Julie Rodman

In vivo diagnostic imaging of ocular toxocariasis.

Toxocariasis was first reported in the early 1950s. Distribution is worldwide but the incidence is highest in the southeastern United States, Puerto Rico and the West Indies. Serological surveys have indicated that from four to 30 per cent of people in the United States are infected with the parasite. Two clinical diseases are described: visceral larva migrans (VLM) affecting multiple systemic organs and ocular larva migrans (OLM) affecting the eye. Ocular involvement appears clinically as a granuloma of the posterior pole or peripheral retina, or as an endophthalmitis. Ocular toxocariasis carries a poor visual prognosis secondary to its widespread tissue involvement. Accurate diagnosis of the active condition, timely intervention (when needed) and awareness of important sequelae are crucial. Posterior segment imaging technologies such as optical coherence tomography (OCT) and B-scan ultrasonography may aid in diagnosis and management, as well as increase our understanding of the pathophysiology of this condition.

Serpiginous choroiditis in a herpes-positive patient.

Background. Viruses are one of the most common causes of infections involving the posterior segment of the eye. Viral infections can be congenital or acquired and can affect the retina, choroid, or optic nerve. Herpes simplex virus has been implicated in a number of posterior segment conditions, including serpiginous choroiditis (SC), which has generally been described as idiopathic. Case Report. A 57-year-old black female presented with decreased and distorted vision in both eyes, of 10 months duration. Funduscopy revealed radial, deep grayish lesions emanating off of the optic disc in a peripapillary fashion. The clinical appearance was suggestive of SC, which was confirmed by fluorescein angiography. Serologic testing was positive for herpes simplex virus and thus may suggest a causative link between the virus and the choroiditis. Conclusions. SC has been historically cited as an idiopathic process. There have been only rare reports linking this process with a viral etiology. Laboratory testing and clinical work-up needs to be obtained in any patient suspected of having SC, to detect a viral etiology. Treatment of an underlying condition may lead to optimum resolution in these patients.

Cystoid Macular Edema as a Result of Immune-recovery Uveitis

Background. Potent antiretroviral therapy can lead to improved immunity in patients with acquired immune deficiency syndrome. However, ocular inflammation can occur in predisposed individuals. This inflammation is referred to as immune-recovery uveitis. Cystoid macular edema (CME) is a complication that can result from this inflammation and is emerging as a major cause of visual loss in human immunodeficiency virus (HIV)-infected patients. Case Report. A 52-year-old man presented with complaints of intermittent decreased vision that had coincided with the initiation of antiviral treatment. He also reported metamorphopsia and floaters in both eyes of several years duration. He had a history of HIV for 20 years and was only recently started on Highly Active Antiretroviral Therapy (HAART). He reported a vague history of ocular problems involving his retina. Retinal examination revealed bilateral areas of peripheral scarring from presumed past ocular inflammation and thickening and irregularity at each macula. Ancillary testing was performed, and CME was diagnosed. Conclusions. Immune-recovery uveitis is a leading cause of visual disturbance in HIV-infected patients with a history of cytomegalovirus (CMV) retinitis on HAART. Although the immune recovery associated with the advent of HAART has decreased the need for potent CMV medications, the heightened immune response can be associated with sight-threatening inflammation.

Acute macular neuroretinopathy: the evolution of the disease through the use of newer diagnostic modalities

Acute macular neuroretinopathy (AMNR) is a rare condition that occurs most often in healthy, young women. Acute macular neuroretinopathy may present as an asymptomatic condition but is typically associated with transient, variable visual disturbances, such as scotomata, metamorphopsia and mild decrease in vision. Symptoms differ in frequency and persistence. The condition was first described in 1975 by Bos and Deutman, who believed that the distinct retinal lesions seen in acute macular neuroretinopathy involve the inner retina and the superficial retinal layers. Ophthalmoscopically, these patients present with lobular, reddish brown, wedge-shaped lesions in the parafoveal area. Resolution of the lesions is common; however, the lesions may persist years later. The pathophysiology is uncertain and there is no proven treatment for the condition.

Juxtapapillary choroidal neovascular membrane following optic neuritis

Choroidal neovascularisation is defined as the formation of new blood vessels originating from the choriocapillaris that grow and break through Bruch’s membrane, creating a neovascular network. This neovascular network has the potential not only to expand within the choroid but also to invade under the retinal pigment epithelium (RPE). Choroidal neovascular membranes (CNVM) have the potential to expand into the neurosensory retina and even break through the posterior hyaloid face proliferating into the vitreous cavity. A compromise in the interface between the RPE and Bruch’s membrane allows for the development of a choroidal neovascular membrane. CNVMs can be categorised as Type I or Type II, depending on the location of the network of vessels. In Type I CNVM, the new blood vessels grow under the RPE and in Type II, the network grows under the neurosensory retina. CNVM can be further classified as subfoveal, juxtafoveal, extrafoveal or juxtapapillary. To make the appropriate diagnosis, specific ancillary testing must be used. Fluorescein angiography, indocyanine green angiography and optical coherence tomography aid in both characterising and localising a CNVM. Juxtapapillary choroidal neovascularisation is an uncommon entity that has been associated with numerous conditions including pseudotumour cerebri, optic disc drusen, optic disc oedema, congenital disc anomalies, peripapillary choroidal melanoma, peripapillary choroidal naevus, choroidal osteoma, degenerative myopia, angioid streaks, histoplasmosis, sarcoidosis and other inflammatory conditions. These optic nerve head lesions are usually associated with juxtapapillary anomalies of the choroid, RPE or Bruch’s membrane that provide the setting for choroidal neovascularisation to occur. This case illustrates the development of a juxtapapillary choroidal neovascular membrane in a patient with a history of optic neuritis.

