Article Text

Original research
Endovascular treatment of wide-necked intracranial aneurysms using the Nautilus Intrasaccular System: initial case series of 41 patients at a single center
  1. Alexander Sirakov1,
  2. Pervinder Bhogal2,
  3. Kristina Sirakova3,
  4. Marin Penkov1,
  5. Krasimir Minkin4,
  6. Kristian Ninov4,
  7. Hristo Hristov4,
  8. Asen Hadzhiyanev4,
  9. Vasil Karakostov4,
  10. Stanimir Sirakov1
  1. 1 Radiology Department, University Hospital St Ivan Rilski, Sofia, Bulgaria
  2. 2 Interventional Neuroradiology, The Royal Hospital, London, UK
  3. 3 Radiology Department, University Hospital Alexandrovska, Sofia, Bulgaria
  4. 4 Neurosurgery Department, University Hospital St Ivan Rilski, Sofia, Bulgaria
  1. Correspondence to Dr Stanimir Sirakov, Radiology Department, University Hospital St Ivan Rilski, Sofia, Bulgaria; ssirakov{at}


Background Endovascular treatment of intracranial wide-necked and bifurcation aneurysms (WNBA) is technically challenging. The Nautilus Intrasaccular System is designed to provide a mechanical barrier at the aneurysm neck to support coil embolization. We report the results of a single-center series of patients treated for intracranial aneurysms with the Nautilus.

Methods Clinical and radiological data were retrospectively collected for all patients treated with the Nautilus for an unruptured or ruptured intracranial aneurysm at our center between March 2021 and March 2022. Clinical outcomes (modified Rankin Scale (mRS) scores), Raymond–Roy angiographic occlusion, recanalization, and complications were measured immediately post-procedure and at 3–6-month follow-up.

Results A total of 41 patients of mean age 56.7 years (range 37–83 years) were treated with the Nautilus, with 41 saccular aneurysms (18 (43.9%) unruptured and 23 (56.1%) ruptured). The majority of aneurysms (39/41 (95.1%)) were located in the anterior circulation. We experienced no technical complications. One patient had an asymptomatic post-procedural minor stroke related to the procedure. Immediate Class I occlusion was achieved in 30 (73.1%) patients. The rate of all-cause mortality was 7.3% (3/41). One patient was lost to follow-up. At follow-up, 94.5% (35/37) of patients achieved Class I occlusion and 94.5% (35/37) had an mRS score of 0. There were no procedural-related deaths or permanent morbidities at discharge or follow-up.

Conclusion This study demonstrates good safety and effectiveness using the Nautilus Intrasaccular System to treat both ruptured and unruptured intracranial aneurysms. Larger studies are needed to confirm these findings.

  • Aneurysm
  • Angiography
  • Artery
  • Brain

Data availability statement

Data are available upon reasonable request.

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Data availability statement

Data are available upon reasonable request.

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  • Contributors All authors contributed to the design of the work and the acquisition, analysis, or interpretation of data, drafted the manuscript or made critical revisions, approved of the final version to be published, and agree to be accountable for all aspects of the work. Guarantor: SS.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.