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Endophthalmitis after astigmatic myopic laser in situ keratomileusis
case
reports
Endophthalmitis after astigmatic myopic laser in situ keratomileusis Mark G. Mulhern, FRCSI, Patrick I. Condon, FRCS, FRCOphth, Michael O'Keefe, FRCS, FRCOphth
ABSTRACT A 36-year-old woman had uneventful astigmatic myopic laser in situ keratomileusis (LASIK) to correct -12.00 -1.50 x 70. Three days later, she developed a corneal abscess, hypopyon, and an intense vitreous cellular reaction-endophthalmitis. The patient was immediately given intravenous ciprofloxacin and topical vancomycin and ceftazidime. The infecting organism was Streptococcus pneumoniae. One day after therapy was instituted, the hypopyon resolved. Seven months later, best corrected visual acuity was 20125 and refractive error, -4.00 diopters. A stromal scar (grade 2 haze) was causing a slight reduction in acuity. Endophthalmitis after LASIK, if treated promptly, need not lead to a permanent reduction in visual acuity. J Cataract Refract Surg 1997; 23:948-950
L
aser in situ keratomileusis (LASIK) was developed to correct high degrees of myopia (greater than 10.00 diopters [DJ) and avoid the problems that can occur after photorefractive keratectomy (PRK). Despite being an extraocular procedure, it can be associated with severe sight-threatening infection. There are three reported cases of serious infection after PRK, two infected corneal ulcers and one infected corneal ulcer and endophthalmitis.! We present the first reported case of a severe infection after LASIK.
Case Report A 36-year-old woman with an uncorrected visual acuity (UeYA) of finger counting at 1 foot and a best corrected visual acuity (BeYA) of 20/16 had astigmatic myopic LASIK to correct -12.0 -1.5 X 70. The procedure was carried out From the DepartmentoJOphthalmology, Mater Private Hospital Dublin, Ireland. Reprint requests to Patrick I Condon, FRCS, FRCOphth, Consultant Ophthalmologist, Ardkeen Hospital Waterford. County Waterford, Ireland.
948
] CATARACT REFRACT
as follows: The patient was placed under the microscope of the laser in an operating theater with a controlled clean-air environment. Several drops of a 50:50 mixture of aqueous povidone-iodine (Betadine®) and balanced salt solution (BSS) were instilled. The lashes were retracted with SteriStripsTM; a lint-free sterile drape was then placed over the patient's face. Finally, a speculum was inserted. The suction ring was affixed to the globe, with care taken not to express potentially contaminated Meibomian secretions. The micro keratome was placed on the track, and a 160 /Lm flap was cut. After the microkeratome and suction ring were removed, the flap was nasally reflected and the ablation carried out. The flap was hydrated with BSS (keeping the stromal bed dty) and repositioned on the stroma. While the flap was being hydrated, handheld suction removed pooling fluid. The entire procedure, from cutting to repositioning the flap, took about 5 to 6 minutes. The interface itself was open to the environment for about 4 minutes. No undue difficulty occurred at any stage of the procedure. At the end of the procedure, topical gentamicin was instilled, the drapes were removed, and a shield was placed on the eye. The patient was instructed to instill gentamicin drops four times daily and not to rub the eye. On the first postoperative day, the flap was in situ; the only remarkable observation was debris in the flap-bed inter-
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CASE REPORTS: MULHERN
face. The patient presented 2 days later complaining of ocular pain and discharge, which had started 24 hours previously. Visual acuity at this stage was inaccurate light projection. The left eyelids were swollen and almost completely closed. There was a purulent discharge, and the conjunctiva was intensely congested. An interface abscess with an overlying corneal epithelial defect was noted. There was also a small (l.0 mm) hypopyon and an intense vitreous cellular reactionendophthalmitis. Conjunctival swabs and corneal scrapings were taken and sent for staining and culture. During the corneal scraping, the corneal flap created by the microkeratome was sloughed off; it too was sent to the laboratoty for culture. The gram stain indicated gram-positive Diplococci suggestive of Streptococcus pneumoniae (later confirmed by culture). The patient was given intravenous ofloxacin and topical vancomycin and ceftazidime. The next day, visual acuity had improved to finger counting at 1 foot. The stromal surface laid bare by the detachment of the flap was gradually being re-epithelialized, the corneal abscess was smaller, and the hypopyon had resolved. By the sixth day, the cornea (i.e., the stroma) had fully re-epithelialized, and only a small circular stromal opacity was present. The patient was discharged 11 days after admission with a UCVA of20/200 and BCVA of 20/80 with -7.25 + 3.25 X 85. The stromal scar commenced at the anterior stromal level and approached a third of corneal thickness in depth. Two months later, UCVA had improved to 20/80 and the refraction was - 3.25 -1.50 X 130 (giving a BCVA of 20/32). Seven months later, using the Holladay Diagnostic Summaty (version 3.1, EyeSys Technologies), potential acuity was calculated as 20/10 (Figure 1). However, only 20125 (BCVA with -4.00 D) could be achieved because of corneal scarring (Figure 2).
