0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Clinicopathologic Reports, Case Reports, and Small Case Series |

Histopathological Analysis of the Cornea After Laser In Situ Keratomileusis FREE

J. Brooks Crawford, MD; Anthony J. Aldave, MD; Stephen McLeod, MD; Edward Howes, MD; Daniel Schwartz, MD
[+] Author Affiliations

Section Editor: W. Richard Green, MD

More Author Information
Arch Ophthalmol. 2003;121(6):896-898. doi:10.1001/archopht.121.6.896.
Text Size: A A A
Published online

We report a case of an intact laser in situ keratomileusis (LASIK) flap despite traumatic rupture of the eye 13 months postoperatively. An eye that had undergone a successful LASIK procedure was ruptured in an airplane crash 13 months postoperatively. The cornea developed blood staining. A keratoprosthesis was placed so the posterior pole of the eye could be evaluated and then was replaced with a donor corneal graft. The recipient cornea, which included the LASIK flap, was examined by histologic analysis. Despite major ocular trauma 13 months after LASIK, the flap was intact. Keratocytes were diminished in the flap. Blood staining was minimal in the flap but pronounced in the underlying corneal stroma.

A 59-year-old flight instructor, who had undergone bilateral LASIK procedures 12 and 13 months earlier, crashed his single-engine airplane and hit the instrument panel. He suffered deep facial lacerations, including almost complete avulsion of his nose and severe bilateral eye trauma. Examination and limited exploration of his eyes at the time of surgery for his facial wounds showed a visual acuity of no light perception OD and light perception OS, an intraocular pressure of 6 mmHg OU, a clear cornea and anterior chamber in both eyes, a dislocated lens in the right eye, and blood in the vitreous, retina, and choroid of both eyes.

Two weeks later, exploratory ocular surgery was performed. The right cornea was brown (bloodstained), so a vitrectomy could not be performed. Blood was irrigated from the anterior chamber and was released from the subchoroidal space through a pars plana stab incision. In the left eye, vitreous blood was removed by vitrectomy, and subchoroidal blood was removed by sclerostomy.

Two months later, the patient was referred to the retina service at the University of California, San Francisco, for further evaluation and treatment. Visual acuity was light perception OD and counting fingers OS. Exploration of the right eye showed an occult scleral rupture. An encircling band was placed. A keratoprosthesis was placed so the posterior pole could be examined. The detached and incarcerated retina, associated with proliferative vitreoretinopathy and retinal and choroidal blood, was inoperable. The keratoprosthesis was replaced with a donor cornea.

The cornea that had been removed to place the keratoprosthesis included the LASIK flap. It was placed in formalin and processed for histologic sections, which were stained with hematoxylin-eosin, periodic acid–Schiff, Prussian blue, Masson trichrome, and Bodian stains.

The flap from the LASIK surgery was in place. In the periphery, the superficial and deeper stroma showed no artifactitious separation and no difference in histologic appearance, suggesting a firm attachment between the two. In the center of the cornea, artifactitious separation of the flap from the underlying stroma was apparent, and the histologic appearance of the flap differed from that of the underlying layers. This was consistent with an absence of healing or scarring centrally. Keratocytes were diminished in the flap (Figure 1). Blood staining, very subtle with the hematoxylin-eosin stain, was vividly demonstrated with the Masson trichrome stain (Figure 2). The hemoglobin particles were mostly confined to the stroma below the flap and appeared to pile up at the flap interface. The Prussian blue stain showed a paracentral epithelial iron line but no iron staining in the corneal stroma. The Bodian stain showed a paucity of nerve fibers traversing the Bowman layer.

Place holder to copy figure label and caption
Figure 1.

Central cornea of a patient with traumatic rupture of the eye 13 months after laser in situ keratomileusis. Note the artifactitious separation (arrow) between the flap and the underlying corneal bed and the lack of scarring at this interface. Also note the relative paucity of keratocyte nuclei above this level compared with the underlying stroma. Hemoglobin particles are not apparent with this stain (hematoxylin-eosin, original magnification ×10).

Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.

Central cornea of a patient with traumatic rupture of the eye 13 months after laser in situ keratomileusis. Note the granular staining of hemoglobin particles below the flap and the piling up of these particles at the interface (arrow), with few particles in the overlying flap (Masson trichrome, original magnification ×10).

