CN111803179A - Self-screening type embolectomy support with strong capturing force - Google Patents
Self-screening type embolectomy support with strong capturing force Download PDFInfo
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- CN111803179A CN111803179A CN202010900937.XA CN202010900937A CN111803179A CN 111803179 A CN111803179 A CN 111803179A CN 202010900937 A CN202010900937 A CN 202010900937A CN 111803179 A CN111803179 A CN 111803179A
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- stent
- main body
- gathering
- bracket
- self
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/22—Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for
- A61B17/221—Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/22—Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for
- A61B17/221—Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions
- A61B2017/2212—Gripping devices in the form of loops or baskets for gripping calculi or similar types of obstructions having a closed distal end, e.g. a loop
Abstract
The invention discloses a self-screening thrombus removal bracket with strong capture force, which relates to the field of medical instruments and comprises a far-end gathering screen, an upper half bracket main body, a bracket middle section and a lower half bracket main body; the upper half bracket main body, the bracket middle section and the lower half bracket main body are all net-cylinder-shaped structures; the diameter of the section of the middle section of the bracket is smaller than the diameter of the sections of the upper half bracket main body and the lower half bracket main body; one end of the middle section of the bracket is connected with the upper half bracket main body; the other end of the middle section of the bracket is connected with the lower half bracket main body; the far-end gathering screen is arranged at the far end of the embolectomy support and is connected with the upper half support main body; the far-end gathering screen comprises a plurality of gathering flaps, and the gathering flaps are inwards retracted from the periphery. The invention has reasonable design and strong practicability, eliminates the risk of losing the thrombus in the process of pulling out the thrombus from the body, and increases the capability of capturing the thrombus.
Description
Technical Field
The invention relates to the field of medical instruments, in particular to a self-screening thrombus removal support with strong capture force.
Background
Cerebral apoplexy is one of the common diseases in the world at present, and has the characteristics that: high incidence/high prevalence/high disability rate. The annual incidence rate of urban cerebrovascular diseases in China is 219/10 ten thousand, the annual incidence rate in rural areas is 185/10 ten thousand, and the annual incidence rate is increased year by year. The prevalence of cerebrovascular disease has risen from 5.9% to 9.7% from 1998 to 2008. In patients with a viable cerebrovascular disease, about three-quarters of the patients have lost work capacity to varying degrees, and 80% of patients with stroke have reported varying degrees of limb dysfunction, with 43.7% of patients not able to take care of their lives. rt-PA thrombolytic by intravenous injection is the only current treatment method for acute phase cerebral infarction proven by evidence-based medicine. However, the intravenous thrombolytic therapy has long time, great damage to ischemic brain tissue and bleeding risk, and very low recanalization rate; the recanalization rate of basilar artery thrombolysis is only about 30%, the recanalization rate of lesion thrombolysis at the tail end of carotid artery is only 6%, and the recanalization rate of common carotid artery thrombolysis is only about 27%. And the time window for intravenous thrombolysis is only about 4 hours. From the above, the single use of venous thrombolysis for cerebral artery occlusion is far from sufficient, and the single use of venous thrombolysis may not be sufficient to meet the actual clinical requirements.
The thrombus removal system is used for removing thrombus in large intracranial blood vessels of patients with ischemic stroke so as to restore blood flow. During clinical operation, a guide catheter is placed according to a standard interventional operation method to obtain a vascular access, the position of vascular embolism is determined according to angiography, and then a microcatheter is guided to reach the position of vascular embolism; then the bracket part of the product is put into the guide sheath, then the product enters the micro catheter along the guide sheath, the thrombus taking device is slowly pushed to reach the thrombus position along the micro catheter, and then the micro catheter is carefully withdrawn to release the thrombus taking bracket; after waiting for several minutes, the micro-catheter and the thrombus taking device are simultaneously withdrawn by matching with the balloon catheter, the micro-catheter and the thrombus taking device are withdrawn into the guide catheter and then withdrawn out of the body, and the thrombus is taken out of the body.
