International Ophthalmology

, Volume 33, Issue 4, pp 429–433

Management of recurrent intra corneal epithelial cyst with ethanol irrigation and vacuum-assisted cyst wall excision

Authors

Case Report

DOI: 10.1007/s10792-012-9677-3

Cite this article as:
Gokhale, N.S. Int Ophthalmol (2013) 33: 429. doi:10.1007/s10792-012-9677-3

Abstract

The clinical and pathological features and management of a patient with recurrent intracorneal epithelial cyst are reported. A child presented with a large intracorneal cyst and underwent drainage with 96 % ethanol irrigation. Histopathology confirmed the epithelial nature of the cyst. The cyst recurred, however, and subsequently a repeat ethanol irrigation with removal of the cyst wall was done. The cyst wall was vacuumed to ensure complete removal of epithelial cells. There was no recurrence, with good visual and cosmetic recovery. Intracorneal epithelial cysts can be successfully managed with drainage, 96 % ethanol irrigation, and vacuum-assisted cyst wall excision.

Keywords

Intrastromal cystCorneal cystEpithelial cyst96 % EthanolDrainageSquamous epitheliumInclusion cystvacuumingCytodestruction

Introduction

Intracorneal epithelial cysts are benign, slowly progressive lesions caused by implantation of corneal epithelium in the corneal stroma. These rare lesions may sometimes extend to involve the sclera. Proliferation of epithelial cells between collagen lamellae creates an intrastromal cyst lined by desquamating squamous epithelium. Developmental and traumatic aetiologies have been postulated [14]. Penetrating or perforating wounds and surgical trauma are the more common causes of traumatic cysts.The clinical course is typically indolent without corneal or intraocular inflammation [1]. Progressive increase in size can affect vision, thus requiring treatment [5]. Surgical procedures reported with varying degrees of success include simple cyst aspiration and drainage, cyst wall excision, chemical cautery, electrical cautery, cryotherapy, and lamellar or penetrating keratoplasty [2, 612] (Table 1). Chemical solutions described for destruction of epithelial cells include 10 % acetic acid, 1 % iodine, distilled water, cocaine, 20 % trichloroacetic acid and 96 % ethanol [2, 6, 7, 1315]. We report a rare case of a developmental intracorneal epithelial cyst that recurred after drainage and 96 % ethanol irrigation and was subsequently successfully managed with drainage, 96 % ethanol irrigation, and vacuum-assisted cyst wall excision.
Table 1

Summary of cases reported with management approaches

Author/Year/Ref. no.

Nature of cyst

n

Management approach

Bloomfield et al. (1980) [1]

Post-traumatic cyst

1

Destruction of epithelial lining

Chan et al. (1989) [2]

Traumatic corneal cysts

2

PK, excision + aqueous iodine 1 % cautery

Reed et al. (1971) [5]

Traumatic corneal cysts

8

Peripheral marsupialisation, chemical cautery (cocaine)

Rao et al. (1998) [6]

Congenital sclerocorneal cysts

3

Marsupialisation of scleral portion

Trichloroacetic acid cauterization

Liakos (1978) [7]

Congenital sclerocorneal cyst

1

Drainage, wall excision and cautery

Corneal cyst

1

Observation

Miffilin (2001) [8]

Post-surgical (squint)

1

Drainage and debridement

Mahmood et al. (1998) [9]

Congenital sclerocorneal cyst

1

Excision

Wilhelmus et al. (1992) [10]

Post-surgical (cataract)

1

Drainage, cryotherapy

Avni et al. (1989) [11]

Corneal cyst with post-PK sclera and anterior chamber extension

1

PK, YAG laser

Sano et al. (1999) [12]

Congenital (2), Post-surgical (squint) (1)

3

Lamellar keratoplasty

Ali Javadi et al. (2006) [14]

Post-surgical (squint, corneal repair)

2

Drainage, 96 % alcohol, wall excision

Shin et al. (2002) [15]

Corneoscleral cyst

1

Distilled water injection

n number of cases

Case history

A 9-year-old child presented with a history of a slowly progressive corneal opacity in the right eye since 1 year duration. There was no history of trauma, previous surgery, red eye or any other past symptoms. The child had used some drops in the past with no improvement. On examination of the right eye, vision was 20/40, lids and conjunctiva were normal, and the cornea showed a large white intrastromal cyst nasally and extending from the limbus to the mid-pupillary zone (Fig. 1). On slit section the cyst was biconvex in shape and located in the posterior stroma (Fig. 2). The overlying anterior stroma was normal and did not reveal any scar. There was no scleral extension. The rest of the ocular evaluation was normal. The left eye was normal.
https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig1_HTML.jpg
Fig. 1

Large intrastromal corneal cyst extending onto mid pupil

https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig2_HTML.jpg
Fig. 2

Biconvex cyst in the posterior cornea

A surgical intervention was planned and an incision was made over the cornea anterior to the cyst. It was deepened till the cyst wall was opened. A thick white turbid fluid was aspirated and sent for pathological evaluation. The cyst space was then irrigated with 96 % ethanol for 1 min, after which it was washed off. The incision was small and self-sealing. Postoperatively the eye was quiet and showed no inflammatory reaction. The cyst had collapsed with no retained interface fluid (Fig. 3). Prednisolone 1 % eyedrops (prednisolone; Allergan India) and tobramycin 0.3 % eyedrops (Tobrex; Alcon India) were given four times a day for 2 weeks and then stopped. Microscopic examination of the cytospin smears with haematoxylin and eosin staining showed sheets of squamous cells consistent with a diagnosis of epithelial inclusion cyst (Fig. 4).
https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig3_HTML.jpg
Fig. 3

