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.

Bilateral Increase of Matrix Metalloproteinase-9 Expression in Tears After the Unilateral Decrease of Corneal Sensitivity.

PURPOSE: The purpose of this study is to analyze bilateral changes of matrix metalloproteinase-9 (MMP-9) expression in the tear film in patients with unilateral neurotrophic keratitis. METHODS: We included 24 eyes from 24 subjects with normal corneal sensitivity according to Cochet-Bonnet corneal esthesiometry in the control group and 25 subjects with the unilateral neurotrophic keratitis in the unilateral decrease of corneal sensitivity (UDCS) group. The expression of MMP-9 in tears was assessed using point-of-care immunoassay. The clinical parameters including meibomian gland plugging, quality of the secreted meibum, tear secretion using Schirmer I without anesthesia, and corneal erosions were evaluated among the control, affected, and contralateral unaffected eyes in the UDCS group. RESULTS: Tear MMP-9 grades in affected (2.5 ± 1.0) and contralateral eyes (2.6 ± 0.9) in the UDCS group were higher than those in control eyes (1.5 ± 0.7, P = 0.0003 and P = 0.0006, respectively). The lacrimal secretion decreased in the affected eyes but preserved in the contralateral eyes. There was no difference in corneal erosion scores between control eyes and contralateral eyes in the UDCS group. Tear MMP-9 grades in the contralateral eyes were significantly correlated with the meibum quality grades in the contralateral eyes (r = 0.525 and P = 0.025). CONCLUSIONS: Patients with the unilateral neurotrophic keratitis demonstrated a significant bilateral increase of the MMP-9 expression in the tear film as compared with controls. Despite the tearing reflex and corneal surface barrier being preserved in the unaffected contralateral eyes, it is necessary to pay attention to the possible attenuation of meibomian gland function in the opposite eyes as well.

A Hypothalamic-Controlled Neural Reflex Promotes Corneal Inflammation.

Purpose: To test whether an acute corneal injury activates a proinflammatory reflex, involving corneal sensory nerves expressing substance P (SP), the hypothalamus, and the sympathetic nervous system. Methods: C57BL6/N (wild-type [WT]) and SP-depleted B6.Cg-Tac1tm1Bbm/J (TAC1-KO) mice underwent bilateral corneal alkali burn. One group of WT mice received oxybuprocaine before alkali burn. One hour later, hypothalamic neuronal activity was assessed in vivo by magnetic resonance imaging and ex vivo by cFOS staining. Some animals were followed up for 14 days to evaluate corneal transparency and inflammation. Tyrosine hydroxylase (TH), neurokinin 1 receptor (NK1R), and neuronal nitric oxide synthase (nNOS) expression was assessed in brain sections. Sympathetic neuron activation was evaluated in the superior cervical ganglion (SCG). CD45+ leukocytes were quantified in whole-mounted corneas. Noradrenaline (NA) was evaluated in the cornea and bone marrow. Results: Alkali burn acutely induced neuronal activation in the trigeminal ganglion, paraventricular hypothalamus, and lateral hypothalamic area (PVH and LHA), which was significantly lower in TAC1-KO mice (P < 0.05). Oxybuprocaine application similarly reduced neuronal activation (P < 0.05). TAC1-KO mice showed a reduced number of cFOS+/NK1R+/TH+ presympathetic neurons (P < 0.05) paralleled by higher nNOS expression (P < 0.05) in both PVH and LHA. A decrease in activated sympathetic neurons in the SCG and NA levels in both cornea/bone marrow and reduced corneal leukocyte infiltration (P < 0.05) in TAC1-KO mice were found. Finally, 14 days after injury, TAC1-KO mice showed reduced corneal opacity and inflammation (P < 0.05). Conclusions: Our findings suggest that stimulation of corneal sensory nerves containing SP activates presympathetic neurons located in the PVH and LHA, leading to sympathetic activation, peripheral release of NA, and corneal inflammation.

Characterization and Management of Inflammatory Eye Disease in Patients with Hidradenitis Suppurativa.

Purpose: To assess the spectrum and treatment outcomes of inflammatory eye disease (IED) in subjects with hidradenitis suppurativa (HS).Methods: We conducted a single center retrospective chart review of 236 patients with HS seen for ophthalmic examination between 2013 and 2018.Results: Of 236 subjects with HS, 22 subjects (9.3%) were found to have IED. Seven of 22 subjects had more than one IED diagnosis. Anterior uveitis was the most common type of IED (40.9% of subjects with IED). Episcleritis, optic neuritis, keratitis, scleritis, intermediate and posterior uveitis, trochleitis, and dacryoadenitis were also observed. Of subjects with HS and IED, 59.1% did not have any other inflammatory or autoimmune disease that could explain the etiology of their IED. Eleven patients with IED were treated with systemic immunosuppression, with IED as the principal factor directing treatment in three patients.Conclusions: IED may be independently associated with HS and may benefit from systemic immunosuppression.

