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Anterior Segment Optical
Coherence Tomography
Findings of Acute Hydrops in a
Patient With Keratoconus
Beril R. Kucumen, MD
Nursal Melda Yenerel, MD
Ebru Gorgun, MD
Umut Asli Dinc, MD
ABSTRACT
The authors describe the anterior segment optical coherence tomography (AS-OCT) findings of a 25-year-old
patient with acute hydrops associated with keratoconus.
The patient presented with decreased visual acuity, pain,
and redness in the left eye. The symptoms, clinical presentation, and topographical findings of the right eye
confirmed this condition to be acute corneal hydrops.
The patient was closely followed up with hyper-osmotic
(NaCl 5%) and nonsteroidal anti-inflammatory (ketorolac tromethamine 0.5%) topical treatment. At the initial
examination and during follow-up, the evaluation of the
anterior segment was performed using optical coherence
tomography. Changes in the stroma and Descemet’s membrane during the healing process of acute hydrops could
be demonstrated by high-resolution AS-OCT. [Ophthalmic Surg Lasers Imaging 2010;41:S114-S116.]
INTRODUCTION
Acute hydrops is a rare complication of keratoconus
that is caused by a rupture in Descemet’s membrane.1
This rupture causes endothelial dysfunction and/or absence that allows aqueous humor to enter the corneal
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stroma and results in intrastromal edema and clefts.
Patients often present with spontaneous onset of pain,
photophobia, and blurred vision; eye rubbing and allergy may be risk factors. This condition can also be seen
in patients with pellucid marginal degeneration.2
We describe a case of acute hydrops associated with
keratoconus in which we investigated the corneal morphology by anterior segment optical coherence tomography (AS-OCT).
CASE REPORT
A 25-year-old man was referred to our University Eye
Clinic with complaints of spontaneous sudden onset of
pain, decrease of vision, epiphora, and photophobia of the
left eye. He had been diagnosed as having keratoconus
18 months prior. The slit-lamp findings from September
2007 revealed Vogt stria, Munson’s sign, and apical scar
of the left cornea; the patient was contact lens intolerant
and scheduled for keratoplasty at that time. The ophthalmological examination from January 2009 included
autorefraction, uncorrected visual acuity (UCVA), best
spectacle-corrected visual acuity, intraocular pressure, slitlamp examination, and dilated fundus examination. The
follow-up examinations were performed monthly. The
best spectacle-corrected visual acuity of the right eye was
20/30, whereas UCVA of the left eye was hand motions
and could not be raised by correction.
Slit-lamp examination of the left eye revealed a central edematous corneal hydrops (Fig. 1). One month
later, the UCVA increased to counting fingers from 15
cm; the edematous zone had decreased in diameter and
the subjective complaints of the patient regarding pain
had decreased. The patient did not come to his regular
examination in the following month for personal reasons. Three months later, the UCVA of the left eye had
From the Department of Ophthalmology, Yeditepe University Eye Hospital, Istanbul, Turkey.
Originally submitted May 12, 2009. Accepted for publication March 19, 2010.
The authors have no financial or proprietary interest in the materials presented herein.
Address correspondence to Beril R. Kucumen, MD, Yeditepe University Eye Hospital, Department of Ophthalmology, Gazi Umur Pasa Sok.25, Balmumcu,
Besiktas, Istanbul, Turkey. E-mail: [email protected]
doi: 10.3928/15428877-20101031-12
S114 Copyright © SLACK Incorporated
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Figure 1. Appearance of acute hydrops in keratoconus by slitlamp examination at presentation.
increased to counting fingers from 30 cm and the hydrops had become smaller in diameter. A full ophthalmological examination, photodocumentation of the anterior segment, and anterior segment optical coherence
tomography (AS-OCT) were performed at each visit.
Intrastromal confluent pseudocysts could be demonstrated in high-resolution cornea images by the Visante
OCT (Carl Zeiss Meditec, Inc., Dublin, CA) (Fig. 2).
