Study 22403 is a Phase 1 / Proof of Concept exploratory investigation to assess the non-inferiority of low dose gadobutrol and SubtleGAD™, a software medical device using an Artificial Intelligence (AI) deep learning-based method to enhance the contrast signal from images acquired with low dose administration of gadobutrol (GAD) contrast. The primary objective is to demonstrate noninferiority of synthesized Central Nervous System (CNS) magnetic resonance (MR) images for 1 or 2 different gadobutrol-enhanced low-dose groups (0.01mmol/kg, and0.025 mmol/kg) compared to gadobutrol-enhanced CNS MR images at a standard dose of 0.1 mmol/kg. This investigation is a prospective, randomized, open label, multi-center study with blinded reads in participants with known or highly suspected CNS pathology. There will be at least 60 participants enrolled (30 per study arm). SubtleGAD will be used as a post-processing tool, prior to blinded read assessment of MR images acquired in either arm of the study.

Inclusion Criteria:

1. At the time of signing the informed consent at least 18 years of age and less than or equal to 89 years of age.
2. Have known or highly suspected brain lesions referred for contrast-enhanced MRI of the CNS.
3. Have an estimated glomerular filtration rate (eGFR) value ≥ 60 mL/min/1.73m^2.
4. Be fully informed about the study, including provisions of the Health Insurance Portability and Accountability Act (HIPAA) as applicable, and being capable and willing to consent to participate.

Exclusion Criteria:

1. Considered clinically unstable or has a concomitant/intercurrent condition that would not allow participation in the study.
2. Diagnoses of multiple sclerosis or other disease process that is expected to change its enhancement pattern in the time period of the follow-up.
3. Brain pathology or abnormalities that are not considered lesions.
4. Any contraindication for MRI procedure or gadobutrol administration.
5. Has severe cardiovascular disease.
6. Is expected or is scheduled to have a change in any treatment or procedure between the two study periods that may alter image comparability.
7. Is scheduled or is likely to require a biopsy or any interventional therapeutic procedure from the first study MRI up to 24 hours after the second study MRI.
8. Women currently lactating, pregnant, or planning on becoming pregnant during the study.
9. Women of childbearing potential with a positive urine pregnancy test within 24 hours before either gadobutrol administration.
10. Receipt of any gadolinium-based contrast agent <72 hours prior to the study MRIs.
11. Participants with acute kidney injury.