Hyaluronic Acid-Pluronic®F127-Laden Soft Contact Lenses for Corneal Epithelial Healing: In Vitro and In Vivo Studies.

Hyaluronic acid (HA) is widely used to treat various ocular diseases like dry eye syndrome, keratoconus, and other corneal epithelial injuries. The currently available eye drop solutions need frequent doses affecting the routine life style of patients. In this work, the silicone contact lens was designed to entrap HA and Pluronic®F127 to improve the wettability of the contact lens to treat various ocular diseases. The soaking method (HA-SM) was compared with the direct entrapment (DL-HA-PI) technique. The HA-Pluronic®F127-laden contact lenses (DL-HA-PI) showed acceptable optical transmittance with improved swelling (water content) properties. The in vitro release data showed high burst release with HA-SM contact lenses (12-36 h), while DL-HA-PI contact lenses showed prolong release up to 96 h. The in vivo release in the rabbit tear fluid showed high HA concentration (tear fluid) with DL-HA-PI contact lenses in comparison to the HA-SM contact lenses. The DL-HA-PI-3 batch with Pluronic®F127 showed more promising results in schirmer strip study in comparison to DL-HA-3 batch (without Pluronic®F127). The presence of Pluronic®F127 with HA showed high potential to improve hydration property of the contact lens. The corneal healing model showed reduction in the ocular inflammatory symptoms with DL-HA-PI-3 batch, thus demonstrating the potential of HA and Pluronic®F127 to be used in various ocular diseases.

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-1ß, 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.].

Pressure-Induced Interlamellar Stromal Keratitis After Small-Incision Lenticule Extraction Procedure: A Case Report.

PURPOSE: To report a case of pressure-induced interlamellar stromal keratitis (PISK) after small-incision lenticule extraction (SMILE) for the correction of myopic astigmatism in the United States. METHODS: We report the case of a 27-year-old man who underwent uneventful SMILE surgery and presented with pressure-induced stromal keratitis. Anterior and posterior segment examination, uncorrected distance visual acuity, refraction, intraocular pressure, and pachymetry values are reported from this time period. RESULTS: Three weeks postoperatively, examination revealed new-onset central corneal haze and edema in both eyes, more significant in the right eye. The patient was given a presumptive diagnosis of diffuse lamellar keratitis. Intensive corticosteroid treatment was administered, causing a significant decline in uncorrected distance visual acuity OD from 20/25 to 20/250 and OS from 20/20 to 20/60, with a significant myopic shift of -3.0 D and -1.0 D, respectively. In our case, pachymetry measurements revealed 78 µm OD and 43 µm OS of additional corneal thickness. Pressure readings were 25 mm Hg OD and 19 mm Hg OS, respectively. He was diagnosed with PISK, and after 4 days of steroid discontinuation and Brimonidine-Timolol administration, his symptoms had improved with resolution of corneal edema. CONCLUSIONS: Clinicians should be aware that PISK is a potential complication of SMILE. Postoperative intraocular pressure measurements are an important aspect of the management of postcorneal refractive surgery patients because the differentiation of PISK from diffuse lamellar keratitis, as well as the early detection and treatment of PISK, can avoid severe complications.

Association of Postfungal Keratitis Corneal Scar Features With Visual Acuity.

