Bilateral Thermal Keratopathy Due to Plasma Skin Regeneration

A 40-year-old woman underwent periocular plasma skin regeneration, a cosmetic treatment for periorbital rejuvenation. She subsequently developed bilateral thermal keratitis, manifesting as blurred vision, irritation, and redness, with a vision decrease to 20/60 and 20/50 in her OD and OS, respectively. Examination demonstrated bilateral large, irregular corneal epithelial defects and edema, necessitating treatment with amniotic membrane grafts, bandage contact lenses, and hypertonic saline. One year posttreatment, her visual acuity improved to 20/20 and 20/25, albeit with ongoing symptomatic dryness and bilateral anterior stromal haze. This case, as only the second reported instance of ocular damage from periocular plasma skin regeneration, underscores the need for heightened awareness of potential ocular complications following plasma skin regeneration and reinforces the importance of protective measures during periocular procedures.

Risk of Keratitis and Keratopathy in Hidradenitis Suppurativa Patients: A Global Federated Health Network Analysis

BACKGROUND/AIM

Hidradenitis suppurativa (HS) is linked to immune dysregulation and systemic inflammation. While previous studies indicate a higher prevalence of ocular manifestations in HS, the specific risk of keratopathy and keratitis remains unclear. The primary aim of this study was to assess the risk of keratitis and keratopathy in individuals with HS.

PATIENTS AND METHODS

In this retrospective cohort study conducted with data from the TriNetX database, 53,716 patients with HS were matched to an equivalent number of non-HS controls using propensity score matching. The study covered the period from January 1st, 2005, to December 31st, 2017. Hazard ratios and their respective 95% confidence intervals (CIs), were computed to evaluate the occurrences of keratitis and keratopathy over a 5-year duration in patients with HS, compared to non-HS controls.

RESULTS

HS was associated with a 1.52 times higher risk of keratitis over a 5-year period (95%CI=1.24-1.86) and a 1.47 times higher risk of keratopathy (95%CI=1.18-1.84). These risks remained consistent in sensitivity analyses. The elevated risk of keratitis was observed across both sexes. However, the risk of keratopathy was significantly higher in women with HS (HR=1.61, 95%CI=1.24-2.10) and individuals aged 18-64 years (HR=1.32, 95%CI=1.04-1.68).

CONCLUSION

HS was linked to an elevated risk of both keratitis and keratopathy over a 5-year period. Ophthalmologic manifestations are recommended to be considered in HS standard care.

[PHOTOKERATITIS AS RESULT OF DOMESTIC EXPOSURE TO ULTRAVIOLET-C (UVC) LIGHT]

INTRODUCTION

During the global outbreak of coronavirus disease 2019 pandemic, people sought ways to disinfect their domestic and public surroundings. One of the sanitation options included the usage of ultraviolet-C (UVC) lamps since UVC radiation has been shown to effectively inactivate the SARS-Coronavirus. UVC radiation may also be effective against the SARS-CoV-2 virus. Here we report four cases of bilateral photokeratitis due to the improper usage of UV lamps during the first outbreak of COVID-19 in Israel.

METHODS

We collected 4 case reports from patients who were diagnosed with bilateral photokeratitis due to improper usage of UV lamps in their domestic environment from May to December 2020 during the first outbreak of COVID-19 in Israel.

RESULTS

A total of four patients presented with signs and symptoms of bilateral photokeratitis after exposure to UV lamps.

DISCUSSION

Acute exposure of UVC to the cornea may cause "burns", known as photokeratitis. The signs of photokeratitis usually appear a few hours after the exposure. Precautious steps to educate the population must include using protective eyewear in any exposure to UV light and avoiding the use of germicidal lamps in public locations with exposure to the population.

Applications of photodynamic therapy in keratitis

Keratitis is corneal inflammatory disease which may be caused by several reason such as an injury, allergy, as well as a microbial infection. Besides these, overexposure to ultraviolet light and unhygienic practice of contact lenses are also associated with keratitis. Based on the cause of keratitis, different lines of treatments are recommended. Photodynamic therapy is a promising approach that utilizes light activated compounds to instigate either killing or healing mechanism to treat various diseases including both communicable and non-communicable diseases. This review focuses on clinically-important patent applications and the recent literature for the use of photodynamic therapy against keratitis.

Bedside assessment of ophthalmic manifestations in neurocritical care: A study in Southern India

PURPOSE

This study aimed to investigate the incidence of Ocular Surface Disorders (OSDs), including Dry Eye Disease, Chemosis, and Exposure Keratitis, among patients admitted to the Neurocritical Care Unit (NCC). Additionally, we sought to assess the correlation between these OSDs, the length of hospitalization at NCC, and the Glasgow Coma Score (GCS). The heightened risk of OSD development in the NCC environment, coupled with pre-existing neurological impairments, can lead to conditions like dry eye disease, chemosis, corneal abrasions, and infectious keratitis, ultimately resulting in corneal opacities and perforations that significantly impact visual acuity and overall quality of life.

METHODS

In this observational cross-sectional study, we examined the ocular health of all patients admitted to an NCC unit from February to May 2022. We assessed the presence of Conjunctivitis, chemosis, Keratitis, and Dry Eyes in relation to the duration of stay at NCC, GCS, lagophthalmos, adherence to the prescribed eye care protocol in NCC, and the use of mechanical ventilation. Our study comprised one hundred subjects over a four-month period, with a mean age of 51.92 ± 18.73 years (ranging from 17 to 89), including 70% males and 30% females (gender ratio of 2.33).

RESULTS

Our findings revealed that 26 eyes (13%) exhibited Conjunctival Hyperemia, 23 eyes (11.5%) displayed Chemosis, and severe dry eye was prevalent in 41 (20.5%) eyes. A statistically significant association was observed between GCS (p-value <0.001) and Keratitis (p-value 0.0035) with dry eyes (Chi-Square Test). Notably, the incidence of dry eyes was significantly higher among patients with a prolonged stay of ≥10 days (p-value 0.003).

CONCLUSIONS

Patients admitted to Neurocritical Care Units necessitate meticulous eye care and structured protocols to mitigate the risk of long-term ocular complications such as exposure keratitis. Given their heightened susceptibility to these conditions, proactive measures are imperative to ensure optimal ocular health among NCC patients.

