Adult cytomegalovirus inclusion retino-uveitis

Rapid regression of cystoid macular edema associated with cytomegalovirus retinitis in adult acute myeloid leukemia by intravitreal methotrexate combined with oral valganciclovir: A case report with comparison of binocular outcome

Cytomegalovirus (CMV) retinitis is a late complication of organ and hematopoietic stem cell transplant, the risk of which depends on the degree of immunosuppression. With the institution of preemptive ganciclovir therapy early after transplant, most patients survive episodes of life-threatening CMV infection during the early months (usually the first 3 months) after transplant and hence late onset of CMV disease, such as CMV retinitis, is being recognized more frequently. Direct involvement of the macula or optic head remains the leading cause of visual loss in patients with CMV retinitis, but there are few studies investigating the management of this condition.

Herein, we present the case of 28-year-old man who had acute myeloid leukemia and developed CMV retinitis with bilateral cystoid macular edema and optic swelling in the right eye 6 months after bone marrow transplant. He received treatment with intravitreal methotrexate in the right eye in combination with oral valganciclovir. Visual acuity improved 1 month after four weekly injections of intravitreal methotrexate 400 µg/0.1 mL. Resolved disc swelling and regression of macular edema were also observed. By comparing binocular outcome, we present our findings and discuss the possible efficacy and safety of this treatment with respect to regression of anatomical damage and improvement in visual acuity.

Cytomegalovirus Uveitis with Hypopyon Mimicking Bacterial Endophthalmitis

We report an 83-year-old immune-competent female with unilateral endophthalmitis extraordinarily caused by cytomegalovirus (CMV). Since she was suspected of suffering possible bacterial endophthalmitis, she was referred to our hospital. At the first visit, hypopyon in the anterior chamber and the opacity of vitreous body were observed in the left eye. The best-corrected visual acuity (BCVA) of the left eye was counting fingers and the intraocular pressure (IOP) was 20 mmHg. Bacterial and fungus culture of the aqueous humor revealed no infection. However, the density of corneal endothelial cell was less than the measurable range and CMV was detected by PCR of the aqueous humor. She was immune-competent and the data indicated neither systemic infections nor diseases. Systemic valganciclovir and corticosteroid were administered. After that, hypopyon in the anterior chamber and the opacity of vitreous body of the left eye were improved, and the BCVA of the left eye was 20/200 one year after the first visit. However, the inflammation of the anterior chamber recurred accompanied by elevated IOP after the discontinuance of administering valganciclovir. CMV-induced uveitis accompanied with hypopyon is quite rare. Therefore, it can be easily misdiagnosed as bacterial endophthalmitis.

Fundus autofluorescence changes in cytomegalovirus retinitis

PURPOSE

The purpose of this study was to describe fundus autofluorescence imaging features of cytomegalovirus (CMV) retinitis and to correlate fundus autofluorescence features with clinical activity.

METHODS

A retrospective case series was undertaken to evaluate nine eyes of six patients with active CMV retinitis. Patients were evaluated with a comprehensive ophthalmic examination, fundus autofluorescence imaging, and fundus photography. Oral valganciclovir, intravitreal ganciclovir, intravitreal foscarnet, or an ganciclovir implant was administered as clinically indicated.

RESULTS

In all nine eyes with active CMV retinitis, a hyperautofluorescent signal on fundus autofluorescence imaging was correlated spatially with the border of advancing CMV retinitis. Stippled areas of alternating hyperautofluorescence and hypoautofluorescence were observed in regions of retinal pigment epithelium atrophy from prior CMV retinitis. In three eyes with subtle CMV reactivation, a hyperautofluorescent border was helpful in the detection and localization of active CMV retinitis. In another patient, diffuse, punctate hyperautofluorescence after intravitreal ganciclovir and foscarnet was a concern for medication-related toxicity.

CONCLUSION

Fundus autofluorescence imaging was valuable in highlighting areas of active CMV retinitis in all patients in this series, including two patients with subtle clinical features. Fundus autofluorescence may be useful as an adjunctive imaging modality for the detection of CMV activity and aid in our understanding of the structural changes during episodes of CMV retinitis.

