The purpose of this study is to evaluate the efficacy and safety of HRS-9231 for Central Nervous System (CNS) Magnetic Resonance Imaging (MRI); to explore the effective dose of HRS-9231 for CNS MRI; and to explore the population pharmacokinetic characteristics of HRS-9231 in CNS MRI subjects

Inclusion Criteria:

1. Sign the informed consent form, willing to cooperate with the study, and comply with trial requirements
2. Age ≥18 years, no gender restrictions
3. Known or highly suspected CNS lesions, with imaging showing at least one enhanced lesion
4. Scheduled for CNS contrast-enhanced MRI for clinical needs and agree to complete two contrast-enhanced MRI scans

Exclusion Criteria:

1. Clinically unstable condition or severe diseases that may affect trial results, such as inability to ensure imaging comparability or reliability of study parameters
2. Moderate to severe renal dysfunction, defined as aGFR < 60 mL/min
3. Contraindications to MRI, such as metallic implants or claustrophobia
4. History of severe allergies, including drugs, contrast agents, or other allergens
5. Severe liver disease or cardiovascular disease, or related abnormal test results
6. Central nervous system inflammation or recent history of stroke
7. Active infectious diseases, such as HIV, hepatitis B, or syphilis
8. Use of other contrast agents before or after study drug administration, or recent interventional treatments that may affect imaging comparability
9. Pregnancy, breastfeeding, or plans for conception, without effective contraception measures
10. Recent participation in other clinical trials or previous participation in studies involving gadolinium-based contrast agents
11. Other conditions deemed unsuitable by the investigator