[Subfamily of betaherpesviruses as a cause of epithelial and stromal keratitis]

PURPOSE

This article presents the first clinical results of intravital morphological verification of epithelial and stromal keratitis associated with betaherpesviruses.

MATERIAL AND METHODS

The study group included 12 patients (12 eyes) diagnosed with herpetic keratitis. During the initial visit to the clinic, each patient underwent a standard ophthalmological examination, as well as a number of laboratory tests: immunochemical analysis of blood, molecular diagnostics, and confocal microscopy. Histological study of the cornea was additionally performed in cases indicated for surgical treatment (2 patients).

RESULTS

According to enzyme-linked immunoelectrodiffusion essay (ELISA), acute-phase immunoglobulins of class M (Ig M) to cytomegalovirus (CMV) were detected in only one clinical case. Class G immunoglobulins (Ig G) to both CMV and human herpes virus type 6 (HHV-6) were detected in the majority of cases. Quantitative polymerase chain reaction (qPCR) revealed CMV DNA in tears (2 patients) and in saliva (4 patients). The HHV-6 genome was found in tears (2 patients) and in saliva (3 patients). According to the results of confocal microscopy, owl's eye cells were found in 8 patients of the group. Histological examination of the cornea helped identify pathognomonic cells in one case. Thus, 8 patients of the group were diagnosed with keratitis associated with the betaherpesvirus subfamily.

CONCLUSION

Results of observation of the study patients suggest the possibility of developing keratitis associated with the subfamily of betaherpesviruses with localization in the superficial layers of the cornea. Confocal microscopy can be useful for identification of pathognomonic owl's eye cells in the corneal tissues and confirmation of the diagnosis of betaherpesvirus-associated keratitis. Investigation of the etiological factor of superficial and stromal viral keratitis is important for determining the further tactics of pharmacotherapy.

A Case of Candida parapsilosis Stromal Keratitis after Descemet's Membrane Endothelial Keratoplasty: A Case Report and Review of the Literature

A 68-year-old diabetic male with Fuchs endothelial corneal dystrophy cataract underwent combined DMEK and cataract surgery of the left eye. Post-operative course was complicated by a partial graft detachment on POD 3, treated with a re-bubbling procedure. The patient subsequently developed a corneal infiltrate, cultured by aqueous sample, that was found to be C. parapsilosis. Oral fluconazole and voriconazole, topical voriconazole 1%, and amphotericin B as well as intracameral and intrastromal voriconazole and amphotericin B were employed. By post-operative day 45, symptoms and signs of DMEK stromal C. parapsilosis keratitis had resolved, and a corneal scar remained. Best corrected visual acuity, at post-operative month 4, was 20/25-2 without correction. Post-DMEK fungal stromal keratitis is a rare post-operative complication. We present a case of C. parapsilosis DMEK stromal keratitis and describe diagnostic and therapeutic modalities that allowed for resolution of the infection, without explantation of the patient's graft, and preservation of visual acuity.

Neurotrophic Keratopathy After Slow Coagulation Transscleral Cyclophotocoagulation

PURPOSE

Decreased corneal sensation and subsequent neurotrophic keratopathy (NK) is an uncommon complication after transscleral cyclophotocoagulation (TSCPC). Post-TSCPC NK has been rarely reported in the literature, predominantly after traditional, "pop technique" continuous-wave TSCPC or micropulse CPC. The authors report the first case series of NK after slow-coagulation TSCPC (SC-TSCPC).

METHODS

This was a respective chart review of patients who developed NK after SC-TSCPC. The collected data included demographic data, type of glaucoma, risk factors for corneal anesthesia in addition to the number of laser spots, and the extent of the treated area.

RESULTS

Four eyes experienced NK after SC-TSCPC. The median time for the development of NK was 4 weeks. At the final visit, 2 patients had a resolution of NK, 1 had a persistent corneal ulcer, and 1 had worsening NK and corneal perforation.

CONCLUSIONS

NK is a rare but a vision-threatening complication that can develop after SC-TSCPC in patients with risk factors for decreased corneal sensation. Early diagnosis and proper management are crucial to reducing the risk of vision loss and improving the prognosis of these cases.

Thygeson's superficial punctate keratitis in children

OBJECTIVE

To describe the first paediatric case series of Thygesons' superficial punctate keratitis (TSPK) with management outcomes.

METHODS

A retrospective chart review was done for all children either diagnosed at initial presentation or referred with TSPK from 01/2012 to 08/2021 at a tertiary children's hospital. Records were assessed for signs, symptoms, diagnosis, steroid and cyclosporine 0.05% use. The main outcome measures were visual acuity, treatment response and total steroid exposure.

RESULTS

Fifteen children (7 females), mean age at presentation 8 ± 4 years were included. All had bilateral disease and a BCVA of >20/40 in the better eye. All patients received topical fluorometholone 0.1%, (FML) initially. 80% had a good response to FML. Corneal scraping was done to exclude infectious causes in four cases due to poor initial response or clinical suspicion. All 4 needed EUA for scraping and anterior segment OCT, after which 2 had molecularly confirmed TGFBI-related stromal dystrophy. For the rest, slow steroid taper was done every 4-6 weeks and recurrences were treated by increasing steroid frequency. Cyclosporine 0.05% was started in nine patients (69%), 8 ± 6 months after initial presentation. The decrease in total steroid exposure per week after starting cyclosporine was statistically significant (p < 0.05).

CONCLUSION

Children with TSPK respond quickly to steroids, however, recurrences are common, necessitating a slow taper. Non-response to steroid needs careful reconsideration of the diagnosis and may necessitate the use of an EUA. Using cyclosporine 0.05% reduces the total steroid exposure in TSPK.

Bilateral interstitial keratitis following COVID-19: a case report

BACKGROUND

Although the primary target of severe acute respiratory syndrome coronavirus 2 is the respiratory tract, the expression of the angiotensin-converting enzyme 2 receptor in other tissues facilitates viral entry in others parts of the body, including ocular structures. Ocular manifestations may occur before, during, or after systemic infection.