Importance: Corneal opacity is a leading cause of visual impairment worldwide; however, the specific features of corneal scars, which decrease visual acuity, have not been well characterized. Objective: To investigate which features of a postfungal keratitis corneal scar contribute to decreased visual acuity after an episode of infectious keratitis and evaluate whether any corneal features may be used as outcomes for clinical trials. Design, Setting, and Participants: In this ancillary, prospective cross-sectional study, a subset of study participants treated for fungal keratitis (n = 71) as part of the Mycotic Ulcer Treatment Trial I (MUTT I) underwent best spectacle-corrected visual acuity (BSCVA) and best contact lens-corrected visual acuity examination, Scheimpflug imaging, and anterior segment optical coherence tomography at a referral hospital in India approximately 2 years after enrollment. Data were collected from December 3, 2012, to December 19, 2012, and analyses were performed from December 2, 2013, to October 2, 2019. Main Outcomes and Measures: Linear regression models were used to evaluate the importance of various corneal features for BSCVA and to assess whether these features could be used to differentiate the 2 treatment arms of the MUTT I trial. Results: Seventy-one patients (42 men [59.1%]; median age, 48 [range, 39-60] years) were examined at a median (IQR) time of 1.8 (1.4-2.2) years after enrollment. The mean (SD) logMAR BSCVA was 0.17 (0.19) (Snellen equivalent, 20/32). In multivariable linear regression models, BSCVA was most associated with irregular astigmatism (1.0 line of worse BSCVA per 1-line difference between BSCVA and contact lens visual acuity; 95% CI, 0.6-1.4) and corneal scar density (1.5 lines of worse vision per 10-unit increase in the mean central corneal density; 95% CI, 0.8-2.3). The thinnest point of the cornea was the metric that best discriminated between the natamycin- and voriconazole-treated ulcers in MUTT I, with 29.3 µm (95% CI, 7.1-51.6 µm) less thinning in natamycin-treated eyes. Conclusions and Relevance: Both irregular astigmatism and corneal scar density may be important risk factors for BSCVA in a population with relatively mild, healed fungal corneal ulcers. The thinnest point of the corneal scar may be a cornea-specific outcome that could be used to evaluate treatments for corneal ulcers.

Understanding the Role of Pro-resolving Lipid Mediators in Infectious Keratitis.

Keratitis is a sight-threatening inflammatory condition of the cornea that can be caused by both infectious and non-infectious agents. Physical or chemical trauma are typically related to non-infectious keratitis, which may then become secondarily infected or remain non-infected. Etiology of infectious keratitis is most often associated with bacteria; but viruses, fungi, and parasites are common causative pathogens as well. As a global concern, common risk factors include: systemic immunosuppression (secondary to malnutrition, alcoholism, diabetes, steroid use), previous corneal surgery (refractive corneal surgery, penetrating keratoplasty), extended wear contact lens use, pre-existing ocular surface diseases (dry eye, epithelial defect) and ocular trauma (agriculture- or farm-related) [1-8]. Annual rates of incidence include nearly one million clinical visits due to keratitis in the United States, while it has been reported that roughly two million people develop corneal ulcers in India. Clinically, patients may show signs of eye pain (ranging from mild to severe), blurred vision, photophobia, chemosis and redness. Pathogenesis is generally characterized by rapid progression, focal white infiltrates with underlying stromal inflammation, corneal thinning, stromal edema, mucopurulent discharge and hypopyon, which can lead to corneal scarring, endophthalmitis, and perforation. In fact, corneal opacity is not only a complication of keratitis, but among the leading causes of legal blindness worldwide. Despite that empirical treatment effectively controls most of the pathogens implicated in infectious keratitis, improved clinical outcomes are not guaranteed. Further, if treatment is not initiated in a timely manner, good visual outcome is reduced to approximately 50% of keratitis patients [9]. Moreover, resultant structural alterations, loss of tissue and an unresolved host response remain unaddressed through current clinical management of this condition.

Pain, Dryness, and Itch Sensations in Eye Surface Disorders Are Defined By a Balance Between Inflammation and Sensory Nerve Injury.

Patients with corneal and conjunctival disorders report an array of ocular surface symptoms including stinging, foreign body sensation, and itching. The intensity and perceptual quality of these sensations and their duration, from brief intervals to long-term symptoms, also vary. We hypothesize that symptomatic differences across disorders reflect differences in the balance between ocular inflammation and nerve injury, with different conditions resulting from predominant effects of one of these, or a combined effect. This article provides an overview of corneal and conjunctival nerve cells, such as nociceptors and thermoreceptors, with descriptions of their morphological and molecular characteristics and their nerve-firing patterns and evoked sensations, as determined by earlier studies in animals and humans. Detailed descriptions of the changes in neuronal responses (such as abnormal responsiveness and spontaneous firing) due to local inflammation and nerve injury are provided, and assorted ocular surface disorders are discussed. Eye conditions in which inflammation is predominant include allergic conjunctivitis and photokeratitis, whereas nerve injury is the primary factor underlying complaints of dry eye after photorefractive keratectomy and in elderly patients. Both factors contribute substantially to dry eye disease and varicella-zoster infections. This model of the combined effects of inflammation and nerve injury serves to explain the different sensations reported in various eye surface disorders, including short-term versus chronic pain and dysesthesias, and may help to improve diagnoses and treatment methods.

