Distal Anterior Cerebral Artery Aneurysms - Helda - Helsinki.fi

99 Pages·2008·2.78 MB·English

by  Martin Lehecka

Distal Anterior
Cerebral Artery
Aneurysms
Martin Lehečka
ISBN 978-952-92-4914-5 (paperback)
ISBN 978-952-10-5176-0 (PDF)
http://ethesis.helsinki.fi/
Helsinki University Press
Helsinki 2009 University of Helsinki 2009
From the Department of Neurosurgery
Helsinki University Central Hospital
University of Helsinki
Helsinki, Finland
Distal Anterior Cerebral Artery
Aneurysms
Martin Lehečka
Academic Dissertation
To be presented with the permission
of the Faculty of Medicine of the University of Helsinki
for public discussion in the Lecture hall  of Töölö Hospital
on February 6th, 2009 at 2 o’clock noon.
Helsinki 2009

Supervised by:
Professor Juha Hernesniemi, M.D., Ph.D.
Department of Neurosurgery
Helsinki University Central Hospital
Helsinki, Finland
Associate Professor Mika Niemelä, M.D., Ph.D.
Department of Neurosurgery
Helsinki University Central Hospital
Helsinki, Finland
Reviewed by:
Professor Juha Öhman, M.D., Ph.D.
Department on Neurosurgery
Tampere University Hospital
Tampere, Finland
Associate Professor Timo Kumpulainen, M.D., Ph.D.
Department of Neurosurgery
Oulu University Hospital
Oulu, Finland
To be discussed with:
Professor Robert F. Spetzler, M.D.
Director, Barrow Neurological Institute
J.N. Harber Chairman of Neurological Surgery
Professor, Section of Neurosurgery, University of Arizona
Phoenix, Arizona
st edition 2009
© Martin Lehečka 2009
Cover and illustrations © Martin Lehečka 2009
ISBN 978-952-92-494-5 (paperback)
ISBN 978-952-0-576-0 (PDF)
http://ethesis.helsinki.fi/
Helsinki University Press
Helsinki
2009
2
To my grandfather

