Ferromagnetic hyperthermia and iodine 125 brachytherapy in the treatment of choroidal melanoma in a rabbit model

Journal Article · Sun Oct 01 00:00:00 EDT 1989 · Archives of Ophthalmology (Chicago); (USA)

DOI:https://doi.org/10.1001/archopht.1989.01070020598048· OSTI ID:5184825

Mieler, W F; Jaffe, G J; Steeves, R A ^[1]

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1. Medical College of Wisconsin, Milwaukee (USA)

Hyperthermia has been combined with conventional radiation methods to achieve enhanced tumor destruction. We combined iodine 125 seeds with ferromagnetic thermoseeds in a single plaque to simultaneously deliver radiation and heat in a rabbit model of choroidal melanoma. Initially, six ferromagnetic thermoseeds were placed in parallel on a 14-mm episcleral plaque. The plaques were placed on normal rabbit eyes and on eyes containing transvitreally implanted choroidal melanoma. The heating response was assessed in both normal and tumor-containing eyes. Rigid copper-constantan and flexible Baily thermocouples were used to monitor temperature responses. The animals were subjected to an electromagnetic field of 100 kHz, with power of 1100 to 1500 W. The thermoseeds autoregulated at 48.2 degrees C. Scleral temperatures stabilized at 45.8 degrees C +/- 0.4 degrees C (SD), while temperatures at the base of the tumor stabilized at 43.6 degrees C +/- 0.1 degrees C. Ferromagnetic thermoseeds were then combined with iodine 125 seeds. Similar temperature responses were recorded, and autoradiographic findings confirmed a uniform radiation distribution. Varying the amount or type of ferromagnetic material in the thermoseeds allows the delivery of heat at virtually any temperature. Ferromagnetic hyperthermia may provide a more simplified approach over currently available methods of heat delivery.

• OSTI ID: 5184825
• Journal Information: Archives of Ophthalmology (Chicago); (USA), Vol. 107:10; ISSN 0003-9950
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
EYES
MELANOMAS
HYPERTHERMIA
RADIOSENSITIVITY EFFECTS
RADIOTHERAPY
AUTORADIOGRAPHY
IODINE 125
RABBITS
RADIATION SOURCE IMPLANTS
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
BODY AREAS
BODY TEMPERATURE
DAYS LIVING RADIOISOTOPES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
FACE
HEAD
IMPLANTS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPES
MAMMALS
MEDICINE
NEOPLASMS
NUCLEAR MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIATION SOURCES
RADIOISOTOPES
RADIOLOGY
SENSE ORGANS
THERAPY
VERTEBRATES
550604* - Medicine- Unsealed Radionuclides in Therapy- (1980-)