DISCUSSION
AS-OCT is a new imaging technique that allows
cross-sectional, clear visualization and accurate in-depth
imaging of the anterior segment, enabling qualitative and
quantitative analysis of the corneal layers at different levels, especially when the cornea is opaque.3 High-resolution
corneal images can be recorded in any desired meridian by
Visante OCT, enabling us to evaluate the posterior cornea that cannot be otherwise thoroughly visualized. This
modality improved our evaluation of the posterior corneal
morphology that was not visible by the slit-lamp examination. Imaging of Descemet’s membrane detachment using
AS-OCT has been reported previously.4
In our case, AS-OCT demonstrated the detailed
structure of intrastromal clefts in high-resolution corneal images. During follow-up, it was especially valuable
in evaluating the thinnest part of the cornea that carries
perforation risk. This portion of the cornea was previously defined as descemetocele.5 We measured the thickness of this vulnerable location of the cornea that consisted of intact epithelium and a narrow band of anterior
stroma as 150 microns by the calipers of Visante OCT
(Fig. 1A). We would suggest the term epitheliocele instead of descemetocele for the description of this lesion
Figure 2. Anterior segment optical coherence tomography (AS-OCT)
images of acute hydrops in chronological order. The findings were similar in four quadrants; therefore, only horizontal images have been presented for comparison. (A) High-resolution corneal image on horizontal
meridian at presentation. A large defect in the Descemet’s membrane
is noticeable. There are numerous stromal pseudocysts with different
sizes having contact with each other in a petalloid pattern. White arrow
indicates the thinnest part of the cornea—the epitheliocele. The diameter of the edematous zone in the cornea was measured as 6.03 mm;
the thickness was 1.61 mm. (B) AS-OCT image of the eye 1 month
later. The pseudocysts in the anterior stroma tend to coalesce and form
a big conical pseudocyst posteriorly. The epitheliocele has become
thicker; the Descemet’s membrane shows a double contour at one
end. (C) AS-OCT image of the eye 2 months later. One big pseudocyst has formed between the Descemet’s membrane and stroma. The
free edges of the Descemet’s membrane are rolled inward and appear
thicker. (D) AS-OCT image of the eye 4 months later. The epitheliocele
has disappeared. The corneal stroma appears considerably normal
with no clefts between the lamellae. The pseudocyst is narrower with
a smooth lining. The diameter of the edematous zone in the cornea
decreased to 5.23 mm and the thickness reduced to 0.84 mm.
Ophthalmic Surgery, Lasers & Imaging · Vol. 41, No. 6 (Suppl), 2010
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highlighted the biomechanism of acute hydrops. We were
able to demonstrate the central rupture in the Descemet’s
membrane and could follow up its natural healing process. The central defect was polygonal rather than linear
and became smaller, similar to the healing of epithelial
defects of the cornea but more slowly (Figs. 2 and 3). This
is probably due to the slow formation and repair of the
Descemet’s membrane by endothelial cells. The defect
in Descemet’s membrane gets smaller at the same time
the edematous zone in the anterior cornea gets smaller in
diameter. But there may be variation in the area of the
cornea actually scanned due to the centralization of the
affected area; therefore, we may not be able to scan the
same cross-section at every examination.
Corneal perforation is a rare complication of acute
hydrops that has been reported previously.5-7 Aldave et
al. reported 3 cases with spontaneous perforation in
acute hydrops, but they also mentioned that this condition is typically self-limited in most of the cases and
resolves over a period of 6 to 10 weeks as endothelial
cells migrate over the exposed stroma forming a thin
portion of Descemet’s membrane.5
In our opinion, high-resolution AS-OCT may be
helpful in predicting a possible spontaneous perforation that fortunately did not occur in this patient. This
imaging technique is supportive in close follow-up of
patients with imminent perforation.
High-resolution AS-OCT is efficient in determining the detailed structure of corneal changes and biomechanism causing acute hydrops in keratoconus.
REFERENCES
Figure 3. 4-quad high-resolution anterior segment optical coherence tomography image of the cornea demonstrating the polygonal shape of the Descemet’s break. (A) The AS-OCT image from
180° to 0° reveals a broad paracentral defect of the posterior
corneal surface. (B) High-resolution AS-OCT image from 225°
to 45°. (C) High-resolution AS-OCT image from 270° to 90°. (D)
High-resolution image from 315° to 135°. The width of the break in
Descemet’s membrane was measured differently at each scan.
because it does not contain the Descemet’s membrane at
that location.
The pathophysiology and healing process of acute hydrops was not well understood until recently. It has been
suggested that a large central Descemet rupture causes
sudden influx of aqueous humor into the stroma, creating pocket-like cystic formations (pseudocysts) that may
reach the corneal surface.6 High-resolution AS-OCT also
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