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Visual Dysfunction in Chronic Fatigue Syndrome
By Lesley J. Vedelago, O.D.

                                      CFIDS Association of America
                        Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS)

There are few references in the literature to                     Misjudging distances, clumsiness, poor
visual and/or ocular disturbances in chronic                       balance and coordination. Difficulty driving
fatigue syndrome (CFS), even though visual                         due to problems judging distances;
symptoms are common. Ocular symptoms have
                                                                  Dizziness and inability to tolerate looking
been quantified, and are significantly more
                                                                   at moving objects;
common than in control groups.1
                                                                  Spots, flashes of light, floaters and halos;
The ocular signs and symptoms of CFS have
not been considered to be a major part of this                    Intolerance to light (glare);
condition in the past, yet it becomes very
                                                                  Grittiness, burning, dryness or itchiness.
obvious when working with these patients that
the ocular system is very much affected by,                        Patients complain of sore eyes usually
and in turn affects, this systemic condition.                      becoming worse as the day progresses;

Symptom histories of 141 CFS patients                             Headaches often increasing when reading,
referred to my practice are summarized in                          concentrating visually and driving.
the accompanying table. The majority had                         In many cases almost all of these symptoms occur,
complained to the referring doctor of                            producing varying degrees of disability. These patients
bothersome visual complaints, but some                           have sensory intolerance and appear to have a degree
had not considered their visual problems                         of inability to suppress background sensory events
to be significantly affecting their day-to-day                   from reaching a distracting level in consciousness.
function, or may not have mentioned any
visual problems at all.                                          Objective Ocular Findings
                                                                 Upon examination, findings may include:
Visual symptoms
The visual symptoms typically encountered                         Poor oculomotor control. This is evident when
with CFS patients include:                                         observing motilities, particularly saccadic eye
                                                                   movements. Saccades, normally quick eye
 Blurred or foggy distance and/or near vision.                    movements, are very slow, with marked jerkiness.
   Blur tends to fluctuate according                               Conscious effort goes into changing visual
   to the state of the fatigue at the time;                        fixation, as if it is hard to let go of looking at an
 Difficulty focusing from distance to near                        object once vision is fixed on it. Pursuits (tracking
   and/or near to distance;                                        an object) are not smooth and cannot be done
                                                                   quickly. Discomfort and often nausea is
 Slowness or inability to focus on objects,                       associated with saccadic and pursuit eye
   particularly at near;                                           movements;
 Difficulty tracking lines of print. Patients seem               Exophoria, the tendency for one eye to diverge
   confused and distracted by the lines of print                   or turn outward when the other eye is covered,
   above and below where they are reading;                         is often greater at near in these patients, usually
 Poor short-term memory and concentration                         with a slow recovery. However, the exophoria
   (generally) with reading being markedly                         may not appear high due to a long-term
   affected;                                                       compensation process. CFS patients often adopt
                                                                   a typical posture associated with exophoria-sitting
 Diplopia or ghosting of images;                                  well forward on the chair with their shoulders
 Problems with peripheral vision; patients                        halfway down the chair back in a semi-reclined
   complain of not seeing objects in their side                    position;
   vision and of continually bumping into things                  Remote nearpoint of convergence, where both
   and veering. Some say they feel like they                       eyes converge on the same close-in location at
   have tunnel vision;                                             the same time, is usually observed, with slow
                                                                   recovery. This test may be quite painful;

                  (Worcestershire M.E. Support Group’s Library) 41650bcc-fd7e-4ade-b241-b62a85d76135.doc
April 2005                                         Page 1 of 3                                             Issue 1.0
Visual Dysfunction in Chronic Fatigue Syndrome
By Lesley J. Vedelago, O.D.