CASE PRESENTATION

We report the case of a 60-year-old male who presented with bilateral interstitial keratitis after the onset of COVID-19, with ocular symptoms starting within 7 days after systemic symptoms. Laboratory investigation did not identify any alternative etiology for his disease, although the possibility of Epstein-Barr virus or herpes simpex virus could not be definitively ruled out. The patient had already developed significant corneal scarring and visual debilitation by the time topical steroids were initiated, and his final corrected visual acuity with rigid gas permeable contact lenses was 20/50 and 20/80 in the right and left eye, respectively.

CONCLUSIONS

The involvement of ocular tissue by the virus can lead to permanent sequelae such as severe visual loss, and clinicians should be aware of and recognize ophthalmic manifestations of this disease to prompt early intervention.

Post-laser refractive surgery keratitis: A concise narrative review

Laser refractive surgery (LRS) is a specialized surgical discipline within ophthalmology that focuses on vision correction via laser techniques. LRS requires a high rate of accuracy and exactitude to improve the visual outcome and minimize complications, which may lead to delayed visual recovery. Keratitis, either infectious or noninfectious, is a post-LRS complication that requires early diagnosis and proper interventional measures. In this narrative review, we summarize different aspects of keratitis following LRS. This literature review aims to provide a thorough understanding of the causes of post-LRS infectious keratitis and its appropriate management for successful outcomes.

Clinical and in vivo confocal microscopy characteristics of Candida keratitis following keratoplasty

BACKGROUND

We present six patients who developed Candida keratitis postoperatively. The clinical features, diagnostic testing including in vivo confocal microscopy, and outcomes are presented.

METHODS

Six patients who developed Candida keratitis following penetrating and endothelial keratoplasty, were referred to Tianjin Medical University Eye Hospital between 2018 to 2021.The diagnosis was established following cultures of either corneal scraping or biopsy. In vivo confocal microscopy examination was also performed to confirm the diagnosis and characterize the morphology, distribution and the depth of Candida spp. All patients were treated with topical voriconazole (VCZ) 1% and natamycin (NTM) 5%. Patients with mid/deep stromal keratitis or interface infection were treated additionally with intrastromal or interface VCZ irrigation (0.05 mg/0.1mL).

RESULTS

The cultures of corneal scrapings (4 cases) or biopsies (2 cases) were all positive for Candida spp. In vivo confocal microscopy examination was positive for fungal elements in five of the six patients. The infection resolved in five of the six patients. The patients' final uncorrected visual acuity (UCVA) ranged from hand movements (HM) to 20/80.

CONCLUSION

In vivo confocal microscopy is a useful non-invasive clinical technique for confirming the diagnosis of Candida keratitis. Intrastromal and interface irrigated VCZ injections are effective treatment options.

Recurrent Filamentous Fungal Keratitis Caused When the Primarily Selected Graft Diameter was Too Small

PURPOSE

To establish the importance of using a sufficiently large corneal graft in primary penetrating keratoplasty in order to prevent recurrence of fungal keratitis.

OBERSERVATIONS

A 58-year-old female patient underwent emergency penetrating keratoplasty (diameter 7.0 mm, double running suture) for therapy-resistant fungal keratitis (Fusarium solani) at an external eye clinic. Despite intensive antifungal therapy, new fungal infiltrates appeared in the host cornea after a few days. The patient was referred to our department for further treatment. On first presentation, circular infiltrates were seen around the corneal graft with anterior chamber involvement and therapy-resistant hypopyon. We performed an emergency penetrating repeat keratoplasty (diameter of 13.0 mm, 32 interrupted sutures) combined with anterior chamber lavage and intracameral and intrastromal drug injection.

CONCLUSION AND IMPORTANCE

Fungal keratitis sometimes has a frustrating clinical course. Therefore, early diagnosis with effective therapy initiation is of the utmost importance. In cases of penetrating keratoplasty, optimal planning and timing (before anterior chamber involvement) should be provided. Sufficient safety distance must be ensured in the choice of graft diameter, fixation with multiple interrupted sutures, and anterior chamber lavage, as well as intracameral and intrastromal drug administration. Incomplete excision carries a risk of recurrence and endophthalmitis in the course. Close postoperative control is necessary to detect early recurrences.

Infectious Keratitis After Keratorefractive Surgery: Update and Review of the Literature

OBJECTIVES

To summarize the clinical manifestations, microbiological profile, treatment, and prognosis of corneal infections after different keratorefractive surgery.

METHODS

To obtain relevant studies, English-language databases, including PubMed, Ovid Embase, Web of Science, and CLNAHL, were searched from January 1979 to March 2022. The fundamentals of the literature, clinical characteristics, pathogens, and treatments were retrieved for each included article.

RESULTS

Eighty-four studies involving 306 infectious eyes were included in this review. Risk factors of potential infection included a history of blepharitis, contact lens usage, and contaminated surgical instruments. The mean onset time was 22.9±38.7 days (range: 1 day to 3 years). The most common organism isolated from infectious keratitis after keratorefractive surgery were Staphylococcus aureus , followed by Mycobacterium and coagulase-negative Staphylococcus . Most of the infections after refractive procedures were sensitive to medical treatment alone, and the ultimate best-corrected visual acuity after medical treatment was as follows: 20/20 or better in 82 cases (37.0%), 20/40 or better in 170 cases (76.5%), and worse than 20/40 in 52 cases (23.5%). Surgical interventions including flap lift, flap amputation, ring removal, and keratoplasty were performed in 120 eyes (44.5%).

CONCLUSIONS

Most infections after keratorefractive surgery occur within a week, whereas more than half of the cases after laser-assisted in situ keratomileusis happen after about a month. Gram-positive cocci and mycobacterium are the most common isolates. Infections after LASIK, intracorneal ring (ICR) implantation, and small incision lenticule extraction, which primarily occur between the cornea layers, require irrigation of the tunnels or pocket with antibiotics.

