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Ryuzaburo Kanazawa1, Takanori Uchida1, Tetsuhiro Higashida1, Takao Kono1, Hiroki Ebise1, Noboru Kuniyoshi2
  1. Department of Neurosurgery, Nagareyama Central Hospital, Chiba, Japan
  2. Department of General Internal Medicine, Nagareyama Central Hospital, Chiba, Japan

Correspondence Address:
Ryuzaburo Kanazawa, Department of Neurosurgery, Nagareyama Central Hospital, Chiba, Japan.

DOI:10.25259/SNI_513_2024

Copyright: © 2024 Surgical Neurology International This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, transform, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: Ryuzaburo Kanazawa1, Takanori Uchida1, Tetsuhiro Higashida1, Takao Kono1, Hiroki Ebise1, Noboru Kuniyoshi2. A rescue treatment to release the twist of a flow re-direction endoluminal device. 09-Aug-2024;15:278

How to cite this URL: Ryuzaburo Kanazawa1, Takanori Uchida1, Tetsuhiro Higashida1, Takao Kono1, Hiroki Ebise1, Noboru Kuniyoshi2. A rescue treatment to release the twist of a flow re-direction endoluminal device. 09-Aug-2024;15:278. Available from: https://surgicalneurologyint.com/surgicalint-articles/13032/

Date of Submission
27-Jun-2024

Date of Acceptance
19-Jul-2024

Date of Web Publication
09-Aug-2024

Abstract

Background: A flow redirection endoluminal device (FRED) is a widely used flow diverter stent. Although high technical success and good treatment results were reported in the SAFE study, cases of technical failure of deployment have also been reported. A case in which a FRED was deployed with the proximal part twisted, but successful deployment was achieved, is presented.

Case Description: A woman in her 40s was diagnosed with a left internal carotid artery aneurysm during radiological investigations for headaches. Due to her family’s strong history of cerebral aneurysms, she opted for preventive treatment. A 5.5-mm FRED was selected because the proximal vessel diameter was ≥5 mm. However, the stent was deployed with the proximal side twisted. Fortunately, using a Scepter C and a CHIKAI 315 cm, the true lumen could be secure, the wire was guided distally, and the FRED was successfully placed. Later, with the patient’s consent, a 3D blood vessel model was created, and whether the stent was difficult to open or whether it was just a technical problem which was verified experimentally. Precisely, the same situation as during the surgery was recreated, and the stent was deployed in the same way.

Conclusion: A FRED is an effective device, but there are cases of difficult deployment. The present method may be an option if a FRED is difficult to open.

Keywords: Cerebral aneurysm, Flow redirection endoluminal device, Twist

INTRODUCTION

A flow redirection endoluminal device (FRED; Microvention-Terumo, Tustin, CA, USA) is a widely used flow diverter (FD) stent. A high technical success rate and good treatment outcomes were reported in the SAFE study,[ 8 , 9 ] and long-term outcomes were similar.[ 4 ] On the other hand, a few technical failures have been reported, with 5 cases (4.9%) reported in the SAFE study, of which three cases showed poor proximal expansion, one case had slow flow, and one case had stent migration. Although not stated, these situations were successfully recovered in all five cases: two cases using another FD, one case underwent stent-assisted coiling, and two cases received no treatment.[ 9 ] In addition, 2 cases (2.2%) underwent re-treatment, both of which were additions of an FD stent due to shortening.[ 8 ]

This paper describes a case in which the proximal side of a FRED was deployed without opening, and it was, fortunately, possible to successfully place it using a balloon catheter; however, whether the difficulty was due to our lack of technical skill or whether it was a case of difficult FRED deployment which was unclear. Therefore, a deployment experiment was conducted using a 3D aneurysm model, with the patient’s consent, to confirm whether precisely the same phenomenon that occurred during the procedure could be repeated. The experiment confirmed the same situation. Later, in a case in which it was assumed that a FRED would be difficult to deploy preoperatively, and the proximal side was deployed with insufficient expansion, the FRED was successfully placed. This method to deal with poor proximal expansion that may occur during FRED placement is reported.

Written informed consent for publication of this case report was obtained from each patient. The ethics committee of our institution approved this study on January 16, 2024, and the study followed the principles outlined in the Declaration of Helsinki.

