Establishing an Animal Model of Cytomegalovirus Keratouveitis in Rats: Broad Infection of Anterior Segment Tissue by Cytomegalovirus.

Purpose: Considering the difficulty of obtaining adequate biological tissue in clinical practice, we established an animal model of cytomegalovirus (CMV) keratouveitis in rats and investigated the viral infection sites and corresponding imaging and histopathological features. Methods: Subconjunctival injection and topical use of dexamethasone were used to induce ocular immunosuppression in rats followed by intracameral inoculation of murine cytomegalovirus (MCMV). The clinical manifestations, intraocular pressure (IOP) and imaging changes were observed. Infected eyes were further examined by immunofluorescence, light microscopy, and electron microscopy. MCMV RNA was detected by reverse transcription-polymerase chain reaction. Results: Typical keratouveitis occurred in the experimental rats and was characterized by corneal edema, keratic precipitates, and iridocyclitis with increased IOP. Corneal endothelial lesions displayed as "black holes," enlarged intercellular gaps, and high-intensity cellular infiltration by confocal microscopy, consistent with the pathological changes of "ballooning degeneration," endothelial cell detachment, and inflammatory cell infiltration. Mitochondrial edema was the most prominent organelle lesion in endothelial cells. Trabeculitis, mechanical obstruction of Schlemm's canal, and anterior chamber angle stenosis accounted for elevated IOP. Inflammation of the iris and ciliary body tended to transform into a chronic form. Immunofluorescence revealed that corneal endothelial cells, iris cells, trabecular meshwork cells, and monocytes could be infected by MCMV. MCMV RNA was found in the anterior segments after infection. Conclusions: CMV can widely infect anterior segment tissue, including the corneal endothelium, iris, and trabecular meshwork, in vivo, inducing the corresponding clinical manifestations. Corneal endotheliitis and hypertensive anterior uveitis could be the specific stage of anterior segment infection of CMV.

Severe Intraocular Inflammation following Hydrophilic Acrylic Phakic Intraocular Lens Implantation in A Case with Concealed History of COVID-19: A Case Report and Literature Review.

Purpose: To firstly present management of toxic anterior segment syndrome (TASS) and possible postoperative endophthalmitis (POE) after implantation of a new hydrophilic-acrylic posterior chamber (PC) phakic intraocular lens (pIOL) in a case with undeclared history of COVID-19.Methods: A 21-year-old male without known disease represented severe anterior chamber inflammation (hypopyon), poor vision and corneal edema without vitreous involvement (TASS) at 24-hours after PC-pIOL implantation for unilateral high myopia (amblyopic).Results: Preoperative best-corrected visual acuity (BCVA) was 0.2 OS (-13 diopters). At 56-hours, vitreous was involved with visual loss indicating POE. The patient confessed that he had COVID-19 1-month ago. COVID-19 immunoglobulin M/G tests were positive, while other markers were negative. Intracameral/intravitreal antibiotics were applied. BCVA was 0.15 without hypopyon at 24-hours. Cultures were negative. Final BCVA was 0.6 with normal examination.Conclusion: TASS/POE etiology could not be demonstrated in this case, whereas COVID-19-related proinflammatory systemic background could have effect on triggering/aggravating this scenario.].

In Vivo Analysis and Comparison of Anterior Segment Structures of Both Eyes in Unilateral Herpetic Anterior Uveitis.

Purpose: To compare the Schlemm's canal area (SCA) and to define iris features in patients with unilateral herpetic anterior uveitis (HAU) by using anterior segment spectral-domain optical coherence tomography (AS SD-OCT).Methods: Unilateral HAU cases that had been in complete remission for ≥ 3 months were included. Two investigators analyzed the iris features of HAU. SCA in both healthy (N), and affected eyes (HAU) were compared.Results: The mean age of the participants (n = 22) was 36.3 ± 15 (17-70) years. The mean nasal and temporal (n-t) SCA was measured as 10,844 ± 4806 µm2 and 8,772 ± 3138 µm2 in HAU in comparison with 10,200 ± 4,824 µm2 and 10,045 ± 3,889 µm2 in N, respectively (p = .47 and p = .12, respectively). The most common iris features were the sectoral iridoplegia (100%) on biomicroscopy and the disorganization of the iris layers (DIL) (77%) on AS SD-OCT images.Conclusion: SCA found similar on both sides. DIL is the most common iris feature of affected eyes.

