Diagnostic and therapeutic challenges in acute retinal necrosis; an update.

Acute retinal necrosis (ARN) is a rare but severe ophthalmic pathology defined by panuveitis, retinal necrosis, and high rates of retinal detachment. ARN may lead to poor visual outcomes even if promptly diagnosed and treated. ARN may present with a wide spectrum of clinical findings compatible with panuveitis including anterior uveitis, scleritis, vitritis, necrotizing retinitis, occlusive vasculitis, and optic disc edema. The American Uveitis Society introduced clinical criteria in 1994 for the diagnosis of ARN, while more recent criteria have been proposed by the Standardization of Uveitis Nomenclature (SUN) Working Group and the Japanese ARN Study Group. Multimodal imaging is a valuable tool in evaluating patients with ARN, particularly in unusual cases, while utilizing retinal imaging and applying AI algorithms in these areas of clinical research could be highly beneficial. Over the last few years, significant progress has been made in achieving timely diagnosis and treatment. The precise identification of the viral cause in suspected ARN cases has been greatly enhanced by the advancements in PCR techniques and flow cytometry used for intraocular fluids. systemic (intravenous or oral) antivirals with adjunctive intravitreal antiviral therapy are recommended as first-line therapy to reduce disease severity, the risk of vision loss, and retinal detachment incidence. Although aciclovir was the first existing antiviral agent, at present many clinicians prefer high-dose valaciclovir orally or intravenous aciclovir combined with intravitreal foscarnet. Despite significant progress in diagnosing and treating ARN, further research is needed to improve visual outcomes in this challenging clinical condition.

An Unusual Manifestation of Brucella-Associated Uveitis in a Young Male Patient.

This is a unique case of retinoschisis as an ocular manifestation of brucellosis. A 38-year-old male presented with recurrent episodes of bilateral eye redness, predominately in his left eye. His visual acuity was not affected, and he did not report any other symptoms. On slit lamp examination, binocular Koeppe nodules of the iris and cells in the left anterior chamber were observed. Fundoscopy followed by meticulous multimodal imaging confirmed left inferior retinoschisis. The patient was diagnosed with panuveitis, and a series of laboratory examinations revealed positive anti-IgM Brucella antibodies. Ocular brucellosis can cause variable, atypical, and serious presentations, hence, early diagnosis is paramount to avoid complications.

Cytokines in Immune-mediated "Non-infectious" Uveitis.

Uveitis is a significant cause of ocular morbidity and accounts for approximately 5 - 10% of visual impairments worldwide, particularly among the working-age population. Infections are the cause of ~ 50% cases of uveitis, but it has been suggested that infection might also be implicated in the pathogenesis of immune-mediated "non-infectious" uveitis. There is growing evidence that cytokines (i.e., interleukins, interferons, etc.) are key mediators of immune-mediated "non-infectious" uveitis. For example, activation of the interleukin-23/interleukin-17 signalling pathway is involved in immune-mediated "non-infectious" uveitis. Studies in animal models have been important in investigating the role of cytokines in uveitis. Recent studies of clinical samples from patients with uveitis have allowed the measurement of a considerable array of cytokines even from very small sample volumes (e.g., aqueous and vitreous humour). The identification of complex patterns of cytokines may contribute to a better understanding of their potential pathogenetic role in uveitis as well as to an improved diagnostic and therapeutic approach to treat these potentially blinding pathologies. This review provides further insights into the putative pathobiological role of cytokines in immune-mediated "non-infectious" uveitis.

The large Hellenic Study of Uveitis: epidemiology, etiologic factors and classification.

PURPOSE: To analyse the demography, etiology, and classification of uveitis at a tertiary academic referral center. METHODS: An observational study was conducted on the archives of uveitic patients at the Ocular Inflammation Service of the Department of Ophthalmology at the University Hospital of Ioannina (Greece) from 1991 to 2020. This study aimed to investigate the epidemiological profile of patients, including their demographics and the main etiologic factors of uveitis. RESULTS: Out of 6191 cases with uveitis, 1925 were infectious, 4125 were non-infectious, and an overall of 141 masquerade syndromes were recorded. Among these cases, 5950 patients were adults, with a slight female predominance, while 241 were children (< 18 years old). Interestingly, 24.2% of cases (1500 patients) were associated with 4 specific microorganisms. Herpetic uveitis (HSV-1 and VZV/HZV) was the most common cause of infectious uveitis (14.87%), followed by toxoplasmosis (6.6%) and tuberculosis (2.74%). In 49.2% of non-infectious uveitis cases, no systematic correlation was found. The most frequent causes of non-infectious uveitis included sarcoidosis, white dot syndromes, ankylosing spondylitis, lens-induced uveitis, Adamantiades-Behçet disease, and idiopathic juvenile arthritis. Infectious uveitis was more common in the rural population, whereas non-infectious uveitis was more frequently recorded in the urban population CONCLUSIONS: Although our study was conducted on a predominantly white Caucasian population, it also reflects the effect of increasing immigration, improvements of diagnostic techniques, changes in referral patterns, and various actual changes in disease incidence.

