Bacillary layer detachment as an inflammatory biomarker in toxoplasmosis retinochoroiditis: serial evolution on optical coherence tomography.

We describe the clinical course and serial evolution of bacillary layer detachment (BALAD) on optical coherence tomography (OCT) in toxoplasmosis retinochoroiditis and its importance as an inflammatory biomarker. Colour fundus photography and swept-source OCT of the BALAD were done at the time of presentation and subsequently at 1 week, 2 weeks, 4 weeks and at 11 weeks. Treatment involved oral trimethoprim (160 mg) + sulphamethoxazole (800 mg) two times per day, started at presentation for 2 months. Oral prednisolone was started after 1 week at a dose of 50 mg a day and tapered weekly over the next 5 weeks. The BALAD initially increased after starting treatment with trimethoprim-sulphamethoxazole and regressed within 1 week after initiation of oral prednisolone. Best corrected visual acuity improved to 20/40 from 20/160 at presentation (Snellen equivalent). This suggests that BALAD is an indicator of an acute inflammatory event and the accumulated fluid is secondary to retinal and choroidal inflammation.

A new perspective in the treatment follow-up of toxoplasma retinochoroiditis: Infiltrate thickness measurement.

BACKGROUND: This study aimed to describe the spectral domain optical coherence tomography (SD-OCT) findings of active lesions in toxoplasma retinochoroiditis cases and to examine the changes in retinochoroidal infiltrate thickness after treatment. METHODS: A total of 21 newly diagnosed patients with ocular toxoplasmosis were included in this prospective study. A complete ophthalmologic examination and SD-OCT were performed at the first visit. The patients were followed up weekly, and the SD-OCT images were taken over the lesion at each visit for 6 weeks. The characteristics of the active retinochoroiditis focus at the first visit were determined, and the infiltrate thicknesses at all visits were analyzed. RESULTS: A statistically significant BCVA difference was observed at the first visit and at the last visit 6 weeks later (p < 0.01). The first week after treatment showed a significant decrease in infiltrate thickness (113.904 ± 86.001 µm). In the following weeks, this decrease continued more softly. The thickness change at 6 weeks was significantly reduced (16.095 ± 14.784 µm) compared with the previous ones. Weekly infitrate thickness changes were compared among themselves; a statistically significant difference was found between the 1st and 2nd weeks and the 5th and 6th weeks (p = 0.035 and p = 0.007, respectively). Detached posterior vitreous in 71% (15/21) and increased posterior vitreous thickness in 76% (16/21) of active lesion were detected. All patients had 100% (21/21) increased retinal reflectivity and disorganized retinal layers, and choroidal hypo-reflectivity was observed in 86% (18/21). CONCLUSION: SD-OCT is a useful imaging modality in the diagnosis and follow-up of ocular toxoplasmosis cases. Serial thickness measurements of toxoplasma retinochoroiditis lesions may help confirm our diagnosis and determine the need for treatment.

NEW OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FINDINGS ON AN INTRARETINAL VASCULAR PROCESS SECONDARY TO TOXOPLASMA RETINOCHOROIDITIS: 2 CASE REPORTS.

BACKGROUND/PURPOSE: To determine which retinal layer is primarily involved in intraretinal vascular processes associated with Toxoplasma retinochoroiditis using multimodal imaging, including optical coherence tomography angiography (OCTA). METHODS: Toxoplasma retinal lesions were analyzed through multimodal imaging, including color fundus photographs, fluorescein angiography, indocyanine green angiography, spectral-domain OCT, and OCTA. RESULTS: Two patients with atypical features of Toxoplasma retinochoroiditis are described in the acute phase. The first patient presented with a primary episode of acute Toxoplasma retinitis associated with an intraretinal abnormal vascular process that was detected at the acute phase by indocyanine green angiography and was better delineated by OCTA. Seven months later, the intraretinal vascular process had fully resolved on OCTA imaging. The second patient presented with a recurrence of active Toxoplasma retinochoroiditis adjacent to a pre-existing pigmented scar. He had a similar abnormal intraretinal vascular process that was identified on both fluorescein angiography at the early phase and indocyanine green angiography, which was also confirmed by OCTA imaging. CONCLUSION: We report a new finding associated with Toxoplasma chorioretinitis: an abnormal intraretinal vascular process that resolved without anti-vascular endothelial growth factor therapy but after toxoplasmosis treatment alone.

Automatic Diagnosis of Ocular Toxoplasmosis from Fundus Images with Residual Neural Networks.