Cytomegalovirus as a Cause of Anterior Uveitis in Immunocompetent Patients

PURPOSE

To describe 7 cases of unilateral, chronic and/or recurrent anterior uveitis caused by cytomegalovirus (CMV) in immunocompetent patients; to identify specific ophthalmologic characteristics; and to evaluate the clinical effect of valganciclovir treatment.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Immunocompetent patients (n = 7) with a history of chronic and/or recurrent unilateral anterior uveitis and a positive analysis for either CMV-DNA and/or antibodies against CMV in their aqueous humor (Goldmann-Witmer coefficient > 3).

METHODS

Full ophthalmologic examination, anterior chamber fluid analysis, serologic examination, and systemic evaluation. Treatment modalities included topical steroids, topical and/or systemic antiglaucoma medications, glaucoma surgery, and systemic valganciclovir.

MAIN OUTCOME MEASURES

Visual acuity, inflammation, and intraocular pressure (IOP).

RESULTS

Chronic unilateral anterior uveitis was seen in 6 patients, whereas recurrent uveitis was observed in 1. Additional findings consisted of slight iris atrophy and secondary glaucoma (n = 3), secondary glaucoma without iris abnormalities (n = 3), and a slightly elevated IOP without iris abnormalities (n = 1). Examinations of the aqueous humor by polymerase chain reaction demonstrated CMV-DNA in 6 patients and were negative for other herpes viruses in all. Goldmann-Witmer coefficients were strongly positive in 4 out of 5 patients. Other laboratory investigations were within normal limits. No other causes for uveitis were identified. Because of the insufficient effect of topical steroids and antiglaucoma medications, 5 patients were treated with additional oral valganciclovir with good clinical response in terms of uveitis activity and IOP. Discontinuation of valganciclovir in 1 patient resulted in a prompt recurrence of uveitis activity.

CONCLUSIONS

Cytomegalovirus may cause a chronic and/or recurrent anterior uveitis in otherwise healthy patients. Iris atrophy and glaucoma may accompany it, but an inflammatory reaction in the anterior chamber may be the only sign. Aqueous humor analysis is of the utmost importance in differentiating between CMV and other herpes viruses and in making a definite diagnosis in chronic anterior uveitis. Valganciclovir may be very effective in treating CMV anterior uveitis, but its exact role can only be determined in larger studies with a longer follow-up.

Transient vitreous inflammatory reactions associated with combination antiretroviral therapy in patients with AIDS and cytomegalovirus retinitis

PURPOSE

To report the observation that a transient vitreous inflammatory reaction may develop in the eyes of patients with acquired immunodeficiency syndrome (AIDS), cytomegalovirus retinitis, and an increased CD4+ T-lymphocyte count during treatment with antiretroviral therapy including a protease inhibitor.

METHODS

We reviewed the medical records of eight patients with AIDS and cytomegalovirus retinitis who developed vitreous inflammatory reactions greater than those usually seen with this disease.

RESULTS

Vitreous inflammatory reactions obscured the view of the posterior pole in all patients. No iris nodules, synechiae, glaucoma, or cystoid macular edema were observed. Six patients had unilateral cytomegalovirus retinitis, and, in each, the inflammation occurred only in the eye with cytomegalovirus retinitis. The vitreous inflammatory reactions were associated with clinically inactive cytomegalovirus retinitis in six patients, with disease reactivation in one patient, and were present at diagnosis of active disease in one patient. Cytomegalovirus retinitis has not recurred in any of these patients since their episodes of vitreous inflammation. Vitreous inflammation developed in all eight patients after a substantial increase in CD4+ T-lymphocyte counts caused by combination antiretroviral therapy. Five patients had CD4+ T-lymphocyte counts of greater than 100 cells per microl at the time the vitreous inflammatory reaction developed. No other causes of uveitis were found.

CONCLUSIONS

Patients with AIDS and cytomegalovirus retinitis may develop transient intraocular inflammation associated with combination antiretroviral therapy. We believe that this inflammation reflects an improved immune response against cytomegalovirus.

Visual loss in cytomegalovirus retinitis caused by cystoid macular edema in patients without the acquired immune deficiency syndrome

PURPOSE

Although serous macular exudation has been described in patients with the acquired immune deficiency syndrome (AIDS) with active cytomegalovirus (CMV) retinitis, cystoid macular edema (CME) is not encountered in this clinical setting. In contrast to these findings, we describe vision loss due to CME occurring in immunosuppressed patients without AIDS treated for CMV retinitis.