Therapeutic contact lens-related infection by a novel pathogenic fungus Coniochaeta hoffmannii-a case report

This study aims to report a rare instance of corneal decompensation brought on by Coniochaeta hoffmannii fungus invasion of a bandage contact lens (BCL). A 71-year-old man with pseudophakic bullous keratopathy (PBK) had BCL treatment for four months to symptomatically reduce pain and itching in his right eye. However, the patient unexpectedly lost his vision. The slit-lamp examination revealed an edematous cornea; the extensive direct inspection raised suspicion of BCL. For morphological characterization, the BCL extracted was inoculated onto 5% sheep blood agar and PDA. By Sanger sequencing method the isolate's genomic DNA was molecularly identified as C. hoffmannii.

Incidence of Corneal Adverse Events in Children Wearing Soft Contact Lenses

OBJECTIVES

There is increasing interest in fitting children with soft contact lenses, in part due to the increase in prescribing of designs to slow the progression of myopia. This literature review summarizes large prospective and retrospective studies that include data on the incidence of microbial keratitis and corneal infiltrative events (CIEs) in children wearing soft contact lenses.

METHODS

Peer-reviewed prospective and retrospective studies that report contact lens-related complications in children with at least one year of wear and at least 100 patient years of wear were identified.

RESULTS

Seven prospective studies published between 2004 and 2022 were identified representing 3,752 patient years of wear in 1,756 children, nearly all of whom were fitted at age 12 years or younger. Collectively, they report one case of microbial keratitis and 53 CIEs, of which 16 were classified as symptomatic. The overall incidence of microbial keratitis was 2.7 per 10,000 patient years (95% CI: 0.5-15), and the incidence of symptomatic CIEs was 42 per 10,000 patient years (95% CI: 26-69). Two retrospective studies were identified representing 2,545 patient years of wear in 1,025 children, fitted at age 12 years or younger. One study reports two cases of microbial keratitis giving an incidence of 9.4 per 10,000 patient years (95% CI: 0.5-15).

CONCLUSIONS

Accurate classification of CIEs is challenging, particularly in retrospective studies. The incidence of microbial keratitis in children wearing soft lenses is no higher than in adults, and the incidence of CIEs seems to be markedly lower.

The epidemiology of infectious keratitis

Infectious keratitis is a rare but potentially severe sight-threatening disease, associated with considerable societal burden, cost and morbidity. This review summarises the most recent evidence for the incidence, risk factors and impact of disease, all of which vary widely according to region, access to health care, socioeconomic and environmental factors, predisposing conditions and causative organisms. The frequency and societal impact of infectious keratitis are significantly higher in low-income countries. In non-viral infectious keratitis, bacterial causes predominate in most regions. Fungi, particularly linked with agricultural trauma, are more frequently associated with infectious keratitis in low-income regions, particularly in India and certain African countries. The disease impact is compounded by poverty and limited access to services and treatment. Early diagnosis, access to appropriate treatment, prophylaxis in ocular trauma, availability of eye protection, awareness of risk factors may be associated with reduced disease severity and vision loss. Evidence for the incidence and burden of disease is lacking in certain regions and well-designed epidemiological studies to identify independent risk factors for the disease and those associated with more severe outcomes may better identify causation and guide resource allocation and preventative strategies.

Survey-Based Estimation of Corneal Complications Associated with Scleral Lens Wear

ABSTRACT

The benefits of scleral lens (SL) wear have been described in cross-sectional and retrospective studies; however, the frequency of complications associated with SL wear has not, to the best of our knowledge, been determined. From a survey of SL practitioners, we estimated the period prevalence over 1 year of corneal complications that required SL wearers to discontinue lens wear. In a sample of 72,605 wearers, SL wear was discontinued for the following complications: corneal edema, 1.2%; corneal neovascularization, 0.53%; microbial keratitis, 0.45%; and limbal stem cell deficiency, 0.20%. This study design allowed for calculation of period prevalence of these complications rather than complication incidence rates. Information presented in this report may be useful in clinical decision-making and for future study design.

Post photorefractive keratectomy (PRK) infectious keratitis; six-year experience of a tertiary eye hospital

BACKGROUND/OBJECTIVES

As an essential development in the new century, surface ablation procedures have attracted increasing attention. There exists a concern regarding the risk of infectious keratitis. Hence, we aimed to investigate the rate and predisposing factors of infectious keratitis after photorefractive keratectomy (PRK).

SUBJECTS/METHODS

This retrospective study was designed in two phases. First, the rate of post-PRK keratitis of Farabi Eye Hospital was investigated. In other words, the targeted population was the patients who developed keratitis after performing procedure at Farabi Eye Hospital. In the second phase, all the patients with the diagnosis of post-PRK keratitis were studied regardless of the centre where surgery was performed. Patients with the diagnosis of infectious keratitis between 2014 and 2020 were enrolled and following information was analyzed: demographics, presentation time after surgery, perioperative medications, culture results, risk factors, medical treatment, complications, and final visual acuity.

RESULTS

The total number of PRK procedures in our centre was 24,986 (13,253 patients), in which 6 eyes of 5 patients developed keratitis. Beside these 5 patients, 24 referred patients (24 eyes) from the other centres were enrolled. Finally, a total number of 29 patients (30 eyes) were included. Our analysis revealed that manipulation of contact lens, dry eye, and blepharitis were the essential predisposing factors for keratitis development.

CONCLUSION

The overall post-PRK keratitis occurrence rate of our study was 0.02%. Our observation highlighted the importance of preoperative examination and treatment of the lids and dry eye disease.

Neurotrophic Keratopathy After Herpes Zoster Ophthalmicus

PURPOSE

The aim of this study was to describe risk factors for neurotrophic keratopathy (NK) after herpes zoster ophthalmicus (HZO).

METHODS

This study was a retrospective review of all patients seen at the Auckland District Health Board with HZO from 2006 through 2016. Cox proportional hazards analysis was performed to examine time to development of neurotrophic keratitis.