Management of microbial keratitis in general practice.

BACKGROUND: Microbial keratitis is a medical emergency. Although an uncommon presenting condition to general practitioners, it is potentially vision-threatening. Prompt recognition, management and urgent referral for ophthalmic review are required to minimise vision loss. OBJECTIVE: This article discusses the clinical presentation, examination and management of microbial keratitis in general practice. DISCUSSION: A detailed history and examination are vital for the prompt recognition of microbial keratitis. Risk factors include contact lens wear, underlying ocular surface diseases or trauma and immunosuppressive states. The anterior segment needs to be examined for specific signs of infection. Inadequate management of microbial keratitis can lead to permanent loss of vision.

Corneal autophagy and ocular surface inflammation: A new perspective in dry eye.

Dry eye disease (DED), a multifactorial ocular surface disorder affecting millions of individuals worldwide, is characterized by inflammation and damage to the ocular surface. It is unclear whether corneal autophagy participates in ocular surface inflammation observed in DED. To test this involvement, dry eye (DE) was induced in female C57BL/6 mice housed in a controlled environment by subcutaneous injection of scopolamine. Expression of the autophagy-related proteins LC3B and ATG5 and activation of autophagy were detected in the corneas of these mice. Treatment with LYN-1604, an activator of autophagy, alleviated the clinical indications in DE mice, including tear production and corneal fluorescence staining. LYN-1604 also reduced the corneal levels of inflammatory response products, including tumor necrosis factor alpha (TNF-α) and matrix metalloproteinases-3 and -9. By contrast, treatment of DE mice with the autophagy inhibitor 3-MA, exacerbated the clinical indications of DE and increased the levels of inflammatory response products. This is the first study to show that autophagy could regulate the level of ocular surface inflammation, suggesting that agents that regulate autophagy could relieve ocular surface inflammation and treat DED.

Corneal lymphangiogenesis ameliorates corneal inflammation and edema in late stage of bacterial keratitis.

Lymphatic vessels play a crucial role in systemic immune response and regulation of tissue fluid homeostasis. Corneal lymphangiogenesis in bacterial keratitis has not been studied. In this study, we investigated the mechanism and the role of corneal lymphangiogenesis in a murine bacterial keratitis model using Pseudomonas aeruginosa. We first demonstrated that corneal lymphangiogenesis was enhanced mainly in the late stage of bacterial keratitis, contrary to corneal angiogenesis that started earlier. Corresponding to the delayed lymphangiogenesis, expression of the pro-lymphangiogenic factors VEGF-C and VEGFR-3 increased in the late stage of bacterial keratitis. We further found that F4/80 and CD11b positive macrophages played an essential role in corneal lymphangiogenesis. Notably, macrophages were specifically involved in corneal lymphangiogenesis in the late stage of bacterial keratitis. Finally, we demonstrated the beneficial role of corneal lymphangiogenesis in ameliorating the clinical course of bacterial keratitis. Our study showed that bacterial activity was not directly involved in the late stage of keratitis, while corneal lymphangiogenesis reduced corneal edema and clinical manifestation in the late stage of bacterial keratitis. These findings suggest that the process of lymphangiogenesis in bacterial keratitis ameliorates corneal inflammation and edema in the late stage of bacterial keratitis.

Microbial Keratitis in Thyroid Eye Disease: Clinical Features, Microbiological Profile, and Treatment Outcome.

