Alterações oculares decorrentes de picada de abelha na córnea / Ocular changes due to corneal bee sting

RESUMO O propósito deste estudo foi reportar as alterações oculares observadas após picada de abelha com ferrão retido na córnea. Destacamos o tratamento e o desfecho de uma lesão de córnea incomum e sua patogênese. Trata-se de relato de caso e revisão da literatura de lesões oculares por picada de abelha. Paciente do sexo feminino, 63 anos, procurou atendimento oftalmológico de urgência devido à picada de abelha na córnea do olho direito há 6 dias. Queixava-se de embaçamento visual, dor e hiperemia ocular. Apresentou acuidade visual de vultos no olho afetado. Ao exame, notaram-se hiperemia moderada de conjuntiva bulbar, edema corneano com dobras de Descemet e presença do ferrão alojado na região temporal, no estroma profundo da córnea. A paciente foi internada para ser abordada no centro cirúrgico sob anestesia geral. Durante a cirurgia, o ferrão teve que ser retirado via câmara anterior, mediante a realização de uma paracentese e uma lavagem da câmara anterior, com dupla via e solução salina balanceada. Ainda não existe na literatura um tratamento padrão na abordagem de pacientes com lesões oculares por picada de abelha, sendo importantes a identificação e o reconhecimento precoce de possíveis complicações que ameacem a visão.

ABSTRACT The purpose of this study was to report the ocular changes observed after a bee sting with a stinger retained in the cornea. We show the treatment and outcome of an unusual corneal injury and its pathogenesis. This is a case report and literature review of ocular injuries caused by bee stings. A 63-year-old female patient sought emergency ophthalmic care because of a bee sting on the cornea of her right eye six days before. She complained of blurred vision, pain, and ocular hyperemia. She had glare sensitivity on visual acuity in the affected eye. Examination revealed moderate hyperemia of the bulbar conjunctiva, corneal edema with Descemet's folds and a stinger lodged in the temporal region, in the deep stroma of the cornea. The patient was admitted to the operating room under general anesthesia. During surgery, the stinger had to be removed via the anterior chamber, by performing a paracentesis and washing the anterior chamber with a double flushing and balanced saline solution. There is still no standard treatment in the literature for patients with eye injuries caused by bee stings, and early identification and recognition of possible sight-threatening complications is important.

Prognostic factors for visual outcome after surgical repair of limbal corneal laceration at a tertiary eye care center in South India.

Purpose: To determine the factors affecting the visual outcome after surgical repair of limbal corneal lacerations at a tertiary eye care center in South India. Methods: A retrospective analysis of patients diagnosed with limbal tears between 2011 and 2021 was conducted. Demographic information such as age, gender, cause of injury, and size of the laceration was recorded. Comprehensive ocular examination was performed, including gentle B scan evaluation whenever not contraindicated for detailed posterior segment evaluation. Only those cases with a minimum follow-up of one year were included. Postoperative best-corrected visual acuity, intraocular pressure (IOP), cornea clarity, and integrity of the wound at last follow-up were noted. Results: Out of the 20 patients, 15 (75%) were males and 5 (25%) were females. The mean age was 42.6 ± 22.4 years. All 20 patients had a penetrating injury, with four (20%) injured by a stick, two (10%) by an iron rod, three (15%) due to road traffic accident (RTA), three (15%) by glass, and eight (40%) with other nonspecific objects [two (10%) with needle, two (10%) with elastic rope, two (10%) with bangle, and two (10%) with metal]. The average time between the injury and the surgery was 48 hours (2 days). Four (20%) patients underwent a second surgery within a week of repair. After limbal tear repair, at final follow-up at 3 years, 7 (35%) had VA worse than 20/800, 3 (15%) had VA between 20/100 and 20/800, and 10 (50%) achieved VA better than 20/80. Conclusion: Preoperative visual acuity (VA), mode of injury, and size of wound affect the final visual outcome after surgical repair of limbal corneal laceration. Preoperative VA and mode of injury were statistically significant even in the multivariate analysis.

Traumatic dislocation of the iris into the vitreous cavity with intact lens: a case report.

