Induction heating can be utilized to cause necrosis of neoplasm as a result of hyperthermia by a process involving the injection of particles having hysteresis heating characteristics into tissue either within or in close proximity to the neoplasm and then subjecting these particles to an alternating magnetic field sufficient to cause hysteresis heating. The frequency of the field is preferably sufficiently low so as to minimize eddy current and dielectric heating. The particles used are preferably initially located within a biologically inert liquid carrier which will facilitate the insertion of the particles within the body and which will automatically become non-liquid within the body so as to hold the particles in place. The carrier may contain radiopaque material to enhance its visualization under radiographic examination. The actual heating is preferably carried out by positioning either the entire patient or the affected portion of the patient's body through a series of axially aligned, parallel, liquid cooled coils. Only one of these coils is connected to a power supply.
A heater (seed) and system for subjecting body tissue to closely controlled hyperthermia or higher temperatures includes a core of ferromagnetic material having a high resistivity or resistivity of a non-conductor enclosed with a bio-compatible non-magnetic conductive sheath and excited by a coil positioned to establish a magnetic field coupled to the seed. The core is dimensioned so as to reduce demagnetizing effects to acceptable levels. The thickness of the conductive sheath is optimized to maximize heat generation to achieve a heat generating capacity which is considerably greater than that of the bare ferromagnetic material.
A method and apparatus for influencing a biological material, both being intended to influence such characteristics are correlated with the occurrence of natural atmospherics, i.e., the proliferation rate of C6-glioma cells and the survival time of Yoshida-ascites-hepatoma rats. For this purpose, signals representing the time history of the magnetic field of certain natural atmospherics are stored, which are identified by means of distinctly pronounced frequency fractions, e.g., 10 kHz. Using these signals, corresponding magnetic field variations are reproduced as artificial atmospherics. Reproduction is effected, e.g., in a Helmholtz coil. The biological material is exposed to this magnetic field.
The subject of this invention is in the field of medicine, particularly surgery, and is intended for the treatment of benign tumors and angiomas. A hemangioma is an angioma, or tumor, formed by an anomalous proliferation of vascular endothelium, forming an undesirable mass, which can occur anywhere in the body. The resulting disease is known as hemangiomatosis. The method of this invention is comprised of a reduction of the arterial blood flow to the hemangioma which limits the blood circulation in the tumor mass, thus creating favorable conditions for subsequent ferromagnetic embolization from externally and selectively applied electromagnetic or ultrasound energy and sclerotization of the tumor tissue, preventing the spread of ferromagnetic particles through the vessels and into other organs and systems. At the same time, maintaining the blood flow, though reduced, prevents the development of a total necrosis due to acute impairment of the tumor's blood circulation, which significantly reduces the general toxic effect. The reduced blood stream still leaves the possibility of introducing medication into the tumor, which reduces the possibility of complications during the postembolization period.
The present invention provides an improved method for treatment of diseased tissue, which comprises the steps of: (i) selecting at least a magnetic material which has a magnetic heating efficiency of at least about 4.5.times.10.sup.-8 J.m./A.g, when rotational magnetic field conditions are equal to or less than about 5.times.10.sup.8 A/m.s; (ii) delivering the magnetic material to a patient's diseased tissue; and (iii) exposing the magnetic material to a rotational magnetic field with a frequency of greater than about 10 kHz and a field strength selected such that the product of field strength, frequency and the radius of the exposed region is less than about 7.5.times.10.sup.7 A/s to generate hysteresis heat in the diseased tissue.
The present invention describes a method for the treatment of neurological diseases and development and neuromuscular diseases and development with diagnostic applications to optimize the treatment modalities. The process involves the use of magnetic or electric dipoles which are present, capable of being induced or introduced into neurological or neuromuscular tissue and are capable of being activated by an external alternating electromagnetic field. The cells in the neurological or neuromuscular tissue may consist of neurons (central or peripheral) and supporting cells i.e. glial cells, oligodendrocytes, etc. The activation of these magnetic or electric dipole particles allows modulation and control of neuronal and supporting cell activity.
