Spectral-domain optical coherence tomographic findings at each stage of punctate inner choroidopathy

Abstract

Purpose: To describe the natural course of punctate inner choroidopathy (PIC) using spectral-domain optical coherence tomography (SD-OCT).

Design: Prospective observational case series.

Participants: Forty-two consecutive patients (60 eyes) with PIC with at least 3 months of follow-up.

Methods: Serial SD-OCT images were obtained from both eyes of each participant at each visit.

Main outcome measures: The morphologic characteristics of each stage of PIC lesions observed by SD-OCT.

Results: Continued stage progression of PIC lesions was observed in 27 eyes (45%), among which choroidal thickness changes were observed in 8 eyes (30%). Stage I lesion showed a normal appearance or slight irregularities in the outer nuclear layer. Stage II lesion appeared as a focal elevation of the retinal pigment epithelium (RPE) with corresponding disruption of the inner and outer segments of the photoreceptor interface. Stage III lesion broke through the RPE, forming a hump-shaped chorioretinal nodule with moderate reflectivity beneath the outer plexiform layer (OPL), generally with subsequent disruption of Bruch's membrane. Nodules occasionally invaded the inner retina, causing segmental retinal phlebitis in 2 eyes. Stage IV lesion regressed in a retrograde manner with tissue loss from the photoreceptor layer and inner choroid, finally leaving a V-shaped hernia of the OPL and inner retina into the choroid. Stage V lesion gradually eliminated the photoreceptors around the lesion; this process was accompanied by RPE proliferation at multiple levels, which reduced retinal herniation. Parafoveal stage V lesions caused late occult macular atrophy in 4 eyes. Choroidal thickness increased throughout the active phase and reached a peak at stage III; this parameter then significantly decreased at stage IV and gradually reached a minimum that was lower than the initial value at stage I.

Conclusions: Punctate inner choroidopathy is a chorioretinitis rather than an inner choroidopathy. Spectral-domain OCT characterized a 5-stage evolution of PIC lesions: choroidal infiltration, formation of sub-RPE nodules, and then chorioretinal nodules, regression, and retinal herniation.