Outer Retinal Tubulation: A Case Series

PURPOSE The advent of spectral domain optical coherence tomography has led to superb imaging capabilities in addition to enhanced visualization of the retinal layers. Such advancements have led to the identification of a variety of new retinal conditions, including outer retinal tubulations (ORTs). ORTs are ovoid hyporeflective spaces located in the outer retina. The pathogenesis is unclear but seems to involve sublethal injury to the photoreceptors leading to a compensatory reorganization of the photoreceptor layer with the neighboring ellipsoid zone resulting in a hyperreflective border surrounding a central lumen. Most ORTs have been linked to wet age-related macular degeneration; however, these peculiar structures are now seen in a myriad of retinal disorders. CASE REPORTS Our cases will highlight the wide variety of clinical presentations associated with outer retinal tubulations. The clinical presentations include two cases of wet age-related macular degeneration, a case of presumed ocular histoplasmosis syndrome, a case of central areolar choroidal dystrophy, and a case of pathological myopia. CONCLUSIONS By correctly differentiating outer retinal tubulations from other masqueraders, unnecessary referrals and interventions can be minimized. Understanding the various disease entities associated with outer retinal tubulation could give further insight into the mechanism and formation of these structures.

More sensitive correlation of afferent pupillary defect with ganglion cell complex

Purpose This study investigated the correlation between the relative afferent pupillary defect (RAPD) and retinal nerve fiber layer thickness (RNFLT) in optic neuropathy. Methods RAPD assessment was performed using a log unit neutral density filter bar. Spectral domain optical coherence tomography RTVue-100 (Optovue) was used to examine the subjects. The optic nerve head pattern (ONH) was subdivided and identified for the purpose of the study into circumpapillary RNFLT (cpRNFLT) and peripheral circumpapillary RNFLT (pcpRNFLT). The cpRNFLT, pcpRNFLT and ganglion cell complex (GCC) parameters were analyzed. Results Eighteen females and twenty three males with asymmetric optic neuropathy and a RAPD participated. Thirty-three subjects had glaucoma and eight had optic neuropathy other than glaucoma. Significant correlations (p < 0.02) were obtained for the RAPD and the percentage difference loss of the GCC and RNFLT parameters. The grouped mean percentage difference loss for RNFLT was significantly different from that of the GCC (p < 0.001). At a 0.6 log unit RAPD, the average mean percentage difference loss was 23% for the CRNFLT, 15% for the GCC, 12% for the global loss volume percentage and 6% for the focal loss volume percentage (FLV%). Conclusions Significant correlations between RNFLT loss for cpRNFLT, pcpRNFLT and GCC parameters with RAPD were observed. Approximately a 35% higher sensitivity was obtained using GCC compared to CRNFL parameters. The expected change in GCC average for every 0.3 log unit increment was approximately 8.49 μm. The FLV% corresponded more sensitively to a RAPD but appeared to be influenced by disease severity.

Focal loss volume best differentiates eyes with afferent pupillary defect

Purpose: To quantify the specificity and sensitivity of RTVue-100, Optovue parameters at determining the presence of a relative afferent pupillary defect (RAPD) by coupling their values with the instrument normative data base (NDB) and the presence of a RAPD. To generate the distribution for the focal loss volume (FLV) percentage, by coupling its value to the instrument NDB and presence of a RAPD. Methods: Forty one subjects with a RAPD and glaucomatous or non-glaucomatous optic neuropathy participated. A neutral density filter bar was used to estimate the RAPD. The specificity and sensitivity of all parameters was analyzed using Fisher’s Exact test. The distribution of the FLV percentage was analyzed using a one-way ANOVA with a Tukey HSD post hoc test. Results: The FLV percentage was more sensitive (100%) but less specific (64%) than other parameters. Eyes of subjects with FLV percentage and NDB p-values < 1% were 33.8 times more likely to have a RAPD [95% CI: 7.2, 325.1]. Confidence limits for the distribution of FLV percentage were; 6.32/10.59 um for eyes with NDB p-values < 1% with a RAPD; 2.04/7.56 um for eyes with NDB p-values >1% with a RAPD and 1.08/6.22 um for eyes with NDB p-values > 1% without a RAPD. Conclusion: Compared to other RTVue-100, Optovue parameters the FLV percentage is more sensitive at determining eyes with a RAPD and may significantly categorize optic neuropathy according to severity.

Variability in Presentation of Bilateral Vitreomacular Traction.

Purpose Vitreomacular traction (VMT) is a condition characterized by an incomplete posterior vitreous detachment resulting in traction on the macula and possible subsequent decrease in visual acuity and/or other symptomatology. Vitreomacular traction often presents as a unilateral condition, with some cases developing bilaterality with disease progression. The natural course and presentation of VMT vary widely among individuals. There is no extensive literature regarding the prevalence of VMT in the general population; therefore, little is known on the laterality. Case Reports We present eight cases of bilateral VMT encountered in a primary care setting. These cases highlight the variability in presentation, symptomatology, and clinical outcome between and within eyes of patients with bilateral VMT. Conclusions Spectral-domain optical coherence tomography has provided new insight into VMT by allowing better visualization of the vitreoretinal interface. Using spectral-domain optical coherence tomography, eight unique cases of bilateral VMT were confirmed and classified. However, despite the bilaterality noted in each case, the clinical presentation and course of disease varied among patients. Because of the paucity of epidemiological data regarding VMT, the laterality of the condition, risk factors for involvement, and overall prognosis remain unclear.