Full text of DOI:10.1038/eye.2000.201

KAREN E. BAIN, STEPHEN BEATTY,
CHRIS LLOYD
Non-organic visual loss
in children
Abstract
We report on the presenting features,
diagnosis, management and visual outcome of
30 patients, all under 16 years of age, with a
diagnosis of NOVL.
Background Patients with non-organic visual
loss (NOVL) can take up a disproportionate
amount of clinic time and clinicians often
resort to expensive and prolonged
investigations to ensure the correct diagnosis.
This is especially the case in children.
Methods The case notes of 30 children (18
girls, 12 boys) were retrospectively reviewed
following presentation with a primary
complaint of visual impairment and a
diagnosis of non-organic visual loss. This
figure represents 1% of new paediatric
referrals to our unit. Associated symptoms
included headache, periorbital pain, diplopia,
photopsia and photophobia. Visual field
defects were present in 5 patients and spasm
of the near reflex in 1 child.
Methods
This was a retrospective study of all patients
under 16 years of age diagnosed with functional
visual loss in the paediatric ophthalmology
clinics of one consultant (LCL.) in Manchester
Royal Eye Hospital between October 1995 and
June 1999. Included in this group were children
with coexisting ocular pathology but a
demonstrable functional overlay.
Non-organic visual loss was a clinical
diagnosis. Each patient underwent a thorough
orthoptic evaluation and a full ophthalmic
examination including fundoscopy. In cases
where reduced acuity was alleged but NOVL
suspected, an attempt to improve the vision
with well-established clinical tests, such as
neutralising lenses, was routinely made. This
was done by the orthoptist, prior to the
ophthalmic consultation. Where indicated,
further investigations were undertaken in the
form of electrophysiology, psychophysical
testing and neuro-imaging. Ultimately the
ophthalmologist proved to his or her
Results Treatment consisted of reassurance
and was associated with recovery of normal
visual function in all cases. Three children
were referred to other health care
professionals. All psychophysical,
electrophysiological and neuroradiological
investigations were negative.
Conclusion Our study shows that non-organic
visual loss is relatively common in pre-
pubertal children and that this condition can
be safely diagnosed using standard clinical
tests in the majority of cases. Prompt diagnosis
prevents unnecessary investigations and
prolonged 'disease' course. Coexisting social
conflict was common and may be a
satisfaction that the alleged symptoms could not
be attributed to demonstrable pathology.
contributory factor. Careful explanation and
reassurance to both the child and parents
remains the mainstay of management.
Results
Table 1 summarises the clinical findings at the
initial and final examinations. A total of 30
patients under 16 years of age were identified as
having functional visual loss. The age range was
6-15 years of age with a mean of 10 years. There
were 18 girls and 12 boys. Sources of referral
included optometrists (19, 63%), general
practitioners (3, 10%), other ophthalmologists
(4, 13%), paediatricians (2, 7%) and self-
presentation via casualty (2, 7%).
K.E. Bain
S. Beatty
C. Lloyd
Manchester Royal Eye
Key words Blindness, Functional, Hysteria,
Non-organic, Malingering
Hospital
Manchester, UK
Karen E. Bain �
Manchester Royal Eye
Hospital
Non-organic visual loss (NOVL) is a term used
to describe any disturbance of the afferent
visual system which cannot be attributed to
demonstrable pathology, in patients whose
symptoms can be circumvented using standard
clinical tests. It has been noted that NOVL is
particularly common during pre-pubertal
yearsl-3 and that social conflicts may play a role
among young patients.1ꢀ
Oxford Road
Twenty-eight patients (93%) complained of
reduced or blurred vision at presentation and
2 (7%) reported reduced acuity in conjunction
with other visual symptoms. Alleged acuity was
less than 6/60 in 3 cases (10%) and between
6/60 and 6/12 in 16 cases (53%). The visual
symptoms were bilateral in 25 cases (83%).
Manchester M13 9WH, UK
Tel: +44 (0)161 276 1234
e-mail:
k.e.bain@ukgateway.net
Received: 13 October 1999
Accepted in revised form:
21 March 2000
770
Eye (2000) 14, 770-772
©
2000 Royal College of Ophthalmologists

Table 1. Clinicalfindings at the initial and final examinations
Patient no.
