The superficial and deep retinal capillary plexus in cases of fovea plana imaged by spectral-domain optical coherence tomography angiography

Abstract

Purpose: To describe the appearance of the superficial and deep retinal capillary plexi in three patients with fovea plana of differing severity using spectral-domain optical coherence tomography angiography (OCTA).

Observations: In the first case of grade 1 fovea plana (a patient with 20/25 vision), OCTA showed an orderly branching pattern of vessels from the superficial and deep retinal plexi extending to the center of the fovea. The second case of grade 3 fovea plana (20/30 vision) showed some disruption of the orderly vascular pattern with small caliber vessels from both superficial and deep layers densely covering the fovea center. Case 3 represented a patient with grade 4 fovea plana associated with PAX6 mutation and poor visual acuity. OCTA revealed a disorganized pattern of large and small caliber vessels from the superficial capillary network extending into the center of the fovea.

Conclusions and importance: Previously available imaging modalities were unable to specifically target different layers of the retinal vasculature. Using OCTA we have been able to show progressive changes in the vascular pattern in the deep and superficial retinal layers of patients with different grades of fovea plana. This novel imaging technique may play a role in the classification and assessment of patients with fovea plana.

Keywords: Fovea plana; Optical coherence tomography; Optical coherence tomography angiography; PAX6 mutation.

Fig. 1

OCTA fields of view showing superficial and deep retinal capillaries (Case 1). Images from the left eye are shown. The right eye showed similar findings and is not presented. A: 3 × 3 mm optical coherence tomography angiography (OCTA) of the superficial capillary plexus. The small caliber superficial retinal capillaries are seen crossing the foveal center, with increased intercapillary spacing centrally. B: Corresponding b-scan highlighting the level of the superficial retinal OCTA (purple dashed line). A blunted foveal contour and widening of the outer nuclear layer centrally are seen. C: 3 × 3 mm OCTA of the deep capillary plexus. The deep retinal vessels extend into the fovea center with reduced density centrally. D: Corresponding b-scan highlighting the level of the deep retinal OCTA (purple dashed line). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 2

OCTA fields of view showing superficial and deep retinal capillaries (Case 2). Images from the right eye are shown. The left eye showed similar findings and is not presented. A: 3 × 3 mm optical coherence tomography angiography (OCTA) of the superficial capillary plexus. The normal orderly branching pattern is disrupted. The superficial retinal vessels are seen crossing the fovea center. B: Corresponding b-scan highlighting the level of the superficial retinal OCTA (purple dashed line). There is no foveal depression present. Widening of the outer nuclear layer centrally is seen. C: 3 × 3 mm OCTA of the deep capillary plexus. The deep retinal vessels are seen crossing the fovea center. D: Corresponding b-scan highlighting the level of the deep retinal OCTA image (purple dashed line). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 3

OCTA fields of view showing superficial and deep retinal capillaries (Case 3). Images from the left eye are shown. The right eye showed similar findings and is not presented. A: 3 × 3 mm optical coherence tomography angiography (OCTA) of the superficial capillary plexus. The vasculature is distributed in a haphazard arrangement. Both large and small caliber superficial retinal vessels are seen crossing the foveal center. B: Corresponding b-scan highlighting the level of the superficial retinal OCTA (purple dashed line). The foveal contour is absent and widening of the outer nuclear layer centrally is not seen. C: 3 × 3 mm OCTA of the deep capillary plexus. The deep retinal vessels are seen crossing the foveal center with uniform density. D: Corresponding b-scan highlighting the level of the deep retinal OCTA (purple dashed line). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)