Fundus autofluorescence detects subtle pigmentary alterations in pigmented paravenous retinochoroidal atrophy.

Case report

A 48-year-old Asian female with no significant past medical history was referred for blurry vision in the right eye. On examination, visual acuity was 20/40 in the right eye and 20/20 in the left eye. Intraocular pressure was 14 mmHg in both eyes. Anterior segment examination was unremarkable. Posterior segment examination demonstrated significant pigment accumulation along the distribution of retinal veins in the right eye, whereas the left eye demonstrated subtle paravenous pigmentary changes without significant pigment clumping (Fig. 1A and B). On green wavelength fundus autofluorescence (FAF, Optos; Marlborough, MA), hypoautofluorescent lesions corresponded to pigmentary accumulation and were much more marked in the right eye. Hyperautofluorescent lesions corresponded to subtle pigmentary alterations, often difficult to detect ophthalmoscopically (Fig. 1C and D). A peripheral blood sample was sent to Invitae (San Francisco, CA), where 248 genes implicated in inherited retinal dystrophies were tested and found to be negative for any variants that could be causative for the patient's phenotype. The patient had no known history of trauma. Of note, exam and fluorescein angiography showed no signs of an inflammatory process. A diagnosis of pigmented paravenous retinochoroidal atrophy (PPRCA) was made.

Fig. 1

Pigmented Paravenous Retinochoroidal Atrophy (PPRCA). Color fundus photography of the right (A) and left (B) eye, and green wavelength fundus autofluorescence (FAF) of the right (C) and left (D) eye highlighting the utility of FAF in detecting subtle pigmentary alterations in this condition.

Discussion

PPRCA is a relatively uncommon, typically bilateral and symmetric, slowly progressive disorder characterized by retinal pigment epithelium (RPE) and choriocapillaris atrophy with pigment deposits along retinal veins. Although PPRCA typically carries a good visual prognosis, it is associated with a gradual loss of peripheral retinal function. FAF typically demonstrates paravenous areas of hypo- and hyperautofluorescence consistent with RPE loss or dysfunction, respectively. Because masquerades have been reported in association with inflammatory conditions such as Vogt-Koyonagi-Harada syndrome, a thorough search for uveitic stigmata by exam and fluorescein angiography should be carried out prior to diagnosis. We present a case of asymmetric PPRCA with minimal fundus abnormality in one eye, difficult to observe on exam, to highlight the utility of FAF in this condition.

Conclusion

Green wavelength FAF can detect subtle pigmentary abnormalities in PPRCA otherwise difficult to observe, assisting the clinician in making the diagnosis prior to the onset of RPE loss and pigment accumulation.

Funding

No funding or grant support.

Authorship

All authors attest that they meet the current ICMJE criteria for Authorship. Consent to publish this case report was not obtained. This report does not contain any personal information that could lead to the identification of the patient.

Declaration of competing interest

The following authors have no financial disclosures: SG, DS.