Functional Vision Loss: A Case Presentation
B.C., an eleven-year-old female presented with decreased DVA, manifested as the inability to read the chalkboard at school. Her extracurricular activities include skating and swimming, and she has no visual complaints when participating in these sports. She reports that her near vision is good and she can read for hours without difficulty. She has never had an eye exam, and has never worn glasses. Her ocular health history, as well as her family health history (both ocular and systemic), are unremarkable per her father.
Entering acuities 20/50
20/60
DCT 1XP
NCT ortho
NPA 16.67D
NPC 5cm
Stereo 40"
Butterfly
Versions SAFE
Pupils PERRLA
K's 43.50/44.75
43.75/44.50
Ret. -0.25
DS
-0.25 DS
Monoc. Subj. -0.25 DS 20/15-
-0.75 DS 20/15-
VG Balance -0.25 DS 20/15-
-0.50 DS 20/15- 20/15
OU
During retinoscopy, I was talking to the patient about her family. She mentioned that her parents were getting divorced and she was moving to Nevada to live with her grandmother and aunt. During the refraction I had the feeling that the patient was intentionally missing letters. When I saw that her RE did not agree with her entering VA's, I took her out of the phoropter, placed her "prescription" (-0.12D OU) into a trial lens holder and asked her if she was able to read the 20/20 line. She easily read 20/20 with this prescription.
When I attempted to proceed with a slit lamp exam the patient could not tolerate the light even at the smallest and dimmest setting. The patient stated that it "hurt her eyes too much". She would not allow me to put any drops in her eyes. Finger tensions were firm and equal. The small amount of SLE and non-contact that was done revealed clear lids, lashes, conjunctiva and cornea, with a .3 C/D ratio, distinct margins, and a flat/even macula. Small pupil BIO was not completed due to photophobia. FDT was full OU.
After explaining the exam findings to the father without the patient present, I recommended to the patient that she wear sunglasses outdoors as often as possible to protect her eyes and help her vision.
How would you classify this patient's disorder??
Psychosomatic Disorder Classifications
Somatoform Disorders
Unconsciously determined symptoms with
no physiological cause; may be in response to current stressors or past traumas;
in most cases, symptoms regress with constant, long term reassurance
Types: Somatization disorder not otherwise
specified
Adjustment disorder with physical symptoms
Grief Reaction
Undifferentiated Somatoform Disorder
Somatization Disorder
Hypochondriasis Conversion Disorders (aka: hysterical neuroses)
Pain
Disorder
Body Dysmorphic Disorder
Factitious Disorders
Consciously exaggerated, feigned, or self-induced
symptoms with potential social ramifications for the patient; these are under
the patient's voluntary control and may involve the fabrication of symptoms
or the intentional use of irritants
Types: Malingering
Munchausen's Syndrome
Stress Related Physiological Responses
Unconscious, involuntary change in patient's
physical state secondary to stress or psychological factors
Noncompliance
Physical symptoms due to the conscious
or unconscious denial of illness and refusal for treatment
*Please see the attached tables for more information
on the above disorders
How to Approach These Patients During the
Examination
These patients must be handled with patience
and empathy; there may be deep-rooted psychological pain at the heart of the
disorder (and I think very few of us are prepared for our patient to come
unglued in our exam room!). In addition, it is helpful in your diagnosis to
note whether the formation of such symptoms is conscious or unconscious, whether
there are current external stressors that coincide with the physical symptoms,
and whether or not the patient is uncomfortable with or wishing to be in the
sick role.
Going back to Dar Fong's 100C lecture
on Functional Vision Loss (10/5/99), she recommended that we complete a comprehensive
exam to the best or our abilities with lots of encouragement and thorough
documentation of the findings. Remember to observe the patient's mannerisms
and take a good, detailed case history. The most common complaints will be
decreased VAS or loss of the visual field. When measuring acuity, try isolating
rows or letters or using your pinhole occluder. Tangent screen visual fields
are the most effective in diagnosing functional vision loss because they can
be altered (unlike the automated ones), such as changing test distances, etc.
If you suspect that you have a
malingerer remember that you can use the following techniques to trap the
patient:
· Changing VA test distance
· Use Red/Green glasses or Red/Green slide (trap the bad eye with letters
in red ink)
· Rotating Cylinder
· High Plus Reading Add
· Prolonged Refraction
· Potential Acuity Meter
· BV tests (stereo, 4 BO test)
· Ishi #12 plate
Functional Vision Loss is a diagnosis of exclusion or entrapment.The treatment and management of these patients is left up to the discretion of the individual doctors' philosophies. In general, the best approach is usually reassurance that the eyes are healthy. If you do not wish to confront your patient on the issue, offer to see them again in a few months to confirm that their eyes are healthy (most malingerers will never return, and some hysterics may be over their psychological affliction within that time). It is generally agreed upon NOT to prescribe something just to please the patient; placebos don't get at the heart of what's going on.
For More Information
Dar Fong's 100C Lecture. Functional Vision Loss. October 5, 199.
Nason, FE. Somatic Preoccupations, Factitious Illness, and Noncompliance.
Principles and Practice of Ophthalmology.
Albert and Jakobiec, Eds. Second edition. Volume 6. "Mind versus body, health
versus disease, wellness versus sickness, and psychogenic versus organic are
the relevant dichotomies here."