The existing thrombus taking support has the problems of insufficient thrombus capturing capacity, thrombus falling off and the like easily in the thrombus taking process. During the expansion of the stent, the cut thrombus on the thrombus body can be washed to other parts by blood flow to cause lesion. The process of thrombus removal is time-consuming, the blood vessel recanalization rate is low, and if the process is long, the process can lead to long ischemia time and easily cause irreversible damage to the brain. If the thrombus taking support is not properly designed, irreversible damage is easily caused to the blood vessel, and other complications such as blood vessel rupture and the like are caused; the above are all the problems which the thrombus taking stent system must face for treating cerebral apoplexy caused by cerebral thrombosis.
Therefore, those skilled in the art are devoted to develop a self-screening thrombus extraction stent with strong capturing power, which adopts memory alloy, the far-end heat setting is a gathering sieve with inward split type around, and the middle-section heat setting is a thin waist type, the structural design enables the stent to have a three-dimensional structure, the risk of thrombus loss in the process of pulling out of the body is eliminated, and the capturing capability of the thrombus is increased.
Disclosure of Invention
In view of the above defects in the prior art, the technical problem to be solved by the invention is how to reasonably design, so that the grasping capability of the thrombus taking support on the thrombus is enhanced, and the risk of losing the thrombus in the process of pulling out the thrombus from the body is eliminated.
In order to achieve the aim, the invention provides a self-screening thrombus extraction support with strong capture force, which comprises a far-end gathering screen, an upper half support main body, a support middle section and a lower half support main body; the upper half bracket main body, the bracket middle section and the lower half bracket main body are all net-cylinder-shaped structures; the diameter of the section of the middle section of the bracket is smaller than the diameter of the sections of the upper half bracket main body and the lower half bracket main body; one end of the middle section of the bracket is connected with the upper half bracket main body; the other end of the middle section of the bracket is connected with the lower half bracket main body; the far-end gathering screen is arranged at the far end of the embolectomy support and is connected with the upper half support main body; the far-end gathering screen comprises a plurality of gathering flaps, and the gathering flaps are gathered inwards from the periphery.
Further, the stent is crimped into a thin bundle and can be restored to a mesh cylinder structure after release.
Further, the upper half support body and the lower half support body are provided with corrugated grids.
Furthermore, the middle section of the bracket is of a thin waist type three-dimensional structure provided with grids.
Further, the area of the corrugated mesh is larger than the area of the mesh.
Furthermore, a gathering valve grid is arranged on the gathering valve, and the area of the gathering valve grid is smaller than that of the grid.
Further, the radial direction of the upper half stent body and the lower half stent body is a closed loop structure.
Further, the number of the distal gathering screens is odd.
Further, the converging flap also comprises a vertical bar.
Further, the inner side of the gathering screen is gathered towards the upper half bracket main body.
Furthermore, the angle of the inner side of the gathering screen, which is closer to the upper half bracket main body, is more than 180 degrees.
Further, the outer side of the gathering screen is connected with the upper half bracket main body.
Further, the outer side of the gathering screen is welded with the upper half bracket main body.
Furthermore, the material of the embolectomy support is memory alloy.
Furthermore, the two ends of the middle section of the support are respectively connected with the upper half support body and the lower half support body through welding.
Compared with the prior art, the invention has the following advantages:
(1) the gathering screen and the middle section thin waist type design in the invention increase the gripping capability of emboli. After the stent is opened, when the stent passes through a bent lesion or a tiny lumen blood vessel, the far-end valve is designed to have a closing angle of more than 180 degrees, so that the closing valve cannot be opened by radial pressure, and the valve can be compacted on the contrary, and the phenomenon that emboli fall off in the process of withdrawing the stent from the body is effectively avoided.
