Download CASE REPORT OUTLINE - American Academy of Optometry

CASE REPORT OUTLINE
Submitted by: Vivian Wong, OD, SCCO Pediatric Optometry/Vision Therapy Resident
A 45-year old female complains of photophobia, nyctalopia, and progressive and visual fields. Extensive
testing rules out ocular pathology and the patient is diagnosed with functional vision loss.
I. Case History
Patient demographics
- 46-years-old Caucasian female
Chief complaint
- Photophobia
- Nyctalopia
- Progressively worsening visual acuities OU
- Progressively worsening visual fields OU
Ocular History
- Photophobia and nyctalopia since 12 years of age
- Subnormal visual acuities throughout life
Medical History
- Bipolar syndrome
- Depression
- Attention deficit disorder
- Hearing impairment
- Migraine headaches
- Carpal tunnel syndrome
- Tennis elbow
- High cholesterol
Medications
- Epival, Seroquel, Clonazepam, Zoloft, and Ritalin for her psychiatric problems
- Crestor to control her high lipid levels
- Losec and Ditropan for her gastrointestinal and urinary issues
- Tylenol 3 and Celebrex to relieve her pain
- Reactin and Nasonex for seasonal allergies
- Advair and Ventolin puffers for asthma.
Other salient information
Family history
- Mother and maternal aunt could not drive at night due to glare issues but their vision was never tested.
- Eldest sister recently developed hearing and night vision problems
- Father and two sons are colour blind
- Youngest son was also photophobic and the “backs of his eyes are different-looking”
II. Pertinent findings
Visual Acuity
April 2007
OD 20/50
OS 20/40
April 2008
OD 20/100
OS 20/100
Refraction
Trial frame subjective refraction
August 2007
OD
+0.25/-0.75 x 059
OS
-0.50 DS
Visual Fields
The following are the field results obtained by Goldmann perimetry:
OD
OS
Patient showed severely constricted visual fields in both eyes that were about 5 degrees in diameter using
the V target size and 2 degrees in diameter using the III target size.
Electroretinogram
October 2007
Results indicated normal gross function of the outer 2/3rds of the retina. Flicker response was diminished
in both eyes due to blepharospasms during the flickering light stimulus.
Ocular Health
November 2007
Dilated fundus examination showed that no clinically detectable health changes in the retina were seen
Given the option of referral to a retinal specialist at that time for a possible fluorescein angiography.
However, she declined because it was of no functional benefit to her.
III. Differential diagnosis
Primary/leading
- Retinitis pigmentosa
Others
- Malingering
- Retrobulbar tumor
-Functional vision loss
IV. Diagnosis and discussion
- Diagnosis is functional vision loss (FVL)
- Prevalence
- Most prevalent in:
- Teenagers
- Mean age of 13.4 years11
- Females
- 3x more common than males11
- All socioeconomic groups are susceptible11
- Only 25% on public assistance
- Symptoms with no discernible pathologic etiology may account for 30-50% of patient
presentations for primary and secondary care22
- Affects 25 000 patients per year in the US21
- Occurrence in ophthalmic practices:
- 1-5% of patients3,7
- Definition
- Functional vision loss (FVL) is defined as a condition where the visual symptoms of the patient
do not correspond with any detectable pathology7,12,13
- Theories on functional vision loss etiologies
- Charcot8
Functional visual loss = form of hysteria
Hysteria was thought to be caused by a degenerative nervous system disease.
It dissociated mental functions and produced effects not mediated by functional
awareness
- Freud8
FVL is a product of psychological events
Internal conflicts lead to unconscious conversion of psychic energy into physical
symptoms
- Babinski8
Neither organic or psychological pathology causes FVL
Patients are merely “suggestible” i.e. they are easily influenced
Can be cured by persuasion
- Problems with diagnosis = misdiagnosis, ways to prevent
- Misdiagnosis rate = 2.2%11
- Algorithm to detect FVL8
- Financial impact
- Financial impact of FVL estimated at >$500US per patient spent on diagnosis3
- Psychosocial impact
>30% of patients reported underlying Stress, Anxiety, or Depression = SADness13
36.2% of people with FVL have a psychosocial association113
- Common symptoms in functional vision loss
- Decreased visual acuities in 26.1%13
- Usually <20/12011
- Usually symmetrical in both eyes11
- Abnormal visual fields in 28.3%13
- Constricted fields3,8
- Spiraling3,8
- Cross-over isopters3
- Focal defects3,8
- Other visual disturbances associated:11
- Photophobia
- Nystagmus
- Night vision loss
- Myopia
- Color vision
- Normal fundus in >50% of FVL patients11
**Symptoms found in case report patient
In this case, the patient presented with bilateral subnormal visual acuities ranging from 6/9 to
6/30 and bilateral constricted visual fields. She also complained of decreased night vision and
photophobia. All of these symptoms are consistent with the FVL symptomatic findings in
literature therefore supporting our diagnosis.
V. Treatment, management
Treatment and response to treatment
- Management of functional vision follows 3 steps:
1. Reassurance13
2. Realization13
3. Rehabilitation
- Efficacy of treatment based on reassurance
>2/3 of patients who received reassurance alone showed recovery from their visual dysfunction.8
- Prognosis of FVL
- Final outcome for FVL patients dependent on several factors:7
1. Accurate diagnosis
2. Patient’s willingness to acknowledge a problem and to seek help
3. Options available to help the patient
4. Proper management strategy applied corresponding to etiology
- Normalization in 58.3% of patients, especially children13
- Simple reassurance from physician, children can recover in 75 to 95% if cases8
- 45- 78% experience resolution of all visual symptoms3
**Patient managed as a true low vision case:
- Binoculars for distance
- Stand/Hand Magnifiers for near
- Photochromic lenses with high add bifocal
- Fresnel prisms to expand visual field
- Orientation and mobility training/Sighted guide dog
VI. Conclusion
1. When someone has vision loss that cannot be explained by ocular pathology, do not assume that
they are making it up! FUNCTIONAL VISION LOSS IS A REAL PROBLEM!
2. Focus on treating their SYMPTOMS to help them cope with life. KNOW WHAT’S
AVAILABLE!
3. Do not ignore possible ocular pathology that may precipitate later in the future
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