title: Evaluation of different magnetic resonance imaging contrast materials to be used as dummy markers in image-guided brachytherapy for gynecologic malignancies.
abstract: OBJECTIVE
  To identify a contrast material that could be used as a dummy marker for magnetic resonance imaging.
  
  
  METHODS
  Magnetic resonance images were acquired with six different catheter-filling materials-water, glucose 50%, saline, olive oil, glycerin, and copper sulfate (CuSO4) water solution (2.08 g/L)-inserted into compatible computed tomography/magnetic resonance imaging ring applicators placed in a phantom made of gelatin and CuSO4. The best contrast media were tested in four patients with the applicators in place.
  
  
  RESULTS
  In T2-weighted sequences, the best contrast was achieved with the CuSO4-filled catheters, followed by saline- and glycerin-filled catheters, which presented poor visualization. In addition (also in T2-weighted sequences), CuSO4 presented better contrast when tested in the phantom than when tested in the patients, in which it provided some contrast but with poor identification of the first dwell position, mainly in the ring.
  
  
  CONCLUSIONS
  We found CuSO4 to be the best solution for visualization of the applicator channels, mainly in T2-weighted images in vitro, although the materials tested presented low signal intensity in the images obtained in vivo, as well as poor precision in determining the first dwell position.
authors.affiliation: PhD, Medical Physicist, Radiotherapy Department, Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InRad/HC-FMUSP), São Paulo, SP, Brazil.
authors.forename: Camila Pessoa
authors.initials: CP
authors.lastname: Sales
authors.affiliation: PhD, Medical Coordinator of the Radiotherapy Department, Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InRad/HC-FMUSP), São Paulo, SP, Brazil.
authors.forename: Heloisa de Andrade
authors.initials: Hde A
authors.lastname: Carvalho
authors.affiliation: MSc, Medical Physicist, LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Department of Radiology and Oncology, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil.
authors.forename: Khallil Chaim
authors.initials: KC
authors.lastname: Taverna
authors.affiliation: PhD, Medical Physicist, LIM/44 - Laboratório de Ressonância Magnética em Neurorradiologia, Department of Radiology and Oncology, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil.
authors.forename: Bruno Fraccini
authors.initials: BF
authors.lastname: Pastorello
authors.affiliation: MSc, Medical Physicist, Radiotherapy Department, Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InRad/HC-FMUSP), São Paulo, SP, Brazil.
authors.forename: Rodrigo Augusto
authors.initials: RA
authors.lastname: Rubo
authors.affiliation: BA, Medical Physicist at Royal Philips Electronics, Eindhoven, the Netherlands.
authors.forename: Arthur Felipe
authors.initials: AF
authors.lastname: Borgonovi
authors.affiliation: MD, Physician in the Division of Radiotherapy, Department of Radiology and Oncology, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, SP, Brazil.
authors.forename: Silvia Radwanski
authors.initials: SR
authors.lastname: Stuart
authors.affiliation: PhD, Medical Physicist, Radiotherapy Department, Instituto de Radiologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (InRad/HC-FMUSP), São Paulo, SP, Brazil.
authors.forename: Laura Natal
authors.initials: LN
authors.lastname: Rodrigues
keywords: Brachytherapy/methods; Contrast media; Diagnostic techniques, obstetrical and gynecological; Imaging, three-dimensional; Magnetic resonance imaging/methods