AsanadditiontotheEuropeanpostgraduatetrainingsystemforyoung neurosurgeons, we began to publish in 1974 this series of Advancesand Technical Standards in Neurosurgery which was later sponsored by the EuropeanAssociationofNeurosurgicalSocieties. This series was ?rst discussed in 1972 at a combined meeting of the Italian and German Neurosurgical Societies in Taormina, the founding fathersoftheseriesbeingJeanBrihaye,BernardPertuiset,FritzLoewand HugoKrayenbuhl. ThuswereestablishedtheprinciplesofEuropean- operationwhich havebeenbornfromthe Europeanspirit,?ourishedin theEuropeanAssociation,andhavebeenassociatedthroughoutwiththis series. ThefactthattheEnglishlanguageisnowtheinternationalmediumfor communicationatEuropeanscienti?cconferencesisagreatassetinterms ofmutualunderstanding. Thereforewehavedecidedtopublishallcont- butionsinEnglish,regardlessofthenativelanguageoftheauthors. All contributions are submitted to the entire editorial board before publicationofanyvolumeforscrutinyandsuggestionsforrevision. Ourseriesisnotintendedtocompetewiththepublicationsoforiginal scienti?cpapersinotherneurosurgicaljournals. Ourintentionis,rather,to present?eldsofneurosurgeryandrelatedareasinwhichimportantrecent advanceshavebeenmade. Thecontributionsarewrittenbyspecialistsin thegiven?eldsandconstitutethe?rstpartofeachvolume. Inthesecondpartofeachvolume,wepublishdetaileddescriptionsof standardoperativeproceduresandindepthreviewsofestablishedkno- edge in all aspects of neurosurgery, furnished by experienced clinicians. This part is intended primarily to assist young neurosurgeons in their postgraduatetraining. However,weareconvincedthatitwillalsobeu- fultoexperienced,fullytrainedneurosurgeons. We hope therefore that surgeons not only in Europe, but also throughouttheworld,willpro?tbythisseriesofAdvancesandTechnical StandardsinNeurosurgery. TheEditors Contents ListofContributors...XIII Advances .. Gene Technology Based Therapies in the Brain. T. Wirth1,4 and S. Yla- Herttuala1,2,3, 1A. I. Virtanen Institute,University of Kuopio, Kuopio,F- land, 2DepartmentofMedicine,UniversityofKuopioandGeneTherapyUnit, Kuopio, Finland, 3Gene Therapy Unit, Kuopio University Hospital, Kuopio, Finland,4ArkTherapeuticsOy,Kuopio,Finland Abstract...3 IntroductiontoGeneTherapy:ThePast,PresentandFuture...4 PotentialAreasforGeneTherapyintheBrain...6 GeneTherapyforParkinson'sDisease...7 GeneTherapyforAlzheimer'sDisease...8 GeneTherapyforVascularBrainDiseases...9 GeneTherapyforBrainTumours...11 ChallengesofGeneTherapyintheBrain...12 GeneTransferVectors...15 ViralGeneTransferVectors...17 Retroviruses...17 HerpesSimplexVirus-1(HSV-1)...17 Adenoviruses...18 Adeno-AssociatedVirus(AAV's)...18 Non-ViralVectors...19 Ethics...20 ConcludingRemarks...21 Acknowledgement...21 References...21 VIII Contents TechnicalStandards AnatomyoftheOrbitanditsSurgicalApproach. G. Hayek,Ph. Mercier,and H. D. Fournier, Laboratory of Anatomy, Faculty of Medicine, University of Angers,Angers,France Abstract...35 Introduction...36 AnatomyoftheOrbit...36 TheOrbitalCavity...36 TheOrbitalFasciaorPeriorbita...38 OrbitalContents...39 OrbitalMuscles...40 TheArteriesoftheOrbit...42 VeinsoftheOrbit...47 NervesoftheOrbit...48 LacrymalGland...55 ApproachRoutestotheOrbit...56 Incision...56 TheLateralApproachRoute...57 OsteoplasticTechniques...58 Non-OsteoplasticTechniques...58 TheSuperiorApproachRoute...60 TheHybridLateral/SuperiorRoute...63 Discussion...