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1. a Right Homonym Hallucinations Jacqueline M.S. Winterkorn, PhD, MD Hallucinations - Definition The patient claims he sees or behaves as if he can see something that the clinician cannot see. Hallucinations - Definition Sensory perception without external stimulation of the relevant sensory organ - Simmons Lessell Conditions Associated with Hallucinations • Psychiatric • Ocular Conditions – Vitreoretinal – Visual Loss: cataract, cornea, ARMD – Emboli – Optic Neuropathy • Drugs • Migraine • Focal Hemispheric • Midbrain [Peduncular] Hallucinosis Visual Hallucinations Traditional Categories • UNFORMED – Photopsias, Phosphenes – Retinal Stimulation – Deafferentation • FORMED – Animals, People, Scenes – Cortical Visual Hallucinations Traditional Categories • IRRITATIVE – Abnormal neuronal activity – Seizure-like activity around lesion • RELEASE – Sensory Deprivation – Loss of external stimulation – Injury resulting in severe visual loss Case History • 28 y/o man on Haldol referred for difficulty reading owing to accommodative insufficiency • Otherwise normal exam 28 year old man on Haldol Hallucinations in Psych Patient “...Last Christmas when I was in the hospital, I was seeing stuff -- all kinds of stuff…” Characteristics of Psychiatric Hallucinations • Formed > Unformed • Imprecise Localization • Not lateralized • Present with eyes open or closed • Schizophrenia - complex visual hallucinations • Auditory esp. voices • Delusional Thinking • Lack insight • Controlled by antipsychotics Case History • 58 y/o nurse in good health • History of migraine with aura • Now c/o seeing brief vertical flashes in the far temporal periphery of the right eye 58 yo nurse in good health. History of migraine. 57 year old woman with history of migraine “I would see a flash “I would turn my eye a quick look out the side and it was gone “I never see a light if I don’t move my eye “Very brief -- milliseconds -- that’s how quickly it is “When I had the migraines, it was different.” Moore’s Lightning Streaks • Brief vertical comma-shaped flash • Usually in temporal periphery • Related to vitreoretinal traction as vitreous shrinks with age • Often seen upon entering dark room • Occurs with eye movements • Hallucination: seen by patient in absence of true visual stimulus Process of Vitreous Detachment 1/3 patients over 50 100% over 80 Photopsias, Photisms and Phosphenes from Vitreo-Retinal Traction • Moore’s Lightning Streaks • Nebel’s Saccadic Flick phosphenes – light flashes elicited by eye movements – deformation of posterior vitreous face • Czermak’s accommodation phosphenes – ciliary muscle pull on peripheral retina • Pressure phosphenes Mechanical stimulation of retina in blind children “If you shut your eyes and are a lucky one you may see… a shapeless pool of lovely pale colors suspended in the darkness; then if you squeeze your eyes tighter, the pool begins to take shape and the colors become so vivid that with another squeeze they must go on fire…” - Peter Pan by J.M. Barrie Other Entoptic Phenomena [Visual images produced by eye structures] • Purkinje figures - blood vessels of the eye in front of the retina near the macula • Scheerer’s phenomenon - bright “stars” or “dots” moving in squiggly fashion through vision especially when looking at blue sky (white blood cells in retinal capillaries don’t absorb blue light) • Media opacities (floaters, emboli, etc) Scheerer’s Phenomenon • Bright dots moving in squiggly paths, especially when looking into blue light • Normal phenomenon due to white blood cells moving in the capillaries in front of the retina near the macula • White blood cells appear as bright dots because blue light (430 nm is best) is well- absorbed by red blood cells, but not by white. Microemboli: Sparks appear temporally, track outward, hesitate, vanish in periphery 65 year old man s/p BRAO preceded by photopsias • Emboli • Jagged motion • Tiny • Bright • Occasionally block Case History • 23 y/o woman on BCP c/o photopsias after viral illness • Sudden onset flashing lights and bitemporal scotomata • Flickering lines persisting for months 23 yo woman sees flickering lines in bitemporal scotomas “It started April 12th… We were on my boyfriend’s truck… and I started seeing dots “Just in the light with both eyes open... “With both eyes open it’s right off to the center of everything…” 23 year old on BCP after virus c/o visual hallucinations • No prior neuro or endocrine history • Sudden onset dots and lines • Just lateral to center in each eye • Persistent for months • VA 20/20 • No RAPD • VF bitemporal defect Acute Macular Neuroretinopathy • Sudden onset paracentral scotoma • Clover-leaf, wedge-shaped dark macular lesions OU • Scotoma consistent with retinal lesions • normal FA, normal ICG • Retinal Lesion seen with red-free light • Usually young women • Hormonal? Immunologic? Bos and Deutman AJO 1975 Retinal Causes of Visual Loss • Photopsias in chorioretinal Inflammations – AZOOR acute zonal occult outer retinopathy – AIBSE acute idiopathic blind spot enlargement – MEWDS multiple evanescent white dot syndrome – MFC multifocal choroiditis – PIC punctate inner choroidopathy • Continuous photopsias in or adjacent to a scotoma Case History 67 y/o woman c/o dimness in both eyes, first the left 4 months ago, and then the right a few weeks later. During this time she had frontal HA and continuous “sparkles” in both eyes, most noticeable when reading. She has been in good health despite a 50-pack- year smoking history. Exam Acuity: 20/25 OU HVF: severely constricted OU Fundus: narrowed arterioles, disc pallor OU MRI nl ERG prolonged and reduced rod and cone responses confirms global photoreceptor dysfunction Anti recoverin Abs present Cancer Associated Retinopathy • Episodic Blurring/ Dimming of Vision • Bright photopsias (“sparkles”), mostly continuous • Photophobia/Nyctalopia • Progressive loss of acuity, color and VF • Narrowing of retinal arterioles • Vitreous cells • Affects cones and rods - ERG extinguished • May precede discovery of small cell lung Ca Case History • 76 year old woman, bilaterally pseudophakic. Complaining of flickering lights in both eyes for the past year. • Like sun flickering through Venetian blinds • Notices upon opening eyes in the morning • Continuous throughout the day • Seen in periphery • Gone in total darkness WHAT IS THE SIGNIFICANCE OF THE PHOTOPSIAS GOING AWAY IN DARKNESS? EXAM • VA 20/25 ou • AOHRR 5/6 ou • VF full • Pupils No RAPD • Motility full • Retina attached, normal discs MEDICAL HISTORY • Medical History – angina – atrial fibrillation – pulmonary embolus • Medications – Inderal – Lanoxin – Persantine DIGOXIN LEVEL 1.8 NG/ML [NL .5 - 2.0 NG/ML] Digoxin Toxicity • ERG diagnosis: Prolonged cone b-wave implicit time • Can occur at “normal” levels of Digoxin • Reversible Symptoms of Digoxin Toxicity • Flickering - light through venetian blinds • Flashing lights • Mist, haze, dark clouds or snowy vision • Decreased visual acuity/central scotoma • Decreased color vision • Yellow or green tint [Xanthopsia] • Diplopia • Pain on eye movements Digitalis [Foxglove] Characteristics of Drug-Induced Hallucinations • Formed or unformed • Not lateralized • Environmental Influences - ambient light • Frequently overlooked and ascribed to migraine or entoptic phenomena Some Drugs that Cause Visual Hallucinations • Amphetamines • Anticonvulsants • Bromocriptine • Clomid • Cocaine • Cycloplegics - atropine, cyclogel, scopolamine • Digoxin • Elavil • Inderal • LSD, Mescalin • NSAIDs • Viagra Dopamine Agonist Therapy • Treat hyperprolactinemia in Pituitary Prolactinomas • DA agonists used for chronic therapy – Bromocriptine and Cabergoline • Side effect: hallucinations • Sinemet [dopamine] for PD associated with hallucinations in 1/4 of patients Visual Toxicity of Sildenafil (Viagra) [Don’t it turn his brown eyes blue] • Patients c/o seeing blue [cyanopsia] • Also reported: HA, AION • Pathophysiology of blue vision – Viagra main action is strong blockade of phosphodiesterase type 5 in penis – Also weakly blocks phosphodiesterase 6 in retina Visual Toxicity of clomiphene citrate (CLOMID) • Photopsias – Shimmering, Pulsing, vibrating • Binocular Phenomena – ‘trailing’ of objects in periphery – palinoptic long-lasting images • Blurred Vision but normal VA, VF • mfERG nl - suggests cortical dysfunction • Not reversible - lasts for years Phosphenes in Optic Neuropathy • Visual-auditory synesthesia • Auditory - induced visual phosphenes • Seen with optic neuritis - 30% ONTT • Seen after AION 44 year old artist referred for Optic Neuritis • 6 days ago, acute loss of vision OD • Progressed over 2-3 days • No pain • Visual hallucination elicited by startling sound: auditory induced visual phosphenes Auditory induced visual phosphenes Photopsias, Photisms, Phosphenes Unformed Visual Hallucinations • Descriptions Suggest Cause – shimmering, pulsing MAR – vibrating in periphery Clomid – snow through headlights retinal ischemia – geometric cortical • Associated Symptoms – Photophobia retinal or migrainous – Scotoma chorioretinal inflammation – Headache migraine Purple Vision . Pituitary Apoplexy . Giant Cell Arteritis . Carotid Insufficiency . Ischemia Hallucinations from Sensory Deprivation • After prolonged reduction in environmental stimuli • Normal individuals develop impaired intellectual abilities • Hallucinate – Simple: lines, dots, geometric patterns – Complex: animals, people, wallpaper, architecture, bizarre scenes Charles Bonnet Syndrome Visual Hallucinations in the Elderly • Hallucinations proportional to visual loss • Hallucinations
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