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Letters to the Editor

ICP or cryptococcal brainstem vasculitis.
It may be that antifungal regimen was
inadequate and control of ICP is vital.
However, in our case it was difficult
to justify the transfer to neurosurgical
ICU, as there were clear signs of
improvement.
At the same time this case illustrates
dramatic and sometimes fatal course of
cryptococcal meningitis as presenting
feature in AIDS. Patient’s GCS deterior-

ated without any preceding cardiorespiratory event, seizures or prolonged
duration of loss of airway with risk of
aspiration. Clinically, terminal event suggests catastrophic brain stem pathology
which could either be due to raised ICP or
cryptococcal vasculitis [2]. Unfortunately
autopsy was not performed.

References

Drawing double images: a case of
anosognosia for diplopia

and never admitted his errors, even upon
repeated confutation. However, during
the clinical interview the patient spontaneously stated that he was in the hospital
because of paresis on his left side, due to a
cerebrovascular accident.
At that time, a neuropsychological
assessment showed moderate left extrapersonal neglect (3/21 left-sided omissions
on a line cancellation and 36/54 on a star
cancellation task; 14 mm mean rightward
displacement on 20-cm horizontal line
bisection), without defects of verbal shortterm memory and learning (word and digit
span, Rey’s 15-word test, story recall test),
or of abstract thinking (abstract verbal
reasoning test, cognitive estimation test),
in reference to Italian age- and educationadjusted normative data. On copying
drawings the patient often omitted leftsided elements, and showed a systematic
tendency to draw figures or their elements
twice. An extended copying task under
binocular or monocular viewing (30 geometrical drawings per condition) demonstrated consistent Ôdouble drawingÕ in the
binocular viewing condition only, in both
visual hemifields (Fig. 2). The patient
always judged his performance as adequate; when he was shown his own wrong
reproductions together with the respective
models under monocular viewing, he
provided vague or confabulatory explanations of his mistakes (e.g. Ôthis was not
the modelÕ, or Ôwhen I’m tired, I often am
in straitsÕ), in a fashion similar to that
described in patients affected by anosognosia for cortical blindness (Anton’s syndrome).
Diplopic subjects perceive each visual
stimulus doubled, but they usually
acknowledge that one is a ÔfalseÕ image
and can depict it under request [1,3]. Our
patient showed spontaneous ÔduplicatedÕ
drawing, a finding not reported so far.
This behaviour was abolished by left or

right eye patching, allowing us to exclude
other positive pathologies of vision [4] and
neglect-related perseverations [5]. Therefore, Ôdouble drawingÕ could be ascribed to
anosognosia for binocular diplopia. Such
a defect would explain the lack of selfreport of diplopia in right-damaged patients with cortical squint [1].
In our patient unawareness for diplopia
was not related to a general intellectual
impairment or to affective/motivational
denial, as the patient did not deny his
disabling left motor defect. A disorder at
higher levels of visual processing [6], and,
more specifically, a defect in conscious
processing of visual information (firstorder explanation; see Ref. [7]) could
better explain the present findings. We
could also speculate that the right temporo-parietal lesion made our patient
unable to comprehend his defective processing of binocular information. Functional neuroimaging studies demonstrate
that a wide neural network, including
regions outside the visual cortex, contribute to the conscious visual experience
[8,9]. The present findings would support
the role of non-visual cortex in awareness
of visual impairments.

