Annular Phased Array Hyperthermia System for Deep Brain Tumor Focusing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hyperthermia systems for treating cancer are limited in their ability to create small, deep focal zones in large tissue masses, such as the human torso, due to frequency constraints that prevent precise targeting of tumors, especially those smaller than 8 cm in diameter, and often result in excessive heating of surrounding normal tissue.
Innovation Solution
An annular phased array system operating at frequencies between 900 to 930 MHz, preferably 915 MHz, with a specific design that includes multiple antennas and a bolus media with a dielectric constant of 78, allowing for precise control of phase and amplitude to create a small, deep focal zone of about 3 cm or less, minimizing heating of normal tissue and avoiding hot spots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional hyperthermia systems operate at lower frequencies to penetrate deep tissue, then deep tissue heating is achieved, but the focal zone size becomes too large (greater than 8 cm) to precisely target small tumors
Solution Approach 1:
The patent changes the operating frequency parameter from conventional lower frequencies (e.g., 100-300 MHz) to higher frequencies (900-930 MHz, preferably 915 MHz). This parameter change enables the creation of a small deep focal zone (3 cm or less) while maintaining adequate penetration depth, resolving the contradiction between focal precision and deep tissue heating capability
Solution Approach 2:
The patent employs a phased array system with electronically controllable phase and amplitude for each antenna element. This dynamic control capability allows precise steering and focusing of the focal zone to small tumors deep within tissue, achieving both deep penetration and precise targeting without excessive heating of surrounding normal tissue
2Manufacturing precision
If the focal zone is made smaller to target precise tumor locations, then treatment precision improves, but the system requires higher frequencies that reduce penetration depth in large tissue masses
Solution Approach 1:
The patent selects a specific frequency range (900-930 MHz, preferably 915 MHz) that optimizes the balance between focal zone size and penetration depth. At this frequency, the wavelength in tissue is sufficient to penetrate deep into large tissue masses while enabling focal zones of 3 cm or less, simultaneously achieving both precise targeting and adequate penetration
Solution Approach 2:
The patent uses a three-dimensional phased array configuration with multiple antenna elements arranged in space. By controlling the phase and amplitude across this 3D array, the system can focus energy precisely at deep locations within tissue, achieving small focal zones at depth by utilizing spatial dimensionality rather than relying solely on frequency adjustments
3Length of stationary object
If conventional frequencies are used, then penetration depth is adequate, but the focal zone diameter exceeds 8 cm making it impossible to treat smaller tumors selectively
Solution Approach 1:
The patent changes the operating frequency to 900-930 MHz (preferably 915 MHz), which reduces the wavelength in tissue compared to conventional frequencies. This wavelength reduction enables the formation of smaller focal zones (3 cm or less in diameter) while maintaining adequate penetration depth into large tissue masses, allowing selective treatment of small tumors without treating surrounding normal tissue
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables selective heating of deep-seated tumors within the brain and other tissues, enhancing cancer treatment by increasing blood flow, oxygenation, and metabolic functions, while minimizing damage to surrounding healthy tissue.
Implementation Method 1
An array of electromagnetic radiator applicators is used to surround the body of an adult size tissue mass and operated at a frequency range of 900 to 930 MHz, or greater, with a currently preferred frequency being about 915 MHz
Implementation Method 2
The space between the antennas and the body is filled with the customary bolus having a bolus media therein. The bolus media has a dielectric constant which is that of water at approximately 78
Implementation Method 3
allowing for precise control of phase and amplitude to create a small, deep focal zone of about 3 cm or less
Data Source
AI summary
A radio frequency annular phased array hyperthermia system providing a heated focal zone with a diameter of 3 cm or less in a tissue mass includes a plurality of at least 42 radio frequency energy applicators in three rings adapted to surround the tissue mass. A bolus having a dielectric constant is positioned between the energy applicators and the tissue mass. The energy applicators operate at a frequency of at least about 900 MHz. to create the heated focal zone. The circumferential spacing between adjacent applicators in each ring is less than a critical distance and spacing between adjacent side by side rings is also less than a critical distance with such critical distances being interdependent on the frequency of the energy radiated, the dielectric constant of the bolus, the size of the bolus, and the size of the tissue mass.