Structural Retinal and Choroidal Changes in Toxoplasmic Retinochoroiditis Assessed by Swept-Source Optical Coherence...

Area of Science:

• Ophthalmology
• Medical Imaging
• Infectious Diseases

Background:

• Toxoplasma retinochoroiditis (TRC) presents with varied clinical activity.
• Accurate staging is crucial for effective management and monitoring of TRC.
• Swept-source optical coherence tomography (SS-OCT) offers high-resolution cross-sectional imaging of the retina and choroid.

Purpose of the Study:

• To characterize distinct retinal and choroidal structural changes in active, reactive, and inactive phases of TRC using SS-OCT.
• To establish stage-specific imaging biomarkers for TRC.
• To evaluate the utility of SS-OCT in therapeutic decision-making and disease monitoring.

Main Methods:

• A retrospective study analyzed 33 patients (39 eyes) with TRC, categorized into active, reactive, or inactive phases.
• SS-OCT was employed to measure central foveal thickness (CFT), subfoveal choroidal thickness (SFCT), retinal layers, and vitreous characteristics.
• Statistical analyses included Kruskal-Wallis H test and multivariate logistic regression; interobserver reproducibility was assessed using intraclass correlation coefficients (ICC).

Main Results:

• Active TRC eyes exhibited significant retinal edema (CFT) and choroidal thickening (SFCT), along with vitreous abnormalities and fluid.
• Reactive phases showed intermediate changes with retinal pigment epithelium (RPE) hyperreflectivity and outer retinal atrophy.
• Inactive TRC eyes demonstrated retinal thinning, ellipsoid zone disruption, RPE loss, and epiretinal membranes; CFT and SFCT were significantly different across phases (p<0.01).

Conclusions:

• SS-OCT reveals distinct structural signatures correlating with TRC disease activity phases.
• These findings validate SS-OCT for quantifiable disease staging, treatment monitoring, and prognostication in TRC.
• Further multimodal imaging studies are warranted to complement SS-OCT findings.