PURPOSE: To report the incidence, clinical features, microbiologic profile, and risk indicators in the development of microbial keratitis in Thyroid Eye Disease (TED). METHODS: All patients who were diagnosed to have TED and developed microbial keratitis between the years 2009 to 2017 at the Ophthalmic Plastic Surgery service, LV Prasad Eye Institute were included in this retrospective interventional study. The clinical features, microbiological profile, and treatment outcome of the infection were studied. Possible risk factors leading to the development of microbial keratitis were studied. RESULTS: A total of 1,000 patients of TED were evaluated in the 10-year period. Of the 1,000, 13 patients (14 eyes, 1.4%) were diagnosed with microbial keratitis. The average age at presentation was 44 years (range 1969 years). Of the 13 patients, 10 (77%) were men, 12 (92%) were hyperthyroid, and 12 (92%) were active (average clinical activity score 3) at presentation. Average exophthalmometry value in the involved eye was 24.75mm, and severe eyelid retraction (>2mm scleral show) was noted in 13 of 14 eyes. None of the patients had optic nerve compression. Moderate motility restriction (2 in all gazes) was noted in 6 eyes, and severe motility restriction (4 in all gazes) in 8 eyes. At presentation, 11 (85%) had visual acuity of counting fingers at 1 meter or less, The mean follow up from the time of presentation was 18.3 months (range 566 months). Majority of the eyes (8/14) presented with severe infection (panophthalmitis with microbial keratits = 1, total corneal infiltrate with/without melt = 4, severe thinning/perforation = 4). Microbiological work up of 14 eyes revealed presence of gram-negative bacteria in 5 eyes which included Escherichia coli, Pseudomonas sp., and Acinetobacter sp., and gram-positive bacteria in 4 eyes including Streptococcus pneumoniae, Corynebacterium sp., and Staphylococcus sp. Three eyes revealed a mixed infection of E. coli with Alternaria sp, and E. coli with Corynebacterioum amycolatum while 1 had Corynebacterium pseudodiptheriticum, and S. pneumoniae. Two eyes of the bilateral case showed no growth. Antibiotic susceptibility revealed 6 of the 7 gram-negative isolates were multidrug resistant, whereas the gram-positive isolates were susceptible to most drugs tested. Surgical procedures required were tarsorrhaphy in 7 eyes, tissue adhesive with bandage contact lens in 4, evisceration in 4, levator recession in 2, 3-wall orbital decompression in 2, and penetrating keratoplasty in 1 eye. The visual acuity at presentation was counting fingers or worse in 10/14 eyes. Posttreatment, 10 eyes achieved resolution of infiltrate (with visual improvement in 2), and 4 required evisceration. CONCLUSIONS: In the authors large series of TED, microbial keratitis was noted in 1.3% of patients presenting to a tertiary eye center. Majority presented with advanced diseases and ended with a poor outcome. Gram-negative isolates showed multidrug resistance. An association with early phase of active TED (CAS 3 or more), severe eyelid retraction, and moderate-severe motility restriction is suggested.Microbial Keratitis occurs in 1.3% cases of Thyroid Eye Disease. It is more common in men, and in active disease. The microbiological spectrum and possible clinical risk factors are presented.

More than keratitis, ichthyosis, and deafness: Multisystem effects of lethal GJB2 mutations.

BACKGROUND: Infant death in keratitis-ichthyosis-deafness (KID) syndrome is recognized; its association with specific genotypes and pathophysiology is inadequately understood. OBJECTIVE: We sought to discover characteristics that account for poor outcomes in lethal KID syndrome. METHODS: We collected 4 new cases and 9 previously reported, genotyped cases of lethal KID syndrome. We performed new molecular modeling of the lethal mutants GJB2 p.A88V and GJB2 p.G45E. RESULTS: Infant death occurred in all patients with GJB2 p.G45E and p.A88V; it is unusual with other GJB2 mutations. Early death with those 2 "lethal" mutations is likely multifactorial: during life all had ≥1 serious infection; most had poor weight gain and severe respiratory difficulties; many had additional anatomic abnormalities. Structural modeling of GJB2 p.G45E identified no impact on the salt bridge previously predicted to account for abnormal central carbon dioxide sensing of GJB2 p.A88V. LIMITATIONS: This clinical review was retrospective. CONCLUSION: GJB2 p.G45E and p.A88V are the only KID syndrome mutations associated with uniform early lethality. Those electrophysiologically severe mutations in GJB2 reveal abnormalities in many organs in lethal KID syndrome. All patients with KID syndrome may have subtle abnormalities beyond the eyes, ears, and skin. Early genotyping of KID syndrome births will inform prognostic discussion.

Successfully Improving Visual Acuity in Keratitis-Ichthyosis-Deafness Syndrome Utilizing Gas-Permeable Lenses: A Case Report.

There is currently no well-defined guideline for treatment and management of patients with keratitis-ichthyosis-deafness (KID) syndrome, and most patients will face disabling vision loss due to corneal neovascularization and cicatrization. We offer this case as an example of how we can improve visual acuity (VA) and quality of life even in advanced cases of corneal neovascularization. We showcase the use of gas-permeable (GP) contact lenses to provide useful, functional VA in a patient with long-standing visual impairment secondary to corneal neovascularization and irregularity due to KID syndrome. The patient's VA improved from 20/200 both eyes (OU) to 20/40 OU with successful fitting of GP lenses, which additionally relieved the patient's otherwise intractable monocular diplopia.

