Eccentric Ultrasonic Probe Head With Flexible Sheath
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ultrasonic surgical tools with blunt straight probes are less effective in removing hard eschar buildup during wound healing and have limited energy transmission due to small diameter tips, leading to extended procedure times and operator fatigue.
Innovation Solution
An ultrasonic surgical instrument assembly with a rigid probe shaft, an eccentrically extending probe head, and a partially flexible sheath that allows the probe head to pivot and protrude through an aperture for enhanced tissue contact and energy delivery, featuring a knurled operative tip for effective bone ablation and irrigation/suction capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a blunt straight probe is used for ultrasonic ablation, then the device structure is simple and easy to manufacture, but it is less effective in removing hard eschar buildup and has limited energy transmission
Solution Approach 1:
The probe head is designed with an asymmetric configuration where the ultrasonic tip extends eccentrically beyond the sheath at an angle rather than straight ahead. This asymmetric positioning allows the tip to engage hard eschar more effectively while the sheath protects surrounding tissues, resolving the contradiction between structural simplicity and surgical effectiveness
Solution Approach 2:
The probe incorporates a flexible section that allows dynamic adjustment of the tip's protrusion distance from the sheath. This dynamic capability enables the tip to adapt its position for optimal energy transmission and tissue engagement, improving productivity while maintaining a relatively simple overall structure
2Ease of operation
If a small diameter cannulated tip is used, then the device is compact and easy to maneuver, but the annular area for energy transmission is limited
Solution Approach 1:
The ultrasonic tip is positioned to extend laterally beyond the sheath in a transverse direction rather than along the longitudinal axis. This dimensional change creates a larger effective working area perpendicular to the sheath axis, increasing energy transmission capacity without compromising the compact, maneuverable design provided by the small diameter sheath
3Productivity
If the probe head protrudes further from the sheath, then energy transmission and tissue contact are improved, but the risk of contacting non-target tissues increases
Solution Approach 1:
The sheath is designed with differentiated properties: the distal portion is flexible to allow tip protrusion and adaptation, while the proximal portion remains rigid to provide structural support and protection. This local quality differentiation enables the tip to extend for improved energy transmission while the rigid proximal sheath maintains control and reduces risk to non-target tissues
Solution Approach 2:
The sheath acts as an intermediary protective structure that allows the ultrasonic tip to extend beyond it for effective tissue contact while simultaneously shielding surrounding non-target tissues from direct exposure. The sheath mediates between the need for tip protrusion and the need to protect adjacent structures
4Stability of the object's composition
If a rigid sheath is used, then structural stability and protection are improved, but the ability to adapt to tissue contours and allow increased protrusion is reduced
Solution Approach 1:
The sheath incorporates a flexible section that transitions the structure from rigid to compliant in the distal region. This dynamic property allows the distal end to deflect and adapt to tissue contours while the proximal rigid portion maintains overall structural stability, resolving the contradiction between stability and adaptability
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
The design enables improved removal of hard tissues like bone with reduced procedure time and operator fatigue, enhancing safety and efficiency by allowing increased energy transmission and adaptive protrusion of the probe head for effective tissue ablation.
Implementation Method 1
The probe or tube is excited by a transducer of either the piezoelectric or magnetostrictive type that transforms an alternating electrical signal within the frequencies indicated into a longitudinal or transverse vibration.
Implementation Method 2
The probe or tube is excited by a transducer of either the piezoelectric or magnetostrictive type that transforms an alternating electrical signal within the frequencies indicated into a longitudinal or transverse vibration.
Implementation Method 3
Such devices ablate tissue by either producing cavitation bubbles which implode and disrupt cells, tissue compression and relaxation stresses (sometimes called the jackhammer effect) or by other forces such as micro streaming of bubbles in the tissue matrix.
Implementation Method 4
Such devices ablate tissue by either producing cavitation bubbles which implode and disrupt cells, tissue compression and relaxation stresses (sometimes called the jackhammer effect) or by other forces such as micro streaming of bubbles in the tissue matrix.
Data Source
Figure 1~3
Figure 4~6
Figure 7~8
AI summary
An ultrasonic surgical instrument assembly has a base, a rigid probe shaft coupled at a proximal end to the base, a probe head at a distal end of the shaft, and a sheath having a rigid distal end portion surrounding the shaft. The shaft has a longitudinal axis and is operatively connectable to a source of ultrasonic vibrational energy. The head extends eccentrically in a transverse direction to one side of the shaft, the head having an operative tip or surface spaced laterally from the axis. The distal end portion of the sheath is provided in a side wall with an aperture, and the probe head is aligned with the aperture. The sheath is coupled at a proximal end to the base and is provided with a partially flexible section between the distal end portion of the sheath and the instrument assembly base, so that the distal end portion is pivotably deflectable transversely to the axis in response to a lateral force applied to the distal end portion, to enable an increased protrusion of the head through the aperture.