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National MS Society Midwest Teleconference How MS Affects Vision National MS Society Midwest Teleconference How MS Affects Vision Jonathan C. Calkwood MD Medical Director Schapiro Center for Multiple Sclerosis Why are Vision Disorders Important in MS •Impairs function in persons with MS •Vision problems are a common first symptom in MS which helps with early diagnosis of MS •MS responds better to early treatment •The optic nerve is a window into the brain for research to understand MS and treatment effects on nerve cell death and disability 2 Vision Problems in MS Common manifestations of MS Often heralds the onset of MS Compromises activities of daily living Causes and contributes to disability Sight is Precious Emotional Impact of Vision Problems • “Sudden onset of double vision, poor contrast, eye pain, or heavy blurring is frankly terrifying” • “The knowledge that vision may be compromised makes people with MS anxious about the future” • “Fortunately, the prognosis for recovery from many vision problems associated with MS is good.” http://www.nationalmssociety.org/Brochures-On%20Vision.asp MS VISUAL PROBLEMS FALL INTO THREE MAIN ANATOMICAL CATEGORIES 1.DISORDERS OF SIGHT The AFFERENT visual system is composed of the retina, optic nerve, optic tract and occipital cortex. Visual field and visual acuity deficit's, color vision and contrast vision loss 2. DISORDERS OF CONTROL OF THE EYE MOVEMENTS The EFFERENT visual system includes the frontal cortex, brainstem and cranial nerves Diplopia, Nystagmus, Oscillopsia. 3. DISORDERS OF THE BRAIN The visual PROCESSING functions occur in occipital cortex and association areas. Common symptom in MS •Optic neuritis •Causes painful vision loss •70% will have it at some time in their MS •30 -50% as presenting event •Residual symptoms •contrast sensitivity and color vision loss, •Impaired visual acuity or peripheral field 6 Common symptom in MS •Brain stem disease •Up to 50% will have brainstem problem as first event •Convergence insufficiency •Reading problems •Blurred double vision, eye strain while reading •Nystagmus/ Oscillopsia 7 Why Early Diagnosis and Treatment is Important • MS active in the CNS years before first symptom – In the past patients were started on treatment after 2nd attack – wait and see approach • Research data supports early treatment benefit – expectations of improved disability, exacerbations and MRI changes on treatment, the earlier the better. – Atrophy and loss of brain cell occurs early in MS • Early diagnosis can be aided by appropriately identifying visual problems that are often the first symptom of MS Research Implications • Vision disorders may help define new treatments in MS – optic nerve is a window to the brain • OCT = optical coherence tomography – Measures thickness of the nerves in the back of the eye – Correlates with visual function and MRI changes and progression of disease – May be predictive – may help define treatment response – Help identify new treatments in MS that will be neuroprotective Optic Nerve: a Window to the Brain Optic Neuritis Symptoms are usually obvious But may be subtle in some Optic Neuritis Treatment of Optic Neuritis • Similar to the treatment of an exacerbation – High dose IV Steroids – Never oral steroids without IV first • Results in faster recovery • Does not improve ultimate recovery Residual symptoms of optic neuritis • Visual acuity/field loss recovers well • contrast sensitivity and color vision loss – Impaired visual acuity/field » LCLA chart » Repeated attacks (less likely to recover fully) or slow worsening (late disease) Prognosis of vision loss in Optic Neuritis • Typical course mirrors MS attack – Steroids speed up recovery but does not improve ultimate recovery • Treatment with DMTs may slow development of vision problems • Most patients have good recovery from optic neuritis • Contrast and color vision problems are common • An insidious optic neuropathy without acute optic neuritis can compromise vision in many people with MS Optic Neuritis Study Group Ten Year Visual Outcome Most patients • 20/20 or better 74% retained good to • 20/25 -20/40 18% excellent vision more • 20/40 – 20/200 5% than 10 years after an attack of optic • Less than 20/200 3% neuritis. Beck RW, et. al. Am J Ophthalmol 2004 Jan;137:77–83 Tests of Peripheral Vision • Peripheral field accounts for 90% of our vision • Peripheral vision loss may not be noticed • Visual field can be accurately measured over time – Progression of disease – Response to treatment Visual Field • Maps peripheral vision • Very sensitive for change – Identify problem – Progression of disease – Response to treatment Contrast Sensitivity • Contrast loss is common residual of resolved ON • Office based screening test – Inexpensive – Quick and easy – Sensitive (77% asymptomatic CDMS) – Moderate specificity • Research tool – Clinical trials – MSFC LJ Balcer et. al. Multiple Sclerosis (2000) 6, 163±171 Low-Contrast Sloan Letter Charts OCT Measures Density of Nerve Cells in the Eye Density of retina nerve cell before the optic neuritis. Each Scan is compared to baseline Patient has acute optic neuritis with swelling of retina nerve cells noted in green. Two months later patient has lost retinal nerve cells indicated in red. Patient continues to lose nerve cells. Some recovery may sometimes be seen by about 6 months. On average, Optic Neuritis results in a 20% loss of retinal nerve cells Double Vision Internuclear Ophthalmoplegia • INO Common in MS • Brainstem Lesion • Double to opposite side • Eye won’t move in toward the nose • Usually other symptoms (variable) – Diziness or balance – Facial weakness – Slurred speech Nystagmus Instability of the eyes – Rhythmic movements – Jerk, Pendular or Rotary Brainstem or Cerebellar Symptoms – Oscilopsia • jiggling visual environment – Trouble focusing – Impaired balance Suppression over time Ocular inflammations associated with MS • Anterior Uveitis – Corneal deposits – Red eye – Eye pain – Light sensitivity • Least common in MS • Bechets, syphilis, Lyme, sarcoid • Rheumatologic disease • Different treatment – Most >20/30 vision Inflammation of Blood Vessels • Painless vision loss – Visual acuity – Visual field • Modest recovery – 6-18 months • Unusual in MS – Cat Scratch Fever Symptom Treatment of vision loss in MS • Contrast sensitivity – Tinted glasses • Double vision – Prism glasses and tape patch • Nystagmus/Oscillopsia – Alzheimer medication • Sever vision loss – Occupational therapy and low vision aids Living with Low Vision Adapting Your Environment Occupational Therapy Low Vision Aids • Closed circuit television (CCTV) • Computers and eReaders • Electronic Magnifiers Low Vision Aids • Optical Devices Low Vision Resources • American Foundation for the Blind, 800-AFB-LINE, www.afb.org • American Nystagmus Network, www.nystagmus.org • American Printing House for the Blind, 800-223-1839, www.aph.org • The Low Vision Gateway, www.lowvision.org • The Lighthouse, 800-829-0500, TTY: 212-821-9713, www.lighthouse.org • Low Vision Information Center , 301-951-4444, www.lowvisioninfo.org • The National Association for the Visually Handicapped, 800-677- 9965, www.navh.org • The National Federation of the Blind, 410-659-9314, www.nfb.org Adapting your Environment • Organize possessions and work space • Increase lighting levels • Heighten contrast • Avoid glare • Large print versions Conclusion .
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