Central Serous Chorioretinopathy: An Update on the Current State of Management.

Central serous chorioretinopathy (CSCR) is a relatively common retinal disorder that leads to central vision impairment, often with a high recurrence rate. The exact etiology and pathogenetic mechanisms have not been fully elucidated but are likely to be associated with hyperpermeability of the choroidal capillaries and failure of the retinal pigment epithelium (RPE), leading to serous detachment of the neurosensory retina. Multimodal imaging plays a critical role in the diagnostic approach and monitoring of CSCR. Fortunately, the natural course of the disease is usually self-limiting, with spontaneous resolution and total fluid reabsorption. However, some patients may exhibit recurrences or persistent subretinal fluid (chronic CSCR), leading to progressive and irreversible RPE atrophy or photoreceptor damage. Thus, to prevent permanent visual loss, individualized treatment should be considered. Recent developments in the diagnostic and therapeutic approach have contributed to better outcomes in patients with CSCR. More studies are required to improve our understanding of epidemiology, pathogenesis, diagnosis, and treatment, with a significant impact on the management of this challenging clinical entity. The purpose of this review is to summarize the current knowledge about the clinical features, diagnostic workup, and therapeutic approach of CSCR.

The Large Hellenic Study of Uveitis: Diagnostic and Therapeutic Algorithms, Complications, and Final Outcome.

PURPOSE: The purpose of this study is to present the diagnostic and therapeutic algorithms, complications, and final outcome in the management of uveitic patients at a tertiary academic referral center. DESIGN: Observational study. METHODS: Analysis of the archives of 6191 uveitic patients at the Ocular Inflammation Service of the Department of Ophthalmology of the University Hospital of Ioannina in Greece from 1991 to 2020. RESULTS: During the 30 years of the study, the diagnostic ability climbed from 45.43% (1991-1995) to 73.4% (2016-2020). This improvement was linked to several factors including the increase in the number of diagnostic paracenteses for the analysis of intraocular fluids, the range and quality of laboratory blood tests, the multimodal ophthalmic imaging, the proper use of nonophthalmic imaging, and the multidisciplinary approach. The degree of uveitis-related complications was related to the severity and cause of inflammation, the recurrence rate, inappropriate treatment, and the prolonged or initially inactive inflammation. The 3 most common complications included cataract, macular edema, and glaucoma. Apart from the modern treatments and surgical techniques, the 3-month preoperative control of inflammation played a critical role in the surgical outcomes. The percentage of patients with a successful outcome increased from 72% (2001-2005) to 90.50% (2016-2020). The center's experience, prompt referral, patient's compliance, and regular follow-ups are associated with a better outcome. The analysis of the results allowed the development of diagnostic and therapeutic algorithms. CONCLUSIONS: Developing diagnostic and therapeutic algorithms allows for the efficient management of uveitis, leading to better visual outcome and therefore a better quality of life.

Neovascular Glaucoma: An Update.

Neovascular glaucoma (NVG) is a severe type of secondary glaucoma with devastating complications and generally poor visual prognosis. NVG is defined by the development of pathological neovessels over the iris and the iridocorneal angle that can block the outflow of aqueous humor, causing elevation of intraocular pressure (IOP). The pathogenesis of NVG is, in most cases, associated with ischemia of the posterior segment, which is most frequently associated with proliferative diabetic retinopathy or central retinal vein occlusion. The advanced stages of NVG are by iris and angle neovascularization, angle, and extremely high IOP, accompanied by ocular pain and poor vision. The therapeutic approach of NVG is based on the reduction of retinal ischemia by panretinal photocoagulation. Intravitreal anti-VEGF administration can contribute to the regression of neovascularization, and topical and systemic medications may be necessary for IOP control. However, if medical treatment with these agents is not enough, surgical procedures may be required to lower IOP and prevent glaucomatous optic neuropathy. Early and prompt diagnosis, with identification of the underlying etiology, can improve IOP control and final visual outcome. The aim of this study is to review current knowledge of the pathogenesis and management of NVG.

