Intravascular Ultrasound Line Density via Trigger Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current intravascular ultrasound (IVUS) systems face limitations in scan line density due to the constraints of rotary encoders, which restrict the resolution and accuracy in identifying delicate structures like vulnerable plaques within arteries, as they can only provide a limited number of trigger signals per rotation, leading to inadequate image quality.
Innovation Solution
The system employs a mechanical device to generate a set of trigger signals for each catheter revolution, allowing for the capture of multiple scan lines per trigger signal, thereby increasing scan line density and enabling high-resolution imaging by averaging adjacent lines and using different frequencies for harmonic imaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a rotary encoder with higher step density is used to increase scan line density, then image resolution is improved, but the electronics cannot faithfully detect each step due to limited detection capability
Solution Approach 1:
The patent divides the rotation detection function into two independent parts: a low-resolution rotary encoder provides coarse angular position (trigger signals), while a high-resolution position sensing system (optical or magnetic) provides fine angular position within each encoder step. This segmentation allows each subsystem to operate within its reliable detection range while achieving high overall precision.
Solution Approach 2:
The patent introduces an intermediary position sensing mechanism that operates between the rotary encoder and the ultrasound transducer triggering system. This intermediary system (optical or magnetic position sensor) detects the precise angular position within each encoder step, acting as a mediator that bridges the coarse encoder signals with the need for fine-grained scan line positioning.
2Measurement precision
If multiple scan lines are captured per trigger signal to increase density, then image quality is improved, but system complexity increases
Solution Approach 1:
The patent implements dynamic control of scan line capture, where the number of scan lines captured per trigger signal varies based on the specific imaging requirements and rotational position. The system can adaptively adjust the scan line density in different angular regions, capturing more lines where higher resolution is needed and fewer lines where standard density suffices, thereby managing complexity dynamically rather than statically.
Solution Approach 2:
The patent applies different scan line densities to different regions of the imaging field based on local requirements. High-density scan lines are captured in regions requiring fine detail (such as near the catheter tip), while lower-density lines are used in regions where coarser sampling is adequate, optimizing the balance between image quality and system complexity.
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 significantly enhances image resolution, improves signal-to-noise ratio, and allows for the discrimination of blood and tissue types, enabling the detection of fine structures within arteries, including vulnerable plaques, before they become symptomatic.
Implementation Method 1
an intravascular ultrasonic transducer to transmit and receive ultrasonic signals
Implementation Method 2
receive backscattered signals from the vessel
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The invention generally relates to intravascular ultrasound imaging and to systems and methods to improve line density and image quality. The invention provides an intravascular imaging system that uses a clock device to provide a set of trigger signals for each revolution of the imaging catheter and capture various patterns of scan lines for each set of trigger signals. The system can be operated to capture two scan lines of data for each trigger signal thereby doubling scan line density compared to existing systems. The clock device can be provided by hardware, such as a rotary encoder, that is configured to define a maximum number of trigger signals that the module can provide per rotation of the catheter.