BACKGROUND: Traumatic aniridia occurs when the iris is extruded from the eye and is often accompanied by lens injuries. However, traumatic aniridia due to dislocation of the iris into the vitreous cavity without lens damage has never been reported. CASE PRESENTATION: A 30-year-old man presented with visual loss and pain for 6 h after a thin wire injured his right eyeball. Ophthalmologic examinations manifested a 2 mm full-thickness corneal laceration and total hyphema. An intact clear lens, healthy attached retina, and almost complete iris tissue in the vitreous cavity were found after resolution of hyphema the next day. Further examination revealed that the defect in the zonule below the corneal wound was the path for the iris to enter the vitreous cavity. The patient opted for nonsurgical treatment until pigment granules and opacity were observed in the vitreous cavity after 50 days. Vitrectomy was performed to remove the dislocated iris. CONCLUSIONS: The presentation of this unique case indicates that the torn iris was displaced to the vitreous cavity with an intact lens and missing local zonula instead of out the corneal laceration after a penetrating injury. The type of injury, mechanism, and force on the spot may contribute to the occurrence of this rare condition. Instead of artificial irises, tinted glasses were more appropriate treatment option for this patient. Peripheral retinal examination was essential in the management of this case. In such cases, the iris in the vitreous cavity should be resected to prevent complications.

Corneal epithelial ingrowth after perforating corneal injury: a case report.

BACKGROUND: Epithelial ingrowth is a rare complication after ocular perforation and can become manifest many years after the primary trauma. CASE PRESENTATION: A 49-year-old patient presented with a positive Seidel test of unclear origin at her left eye, as well as a sharply defined anterior-stromal corneal scar at both eyes. Prior operations included a bilateral laser-assisted blepharoplasty 3 months earlier. The patient indicated to have been on holiday to France 5 months earlier, during an ongoing oak processionary moth caterpillars infestation. The examination using confocal microscopy confirmed a corneal perforation at the left eye and revealed corneal epithelial ingrowth capped with scarred stroma in both eyes. We performed a penetrating keratoplasty at the left eye. The scarred and perforated host cornea was divided into 4 pieces for further investigation: microbiology (negative), virology (negative), histology and transmission electron microscopy (TEM). Histology revealed differently structured epithelium, centrally inverted into the stroma through defects in Bowman's layer. TEM revealed full thickness corneal perforation with an epithelial plug extending to the lower third of the cornea, but without evidence of epithelial cell migration into the anterior chamber. Our differential diagnosis of the unclear positive Seidel test with epithelial ingrowth was as follows: (1) corneal perforation by hairs of the oak processionary moth caterpillar, although no hairs could be found histologically; (2) corneal perforation during laser-assisted blepharoplasty, which may be supported by the presence of pigmented cells on the posterior surface of Descemet´s membrane, pointing to a possible iris injury. CONCLUSION: Consequently, we highlighted that contact lenses can be useful, safe and inexpensive protective devices in upper eyelid procedures to protect the cornea against mechanical iatrogenic trauma.

Evaluating Depth and Width of Corneal Wounds Using Anterior Segment Optical Coherence Tomography After Foreign Body Removal.

PURPOSE: To determine corneal foreign body (FB) location together with corneal wound depth and width by using anterior segment optical coherence tomography (AS-OCT) after uncomplicated FB removal. METHOD: This prospective study was conducted with patients injured by a superficial metallic corneal FB. Under slit-lamp examination, after determining its location, the FB was removed with a 27-G needle. The depth and width of the corneal wound and the thinnest stromal thickness at the wound site were measured initially using AS-OCT. Measurements were repeated to assess the wound healing process at one week and at two months following FB removal. RESULTS: Totally, 63 eyes of 63 patients were included in this study. The average age was 35.8 ± 11.0 years, and 96.8% of the patients were men. In terms of location of the FBs, 26 (41.3%) were in the central region, 21 (33.3%) were in the paracentral region, and 16 (25.4%) were in peripheral regions. The mean depth and width of the corneal wounds were 117.0 ± 42.5 µm and 332.9 ± 99.4 µm, respectively. The mean percentage of corneal wound depth was 18.9 ± 6.1%. In 20 patients who presented for follow-up, it was observed that the width of the wound increased and the thinnest stromal thickness at the wound site decreased over the two months. CONCLUSION: The AS-OCT findings of the present study showed that the corneal FBs generally affected the anterior cornea with less than approximately 0.2 mm depth and 0.5 mm width. In addition, FBs were commonly located in the central and paracentral cornea.