Graphic Jump Location

Evidence from human studies with confocal microscopy and from experimental studies of wound healing after LASIK in rabbits has shown that healing after this procedure is usually limited to the peripheral edge of the flap.13 The healing sequence in the experimental rabbits is as follows: a localized and limited epithelial plug develops, which interacts with the adjacent corneal stroma and may release cytokines that produce both keratocyte activation and apoptosis.2 Extracellular matrix proteins such as fibronectin and tenascin are limited to the edge of the flap and lead to local wound healing.

Anderson et al4 examined the histologic and ultrastructural features of human corneas after successful LASIK in 2 patients postmortem. As in our case 13 months postoperatively, at 20 months postoperatively their case showed occasional areas of artifactitious separation between the flap and the underlying interface centrally with virtually no active wound healing except at the flap edge. Of the 6 previously reported clinicopathological studies of human corneas after LASIK, only the 2 cases in the study by Anderson et al were from uncomplicated procedures.1,48 This is the third such case.

Traumatic flap dislocations are rare, but they have been reported after basketball, snowball, dog paw, finger, and airbag injuries as long as 38 months after successful surgery.912 The limited peripheral wound healing in most cases, including this case, that received major trauma (eg, ruptured globe, dislocated lens, intraocular hemorrhage, and retinal detachment) is sufficient to secure the flap.

In our case, there were fewer keratocytes in the flap 13 months after LASIK. Using confocal microscopy, Vesaluoma et al13 found loss of keratocytes in the anterior layers of the flap 6 months postoperatively that persisted for up to 2 years. Whether this is the result of apoptosis of keratocytes, lack of communication with lost sensory stromal nerves, or something else has not been determined. Mitooka et al, 14 using confocal microscopy, confirmed this finding and also found fewer keratocytes in the area beneath the flap.

Although the Bodian stain showed a paucity of nerve fibers in the flap, 2 cases of corneal blood staining from our laboratory that had not undergone LASIK also had few corneal nerves crossing the Bowman layer, so conclusions about corneal nerve degeneration after LASIK cannot be established from this case.

The vivid staining of the hemoglobin particles with the Masson trichrome stain compared with their almost complete lack of visibility with hematoxylin-eosin was remarkable and demonstrates another histologic method to evaluate corneal blood staining. Another interesting feature in this case was the apparent barrier to blood staining at the interface of the LASIK flap with the underlying corneal stroma.

The authors have no relevant financial interest in this article.

Corresponding author: J. Brooks Crawford, MD, Department of Ophthalmology, University of California, San Francisco, K-219, Box 0730, 10 Kirkham St, San Francisco, CA 94143 (e-mail: brooksc@itsa.ucsf.edu).

Latvala  TBarraquer-Coll  CTervo  KTervo  T Corneal wound healing and nerve morphology after excimer laser in situ keratomileusis in human eyes. J Refract Surg. 1996;12677- 683
Perez-Santonja  JJLinna  TUTervo  KM  et al.  Corneal wound healing after laser in situ keratomileusis in rabbits. J Refract Surg. 1998;14602- 609
Vesaluoma  MHPetroll  WMPérez-Santonja  JJ  et al.  Laser in situ keratomileusis flap margin: wound healing and complications imaged by in vivo confocal microscopy. Am J Ophthalmol. 2000;130564- 573
Link to Article
Anderson  NJEdelhauser  HFSharara  N  et al.  Histologic and ultrastructural findings in human corneas after successful laser in situ keratomileusis. Arch Ophthalmol. 2002;120288- 293
Link to Article
Wright  JDNeubauer  CCStevents  G Epithelial ingrowth in a corneal graft treated by in situ keratomileusis: light and electron microscopy. J Cataract Refract Surg. 2000;2649- 55
Link to Article
Jabbur  NSStark  WJGreen  WR Corneal ectasia after laser-assisted in situ keratomileusis. Arch Ophthalmol. 2001;1191714- 1716
Link to Article
Geggei  HSTalley  AR Delayed onset keratoectasia following laser in situ keratomileusis. J Cataract Refract Surg. 1999;25582- 586
Link to Article
Rumelt  SCohen  ISkandarani  P  et al.  Ultrastructure of the lamellar corneal wound after laser in situ keratomileusis in human eye. J Cataract Refract Surg. 2001;271323- 1327
Link to Article
Lemley  HLChodosh  JWolf  TC  et al.  Partial dislocation of laser in situ keratomileusis flap by air bag injury. J Refract Surg. 2000;16373- 374
Melki  SATalamo  JHDemetriades  AM  et al.  Late traumatic dislocation of laser in situ keratomileusis corneal flaps. Ophthalmology. 2000;1072136- 2139
Link to Article
Patel  CKHanson  RMcDonald  BCox  N Late dislocation of a LASIK flap caused by a fingernail. Arch Ophthalmol. 2001;119447- 449
Iskander  NGPeters  NTPenno  EAGimbel  HV Late traumatic flap dislocation after laser in situ keratomileusis. J Cataract Refract Surg. 2001;271111- 1114
Link to Article
Vesaluoma  MPérez-Santonja  JPetroll  WM  et al.  Corneal stromal changes induced by myopic LASIK. Invest Ophthalmol Vis Sci. 2000;41369- 376
Mitooka  KRamirez  MMaguire  LJ  et al.  Keratocyte density of central human cornea after laser in situ keratomileusis. Am J Ophthalmol. 2002;133307- 314
Link to Article