CASE DESCRIPTION

A woman in her 40s presented with a left internal carotid artery aneurysm. The aneurysm was larger than 5 mm in her left siphon area. Given her strong family history of cerebral aneurysms, the patient’s preference was for preventive treatment. After obtaining the patient’s informed consent, she was started on aspirin 100 mg and clopidogrel 75 mg 2 weeks before surgery, and it was confirmed that there were no problems with platelet aggregation. The surgery was performed under general anesthesia. The guiding catheter was a 7-F Shuttle Sheath (Cook Medical, Bloomington, IN, USA) and a 5-F Sofia (MicroVention-Terumo), a Headway 27 (MicroVentionTerumo) was guided to the proximal part of the left middle cerebral artery (M1) using a CHIKAI black 18 (Asahi Intec, Aichi, Japan), and a FRED 5.5 mm × 22 mm was selected. Deployment was started midway through C2, but the stent would not open from C3, and re-sheathing and re-placing it was attempted several times [ Figure 1 ]. During this period, the tip wire tended to stray into the anterior choroidal artery (ACA), and the motor-evoked potential decreased, so the procedure was abandoned, and the treatment was repeated with the same device 1 week later. After the first session, she developed mild right paralysis and motor aphasia, which disappeared within half a day. To prevent the wire from entering into the ACA, deployment was started slightly more distally than the previous attempt, but the situation was the same. After several trials, the stent was deployed by mistake. When the stent was released from the Sofia by gently pushing it out, the proximal side was slightly open, so the CHIKAI 315 cm (Asahi Intec, Aichi, Japan) was carefully advanced from the Headway 27, and the true lumen was captured. Proceeding slowly, it was possible to secure the distal end. At this point, an exchange to a Scepter C (Microvention-Terumo) was performed, and the stent was fixed, which allowed stent placement in a good position [ Figure 2 ]. The patient had no neurological problems, and the postoperative radiological examinations did not show any shortening of the stent. She was discharged neurologically intact.


Figure 1:

First session. (a) 5-F Sofia to C4-5 portion and Headway 27 to M1 (bold arrow). (b) Although the flow re-direction endoluminal device is being deployed from the middle of C2, the tip of the delivery wire tends to stray into the anterior choroidal artery (arrow). (c) The stent is not opening from C3 (arrows).

 

Figure 2:

Second session. Intraoperative findings. (a) Working angle. (b) The FRED is not opening at all from the C3 section and is left within the Sofia (arrow). (c) After the FRED is released from the Sofia, the proximal end opens slightly (arrow). (d) As the CHIKAI 315 cm is used, the tip becomes J-shaped, and the true lumen can be secured (arrow). (e) Appropriate stent shortening and expanding when the wire secures the distal end of the stent. (f) The lumen of the stent is fixed using a Scepter. (g, h) Digital subtraction angiography after stent placement.

 

Experiment

After obtaining the patient’s consent, a 3D model of the area around the aneurysm was created, and an experiment using a similar system was conducted. The stent still failed to open from the same site, and after several attempts to confirm that the stent was difficult to place, the stent was decisively detached. When deployed, the proximal side opened slightly, and when the CHIKAI 315 cm was guided there, the tip immediately became J-shaped, and with the support of the microcatheter, the wire was advanced, and the distal end was secured. The stent was expanded and fixed using a Scepter C, as in the real procedure [ Figure 3 ]. In the real procedure and the experiment, it was confirmed that the distal part of the stent was anchored and stable in the designated position, the proximal end was slightly opened after deployment, which enabled to secure the true lumen of the stent. The twist was gradually released and only the proximal site of the stent as the wire advancing inside the lumen.


Figure 3:

The fluoroimages of the experiment. (a) The stent being difficult to open in the proximal part. (black arrows) (b) The proximal end being opened (white arrows) to be possible to capture the true lumen with the microwire (CHIKAI 315cm), which the tip smoothly becoming J shaped (bold black arrow) and (c) advancing inside the stent lumen (bold black arrow). (d) The stent twisting gradually released during the wire getting through (white arrows). (e) The fixing of the stent with balloon inflation and (f) after the deployment. The shortening of the stent being apparent in the proximal part not but the distal part, which resulted in successful placement in designated position without stent migration.

