Inclusion Criteria:
Subjects who meet all of the following inclusion criteria may be eligible to participate in this study:
* The subject voluntarily signs the written informed consent form and is willing to comply with the long-term follow-up protocol and companion protocol;
* Clinically diagnosed with Bietti's crystalline dystrophy (BCD) (aged ≥ 18 years);
* Confirmed by genetic testing to carry biallelic mutations in the CYP4V2 gene, with no pathogenic mutations of other ophthalmic genetic diseases;
* The subject and their spouse agree to use highly effective barrier contraception during the trial and for 2 years after drug administration;
* The study eye must meet the following requirements:
1. Best-corrected visual acuity (BCVA) ≥ 0.5 LogMAR (equivalent to decimal visual acuity ≤ 0.3);
2. No refractive media turbidity that affects fundus examination, and the subject must be able to undergo visual and retinal function assessments;
3. Visible photoreceptor layer (outer nuclear layer) in the macular area on standard optical coherence tomography (OCT) scans.
* \*Defination of the study eye: For all subjects, only one eye is designated as the "study eye" (i.e., the eye receiving treatment). If both eyes of a subject meet the inclusion criteria, the eye with poorer visual acuity is selected as the study eye. If both eyes are affected equally, the right eye is selected as the study eye.
Exclusion Criteria:
Subjects meeting any of the following criteria will be excluded from the study:
* Insufficient viable retinal photoreceptors, as determined by OCT or ophthalmoscopy.
* The investigator determines that the study eye has or has had choroidal neovascularization (CNV) secondary to BCD.
* Received other treatments within 3 months prior to screening that could affect the evaluation of the investigational drug's results (e.g., ranibizumab, bevacizumab, aflibercept, conbercept, triamcinolone acetonide, steroids, etc.).
* The study eye has previously undergone intraocular surgeries, such as retinal reattachment surgery or vitrectomy.
* Presence of other ocular diseases that may interfere with the surgical procedure or complicate the interpretation of study endpoints or surgical complications (e.g., glaucoma, diabetic retinopathy, or retinal vasculitis).
* Currently using, or potentially requiring, systemic medications known to cause ocular toxicity (e.g., psoralen, risedronate, or tamoxifen).
* History of hypersensitivity or allergic constitution (e.g., allergy to two or more drugs or foods).
* Clinically significant abnormal laboratory findings, including:
1. Liver function: Chronic liver disease, or ALT elevation \> 3 times the upper limit of normal (ULN).
2. Uncontrolled hypertension, defined as mean systolic blood pressure (SBP) ≥ 160 mmHg or mean diastolic blood pressure (DBP) ≥ 100 mmHg.
3. Uncontrolled diabetes mellitus, defined as HbA1c \> 10%.
4. Abnormal coagulation function, defined as prothrombin time (PT) ≥ ULN + 3 seconds, or activated partial thromboplastin time (aPTT) ≥ ULN + 10 seconds.
5. Positive serology for Hepatitis B surface antigen (HBsAg), Hepatitis C virus antibody (HCV-Ab), human immunodeficiency virus antibody (HIV-Ab), or syphilis antibody.
6. Abnormalities in tumor markers (alpha-fetoprotein, carcinoembryonic antigen, CA125, CA153, or CA199).
* Any past or present medical history that may affect the safety of the trial or the in vivo process of the drug, especially clinically significant cardiovascular, hepatic, renal, endocrine, gastrointestinal, pulmonary, neurological, hematological, oncologic, immunological, or metabolic disorders (e.g., severe heart failure \[NYHA Class III and IV\], cor pulmonale, etc.), as determined by the investigator.
* Participation in any drug or medical device clinical trial within 3 months prior to screening.
* Immunologic testing reveals neutralizing antibodies to rAAV \> 1:1000.
* Pregnant or lactating women.
* Any other conditions that, in the investigator's opinion, render the participant unsuitable for this clinical trial.
