The Stalagmite Sign: A Novel OCT-IR Biomarker for Peripheral Infectious Retinitis

Area of Science:

• Ophthalmology
• Medical Imaging
• Infectious Diseases

Background:

• Posterior uveitis can present with diverse retinal manifestations.
• Accurate diagnosis of infectious peripheral retinitis is crucial for appropriate management.
• Novel imaging biomarkers are needed to improve diagnostic accuracy.

Purpose of the Study:

• To define the Stalagmite Sign, a multimodal OCT-IR imaging pattern.
• To evaluate the Stalagmite Sign as a diagnostic biomarker for infectious peripheral retinitis in posterior uveitis.
• To assess the diagnostic accuracy of the Stalagmite Sign.

Main Methods:

• Multicenter retrospective case series with diagnostic accuracy analysis.
• Inclusion of 46 eyes with the Stalagmite Sign and 360 sign-negative comparator eyes.
• Calculation of sensitivity, specificity, positive predictive value, and likelihood ratio; assessment of PCR positivity and visual outcomes.

Main Results:

• The Stalagmite Sign was present in 46 eyes, with 95.7% confirmed infectious etiology (toxoplasmosis, herpetic retinitis, syphilis, fungal endophthalmitis).
• High specificity (99.1%) and positive predictive value (95.7%) for infectious peripheral retinitis were observed.
• Intraocular PCR was positive in all tested eyes, and visual acuity improved with antimicrobial therapy.

Conclusions:

• The Stalagmite Sign is a highly specific OCT-IR biomarker for infectious peripheral retinitis.
• Recognition of the Stalagmite Sign should prompt peripheral retinal evaluation, PCR, and antimicrobial therapy.
• Avoid corticosteroid monotherapy; PCR is recommended in uncertain cases.