A novel case of Raoultella planticola - associated acute dacryocystitis.

This study aims to report an acute dacryocystitis associated with Raoultella planticola infection. The patient's medical records and laboratory were thoroughly assessed. A thorough literature search was performed in PubMed database. An additional search was made in Google Scholar to complete the collected items. This is the first recorded case of acute dacryocystitis attributed to Raoultella planticola infection. A limited number of studies has related this pathogen with conjunctivitis. Acute dacryocystitis on rare occasions can also be caused by atypical organisms. Swabs must be obtained and patients must be started on empirical treatment while waiting for the laboratory results.

Ocular toxoplasmosis: a review of the current diagnostic and therapeutic approaches.

PURPOSE: This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up and therapeutic approach of ocular toxoplasmosis focusing mainly on the postnatally acquired form of the disease. METHODS: A meticulous literature search was performed in the PubMed database. A supplementary search was made in Google Scholar to complete the collected items. RESULTS: Ocular toxoplasmosis is one of the most frequent infectious etiologies of posterior uveitis. It typically presents with retinochoroiditis. Setting an accurate diagnosis depends to a considerable degree on detecting characteristic clinical characteristics. In addition to the evaluation of clinical features, the diagnosis of toxoplasmosis relies at a large degree on serologic testing. The detection of the parasite DNA in the aqueous or vitreous humor can provide evidence for a definitive diagnosis. The current mainstay for the treatment, if necessary, is the use of oral antibiotic with systemic corticosteroids. Recent evidence suggests other therapeutic approaches, such as intravitreal antibiotics can be used. CONCLUSION: Recent developments in the diagnostic and therapeutic approach have contributed to preventing or limiting vision loss of patients suffering from ocular toxoplasmosis. Further studies are required to provide a better understanding of epidemiology, pathogenesis, diagnosis, and treatment with a significant impact on the management of this challenging clinical entity.

Pathophysiological Aspects of Ocular Toxoplasmosis: Host-parasite Interactions.

PURPOSE: This review aims to present the state of the art to understand the pathophysiology of ocular toxoplasmosis (OT), providing further foundations that would help to improve the future treatment and prognosis of this potentially blinding disease. METHODS: A thorough literature search was performed in PubMed database. An additional search was made in Google Scholar to complete the collected items. RESULTS: Toxoplasma gondii ocular infection is one of the most frequent causes of posterior uveitis. Despite the ocular barriers, the parasite reaches the eye through different mechanisms. Once inside, it remains encysted livelong within the retina, and recurrences cannot be completely avoided. The complexity of host-parasite interactions, leading to the success of this parasite, encompasses host factors such as genetic predisposition, immune status, and age; and parasite factors such as strain diversity, virulence, phylogenetic origin, and geographical distribution. These factors influence the clinical presentation, course, and progression of the disease. Additional elements, such as pregnancy, eating behavior, and environmental, social, and cultural factors may also contribute to this complex balance. CONCLUSIONS: The host-parasite interaction in OT is a complex and multifactorial relationship, with the parasite always on the driving edge of the game. There are still multiple incompletely understood fields to be investigated. Future research would permit further insight into the immune-biology of the parasite and recognition of the host-parasite interplay to improve the diagnostic and management performance.

Spirochetal uveitis: Spectrum of clinical manifestations, diagnostic and therapeutic approach, final outcome and epidemiological data.

PURPOSE: Analysis of cases with spirochetal uveitis related to spirochetes in a tertiary referral academic center. METHODS: Retrospective study of patients diagnosed with uveitis attributed to Treponema pallidum, Leptospira spp. and Borrelia burgdorferi from June 1991 until December 2019. RESULTS: A total of 57 cases of spirochetal uveitis (22 patients with T. pallidum, 26 with Leptospira spp., and 9 with B. burgdorferi) that consisted 1% of the overall number of uveitics were recorded. All these cases presented with a wide spectrum of clinical presentations (anterior uveitis, posterior uveitis, panuveitis, vasculitis, papillitis, and in some rare cases concomitant posterior scleritis). The treatment included mainly penicillin or doxycycline, while corticosteroids were administered systematically in some cases with Borrelia or Leptospira infection. The final visual outcome was favorable (> 6/10 in Snellen visual acuity) in approximately 76% of our patients. CONCLUSION: Despite being rare, spirochetal uveitis can be detrimental for the vision and must always be included in the differential diagnosis.

Four common diseases causing sudden blindness or death in the eye emergency department.