Figure 2. (Mulhern) The stromal scar 7 months after the infection.
Discussion The risk of corneal infection increases after corneal refractive surgery. Once a corneal defect of any sort is present, the risk of infection is greater. This is more significant in cases of PRK than of LASIK, although even with the latter procedure, small epithelial defects are sometimes seen in the first few postoperative days. Some advocate the use of a bandage contact lens after PRK or LASIK. Although this may reduce pain and
Figure 1. (Mulhern) Topographical appearance at 7 months postoperatively with additional data provided by the Holladay Diagnostic Summary (version 3.1, EyeSys Technologies).
J CATARACT REFRACT SURG-VOL 23, JULY/AUGUST 1997
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CASE REPORTS: MULHERN
promote re-epithelialization, the risk of microbial keratitis and sterile corneal infiltrates is increased. 2 The therapeutic regimen after PRK or LASIK may also contribute to an ocular milieu that invites infection. The use of topical corticosteroids or nonsteroidal anti-inflammatory drugs (NSAIDs) renders the eye more susceptible to infection. A case reported by Sampath and coauthors 3 emphasizes the need to monitor closely patients on topical corticosteroids. Another predisposing factor is the reduced corneal sensitivity that persists for at least 1 month after PRK. 4 The effect of the LASIK ablation on corneal sensitivity is unknown. We do not use topical corticosteroids, NSAIDs, or bandage contact lenses after LASIK, and our patient did not have any risk factors such as blepharitis or reduced tear secretion. Apart from the effect on corneal innervation by the ablation, no obvious predisposing cause for infection could be determined; that is, until you consider the corneal interface (where the corneal abscess was originally noted) between the cap and stromal bed. The interface short-circuits the normal (ocular surface) protection afforded against infection by the corneal epithelium and Bowman's membrane, while the greatly thinned stroma further increases the accessibility of the infecting organism to the interior (i.e., anterior chamber) of the eye. Furthermore, in LASIK there is a potential source of infection from contamination of the interface with debris derived from the patient's own
950
conjunctival secretions peroperatively and from damage to the cornea by inadvertent trauma from the eyebottle dropper postoperatively. Several conclusions can be drawn from this case. Corneal scraping may result in loss of the flap; therefore, other means of obtaining material for culture should be considered (e.g., an anterior chamber tap). Also, with time, remodeling of the scar can result in changes in refraction and in the density of the scar itself. Thus, a period of at least 6 months should elapse before active intervention is considered to reduce either the residual refractive error or scar density.