[Quantitative evaluation of infectious keratitis by anterior segment optical coherence tomography]. / Évaluation quantitative des kératites infectieuses par tomographie en cohérence optique du segment antérieur.

The clinical evaluation of infectious keratitis takes place largely through biomicroscopic examination, which presents limitations in the evaluation of the depth of the infiltrate and the exact thickness of the cornea, whether edematous or thinned. In this study, we aim to quantify the human corneal inflammatory response in treated infectious keratitis by anterior segment optical coherence tomography (AS-OCT). Patients with infectious keratitis were recruited prospectively in the ophthalmology department of the military hospital of Rabat between November 2017 and May 2019. Over the study period, 32 patients were included. A standardized scanning protocol was used. The thickness of the infiltrate, when present, and corneal thickness in any area of thinning and any surrounding edematous areas were measured. The various thicknesses gradually decreased over the course of follow-up, providing objective evidence of therapeutic efficacy in the early stages. Improvement in corneal edema and thinning was faster in the early stage. AS-OCT scanning can be used along with slit lamp examination to quantify and objectively follow infectious keratitis.

Diagnosis of Cytomegalovirus Anterior Uveitis in Two European Referral Centers.

PURPOSE: To evaluate diagnostic methods and clinical signs of CMV anterior uveitis (AU), a rarely described entity in Europe. METHODS: We included patients with clinical characteristics of CMV AU and positive PCR and/or Goldmann-Witmer coefficient (GWc) for CMV. RESULTS: We report 21 patients with unilateral uveitis (100%) and signs of Posner-Schlossman syndrome (PSS) (n = 20, 95.2%), Fuchs uveitis syndrome (FUS) (n = 1, 4.7%), and endotheliitis (n = 4, 19,04%). PCR was positive in 15/21 (71.4%) and GWc in 8/9 patients (88.9%) in aqueous for CMV. GWc was the only positive test in 6/9 patients (66,6%). When PCR alone was performed (without GWc) in the first tap, repeated aqueous taps were needed, twice in five cases and thrice in one case. CONCLUSION: Combining PCR and GWc were very helpful to confirm the clinical diagnosis of CMV AU. In case of very high clinical suspicion and negative results, repeated tap seems to be recommended.

Herpes Simplex Virus Disease of the Anterior Segment in Children.

PURPOSE: To analyze the clinical presentation, characteristics, treatment, recurrences, and final outcomes and complications of herpes simplex virus (HSV) disease of the anterior segment in patients aged 17 years or younger. METHODS: This is an observational and retrospective study with review of the medical records of all the children diagnosed with herpes simplex infection of the anterior segment at an ophthalmologic referral center, from 2002 to 2012. The diagnosis was made on the basis of the history and examination of patients and in specific cases by viral culture and the polymerase chain reaction. Main outcome measurements included final visual acuity, bilateral disease, and recurrence. Recurrent disease was analyzed with Kaplan-Meier curves. RESULTS: A total of 103 patients were included with a median age at presentation of 9 years. Of them, 6 had bilateral and simultaneous disease. The median follow-up time was 18 months (range, 18 days-12 years). The most common clinical manifestations were epithelial dendritic keratitis in 42 eyes (38.5%) and interstitial keratitis in 39 eyes (35.7%), with 15 patients presenting multiple forms of HSV disease. The median final visual acuity in the group of patients was 20/40. Recurrent disease was evident in 42 (38.5%) of the eyes, with a median recurrence time of 15 months (95% confidence interval, 8.1-26.2 months). CONCLUSIONS: In this study, epithelial dendritic and interstitial keratitis were the most frequent forms of disease in the pediatric population with HSV of the anterior segment. A high rate of recurrent disease was present.

Pediatric herpes simplex of the anterior segment: characteristics, treatment, and outcomes.

