Portrait de Shirin A. Enger

Shirin A. Enger

Membre affilié
Professeure titulaire, McGill University, Département d'oncologie
Sujets de recherche
Apprentissage automatique médical
Apprentissage multimodal
Apprentissage profond
Curiethérapie
IA en santé

Biographie

Shirin Abbasinejad Enger est professeure agrégée à l'Unité de physique médicale du Département d'oncologie Gerald Bronfman de l’Université McGill, directrice de l'Unité de physique médicale et titulaire d'une chaire de recherche du Canada de niveau 2 en physique médicale. Elle est également chercheuse principale à l'Institut Lady Davis de recherches médicales et au Centre de cancérologie Segal de l'Hôpital général juif. Mme Enger a obtenu un doctorat de l'Université d'Uppsala en 2009 et a été boursière postdoctorale à l'Université Laval de 2009 à 2011. Elle a joué un rôle de premier plan au sein de plusieurs groupes de travail et comités nationaux et internationaux.

Étudiants actuels

Doctorat - McGill
Doctorat - McGill
Doctorat - McGill
Doctorat - McGill
Doctorat - McGill
Doctorat - McGill

Publications

Investigating Alpha-DaRT Source Daughter Diffusion in Intra-Rectal Animal Models
Mélodie Cyr
Behnaz Behmand
Naim Chabaytah
Joud Babik
Mirta Dumancic
Joanna Li
Guillaume St-Jean
Penalty weight tuning in high dose rate brachytherapy using multi-objective Bayesian optimization
Majd Antaki
Marie Duclos
Farhard Maleki
Shirin A Enger
Objective. Treatment plan optimization in high dose rate brachytherapy often requires manual fine-tuning of penalty weights for each objecti… (voir plus)ve, which can be time-consuming and dependent on the planner's experience. To automate this process, this study used a multi-criteria approach called multi-objective Bayesian optimization with q-noisy expected hypervolume improvement as its acquisition function (MOBO-qNEHVI). Approach. The treatment plans of 13 prostate cancer patients were retrospectively imported to a research treatment planning system, RapidBrachyMTPS, where fast mixed integer optimization (FMIO) performs dwell time optimization given a set of penalty weights to deliver 15 Gy to the target volume. MOBO-qNEHVI was used to find patient-specific Pareto optimal penalty weight vectors that yield clinically acceptable dose volume histogram metrics. The relationship between the number of MOBO-qNEHVI iterations and the number of clinically acceptable plans per patient (acceptance rate) was investigated. The performance time was obtained for various parameter configurations. Main results. MOBO-qNEHVI found clinically acceptable treatment plans for all patients. With increasing the number of MOBO-qNEHVI iterations, the acceptance rate grew logarithmically while the performance time grew exponentially. Fixing the penalty weight of the tumour volume to maximum value, adding the target dose as a parameter, initiating MOBO-qNEHVI with 25 parallel sampling of FMIO, and running 6 MOBO-qNEHVI iterations found solutions that delivered 15 Gy to the hottest 95% of the clinical target volume while respecting the dose constraints to the organs at risk. The average acceptance rate for each patient was 89.74% ± 8.11%, and performance time was 66.6 ± 12.6 s. The initiation took 22.47 ± 7.57 s, and each iteration took 7.35 ± 2.45 s to find one Pareto solution.Significance. MOBO-qNEHVI combined with FMIO can automatically explore the trade-offs between treatment plan objectives in a patient specific manner within a minute. This approach can reduce the dependency of plan quality on planner’s experience and reduce dose to the organs at risk.
Dosimetry of [18F]TRACK, the first PET tracer for imaging of TrkB/C receptors in humans
Alexander Thiel
Alexey Kostikov
Hailey Ahn
Youstina Daoud
Jean-Paul Soucy
Stephan Blinder
Carolin Jaworski
Carmen Wängler
Björn Wängler
Freimut Juengling
Ralf Schirrmacher
Background Reduced expression or impaired signalling of tropomyosin receptor kinases (Trk receptors) are found in a vast spectrum of CNS dis… (voir plus)orders. [^18F]TRACK is the first PET radioligand for TrkB/C with proven in vivo brain penetration and on-target specific signal. Here we report dosimetry data for [^18F]TRACK in healthy humans. 6 healthy participants (age 22–61 y, 3 female) were scanned on a General Electric Discovery PET/CT 690 scanner. [^18F]TRACK was synthesized with high molar activities (A_m = 250 ± 75 GBq/µmol), and a dynamic series of 12 whole-body scans were acquired after injection of 129 to 147 MBq of the tracer. Images were reconstructed with standard corrections using the manufacturer’s OSEM algorithm. Tracer concentration time-activity curves (TACs) were obtained using CT-derived volumes-of-interest. Organ-specific doses and the total effective dose were estimated using the Committee on Medical Internal Radiation Dose equation for adults and tabulated Source tissue values (S values). Results Average organ absorbed dose was highest for liver and gall bladder with 6.1E−2 (± 1.06E−2) mGy/MBq and 4.6 (± 1.18E−2) mGy/MBq, respectively. Total detriment weighted effective dose E_DW was 1.63E−2 ± 1.68E−3 mSv/MBq. Organ-specific TACs indicated predominantly hepatic tracer elimination. Conclusion Total and organ-specific effective doses for [^18F]TRACK are low and the dosimetry profile is similar to other ^18F-labelled radio tracers currently used in clinical settings.