References 1. Faschinger C, Faulborn J, Ganser K. Infektiose Hornhautgeschwure- einmal mit Endophthalmitis-nach PRK mit Einmalkontaktlinse. Klin Monatsbl Augenheilkd 1995; 206:96-102 2. 5her NA, Krueger RR, Teal P, et al. Role of topical corticosteroids and nonsteroidal antiinflammatory drugs in the etiology of stromal infiltrates after excimer photorefractive keratectomy (letter). J Refract Corneal 5urg
1994; 10:587-588 3. 5ampath R, Ridgway AE, Leatherbarrow B. Bacterial keratitis following excimer laser photo refractive keratectomy: a case report (letter). Eye 1994; 8:481-482 4. Ishikawa T, Park 5B, Cox C, et al. Corneal sensation following excimer laser photo refractive keratectomy in humans. J Refract Corneal 5urg 1994; 10:417-422
J CATARACT REFRACT SURG-VOL 23, JULY/AUGUST 1997
reports
Endophthalmitis after astigmatic myopic laser in situ keratomileusis Mark G. Mulhern, FRCSI, Patrick I. Condon, FRCS, FRCOphth, Michael O'Keefe, FRCS, FRCOphth
ABSTRACT A 36-year-old woman had uneventful astigmatic myopic laser in situ keratomileusis (LASIK) to correct -12.00 -1.50 x 70. Three days later, she developed a corneal abscess, hypopyon, and an intense vitreous cellular reaction-endophthalmitis. The patient was immediately given intravenous ciprofloxacin and topical vancomycin and ceftazidime. The infecting organism was Streptococcus pneumoniae. One day after therapy was instituted, the hypopyon resolved. Seven months later, best corrected visual acuity was 20125 and refractive error, -4.00 diopters. A stromal scar (grade 2 haze) was causing a slight reduction in acuity. Endophthalmitis after LASIK, if treated promptly, need not lead to a permanent reduction in visual acuity. J Cataract Refract Surg 1997; 23:948-950
L
aser in situ keratomileusis (LASIK) was developed to correct high degrees of myopia (greater than 10.00 diopters [DJ) and avoid the problems that can occur after photorefractive keratectomy (PRK). Despite being an extraocular procedure, it can be associated with severe sight-threatening infection. There are three reported cases of serious infection after PRK, two infected corneal ulcers and one infected corneal ulcer and endophthalmitis.! We present the first reported case of a severe infection after LASIK.
Case Report A 36-year-old woman with an uncorrected visual acuity (UeYA) of finger counting at 1 foot and a best corrected visual acuity (BeYA) of 20/16 had astigmatic myopic LASIK to correct -12.0 -1.5 X 70. The procedure was carried out From the DepartmentoJOphthalmology, Mater Private Hospital Dublin, Ireland. Reprint requests to Patrick I Condon, FRCS, FRCOphth, Consultant Ophthalmologist, Ardkeen Hospital Waterford. County Waterford, Ireland.
948
] CATARACT REFRACT
as follows: The patient was placed under the microscope of the laser in an operating theater with a controlled clean-air environment. Several drops of a 50:50 mixture of aqueous povidone-iodine (Betadine®) and balanced salt solution (BSS) were instilled. The lashes were retracted with SteriStripsTM; a lint-free sterile drape was then placed over the patient's face. Finally, a speculum was inserted. The suction ring was affixed to the globe, with care taken not to express potentially contaminated Meibomian secretions. The micro keratome was placed on the track, and a 160 /Lm flap was cut. After the microkeratome and suction ring were removed, the flap was nasally reflected and the ablation carried out. The flap was hydrated with BSS (keeping the stromal bed dty) and repositioned on the stroma. While the flap was being hydrated, handheld suction removed pooling fluid. The entire procedure, from cutting to repositioning the flap, took about 5 to 6 minutes. The interface itself was open to the environment for about 4 minutes. No undue difficulty occurred at any stage of the procedure. At the end of the procedure, topical gentamicin was instilled, the drapes were removed, and a shield was placed on the eye. The patient was instructed to instill gentamicin drops four times daily and not to rub the eye. On the first postoperative day, the flap was in situ; the only remarkable observation was debris in the flap-bed inter-
SURG~VOL
23,]ULY/AUGUST 1997
CASE REPORTS: MULHERN
face. The patient presented 2 days later complaining of ocular pain and discharge, which had started 24 hours previously. Visual acuity at this stage was inaccurate light projection. The left eyelids were swollen and almost completely closed. There was a purulent discharge, and the conjunctiva was intensely congested. An interface abscess with an overlying corneal epithelial defect was noted. There was also a small (l.0 mm) hypopyon and an intense vitreous cellular reactionendophthalmitis. Conjunctival swabs and corneal scrapings were taken and sent for staining and culture. During the corneal scraping, the corneal flap created by the microkeratome was sloughed off; it too was sent to the laboratoty for culture. The gram stain indicated gram-positive Diplococci suggestive of Streptococcus pneumoniae (later confirmed by culture). The patient was given intravenous ofloxacin and topical vancomycin and ceftazidime. The next day, visual acuity had improved to finger counting at 1 foot. The stromal surface laid bare by the detachment of the flap was gradually being re-epithelialized, the corneal abscess was smaller, and the hypopyon had resolved. By the sixth day, the cornea (i.e., the stroma) had fully re-epithelialized, and only a small circular stromal opacity was present. The patient was discharged 11 days after admission with a UCVA of20/200 and BCVA of 20/80 with -7.25 + 3.25 X 85. The stromal scar commenced at the anterior stromal level and approached a third of corneal thickness in depth. Two months later, UCVA had improved to 20/80 and the refraction was - 3.25 -1.50 X 130 (giving a BCVA of 20/32). Seven months later, using the Holladay Diagnostic Summaty (version 3.1, EyeSys Technologies), potential acuity was calculated as 20/10 (Figure 1). However, only 20125 (BCVA with -4.00 D) could be achieved because of corneal scarring (Figure 2).
