Delayed diffuse lamellar keratitis after laser in situ keratomileusis

Diffuse lamellar keratitis as a rare complication of diamond burr superficial keratectomy for recurrent corneal erosion: a case report

Background

To present a case with a history of laser in situ keratomileusis (LASIK) developing diffuse lamellar keratitis (DLK) after diamond burr superficial keratectomy (DBSK) for recurrent corneal erosion (RCE).

Case presentation

A 25-year-old man presented with multiple episodes of RCE one year after femtosecond-assisted LASIK for myopia correction. Because conservative treatments failed to halt the repetitive attack of RCE, he underwent epithelial debridement and DBSK. However, severe foreign body sensation and blurred vision developed on postoperative day one. The next day, slit lamp biomicroscopy revealed DLK manifested as diffuse granular infiltrates at the flap interface. After topical corticosteroid treatment, the inflammation resolved gradually, and his vision recovered to 20/20.

Conclusions

Diffuse lamellar keratitis is a rare post-LASIK complication that can be triggered by DBSK, which causes impairment of the corneal epithelial integrity and subsequent inflammation at the flap interface. For post-LASIK patients with RCE, alternative treatments, such as anterior stromal puncture, may be considered to avoid extensive disruption of corneal epithelium and DLK development depending on the size and the location of the lesions.

Five-Year Incidence, Management, and Visual Outcomes of Diffuse Lamellar Keratitis after Femtosecond-Assisted LASIK

Femtosecond (FS) lasers initially had a higher incidence of diffuse lamellar keratitis (DLK) compared with microkeratome flap creation. It has been theorized that higher-frequency lower-energy (HFLE) FS lasers would reduce the incidence of DLK. Our study sought to evaluate the incidence of newer HFLE FS lasers with pulse frequencies above 60 kHz. It was a retrospective case-control study evaluating the incidence of DLK following flap creation with one of three FS lasers (AMO iFs, WaveLight FS200, Zeiss VisuMax). Uncomplicated LASIK cases were included as the control group (14,348 eyes) and cases of DLK were recorded in the study group (637 eyes). Of the 637 cases of DLK, 76 developed stage II, 25 progressed to stage III, and only three developed stage IV DLK. The overall incidence rate of DLK was 4.3%; it has fallen with the invention of newer HFLE FS lasers and is approaching the DLK incidence rates of DLK with microkeratome.

Delayed onset diffuse lamellar keratitis following enhancement LASIK surgery

BACKGROUND

Diffuse lamellar keratitis (DLK) is a relatively uncommon complication of the refractive procedure, laser-assisted in situ keratomileusis (LASIK). If detected and diagnosed in a timely fashion, it can be treated and should resolve with minimal sequelae. If untreated, or misdiagnosed and treated incorrectly, there may be loss of visual acuity. Optometrists should be familiar with this condition, its signs, symptoms and correct treatment protocol.

CASE HISTORY

A 58-year-old male Caucasian developed delayed onset diffuse lamellar keratitis, seemingly in the absence of an epithelial defect, 25 days following an enhancement LASIK procedure to his right eye. The DLK in this patient is delayed longer than typically reported in the literature. Subsequent management with topical steroids was complicated as the patient was a steroid responder and developed a markedly raised intraocular pressure that was managed with a topical anti-glaucoma agent. The diagnosis, pathogenesis and issues relevant to the treatment of this condition are discussed.

CONCLUSION

Optometrists, particularly those actively participating in the shared care of refractive surgery patients, must be familiar with diffuse lamellar keratitis so that diagnosis is not delayed. As the number of cases of refractive surgery in Australia increases, optometrists will encounter this condition more frequently.

Pathophysiology and Treatment of Diffuse Lamellar Keratitis

PURPOSE

To review cytokine- and chemokine-mediated mechanisms of diffuse lamellar keratitis (DLK) after lamellar corneal surgical procedures.

METHODS

Review of the basic science and clinical literature.

RESULTS

DLK can occur early or late (months to decades) after all lamellar corneal surgeries, including laser in situ keratomileusis, small incision lenticule extraction, anterior lamellar keratoplasty, and Descemet's stripping automated endothelial keratoplasty. It is most commonly triggered by epithelial injury during or after lamellar surgery, which leads to the release of interleukin (IL)-1α, IL-1β, and tumor necrosis factor (TNF)-α from the epithelium and into the stroma. These chemokines directly attract inflammatory cells into the cornea from the limbal blood vessels and also bind to receptors on keratocytes and corneal fibroblasts where myriad chemokines are upregulated that also chemotactically attract monocytes, macrophages, granulocytes, lymphocytes, and other bone marrow-derived cells into the corneal stroma. Other factors that can trigger DLK include retained blood in the interface, endotoxins and other toxins, and excessive keratocyte necrosis caused by femtosecond lasers. Infiltrating cells show a preference to enter any lamellar interface in the cornea, regardless of the time since surgery, because of the ease of movement toward the chemotactic attractants relative to the surrounding stroma with intact collagen lamellae and stromal cells that serve as relative barriers impeding motility. The mainstay of treatment is topical corticosteroids, but severe cases may also be treated with flap lift irrigation and systemic corticosteroids.