(2) Compared with an open-loop stent, the stent gathering screen disclosed by the invention adopts an odd-number valve design, so that the opposite surfaces of the gathering valves cannot generate interference, the stent gathering screen is easy to form, the stent is not high in sensitivity to the diameter of a blood vessel, and the thickness of the blood vessel does not need to be judged before an operation to select a proper open-loop thrombus removal stent (the open-loop stent needs to form a laminated three-dimensional structure to increase thrombus removal capability). Meanwhile, when the stent passes through a thick blood vessel in the withdrawing process, the open-loop stent has the possibility of continuing expansion, so that the function of a laminated structure is weakened or disappeared, and the thrombus is lost in the process of pulling out the thrombus from the body. And the converging screen at the distal end of the stent completely eliminates this risk.
(3) The stent is designed in a radially closed loop mode, the supporting force and the opening uniformity are superior to those of an open loop design, particularly in a bent cerebral vessel, the opening capability and the uniformity are high, and meanwhile, the closed loop design cannot generate a sheet-shaped free end of a curled edge, so that the risk that the curled edge loses at the bent part of the blood vessel in the retracting process is avoided.
The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.
Drawings
FIG. 1 is a schematic view of a self-screening embolectomy holder with strong capture force, in accordance with a preferred embodiment of the present invention;
FIG. 2 is a distal end view of a self-screening embolectomy stent with strong capture force, in accordance with a preferred embodiment of the present invention;
FIG. 3 is a top view of a self-screening thrombectomy stent distal end gathering screen with strong capture force according to a preferred embodiment of the present invention;
FIG. 4 is a schematic illustration of a self-screening embolectomy stent body with strong capture force, in accordance with a preferred embodiment of the present invention;
FIG. 5 is a schematic illustration of a middle section of a self-screening embolectomy stent with strong capture force, in accordance with a preferred embodiment of the present invention;
FIG. 6 is a schematic diagram of a mid-section grid of a self-screening embolectomy stent with strong capture force, in accordance with a preferred embodiment of the present invention;
wherein: 1-distal end gathering screen, 2-upper half support body, 3-support middle section, 4-lower half support body, 5-gathering valve, 6-gathering valve inner side, 7-gathering valve outer side, 8-bending line, 9-gathering valve grid, 10-waveform grid, 11-grid and 12-vertical bar.
Detailed Description
The technical contents of the preferred embodiments of the present invention will be more clearly and easily understood by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.
In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.
As shown in fig. 1, 2 and 3, the invention provides a self-screening thrombus extraction support with strong capture force, which comprises a far-end gathering screen 1, an upper half support body 2, a support middle section 3 and a lower half support body 4. The stent is processed by memory alloy, has certain self-expansion capability after being subjected to heat setting, can be pressed and held into a thin bundle, and can be restored into a mesh tube structure after being released. The distal gathering screen 1 is composed of a plurality of gathering flaps 5. The gathering flaps 5 are structurally gathered inwards from the periphery, and each gathering flap 5 is composed of a plurality of gathering flap grids 9 and vertical bars 12. The inner side 6 of the gathering valve is gathered (bent line 8) towards the upper half bracket body 2, and the gathering angle is more than 180 degrees. The number of the gathering petals 5 is preferably odd petals, so that mutual interference of the opposite petals is avoided, and the gathering petals cannot be gathered for 180 degrees, and meanwhile, mutual interference of the opposite surfaces of the gathering petals 5 and radial pressure are avoided to open the gathering petals. The gathering valve outer side 7 is welded with the upper half bracket main body 2. Because the opposite surfaces of odd valves of the distal-end gathering screen 1 cannot generate interference, the distal-end gathering screen 1 of the stent is easy to form, the stent has low sensitivity to the diameter of a blood vessel, and the proper open-loop thrombus removal stent (the open-loop stent needs to form a laminated three-dimensional structure to increase thrombus removal capacity) is selected without judging the thickness of the blood vessel by radiography before operation. Meanwhile, when the stent passes through a thick blood vessel in the withdrawing process, the open-loop stent has the possibility of continuing expansion, so that the function of a laminated structure is weakened or disappeared, and the thrombus is lost in the process of pulling out the thrombus from the body. While the carrier's distal end gathers the screen 1 completely eliminates this risk.