RESULTS

Eight hundred sixty-nine patients were included in the study with a median follow-up of 6.3 years (5504.4 patient-years). The median age was 65.5 years (interquartile range 52.9-75.4), and 456 subjects (52.5%) were male. NK developed in 58 patients (6.7%), with the highest hazard 1 to 2 years after onset of HZO. On univariate analysis, age, White ethnicity, best-corrected visual acuity (BCVA) at presentation, intraocular pressure, corneal involvement, uveitis, and number of recurrences were associated with increased risk of NK. On multivariate analysis, the following factors were significant: age (hazard ratio [HR] = 1.03; P = 0.021), White ethnicity (HR = 3.18; P = 0.015), BCVA (HR = 1.81; P = 0.026), uveitis (HR = 3.77; P = 0.001), and recurrence (HR = 1.34; P < 0.001). Vision loss (BCVA ≤6/15) was more frequent in subjects with NK (65.5% vs. 16.3%, P < 0.001).

CONCLUSIONS

NK is a relatively common and serious complication of HZO and occurs more frequently in older White individuals, those with poor visual acuity at presentation, and those with uveitis. Vision loss occurs in approximately two-thirds of patients.

Topical Review: Contact Lens Eye Health and Safety Considerations in Government Policy Development

SIGNIFICANCE

As new federal or state policies are introduced in the United States to shape the evolving contact lens market, it has never been more important to amplify the importance of patient health and safety during contact lens wear and promote the value of the eye care professional-patient relationship.Within the United States, contact lenses are regulated by the Food and Drug Administration as class II or III medical devices that require additional regulatory and professional oversight to keep consumers safe. The contact lens market and broader eye health landscape are rapidly changing. Recently, the U.S. Federal Trade Commission finalized its 10-year review of the Contact Lens Rule, implementing new policies that will shape the contact lens market in the United States for years to come. The purpose of this clinical perspective was to compile and review key data regarding contact lens-related adverse events, including their economic impact on the health care system, to inform government policy development. Although contact lenses provide many benefits to the wearer, a variety of complications can occur ranging from asymptomatic events or mild discomfort to severe sight-threatening adverse events such as microbial keratitis. Patients who do not routinely visit their eye care professional or do not receive the lenses prescribed to them are at a greater risk of contact lens-related adverse events. Nearly 1 million people in the United States experience ocular infections or inflammation annually, resulting in significant health care costs. The economic burden of contact lens-related microbial keratitis in the United States has been estimated to be approximately $175 million annually. The importance of eye care professional oversight of contact lens wear cannot be emphasized enough to key stakeholders, including lawmakers, government regulators, contact lens manufacturers and distributors, and the broader eye health community.

Oleander-Associated Keratitis and Uveitis

PURPOSE

Oleander is a poisonous plant with extensively documented systemic side effects; however, oleander's ophthalmic side effects have not been detailed in the literature. We report a case of oleander-associated keratitis with subsequent corneal edema and anterior uveitis.

METHODS

This is a case report and review of relevant literature.

RESULTS

A 58-year-old woman presented with large corneal epithelial defect after being struck in the eye with an oleander leaf. Despite treatment with topical moxifloxacin, she developed severe corneal edema and anterior uveitis. A diagnosis of oleander-associated ocular inflammation with secondary corneal edema was made, given the temporal relationship, and treatment was initiated with topical prednisolone and cyclopentolate. However, the corneal edema and inflammation continued to progress until oral prednisone and topical difluprednate were initiated. Visual acuity, anterior uveitis, and corneal edema significantly improved with aggressive immunomodulation. Follow-up at 1 month confirmed complete recovery of symptoms, corneal edema and anterior uveitis.

CONCLUSIONS

Severe corneal edema and anterior uveitis can be associated with oleander exposure. Aggressive treatment with oral and topical steroids may be required without persistent sequelae at the 5-month follow-up. Ophthalmologists should consider this inflammatory reaction if patients experience ocular exposure to oleander.

Characteristics of the ocular surface in neurotrophic keratitis induced by trigeminal nerve injury following neurosurgery

Purpose

To analyse and quantify ocular surface parameters in patients with unilateral neurotrophic keratitis (NK) induced by trigeminal nerve injury post-neurosurgery.

Methods

The study included 26 unilateral NK patients who had undergone neurosurgery, and 20 matched normal controls. Demographic and clinical characteristics of all participants were collected and analysed. Slit-lamp examination, Cochet–Bonnet aesthesiometry, Keratograph 5 M, and LipiView interferometer were performed on both eyes of 17 mild NK patients. For nine moderate/severe NK patients, sub-basal nerve density was measured by in vivo confocal microscopy.

Results

Of the 26 patients, nine had acoustic neuroma, nine had trigeminal neuralgia, and eight had neoplasms. Facial nerve paralysis was observed in one of the 17 mild NK eyes (5.9%) and seven of the nine moderate/severe NK eyes (77.8%). Compared to contralateral and normal control eyes, 26 NK eyes showed significantly reduced sensitivity in five corneal regions (P < 0.05). Corneal sensitivity in moderate/severe NK eyes was significantly lower than in mild NK eyes (P < 0.05). Moderate/severe NK eyes had poor visual acuity, and their sub-basal nerve density was lower than that of the controls. The onset of the moderate/severe NK was from 0.5 to 24 months (median [Q1, Q3], 1 [0.5, 2.5] months) after neurosurgery. For the mild NK eyes, the number of total blinks, the first non-invasive tear breakup time (NITBUT) and average NITBUT were significantly lower than contralateral and normal control eyes (P < 0.05), and the number of partial blinks and partial blinking rate were significantly higher than the other two control groups (P < 0.05).

Conclusions

Patients with NK induced by trigeminal nerve injury following neurosurgery had decreased corneal sensitivity to various degrees accompanied by increased partial blinks and shortened NITBUT. The severity of NK is related to the severity of the corneal sensory impairment. Facial nerve paralysis can worsen the clinical progression of NK.

Trial registration Chinese Clinical Trial Registry (ChiCTR2100044068, Date of Registration: March 9, 2021).

[Infectious keratitis and corneal transplantation in a 15-year-old patient wearing contact lenses]

BACKGROUND

Soft contact lens wearing increases the risk of an infectious keratitis. A patient present with a red painfull eye, in which case a corneal erosion (coloring with fluorescein) was seen by the general practitioner. It is possible that the clinical course worsens in a few days with a corneal perforation as a result. In these cases a timely referral is necessary.