Ocular toxoplasmosis (OT) is commonly diagnosed through the analysis of fundus images of the eye by a specialist. Despite Deep Learning being widely used to process and recognize pathologies in medical images, the diagnosis of ocular toxoplasmosis(OT) has not yet received much attention. A predictive computational model is a valuable time-saving option if used as a support tool for the diagnosis of OT. It could also help diagnose atypical cases, being particularly useful for ophthalmologists who have less experience. In this work, we propose the use of a deep learning model to perform automatic diagnosis of ocular toxoplasmosis from images of the eye fundus. A pretrained residual neural network is fine-tuned on a dataset of samples collected at the medical center of Hospital de Clínicas in Asunción, Paraguay. With sensitivity and specificity rates equal to 94% and 93%,respectively, the results show that the proposed model is highly promising. In order to replicate the results and advance further in this area of research, an open data set of images of the eye fundus labeled by ophthalmologists is made available.

Clinical and Multimodal Imaging Findings and Risk Factors for Ocular Involvement in a Presumed Waterborne Toxoplasmosis Outbreak, Brazil1.

In 2015, an outbreak of presumed waterborne toxoplasmosis occurred in Gouveia, Brazil. We conducted a 3-year prospective study on a cohort of 52 patients from this outbreak, collected clinical and multimodal imaging findings, and determined risk factors for ocular involvement. At baseline examination, 12 (23%) patients had retinochoroiditis; 4 patients had bilateral and 2 had macular lesions. Multimodal imaging revealed 2 distinct retinochoroiditis patterns: necrotizing focal retinochoroiditis and punctate retinochoroiditis. Older age, worse visual acuity, self-reported recent reduction of visual acuity, and presence of floaters were associated with retinochoroiditis. Among patients, persons >40 years of age had 5 times the risk for ocular involvement. Five patients had recurrences during follow-up, a rate of 22% per person-year. Recurrences were associated with binocular involvement. Two patients had late ocular involvement that occurred >34 months after initial diagnosis. Patients with acquired toxoplasmosis should have long-term ophthalmic follow-up, regardless of initial ocular involvement.

Multimodal Imaging in Ocular Toxoplasmosis.

Multimodal imaging relies on combination of multiple imaging modalities to precisely delineate pathological changes in the posterior segment of the eye associated with a wide range of conditions. This combined application of fundus photography, optical coherence tomography, fundus reflectance/autofluorescence and fundus angiography (with fluorescein, indocyanine green and/or optical coherence tomography) is of great utility for assessment of patients with ocular toxoplasmosis. Multimodal imaging is helpful to characterize the typical pattern of toxoplasmic retinochoroiditis, with primary focal inflammatory involvement of the neurosensory retina, and secondary changes at the level of underlying choroid, retinal blood vessels, vitreous and even optic disc. It may also be valuable to document and follow local complications, including macular edema, vascular occlusions, and choroidal neovascularization, among others.

Visual Outcomes in Presumed Congenital Foveal Toxoplasmosis.

PURPOSE: Congenital macular lesions attributed to toxoplasmosis may limit potential visual acuity. The appearance and location of these scars may cause physicians to overlook associated amblyopia. This study reviews the visual outcomes and benefits of amblyopia therapy in children with foveal toxoplasmosis scars. DESIGN: Retrospective observational case series. METHODS: Setting: Single center. PATIENT POPULATION: Children with presumed foveal toxoplasmosis scars who underwent amblyopia treatment. MAIN OUTCOME MEASURE: Charts were reviewed for amblyopia treatment, fundus photographs, optical coherence tomography (OCT), and visual acuity. RESULTS: Median age at presentation was 2.8 years and median follow-up was 6.2 years. Occlusion therapy was undertaken in 9 patients. Median duration of occlusion therapy was 1.7 years. Six patients improved with occlusion therapy (average 4.6 lines gained on optotype acuity). Final visual acuity ranged from 20/25 to 20/250, with 6 of 8 patients better than 20/80. OCT confirmed macular scars in 5 patients, with varying degrees of foveal architecture disruption. CONCLUSION: Despite the striking appearance of the lesions in patients with presumed foveal toxoplasmosis, visual potential may be better than expected. The appearance of the lesions is not always predictive of visual outcome. A trial of occlusion therapy to treat amblyopia should be initiated in these patients to ensure that they reach their maximal visual potential.

