A case of severe acute corneal hydrops with keratoconus associated with Down syndrome described in a 16-year-old male
patient presented with a sudden unilateral painful visual loss in his left eye. The anterior segment of his left eye showed a severe
diffuse edematous ectasia of acute corneal hydrops. Eye rubbing of his left eye was observed. Continued gradual improvement in his
visual acuity and a central corneal scar were detected.
Down’s syndrome is frequently associated with keratoconus,
a chronic non-inflammatory disorder which is characterized
by progressive thinning of the cornea leading to scarring and
progressive stromal thinning. Its incidence in Down’s syndrome
has been reported up to 15% [1]. Acute corneal hydrops is
characterized by marked stromal edema due to a tear in Descemet
membrane (DM) which permits aqueous to enter the corneal
stroma and epithelium [2-3].
Figure 1: Color photography of the left eye showed severe microcystic edema, bullae and conical protrusion
Figure 2: Pentacam of the right eye showed an early stage of Keratoconus.
Figure 3: Pentacam of the left eye revealed marked increase in the corneal thickness because of severe edema..
Figure 4: Anterior segment OCT of the left eye showing massive microcystic corneal edema and overlying epithelial bullae.
A 16-year-old Indian male presented with photophobia and a
central loss of vision in his left eye 3 days ago. He has a positive
history of Down syndrome associated with Keratoconus. The best
corrected visual acuity (BCVA) for far and near was unable to be
tested because of his sever mental retardation. Extraocular muscle
movements were normal. Gross inspection of the face and lids was
negative for ecchymosis, edema or asymmetry. Anterior segment
evaluation on slit lamp biomicroscope revealed that the eyelids
and lashes were clear without evidence of inflammation. The right
cornea was clear, and the left cornea showed marked edema and
central conical protrusion. The bulbar and palpebral conjunctivae
were clear without injection, chemosis, melanosis, papillae or
follicles. The Right eye showed Cerulean cataract; however,
we could not assess the left eye due to marked edema. Color
photography on the left eye detected corneal edema, bullae and
conical protrusion (Figure 1). Pentacam of the right eye showed an
early stage of Keratoconus (Figure 2) and of the left eye revealed
marked increase in the corneal thickness (Figure 3). Anterior
Chamber OCT Scan of the left eye revealed bullae edema but tear in
DM was unable to photograph because patient was uncooperative
during the investigation (Figure 4). Conservative treatment
includes sodium chloride, cyclopentolate eye drops, combination of
brimonidine and timolol with an artificial lubricant eye drops for
symptomatic relief. A contact lens could not be used because the
patient was uncooperative. Intracameral C3F8 gas injection was
recommended to speed the recovery if there was no improvement
with the medical treatment.
Gradual improvement in 4 weeks but extensive residual
scarring and corneal irregularities were the cause of reduced visual
acuity. Penetrating Keratoplasty (PK) was discussed but it was
difficult because of low economic status and his mental retardation.
Keratoconus is characterized by progressive thinning and
protrusion of the cornea. Thus, Patients suffer from irregular
astigmatism and impairment in visual function [4]. Acute corneal
hydrops is caused by tear in Descemet’s membrane which allows
influx of fluid from the aqueous humor to the corneal stroma
leading to acute corneal edema and formation of cystic spaces.
This edema remains for few weeks and rapid management is
encouraged because it could prevent the formation of a fistula and
leakage from the aqueous humor [5-6]. The edema tends to resolve
with extensive scarring. Keratoconus is one of eye features of Down
Syndrome. Eye rubbing is one of the underestimated risk factors
for development of acute hydrops in Keratoconus, especially with
Down’s syndrome patients [7-9]. Conservative treatment includes
hypertonic saline, lubricants, cyclopentolate and anti-glaucoma
eye drops are used till spontaneous resolutions occurs [10].
Intracameral Air/Gas injections showed remarkable results by
reattaching the Descemet membrane back to the corneal stroma.
The Gas blocks fluid from AC to the cornea results in reduced
corneal swelling and accelerated healing process. PK is usually the
treatment of choice in ectatic patients who previously developed
hydrops, studies have been inconclusive regarding differences in
graft survival between grafts with prior episodes of hydrops and
grafts without prior hydrops [11].
Acute corneal hydrops should be considered one of the important
eye features for the diagnosis of Down syndrome. Patients and their
family should be warned of the eye rubbing. Treatment could be
conservative or interventional, including intracameral injections
and Penetrating Keratoplasty which is very challenging in mentally
retarded patients. New treatments such as compressive sutures
and tissue adhesive should be considered. We believe that there is
no establishing approach to deal with a challenging problem like
acute hydrops in down’s syndrome patient with severe mental
retardation. Those patients can not co-operate during examination
and intervention therapy. They have behavioral disorders, hearing
problems in addition to decreased cognitive functions. Educational
programs for patients, family and doctors are necessary. Moreover,
routine screening could be the most important method to discover
the disorders earlier and may help prevent future complications.