Age (years)
Sex
Symptoms
Initial acuity
Fields
Final acuity
1
2
13
6
F
F
Blurred vision
6/18
6/12 L
Constricted
Not noted
Cloverleaf
Normal
6/5 R,6/5 L
6/6 R,6/6 L
6/6 R,6/6 L
6/5 R,6/5 L
6/6 R,6/6 L
6/6 R,6/5 L
6/6 R,6/6 L
6/5 R,6/5 L
6/6 R,6/6 L
6/4R,6/4L
6/6 R,PL L
6/6 R,6/6 L
6/5 R,6/4L
6/5 R,6/5 L
6/6 R,6/6 L
6/5 R,6/5 L
6/6 R,6/6 L
6/6 R,6/6 L
6/6 R,6/6 L
6/6 R,6/6 L
6/9 R,6/5 L
6/9 R,6/9 L
6/5 R,6/5 L
6/6 R,6/6 L
6/5 R,6/5 L
6/6 R,6/6 L
6/4R,6/4L
6/6 R,6/6 L
6/4R,6/4L
6/6 R,6/6 L
Blurred vision
6/24R,6/18 L
6/60 R,6/6 L
3
8
F
Blurring R eye
4
10
10
10
10
11
12
12
12
12
13
13
13
13
15
6
F
Blurred vision
6/18
6/18 L
5
Double vision
F
6/6 R,6/9 L
6/9 R,6/9 L
Not noted
Normal
6
Blurred vision
F
7
M
F
Optician found blurred vision
Blurred vision
6/18 R,6/12 L
6/5 R,6/5 L
6/36 R,6/60 L
6/9 R,HM L
6/18 R,PL L
6/24R,6/12 L
6/9 R,6/9 L
6/36 R,6/36 L
6/36 R,6/24L
6/9 R,6/9 L
6/18 R,6/18 L
6/6 R,6/6 L
2/60 R,6/5 L
Normal
8
Not noted
Constricted
Normal
9
M
F
Blurred vision
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Sudden blurring
Blurring R
M
M
M
F
Not noted
Normal
Variable vision
Blurred vision
Constricted
Normal
Blurred vision
M
M
F
Blurred vision
Normal
Failed school VA test
Blurred vision
Not noted
Normal
M
F
F
Sudden blurring
Sudden blurring
Blurred vision
Normal
6
Not
7
6/18
Not noted
Not noted
Not noted
Normal
6/18 L
8
M
F
OptiCian found reduced vision
Blurred vision
6/12 R,6/9 L
6/18 R,6/18 L
6/36 R,6/24L
8
8
F
Blurred vision
9
F
Blurred vision
6/36
6/36 L
Not noted
Normal
9
M
M
F
Convergent squint
Difficulty at close work
Blurred vision
6/9 R,6/12 L
6/18 R,6/6 L
9
Normal
9
6/24
6/18
L
Normal
9
F
Blurred vision
6/12 R,6/12 L
6/18 R,6/12 L
6/9 R,6/9 L
Not
15
8
F
Blurred vision
Blurred for blackboard
Constricted
Normal
M
Five patients (17%) complained of field loss in
association with reduced acuity, but none reported field
defects in the presence of normal central vision. Patterns
of field loss included concentric constriction (4) and
cloverleaf-shaped fields (1).
department, which confirmed the presence of a temporal
lobe space-occupying lesion. This diagnosis had been
made and the lesion surgically excised prior to the onset
of NOVL.
Ocular co-morbidity was uncommon among our
patients and was seen in only 5 cases (17%). Coexisting
ocular disease included refractive error (3, 10%), corneal
scarring secondary to herpes simplex keratitis with
associated amblyopia (1, 3%) and nystagmus secondary
to temporal lobe pathology (1, 3%).
Other symptoms included diplopia or polyopia (5,
17%), photopsia (1), photophobia (1), alteration of colour
vision (1) and difficulty with reading (1). The most
common associated complaint was headache, in 13 cases
(43%).
The duration of alleged symptoms at the time of
presentation ranged from 1 day to 3 years (mean 7
months). Referral letters mentioned the following specific
diagnoses in 13 cases: optic nerve disease or trauma (4),
retinal disease (1), uncorrected refractive error (2),
orthoptic disorder (5) and cerebral pathology (1).
Twenty-one patients (70%) were shown to have 6/6 or
better vision at the first clinic appointment using
techniques such as neutralising lenses (15 cases, 50%) or
encouragement, bribery with sweets, and time (5, 17%).