CASE

A fifteen year old soft contact lens wearing girl developed an infectious keratitis. Within a few days she developed a corneal perforation. As a result of an emergency transplantation within 24 hours the patient preserved her globe and her visual acuity recovered.

CONCLUSION

Emergency transplantations usually have a complicated course with a high risk of re-transplantation and long-term pharmacological therapy. Such an emergency transplantation is primarily performed to preserve the globe. In the Netherlands a separate pool of emergency donor transplants is available, so that a transplantation can be performed within 24 hours.

Fungal Infectious Interface Keratitis Presenting 2 Years After Descemet Membrane Endothelial Keratoplasty

PURPOSE

The purpose of this study was to describe infectious interface keratitis after Descemet membrane endothelial keratoplasty (DMEK) more than 2 years after surgery.

METHODS

A case study.

RESULTS

In this study, we report a case of fungal infectious interface keratitis occurring 2 years after uncomplicated Descemet membrane endothelial keratoplasty. The donor corneal rim culture at the time of surgery grew a single colony of Candida albicans/dubliniensis , but the patient was not treated with antifungals at that time. At the onset of clinical infection, more than 2 years postoperatively, the patient was treated with systemic antifungals and adjuvant intrastromal amphotericin-B injection. The patient subsequently required penetrating keratoplasty with ultimately well-preserved visual acuity.

CONCLUSIONS

Fungal infectious interface keratitis (IIK) is a rare complication associated with lamellar keratoplasty. Although most common in the early postoperative period, this complication can occur several years after successful transplantation. Management may require a combination of systemic and stromal antifungal therapy. However, some patients may eventually require penetrating keratoplasty for definitive treatment.

Role of corneal biopsy in the management of infectious keratitis

PURPOSE OF REVIEW

The aim of this study was to review the existing literature and investigate the role of microbiologic culture and histopathologic examination of corneal biopsies in the management of infectious keratitis.

RECENT FINDINGS

Corneal biopsy continues to be a significantly useful tool in the diagnosis and tailored management of infectious keratitis. Several techniques can be employed for tissue collection, handling and processing to optimize diagnostic yield and maximize safety, including emerging femtosecond laser-assisted biopsy.

SUMMARY

Corneal opacities represent a significant cause of global blindness, and infectious keratitis is the most common cause. Organism identification in progressive infectious keratitis is essential for proper management. However, microbiological culture alone has a high rate of false-negative results. Records from the Bascom Palmer Eye Institute were retrospectively searched for patients between 1 January 2015, and 31 December 2019, who underwent corneal biopsy, therapeutic keratoplasty or endothelial graft removal for infectious keratitis and had specimens bisected and submitted for evaluation with both microbiologic culture and histopathologic examination. Detection of bacteria, fungus and mycobacteria was not statistically different between culture and histopathology. Microbiology and histopathology are complementary methods for the identification of causative microorganisms in corneal specimens with presumed infectious keratitis.

Mechanisms Underlying Contact Lens-Related Keratitis Caused by Pseudomonas aeruginosa

ABSTRACT

Infectious keratitis is a severe complication associated with contact lens (CL) wear, and can progress rapidly with suppurative infiltration, resulting in the loss of vision. Contact lens wearers with poor and improper care are susceptible to develop infectious keratitis. Gram-negative bacilli such as Pseudomonas aeruginosa, have an ability to form biofilms on CL cases and CLs. Moreover, P. aeruginosa has various virulence factors such as type III secretion system (TTSS) which is an important factor for pathogenicity in keratitis. The effector proteins of TTSS have been identified, namely ExoU, ExoS, ExoT, and ExoY. Pseudomonas aeruginosa strains with ExoU show resistance to disinfection. The strains isolated from CL-related keratitis have higher ExoU gene positivity. Expression of elastase and swarming motility of P. aeruginosa isolates significantly correlates with focus size of keratitis. In addition to education of lens care for the CL wearer, development of CL cleaning solutions targeting suppression of virulence factors are needed for prevention of CL-related keratitis in the future.

Severe Ocular Complications Associated With Wearing of Contact Lens in Japan

OBJECTIVES

To examine the severe ocular complications associated with contact lens wearing in Japan.

METHOD

A questionnaire was sent to 964 ophthalmologist training facilities inquiring for cases of contact lens-associated complications from April 2016 to March 2018. The inclusion criteria were as follows: (1) corrected distance visual acuity ≤0.1 decimal after treatment for 3 months, (2) corneal perforation observed during follow-up, and (3) requiring surgery. A secondary analysis was conducted, inquiring for further information on the type of contact lens, clinical manifestations, and course of treatment.

RESULTS

Forty-two patients with infectious keratitis met the inclusion criteria. Eight patients were users of rigid gas-permeable contact lens, and 34 were users of soft contact lens. Microbiological tests were positive in 73.0%. The organisms isolated in microbiological culture were bacteria in 11 patients (Pseudomonas aeruginosa in 9 patients), fungi in 2 patients, and Acanthamoeba in 14 patients. Ten patients were treated with local antibiotics, 11 with a combination of systemic antibiotics, and 21 with a combination of surgical approaches, including 13 with corneal transplantation.

CONCLUSIONS

The major cause of serious contact lens-associated ocular complications was microbial keratitis, and P. aeruginosa and Acanthamoeba were the major pathogens in Japan.

Human Adenovirus Species D Interactions with Corneal Stromal Cells

Notable among the many communicable agents known to infect the human cornea is the human adenovirus, with less than ten adenoviruses having corneal tropism out of more than 100 known types. The syndrome of epidemic keratoconjunctivitis (EKC), caused principally by human adenovirus, presents acutely with epithelial keratitis, and later with stromal keratitis that can be chronic and recurrent. In this review, we discuss the current state of knowledge regarding the molecular biology of adenovirus infection of corneal stromal cells, among which the fibroblast-like keratocyte is the most predominant, in order to elucidate basic pathophysiologic mechanisms of stromal keratitis in the human patient with EKC.