CONCLUSIONS

DLK can occur early or late after any lamellar corneal surgical procedure and is most commonly triggered by epithelial-stromal-bone marrow-derived cellular interactions mediated by corneal cytokines and chemokines. [J Refract Surg. 2020;36(2):124-130.].

Late-onset diffuse lamellar keratitis following laser in situ keratomileusis

OBJECTIVE

To analyze 12 cases of late-onset diffuse lamellar keratitis (DLK) following uncomplicated LASIK and propose a method of management.

DESIGN

Retrospective observational case series, literature review.

PARTICIPANTS

Patients who developed late-onset DLK following LASIK.

METHODS

Retrospective chart review of all patients with late-onset DLK from January 2014 to August 2015. Data collected included demographic information, probable cause of DLK, stage of DLK, baseline examination, treatment, clinical course, outcomes, complications, and last follow-up examination. Review of relevant literature included searching for all prior cases and case series relating to "diffuse lamellar keratitis," "late-onset DLK," "Secondary Sands," and "delayed-onset DLK" by searching PubMed with these search terms.

RESULTS

Twelve eyes of 11 patients presented with late-onset DLK following LASIK. Onset ranged from 8 months to 17 years following LASIK. Stage of DLK ranged from stage I to III, and all patients responded well to aggressive corticosteroids without lifting of the LASIK flap. Final visual acuity for stage I/II and III eyes did not demonstrate a significant difference (p = 0.218). DLK resolved by a mean of 4.86 weeks for all eyes.

CONCLUSION

Late-onset DLK can present at any time following LASIK with a wide range of inciting factors causing a nonspecific (and likely immune-related) inflammatory reaction. Based on our findings, aggressive oral and topical corticosteroids should be tried before lifting the LASIK flap as long as infection is not suspected or inciting debris is not seen in the flap because the vast majority resolve with such therapy.

Incidence of diffuse lamellar keratitis after laser in situ keratomileusis associated with the IntraLase 15 kHz femtosecond laser and Moria M2 microkeratome

PURPOSE

To analyze the incidence of diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) performed with an IntraLase 15 kHz femtosecond laser (IntraLase, Corp.) or a Moria M2 mechanical microkeratome (Moria SA).

SETTING

Vissum Madrid, Madrid, Spain.

METHODS

This retrospective study compared the incidence of DLK in consecutive LASIK procedures performed with the IntraLase 15 kHz femtosecond laser (study group) or the Moria M2 microkeratome (control group). Two surgeons performed both types of surgeries (femtosecond laser and microkeratome) using the same excimer laser (Technolas 217, Bausch & Lomb). During the first week postoperatively, topical dexamethasone drops were applied 8 times daily in the femtosecond group and 4 times daily in the mechanical microkeratome group.

RESULTS

A total of 2000 consecutive eyes were analyzed (1000 eyes in each group). Diffuse lamellar keratitis stage 2 developed in 1 patient in each group; DLK stage 3 developed in 4 patients in the study group and in no patient in the control group (P = .03).

CONCLUSION

Despite more intense postoperative steroid treatment, DLK seemed to occur more frequently after LASIK performed with the IntraLase 15 kHz femtosecond laser than after LASIK performed with the Moria M2 microkeratome.

Surgical glove-associated diffuse lamellar keratitis

PURPOSE

To demonstrate a potential cause of a prolonged epidemic of diffuse lamellar keratitis (DLK).

METHOD

This retrospective review analyzed an epidemic of diffuse lamellar keratitis over a 3-year period in a single surgery center. Altering the brand of surgical gloves used during surgery was associated with an elimination of the DLK epidemic. Optical microscopy, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and Fourier transform infrared (FTIR) spectroscopy were performed on both brands of surgical gloves to allow for comparisons and determine possible surface contaminants responsible for the DLK outbreaks.

RESULTS

The incidence of DLK during the epidemic ranged from 2% to 38% on a quarterly basis for the 3-year period. A change in the brand of surgical gloves resulted in a cessation of DLK. Surface analysis of both brands of gloves revealed extensive silicone oil contamination on the internal and external surfaces of the DLK-associated gloves and insignificant amounts of silicone oil on the external surface of the DLK-free gloves.

CONCLUSION

Silicone oil contamination of surgical gloves appears to be associated with epidemic DLK.

Safety, efficacy, and stability indices of LASEK correction in moderate myopia and astigmatism

PURPOSE

To evaluate the visual outcomes and complications in low to moderate levels of myopia and astigmatism treated with laser-assisted subepithelial keratectomy (LASEK) with a focus on postoperative recovery.