As shown in fig. 4, the upper half stent body 2 is a single-layer closed loop structure, the mesh cylinder of the stent is composed of a plurality of wave-shaped meshes 10, and the area of the wave-shaped meshes 10 is larger than that of the meshes 9 of the gathering valve 5. The main net barrel is symmetrical left and right. The radial closed-loop design, the supporting force and the opening uniformity are superior to those of the open-loop design, particularly in the bent cerebral vessels, the opening capability and the uniformity are high, and meanwhile, the closed-loop design can not generate the sheet-shaped free end of the curled edge, so that the risk that the curled edge causes loss at the bent part of the blood vessel in the retraction process can not be caused.
As shown in fig. 5 and 6, the middle section 3 of the stent is heat-set in a thin waist form, the mesh cylinder of the middle section 3 of the stent is composed of meshes 11, and the area of the meshes 11 is larger than that of the gathered valve meshes 9 and smaller than that of the wave-shaped meshes 10. The tail end of the middle bracket section 3 is respectively welded with the upper half bracket body 2 and the lower half bracket body 4. The thin waist form of the middle section 3 of the bracket has a three-dimensional structure, so that the capturing capability of thrombus is improved.
The main using process of the thrombus removal device is as follows: in the blood vessel, free thrombus blocks the artery branch at the far end due to some reason, and a doctor pushes a micro-catheter to the near end of the artery blood vessel blocked by the thrombus and penetrates the thrombus in an interventional operation, and then moves an embolectomy device containing an embolectomy stent from the interior of the micro-catheter to the far end of the thrombus. The stent controls the distal bunching flaps 5 from bunching inward as it enters the introducer sheath. The thrombus taking stent is gradually released in a conical manner and expanded, and the thrombus is wrapped from the inside to the outside. When the micro catheter at the thrombus is withdrawn, the far-end gathering sieve 1 is firstly opened, the far-end gathering valve 5 is gathered into a mesh sieve on the section of the blood vessel after the micro catheter is opened, the grids 11 of the far-end gathering sieve 1 are dense, the thrombus main body and the broken thrombus can be effectively prevented from running out of the thrombus taking support, the purpose of completely taking out the thrombus is achieved, and finally the blood flow in the blood-carrying vessel is smooth after the thrombus is taken out.
The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.
Claims (10)
1. A self-screening thrombus removal support with strong capture force is characterized by comprising a far-end gathering screen, an upper half support main body, a support middle section and a lower half support main body; the upper half bracket main body, the bracket middle section and the lower half bracket main body are all net-cylinder-shaped structures; the diameter of the section of the middle section of the bracket is smaller than the diameter of the sections of the upper half bracket main body and the lower half bracket main body; one end of the middle section of the bracket is connected with the upper half bracket main body; the other end of the middle section of the bracket is connected with the lower half bracket main body; the upper half bracket main body and the lower half bracket main body are provided with corrugated grids, the middle section of the bracket is of a thin waist type three-dimensional structure provided with the grids, and the area of each corrugated grid is larger than that of each grid; the far-end gathering screen is arranged at the far end of the embolectomy support and is connected with the upper half support main body; the far-end gathering screen comprises a gathering valve, the gathering valve is gathered inwards from the periphery, a gathering valve grid is arranged on the gathering valve, the area of the gathering valve grid is smaller than that of the grid, and the plug taking support is made of memory alloy.
2. The self-screening embolic stent with high capture force of claim 1, wherein the radial direction of the upper stent body half and the lower stent body half is a closed loop structure.
3. The self-screening embolectomy stent of claim 1 having strong capture force wherein the petals are an odd number.
4. The self-screening embolectomy stent of claim 1 having strong capture force, wherein the converging flaps further comprise vertical bars.