Adjunctive Thymosin Beta-4 Treatment Influences MΦ Effector Cell Function to Improve Disease Outcome in Pseudomonas aeruginosa-Induced Keratitis

Our previous work has shown that topical thymosin beta 4 (Tβ4) as an adjunct to ciprofloxacin treatment reduces inflammatory mediators and inflammatory cell infiltrates (neutrophils/PMN and macrophages/MΦ) while enhancing bacterial killing and wound healing pathway activation in an experimental model of P. aeruginosa-induced keratitis. This study aimed to mechanistically examine how Tβ4 influences MΦ function in particular, leading to reduced inflammation and enhanced host defense following P. aeruginosa-induced infection of the cornea. Flow cytometry was conducted to profile the phenotype of infiltrating MΦ after infection, while generation of reactive nitrogen species and markers of efferocytosis were detected to assess functional activity. In vitro studies were performed utilizing RAW 264.7 cells to verify and extend the in vivo findings. Tβ4 treatment decreases MΦ infiltration and regulates the activation state in response to infected corneas. MΦ functional data demonstrated that the adjunctive Tβ4 treatment group significantly downregulated reactive nitrogen species (RNS) production and efferocytotic activity. In addition, the in vitro studies showed that both Tβ4 alone and adjunctive Tβ4 treatment influenced MΦ cellular function following LPS stimulation. Collectively, these data provide further evidence that adjunctive Tβ4 + ciprofloxacin treatment offers a more efficacious option for treating bacterial keratitis. Not only does the adjunctive therapy address both the infectious pathogen and corneal wound healing response, but it also influences MΦ infiltration, activation, and function, as revealed by the current study.

Pediatric Microbial Keratitis With Overnight Orthokeratology in Russia

OBJECTIVES

To estimate the incidence of microbial keratitis in children wearing overnight orthokeratology lenses in Moscow, Russia.

METHODS

To estimate the number of children wearing overnight orthokeratology lenses in 2018, 1,368 patient records from 13 Doctors Lens clinics were selected at random and extrapolated to the entire patient base. To identify cases of microbial keratitis, all episodes of infiltrative keratitis from Morozovskaya City Children's Clinical Hospital in 2018 were recorded and adjudicated by three experienced ophthalmologists. Incidence was calculated as the number of cases divided by the estimated number of wearers.

RESULTS

There were 23,049 overnight orthokeratology fits between 2010 and 2018. Among the 1,368 records surveyed, 1,078 (79%) were younger than 18 years at initial fitting. Based on a 7% or 10% annual discontinuation rate, the estimated number of children wearing lenses in 2018 was 10,307 or 9,422, respectively. During 2018, there were 139 cases of corneal infiltrative keratitis in children and 45 were adjudicated as microbial keratitis (32%). Of these, 20 cases were associated with contact lens wear (44%): 15 soft lens wearers (33%) and 5 overnight orthokeratology wearers (11%). Based on the 5 cases and assuming a 7% or 10% discontinuation rate, the annual incidence is 4.9 (95% confidence interval[CI]: 2.1-11.4) or 5.3 (95% CI: 2.3-12.4) per 10,000 patient years.

CONCLUSION

The incidence of microbial keratitis in children wearing overnight orthokeratology is lower than a previous United States study and similar to rates associated with use of daily wear soft contact lenses.

Clinical Applications of In Vivo Confocal Microscopy in Keratorefractive Surgery

PURPOSE

To review the contribution of in vivo confocal microscopy (IVCM) to the understanding of corneal wound healing following refractive surgery, and its role in the diagnosis and management of complications arising from keratorefractive procedures.

METHODS

Review of the basic science and clinical literature relating to the study of keratorefractive surgical procedures using IVCM.

RESULTS

Extensive research using IVCM has generated a comprehensive understanding of tissue responses after corneal refractive surgery. Epithelial thickness and stromal keratocyte density can be quantified postoperatively and studied longitudinally. Corneal nerve loss and subsequent reinnervation has been characterized and differs significantly between laser refractive techniques. IVCM has also been used to study complications arising from postoperative inflammation (diffuse lamellar keratitis, central toxic keratopathy, ring keratitis, and ectasia), infection (microbial keratitis), and neuropathy (dry eye and neuralgia). This imaging technique can have a critical role in the diagnosis of these complications and subsequent monitoring of treatment response. Manual processing of IVCM images is time-consuming and there may be significant interobserver and intraobserver variability with poor repeatability. However, increasing automation and the use of artificial intelligence is improving the speed and accuracy of image analysis.

CONCLUSIONS

IVCM has historically been confined to a research setting because image capture and subsequent processing was extremely labor intensive. However, advances in both hardware and software capabilities promise to allow the use of IVCM in routine clinical practice. Real-time evaluation of the cornea at a cellular level will be particularly useful in patients with inflammatory, infectious, or neuropathic complications of keratorefractive surgery. [J Refract Surg. 2021;37(7):493-503.].

Diffuse Lamellar Keratitis in a Patient Undergoing Collagen Corneal Cross-Linking 18 Years After Laser In Situ Keratomileusis Surgery

PURPOSE

To report a case of diffuse lamellar keratitis (DLK) after corneal collagen cross-linking in an eye with a remote history of laser in situ keratomileusis (LASIK) surgery.

METHODS

This is a case report and literature review.

RESULTS

This report describes the development of unilateral stage IV DLK in a patient who underwent bilateral corneal cross-linking for corneal ectasia 18 years after LASIK surgery. The patient was treated with high-dose topical steroids that were tapered over 1 month and multiple flap lifts. The ultimate best-corrected visual outcome was 20/60.

CONCLUSIONS

DLK is a potential sight-threatening complication of refractive surgery that can occur at any time in the postoperative period, even years after the procedure. Undergoing a subsequent corneal procedure that may disrupt or promote inflammation within the surgical flap-stromal interface, such as corneal collagen cross-linking, is a recognized risk factor for the development of DLK. This case suggests that patients with any history of LASIK surgery undergoing corneal cross-linking or other lamellar corneal surgeries may benefit from closer follow-up (eg, daily) than patients with no history of LASIK.

NEUROTROPHIC KERATOPATHY AFTER RETINAL DETACHMENT SURGERY COMBINED WITH ENDOLASER PHOTOCOAGULATION

PURPOSE

To report neurotrophic keratopathy after vitreoretinal surgery combined with aggressive photocoagulation.