METHODS

Three patients (four eyes) with systemic immunodeficiency presenting with vision loss underwent ophthalmologic examination, including fundus photography and fluorescein angiography. Systemic evaluation was performed to establish the etiology of immunodeficiency and to rule out human immunodeficiency virus infection. Patients were treated with topical corticosteroid and nonsteroidal anti-inflammatory medications for CME.

RESULTS

All patients had severe generalized immune deficiency, related either to drug-induced immunosuppression or primary immunodeficiency. Laboratory studies confirmed the presence of systemic CMV infection. Affected eyes had mild reduction of central vision (range, 20/40 to 20/60). Three of four affected eyes had resolving CMV retinitis outside the posterior pole with mild panuveitis. These eyes showed CME on clinical examination and fluorescein angiography. The CMV lesions regressed after reduction of immunosuppressive agents or after systemic antiviral treatment. Response of CME to topical anti-inflammatory medication was variable.

CONCLUSIONS

Cystoid macular edema can occur in the setting of resolving CMV retinitis in patients with immunodeficiency other than AIDS. This entity is distinct from serous macular exudation, which can occur in patients with AIDS with active CMV retinitis involving the posterior pole. The disparity between patients with and without AIDS in the development of CME may be important in understanding the pathogenesis of CME.

Anterior segment findings in AIDS patients with cytomegalovirus retinitis

BACKGROUND

Anterior segment findings in AIDS patients presenting with cytomegalovirus (CMV) retinitis have not been specifically addressed in the American literature.

METHODS

Our study evaluated 21 AIDS patients with CMV retinitis.

RESULTS

Nineteen (90%) of these patients exhibited corneal endothelial deposits concurrent with CMV retinitis. The endothelial deposits were microscopic, opaque, linear flecks arranged in a reticular-like fashion. Of 42 eyes evaluated, 32 (76%) demonstrated active CMV retinitis. Corneal endothelial deposits were noted in 26 (81%) of the 32 eyes with retinitis. These corneal endothelial deposits were absent in the eyes which did not have CMV retinitis.

CONCLUSION

Meticulous examination of the retina of an HIV-positive or AIDS patient who presents with reticularly arranged, linear, flecked corneal endothelial deposits should be performed to ensure that the diagnosis of CMV retinitis can be ruled out.

Retinitis in euthymic mice following inoculation of murine cytomegalovirus (MCMV) via the supraciliary route

Cytomegalovirus (CMV) retinitis is the most frequent infectious ocular complication of the acquired immune deficiency syndrome (AIDS). Currently, there are few animal models to study the virologic and immunologic factors which contribute to the pathogenesis of CMV retinitis. In these experiments, 1-2 X 10(4) PFU of murine cytomegalovirus (MCMV) was inoculated into the supraciliary space of BALB/c mice. Within three days of inoculation, moderate iridocyclitis was observed which progressed to necrosis of the ciliary body by day 14. Approximately 60% of the mice developed typical retinitis characterized by virus-infected cytomegalic cells in the retina and retinal pigment epithelium, focal retinal infiltrates, transition zones between uninvolved and involved retina, and optic neuritis. The remaining animals exhibited atypical retinitis characterized by non-specific retinal inflammation in the absence of obvious viral infection. This murine model of CMV retinitis shares some features with retinitis observed in AIDS patients with CMV retinitis and may be useful to evaluate the efficacy of immunologic and/or pharmacologic treatment strategies for CMV retinitis.

Cytomegalovirus retinitis

Cytomegalovirus retinitis is a frequent and serious complication of various conditions, including diseases characterized by impaired immunity, such as the acquired immunodeficiency syndrome. Due to recent advances in the treatment of cytomegalovirus retinitis, accurate diagnosis and management have become increasingly important. In this review, the authors present the epidemiology, clinical features, diagnostic testing, treatment with complications, and prognosis of cytomegalovirus retinitis. A differential diagnosis is presented and the characteristic ocular lesions are illustrated.

Treatment of cytomegalovirus retinitis with ganciclovir (9-[2-hydroxy-1-(hydroxymethyl) ethoxymethyl] guanine (BW B759U)

Six patients (11 eyes) with virologically confirmed cytomegalovirus (CMV) retinitis involving the posterior pole of the eye were treated with a new drug, ganciclovir. Treatment with intravenous ganciclovir consistently halted progression of retinitis and produced improvement in measures of visual function. However, within three weeks after cessation of therapy renewed CMV activity and worsening of visual function were observed in most cases. Maintenance therapy with ganciclovir extended the period of remission from CMV retinitis.