Author’s contact information:
Martin Lehečka
Department of Neurosurgery
Helsinki University Central Hospital
Topeliuksenkatu 5
00260 Helsinki
Finland
mobile: +58 50 427 2500
fax: +58 9 47 87560
e-mail: [email protected]
4
Table of conTenTs
Table of contents
Abstract 11
Abbreviations 12
List of original publications 13
1. Introduction 14
2. Review of literature 15
2.1. IntracranIal aneurysms 15
2... Prevalence of intracranial aneurysms 5
2..2. Pathobiology of intracranial aneurysms 5
2.1.2.1. Morphology and formation of intracranial aneurysms 15
2.1.2.2. Genetics of intracranial aneurysms 15
2.1.2.3. Histology of intracranial aneurysms 15
2... Subarachnoid hemorrhage 6
2.1.3.1. Incidence of SAH 16
2.1.3.2. Natural history of ruptured intracranial aneurysms 16
2..4. Treatment of ruptured intracranial aneurysms 6
2.1.4.1. Rebleeding 16
2.1.4.2. Cerebral vasospasm 17
2.1.4.3. Other complications of SAH 17
2..5. Outcomes for ruptured IAs 7
2.1.5.1. Outcome assessment 17
2.1.5.2. Treatment outcome 17
2.1.5.3. Predictors for outcome after SAH 17
2..6. Long-term follow-up after SAH 8
2.1.6.1. De novo aneurysms and rebleeding 18
2.1.6.2. Long-term mortality 18
2..7. Management of unruptured IAs 8
2.2. HIstory of IntracranIal aneurysm treatment 19
2.2. Before microneurosurgery 9
2.2.1.1. Intracranial aneurysms in historical context 19
2.2.1.2. Hunterian ligation 19
2.2.1.3. Carotid occlusion 20
2.2.1.4. Cerebral angiography 20
2.2.1.5. Wrapping and trapping 21
2.2.1.6. Clipping 21
2.2.1.7. Aneurysm clip development 21
2.2.2. Microneurosurgery 22
2.2.2.1. Operating microscope 22
2.2.2.2. Development of microneurosurgery 22
2.2.2.3. Other technical developments 23
5
Table of conTenTs
2.2.2.4. Microneurosurgery applied to intracranial aneurysms 23
2.2.. Endovascular surgery 24
2.2.3.1. Balloon occlusion 24
2.2.3.2. Coiling 24
2.2.4. Aneurysm surgery in Finland 25
2.2.4.1. Aarno Snellman, founder of Finnish neurosurgery 25
2.2.4.2. Angiography in Finland 25
2.2.4.3. World War II and the late 1940s 25
2.2.4.4. Initial steps in aneurysm surgery 26
2.2.4.5. Microneurosurgery and endovascular surgery 27
2.3. mIcrosurgIcal anatomy for Daca aneurysms 28
2... Anterior cerebral artery 28
2.3.1.1. A1 segment of ACA 28
2.3.1.2. Anterior communicating artery (ACoA) complex 28
2.3.1.3. Perforating branches of ACoA 29
2.3.1.4. A2 segment 29
2.3.1.5. Arterial branches of A2 segment 30
2.3.1.6. Recurrent artery of Heubner (RAH) 30
2.3.1.7. Orbitofrontal artery (OFA) 31
2.3.1.8. Frontopolar artery (FPA) 31
2.3.1.9. Basal perforating branches 31
2.3.1.10. A3 segment and its branches 31
2.3.1.11. Callosomarginal artery (CMA) 31
2.3.1.12. A4 and A5 segments and their cortical branches 32
2.3.1.13. Anatomic anomalies of ACA 32
2..2. Interhemispheric fissure 
2... Venous structures 
2..4. Corpus callosum 4
2.4. DIstal anterIor cerebral artery aneurysms 35
2.4.. Incidence and location of DACA aneurysms 5
2.4.1.1. Aneurysms of the ACA 35
2.4.1.2. A2As (Proximal pericallosal aneurysms) 35
2.4.1.3. A3As (Classical pericallosal aneurysms) 36
2.4.1.4. AdistAs (Distal pericallosal aneurysms) 36
2.4.2. Clinical symptoms 6
2.4.. Anatomic features 6
2.4.3.1. Size 36
2.4.3.2. Multiple aneurysms 37
2.4.3.3. ICH and IVH 37
2.4.3.4. Association with ACA anomalies 37
2.4.3.5. Association with AVMs 38
2.4.4. Special subgroups of DACA aneurysms 8
2.4.4.1. Giant DACA aneurysms 38
2.4.4.2. Aneurysms associated with azygos ACA 38
2.4.4.3. Traumatic DACA aneurysms 38
6
Table of conTenTs
2.4.5. Imaging of DACA aneurysms 9
2.4.6. Treatment of DACA aneurysms 40
2.4.6.1. History 40
2.4.6.2. Conservative treatment 40
2.4.6.3. Direct surgery before microneurosurgery 42
2.4.6.4. Microneurosurgery for DACA aneurysms 42
2.4.6.5. Technical difficulties in DACA aneurysm surgery 45
2.4.6.6. Endovascular treatment 45
2.4.6.7. Technical difficulties in coiling of DACA aneurysms 46
2.4.7. Outcome 46
2.4.7.1. Short-term outcome 46
