Choroidal abnormalities in birdshot chorioretinopathy: An indocyanine green angiography study

Abstract

Birdshot chorioretinopathy is a rare inflammatory disorder with an insidious onset that can slowly progress to severe visual loss. The pathogenesis is unknown. This study used indocyanine green (ICG) angiography to investigate the degree of choroidal vascular involvement with progression of disease and to determine the nature of the birdshot lesions. Seven patients with birdshot chorioretinopathy had ICG angiography performed with a scanning laser ophthalmoscope at various stages of clinical disease. Results were compared with fluorescein fundal angiography (FFA). All large choroidal vessels appeared normal. The birdshot lesions were demonstrated with ICG but not with FFA and were represented by dark areas on ICG angiography. Typically these areas were bordered by large or medium-sized choroidal vessels and their appearance suggested small choroidal vessel hypoperfusion. In disease of recent onset, some lesions masked fluorescence from large underlying choroidal vessels possibly due to inflammatory choroidal infiltrates. In long-standing disease, the choroidal angioarchitecture was relatively normal within the birdshot lesions. This study of birdshot chorioretinopathy demonstrates abnormalities in the small choroidal vessels within the birdshot lesions. ICG angiography detects the birdshot lesions more readily than FFA and may be of benefit in assessing disease activity.

Birdshot chorioretinopathy

“…The ability of fluorescein angiography to detect spots, however, is variable. For this purpose, indocyanine green Monnet et al [20 ] Kiss et al [22] Thorne et al [21 ] Becker et al [23 ] Rothova et al [19] Year angiography could be more sensitive than fluorescein angiography [33]. Furthermore, one report [34] suggests that the variable aspects of spots on indocyanine green angiography could be a marker of disease activity.…”

Choroidal Findings in Eyes With Birdshot Chorioretinitis Using Enhanced-Depth Optical Coherence Tomography

“…[6][7][8]27 Relationships between these changes and the lesions seen on EDI-OCT are not known. Interpretation of ICG angiograms may be challenging, and serial monitoring of patients with BSCR using ICG angiography IQR ¼ interquartile range.…”

Examining the Choroid in Ocular Inflammation: A Focus on Enhanced Depth Imaging

“…These lesions radiate from the disc towards the equator and are frequently associated with mild vitritis. The majority of affected patients have a positive HLA-A29 allele and FFA usually shows venous hyperfluorescence with extensive late intraretinal and disc leakage [9]. …”

“…The choroid has been implicated in the pathogenesis of many posterior segment inflammatory disorders, including Vogt-Koyanagi-Harada syndrome (VKH) [3], Behçet's disease [4, 5], sarcoidosis [6, 7], birdshot chorioretinopathy [8, 9], sympathetic ophthalmia [10, 11], panuveitis [12], toxoplasmosis [13], and posterior scleritis [14]. Due to the location of the choroid under the RPE most clinically available imaging modalities including fundus fluorescein angiogram (FFA), B-Scan ultrasonography, and optical coherence tomography (OCT) provide only partial information regarding its structure and function.…”