ObjectiveTo observe the abnormal clinical manifestations of retinal blood vessels and the characteristic image characteristics of optical coherence tomography (OCT) in young myopia. MethodsA case observation study. From July to December 2020, 523 young patients with different myopia refractive powers who were treated in Department of Ophthalmology of The Second Hospital of Hebei Medical University were included in the study. Among them, 277 were males and 246 were females; the median age was 19.0 (5.0) years. All the affected eyes underwent best corrected visual acuity (BCVA), frequency domain OCT (SD-OCT) examination and axial length (AL) measurement. The BCVA examination was performed using the Snellen eye chart. The median myopia refractive power of the affected eye was 5.00 (3.25) D. Among them, low myopia, moderate myopia, and high myopia were 227, 405, and 414 eyes, respectively. The average AL of the affected eye was 25.6±2.8 mm. The frequency domain OCT instrument was used to scan the temporal side of the retina, the upper and lower nasal vascular arches and the macular fovea radially. The images of retinal vascular cysts, microfolds, and lamellar hole were acquired and stored. The prevalence, composition ratio, distribution rule and OCT imaging characteristics of retinal paravascular abnormalities were observed and analyzed. The distribution of paravascular abnormalities in the retina was compared by the χ2 test; the age, refractive power, and AL of different paravascular abnormalities were compared by the K-W rank sum test. ResultsOf the 1046 different diopters of myopic eyes, there were 227 eyes in mild myopia, 405 eyes in moderate myopia and 414 eyes in high myopia. Retinal paravascular abnormalities were detected by SD-OCT in 40 eyes (3.8%,40/1046). The prevalence of retinal paravascular abnormalities in moderate myopia was 0.7% (3/405) and high myopia was 8.9% (37/414). No retinal paravascular abnormalities were observed in mild myopia.Retinal paravascular cysts in 40 eyes (3.8%, 40/1046), retinal paravascular microfolds in 28 eyes (2.7%, 28/1046) and retinal paravascular lamellar holes in 13 eyes (1.2%, 13/1046). Of 40 eyes with retinal paravascular abnormalities, retinal paravascular cysts in all 40 eyes (100.0%, 40/40), retinal paravascular microfolds in 28 eyes (70.0%, 28/40) and retinal paravascular lamellar holes in 13 eyes (32.5%, 13/40). Twelve eyes with simple cyst cavity (30.0%, 12/40); 15 eyes were with cyst cavity with micro-wrinkles (37.5%, 15/40); 13 eyes were with cyst cavity, micro-wrinkles and lamellar holes (32.5%, 13/40). The temporal vascular arch retinal paravascular cysts (χ2=25.664), microfolds (χ2=14.973), and lamellar holes (χ2=13.499) were significantly more than those on the nasal side, and the difference was statistically significant (P＜0.001). ConclusionsThe total prevalence of retinal paravascular abnormalities in young myopia is 3.8%; it can occur in both moderate and high myopia. The paravascular cyst may be the earliest pathology of paravascular abnormalities in the retina. The three paravascular abnormalities are mostly distributed along the temporal arch of the retina.