Collapsed cyst with no interface fluid

https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig4_HTML.jpg
Fig. 4

Cytospin smears show sheets of squamous cells

On subsequent follow-up at 3 and 6 months there was minimal recurrence of fluid in the cyst. No intervention was done and the child was observed. At 12 months there was further enlargement and distension of the cyst (Fig. 5). Anterior segment optical coherence tomography (Cirrus HD-OCT; Carl Zeiss Meditec, Inc, Dublin, CA, USA) was done and showed a biconvex cyst with a maximum thickness of about 659 μm and an overlying anterior stromal thickness of 330 μm (Fig. 6).
https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig5_HTML.jpg
Fig. 5

Recurrent cyst with interface fluid

https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig6_HTML.jpg
Fig. 6

OCT image showing cyst location

A repeat surgery was advised. This time a vertical corneal incision was made very close to the edge of the cyst at the limbus and deepened till the cyst was entered. The fluid was drained and the cyst was irrigated with 96 % ethanol for 1 min. A whitening of the cyst wall was observed after ethanol injection. Ethanol was irrigated and washed at the end of 1 min. Vacuuming and manual scraping was done with a manual irrigation aspiration reverse Simcoe cannula and an aspiration cannula attached to a phacoemulsification system to remove any residual surviving epithelial cells. The cyst wall was manually scraped with a Sinskey and a reverse Sinskey hook and removed piecemeal. The vacuuming was repeated once again and the incision was closed with a single interrupted 10-0 nylon suture.

The postoperative follow-up was uneventful and at 6 months there was residual stromal haze with no recurrence of the cyst (Fig. 7). The suture was removed at this visit. There was no recurrence of the cyst at 1 year follow-up except for interface scarring (Fig. 8). The patient continues to be free of recurrence at 3 years.
https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig7_HTML.jpg
Fig. 7

Six-month postoperative picture showing no recurrence

https://static-content.springer.com/image/art%3A10.1007%2Fs10792-012-9677-3/MediaObjects/10792_2012_9677_Fig8_HTML.jpg
Fig. 8

One-year postoperative picture showing residual interface scarring

Discussion

Intracorneal epithelial cysts are rare and form due to implantation of corneal epithelial cells into the corneal stroma following developmental aberration or penetrating trauma or prior surgical interventions [14, 6]. Congenital or developmental aetiology is more common in the paediatric age group while the traumatic cases are commoner in older children and young adults. In many cases the trauma may be minor enough to be missed and no history or signs of past trauma may be found on examination. Even in cases without an overt history of trauma, undetected previous injury should be considered [7, 8, 13]. Post-surgical corneal cysts have been reported after strabismus surgery [8, 12, 14], cataract surgery [10] and corneal repair post-trauma [14]. Corneal surgeries and keratorefractive surgeries can potentially drive viable epithelial cells into the corneal stroma and can lead to intracorneal epithelial cyst formation.

The size of the lesion may vary from 1 mm to total involvement of the cornea and is usually oval or circular in shape and contains opalescent fluid. A pseudohypopyon can sometimes be observed within the cyst caused by precipitation of epithelial debris in the lower portion [1, 6, 13]. Surgical intervention is required due to involvement of the visual axis with a drop in vision or for cosmetic purposes.

Simple cyst aspiration and drainage are associated with recurrence because the epithelial cells are not destroyed [2, 6, 9]. Drainage with chemical cytodestruction is therefore a preferred modality of treatment. Corneal epithelial cysts have been successfully treated with 96 % ethanol [14]. Injection of alcohol into the collapsed cyst cavity in a closed chamber technique allows cytodestruction and minimizes inadvertent damage to the adjacent corneal stroma or endothelium. Whitening of the cyst wall on contact with ethanol ensures that cytodestruction has occurred throughout the cyst cavity. However if destruction of the epithelial cells is incomplete, remaining epithelial cells proliferate and the cyst recurs [2, 6, 9, 11]. Complete excision of the cyst wall after cytodestruction ensures that any remaining viable epithelial cells are also removed and no recurrence is possible.

Our patient was 9 years old and the cyst had been noted since 1 year duration. There was no history of trauma or surgery and no evidence of previous penetrating injury on examination. The epithelial nature of the cyst was confirmed by the histopathological observations. Drainage with 96 % ethanol injection was performed, but the cyst recurred, indicating that some viable epithelial cells survived within the cyst cavity and re-proliferated postoperatively. At the second surgery additional vacuuming was done to remove all possible epithelial cells that may have survived the alcohol irrigation. Scrape excision of the cyst wall was done followed by further vacuuming to ensure complete removal, and resulted in a successful outcome. The incision was also made at the extreme limbal edge of the cyst so as to obtain easier access to perform a more complete cyst wall excision. Vacuuming helps to remove any cyst wall or epithelial cell remnants after cyst wall excision and has not been previously described to the best of our knowledge.

We recommend a combined approach to treating these rare cysts. Cytodestruction must be combined with cyst wall excision and vacuuming to remove any residual epithelial cells, especially if the wall is removed piecemeal.

Copyright information

© Springer Science+Business Media Dordrecht 2012