Novedades para el diagnóstico de la toxoplasmosis ocular: uso de la tomografía de coherencia óptica / Advances in the diagnosis of ocular toxoplasmosis: Use of optical coherence tomography

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Model Systems for Studying Mechanisms of Ocular Toxoplasmosis.

The most common human disease caused by infection with Toxoplasma gondii is ocular toxoplasmosis, which typically is manifest as recurrent attacks of necrotizing retinal inflammation with subsequent scarring. The multilayered retina contains specialized cell populations, including endothelial cells, epithelial cells, neurons and supporting cells, all of which may be involved in this condition. In vitro investigations of basic mechanisms operating in human ocular toxoplasmosis use cellular and molecular methods that are common to the study of many pathological processes, and the novel aspect of this research is the use of human retinal cell subsets. Most in vivo research on ocular toxoplasmosis is conducted in the laboratory mouse. Experimental models involve local or systemic inoculation of parasites to induce acute disease, or sequential systemic and local parasite inoculations to trigger recurrent disease. We present methods for in vitro and in vivo studies of ocular toxoplasmosis, including dissection of the human eye, and culture and infection of differentiated cell populations from the retina, as well as induction of mouse ocular toxoplasmosis by intraocular, or sequential systemic and intraocular, inoculations, and imaging of toxoplasmic retinal lesions.

Clindamicina intravítrea como alternativa terapéutica en la toxoplasmosis ocular severa / Intravitreal clindamycin as a therapeutic alternative in severe ocular toxoplasmosis

La toxoplasmosis ocular es una enfermedad que puede tener graves consecuencias visuales. El objetivo es presentar un caso clínico de toxoplasmosis ocular bilateral severa en una paciente alérgica a sulfamidas en el que la reactivación monolateral de la enfermedad responde de forma favorable ante el tratamiento con clindamicina intravítrea y corticoterapia oral. Se muestra como la administración de clindamicina mediante inyecciones intravítreas semanales supone una alternativa terapéutica segura en aquellos casos de toxoplasmosis ocular severa y/o en los que existe contraindicación para el tratamiento clásico. La clindamicina intravítrea es una alternativa terapéutica segura con resultados clínicos favorables

Ocular toxoplasmosis is a disease than have severe consequences on the eyesight. The aim of this study article is to present a bilateral ocular toxoplasmosis in a sulfamide allergic patient with unilateral activation and her favourable progression with intravitreal Clindamycin and oral steroids treatment. Weekly intravitreal Clindamycin treatment is shown to be a suitable therapeutic alternative in cases of severe ocular toxoplasmosis and/or in patients with a contraindication to classical treatment. Intravitreal Clindamycin treatment is a safe alternative with favourable clinical results

Intravitreal clindamycin as a therapeutic alternative in severe ocular toxoplasmosis. / Clindamicina intravítrea como alternativa terapéutica en la toxoplasmosis ocular severa.

Ocular toxoplasmosis is a disease than have severe consequences on the eyesight. The aim of this study article is to present a bilateral ocular toxoplasmosis in a sulfamide allergic patient with unilateral activation and her favourable progression with intravitreal Clindamycin and oral steroids treatment. Weekly intravitreal Clindamycin treatment is shown to be a suitable therapeutic alternative in cases of severe ocular toxoplasmosis and/or in patients with a contraindication to classical treatment. Intravitreal Clindamycin treatment is a safe alternative with favourable clinical results.

Morphological characteristics of ocular toxoplasmosis and its regression pattern on swept-source optical coherence tomography angiography: a case report.

BACKGROUND: To report the successful treatment of ocular toxoplasmosis and present the use of multimodal imaging to describe the changes in ocular toxoplasmic lesions subsequent to treatment. CASE PRESENTATION: A 73-year-old female visited the clinic with decreased visual acuity in the left eye. Fundus examination showed severe vitreous haze with yellow-white infiltrates near the foveal center. Spectral-domain optical coherence tomography (SD-OCT) revealed disorganization of the retinal structure with markedly thickened choroid beneath the active lesion. Highly elevated serum titers of IgG antibodies against Toxoplasma gondii were observed. Topical and systemic steroids with oral Bactrim were administered after a diagnosis of ocular toxoplasmosis was made. After improvement in the severity of vitritis, structural en face swept-source optical coherence tomography (SS-OCT) imaging demonstrated diffuse choroidal dilation with many collateral vascular branches surrounding the active lesion. Eight intravitreal injections of clindamycin (1 mg/0.1 ml) were administered at 1- to 2-week intervals along with systemic antibiotics and steroids. After the treatment, the toxoplasmic lesion resolved to an atrophic chorioretinal scar. Dilated choroidal vessel size was normalized and collateral vascular branches were markedly constricted on structural en face SS-OCT images. CONCLUSIONS: This is the first detailed report on the morphological changes in the choroidal vasculature surrounding ocular toxoplasmic lesions that were characterized using SS-OCT-A imaging. Multimodal imaging with SS-OCT-A can be valuable in clinical diagnosis as well as in clarifying the mechanism of choroidal structural changes in ocular toxoplasmosis.

