The imaging features of optical coherence tomography angiography of complex retinal arterial macroaneurysms

Abstract

Objective To observe the imaging features of the optical coherence tomography angiography (OCTA) of complex retinal arterial macroaneurysm (RAM). Methods Nineteen eyes of 19 patients with RAM were enrolled in this retrospective study. There were 1 male (1 eye) and 18 females (18 eyes). The patients aged from 62 to 85 years, with the mean age of 71.3 years. The fundus photography examination revealed the tumors were located in the 1 - 3 branch of the artery, which showed focal spindle-shaped or fusiform angiomatous dilatation. The fundus fluorescein angiography revealed the early uniform fluorescence of the tumor, and the tumor was a high-fluorescence leak in the late period. RAM was divided into exudative type and hemorrhagic type according to the literature and based on the ocular fundus appearance. In 19 eyes, 8 eyes were exudative RAM and 11 eyes were hemorrhagic RAM. All eyes were examined by OCTA, and the retinal blood flow images of 3 mm ×3 mm diameter were routinely collected to observe the OCTA imaging features. Results OCTA examination showed that the superficial RAM of all eyes had strong reflection signal connected with retinal artery. B-scan image showed smaller tumors in the lumen with strong reflection of expansion, or large tumor with peak-like uplift and the blood flow signals in the tumor body were abundant. The enface image clearly showed the three-dimensional shape of the tumor. Tumors with exudation or multi-level bleeding could be clearly documented for their bleeding range and boundary. The white signal co-localized with the superficial retinal blood vessels by the function of multi-color fluoroscopy. The pattern of blood flow density can also clearly show the three-dimensional shape of the tumor. Conclusion The complex RAM is a strong reflection signal in the superficial layer of retina, which is connected with the retinal vessels; B-scan images shows small tumors with a small piece of strong reflection and dilation, or large tumors with mountain-like elevation with abundant blood flow signals. En face image can clearly show the three-dimensional shape of the tumor. Key words: Retinal aneurysms/diagnosis; Retinal diseases/diagnosis; Optical coherence tomography; Local blood flow