Active cytomegalovirus particles in the eyes of an AIDS patient being treated with 9-[2-hydroxy-1-(hydroxymethyl) ethoxymethyl] guanine (Ganciclovir)

The eyes of an AIDS patient with cytomegalovirus (CMV) retinitis and pneumonitis who died while receiving maintenance therapy with the antiviral agent 9-[2-hydroxy-1-(hydroxymethyl) ethoxymethyl] guanine (Ganciclovir) were obtained for pathological examination. While under treatment the patient had significant improvement but not complete regression of retinitis. Electron microscopic and immunofluorescent techniques revealed cytomegalovirus particles in the retina, sclera, iris, and ciliary body. These findings are consistent with a virostatic type of inhibition of CMV by this agent. They also suggest that CMV involvement in the eye and other organs may be more widespread than is clinically apparent in AIDS patients.

Uveitis: a strategy for diagnosis

Uveitis may be the first presentation of a wide variety of underlying ocular and systemic diseases. It is important for the ophthalmologist to make a specific diagnosis in order to instigate specific therapy and give an accurate prognosis. The ability to recognise the clinical patterns of uveitis and to initiate appropriate investigations should form the basis of the ophthalmologist's management of the condition. To this end, we have considered uveitis under four major patterns of presentation--anterior uveitis, intermediate uveitis, posterior uveitis, and panuveitis--with subclasses within each of these four groups. We have outlined both the investigations which facilitate diagnosis of the possible underlying causes of inflammation and the interpretation of the results of such investigations.

A case of frosted branch angiitis

We report a case of frosted branch angiitis in a 16-year-old-girl. She noted a sudden and severe visual disturbance in both eyes, without other systemic symptoms. Diffuse retinal oedema and unusual sheathing of retinal veins were characteristic in both fundi. Fluorescein angiography showed no occlusion of the sheathed retinal veins, but some paravenous extravasation of dye was found in the late phase. With high doses of systemic corticosteroids her fundi and visual acuity improved greatly, though the vessels continued to show severe narrowing. At three months the pattern visually evoked cortical potentials were found to be normal, while flash electroretinograms were absent. No systemic abnormality has been found to explain the aetiology of this condition.

Prevalence, pathophysiology, and treatment of rhegmatogenous retinal detachment in treated cytomegalovirus retinitis

Seventeen patients with the acquired immune deficiency syndrome and cytomegalovirus retinitis were treated with the antiviral drug ganciclovir (9-[1,3-dihydroxy-2-propoxy-methyl]-guanine, DHPG). Eight eyes of five patients developed rhegmatogenous retinal detachment after initiation of treatment. Multiple breaks in areas of peripheral, healed, atrophic retina accounted for the detachments. All seven eyes that underwent surgery had extensive retinal detachments that were reattached with vitrectomy and silicone oil. Retinotomy and retinal tacks were necessary in two cases that were complicated by severe proliferative vitreoretinopathy. In the fellow eye of one patient, laser treatment was used prophylactically to wall off a peripheral patch of healed retinitis. Endoretinal biopsies and culture were taken in five eyes; evidence of persistent cytomegalovirus was seen in two cases despite concurrent and clinically effective antiviral therapy.

Antiviral therapy with ganciclovir for cytomegalovirus retinitis and bilateral exudative retinal detachments in an immunocompromised child

A child with bilateral cytomegalovirus (CMV) retinitis, vitritis, and exudative retinal detachments, who was in remission from stage IV neuroblastoma and status post-chemotherapy and autologous bone marrow transplantation, was treated with ganciclovir. The drug is a new acyclic nucleoside antiviral drug with potent antiCMV activity. There was bilateral retinal reattachment, clearing of vitritis and regression of retinal exudates and hemorrhages, with concomitant resolution of viral shedding in urine and blood, on ganciclovir 7.5 mg/kg per day. There was recurrence of exudative detachments, vitritis and retinitis when the dose was reduced to 2.5 mg/kg per day, and regression of these findings when the dose was again increased to 7.5 mg/kg per day. Despite continued therapy at this dose, a relapse occurred. When the dose of drug was doubled to 15 mg/kg per day, there initially was a partial therapeutic response, followed by a subsequent relapse. No further response was seen when the dose was increased to 19.5 mg/kg per day. This patient was treated with ganciclovir for a total of 192 days. No adverse reactions to ganciclovir were seen. On the last day of drug administration, there were persistent bilateral exudative retinal detachments and progressive optic nerve head involvement with optic disc pallor, despite quiescence of the retinitis.