Twenty-seven (90%) had normal stereoacuity at the first
visit. Five patients had physiologically inconsistent
visual fields. Two patients reported spontaneous
improvement of vision at clinic and demonstrated 6/6
acuity without the use of subterfuge.
The treatment offered to all patients consisted of
careful explanation and reassurance. The diagnosis was
discussed with parents alone, and again with the
children present. In all cases the excellent prognosis was
emphasised.
Eighteen children (60%) were diagnosed at the first
visit and were not reviewed. Eight had recovered full
visual function by a second appointment and were
discharged. Four were seen a third time.
At final follow-up all patients
an acuity of 6/9 or
better in both eyes, except for one child with unilateral
reduced acuity secondary to corneal scarring. Only one
patient reported persistence of her symptoms at review.
Three cases were referred to another health care
professional: a psychiatrist, a neurologist for persistent
headaches and an educational psychologist.
Six patients (20%) underwent investigations in the
form of electrophysiology (4), colour vision assessment
(5) and neuro-imaging (4). Three of these patients had
undergone neuro-imaging prior to referral to our clinic.
All these investigations were reported as normal with the
exception of one MRI scan, performed in the referring
Eighteen of our patients (60%) admitted to concurrent
social problems, either at home or in the school.
Impending exams,
recent change of school and
difficulties with schoolwork were cited as possible
causative factors by the patients or their parents. Parental
771

visual impairment more difficult, coexisting pathology in
cases of NOVL is well described?ꢁ A functional
element should therefore always be considered when the
level of a subjective response is inconsistent with the
established pathology.
separation or divorce and subsequent changes of family
composition were mentioned in 5 cases (17%). One child
had stayed with several different foster families over a
period of 6 months. In none of our patients was sexual or
physical abuse suspected. Four children (13%) had
relatives or friends with spectacle correction or had
expressed a desire to wear glasses prior to developing
the alleged visual impairment.
Sixty per cent of our patients, or their parents,
acknowledged difficulties in the home or school at the
time of clinic attendance. This compares with 40% in the
study by Catalano et al.l and 90% in Keltner's study.4 It is
possible that sources of conflict in some children may go
unrecognised. The difficult home circumstances
experienced by one child in our group were not obvious
until he was questioned in more detail by a child
psychologist. However, it is worth noting that Kathol
et al.lO found psychiatric consultation in cases of NOVL
did not affect the eventual visual outcome. Our study
shows there is usually full resolution of symptoms with
reassurance alone - findings consistent with other
studies.I•2•6
Discussion
Our series of 30 children shows a gender bias with a
female to male ratio of 1.5:1 and a cluster in the 8-13 year
age groupl-4 which concurs with previous studies. The
level of alleged visual loss was moderate (6/12 to 6/36),
and bilateral visual involvement was reported in the vast
majority (83%). This is also consistent with previous
work.l-4 Sixty-three per cent of our cases were referred
by their optometrist, in contrast to 12% of our new
paediatric referrals in a standard calendar month. This
reflects the prominent role of the optometrist in initial
care of a child with blurred vision, and the high rate of
secondary as well as tertiary referrals within our
hospital.
NOVL is a relatively common problem in children,
especially in the 8-13 year age group, and predominantly
affects girls. NOVL can present with a plethora of visual
symptoms and the ophthalmologist should therefore be
vigilant to the possibility of this diagnosis. However, it
should be emphasised that every child with a visual
complaint must be presumed to have ocular patholoꢂ
until proven otherwise. Functional visual impairment is
easily demonstrable in the majority of paediatric cases
using simple clinical techniques. Prompt diagnosis will
prevent unnecessary investigations and follow-up, and
will also contribute to a more rapid resolution of the
child's symptoms. In children, the visual prognosis of
NOVL is usually excellent.
The majority of our patients were shown to have 6/6
acuity or normal stereoacuity at the first visit. As a
comprehensive orthoptic assessment, including use of
neutralising lenses, is done routinely for any patient
suspected of having functional visual impairment, the
diagnosis of NOVL is made promptly without resorting
to unnecessary investigations. The patient and parents
can therefore often be reassured on the first paediatric
clinic visit, avoiding prolongation of symptoms. All
patients subsequently experienced full recovery of
normal acuity and resolution of symptoms. None of these
patients have, to our knowledge, had recurrent episodes
of NOVL.
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