A 21-year-old woman was referred to the Eye and ENT Hospital of Fudan University for blurred vision in the right eye for about 2 weeks. She had initially presented at her local hospital, and the doctor found a yellowish mass in the temporal peripheral retina accompanied by vitreous hemorrhage. Ocular toxocariasis was suspected and the vitreous sample was collected through the 23-G pars plana vitrectomy (PPV) 5 days later. However, the vitreous antibody to toxocariasis was negative. Her best corrected visual acuities (BCVAs) were 20/40 and 20/20 for the right and left eyes, respectively, on the arrival at our hospital. The ocular examination revealed that the temporal mass was linked to a pair of dilated vessels, however, the persistent vitreous hemorrhage obscured further details, and the left eye was apparently normal (,). The patient was suspected of retinal capillary hemangioblastoma (RCH), and a second PPV was recommended and performed about 1 month after her arrival at our hospital. During the second PPV, the remaining vitreous hemorrhage was removed, the macular epiretinal membrane was peeled off, and the RCHs were surrounded by laser photocoagulation. The patient came back 2 weeks later and complained of progressively worse vision with distortion in the left eye since the first day after the second PPV. Her BCVAs were 20/40 and 20/50 for the right and left eyes, respectively, at that moment. Mutton-fat keratic precipitates were also found bilaterally (,). Ultrawide-field photographs showed multifocal serous detachments of the retina in the posterior hole bilaterally (,). OCT (Spectralis, Heidelberg Engineering Inc., Germany) scans revealed the loss of choroidal vascular architecture, bacillary detachment, and subretinal fluids in both eyes (,). Ultrawide-field fluorescein angiography (UWFA) (Optos200Tx, Optos Plc., United Kingdom) was ordered based on the suspicion of SO. UWFA revealed hyperfluorescence of the temporal RCHs in the early phase in the right eye (). Delayed choroidal perfusion reflected by the choroidal hypofluorescence and multiple bilateral hyperfluorescent pinpoints in the posterior hole were found in the left eye (). In the late phase, the staining of the optic discs and increased subretinal pooling of fluorescence leaked from the initial pinpoints were also found (,). The patient showed no evidence of syphilis or sarcoidosis. Thus, the patient was diagnosed with SO according to the classification criteria for SO proposed by the Standardization of Uveitis Nomenclature Working Group (). The patient immediately started oral administration of prednisone (1 mg/kg per day). After about 1 week of treatment, the serous retinal detachments resolved bilaterally (,). However, the borders of the subfoveal choroid were still undetectable on enhanced depth imaging (EDI)-OCT (,). Her BCVAs improved to 20/20 after 4 months and remained stable with the gradual tapering of oral corticosteroids. On the last visit, after the treatment had been sustained for 1 year, the patient showed no sign of relapse with bilateral BCVAs of 20/20, and prednisone was completely withdrawn. We searched for any potential signs suggesting SO after the first PPV. OCTA (PLEX Elite 9000, Carl Zeiss Meditec Inc., United States) scanning was performed on the patient as a routine preoperative examination, 1 day before the second PPV, namely, 38 days after the first PPV. B scan through the fovea revealed the macular epiretinal membrane in the right eye and bilateral increased subfoveal choroidal thickness (OD = 572 μm; OS = 458 μm,,). The examinations were also followed up 3 months after the second PPV and used for self-comparison. In the present case, the choroidal thickness after corticosteroid treatment was smaller than the previous thickness (OD = 369 μm; OS = 290 μm,,). We also turned to the OCTA examination to identify any vascular changes after the first PPV. Five weeks after the first PPV, OCTA images at the level of the retina were generally normal bilaterally, except for the dilated supratemporal vein with tortuosity that was linked to the RCH beyond the scope of the posterior 12 mm × 12 mm (,). However, at the levels of both the choriocapillaris and choroid, there was a scattering of dots of flow void (,,,, refer to yellow boxes for magnified view). The B scan through these dark spots (,,,, yellow lines) confirmed the absence of the bloodstream signal beneath the RPE-Bruch membrane (,, refer to yellow boxes for magnified view). After 3 months of oral administration of prednisone, there were still no obvious retinal vascular changes (,). However, the flow void dots at the levels of both the choriocapillaris and choroid disappeared (,,,, refer to yellow boxes for magnified view). The B scan through the positions corresponding to where the flow voids had been indicated the reappearance of blood stream signal (,, refer to yellow boxes for magnified view). Moreover, on the en-face structural images of the choroid, the choroidal vessels in the parapapillary atrophic area reappeared 3 months after the second PPV (, yellow arrow), whereas 5 weeks after the first PPV, the vessel was absent in this position (, yellow arrow). The timeline in summarizes the key events and time intervals during the progression of SO. Increased SO susceptibility and severity have been reported with HLA-DR4/DQw3, HLA-DRw53 (), HLA-Cw*03, HLA-DRB1*04, HLA-DQA1*03 (), HLA-DQB1*04 (), and HLA-A11 (). We then performed the whole exome sequencing (WES) of the patient. The germline genetic mutation of VHL (c.500G > A, p.Arg167Gln) confirmed the diagnosis of VHL syndrome. The HLA typing revealed that the two alleles for HLA-A were A11, whereas all the other reported genotypes associated with SO were negative. The detailed typing of encoding genes in the Class I and Class II HLA system is provided in.