PURPOSE: To describe the clinical characteristics, treatment, and outcomes of herpes simplex virus (HSV) infections of the cornea and adnexae to raise awareness and to improve management of this important eye disease in children. DESIGN: Retrospective case series. PARTICIPANTS: Fifty-three patients (57 eyes) 16 years of age or younger with HSV keratitis (HSK), HSV blepharoconjunctivitis (HBC), or both in an academic cornea practice. METHODS: The following data were collected: age at disease onset, putative trigger factors, coexisting systemic diseases, duration of symptoms and diagnoses given before presentation, visual acuity, slit-lamp examination findings, corneal sensation, dose and duration of medications used, drug side effects, and disease recurrence. MAIN OUTCOME MEASURES: Presence of residual corneal scarring, visual acuity at the last visit, changes in corneal sensation, recurrence rate, and manifestations of HSK were assessed in patients receiving long-term prophylactic systemic acyclovir. RESULTS: The median age at onset was 5 years. Mean follow-up was 3.6 years. Eighteen eyes had HBC only; 4 patients in this group had bilateral disease. Of 39 eyes with keratitis, 74% had stromal disease. Thirty percent of HSK cases were misdiagnosed before presentation. Seventy-nine percent of patients with keratitis had corneal scarring and 26% had vision of 20/40 or worse at the last visit. Eighty percent of patients had recurrent disease. Six of 16 patients (37%) receiving long-term oral acyclovir had recurrent HSV, at least one case of which followed a growth spurt that caused the baseline dosage of acyclovir to become subtherapeutic. CONCLUSIONS: In a large series, pediatric HSK had a high rate of misdiagnosis, stromal involvement, recurrence, and vision loss. Oral acyclovir is effective, but the dosage must be adjusted as the child grows.

Cytomegalovirus and the eye.

Following primary infection, cytomegalovirus (CMV) establishes latent infection in myeloid progenitor cells and intermittent viral reactivation from activated macrophages or dendritic cells, which is brought under control by strong virus-specific CD4+ T-cell and CD8+ T-cell responses. CMV retinitis characterized by spreading retinal necrosis due to viral cytopathic effect occurs in patients who have impaired T-cell function as a result of transplantation, AIDS, or immuno-suppressive treatment. The diagnosis of CMV retinitis can be confirmed by PCR amplification of viral DNA in aqueous. When administered intravenously, the antiviral drugs Ganciclovir and Foscarnet have modest penetration into the vitreous compared with direct intra-vitreal injection. In randomized trials of HIV-associated CMV retinitis, a Ganciclovir implant was consistently superior to intravenous Ganciclovir in preventing progression of retinitis. CMV is also implicated in two forms of anterior segment disease in immuno-competent adults, namely CMV anterior uveitis and CMV corneal endotheliitis.

The validity of clinical feature profiles for cytomegaloviral anterior segment infection.

BACKGROUND: Anterior segment cytomegalovirus (CMV) infection, which can be presented as anterior uveitis and corneal endotheliitis, has recently been reported in immunocompetent patients. We would like to access the validity of two presumed characteristic clinical profiles: profile 1, non-herpes simplex virus (HSV)/varicella zoster virus (VZV) corticosteroid-recalcitrant inflammatory ocular hypertensive syndrome (IOHS), and profile 2, corneal endotheliitis with specific coin-shaped keratic precipitates (KPs), that could be helpful in identifying CMV anterior segment intraocular infection. METHODS: Patients with either profile 1 or profile 2 or both were enrolled consecutively from the uveitis service in Chang Gung Memorial Hospital, Taoyuan, between January 1, 2006 and May 31, 2010. Diagnostic anterior chamber tapping was performed and followed by real-time quantitative polymerase chain reaction (PCR) to detect herpesviridae DNA including HSV I and II, VZV, CMV, and Epstein-Barr virus. RESULTS: Thirty-one eyes of 30 patients (21 males and nine females) were enrolled in this study. CMV DNA PCR was positive in 29 eyes of 28 patients (20 males and eight females). Nineteen of 20 eyes (19 patients) in profile 1 had positive CMV PCR. Ten of 11 eyes (11 patients) in profile 2 had positive CMV PCR. The positive predictive value of profile 1 and profile 2 was 94.7% and 90.9%, respectively. The positive predictive value of combining the two profiles was 93.3%. CONCLUSIONS: Non-HSV/ZVZ corticosteroid-recalcitrant IOHS and corneal endotheliitis with specific coin-shaped KPs could be used as the screening tool for CMV anterior segment intraocular infection.

Anterior segment manifestations of human immunodeficiency virus/acquired immune deficiency syndrome.