 Reach/grasp/release tests that require the                       Patients generally report things look brighter,
   patient to reach out and touch or grasp an                      they can see more, concentrate better, and
   object, shows a marked decrease in the                          neck pain and tension, including headaches,
   patient’s ability to reach and grasp after                      have been relieved. They often say the foggy
   release. One eye usually diverges without                       or cloudy feeling in their head has gone and that
   the patient being aware. Patients often                         they can read for longer periods. Yoked prisms,
   complain of nausea, significant discomfort                      where the base ends of the prisms are placed in
   or dizziness when performing this test;                         the same position for each eye, can also produce
                                                                   dramatic changes in some patients.
 Near/far/near fixations commonly show poor
   convergence at near with one eye usually                       Progressive lenses are my choice for CFS
   diverging. Such vergence changes are                            patients. I use them as supportive lenses to
   typically very slow and often uncomfortable                     reduce the effort of focusing from distance to
   to execute, with sometimes an associated                        near, providing progressive clear vision.
   tendency to use raised eyebrows and wide
                                                                  Tints are regularly used because of the
   open eyes to assist in changing to far;
                                                                   increased sensitivity to light.
 Constricted peripheral fields. In my experience,
                                                                  Ocular lubrication therapy is often needed
   treatment with lenses and vision therapy
                                                                   to treat the dry eye problem and symptoms,
   produces marked improvements in field.
                                                                   and to eliminate the corneal staining. Warm
   In my opinion there are probably several factors
                                                                   compresses may also provide some relief.
   involved, including improved central/peripheral
                                                                   Many of these patients have significant allergy
   processing and sensory-motor coordination,
                                                                   problems and I will also proffer advice on relief
   and hence heightened attention;
                                                                   of allergic symptoms.
 Staring appearance; low blink rate and
                                                                 I find it interesting that in patients with fibromyalgia,
   incomplete blinking;
                                                                 a significant portion have a history of one or more of
 Small pupils;                                                  the following: strabismus, amblyopia, anisometropia,
                                                                 eye surgery for strabismus (often multiple), long-
 Sensitivity to lights;
                                                                 standing binocular vision problems, nystagmus,
 Tear film and ocular surface abnormalities.                    whiplash or closed head injury. All of these
   Low tear break-up time, related to inadequate                 conditions have significant potential effects on body
   production of the oil or mucus layer in tears,                posture. The long-term effects of poor body posture
   is frequently observed. So is rose bengal                     on the overall health of the individual have been well
   corneal staining, which reveals cell death                    documented, and visual dysfunctions appear to be a
   in the cornea due to dryness;                                 major contributing factor to poor body posture in CFS
 Low grade chronic allergic conjunctivitis;
                                                                 Because CFS is a real illness of increasing
 Visual midline shift in these patients,                        prevalence, and as fatigue itself becomes better
   particularly if the patient has been diagnosed                understood, it is important that eye specialists are
   with fibromyalgia.                                            not only fully informed about the condition itself, but
                                                                 also cognizant of the ocular/visual disturbances for
Management of the CFS patient                                    which we can play an important role in treatment
Behavioral optometric management of the                          and rehabilitation.
visual manifestations of CFS should utilize the
following treatment options:                                     Reference
 Best subjective correction for distance and                    Potaznic W et al. Ocular manifestations of chronic
                                                                 fatigue syndrome and immune dysfunction syndrome.
   near. Patients respond favorably to low plus
                                                                 Optom Vis Sci. 1992; 69:811-814.
   lenses at near.
                                                                 Lesley Vedelago is a fellow of the Australasian
 Prisms ground into prescription lenses.                        College of Behavioural Optometrists and the College
   Base-in prisms, where the thickest part is                    of Vision and Development, and a member of the
   placed nearest to the nose, often provides                    Neuro-optometric Rehabilitation Association. She
   immediate relief. This is particularly true for               runs a behavioral optometric practice in Brisbane,
   near vision, but base-in prisms can also                      Australia, and is an associate lecturer at the
   greatly reduce the severity of visuo-spatial                  University of New South Wales.
   symptoms, sometimes completely.

                  (Worcestershire M.E. Support Group’s Library) 41650bcc-fd7e-4ade-b241-b62a85d76135.doc
April 2005                                         Page 2 of 3                                              Issue 1.0
Visual Dysfunction in Chronic Fatigue Syndrome
By Lesley J. Vedelago, O.D.

