Pilot Study on the Feasibility of High-energy Collimation With Optimized Geometry on a VERITON™ CZT Camera

Functional imaging using scintigraphy plays a major role in the diagnosis and monitoring of many diseases, particularly thanks to its ability to perform whole-body examinations with high contrast. The indications and use of scintigraphy have increased in recent years, particularly in connection with the development of internal vectorized radiotherapy. This therapeutic approach is based on the administration of radiotracers that enable targeted irradiation of tumor cells, whose biodistribution throughout the body can be analyzed and quantified using scintigraphy, particularly with iodine-131 and lutetium-177.

The recent boom in scintigraphy is also linked to the development of new 360° geometry CZT-SPECT cameras, which enable rapid tomographic acquisitions of the entire body with significantly improved image quality compared to conventional cameras. These systems use mobile CZT semiconductor detectors that dynamically scan the anatomical regions of interest.

CZT detectors are combined with a collimation system consisting of tungsten septa, which are essential for the directional filtering of gamma photons. Unlike conventional scintigraphic cameras, where collimators can be changed or adjusted according to the energy of the detected photons, CZT-SPECT 360° cameras generally rely on fixed collimation, which cannot be changed.

Inclusion criteria

• patients with multiple known lesions (≥ 2 metastases or lesions of other types) who, as part of their clinical management, require either (i) a 99mTc-HDP bone scan, or (ii) a post-therapeutic 177Lu-PSMA scan, or (iii) a post-therapeutic 131I scintigraphy.
• Person who has undergone a preliminary clinical examination appropriate for clinical research.
• Adult subject who has received complete information about the research and has signed the informed consent form.
• General condition, WHO ≤ 2, and ability to remain lying down without moving for nearly an hour.

Exclusion criteria

• Subjects with a contraindication, according to the target examination group, to injection of 99mTc-HDP (Technescan HDP, Curium Pharma), 177Lu-PSMA (Pluvicto®, Novartis), or 131I (131I sodium iodide for therapy, Curium Pharma) .
• Subjects covered by Articles L. 1121-5, L. 1121-7, and L1121-8 of the Public Health Code.
• Pregnant women, women in labor, or breastfeeding mothers.
• Subjects subject to legal protection measures (guardianship, curatorship, judicial protection).
• Subjects unable to give their consent.
• Subjects deprived of their liberty by a judicial or administrative decision, persons receiving psychiatric care pursuant to Articles L. 3212-1 and L.3213-1.