Figures

Place holder to copy figure label and caption
Figure 1.

Central cornea of a patient with traumatic rupture of the eye 13 months after laser in situ keratomileusis. Note the artifactitious separation (arrow) between the flap and the underlying corneal bed and the lack of scarring at this interface. Also note the relative paucity of keratocyte nuclei above this level compared with the underlying stroma. Hemoglobin particles are not apparent with this stain (hematoxylin-eosin, original magnification ×10).

Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.

Central cornea of a patient with traumatic rupture of the eye 13 months after laser in situ keratomileusis. Note the granular staining of hemoglobin particles below the flap and the piling up of these particles at the interface (arrow), with few particles in the overlying flap (Masson trichrome, original magnification ×10).

Graphic Jump Location

Tables

References

Latvala  TBarraquer-Coll  CTervo  KTervo  T Corneal wound healing and nerve morphology after excimer laser in situ keratomileusis in human eyes. J Refract Surg. 1996;12677- 683
Perez-Santonja  JJLinna  TUTervo  KM  et al.  Corneal wound healing after laser in situ keratomileusis in rabbits. J Refract Surg. 1998;14602- 609
Vesaluoma  MHPetroll  WMPérez-Santonja  JJ  et al.  Laser in situ keratomileusis flap margin: wound healing and complications imaged by in vivo confocal microscopy. Am J Ophthalmol. 2000;130564- 573
Link to Article
Anderson  NJEdelhauser  HFSharara  N  et al.  Histologic and ultrastructural findings in human corneas after successful laser in situ keratomileusis. Arch Ophthalmol. 2002;120288- 293
Link to Article
Wright  JDNeubauer  CCStevents  G Epithelial ingrowth in a corneal graft treated by in situ keratomileusis: light and electron microscopy. J Cataract Refract Surg. 2000;2649- 55
Link to Article
Jabbur  NSStark  WJGreen  WR Corneal ectasia after laser-assisted in situ keratomileusis. Arch Ophthalmol. 2001;1191714- 1716
Link to Article
Geggei  HSTalley  AR Delayed onset keratoectasia following laser in situ keratomileusis. J Cataract Refract Surg. 1999;25582- 586
Link to Article
Rumelt  SCohen  ISkandarani  P  et al.  Ultrastructure of the lamellar corneal wound after laser in situ keratomileusis in human eye. J Cataract Refract Surg. 2001;271323- 1327
Link to Article
Lemley  HLChodosh  JWolf  TC  et al.  Partial dislocation of laser in situ keratomileusis flap by air bag injury. J Refract Surg. 2000;16373- 374
Melki  SATalamo  JHDemetriades  AM  et al.  Late traumatic dislocation of laser in situ keratomileusis corneal flaps. Ophthalmology. 2000;1072136- 2139
Link to Article
Patel  CKHanson  RMcDonald  BCox  N Late dislocation of a LASIK flap caused by a fingernail. Arch Ophthalmol. 2001;119447- 449
Iskander  NGPeters  NTPenno  EAGimbel  HV Late traumatic flap dislocation after laser in situ keratomileusis. J Cataract Refract Surg. 2001;271111- 1114
Link to Article
Vesaluoma  MPérez-Santonja  JPetroll  WM  et al.  Corneal stromal changes induced by myopic LASIK. Invest Ophthalmol Vis Sci. 2000;41369- 376
Mitooka  KRamirez  MMaguire  LJ  et al.  Keratocyte density of central human cornea after laser in situ keratomileusis. Am J Ophthalmol. 2002;133307- 314
Link to Article

Correspondence

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.
Submit a Comment

Multimedia

Some tools below are only available to our subscribers or users with an online account.

Web of Science® Times Cited: 1

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles
Risk Factors in Post-LASIK Corneal Ectasia. J Ophthalmol 2014;2014():204191.