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Congenital Mydriasis, Failure of Accommodation, and Patent Ductus Arteriosus
Arch Ophthalmol. 2002;120:509-510.
Congenital mydriasis is a very rare abnormality that occurs in combination
with a failure of accommodation. Herein we describe 2 patients in whom these
ocular defects are associated with patent ductus arteriosus (PDA).
Report of Cases
Case 1
This 15-week-old infant was first seen by us 2 weeks after she had undergone
surgery for a large PDA.1 Her parents had
observed the dilated pupils since birth. The photographically measured diameter
of the round pupils was 6.5 mm. They were not reactive to light, to an eyelid
closure effort, or to the administration of up to a 1% concentration of pilocarpine
eyedrops. Streak retinoscopy revealed a refraction of OD +3.0 diopter sphere
(D sph) and OS +2.5 D sph that remained uninfluenced by topical application
of pilocarpine. Apart from the lack of accommodation and pupillary constriction,
all ocular findings were normal. No other pupillary abnormalities were known
in the family. The infant was given spectacles to wear for focusing at close
distance. Within the following 2 years, a tortuosity of the retinal arteries
with several loops near the optic disc became apparent. Having now observed
the girl for 9 years, the tortuosity has increased while the pupils have not
become smaller (diameter, OU 6.78 mm). They did not dilate after administration
of up to a 5% concentration of phenylephrine eyedrops. The iris stroma is
hypotrophic, without crypts. Diaphanoscopy of the iris did not reveal an absence
of the posterior pigmented iris epithelium nor was there any abnormal finding
in the sphincter zone. The axial bulbus length is now OD 19.77 mm and OS 20.03
mm. Meanwhile, the refraction of +7.75 D sph combined with –1.0 cylinder
x 171° OD and +7.25 D sph combined with –1.5 cyl x 172°
OS is corrected by multifocal glasses. The visual acuity is 0.8 OD and 1.0
OS. The mental development of the girl is normal. Her length and body weight
are near the third percentile.
Case 2
This prematurely born infant (at 34 weeks' gestation; weight, 1940 g)
had been operated on for a large PDA at the age of 2 weeks. The diameter of
her pupils was 7 mm without change either to light or to the administration
of up to a 1 % concentration of pilocarpine eyedrops. There was also no dilatation
after administration of a 5% concentration of phenylephrine eyedrops (photographic
measurements). The examination with a handheld slitlamp revealed a persisting
pupillary membrane (a grid of filiform tissue originating midstroma and reaching
across the pupil). The iris stroma was hypotrophic, without crypts. Diaphanoscopy
showed some small defects of the pigment epithelial layer at the 8- to 9-o'clock
position of the left iris periphery. The lens was in its regular position.
Indirect binocular ophthalmoscopy showed poor pigmentation of the fundus and
a slight tortuosity of the retinal arteries. Streak retinoscopy revealed a
refraction of OD +3.0 D sph and OS +2.5 D sph that did not change after application
of 1% pilocarpine eyedrops. There was no known family history of other pupillary
abnormalities. We prescribed a spectacle correction focusing at arm's length
and have kept the infant under observation.
Comment
The first 2 reported cases of bilateral congenital mydriasis occurred
in monozygotic twins.2 More females than
males are affected, typically bilaterally.1-4
Unilateral congenital mydriasis was described,5
once in a male patient with Waardenburg syndrome.6
In hereditary cases, an autosomal dominant mode of inheritance and an X-linked
mode with nonviability of males were discussed.2, 4
The pathophysiologic correlate of congenital mydriasis and lack of accommodation
is not unequivocal so far. A complete lack of cholinergic sensibility of the
iris sphincter and the ciliary muscle can be discussed. If complete agenesis
of the parasympathetically innervated muscles were the cause, diaphanoscopy
of the iris should have revealed an absence of the iris sphincter muscle,
but there was only peripheral spotty loss of the posterior pigmented iris
epithelium in 1 eye of our patient 2. In case of (acquired) neurogenic origin,
cholinergic supersensitivity should be expected, but all the reported cases
of congenital mydriasis showed either no or only poor reaction to pilocarpine.
