It may seem that this paper is very far from our interest. But it is not very far from Stamler's earlier interest. This PET probe was developed from
dihydrotetrabenazine (DTBZ), a tetrabenazine derivative. Stamler has many papers about TBZ as this:

Safety of Converting From Tetrabenazine to Deutetrabenazine for the Treatment of Chorea

Dihydrotetrabenazine demonstrates high specificity and affinity for VMAT2, vesicular monoamine transporter type 2 (VMAT2).

Then we come to the iron and MRI images. The correlation between iron and α-Syn forms the basis for combining PET and QSM. 18F-AV133 PET detects molecular-level metabolic changes in PD, reflecting α-Syn aggregation, while QSM directly quantifies iron deposition in the brains of PD patients.

This is a chapter from the introduction: "The correlation between iron and α-Syn forms the basis for combining PET and QSM. 18F-AV133 PET detects molecular-level metabolic changes in PD, reflecting α-Syn aggregation, while QSM directly quantifies iron deposition in the brains of PD patients. This combination provides critical and complementary information on the pathophysiological changes in PD".

Here is a sentence from the conclusion: "The findings suggest that changes in VMAT2 distribution in the Ca (caudate) and Apu (anterior putamen) can be used to assess NMS (non-motoric symptoms) of PD, while the PPu (posterior putamen) is useful for evaluating motor symptoms. Additionally, the QSM value of the SN progressively increases with disease progression, making it a sensitive tool for evaluating both motor and non-motor symptoms in PD.