Neuro-ophthalmological emergency disorders typically present with symptoms of visual loss, diplopia, ocular motility impairment or anisocoria. The ocular manifestations of these disorders are sometimes indicative of a more serious global neurology disease rather than an isolated ocular disease. The aim of this review is to highlight four important neuro-ophthalmological emergency disorders that must not be missed by an ophthalmologist. These include acute painful Horner's syndrome, painful cranial nerve III palsy, giant cell arteritis and transient ischaemic attack with amaurosis fugax. The delayed diagnosis of these clinical entities puts the patient at risk of blindness or death. Therefore, prompt diagnosis and management of these conditions are essential. This can be acquired from understanding the main signs and symptoms of the disease presentation together with a high index of suspicion while working at a busy eye emergency department.

Molecular Analysis of Dirofilaria repens Isolates from Eye-Care Patients in Greece.

PURPOSE: Human ocular dirofilariasis is a zoonotic disease caused by several species of filarioid helminths of the genus Dirofilaria. The aim of this study was to further re-examine five preserved specimens previously isolated from patients with ocular dirofilariasis by molecular means. METHODS: Four of the examined helminths had been stored in unbuffered formaldehyde solution for more than eight years; whereas, the fifth helminth was stored in ethanol buffer for more than two years. For the four specimens stored in formaldehyde, different methods of DNA recovery and amplification were applied and investigated for their efficiency in DNA extraction and PCR amplification. However, the DNA extraction and PCR amplification were successful only for the ethanol-preserved helminth. RESULTS: The genetic identification of the ethanol-preserved specimen as Dirofilaria repens (D. repens) and its phylogenetic position based on the analysis of mitochondrial 12S ribosomal RNA, nuclear 18S ribosomal RNA and mitochondrial cytochrome c oxidase subunit one sequences are reported in the present paper. To our knowledge, these are the only deposited sequences related to D. repens that have been isolated in Greece. CONCLUSIONS: Routine laboratory diagnosis is based on phenotypic characteristics of the helminthic parasites, but more accurate diagnosis requires molecular identification. Although the specimens preserved in formalin buffers may be a potential source for the enrichment of parasite genome databases, the DNA recovery of such samples is a challenging task.

Antigen-presenting cells in ocular surface diseases.

PURPOSE: To review the role of antigen-presenting cells (APC) in the pathogenesis of ocular surface diseases (OSD). METHODS: A thorough literature search was performed in PubMed database. An additional search was made in Google Scholar to complete the collected items. RESULTS: APCs have the ability to initiate and direct immune responses and are found in most lymphoid and non-lymphoid tissues. APCs continuously sample their environment, present antigens to T cells and co-ordinate immune tolerance and responses. Many different types of APCs have been described and there is growing evidence that these cells are involved in the pathogenesis of OSD. OSD is a complex term for a myriad of disorders that are often characterized by ocular surface inflammation, tear film instability and impairment of vision. CONCLUSIONS: This review summarizes the current knowledge concerning the immunotopographical distribution of APCs in the normal ocular surface. APCs appear to play a critical role in the pathology of a number of conditions associated with OSD including infectious keratitis, ocular allergy, dry eye disease and pterygium.

The role of tele-ophthalmology in diabetic retinopathy screening.

Diabetic retinopathy (DR) is the leading cause of legal blindness in the United States. Considering the increasing incidence of DR, it is extremely important to detect the most cost-effective tools for DR screening, so as to manage this surge in demand and the socioeconomic burden it places on the health care system. Despite the advances in retinal imaging, analysis techniques are still superseded by expert ophthalmologist interpretation. Teleophthalmology presents an immense opportunity, with high rates of sensitivity and specificity, to manage the steadily increasing demand for eye care of patients with diabetes, but challenges remain in the delivery of practical, viable, and clinically proven solutions.

Posterior Scleritis as a Paraneoplastic Syndrome in Colon Cancer: A Case Report

This study presents a rare case of unilateral posterior scleritis as an ophthalmic manifestation of a paraneoplastic syndrome. A 61-year-old man presented to our department complaining of gradual worsening of vision in his left eye. Visual acuity was 10/10 and 3/10 in his right and left eye, respectively. He also mentioned that he experienced posterior ocular pain while sleeping at night, but was otherwise asymptomatic. His past ophthalmic and medical history were clear. A thorough clinical, imaging (fundus photography, optical coherence tomography, fluorescein angiography, and B-scan), and laboratory investigation was carried out. A diagnosis of posterior scleritis was made, but no obvious cause or underlying disease was identified even after a thorough systematic assessment. Regular follow-up within the next few months did not reveal any further pathological findings. Finally, 6 months after the initial presentation, the patient was diagnosed with colon cancer. Posterior scleritis can present as an ophthalmic manifestation of a paraneoplastic syndrome in patients with an underlying malignancy, even months before the presentation of systemic symptoms and diagnosis of the underlying disease. In conclusion, in patients (especially older adults) with posterior scleritis, the possibility of a malignant neoplasia must not be ignored or underestimated (paraneoplastic syndrome).