In one patient, a 4% pilocarpine solution constricted the pupil a little and
a 10% phenylephrine solution led to a rapid dilatation, suggesting the presence
of an iris sphincter and dilator muscle.4
In our 2 cases an (congenital) aplasia of the small cells of the oculomotor
complex is imaginable, leading to an "orthograde transsynaptic dysgenesis"
of the corresponding muscles (the same mechanism can be imagined if a lack
of sensibility of the cholinergic receptors was the cause), thus also explaining
the lack of a response to pilocarpine. The lack of response to phenylephrine
might be explained by fibrosis of the sphincter muscle tissue. Alternatively,
a dysgenesis involving all the intraocular muscles can be discussed. Ataxia
and oligophrenia are excluded in our case 1, and so far case 2 also reveals
no findings pointing to Gillespie syndrome.7-8
An involvement of the ciliary muscle was recently mentioned in a case
of congenital mydriasis.3 In most patients
whose cases are reported in the literature, it cannot be excluded because
of their old age.2, 4, 6
The history of one woman whose presbyopic symptoms had not appeared until
she was 45 years old is only anecdotal.4
Regarding visual function, mydriasis may cause some glare and contribute to
the blur of the retinal image, but the lack of accommodation is the decisive
defect. To prevent amblyopia, correction of the refractive error is indicated
with focusing at arm's length (if accommodation is impossible) in infancy,
and from 6 months onward with the use of bifocal glasses focusing at arm's
length and 1 m, and later by multifocal glasses. In addition, sunglasses are
sensible.
Congenital mydriasis is an extremely rare condition, and the incidence
of extreme PDA is low. Of 15 reports—several of which are based only
on history and are not thorough—there are 3 well-documented cases that
bear testimony to an association between bilateral congenital mydriasis, insufficiency
of accommodation, and PDA. Such an association can therefore hardly be explained
by pure chance. As a fundamental pathophysiologic mechanism, a receptor defect
of the smooth muscles of both the eye and the media of the ductus arteriosus
can be hypothesized. Further investigation will be necessary to elucidate
the frequency and the mechanism of the link between a large PDA and a congenital
defect of the ciliary muscle and the iris sphincter as well as the tortuosity
of the retinal vessels. Any patient with a PDA should undergo a careful examination
of the function of the intraocular muscles.
AUTHOR INFORMATION
Michael H. Gräf, MD;
Andrea Jungherr, MD
Giessen, Germany
Corresponding author: Michael H. Gräf, MD, Department of Strabismology
and Neuro-ophthalmology, University of Giessen, Friedrichstrasse 18, D-35385
Giessen (e-mail: michael.h.graef{at}augen.med.uni-giessen.de).
REFERENCES
1. Graf M. Bilateral congenital mydriasis and lack of accommodation. Ophthalmologe. 1996;93:377-379.
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3. Buys Y, Buncic JR, Enzenauer RW, Mednick E, O'Keefe M. Congenital aplasia of the iris sphincter and dilator muscle. Can J Ophthalmol. 1993;28:72-75.
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4. Caccamise WC, Townes PL. Bilateral congenital mydriasis. Am J Ophthalmol. 1976;81:515-517.
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5. Suzuki T, Obara Y, Fujita T, Shoji E. Unilateral congenital mydriasis. Br J Ophthalmol. 1994;78:420.
6. Laor N, Korczyn AD. Waardenburg syndrome with a fixed dilated pupil. Br J Ophthalmol. 1978;62:491-494.
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7. Richardson P, Schulenburg WE. Bilateral congenital mydriasis. Br J Ophthalmol. 1992;76:632-633.
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8. Quarrell O. Gillespie syndrome reported as bilateral congenital mydriasis. Br J Ophthalmol. 1993;77:827-828.
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SECTION EDITOR: W. RICHARD GREEN, MD
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