 

DISCUSSION

Pierot et al. reported that the FRED technical success rate in the SAFE study was 95% (98/103). Adequate occlusion 1 year after treatment was seen in 81.2% (73/90), and thromboembolic events (TEs) occurred in 4.9% (5/103): 3 during surgery, 2 on the next day, and 4 days later. One case (1%) of delayed rupture was reported.[ 8 , 9 ] Hohenstatt et al. reported adequate occlusion in 100% (53/53) at 5-year follow-up,[ 4 ] and Möhlenbruch et al. also reported adequate occlusion in 100% (30/30).[ 6 ] Both also reported on TEs, but in both cases, the symptoms were often mild, and the overall results were good.

However, a small number of technical failures have been reported. Pierot et al. reported technical failures in 4.9% (5/103).[ 8 , 9 ] Of the five cases, three had poor proximal expansion, one case had slow flow, and one case had stent migration. These five cases well represent the characteristics of FREDs and poor proximal expansion has been reported by Beppu et al., Suyama et al., and Johnson et al.,[ 2 , 5 , 10 ] and slow flow has been reported by Hirai et al.[ 3 ] Migration was thought to be a phenomenon caused by undersize.[ 8 ]

Beppu et al. reported that slow flow occurred 5 min after placement, and the cause was the deflection of the inner layer of the FRED. This situation was overcome by adding an Enterprise (CERENOVUS, Irvine, California, USA). The authors suggested that the cause was excessive pushing of the system.[ 2 ] Hirai et al. reported two cases of slow flow and attributed it to twisting of the inner layer at the proximal end of the stent.[ 3 ] They called it “ghost twisting” because the twisting was not visualized on the fluorogram. Suyama et al. reported poor deployment in 7.9% (3/39) of cases and changed the procedure to a pipeline (Medtronic Neurovascular, Irvine, CA, USA) in two cases.[ 10 ] Vessel tortuosity is considered to be the cause of FRED deployment failure, and it is not suitable for using a size that is 1 or 2 mm larger than the distal diameter of the target vessel or for S-shaped vessels, and a push and pull system, such as pipeline, is not suitable for FRED deployment. The authors concluded that FRED application under such situations is not beneficial.[ 10 ] Johnson et al. reported a case in which proximal twisting was detected after FRED placement, and the stent was retrieved using a Goose Neck Snare (GNS, Medtronic Neurovascular, Irvine, CA, USA).[ 5 ] They stated that they attempted to enter the true lumen with a Synchro-2 (Stryker, Kalamazoo, MI, USA) before the GNS recruitment, but the trial was unsuccessful. Morita et al. found that placement was difficult in 16.1% (5/31) of cases, and they suggested that FRED deployment was difficult when the siphon opening was <30° and the C4–5 portion was <90°.[ 7 ] Bender et al. reported on pipeline 999 placement, and in 2.5% (25/999) of cases, stent twists occurred, but most twists were released, except for only 2 cases (0.2%). According to the authors’ report, it is important to push and pull the system to let the twist gradually move proximally.[ 1 ]

From the above, a “twist” can be cited as a cause of FD deployment failure, but a FRED has a dual layer structure, and it is considered dangerous to perform excessive system push and pull, such as with a pipeline.[ 3 , 10 ] One option is to avoid using a FRED in cases where failure to expand is expected, as in the report by Suyama et al.,[ 10 ] but it is conceivable that it does not open contrary to expectation in real procedure as in the current case. In such cases, the present method may serve as a means of rescue. Johnson et al. stated that they were unable to secure the true lumen of a twisted FRED using Synchro-2.[ 5 ] The same situation occurred in the current procedure, but with the exchange to a CHIKAI 315 cm, the tip became naturally J-shaped and was able to pass through. A CHIKAI 315 cm is a guidewire for the exchange technique, and the tip is more flexible than a regular micro guidewire. Therefore, it is possible that the wire could be passed through the lumen without damaging it and the wire tip getting caught in the strut. This was confirmed experimentally, and stent deployment was possible with reproducibility in the second case, as well.