Ultrasonographic characteristics of active ocular toxoplasmosis / Achados ultrassonográficos em toxoplasmose ocular ativa

ABSTRACT Purpose: To evaluate ophthalmic ultrasonographic findings associated with active ocular toxoplasmosis. Methods: Forty-seven eyes with active ocular toxoplasmosis in 47 patients were subjected to ocular ultrasonography using the transpalpebral technique (10-MHz transducer) and fundus photography. Patient medical records were retrospectively reviewed. Results: Ocular ultrasonography revealed vitritis, posterior vitreous detachment, retinal wall thickening, and non-rhegmatogenous retinal detachment in 47 (100%), 36 [76.6%; partial in 12 (25.5%) and total in 23 (48.9%)], 12 (25.5%), and 5 eyes (10.6%). Thirty-five of the 36 eyes with posterior vitreous detachment (97.2%) exhibited posterior hyaloid thickening; moreover, adhesion to the exudative lesion and vitreoschisis were observed in 4 (11.1%) and 12 eyes (25.5%), respectively. Ultrasonography detected the location of the exudative focus in 12 eyes (25.5%). Conclusion: Ultrasonography is helpful for detecting important intraocular findings of acute ocular toxoplasmosis that can be hindered by medial opacity or posterior synechiae.

RESUMO Objetivo: Avaliar os achados da ultrassonografia na toxoplasmose ocular ativa. Métodos: Quarenta e sete olhos com toxoplasmose ocular ativa em 47 pacientes foram submetidos à ultrassonografia ocular pela técnica transpalpebral (transdutor de 10 MHz) e fundo de olho. Os prontuários médicos foram revistos retrospectivamente. Resultados: A ultrassonografia ocular revelou vitreíte, descolamento vítreo posterior, espessamento da parede da retina e descolamento de retina não regmatogênico em 47 (100%), 36 [76,6%; parcial em 12 (25,5%) e total em 23 (48,9%)], 12 (25,5%) e 5 olhos (10,6%). Trinta e cinco dos 36 olhos com descolamento vítreo posterior (97,2%) exibiram espessamento hialoide posterior; além disso, a adesão à lesão exsudativa e vitreosquise foi observada em 4 (11,1%) e 12 (25,5%), respectivamente. A ultrassonografia detectou a localização do foco exsudativo em 12 olhos (25,5%). Conclusão: A ultrassonografia é útil na detecção de importantes achados intra-oculares de toxoplasmose ocular aguda que podem ser prejudicados pela opacidade medial ou sinéquia posterior.

Ultrasonographic characteristics of active ocular toxoplasmosis.

PURPOSE: To evaluate ophthalmic ultrasonographic findings associated with active ocular toxoplasmosis. METHODS: Forty-seven eyes with active ocular toxoplasmosis in 47 patients were subjected to ocular ultrasonography using the transpalpebral technique (10-MHz transducer) and fundus photography. Patient medical records were retrospectively reviewed. RESULTS: Ocular ultrasonography revealed vitritis, posterior vitreous detachment, retinal wall thickening, and non-rhegmatogenous retinal detachment in 47 (100%), 36 [76.6%; partial in 12 (25.5%) and total in 23 (48.9%)], 12 (25.5%), and 5 eyes (10.6%). Thirty-five of the 36 eyes with posterior vitreous detachment (97.2%) exhibited posterior hyaloid thickening; moreover, adhesion to the exudative lesion and vitreoschisis were observed in 4 (11.1%) and 12 eyes (25.5%), respectively. Ultrasonography detected the location of the exudative focus in 12 eyes (25.5%). CONCLUSION: Ultrasonography is helpful for detecting important intraocular findings of acute ocular toxoplasmosis that can be hindered by medial opacity or posterior synechiae.

Macular Colobomata: Comparison of Clinical and Optical Coherence Tomography Features With Serologic Results.