The physiologic and pathologic effects of pregnancy on the human visual system.

Pregnancy is a normal state of physiological stress that induces significant changes in the human body, some of which can potentially affect the visual system. The pregnant state may exacerbate pre-existing ocular disorders (i.e. diabetic retinopathy or central serous retinopathy). Moreover, other systemic conditions related to pregnancy can induce ophthalmic disorders affecting the retina and the choroid, some of which are of acute nature. Increasing awareness and improving collaboration between ophthalmologists, obstetricians and internists can play a pivotal role in the management of complex conditions during pregnancy. Special attention should be given while prescribing medications or deciding about other diagnostic or therapeutic techniques. The purpose of this review is to summarise the physiologic and pathologic effects of pregnancy in the eyes, highlighting the most acute clinical entities that may be threatening for the vision or even the life of the mother and her baby.

Primary vitreoretinal lymphoma.

Primary vitreoretinal lymphoma (PVRL) is a rare ocular lymphoid malignancy, which consists a subset of primary central system lymphoma (PCNSL) and the most common type of intraocular lymphoma. The involvement of eyes is estimated to be approximately 20% of PCNSL, but the brain involvement may be up to 80% of PVRL. Typically, PVRL is a high grade B-cell malignancy of the retina and needs to be assorted from choroidal low-grade B-cell lymphomas. Very often PVRL masquerades and can be erroneously diagnosed as chronic uveitis, white dot syndromes or other neoplasms. Establishing an accurate diagnosis may involve cytology/pathology, immunohistochemistry, flow cytometry, molecular pathology and cytokine profile analysis. There is inadequate information about PVRL's true incidence, ethnic/geographical variation and pathogenetic mechanisms. The therapeutic approach of PVRL involves aggressive chemotherapy and radiation therapy. Although PVRL tends to have a good response to the initial treatment, the prognosis is poor and the survival restricted due to the high relapse rates and CNS involvement.

Bartonella henselae- and quintana-associated uveitis: a case series and approach of a potentially severe disease with a broad spectrum of ocular manifestations.

PURPOSE: To evaluate the clinical manifestations of intraocular inflammation associated with Bartonella infection and describe the assessment and management of patients with cat-scratch disease (CSD). METHODS: This is a retrospective review of the clinical records of patients diagnosed with Bartonella henselae and Bartonella quintana intraocular inflammation from 2011 to 2018 in the Department of Ocular Inflammations and Infections of the University Eye Clinic of Ioannina (Greece). An analysis of the current literature concerning Bartonella-related intraocular infections was also carried out. RESULTS: This is a retrospective study of 13 patients (7 males and 6 females) with a mean age of 39.2 years that were diagnosed with unilateral intraocular inflammation, except one case with bilateral affection, attributed to Bartonella (either henselae or quintana). Twelve (12) patients (92.3%) had a positive history of traumatic cat contact. The main ocular clinical findings with regard to the type of uveitis included neuroretinitis in 5 eyes (38.5%), vasculitis in 3 eyes (23.1%), iridocyclitis in 2 eyes (15.4%), intermediate uveitis in 2 eyes (15.4%), posterior uveitis in 1 eye (7.7%), panuveitis in 2 eyes (15.4%), retinochoroiditis in 2 eyes (15.4%), vitritis in 1 eye (7.7%), peripheral choroidal granuloma in 1 eye (7.7%). Immunoglobulin (Ig) G was positive in all cases. All patients were treated with antibiotics (mainly rifampicin, doxycycline and azithromycin). The visual acuity was noted to be improved in all patients after treatment, but some of them experienced disturbing complications. CONCLUSION: CSD may manifest with various ocular pathological findings. Taking into consideration the increasing frequency of infections by B. henselae and B. quintana, clinicians should always incorporate CSD in the differential diagnosis of such presentations of uveitis. Educating vulnerable groups (children, immunosuppressed, etc.) and also general population, the appropriate preventing measures can contribute in limiting the risk of infection.