The acute retinal necrosis syndrome. Possible herpes simplex retinitis

The acute retinal necrosis (ARN) syndrome is a severe necrotic peripheral retinitis with vasculitis and vitritis. It attacks healthy people and carries a poor visual prognosis. Five patients with ARN were seen. Two showed interesting clinical features. One patient developed the ARN syndrome in both eyes but with a 14-year hiatus separating the two episodes, each being preceded by an infectious illness. A second patient had a possible recurrence of the ARN syndrome in the same eye, one year after the original episode. Each episode was preceded by an upper respiratory infection and ipsilateral vesicular skin lesions on the face. Biopsy of one lesion yielded herpes simplex virus (HSV) in culture. These associations, although not definitive, do lend support to the hypothesis that HSV may be the cause of the ARN syndrome.

Bilateral acute retinal necrosis (BARN). Identification of the presumed infectious agent

We describe histopathologic features of an enucleated eye of a patient suffering bilateral acute retinal necrosis (BARN). Retinal tissue was found focally degenerated, and the choroid massively enlarged by lymphoid-like agranular cells. An association of the disease with a viral infection could be demonstrated by (a) the presence of virus particles of the herpesvirus type in retinal tissue, (b) the transmission of the infected principle to human embryo fibroblast cultures, and (c) the visualization of CMV-antigens by immunofluorescence microscopy in such infected cultures. Slow growth of the virus in vitro and the presence of CMV-antigens after infection indicate that the herpesvirus involved in BARN was of the type CMV. On the basis of these findings we propose a guideline for therapy.

Cyclosporin A treatment for chronic uveitis associated with retinitis

A chronic bilateral non-granulomatous uveitis triggered by a chlamydial infection developed in a patient with HLA-B 27. Cyclosporin A was administered as an ultimate remedy. It had a rapid curative effect against the inflammation. Probable cytomegalovirus (CMV) retinitis, however, was observed 2 months after the onset of this treatment. Retinitis healed after discontinuation of Cyclosporin A therapy.

Acute retinal necrosis

We treated 2 patients with unilateral acute retinal necrosis in association with uveitis. The disorder began as anterior uveitis, secondary glaucoma, and retinal vasculitis, and then developed into retinal necrosis within a few months. The aetiology was obscure and the appropriate treatment debatable. We also review reports of patients showing the same clinical characteristics, termed Kirisawa-type uveitis and bilateral acute retinal necrosis, and believe the disorders to be identical.

Cytomegalovirus retinitis: a manifestation of the acquired immune deficiency syndrome (AIDS)

Two homosexual males with the "gay bowel syndrome' experienced an acute unilateral loss of vision. Both patients had white intraretinal lesions, which became confluent. One of the cases had a depressed cell-mediated immunity; both patients ultimately died after a prolonged illness. In one patient cytomegalovirus was cultured from a vitreous biopsy. Autopsy revealed disseminated cytomegalovirus in both patients. Widespread retinal necrosis was evident, with typical nuclear and cytoplasmic inclusions of cytomegalovirus. Electron microscopy showed herpes virus, while immunoperoxidase techniques showed cytomegalovirus. The altered cell-mediated response present in homosexual patients may be responsible for the clinical syndromes of Kaposi's sarcoma and opportunistic infection by Pneumocystis carinii, herpes simplex, or cytomegalovirus.

The acute retinal necrosis syndrome. Part 2: Histopathology and etiology

The acute retinal necrosis syndrome is manifested by diffuse uveitis, vitritis, retinal vasculitis, and acute necrotizing retinitis (see Part 1). We studied the histopathology and electron microscopic findings of an eye enucleated from a 67-year-old man with typical acute retinal necrosis. Histology showed profound acute necrosis of the retina, retinal arteritis, and eosinophilic intranuclear inclusions in retinal cells. Electron microscopy demonstrated a herpes group virus in all layers of affected retina. The implications of these findings for antiviral and other treatments are discussed.