PURPOSE: To assess the correlation between the morphologic features and serology in eyes with macular colobomata (MC). DESIGN: Retrospective comparative case series. METHODS: Setting: Institutional. STUDY POPULATION: Patients presenting with MC to the retina clinic over a period of 2 years (January 2016 to December 2017). Interventional/Observational Procedure: Color fundus and swept-source optical coherence tomography (SSOCT) features were reviewed and assessed in 3 groups based on the serum IgG results: positive for Toxoplasma, positive for cytomegalovirus (CMV), and serology negative. MAIN OUTCOME MEASURE: Morphologic features on clinical and OCT-based examination. RESULTS: A total of 49 eyes of 27 patients were recruited. The mean age was 24.8 ± 14.9 years (range 7-60 years). While the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae (large choroidal vessels) on SSOCT differed significantly among the groups, pigmentation, retinal fibrosis, shape, retinal vessel pattern, and choroidal vessel visibility did not vary significantly. The lesions in CMV serology-positive cases were mostly solitary (n = 8/8), large (n = 5/8) and deeply excavated (n = 8/8). The lesions in Toxoplasma serology-positive cases were mostly flat to shallow (n = 18/26), medium-sized (n = 19/26), and either a solitary lesion (n = 17/26) or multiple satellite lesions (n = 9/26). The lesions in serology-negative cases were mostly small to medium (n = 13/15), solitary (n = 15/15), deeply excavated lesions (n = 11/15) with choroidal lacunae (n = 8/15). CONCLUSIONS: The clinical and SSOCT features such as the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae can provide a clue toward the etiology of macular colobomata.

Swept-source optical coherence tomography and optical coherence tomography angiography in acquired toxoplasmic chorioretinitis: a case report.

PURPOSE: To describe swept-source optical coherence tomography and optical coherence tomography angiography retinal changes in a case of acute toxoplasmic chorioretinitis both at the time of diagnosis and after healing. CASE PRESENTATION: A 57-year-old white woman suffering from acquired toxoplasmic chorioretinitis underwent swept-source optical coherence tomography and optical coherence tomography angiography both at the time of diagnosis and after healing. In the acute phase of the disease, swept-source optical coherence tomography clearly showed retinal and choroidal involvement in the superficial retina and in the choroidal swelling. Optical coherence tomography angiography showed a complete loss of deep and superficial capillary networks and of choroidal vessels in the area of the inflammation. After healing, swept-source optical coherence tomography showed a retinal thinning of the area involved, with a subversion of retinal layers and no visible change at the choroid level. On the other hand, optical coherence tomography angiography showed the persistence of a vascular occlusion at the retina and choroid level. CONCLUSION: This is the first case in the optical coherence tomography angiography literature that shows the imaging of toxoplasmic chorioretinal lesions. This case confirms the involvement of the retina and choroid in toxoplasmic uveitis and the disruptive potential of such inflammation. The optical coherence tomography angiography performed after healing showed a persistent ablation of the retina, choriocapillaris, and choroidal vessels. The non-invasive optical coherence tomography angiography imaging technique may have diagnostic and prognostic value in regard to toxoplasmic uveitis.

Causes of visual impairment in patients with ocular toxoplasmosis.

INTRODUCTION: The aim of this study was to report the causes of visual impairment in patients with the classic clinical presentation of ocular toxoplasmosis (OT). METHODOLOGY: Eight patients with OT underwent standardized ophthalmologic examination and fundus imaging. Macula and the lesions that could be visualized were evaluated by spectral domain optical coherence tomography (SOCT) at presentation. The scan acquisition protocols for SOCT included a radial line scan through the retinochoroiditis lesion, radial line macular scan, and horizontal volume scans at the macula. RESULTS: The mean age of the five (62.5%) women and three (37.5%) men was 25.7±7.6 years. The mean logMAR ETDRS best-corrected visual acuity was 0.45 (Snellen equivalent, 20/50). SOCT findings of macula were normal in seven patients, and one patient had decreased retinal thickness from a healed chorioretinitis at the fovea. Of eight patients, two had 3+ vitreous haze, four had 2+ vitreous haze, and two had 1+ vitreous haze at presentation. OCT scans revealed vitreous hyperreflective dots in all patients with different densities in different radial scans. Hyperreflective dots were denser in macular scans of eyes in which the active lesion was closer to the fovea. CONCLUSIONS: In this study, visual impairment in majority of the patients was found to be related to vitreous cells and flare. Dense vitritis on macula scans and visual impairment were seen in the patients who had an active lesion closer to the fovea. SOCT may provide objective data of the cellular load of the eyes with posterior segment inflammation.