Multi-Energy Direct Conversion Digital Mammography

US 10,018,738 B2, US 10,338,237 B2

GEKA Associates targets development and manufacturing of the flat-panel, multi-energy, photon counting ionization radiation sensor arrays for medical, industrial and security applications. Patented GEKA technology based on an inductive (RF) detection of the charge carriers generated by X-ray is offering superior energy resolution and sensitivity. Considering current market trends the initial target of GEKA development is specifically focused on the mammography.

The GEKA Beginning

Selenium-Based Digital Mammography - 1985


Technology
Inductive High-energy Radiation Detectors

Inductive radiation sensing technology based on a low-cost non-crystalline material offers a substantial increase of energy resolution and sensitivity as compared to conventional, photo-conductive detectors based on the crystalline materials. A preliminary evaluation performed using a high defect density segment of a CZT wafer indicated that sensitivity of the inductive radiation sensors based on the non-crystalline materials will increase by at least one order of magnitude as compared to sensors based the crystalline materials. It is projected that additionally to higher energy resolution, higher sensitivity and decreased cost of imaging detectors, use of non-crystalline materials would also offer greater flexibility in the construction of x-ray and gamma-ray imaging detectors, an improvement of their spatial resolution and detector size. Energy Resolution in commonly used photo-conductive radiation detectors (pcRD) the radiation produced charge carriers are collected at the electrodes at preset time intervals. Therefore, delays in the charge collection time due to carrier mobility and charge trapping at crystal defects affect height of the peaks and reduce energy resolution of detectors. Unlike pcRD detectors, detectors based on the inductive radiation (iRD) technology are sensing X-rays produced charges at the location where they are created in the sensor bulk with signal propagating at the speed of light and therefore not limited by the carrier mobility and charge trapping.
Patents: US 10,018,738 B2, US 10,338,237 B2

The GOAL

Flat-Panel Multi-Energy Mammography

MOTIVATION: According to the Breastcancer.org, 1 out of 8 women in the developed countries are expected to develop breast cancer in their lifetime. It has been estimated that 252,710 new cases of invasive breast cancer and 63,410 new cases of noninvasive breast cancer have been diagnosed by the end of 2017 in the U.S. [1] However existing mammogram technologies do not allow to detect breast cancer in the early enough stage, especially in women under the age of 50, to allow for more effective treatment of cancer in its early stage of development.

All mammograms utilize x-ray technology and dense tissue “blocks” x-rays. This means that tumors can be hidden by overlying dense tissue. The effect of breast density on a mammogram leads to reduced overall diagnostic accuracy in women under the age of 50, women with radiologically dense breasts, especially premenopausal and perimenopausal. [2] Standard mammography has been estimated to miss about 50% of cancers present in women with dense breasts. [3] The miss rate has not yet been fully established but remains an issue in dense breasts. [3]

Growing incidence of breast cancer is anticipated to be the primary factor responsible for driving growth of the mammography market. The increasing incidence and prevalence of breast cancer is expected to create high demand for early detection techniques. [1] Fulfilling this demand requires development of technologies allowing for early detection of the cancer and lowering cost of cancer screening itself. The current market trends indicate that photon-counting, multi-energy technologies offer the best solution for these requirements. GEKA Associates developed new X-ray photon counting technology (US 10,018,738 B2, US 10,338,237 B2) that offers new approach to detection of the ionizing radiation and specifically to X-rays used in mammography. The GEKA technology offers substantially higher sensitivity and energy resolution at dramatically lower cost than existing photon-counting technologies. This new technology, inductive detection of ionizing radiation, was demonstrated and is currently used in evaluation of materials used in detection of X-rays and Gamma-rays.

Market Projections: The global mammography market size was valued at USD 1.43 billion in 2015 and is projected to grow at a CAGR of 10.5% reaching about USD 4 billion in 2025. The advanced X-ray mammography (photon-counting, multi-energy X-ray) segment is projected to grow from 15% to 20% of the total mammography market over the next 7 years. The market is experiencing growth due to rising breast cancer cases and growing awareness pertaining to preventive checkup for breast cancer.[1] However these projections do not include possibility of a substantial improvement of the X-ray detection technology increasing diagnostic accuracy and reducing price of the advanced systems. GEKA addresses this deficiency by offering a new photon-counting, multi-energy X-ray detection technology that will allow to expand utilization of the advance mammography systems, increasing their market share by increasing diagnostic accuracy and lowering cost of the systems. GEKA intends to focus on manufacturing and sale of the X-ray research system to the biomedical research centers followed by sales of the X-ray detection subsystem to the mammography equipment manufacturers.

[1] Mammography market analysis and segment forecasts to 2025 (Grand View Research, Inc., USA) [https://www.grandviewresearch.com/industry-analysis/mammography-market].
[2] ClinicalTriala.gov number. NCT00008346.
[3] 3D Mammography, Tomosynthesis, Diagnostic Mammogram | DenseBreast-info [http://densebreast-info.org/breast-mammography-tomosynthesis.aspx? gclid=EAIaIQobChMImdqN29Dd3AIVRySGCh0j1A1BEAAYAiAAEg InpvD_BwE]

In comparison to currently available technologies, the inductive RF method dramatically improves energy resolution of radiation detectors independently of the crystal quality. It results in the improved isotopes differentiation which is critical in industrial, security and medical applications. It allows replacement of currently used expensive high-quality crystals with polycrystalline and non-crystalline materials. The sensitivity of the inductive radiation sensing actually increases with the increasing defect density.

Pixelated Radiation Detector
Based on non-crystalline semiconductors
Initial target materials: poly-crystalline CZT, amorphous-Se
Both materials are available in mass production at relatively low cost

Unlike detectors based on the photoconductive principle, inductive radiation sensing technology detects radiation generated charge carriers at the location where they are created and does not require high carrier mobility, low defect density materials and does not require high voltage biasing. Performance of inductive detectors even improves with increasing density of the defects. Therefore the use of polycrystalline materials, additionally to reducing cost of detectors, results in a substantial increase of the readout sensitivity and energy resolution as compared to detectors based on low defect density monocrystalline materials such as high resistivity CdZnTe (CZT). Improved energy resolution of radiation detectors results in an improved isotopes differentiation which is critical in industrial, security and medical applications.