Figure 2. (Mulhern) The stromal scar 7 months after the infection.
Discussion The risk of corneal infection increases after corneal refractive surgery. Once a corneal defect of any sort is present, the risk of infection is greater. This is more significant in cases of PRK than of LASIK, although even with the latter procedure, small epithelial defects are sometimes seen in the first few postoperative days. Some advocate the use of a bandage contact lens after PRK or LASIK. Although this may reduce pain and
Figure 1. (Mulhern) Topographical appearance at 7 months postoperatively with additional data provided by the Holladay Diagnostic Summary (version 3.1, EyeSys Technologies).
J CATARACT REFRACT SURG-VOL 23, JULY/AUGUST 1997
949
CASE REPORTS: MULHERN
promote re-epithelialization, the risk of microbial keratitis and sterile corneal infiltrates is increased. 2 The therapeutic regimen after PRK or LASIK may also contribute to an ocular milieu that invites infection. The use of topical corticosteroids or nonsteroidal anti-inflammatory drugs (NSAIDs) renders the eye more susceptible to infection. A case reported by Sampath and coauthors 3 emphasizes the need to monitor closely patients on topical corticosteroids. Another predisposing factor is the reduced corneal sensitivity that persists for at least 1 month after PRK. 4 The effect of the LASIK ablation on corneal sensitivity is unknown. We do not use topical corticosteroids, NSAIDs, or bandage contact lenses after LASIK, and our patient did not have any risk factors such as blepharitis or reduced tear secretion. Apart from the effect on corneal innervation by the ablation, no obvious predisposing cause for infection could be determined; that is, until you consider the corneal interface (where the corneal abscess was originally noted) between the cap and stromal bed. The interface short-circuits the normal (ocular surface) protection afforded against infection by the corneal epithelium and Bowman's membrane, while the greatly thinned stroma further increases the accessibility of the infecting organism to the interior (i.e., anterior chamber) of the eye. Furthermore, in LASIK there is a potential source of infection from contamination of the interface with debris derived from the patient's own
950
conjunctival secretions peroperatively and from damage to the cornea by inadvertent trauma from the eyebottle dropper postoperatively. Several conclusions can be drawn from this case. Corneal scraping may result in loss of the flap; therefore, other means of obtaining material for culture should be considered (e.g., an anterior chamber tap). Also, with time, remodeling of the scar can result in changes in refraction and in the density of the scar itself. Thus, a period of at least 6 months should elapse before active intervention is considered to reduce either the residual refractive error or scar density.
References 1. Faschinger C, Faulborn J, Ganser K. Infektiose Hornhautgeschwure- einmal mit Endophthalmitis-nach PRK mit Einmalkontaktlinse. Klin Monatsbl Augenheilkd 1995; 206:96-102 2. 5her NA, Krueger RR, Teal P, et al. Role of topical corticosteroids and nonsteroidal antiinflammatory drugs in the etiology of stromal infiltrates after excimer photorefractive keratectomy (letter). J Refract Corneal 5urg
1994; 10:587-588 3. 5ampath R, Ridgway AE, Leatherbarrow B. Bacterial keratitis following excimer laser photo refractive keratectomy: a case report (letter). Eye 1994; 8:481-482 4. Ishikawa T, Park 5B, Cox C, et al. Corneal sensation following excimer laser photo refractive keratectomy in humans. J Refract Corneal 5urg 1994; 10:417-422
J CATARACT REFRACT SURG-VOL 23, JULY/AUGUST 1997