Ocular complications are known to occur as a result of human immunodeficiency virus (HIV) disease. They can be severe leading to ocular morbidity and visual handicap. Cytomegalovirus (CMV) retinitis is the commonest ocular opportunistic infection seen in acquired immune deficiency syndrome (AIDS). Though posterior segment lesions can be more vision-threatening, there are varied anterior segment manifestations which can also lead to ocular morbidity and more so can affect the quality of life of a HIV-positive person. Effective antiretroviral therapy and improved prophylaxis and treatment of opportunistic infections have led to an increase in the survival of an individual afflicted with AIDS. This in turn has led to an increase in the prevalence of anterior segment and adnexal disorders. Common lesions include relatively benign conditions such as blepharitis and dry eye, to infections such as herpes zoster ophthalmicus and molluscum contagiosum and malignancies such as squamous cell carcinoma and Kaposi's sarcoma. With the advent of highly active antiretroviral therapy, a new phenomenon known as immune recovery uveitis which presents with increased inflammation, has been noted to be on the rise. Several drugs used in the management of AIDS such as nevirapine or indinavir can themselves lead to severe inflammation in the anterior segment and adnexa of the eye. This article is a comprehensive update of the important anterior segment and adnexal manifestations in HIV-positive patients with special reference to their prevalence in the Indian population.

An increase in herpes simplex virus type 1 in the anterior segment of the eye is linked to a deficiency in NK cell infiltration in mice deficient in CXCR3.

In response to ocular herpes simplex virus type 1 (HSV-1) infection in mice, a rapid induction or increase in the local expression of chemokines, including CXCL10, is found. The present study investigated the role of the receptor for CXCL10, CXCR3, in the host response to corneal HSV-1 infection. Mice deficient in CXCR3 (CXCR3(-/-)) were found to have an increase in infectious virus in the anterior segment of the eye by day 7 postinfection. Coinciding with the increase, selective chemokines, including CCL2, CCL3, CCL5, CXCL9, and CXCL10, were elevated in the anterior segment of the HSV-1-infected CXCR3(-/-) mice. In contrast, there was a time-dependent reduction in the recruitment of natural killer (NK) cells (NK1.1(+)CD3(-)) into the anterior segment of CXCR3(-/-) mice. A reduction in NK cells residing in the anterior segment of mice following antiasialoGM1 antibody treatment resulted in an increase in infectious virus. No other leukocyte populations infiltrating the tissue were modified in the absence of CXCR3. Collectively, the loss of CXCR3 expression specifically reduces NK cell mobilization into the cornea in response to HSV-1.

Anterior segment complications of herpes zoster ophthalmicus.

TOPIC: The clinical features and management strategies for varicella-zoster virus (VZV) infections of the cornea, lids, and adnexa. CLINICAL RELEVANCE: Herpes zoster ophthalmicus (HZO) can result in a myriad of chronic and recurrent complications that may be sight threatening. Surgical intervention is the mainstay of treatment, and advancements in this area may lessen the complications of HZO if correctly implemented. METHODS: Literature review of pertinent topics, authors, and journals utilizing the National Institutes of Health PubMed service. RESULTS: A higher rate of treatment success for VZV-related complications was obtained when any preexisting ocular inflammation, increased intraocular pressure, lagophthalmos, dry eye, exposure, or neurotrophic keratitis was treated and under control before attempting ocular surgery. CONCLUSION: Options are available to manage ophthalmic complications of HZO and reduce the risk of treatment failure.

Targeted gene transfer to Schlemm's canal by retroperfusion.

The goal of the present study was to specifically modify protein expression in the resistance-generating region of the conventional outflow pathway, namely the inner wall of Schlemm's canal (SC) and the juxtacanalicular region of the trabecular meshwork, in perfused human anterior segments. Anterior segments from human cadaveric eyes were prepared for organ culture using standard techniques and were perfused at constant flow while recording pressure. After reaching a stable outflow facility within physiological limits, forward perfusion was stopped and a fluid-tight fence encircling the limbus was installed and filled with media containing an adenovirus encoding the lacZ reporter gene (either 2 x 10(6) or 6 x 10(6)PFU/ml). With the limbus submerged, pressure inside the chamber was lowered to -1 mmHg to facilitate reverse perfusion of virus into SC ("retroperfusion"). After 30-60 min at zero pressure (with some mixing), forward perfusion was restarted and continued for 5-7 days, after which anterior segments were fixed and processed for visualization of lacZ activity. Retroperfusion of nine anterior segments with adenovirus encoding a reporter gene did not appreciably alter baseline outflow facility (0.27+/-0.05 versus 0.29+/-0.08 microl/min per mmHg post-retroperfusion). Gross examination of outflow tissues showed focal distribution of lacZ activity around the circumference of SC, presumably near collector channels. In segments that were sequentially tilted during retroperfusion, the distribution of lacZ activity appeared more uniform. Sagittal histological sections showed lacZ activity in all portions of the conventional drainage tract, particularly cells in the resistance-generating region. Taken together, the results demonstrate that candidate protein expression by cells in the resistance-generating region of the conventional drainage pathway can be specifically modified by retroperfusion of adenovirus and examined for effects on outflow facility.