METHODS

We report a series of three cases with neurotrophic keratopathy after pars plana vitrectomy combined with endolaser photocoagulation.

RESULTS

Three patients who had pars plana vitrectomy with different indications were identified. On follow-up, all patients were diagnosed with neurotrophic keratopathy. Two of the patients underwent amniotic membrane transplantation for the treatment of resistant neurotrophic corneal ulcers.

CONCLUSION

Neurotrophic keratopathy may occur after pars plana vitrectomy. The possible mechanism is long ciliary nerve damage related to the extensive endolaser photocoagulation.

Increased photokeratitis during the coronavirus disease 2019 pandemic: Clinical and epidemiological features and preventive measures

An increased incidence of photokeratitis has occurred during the coronavirus disease 2019 (COVID-19) pandemic due to improper and unprotected use of ultraviolet lamps. Here, we summarize the clinical and epidemiological features of this increased incidence of photokeratitis and share advice in using health education to prevent it.We collected data from patients diagnosed with photokeratitis from October 7, 2019 to December 1, 2019, and from February 17, 2020 to April 12, 2020, and compared the frequency of onset, site of ultraviolet radiation (UVR) exposure, reason for exposure, exposure time, and recovery time. We also implemented and evaluated multiple measures of public health education to prevent increased disease.After the COVID-19 outbreak, the frequency of onset of photokeratitis increased significantly, especially among young women. The main reason for UVR exposure changed from welding to disinfection. The incidence sites varied, and the exposure time was longer. As a result, patients needed a longer time to recover. Positive health education was an useful and convenient measure to prevent the disease.While the COVID-19 pandemic is ongoing, more attention should be paid to public health and implement positive measures to prevent photokeratitis.

Pseudomonas aeruginosa-induced nociceptor activation increases susceptibility to infection

We report a rapid reduction in blink reflexes during in vivo ocular Pseudomonas aeruginosa infection, which is commonly attributed and indicative of functional neuronal damage. Sensory neurons derived in vitro from trigeminal ganglia (TG) were able to directly respond to P. aeruginosa but reacted significantly less to strains of P. aeruginosa that lacked virulence factors such as pili, flagella, or a type III secretion system. These observations led us to explore the impact of neurons on the host's susceptibility to P. aeruginosa keratitis. Mice were treated with Resiniferatoxin (RTX), a potent activator of Transient Receptor Potential Vanilloid 1 (TRPV1) channels, which significantly ablated corneal sensory neurons, exhibited delayed disease progression that was exemplified with decreased bacterial corneal burdens and altered neutrophil trafficking. Sensitization to disease was due to the increased frequencies of CGRP-induced ICAM-1+ neutrophils in the infected corneas and reduced neutrophil bactericidal activities. These data showed that sensory neurons regulate corneal neutrophil responses in a tissue-specific matter affecting disease progression during P. aeruginosa keratitis. Hence, therapeutic modalities that control nociception could beneficially impact anti-infective therapy.

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.

Risk Factors for Contact Lens-Related Microbial Keratitis and Associated Vision Loss in a South Indian Population

OBJECTIVES

To identify risk factors associated with contact lens-related microbial keratitis (CL-MK) and subsequent vision loss in a south Indian population.

METHODS

A retrospective study of medical records at the LV Prasad Eye Institute in Hyderabad, India, of patients diagnosed with CL-MK and of controls who had no history of corneal inflammation during contact lens wear was undertaken. Variables such as demographic data, contact lens wear details, duration of the event, visual acuity, epithelial defect and infiltrate size, and microbiology of the cornea during the event were collected. Differences between cases and controls were analyzed using parametric and nonparametric tests. Logistic regression was used to calculate the odds ratio (OR) and associated 95% confidence intervals in univariate and multivariate analyses for cases vs. controls and for factors associated with vision loss.

RESULTS

One hundred sixty-seven cases of CL-MK and 153 controls were included in the analyses. Risk factors associated with the greatest increased OR for CL-related MK were: being in professional employment vs. a student (OR=3.9), disposing lenses yearly versus monthly or biweekly (OR=2.2), and any overnight wear (OR=2.8). Risk factors associated with vision loss were: high myopia (OR=3.6), severe vs. mild severity (OR=16.0), and hypopyon (OR=4.3).

CONCLUSIONS

Identification of these risk factors may help inform safe contact lens wear habits and management strategies.

Diffuse lamellar keratitis after LASIK with low-energy femtosecond laser

PURPOSE

To evaluate the incidence, evolution, and prognosis of diffuse lamellar keratitis (DLK) in a large series of laser in situ keratomileusis (LASIK) with low-energy femtosecond laser.

SETTING

Private practice, Siena, Italy.

DESIGN

Retrospective, consecutive, noncomparative case series study.

METHODS

Single-use instruments, powder-free gloves, and no corneal marking were used. Flap was created by a low-energy femtosecond laser (Ziemer Z2 and Z4).

RESULTS

A total of 37 315 eyes of 19 602 patients were reviewed. DLK was observed in 236 eyes (0.63%) of 149 patients (0.76%). Grade 1 DLK was observed in 231 eyes of 142 patients, grade 2 in 1 eye: when treated with topical steroids, they had no visual consequences. Three patients had bilateral grade 3 to 4 DLK: one of them, with bilateral grade 3, despite flap lifting and irrigation worsened to stage 4 (central stroma thinning and flattening), partially recovered in 2 years, and underwent repeat femtosecond laser-assisted LASIK for hyperopic shift in 1 eye. In all the 5 eyes that developed grade 4 DLK, corneal thickness decreased until the first month and then partially recovered; mean final tissue loss at 1 to 2 years was 35 µm. Compensatory epithelial thickening was observed.

CONCLUSIONS

DLK after low-energy femtosecond laser-assisted LASIK is rare; severe DLK (stages 3 and 4) was found in only 6 eyes (0.016%). Flap lifting and irrigation might not prevent progression. Spontaneous reformation of stromal tissue and epithelial thickening improve visual acuity in the long term; residual hyperopic shift can be corrected by repeat femtosecond laser-assisted LASIK.

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.].