Cytomegalovirus retinitis in a young homosexual male with acquired immunodeficiency

A case is reported of histopathologically documented CMV retinitis. It is part of a recently appreciated syndrome in young homosexual men, in which cellular immune deficiency has been documented and in which CMV infection may play a role. This case demonstrates that CMV retinitis is not excluded by negative CMV serology or cultures.

Bilateral cytomegalovirus panuveitis after high-dose corticosteroid therapy

A 30-year-old previously healthy woman who recieved immunosuppressive doses of corticosteroids developed an unusual culture-proved cytomegalovirus panuveitis bilaterally. The atypical clinical course was marked by bilateral exudative detachements with minimal evidence of retinitis. Any patient receiving blood transfusions and immunosuppressive doses of corticosteroids is potentially at risk for developing ocular cytomegalovirus infection, and the clinical presentation of the ocular infection may be atypical.

Rhegmatogenous retinal detachment complicating cytomegalovirus retinitis

Six eyes in four patients with cytomegalovirus retinitis developed retinal holes and retinal detachment. Holes appeared in areas of necrosis and were typically large and round with shaggy edges. Differentiation from exudative detachment was sometimes difficult because of obscuration of the fundus by vitreous haze. Cryotherapy was successful in closing open breaks without detachment; cryotherapy and exoplant surgery were used effectively to treat the initial detachments. The occurrence of massive periretinal proliferation and late development of new areas of hole formation or retinitis complicated therapy for these detachments.

Retinal aneurysms in adult cytomegalovirus retinitis

We observed aneurysms of the retinal arteries, capillaries, and venules occurring in a patient with cytomegalovirus retinitis. These aneurysms were caused by involvement of the retinal vascular endothelium resulting in focal weaknesses in the vascular walls. The clinical appearance of this retinitis superficially resembled retinal branch vein occlusion.

Stimulation of human lymphocytes by cytomegalovirions and dense bodies

Lymphocytes from healthy adult individuals were examined for their ability to incorporate thymidine in the presence of cytomegalovirus (CMV) and dense bodies. It was found that lymphocytes from donors with antibodies to CMV were stimulated to incorporate thymidine-14C both by preparation of CMV and CMV dense bodies. Lymphocytes from CMV seronegative donors did not respond. Dilution experiments and the dose-response curve indicate that the stimulation induced by the dense body preparation was not caused by the small amounts of contaminating CMV particles. These results indicate that in healthy human adults there is a correlation between CMV seropositivity and in vitro lymphocyte transformation, induced by either CMV or by dense bodies.

Bilateral acute retinal necrosis

In this paper 4 patients are described who had bilateral symmetrical confluent retinal swelling followed by apparent necrosis and sloughing of the retina into the vitreous. The disease was accompanied by signs of uveitis and the clinical appearance suggested inflammation rather than infarction as the pathogenic mechanism. No systemic abnormalities were found by which the aetiology could be identified.

Cytomegalovirus retinitis secondary to chronic viremia in phagocytic leukocytes

We studied the relationship between the duration and intensity of cytomegalovirus viremia, cytomegalovirus complement fixing antibody, and cytomegalovirus retinitis in 61 renal transplant recipients. Five (8%) patients had chronic viremia which lasted more than six months. Two of the five developed typical cytomegalovirus retinitis and a severe fungal infection after intensive viremia of more than 11 months' duration. Retinitis did not develop in 22 patients with short-term viremia. Infectious cytomegalovirus was largely associated with polymorphonuclear leukocytes, but the virus was associated with monocytes during the immature granulocytic response accompanying one patient's terminal illness.

Slow virus infections

Slow viruses produce diseases whose incubation periods range from several months to many years. Because of this long latency period, the lack of inflammation produced by these diseases and the lack of recoverable virus particles, it is only recently that the association has been made between the viruses and the diseases they cause. The detailed study of kuru, a neurologic affliction of a remote tribe of cannibals in New Guinea, was responsible for the synthesis of new and previously gathered information into a unified framework to explain not only kuru but other diseases as well. Since then, animal models, transmission experiments and histologic and biochemical studies have unveiled new links connecting viruses to previously obscure neurologic, neurophthalmic and ophthalmic entities.