Ocular reactivation of MCMV after immunosuppression of latently infected BALB/c mice.

PURPOSE: The purpose of this study was to identify the site(s) of MCMV latency and reactivation in the eye. METHODS: Three months after supraciliary inoculation of 5 x 10(2) PFU of MCMV, BALB/c mice underwent immunosuppression with methylprednisolone and antibodies specific for CD4 T cells, CD8 T cells, and NK cells or with methylprednisolone alone. Control mice were infected but did not receive the immunosuppressants. After 2 or 3 weeks of immunosuppression, the mice were killed. Replicating virus and viral antigen were detected in the injected eyes, peripheral blood leukocytes (PBLs), and extraocular tissues by plaque assay and by staining for early antigen (EA) and beta-galactosidase (beta-gal), respectively. RESULTS: In latently infected, nonimmunosuppressed control mice, replicating-virus-and viral-antigen-positive cells were not detected in the injected eyes or extraocular tissues. After immunosuppression with methylprednisolone and antibodies, EA and beta-gal were detected, and replicating virus was recovered from the injected eye and from several extraocular sites, including liver, lungs, salivary glands, and kidneys. No virus was recovered from PBLs. beta-Gal- or EA-positive cells were observed in the RPE of most mice, and a few virus-infected cells were also observed in the nuclear layers and ganglion cells. Microscopic changes, including retinal folding and detachment, photoreceptor atrophy, macrophage infiltration, and a few EA-positive cytomegalic cells, were observed in the injected eye of immunosuppressed mice. CONCLUSIONS: After immunosuppression, MCMV reactivates in the injected eye and extraocular tissues, and RPE cells are the initial site of MCMV ocular reactivation in the eye. The timing of virus recovery from all sites suggests that MCMV observed in the injected eye is from in situ reactivation of virus and not from spread of virus from extraocular sites via infected PBLs.

Experimental and numerical studies of adenovirus delivery to outflow tissues of perfused human anterior segments.

PURPOSE: To investigate the efficacy of two different methods of adenoviral transfer of genes to trabecular meshwork (TM) and Schlemm's canal (SC) cells in cultured human anterior segments, using both experimental and numerical analyses. METHODS: Replication-deficient adenoviruses having coding sequence for beta-galactosidase (beta-gal) under the control of the cytomegalovirus promoter were used. Efficiency of gene transfer over time was verified by infecting cultured human TM cells and assaying for beta-gal activity. Next, ostensibly normal paired human eyes were prepared by standard techniques and perfused for 2 to 5 days to measure baseline facilities. Eyes were then infected by one of two methods: standard transcorneal puncture, or injection into a 1 mm diameter silastic segment of supply tubing immediately upstream of the perfusion dish. In both cases, the nominal total dose was 2 x 10(8) viral particles. Five days after viral injection, eyes were harvested and fixed, and wedges from each of four quadrants were examined histologically. Sections were assayed for beta-gal activity and/or stained with toluidine blue. In a parallel study, flow and viral transport within perfused anterior segments were numerically simulated for conditions that approximated those used experimentally. RESULTS: Eyes receiving viral particles by transcorneal injection showed variable levels of beta-gal activity and highly variable TM cellular morphology, ranging from excellent preservation to cellular lysis. Eyes receiving an equivalent viral dose via the supply tubing showed higher transfer efficiency, as judged by almost complete TM cell loss (indicative of viral toxicity) and intense extracellular beta-gal activity from the residual cytoplasm. At lower doses (1/3 to 1/1000 of that used in transcorneal injection) beta-gal activity was still present, while TM cell morphology was good at the lower viral doses. Computer modeling showed that the region beneath the cornea was nearly stagnant, and consequently virus introduced into this region by transcorneal injection was delivered very slowly to the TM. This caused the effective delivered viral dose to be low and sensitively dependent on the volume and shape of the transcorneally injected virus bolus. CONCLUSIONS: Injection of adenovirus into supply tubing led to consistent delivery of reporter gene and approximately 300-fold greater efficiency of gene transfer compared to the transcorneal injection method, and is therefore the preferred method for introducing viral particles into perfused anterior segments. These findings were consistent with computer modeling of flow and mass transport in perfused anterior segments. Although these quantitative results are specific to adenovirus, this general trend should hold for a wide range of perfused compounds.