The design and the dosimetry of bi-nuclide radioactive ophthalmic applicators.
A novel type of applicator for the treatment of intra-ocular tumors has been developed, based on the two radionuclides 106Ru/106Rh and 125I. The dose distribution of this ophthalmic plaque combines advantageous features of both radionuclides and can be optimally adapted to a tumor thickness in the range 6.5-9 mm, a size which is beyond the dosimetric limitations of the 106Ru/106Rh plaque therapy. Compared with 125I plaques a bi-nuclide plaque allows to maintain the tumor dosage while the dose in the irradiated volume outside of the target volume is significantly reduced. Consequently, radiosensitive structures within the eye can be spared more effectively. Dedicated methods have been developed for the dosimetry of this plaque. These methods are based on our own extensive dosimetric investigations with plastic scintillators. The precondition was the availability, developed in recent years, of a more accurate determination of the absolute dose rate to water of beta- and low energy emitters.
Flühs
Dirk
D
University Hospital Essen, Department of Radiotherapy, Hufelandstr. 55, D-45122 Essen, Germany. dirk.fluehs@uni-essen.de
Anastassiou
Gerasimos
G
Wening
Jan
J
Sauerwein
Wolfgang
W
Bornfeld
Norbert
N
D055592:Biophysical Phenomena; D001703:Biophysics; D001918:Brachytherapy / Q000295:instrumentation*; D004867:Equipment Design; D005134:Eye Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D011868:Radioisotopes / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D012238:Rhodium / Q000627:therapeutic use; D012429:Ruthenium Radioisotopes / Q000627:therapeutic use
D007457:Iodine Radioisotopes; D011868:Radioisotopes; D012429:Ruthenium Radioisotopes; D012238:Rhodium