Phenotypic and Transcriptomics Analyses Reveal Underlying Mechanisms in a Mouse Model of Corneal Bee Sting.

Corneal bee sting (CBS) is one of the most common ocular traumas and can lead to blindness. The ophthalmic manifestations are caused by direct mechanical effects of bee stings, toxic effects, and host immune responses to bee venom (BV); however, the underlying pathogenesis remains unclear. Clinically, topical steroids and antibiotics are routinely used to treat CBS patients but the specific drug targets are unknown; therefore, it is imperative to study the pathological characteristics, injury mechanisms, and therapeutic targets involved in CBS. In the present study, a CBS injury model was successfully established by injecting BV into the corneal stroma of healthy C57BL/6 mice. F-actin staining revealed corneal endothelial cell damage, decreased density, skeletal disorder, and thickened corneal stromal. The terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) assay showed apoptosis of both epithelial and endothelial cells. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that cytokine-cytokine interactions were the most relevant pathway for pathogenesis. Protein-protein interaction (PPI) network analysis showed that IL-1, TNF, and IL-6 were the most relevant nodes. RNA-seq after the application of Tobradex® (0.3% tobramycin and 0.1% dexamethasone) eye ointment showed that Tobradex® not only downregulated relevant inflammatory factors but also reduced corneal pain as well as promoted nerve regeneration by repairing axons. Here, a stable and reliable model of CBS injury was successfully established for the first time, and the pathogenesis of CBS and the therapeutic targets of Tobradex® are discussed. These hub genes are expected to be biomarkers and therapeutic targets for the diagnosis and treatment of CBS.

dsRNA Induced IFNß-MMP13 Axis Drives Corneal Wound Healing.

Purpose: Cornea, the outermost transparent layer of the eye, is the first line of defense against external threats. Following injury, the wound healing response is crucial to corneal repair and regeneration, yet its underlying mechanism is poorly understood. Our study was designed to investigate the role of dsRNA and its regulatory network in corneal wound healing. Methods: A corneal wound healing model was established via the surgical removal of half of the corneal surface and adjoining limbus. RNase III was then used to clarify the role of dsRNA in corneal wound closure and RNA-seq was performed to investigate the mechanism of dsRNA in the healing process. Related gene expression was assessed using immunofluorescence staining, qPCR, and Western blot. Flow cytometry and scratch assay were used to analyze the proliferation and migration of limbal stem/progenitor cells (LSCs) in vitro and functional analysis of the target genes was completed using the corneal wound healing model. Results: Corneal wound healing was delayed and impaired when the dsRNAs were removed or damaged following RNase III digestion. The dsRNAs released following corneal damage activate type I interferon (IFN-I) signaling, primarily IFNß, via the corneal epithelium and neutralizing IFNß or blocking IFN-I signaling delays corneal wound closure. Moreover, our data identified MMP13 as a downstream effector of IFNß where its expression promotes LSC proliferation and enhances corneal epithelial reconstruction in vivo. Conclusions: The dsRNA induced IFNß-MMP13 axis plays a key role in corneal wound healing.

Nonaccidental trauma: bilateral corneal abrasions as only initial presentation.

We report a case of nonaccidental trauma in a child who presented emergently with bilateral corneal abrasions of unclear etiology. It was later discovered that these lesions were actually caused by the newborn's father, who had forcefully pressed his thumbs against the child's orbits. Although uncommon, such types of anterior segment pathology should raise suspicion of nonaccidental trauma.

Corneal Opacity: Cell Biological Determinants of the Transition From Transparency to Transient Haze to Scarring Fibrosis, and Resolution, After Injury.