Regarding whether the proximal deployment failure of FRED is due to “twisting,” as shown in Figures 2b and 3b, the proximal side was opened, but the poor deployment was concentrated in one place, and in both the actual procedure and experimental one, the distal side is promptly opened and anchored, and when the balloon expands the stent, the distal site is hardly shortened, and the proximal is shortened. Therefore, the cause of the poor deployment of FRED may be that its radial force is relatively strong, and it is easy to open at first, but in vessels with tortuosity, the distal part is anchored, and the “twist” may be concentrated in one place. This point is thought to be the reason why there are slightly more reports of poor deployment in FRED than pipeline. It is difficult to release this “twist,” and since it is a dual layer structure, careless manipulation may damage the stent. In such a situation, it may be appropriate to retrieve the stent as Johnson et al. mentioned[ 5 ] or detach it as in the current case and secure the true lumen later. Although this is a conjecture from a single case and remains mere speculation, it might be one valid interpretation of the poor deployment of FRED.

However, there is a possibility that the wire may not enter the true lumen after the stent has been deployed, or even if it does, it may not be able to pass through the true lumen distally, so it is dangerous to think that this method is always possible. It was thought that it would be useful to know about this method as an option to remedy the situation in which FRED deployment was difficult.

CONCLUSION

Although FRED is an effective FD stent, poor proximal deployment sometimes occurs. To prevent this from happening, it is important to avoid arteries inappropriate for FREDs. In addition, if operators encounter deployment difficulties during actual deployment, they can either collect them without unnecessary push or pull (unlike pipeline, FRED can be re-collected into the introducer sheath) or deploy with a simple pull to avoid FRED damage. In some cases, it may be possible to secure the true lumen and reach the distal end with a micro guidewire later, in which case the CHIKAI 315 cm may be easier to pass than a regular micro guidewire.

Ethical approval

The research/study was approved by the Institutional Review Board at the Ethics Committee of Nagareyama Central Hospital, number NCH2024-8, dated January 16, 2024.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Disclaimer

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.

References

1. Bender MT, Young RW, Zarrin DA, Campos JK, Caplan JM, Huang J. Twisting: Incidence and risk factors of an intraprocedural challenge associated with pipeline flow diversion of cerebral aneurysms. Neurosurgery. 2020. 88: 25-35

2. Beppu M, Kuramoto Y, Abe S, Namitome S, Yoshimura S. Localized kinking during deployment of a flow redirection lumen device (FRED) could be due to excessive pushing. Surg Neurol Int. 2022. 13: 22

3. Hirai S, Ishikawa M, Sagawa H, Aoyama J, Fujita K, Fujii S. Ghost twisting of the dual-layer flow-diverting stent. Neuroradiology. 2023. 65: 1669-72

4. Hohenstatt S, Ulfert C, Herweh C, Hilgenfeld T, Schmitt N, Schönenberger S. Long-term follow-up after aneurysm treatment with the flow redirection endoluminal device (FRED) flow diverter. Clin Neuroradiol. 2024. 34: 181-8

5. Johnson R, Young M, Farhat H. Microsnare retrieval of a distorted flow re-direction endoluminal device (FRED). Cureus. 2021. 13: e19803

6. Möhlenbruch MA, Herweh C, Jestaedt L, Stampfl S, Schönenberger S, Ringleb PA. The FRED flow-diverter stent for intracranial aneurysms: Clinical study to assess safety and efficacy. AJNR Am J Neuroradiol. 2015. 36: 1155-61

7. Morita H, Kazekawa K, Tashiro N, Kawano H, Aikawa H. Predicting difficulty in flow re-direction endoluminal device (FRED) deployment using angiography: A technical note. Neurosci Infor. 2022. 2: 100073

8. Pierot L, Spelle L, Berge J, Januel AC, Herbreteau D, Aggour M. SAFE study (Safety and efficacy analysis of FRED embolic device in aneurysm treatment): 1-year clinical and anatomical results. J Neurointerv Surg 2019;. 11: 184-9

9. Pierot L, Spelle L, Berge J, Januel AC, Herbreteau D, Aggour M. Feasibility, complications, morbidity, and mortality results at 6 months for aneurysm treatment with the flow re-direction endoluminal device: Report of SAFE study. J Neurointerv Surg. 2018. 10: 765-70

10. Suyama K, Nakahara I, Matsumoto S, Suyama Y, Morioka J, Hasebe A. Efficacy of the flow re-direction endoluminal device for cerebral aneurysms and causes of failed deployment. Neuroradiology. 2022. 64: 1213-9

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