Risk Factors for Sporadic Diffuse Lamellar Keratitis After Microkeratome Laser-Assisted In Situ Keratomileusis: A Retrospective Large Database Analysis.

PURPOSE: To determine the factors associated with sporadic diffuse lamellar keratitis (DLK) after microkeratome laser-assisted in situ keratomileusis (LASIK). METHODS: This large database retrospective study included consecutive cases of LASIK performed between 2007 and 2016 at Care-Vision Laser Centers, Tel-Aviv, Israel. Patients were divided into 2 groups according to whether or not they subsequently developed DLK. RESULTS: A total of 24,026 eyes of 12,013 patients with a mean age of 32.9 ± 10.3 years were included. Post-LASIK DLK developed in 464 eyes (1.9%), and the annual rate decreased from 7.1% (2007) to 1.7% (2016) (P < 0.001). The DLK group had a higher proportion of males (58.5% vs. 52.1%, P = 0.006), greater preoperative central corneal thickness (549.5 ± 32.6 vs. 545.3 ± 30.5 µm, P = 0.005), and a lower proportion of high astigmatism (>3 D) (0.4% vs. 1.6%, P = 0.05). The DLK group had a higher proportion of previous LASIK treatment (2.8% vs. 1.3%, P = 0.006), Moria M2 (rather than the SBK) microkeratome (71.1% vs. 34.0%, P < 0.001), smaller suction ring number (P < 0.001), greater stop size (P < 0.001), and greater flap thickness (119.2 ± 50.4 vs. 110.8 ± 22.2, P = 0.007). In multivariable analysis, a smaller suction ring number [odds ratio (OR) 0.89, P = 0.04], Moria M2 microkeratome (OR 5.26, P < 0.001), larger optical zone (OR = 2.04, P = 0.01), and higher spherical equivalent (OR = 1.08, P = 0.02) were associated with DLK. CONCLUSIONS: In the modern LASIK era, the incidence of DLK continues to decrease. Higher preoperative ametropia, smaller suction ring number, an older type of microkeratome, and larger optical zones are associated with higher DLK rates after LASIK.

Mast Cell Activation Protects Cornea by Promoting Neutrophil Infiltration via Stimulating ICAM-1 and Vascular Dilation in Fungal Keratitis.

The role of mast cells (MCs) in fungal infection is largely unknown. This study was to explore a protective role and mechanism of MCs in fungal keratitis. Experimental fungal keratitis (FK) mouse model was developed. Mice untreated (UT) or receiving corneal wound without fungal infection (Mock) were used as controls. Large number of connective tissue MCs was found in normal mice. MC activation with degranulation was largely observed, and the percentage of degranulated/total cells was high in FK. Dilated limbal vasculature with increased permeability, as well as largely infiltrated neutrophils with stimulated ICAM-1 protein levels were observed in corneas of FK mice, when compared with Mock and UT mice. Interestingly, pretreatment with cromolyn sodium (Block) significantly blocked MC degranulation, dramatically suppressed vascular dilation and permeability, and markedly reduced neutrophil infiltration with lower ICAM-1 levels in FK mice at 6-24 hours. Furthermore, the Block mice manifested prolonged disease course, increased pathological damage, and vigorous fungus growth, with much higher corneal perforation rate than FK mice at 72 h. These findings reveal a novel phenomenon that MCs play a vital role in protecting cornea against fungal infection through degranulation that promotes neutrophil infiltration via stimulating ICAM-1 production and limbal vascular dilation and permeability.

Adenoviral keratitis: a review of the epidemiology, pathophysiology, clinical features, diagnosis, and management.

PURPOSE OF REVIEW: Adenoviral keratitis is a common and bothersome ocular infection that produces a lot of burden on healthcare systems and patients. The goal of this article is to provide a review of the topic, with an emphasis on current attempts at advancing strategies in diagnosis and management. RECENT FINDINGS: Sixty-eight articles and one textbook published on adenoviral keratitis were reviewed. The findings on the epidemiology, pathophysiology, clinical features, diagnosis, and management were summarized. Any contradicting opinions for which the literature was unclear were either omitted or recorded as lacking strong evidence. SUMMARY: Although significant effort has been made to develop new methods for diagnosis and management, adenoviral keratitis is predominantly diagnosed clinically with prevention being the mainstay of management. The use of newer DNA analysis techniques and topical anti-inflammatory agents for treatment of corneal infiltrates show promising results, but a better understanding of the pathogenesis and clinical features can lead to more targeted methods of diagnosis and therapy.