Excerpted with permission from Visual Dysfunction in                         Ambient visual nerve fibers from the peripheral
Chronic Fatigue Syndrome: Behavioural Optometric                             retina are relayed to the midbrain, where they
Assessment and Management.                                                   become part of the sensory-motor feedback loop.
Journal of Behavioral Optometry. 1997; 8(6):149-153.                         Even when the eye is fixed on an object in the
Text has been edited for clarity.                                            visual field, the ambient process is feeding
                                                                             information from the peripheral vision to the
Prevalence of Symptoms in 141 CFS Patients                                   brain to help it make sense of what it sees.
Poor concentration ................................           78.7%          When the ambient visual system is damaged,
Near blur ................................................    65.9%          patients' peripheral vision no longer helps them
Visuo-spatial balance/coordination .......                    62.2%          stabilize and orient images in the same way, and
Poor memory .........................................         59.6%          they have to rely more heavily on their focal
Headache ..............................................       55.8%          processing system. The focal processing system
Photophobia ..........................................        53.9%          uses only the macular area of the retina instead
                                                                             of the peripheral nerves. It feeds information to
Distance blur..........................................       44.7%          the brain about an object only if the eye is fixed
Near/far/near blur ..................................         39.7%          directly on it.
Dizziness/difficulty with moving objects                      38.3%
Sore eyes ..............................................      35.5%          Dr. Padula has named this condition post-
                                                                             traumatic vision syndrome (PTVS). Typical
Stopped work.........................................         31.9%
                                                                             symptoms of PTVS include intermittent blurry
Neck pain ...............................................     26.9%          vision, perceived movement of print or stationary
Spots/floaters/halos/flashes ..................               20.6%          objects, headaches, light sensitivity and seeing
Stopped driving......................................         12.6%          words and print run together.
Diplopia ..................................................   9.9%
                                                                             "I have treated many patients with CFS who suffer
                                                                             from PTVS," Padula says. "The imbalance in their
The role of visual processing systems                                        visual processing systems slows everything down
                                                                             and causes them to focus on a single object in the
Clinicians often send CFS patients who
                                                                             visual field at a time. They have difficulty
report vision problems to an optometrist or
                                                                             re-focusing, tracking objects or isolating details."
ophthalmologist for evaluation. But the
specialists frequently find no abnormalities                                 He believes that some CFS patients may also
in the structure of the eyes, and treatment                                  suffer from visual midline shift syndrome (VMSS).
reaches an impasse.                                                          In VMSS, a neurological event interferes with
In these cases, the source of the problem may                                vision processing from only one side of the body.
lie in the brain and not the eyes themselves,                                The ambient process attempts to create a relative
according to William Padula, OD, neuro-                                      balance in the visual field by expanding its
optometrist and head of the Padula Institute of                              concept of space on one side of the body
Vision Rehabilitation in Guildford, Conn.                                    compared to the other. This results in a shift in
"Persons with CFS have in essence suffered a                                 the individual's perception of where the midline
neurological event that affects their vision similar                         of vision is, usually away from the affected side.
to traumatic brain injury or multiple sclerosis,                             Individuals with VMSS often have poor posture
although that is not widely recognized by                                    and balance, and tend to lean to one side or the
medical practitioners," Padula says.                                         other. Dr Padula reports that most of his CFS
Padula believes CFS patients may have                                        patients suffer from anterior/posterior VMSS,
dysfunction in the part of their brain that controls                         tending to lean forward or backward instead of
the ambient visual process, which lets us know                               right or left. This may lead to neck, back, and
where we are in space and provides information                               shoulder pain.
used for balance, coordination and posture.                                  From:

                       (Worcestershire M.E. Support Group’s Library) 41650bcc-fd7e-4ade-b241-b62a85d76135.doc
April 2005                                                     Page 3 of 3                                            Issue 1.0

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