Considerations in the surgical treatment of superior-wall type aneurysm at the proximal (M1) segment of the middle cerebral artery

Acta Neurochir (Wien). 2004 Sep;146(9):967-72; discussion 972. doi: 10.1007/s00701-004-0325-1. Epub 2004 Jul 12.


Objective: To present our experience and analyze the risks of neck clipping for superior-wall type aneurysms of the proximal segment of the middle cerebral artery (M1-Sup aneurysm).

Methods: Of 14 patients with M1-Sup aneurysms, 4 suffered postoperative infarctions in the territory of the lenticulostriate arteries (LSA) or fronto-orbital arteries. We re-examined our intraoperative findings and clinical records in an effort to identify possible causes.

Results: The patency of the LSA was confirmed at the end of surgery in all 14 cases. We posit that temporary occlusion of the LSA by a permanent clip resulted in delayed obstruction of the LSA in 3 patients. Other possibilities we considered were relatively long temporary occlusion of the M1, slipping of the clips and twisting of the clip blades after release of the brain retractors.

Conclusion: M1-Sup aneurysms are some of the most complicated aneurysms; they carry the risk of perforator injury during neck clipping. Surgical considerations to avoid perforator injury are discussed.

MeSH terms

  • Adult
  • Aged
  • Basal Ganglia / blood supply
  • Brain Infarction / etiology
  • Cerebral Arteries / pathology*
  • Female
  • Humans
  • Intracranial Aneurysm / surgery*
  • Male
  • Middle Aged
  • Middle Cerebral Artery / pathology
  • Retrospective Studies
  • Risk Factors
  • Surgical Instruments