Familial retinal arteriolar tortuosity and quantification of vascular tortuosity using swept-source optical coherence tomography angiography

Abstract

PurposeFamilial retinal arteriolar tortuosity (FRAT) is a rare autosomal dominant disorder that is characterized by tortuosity of the second and higher order retinal arterioles. We implement swept-source optical coherence tomography angiography (SS-OCTA) to quantify vessel tortuosity in patients with FRAT. We hypothesize that patients with FRAT will have higher retinal arteriole tortuosity when compared to controls.MethodsPatients were scanned with a SS-OCTA device (Plex Elite 9000, Carl Zeiss Meditec, Dublin, CA). Images of a 12 × 12 mm2 area centered on the fovea were processed, and retinal vessels >23.5 μm in diameter were identified. An automatic tortuosity measurement program written in MATLAB was used to assess vessel tortuosity. Branch points in the vessels were detected and used to separate the vasculature into individual segments. The tortuosity was measured by calculating the arc-chord ratio of each vessel segment, where a minimum value of 1 indicated a straight vessel and higher values corresponded to increasing tortuosity.ResultsTwo patients (4 eyes) with a known history of FRAT and six controls (12 eyes) were enrolled in the study. The mean tortuosity of all vessel segments (MTVS) in scans of FRAT eyes was on average 1.1244 [range: 1.1044–1.1438] while for control eyes it was 1.0818 [range: 1.0746–1.0872]. Average MTVS of FRAT eyes was significantly higher compared to control eyes (p = 0.03).Conclusions and ImportanceOur results are consistent with the hypothesis that patients with FRAT have higher objective measurements of tortuosity compared to controls. Broader applications of this method may be of benefit in other retinal diseases with changes in retinal vessel configuration.

Optic Disc Features in Familial Retinal Arteriolar Tortuosity

“…With the help of retinal vessel oximetry we were able to confirm more precisely that all affected retinal and peripapillary vessels are of arterial origin, a finding never described before. It is, however, not an unexpected finding as based on published data on fluorescein angiography and OCTA, second-and third-order retinal arteries should primarily be affected [3].…”

A Rare Coexistence of Isolated Unilateral Conjunctival Telangiectasia and Retinal Vascular Tortuosity

“…Retinal arterioles typically appear in corkscrew and spiral shapes and can lead to recurrent visual symptoms complicated by preretinal and intraretinal hemorrhages [ 15 ]. Systemic involvement of nonocular vascular beds has been demonstrated in a few cases [ 16 ]. However, the diagnosis is mainly based on clinical findings of bilateral tortuosity of small and medium-sized arterioles in the peripapillary and macular regions contrary to our patient which has unilateral involvement.…”

Optical coherence tomography angiography reveals progressive worsening of retinal vascular geometry in diabetic retinopathy and improved geometry after panretinal photocoagulation

“…Vessel tortuosity was estimated as the ratio between the sum of the actual length of all the vessels and the sum of their Euclidean distance length (Fig 1). [32, 33] Retinal tortousity, quantified using the Euclidean distance, has been used to study peripapillary and bulbar conjunctival vessel tortuosity in diabetic retinopathy[7, 34], correlation between retinal vascular tortuosity in diabetic retinopathy and renal disease[11], sickle cell retinopathy[35], characterization of familial retinal arteriolar tortuosity [36], and diagnosis and quantification of plus disease in retinopathy of prematurity. [37, 38]…”