M. Leporea, M. Consonb, D. Grossib and
L. Trojanob
a

Stazione Climatica Bianchi, Portici; and
Department of Psychology, Second University of Naples, Caserta, Italy
b

Correspondence: Luigi Trojano, Department of Psychology, Second University of
Naples, Via Vivaldi 43, 81100 Caserta,
Italy (tel./fax: +39 0823 274774; e-mail:
luigi.trojano@unina2.it).
Keywords: diplopia, drawing, visual
awareness, visual neglect
Received 22 September 2004
Accepted 16 January 2005
Sir,
Squint and diplopia usually follow brainstem damage, but have been rarely reported after purely cortical lesions [1].
Diagnosis of diplopia mainly rests on
subjective reports: virtually all patients
criticize their deficit [2]. We report for the
first time a patient with left neglect and
binocular diplopia who was not aware of
his visual defect.
A 76-year-old right-handed lawyer
presented an haemorrhagic stroke in the
right middle and superior temporal gyri
and in the posterior parietal lobule
(Fig. 1). On admission in a rehabilitation
unit, 1 month after stroke, the patient
showed left hemiparesis and hemianaesthesia, without visual field loss as assessed
by Goldmann perimetry. Standard orthoptic measures demonstrated corrected-tonormal visual acuity, no limitations of
ocular movements, binocular diplopia,
and divergent squint on the Cover test. In
ecological settings the patient sometimes
asked for ÔduplicatedÕ objects close to him

1. Angstwurm K, Sokolowska-Koehler W,
Stadelmann C, Schielke E, Weber JR. Fulminant cryptococcal meningitis as presenting feature in a patient with AIDS. European
Journal of Neurology 2004; 11: 353–354.
2. Lan SH, Chang WN, Lu CH, Lui CC, Chang
HW. Cerebral infarction in chronic meningitis: a comparison of tuberculous meningitis
and cryptococcal meningitis. The Quarterly
Journal of Medicine 2001; 94: 247–253.

References
1. Flower MS, Wade DT, Richardson AJ,
Stein JF. Squints and diplopia seen after
brain damage. Journal of Neurology 1996;
243: 86–90.
2. Lee MS, Volpe NJ. Double vision. Curr
Treat Options Neurol 2001; 3: 383–388.
3. Jones MR, Waggoner R, Hoyt WF Cerebral
polyopia with extrastriate quadrantanopia:
report of a case with magnetic resonance
documentation of V2/V3 cortical infarction.
Journal of Neuro-Ophthalmology 1999; 19:
1–6.
4. Ffytche DH, Howard RJ. The perceptual
consequences of visual loss: ÔpositiveÕ pathologies of vision. Brain 1999; 122: 1247–
1260.

Ó 2006 EFNS European Journal of Neurology 13, 201–208

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207

Figure 1 CT-images showing the patient’s hemorrhagic lesion involving the right middle and superior temporal gyri and the posterior
parietal lobule.

Figure 2 Patient’s graphic productions on the extended copying task: in the binocular viewing condition (a) the patient always drew figures
or their elements twice, sometimes side by side or one above the other, sometimes partially overlapping them; in monocular left (b) or right
(c) viewing conditions he performed flawlessly.

Ó 2006 EFNS European Journal of Neurology 13, 201–208

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Letters to the Editor

5. Rusconi M, Maravita A, Bottini G, Vallar
G. Is the intact side really intact? Perseverative responses in patients with unilateral
neglect: a productive manifestation. Neuropsychologia 2002; 40: 594–604.
6. Bisiach E, Vallar G, Perani D, Papagno C,
Berti A. Unawareness of disease following
lesions of the right hemisphere: anosognosia
for hemiplegia and anosognosia for hemianopia. Neuropsychologia 1986; 24: 471–482.

7. Schacter DL. Toward a cognitive neuropsychology of awareness: implicit knowledge and anosognosia. Journal of Clinical
and Experimental Neuropsychology 1990; 12:
155–178.
8. Rees G. Neuroimaging of visual awareness
in patients and normal subjects. Current
Opinion in Neurobiology 2001; 11: 150–156.

9. Vuilleumier P, Sagiv N, Hazeltine E, et al.
Neural fate of seen and unseen faces in
visuospatial neglect: a combined eventrelated MRI and event-related potential
study. Proc Natl Acad Sci USA 2001; 98:
3495–3500.

Ó 2006 EFNS European Journal of Neurology 13, 201–208