SETTING

Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA.

METHODS

A retrospective analysis of a case series of eyes treated with LASEK from 1996 to July 2002 with a follow-up of 2 years was performed. The LASEK technique involved creating an epithelial flap with 25 to 45 seconds of exposure to 20% alcohol, ablating the corneal surface using 3 different excimer lasers and nomogram adjustment, and repositioning the flap and applying a bandage contact lens. The main outcome measures were uncorrected visual acuity (UCVA), efficacy index, manifest refraction, best spectacle-corrected visual acuity (BSCVA), safety index, retreatment rate, and complications.

RESULTS

One hundred seventy-one eyes (85 right eyes and 86 left eyes) of 105 patients were studied. Preoperatively, the mean spherical equivalent was -2.99 diopters (D) +/- 1.43 (SD) (range -0.38 to -7.75 D) and the mean cylinder, -0.78 +/- 0.73 D. The UCVA ranged from 20/800 to 20/32, and the BSCVA ranged from 20/63 to 20/16; the median was 20/20. One week postoperatively, 96% of eyes had a UCVA of 20/40 or better but definitive visual recovery took more than 4 weeks in some eyes. Approximately 95% of eyes were within +/-1.0 D of emmetropia after 4 to 52 weeks; the remaining 5% did not show major deviations. At 4 to 52 weeks, only 1 eye was overcorrected by more than 1.0 D of manifest refraction. The safety index remained close to 1.0 for the follow-up after 4 weeks. The efficacy index displayed a plateau at 0.9 from 1 month to 1 year. No serious complication (including recurrent erosion syndrome) was encountered. The mean follow-up was 31 weeks, and the retreatment rate was 2.9% up to 2 years of follow-up.

CONCLUSIONS

The long-term safety and effectiveness of LASEK for the correction of low to moderate myopia and astigmatism were demonstrated. The treatment effect stabilized after 4 weeks.

Pressure-Induced Interface Keratitis: A Late Complication Following LASIK

PURPOSE

Interface inflammation is a common complication of laser in situ keratomileusis (LASIK). The most well-described presentation is diffuse lamellar keratitis (DLK), which typically develops early after LASIK and responds quickly to topical steroids. In this report, we describe a novel presentation of interface inflammation that resembles DLK in appearance but presents late in the postoperative period, is associated with increased intraocular pressure, and is exacerbated by steroid treatment.

METHODS

A retrospective case series and chart review of all patients treated in our tertiary care private practice for late-onset interface inflammation associated with elevated intraocular pressure.

RESULTS

Ten eyes in 6 patients with late-onset interface inflammation and increased intraocular pressure were identified. At presentation, all patients were presumed to have classic DLK and were treated initially with aggressive topical steroids. Eight of the 10 eyes were receiving topical steroids at the time of presentation. The average time of presentation was 17 days after LASIK (range, 7-34). Elevated intraocular pressure was noted on average 28 days after presentation (range, 8-69). Lamellar inflammation was exacerbated by topical steroids. Resolution of the interface inflammation did not occur until intraocular pressure was controlled.

CONCLUSIONS

This case series describes a clinically distinct form of interface inflammation that presents late and is associated with elevated intraocular pressure. The lamellar inflammation was refractory to topical steroids and only resolved when pressure was controlled. These findings suggest that elevated intraocular pressure can contribute to interface inflammation. Postoperative assessment of intraocular pressure is essential in patients presenting with flap inflammation.

Incidence and outcomes of lasik with diffuse lamellar keratitis treated with topical and oral corticosteroids

PURPOSE

To analyze the incidence and clinical outcomes of patients developing diffuse lamellar keratitis (DLK) after laser in situ keratomileusis (LASIK) treated with topical and oral corticosteroids.

SETTING

Oregon Eye Institute, Eugene, Oregon, USA.

METHODS

A retrospective analysis of the last consecutive 1000 LASIK cases was performed. Eyes developing stage 3 DLK or at risk for progressing to stage 3 were treated with a combination of high-dose prednisolone acetate 1% and oral prednisone and evaluated for corneal scarring, loss of best spectacle-corrected visual acuity (BSCVA), and deviation from the intended refractive outcome.

RESULTS

Diffuse lamellar keratitis developed in 40 eyes (4%). It progressed to stage 3 in 7 eyes (17%). Oral and topical steroids were used in 22 eyes (55%). The mean variation from the desired refractive outcome was 0.14 diopter +/- 0.53 (SD). There were no instances of corneal scarring or permanent loss of BSCVA. No eye had interface irrigation.

CONCLUSIONS

Treatment of severe DLK with high-dose topical and oral corticosteroids produced excellent results without flap lifting and interface irrigation.