Purpose: To highlight the cellular, matrix, and hydration changes associated with opacity that occurs in the corneal stroma after injury. Methods: Review of the literature. Results: The regulated transition of keratocytes to corneal fibroblasts and myofibroblasts, and of bone marrow-derived fibrocytes to myofibroblasts, is in large part modulated by transforming growth factor beta (TGFß) entry into the stroma after injury to the epithelial basement membrane (EBM) and/or Descemet's membrane. The composition, stoichiometry, and organization of the stromal extracellular matrix components and water is altered by corneal fibroblast and myofibroblast production of large amounts of collagen type I and other extracellular matrix components-resulting in varying levels of stromal opacity, depending on the intensity of the healing response. Regeneration of EBM and/or Descemet's membrane, and stromal cell production of non-EBM collagen type IV, reestablishes control of TGFß entry and activity, and triggers TGFß-dependent myofibroblast apoptosis. Eventually, corneal fibroblasts also disappear, and repopulating keratocytes reorganize the disordered extracellular matrix to reestablish transparency. Conclusions: Injuries to the cornea produce varying amounts of corneal opacity depending on the magnitude of cellular and molecular responses to injury. The EBM and Descemet's membrane are key regulators of stromal cellularity through their modulation of TGFß. After injury to the cornea, depending on the severity of the insult, and possibly genetic factors, trace opacity to severe scarring fibrosis develops. Stromal cellularity, and the functions of different cell types, are the major determinants of the level of the stromal opacity.

Treatment of Non-Infectious Corneal Injury: Review of Diagnostic Agents, Therapeutic Medications, and Future Targets.

Corneal injuries can occur secondary to traumatic, chemical, inflammatory, metabolic, autoimmune, and iatrogenic causes. Ocular infection may frequently occur concurrent to corneal injury; however, antimicrobial agents are excluded from this present review. While practitioners may primarily rely on clinical examination techniques to assess these injuries, several pharmacological agents, such as fluorescein, lissamine green, and rose bengal, can be used to formulate a diagnosis and develop effective treatment strategies. Practitioners may choose from several analgesic medications to help with patient comfort without risking further injury or delaying ocular healing. Atropine, cyclopentolate, scopolamine, and homatropine are among the most frequently used medications for this purpose. Additional topical analgesic agents may be used judiciously to augment patient comfort to facilitate diagnosis. Steroidal anti-inflammatory agents are frequently used as part of the therapeutic regimen. A variety of commonly used agents, including prednisolone acetate, loteprednol, difluprednate, dexamethasone, fluorometholone, and methylprednisolone are discussed. While these medications are effective for controlling ocular inflammation, side effects, such as elevated intraocular pressure and cataract formation, must be monitored by clinicians. Non-steroidal medications, such as ketorolac, bromfenac, nepafenac, and diclofenac, are additionally used for their efficacy in controlling ocular inflammation without incurring side effects seen with steroids. However, these agents have their own respective side effects, warranting close monitoring by clinicians. Additionally, ophthalmologists routinely employ several agents in an off-label manner for supplementary control of inflammation and treatment of corneal injuries. Patients with corneal injuries not infrequently have significant ocular surface disease, either as a concurrent pathology or as an exacerbation of previously existing disease. Several agents used in the management of ocular surface disease have also been found to be useful as part of the therapeutic armamentarium for treatment of corneal injuries. For example, several antibiotics, such as doxycycline and macrolides, have been used for their anti-inflammatory effects on specific cytokines that are upregulated during acute injuries. There has been a recent wave of interest in amniotic membrane therapies (AMTs), including topical, cryopreserved and dehydrated variants. AMT is particularly effective in ocular injuries with violation of corneal surface integrity due to its ability to promote re-epithelialization of the corneal epithelium. Blood-based therapies, including autologous serum tears, plasma-enriched growth factor eyedrops and autologous blood drops, have additionally been explored in small case series for effectiveness in challenging and recalcitrant cases. Protection of the ocular surface is also a vital component in the treatment of corneal injuries. Temporary protective methods, such as bandage contact lenses and mechanical closure of the eyelids (tarsorrhaphy) can be particularly helpful in selective cases. Glue therapies, including biologic and non-biologic variants, can also be used in cases of severe injury and risk of corneal perforation. Finally, there are a variety of recently introduced and in-development agents that may be used as adjuvant therapies in challenging patient populations. Neurotrophic corneal disease may occur as a result of severe or chronic injury. In such cases, recombinant human nerve growth factor (cenegermin), topical insulin, and several other novel agents may be an alternate and effective option for clinicians to consider.