5. The strong capture, self-screening embolic stent of claim 1, wherein the inner side of the distal gathering screen is gathered toward the upper stent body half.
6. The strong capture self-screening embolic stent of claim 5, wherein the angle of the inner lateral of the distal gathering screen that converges towards the upper stent body is above 180 degrees.
7. The strong capture, self-screening embolic stent of claim 5, wherein the outer side of the distal gathering screen is attached to the upper stent body half.
8. The strong capture self-screening embolic stent of claim 7, wherein the outside of the distal gathering screen is connected to the upper stent body half by welding.
9. The self-screening embolic stent with strong capture force of claim 1, wherein the stent is crimped into a thin bundle and is capable of returning to a mesh-barrel configuration after release.
10. The self-screening embolectomy stent with strong capturing force of claim 1, wherein both ends of the middle section of the stent are respectively connected with the upper half stent body and the lower half stent body by welding.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010900937.XA CN111803179B (en) | 2020-09-01 | 2020-09-01 | Self-screening type embolectomy support with strong capturing force |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010900937.XA CN111803179B (en) | 2020-09-01 | 2020-09-01 | Self-screening type embolectomy support with strong capturing force |
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| CN111803179A true CN111803179A (en) | 2020-10-23 |
| CN111803179B CN111803179B (en) | 2020-12-04 |
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Citations (6)
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| US6348056B1 (en) * | 1999-08-06 | 2002-02-19 | Scimed Life Systems, Inc. | Medical retrieval device with releasable retrieval basket |
| CN105476689A (en) * | 2015-12-28 | 2016-04-13 | 威海维心医疗设备有限公司 | Thrombus extraction support device |
| US20170086861A1 (en) * | 2015-09-28 | 2017-03-30 | Gyrus Acmi, Inc. D/B/A Olympus Surgical Technologies America | Stone collection device |
| CN107874811A (en) * | 2017-12-06 | 2018-04-06 | 北京久事神康医疗科技有限公司 | New cerebral thrombus withdrawing device and the method that bolt is taken using the device |
| CN109512486A (en) * | 2018-11-12 | 2019-03-26 | 中国人民解放军总医院 | Segmented takes bolt bracket |
| CN110575225A (en) * | 2018-06-07 | 2019-12-17 | 微创神通医疗科技（上海）有限公司 | Thrombectomy device and interventional medical system |
-
2020
- 2020-09-01 CN CN202010900937.XA patent/CN111803179B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6348056B1 (en) * | 1999-08-06 | 2002-02-19 | Scimed Life Systems, Inc. | Medical retrieval device with releasable retrieval basket |
| US20170086861A1 (en) * | 2015-09-28 | 2017-03-30 | Gyrus Acmi, Inc. D/B/A Olympus Surgical Technologies America | Stone collection device |
| CN105476689A (en) * | 2015-12-28 | 2016-04-13 | 威海维心医疗设备有限公司 | Thrombus extraction support device |
| CN107874811A (en) * | 2017-12-06 | 2018-04-06 | 北京久事神康医疗科技有限公司 | New cerebral thrombus withdrawing device and the method that bolt is taken using the device |
| CN110575225A (en) * | 2018-06-07 | 2019-12-17 | 微创神通医疗科技（上海）有限公司 | Thrombectomy device and interventional medical system |
| CN109512486A (en) * | 2018-11-12 | 2019-03-26 | 中国人民解放军总医院 | Segmented takes bolt bracket |
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| CN111803179B (en) | 2020-12-04 |
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Address after: 201201 Room 201, building 4, No. 590, Ruiqing Road, Zhangjiang High Tech Industry East District, Pudong New Area, Shanghai Patentee after: Shanghai Xinwei Medical Technology Co.,Ltd. Address before: 201201 Room 201, building 4, No. 590, Ruiqing Road, Zhangjiang High Tech Industry East District, Pudong New Area, Shanghai Patentee before: SHANGHAI XINWEI MEDICAL TECHNOLOGY Co.,Ltd. |
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