red wine, (Figure, left). A migraine patient may experience sugar, or monosodium glutamate. any single or combined version of the High-stress environments, erratic s No. 2: Negative Visual Phenomena. aforementioned visual symptoms, sleep schedules, bright sunlight, strong Areas of vision are missing, such as which completely reverse, have a odors, extreme exertion, and/or homonymous field loss, constriction stereotyped pattern for each patient, medication use or overuse can also be of the visual field—often described and can change over a lifetime (see to blame. Triggers are individualized as tunnel vision—scotomas, or a Visual Snow). Visual auras can be and can change over time.

Figure. Visual disturbances seen in migraine aura. Positive visual phenomena are the most common. An object in the way of the patient’s view moves from center to periphery in a centrifugal, spreading pattern (left). Negative visual phenomena such as a missing area of visual field develop, last for 10 to 30 minutes, and then resolve (center). Visual distortions or illusions happen when the patient perceives a normal scene as if it were fractured, underwater, or otherwise altered, often in a dynamic pattern (right).

JANUARY/FEBRUARY 2020 | RETINA TODAY 55 s SPECIAL REPORT

By definition, the diagnosis symptoms, such as slurred speech, CONCLUSION of isolated migraine and other hemiparesis, Horner syndrome, Many eye care providers primary headache syndromes or cranial nerve palsy. Although are undertrained in headache requires that there be no causative complex migraine can produce classification, but knowing the basic pathology on diagnostic evaluation. these symptoms in a recurrent features common among patients The examination of a patient fashion, targeted neuroimaging with associated visual disturbances presenting with headache and visual and a neurology workup should be and recognizing the warning disturbances should therefore include performed to exclude ischemic or signs of secondary headache are careful documentation of BCVA and embolic stroke from carotid artery critical to making clinical decisions. color vision, assessment for a relative atherosclerosis, artery dissection, Prompt referral to an emergency afferent pupillary defect, and a dilated arteriovenous malformation, or department, a neurologist, or a fundus examination to identify retinal intracranial aneurysm; neuro-ophthalmologist may be or optic nerve pathology indicating • Persistent vision loss or positive visual necessary when the diagnosis or a causative structural lesion. Both phenomena that do not fully resolve; management strategy is uncertain. n confrontation and formal visual • Onset of in patients older field testing is highly recommended than 50 years of age; 1. Headache Classification Committee of the International Headache Society (IHS): The International Classification of Headache Disorders, 3rd edition. to identify optic neuropathy or • Dramatic change in the character or Cephalalgia. 2018;38(1):1-211. homonymous defects, localizing the worsening severity of migraines or 2. Steiner TJ, Stovner LJ, Vos T. GBD 2015: migraine is the third cause of defect posterior to the chiasm. OCT migraine aura; disability in under 50s. J Headache Pain. 2016;17(1):104. 3. GBD 2015 Neurological Disorders Collaborator Group. Global, regional, imaging of the macular ganglion cell • Transient monocular vision loss, and national burden of neurological disorders during 1990-2015: a system- layer and retinal nerve fiber layer may often described as a curtain over atic analysis for the Global Burden of Disease Study 2015. Lancet Neurol. help to localize and obtain a baseline vision and usually lasting only a few 2017;16(11):877-897. 4. Hansen JM, Charles A. Differences in treatment response between migraine of optic nerve structural changes, minutes before complete resolution. with aura and migraine without aura: lessons from clinical practice and RCTs. especially if optic nerve atrophy is This phenomenon is indicative J Headache Pain. 2019;20(1):96. suspected. of amaurosis fugax and requires a retinal and cardiac workup for RED FLAGS embolic stroke; and KIMBERLY M. WINGES, MD When do a patient’s visual • Significant associated systemic n Comprehensive and Neuro-Ophthalmologist disturbances and headache warrant symptoms such as scalp tenderness, n Assistant Chief of Surgery for Clinical further workup? Several situations jaw claudication, and arthralgias that Operations, VA Portland Health Care System, should raise concern about a may accompany transient vision loss Portland, Oregon secondary headache syndrome: or diplopia with headache. These n Assistant Professor of Ophthalmology and • Homonymous visual field defects; require an emergency workup for Neurology, Casey Eye Institute, Oregon Health & • Loss or alteration of consciousness; giant cell arteritis and immediate Science University, Portland, Oregon • Concurrent neurologic signs or empiric steroid treatment. n [email protected] n Financial disclosure: None

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