Correlation of Outer Retinal Degeneration and Choriocapillaris Loss in Stargardt Disease Using En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

Abstract

Purpose: Measure and correlate degeneration of the inner segment/outer segment junction (IS/ OS), retinal pigment epithelium (RPE) and choriocapillaris (CC) in Stargardt disease (STGD) Design: Prospective cross-sectional study Methods Setting: Casey Eye Institute Population: 23 patients with STGD Procedures: OCT angiography (OCTA) scans were centered on the fovea. OCT slab projection and en face boundary maps were used to create masks to measure total IS/OS loss or RPE atrophy, as well as regions of isolated IS/OS loss, isolated RPE atrophy, matched IS/OS and RPE degeneration, or intact IS/OS and RPE. CC vascular density (CCVD) was quantified from CC angiogram. Outcome Measures: Area of loss and CCVD for different region types of degeneration were quantified and correlated. Results: The total area of IS/OS loss was strongly correlated with total area of RPE atrophy (r=0.96, p<0.0001) by a ratio of 1.6:1 (r 2 =0.90). CCVD within regions of matched degeneration

Optical Coherence Tomography Angiography Imaging in Inherited Retinal Diseases

“…Mastropasqua and coauthors reported decreased vessel densities in the superficial capillary plexus (parafoveal), deep capillary plexus (foveal and parafoveal), and choriocapillaris (foveal and parafoveal), in STGD eyes when compared to controls [41]. Alabduljalil compared 23 STGD patients and 10 normal patients, and found a lower total choriocapillaris vessel density in STGD patients (92.0 ± 0.2) than normal subjects (99.0 ± 0.19, p = 0.0044) [42]. The total choriocapillaris vessel density was also found to be correlated with greater areas of total inner segment/outer segment photoreceptor (IS/OS) loss, total retinal pigment epithelium (RPE) loss, matched degeneration, and isolated IS/OS loss, but not with isolated RPE atrophy [42].…”

“…Alabduljalil compared 23 STGD patients and 10 normal patients, and found a lower total choriocapillaris vessel density in STGD patients (92.0 ± 0.2) than normal subjects (99.0 ± 0.19, p = 0.0044) [42]. The total choriocapillaris vessel density was also found to be correlated with greater areas of total inner segment/outer segment photoreceptor (IS/OS) loss, total retinal pigment epithelium (RPE) loss, matched degeneration, and isolated IS/OS loss, but not with isolated RPE atrophy [42]. These data suggested that choriocapillaris atrophy was significantly associated with photoreceptor and RPE atrophy.…”

Progressive Choriocapillaris Impairment in ABCA4 Maculopathy Is Secondary to Retinal Pigment Epithelium Atrophy

“…[21][22][23][24] Currently, OCTA has become the primary modality to analyze the retinal and choroidal vasculature in a variety of retinal dystrophies, including retinitis pigmentosa, choroideremia, and STGD. 5,[11][12][13][14][15]25 In STGD, studies by Mastropasqua et al 12 and Battaglia Parodi et al 13 reported vascular impairments at the levels of the superficial capillary, deep capillary plexus, and CC. Furthermore, Alabduljalil et al 5 reported a strong correlation between the area of RPE atrophy on SW-AF imaging and loss of the inner and outer segment junction on SD-OCT, concluding that photoreceptor degeneration precedes RPE atrophy.…”

“…5,[11][12][13][14][15]25 In STGD, studies by Mastropasqua et al 12 and Battaglia Parodi et al 13 reported vascular impairments at the levels of the superficial capillary, deep capillary plexus, and CC. Furthermore, Alabduljalil et al 5 reported a strong correlation between the area of RPE atrophy on SW-AF imaging and loss of the inner and outer segment junction on SD-OCT, concluding that photoreceptor degeneration precedes RPE atrophy. A smaller study by de Carlo et al 14 examined seven patients with retinal dystrophies, including four with STGD, and concluded that because CC changes were smaller than the corresponding RPE alterations, vascular loss is a secondary process.…”

“…9,10 Recently, optical coherence tomography angiography (OCTA) has been increasingly used to analyze the retinal and choroidal vasculatures in the study of retinal dystrophies. 5,[11][12][13][14][15] OCTA uses streaming blood flow to create an image showing the retinal vasculature. Individual choriocapillaris (CC) vessels are not visualized, but rather appear as homogeneous with areas of brightness representing blood flow.…”