2.4.7.2. Predictors of short-term outcome 46
2.4.7.3. Long-term outcome 46
3. Aims of the study 47
4. Patients, materials and methods 48
4.1. PublIcatIon I: anatomIc features of Daca aneurysms 48
4... Patients and images 48
4..2. Image analysis 49
4... Statistical analysis 49
4.2. PublIcatIon II: treatment anD outcome of Daca aneurysms 49
4.2.. Patients 49
4.2.2. Data collection 50
4.2.. Statistical analysis 50
4.3. PublIcatIon III: long-term outcome of ruPtureD Daca aneurysms 51
4... Patients 5
4..2. Follow-up 5
4... Statistical analysis 5
4.4. PublIcatIons IV-VI: mIcroneurosurgIcal management of Daca aneurysms 51
4.4.. Patients (Kuopio Cerebral Aneurysm Database) 5
4.4.2. Analysis of microneurosurgical technique 5
4.4.. Microneurosurgical videos 52
5. Results 53
5.1. IncIDence of Daca aneurysms (PublIcatIons IV-VI) 53
5.2. anatomy of Daca aneurysms (PublIcatIon I) 53
5.2.. Microneurosurgical classification 5
5.2.2. Aneurysm size 54
5.2.. Dome and base 54
5.2.4. Multiple aneurysms 55
5.2.5. Anomalies of ACA 56
5.2.5.1. Azygos ACA 56
5.2.5.2. Bihemispheric ACA 56
5.2.5.3. Triplication of ACA 56
7
Table of conTenTs
5.2.6. Associated AVMs 57
5.3. saH from ruPtureD Daca aneurysm (PublIcatIon II, Part b) 57
5... Age, presentation, and clinical condition 57
5..2. Radiological features 57
5.3.2.1. CT findings 57
5.3.2.2. Angiographic findings (DSA, CTA, MRA) 58
5.4. treatment anD outcome of Daca aneurysms (PublIcatIon II) 58
5.4.. Ruptured DACA aneurysms 96–979 (publication II, part a) 58
5.4.2. Ruptured DACA aneurysms 980–2005 (publication II, part b) 58
5.4.2.1. Microneurosurgical clipping 58
5.4.2.2. Coiling 59
5.4.2.3. Outcome at one year 60
5.4.2.4. Factors predicting outcome at one year 60
5.4.. Unruptured DACA aneurysms 980–2005 (publication II, part b) 6
5.4.3.1. Unruptured DACA aneurysms without acute SAH 61
5.4.3.2. Unruptured DACA aneurysms with acute SAH 61
5.5. long-term follow-uP of ruPtureD Daca aneurysms (PublIcatIon III) 61
5.5.. Rebleeding 6
5.5.2. Mortality 6
5.5.2.1. Early mortality 61
5.5.2.2. Long-term mortality 62
5.5.. Excess mortality 62
5.6. mIcroneurosurgIcal tecHnIque for clIPPIng Daca aneurysms (PublIcatIons IV–VI) 63
5.6.. Approach 6
5.6.2. Positioning, craniotomy and dural opening 64
5.6.. CSF drainage 64
5.6.4. Removal of ICH 65
5.6.5. Dissection towards the aneurysm 65
5.6.6. Dissection of the aneurysm 68
5.6.7. Temporary clipping 68
5.6.8. Clipping of the aneurysm 68
5.6.9. Intraoperative aneurysm rupture 69
5.6.0. Verification of clipping 69
5.6.. Associated aneurysms 69
5.6.2. Special considerations for each DACA aneurysm location 69
5.6.12.1. Frontobasal A2As (publication IV) 69
5.6.12.2. A2 trunk A2As (publication IV) 70
5.6.12.3. Inferior A3As (publication V) 71
5.6.12.4. Anterior A3As (publication V) 72
5.6.12.5. Superior A3As (publication V) 72
5.6.12.6. A4 and A5 aneurysms (publication VI) 73
5.6.12.7. Distal branch AdistAs (publication VI) 74
6. Discussion 75
6.1. anatomIc features 75
8
Table of conTenTs
6... DACA aneurysm locations 75
6..2. Aneurysm size and dome orientation 75
6... Aneurysm base and associated branches 75
6..4. ACA anomalies 76
6..5. Associated aneurysms and AVMs 76
6..6. ICHs from ruptured DACA aneurysms 77
6..7. Imaging of DACA aneurysms and CTA 77
6.2. treatment of Daca aneurysms 77
6.2.. Clipping of DACA aneurysms 77
6.2.2. Coiling of DACA aneurysms 78
6.3. outcome 78
6... Ruptured DACA aneurysms 78
6.3.1.1. One year outcome 78
6.3.1.2. Predictors of outcome at one year 79
6.3.1.3. Neurological deficits 79
6..2. Unruptured DACA aneurysms 79
6.4. long-term follow-uP 80
6.4.. Rebleeding from clipped DACA aneurysms 80
6.4.2. Recurrent SAH and de novo aneurysms 80
6.4.. Mortality 80
6.4.4. Excess mortality 80
6.4.5. Long-term angiographic screening 8
6.5. future trenDs 81
7. Conclusions 84
List of 12 supplementary videos on microneurosurgery of DACA aneurysms 85
Acknowledgments 86
References 88
9