Multimodal imaging: Focusing on uveitis

(Image Credit: AdobeStock/Alessandro Grandini)

Reviewed by Laura J. Kopplin, MD, PhD

Multifocal imaging is invaluable for evaluating patients with uveitis, and different techniques offer different information at different time points. According to Laura J. Kopplin, MD, PhD, the timing can be very important. “You may order a fluorescein angiogram or fundus autofluorescence for patients with new scotomas, new photopsias, or other new visual symptoms when their clinical examinations have not changed in order to ferret out a previously unknown vasculitis or new area of disease activity,” she told Ophthalmology Times.

Kopplin, an assistant professor in the Department of Ophthalmology and Visual Sciences at the University of Wisconsin–Madison, shared her pearls for evaluating this patient population using different imaging techniques during the 2023 Women in Ophthalmology Summer Symposium in Marco Island, Florida. Kopplin offered 5 rules for clinicians to follow.

See what they see

Patients may present with new photopsias or scotomas without obvious changes in clinical examination. Fundus autofluorescence uses the natural fluorescent property of lipofuscin in the retinal pigment epithelium and is particularly beneficial for visualizing areas of active inflammation that might not be overt on fundus examination.

Patterns of hyperautofluorescence vary with the inflammatory process. Key findings to look for include new hyperautofluorescent lesions in multifocal choroiditis, a trizonal pattern in acute zonal occult outer retinopathy and hyperautofluorescence along the edges of serpiginous choroiditis lesions. In multiple evanescent white dot syndrome, the hyperautofluorescent dots persist past the clinical findings and can aid in diagnosis as examination findings fade.

Birdshot chorioretinopathy may show hyperautofluorescence in active disease and then hypoautofluorescence with the development of atrophy. The status of the autofluorescence provides information about the effects of treatment in patients as hyperautofluorescence resolves or transitions to hypoautofluorescence as disease activity wanes.

Feel the heat (map)

Kopplin pointed out that perivascular thickening seen on the optical coherence tomography (OCT) thickness map can be a marker for active vasculitis. The thickness map can provide a less invasive way compared with fluorescein angiography (FA) to track progress during treatment transitions.

FA is still needed, as the heat map visualizes only a small portion of the retina, but sometimes FA can be performed less often. This is often helpful in the pediatric population, in which frequent FAs can be challenging.

An FA today keeps the uveitis away

Some key takeaways include the following:

• Low threshold for FA in patients with uveitis.
• Vasculitis without obvious clinical findings must still be identified as treatment should be considered especially in the presence of posterior pole involvement.
• Ultrawide field angiography allows for a more complete assessment of the retinal vasculature. FA is helpful to assess nonperfusion.¹

Don’t miss the syph(ilis)

Know the imaging findings for acute syphilitic posterior placoid chorioretinitis. Spectral domain OCT shows disruption of the outer retinal bands and irregular retinal pigment epithelial elevations that can be pyramidal in many cases. Fundus autofluorescence demonstrates hyperautofluorescent placoid lesions in the area of retinal disruption. Kopplin advised being alert and testing for syphilis in this setting. “This is a can’t-miss diagnosis,” she said.

Treatment with intravenous penicillin results in remarkable normalization of the photoreceptor laminations, and visual recovery is often good when treatment is not delayed.

Look deeper

Indocyanine green angiography (ICGA) is still a useful imaging modality for identifying choroidal pathology and aids in the diagnosis of birdshot chorioretinopathy, choroiditis, and posterior placoid uveitides.

ICGA may show findings longer than those visible during the clinical examination in multiple evanescent white dot syndrome. Enhanced depth imaging (EDI)-OCT and swept-source OCT are also useful for assessing the choroid in inflammatory diseases.

Choroidal thickening can occur in acute or recurrent Vogt-Koyanagi-Harada disease and clinicians can monitor the patient’s response to treatment using EDI. EDI-OCT also facilitates noninvasive monitoring of choroidal granulomas and allows differentiating between scleral and choroidal lesions.²

“Multifocal imaging is essential in the initial evaluation of [patients with] uveitis and for monitoring their therapeutic response,” Kopplin said.

Laura J. Kopplin, MD, PhD

E: ljkopplin@wisc.edu

Kopplin is an assistant professor in the Department of Ophthalmology and Visual Sciences at the University of Wisconsin–Madison. She has no financial interest in this subject matter.

References:

1. Thomas AS, Lin P. Multimodal imaging in infectious and noninfectious intermediate, posterior and panuveitis. Curr Opin Ophthalmol. 2021;32(3):169-182. doi:10.1097/ICU.0000000000000762

2. Bolletta E, De Simone L, Pellegrini M, et al. Optical coherence tomography in inflammatory and neoplastic lesions deforming the choroidal profile. Diagnostics (Basel). 2023;13(12):1991. doi:10.3390/diagnostics13121991