Preclinical success but clinical failure of the sutureless excimer laser-assisted non-occlusive anastomosis (SELANA) slide

The Sutureless Excimer Laser Anastomosis Clip Pilot Study: a feasibility and safety study

BACKGROUND

The excimer laser-assisted non-occlusive anastomosis (ELANA) bypass technique may have the advantage of its non-occlusive design in the treatment of last-resort cases where endovascular treatment or direct clipping is considered to be unsafe. However, the technique remains technically challenging. Therefore, a sutureless ELANA Clip device (SEcl) was developed to simplify the technique avoiding tedious anastomosis stitching in depth. The present study investigates the clinical feasibility and safety of the SEcl technique.

METHODS

Three patients with complex and large aneurysms in the anterior circulation were selected after multidisciplinary consensus that the aneurysms were too complex for endovascular or direct clipping treatment options. Bypass surgery was considered as a last-resort treatment option, and after preoperative evaluation and informed consent, SEcl bypass surgery was performed. Applicability, technical aspects and patient outcomes are assessed.

RESULTS

All aneurysms were excluded from the circulation. The creation of the intracranial anastomosis was easier and faster. No device-related serious adverse events were encountered, and all outcomes were favorable (one patient stable Modified Rankin Scale, two patients improved).

CONCLUSION

The SEcl anastomosis technique is feasible and, considering the severity of the disease, relatively safe. It can be considered a treatment option in very difficult-to treat last-resort aneurysm cases. From this study, further developments in minimizing clip size and application in cardiac surgery are initiated.

Evolution of Intracranial-Intracranial Bypass Surgery: A Bibliometric Analysis

OBJECTIVE

Modern cerebrovascular bypass surgery uses either extracranial-intracranial (EC-IC) or intracranial-intracranial (IC-IC) approaches. Compared with EC-IC bypasses, IC-IC bypasses allow neurosurgeons to safely address tumors, aneurysms, and other lesions using shorter grafts that are well matched to the size of recipient vessels. Fewer than 100 articles have been published on IC-IC bypasses compared with more than 1000 on EC-IC bypasses. This study examined the increase of interest and innovation in IC-IC bypass.

METHODS

PubMed and Web of Science were searched using keywords specific to IC-IC bypass, yielding 717 articles supplemented with 36 reports from other databases and gray literature. The articles were reviewed, and 98 articles were selected for further evaluation. Final articles were categorized as innovations or retrospective studies. Publication metrics were passed through an analytic program to assess statistical measures of growth.

RESULTS

The number of publications describing innovations (n = 52) and retrospective studies (n = 46) in IC-IC surgical techniques increased exponentially (R2 = 0.983 and R2 = 0.993, respectively), with both interest and research in the field increasing. The rate of publications in each group also increased. In recent years, increasing numbers of global institutions have researched and published on IC-IC bypasses.

CONCLUSIONS

As more work is undertaken on IC-IC bypasses, it is critical for knowledge to be shared through research, collaboration, publication, and early teaching within residency training programs. This field has increased exponentially in the past 2 decades and has yet to reach an inflection point, indicating possible additional interest and growth over time.

A systematic review of sutureless vascular anastomosis technologies

Vascular anastomoses typically involve a handsewn technique requiring significant surgical training, expertise, and time. The aim of our systematic review was to identify and describe sutureless vascular anastomosis techniques. We performed a systematic review of all sutureless vascular anastomosis technologies published in MEDLINE, PubMed, Embase, CINAHL, Cochrane, Web of Science, and Scopus Library databases and a patent review using US Patent and Trade Office Application, US Patent and Trademark Office Patent, Google Patents, Lens, Patent Quality Through Artificial Intelligence, SureChEMBL, and E-Space Net. Data from inclusion studies and patents published between January 1, 1980 and July 15, 2021 were abstracted to describe their category, anastomosis type and configuration, study types, and advantages and disadvantages encountered with each technology. Two hundred eleven original studies and 475 patents describing sutureless vascular anastomosis technologies were identified. In the literature, stents/stent-grafts/grafts (n = 61), lasers (n = 53), and couplers (n = 27) were the predominant device categories. In the patent review, adhesive technologies (n = 103), stents/stent-grafts/grafts (n = 68), and mechanical connectors (n = 61) predominated. The majority of studies involved in vivo animal studies (n = 193); 32.2% (n = 68) of investigations involved human trials; and 17.9% (n = 85) of patent technologies were approved by the US Food and Drug Administration. The main advantages described for sutureless anastomosis technologies included faster procedure time and greater patency rates compared with handsewn anastomoses. The main disadvantages included reduced vessel compliance, stenosis, leakage, and device costs. The appeal of sutureless technology is substantiated by numerous animal trials, but their use in humans remains limited. This may be a reflection of strict regulatory criteria and/or vascular complications associated with currently available technologies.