[Combined transepithelial PTK and topography-guided PRK for treatment of trauma-related corneal scarring]. / Kombinierte transepitheliale PTK und topografiegesteuerte PRK zur Behandlung von traumatisch bedingten Hornhautnarben.

BACKGROUND: Corneal scars can severely impair visual performance and treatment can be challenging. The study aimed to evaluate a promising minimally invasive option in the treatment of corneal scars using transepithelial topography-guided ablation. METHODS: This retrospective interventional study involved four eyes of four patients who developed corneal scarring and irregular surfaces due to trauma and were treated with topography-guided photorefractive keratectomy (TG-PRK) between 2017 and 2020. The ablation profile was calculated in all four cases using CRS-Master (Zeiss, Jena, Germany). The main outcome measures were uncorrected and best-corrected distance visual acuity, manifest refraction and corneal regularity by topographic images. The mean age was 34.75 ± 15.39 years and the follow-up time was 6 months for all patients. RESULTS: In three cases full subjective refraction was corrected in one session and one patient had a refractive error of +0.5 D. Only corneal surface smoothing without additional refractive correction was performed in this case. All four patients showed improvement in uncorrected (2-3 Snellen lines) and corrected (3 Snellen lines) distance visual acuity. No complications occurred during or after the treatment and there was no reduction of visual acuity in any case. CONCLUSION: The use of TG-PRK in patients with corneal scarring improves visual acuity in selected cases. In myopic patients most of the refractive error can also be corrected in a single session.

Collateral damage: Corneal injury due to mask use during the COVID-19 pandemic - A case series.

Though masks are the best shield against COVID-19, they can be a source of discomfort and ocular side effects. We discuss three cases of corneal injury due to mask use. Three patients, who were healthcare workers, presented with discomfort, photophobia, and pain in the eyes. While adjusting the mask, they had an ocular injury. There were multiple superficial linear abrasions in the eyes. They recovered with treatment. Though masks are imperative during the COVID-19 pandemic, it is important to be aware of a possible mask injury.

Ocular Trauma Caused by Confetti Cannons.

BACKGROUND: Eye trauma is an unfortunate and often preventable cause of vision loss. Confetti cannons are common causes of injury. Awareness of ocular hazards of confetti cannons remains low because of limited reports describing ophthalmic injuries following their use. OBJECTIVES: To describe outcomes of ocular trauma caused by confetti cannons and to increase recognition of their ocular risks. METHODS: A retrospective analysis was conducted of eye injuries caused by confetti cannons presenting to a single medical center between 2016 and 2020. Data collected included age, gender, eye injured, ocular damage, visual outcome, and details of surgeries performed. RESULTS: Overall, six consecutive patients (2 males, mean age 19.5 ± 9.74 years) were identified and studied. In all patients only one eye was injured (3 right eyes) during a private celebration, most commonly (n=5) to a bystander while in the vicinity of a cannon operated by someone else. Most common eye injuries included corneal erosion (n=4), traumatic hyphema (n=4), and retinal edema (n=3). Mean initial logMAR visual acuity in the injured eye was 0.73 ± 0.18, improving to 0.25 ± 0.16 at the final visit (P = 0.125). Two patients underwent eye surgery due to their trauma: one to repair globe penetration and another to undergo intravitreal injection of tissue plasminogen activator and C3F8 for submacular hemorrhage, followed 8 months later by intravitreal bevacizumab injection for choroidal neovascularization. CONCLUSIONS: Confetti cannons pose hazards that can cause severe ocular trauma resulting in permanent vision loss. Increasing awareness of device hazards is necessary to prevent eye injuries.