Minim Invasive Neurosurg 2005; 48(5): 251-258
DOI: 10.1055/s-2005-915599
Original Article
© Georg Thieme Verlag Stuttgart · New York

The Keyhole Concept in Aneurysm Surgery - A Comparative Study: Keyhole versus Standard Craniotomy

J.  Paladino1 , G.  Mrak1 , P.  Miklić1 , H.  Jednacak1 , D.  Mihaljević1
  • 1Department of Neurosurgery, School of Medicine, University of Zagreb, Croatia
Further Information

Publication History

Publication Date:
01 December 2005 (online)


Objective: The purpose of the study is to compare the results of minimally invasive keyhole craniotomy and standard larger craniotomies in the surgical treatment of patients with intracranial aneurysms. Methods: In the past eight years 628 patients were operated by two experienced neurosurgical teams. The first group of 482 patients with 565 aneurysms were operated through a small keyhole craniotomy, using the eyebrow keyhole approach in particular. The remaining 146 patients with 167 aneurysms were operated using a standard craniotomy that included pterional/frontotemporal, frontoparietal parasagittal, and retrosigmoid suboccipital craniotomies. All operations were performed in the standard microsurgical technique using intraoperative evoked potential monitoring and endoscopic assistance in selected cases. Results: Most supratentorial aneurysms and basilar tip aneurysms were successfully operated through an eyebrow keyhole craniotomy. Distal MCA aneurysms as well as aneurysms on the MCA with a long M1 segment were operated through a temporal keyhole, and aneurysms of the distal PCA (P2 - P3) segment subtemporally. The frontoparietal parasagittal keyhole approach was used only for pericallosal artery aneurysms. Infratentorial aneurysms of the VA/PICA complex were operated via a retrosigmoid approach. On comparing the surgery results in patients with a keyhole craniotomy and those with standard craniotomy, similar outcomes were found for both groups, with excellent or very good outcomes (GOS 5 and 4) in 398 (82.57 %) patients from the keyhole craniotomy group, and in 116 (79.45 %) patients from the standard craniotomy group. The mortality rate in the keyhole group was 0.83 % (4 patients) and 2.05 % (3 patients) in the standard craniotomy group. Conclusion: Parallel treatment results in using two options - keyhole craniotomy and standard larger craniotomy - were analysed in the past eight years. Two experienced neurosurgical teams in performing both surgical approaches have reached almost similar morbidity and mortality rates, and overall surgical results. The type of craniotomy is selected according to the experience of the surgical team, and familiarity with certain approach. The authors have good experience with the minimally invasive approach for different intracranial pathology and recommend it especially in neurovascular surgery.


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Josip Paladino,Prof. M. D., Ph. D. 

Department of Neurosurgery · School of Medicine · University of Zagreb

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