Long-term feasibility of the new sutureless excimer laser-assisted non-occlusive anastomosis clip in a pig model

BACKGROUND

High flow bypass surgery can be a last resort procedure for patients suffering from complex neurovascular pathology. Temporary occlusion of a recipient artery in these patients could result in debilitating neurological deficits. We developed a sutureless, mechanical anastomotic connection device, the SELANA clip (Sutureless Excimer Laser-Assisted Non-occlusive Anastomosis clip: SEcl). In the present study, we aim to determine the long-term non-inferiority of the SEcl technique compared with historical data of the conventional ELANA anastomosis technique.

METHODS

A total of 18 SEcl bypasses were created on the carotid artery in a porcine model in 6 different survival groups. Mean application times, flap retrieval rates, hemostasis, patency, flow, endothelialization, and remodeling were assessed.

RESULTS

The mean application time of the SEcl anastomoses was 15.2 ± 9.6 min, which was faster compared with the conventional ELANA anastomoses. The flap retrieval rate of the SEcl anastomoses was 86% (32/37). Direct hemostasis was achieved in 89% (33/37) SEcl anastomoses. Patency in all surviving animals was 94% (17/18). Bypass flow after six months was 156.5 ± 24.7 mL/min. Full endothelialization of the SEcl pins was observed after 3 weeks.

CONCLUSION

The SEcl technique is not inferior to the ELANA technique regarding patency, flap retrieval rate, flow, and endothelialization. On the basis of a significantly shorter application time and superior hemostasis, the SEcl technique could be preferable over the ELANA technique. A pilot study in patients is a logical next step based on our current results.

[Anatomical bases of brain revascularization: choosing an extra-intracranial bypass option]

Surgical brain revascularization is an important treatment for acute or chronic ischemia, intracranial aneurysms and skull base tumors. Individual anatomy of brain vessels should be clearly understood for this procedure. Variants of collateral cerebral blood flow in patients with cerebrovascular diseases depend on individual characteristics of circle of Willis and reserve mechanisms of collateral circulation. These anatomical variations require careful preoperative planning to choose the optimal revascularization option.

Technical Development of the Sutureless ELANA Clip Anastomosis Device

A cranial bypass can be a last resort procedure for patients suffering from complex neurovascular pathology. Since the clinically proven excimer laser-assisted nonocclusive anastomosis (ELANA) technique has become available, it is no longer necessary to temporarily close the recipient artery to facilitate an anastomosis. Aiming to simplify and shorten the operation time of the ELANA technique, a sutureless ELANA, the so-called SELANA slide (SEsl) was developed, but it failed during clinical study. We developed an improved device, the SELANA clip (SEcl).We describe the SEcl design and the first in vitro test results. The SEsl design was optimized with a clip at the backside, creating the SEcl which facilitates smooth and friction-free insertion in the recipient artery. Subsequently, the laser catheter was optimized by adding a grid and conus to provide an improved vacuum and flat reaction surface during lasing. We aimed to compare the SEcl to the current ELANA regarding application time difference, anastomosis success (“flap retrieval”) and technical difficulties. Hereto 32 ELANA and 32 SEcl anastomoses were performed on pressurized rabbit arteries in the ELANA practice system. Mean application time difference was 14.0 min (95%CI 13.0–15.0). The flap retrieval rate of the ELANA anastomoses was 94% (30/32) and 100% (32/32) for the SEcl technique. During the experiments no technical difficulties were encountered. The SEcl is technical feasible with promising simplicity and application times. However, extensive in vivo short-term and long-term experiments are indispensable before clinical application.

Feasibility of the new sutureless excimer laser-assisted non-occlusive anastomosis clip in a rabbit model

BACKGROUND

The excimer laser-assisted non-occlusive anastomosis (ELANA) technique facilitates the construction of anastomoses without temporary occlusion of the recipient artery. Experiments aimed at simplifying the technique eventually resulted in a sutureless ELANA slide (SEsl) anastomosis. After the first clinical use, new insights lead to the application of a clip at the back of the device, the SELANA clip (SEcl). The SEcl offers a distinct advantage over the SEsl since no sealant is necessary. In this study, we determine the feasibility of the SEcl anastomosis in an in vivo rabbit model.

METHODS

15 SEcl anastomoses and 15 conventional ELANA anastomoses were created on the abdominal aorta in 5 rabbits. Mean application times, flap retrieval rates, hemostasis, and burst pressures were assessed.

RESULTS

The mean application time of the SEcl anastomoses was 11.4 min versus 39.0 min for the ELANA anastomoses (mean difference, 27.6 min; 95% CI, 20.6-34.7). The flap retrieval rate of the SEcl anastomoses (14/15) was not inferior to the flap retrieval rate of the ELANA anastomoses (13/15). Direct hemostasis was achieved in 13/15 (87%) SEcl anastomoses and in 14/15 (94%) ELANA anastomoses. All SEcl anastomoses were resistant to provoked pressures until 250 mmHg.

CONCLUSION

The SEcl anastomosis is technically feasible in in vivo experiments. Mean application time, flap retrieval rate, hemostasis, and burst pressure are not inferior to the conventional ELANA anastomosis. Further long term experiments should be performed to assess safety, patency, and reendothelialization.