Background: Flow-diverter devices (FDDs) are new-generation stents placed in the parent artery at the level of the aneurysm neck to disrupt the intra-aneurysmal flow thus favoring intra-aneurysmal thrombosis. Objective: The objective of this review article is to define the indication and results of the treatment of intracranial aneurysms by FDD, reviewing 18 studies of endovascular treatment by FDDs for a total of 1704 aneurysms in 1483 patients. Methods: The medical literature on FDDs for intracranial aneurysms was reviewed from 2009 to December 2014. The keywords used were: “intracranial aneurysms,” “brain aneurysms,” “flow diverter,” “pipeline embolization device,” “silk flow diverter,” “surpass flow diverter” and “FRED flow diverter.” Results: The use of these stents is advisable mainly for unruptured aneurysms, particularly those located at the internal carotid artery or vertebral and basilar arteries, for fusiform and dissecting aneurysms and for saccular aneurysms with large necks and low dome-to-neck ratio. The rate of aneurysm occlusion progressively increases during follow-up (81.5% overall rate in this review). The non-negligible rate of ischemic (mean 4.1%) and hemorrhagic (mean 2.9%) complications, the neurological morbidity (mean 3.5%) and the reported mortality (mean 3.4%) are the main limits of this technique. Conclusion: Treatment with FDDs is a feasible and effective technique for unruptured aneurysms with complex anatomy (fusiform, dissecting, large neck, bifurcation with side branches) where coiling and clipping are difficult or impossible. Patient selection is very important to avoid complications and reduce the risk of morbidity and mortality. Further studies with longer follow-up are necessary to define the rate of complete occlusion.

Object: This study proposes a topographical classification of spheno-orbital meningiomas. Its aim was to define whether the different intraorbital localizations require different surgical approaches and have different recurrence rates and outcomes. Material and Methods: Sixty patients with spheno-orbital meningiomas operated upon between 1983 and 2003 were reviewed. Four types were identified according to the extent of intraorbital tumor invasion: I: lateral or superolateral (15 cases); II: medial and inferomedial (8 cases); III: orbital apex (25 cases); IV: diffuse (12 cases). Three surgical approaches were used: lateral orbitotomy (15 cases with lateral or superolateral tumors), supraorbital-pterional approach (42 cases, including all 8 inferomedial cases, all 25 orbital apex cases, and 9 of 12 diffuse tumors), and a fronto-temporal-orbitozygomatic approach (only 3 cases with diffuse meningiomas and large-scale tumor invasion in the infratemporal fossa and cavernous sinus). Results: Tumor removal was complete (Simpson grades I and II) in 40 cases, and incomplete in 20 (33.3%). There were two postoperative deaths (3.3%). A sufficient clinical follow-up was obtained in 52 cases. The clinical outcome was excellent in 26 patients (50%), good in 16 (30.8%), moderate in 6 (11.5%), and poor in 4 (7.7%). Twenty-two of 52 patients (42.3%) had tumor recurrence; however, 44 (84.6%) achieved tumor control after surgery alone through two or more operations. The recurrence rate was correlated with the Simpson grade of resection and the intraorbital tumor location. Significantly higher rates of recurrence were recorded for the orbital apex type (50%) and diffuse forms (60%), than for the inferomedial (28.5%) and superolateral forms (23%). Conclusions: Spheno-orbital meningiomas may be classified according to the location and extent of the intraorbital tumor invasion. The different localizations may require different surgical approaches, with different chances of complete removal. The location and extent of the intraorbital tumor results in different recurrence rates, lower for superolateral and inferomedial forms than for orbital apex and diffuse forms. Ziele: In dieser Arbeit wird eine topographische Klassifikation der sphenoorbitalen Meningeome vorgeschlagen. Ihr Ziel ist zu definieren inwieweit unterschiedliche intraorbitale Tumorausdehnungen unterschiedliche chirurgische Zugänge erforderlich machen und zu unterschiedlichen Rezidivraten und Ergebnissen führen. Patientengut und Methode: Sechzig Patienten mit sphenoorbitalen Meningeomen wurden zwischen 1983 und 2003 operiert und zusammengefasst. Gemäß der intraorbitalen Tumorausdehnung wurden 4 Typen identifiziert: I: lateral oder superolateral (15 Fälle); II: medial und inferomedial (8 Fälle); III: Orbitaspitze (25 Fälle); IV diffus (12 Fälle). Drei Zugänge wurden benutzt: laterale Orbitotomie (15 Fälle mit lateralen oder superolateralen Tumoren), supraorbital-pterionaler Zugang (42 Fälle, einschließlich alle 8 inferomedialen Tumoren, alle 25 Tumoren der Orbitaspitze und 9 von 12 diffusen Tumortypen), und fronto-temporo-orbitozygomatischer Zugang (nur 3 Fälle mit diffusen Meningeomen und großer Tumorausdehnung in die Fossa infratemporalis und den Sinus cavernosus). Ergebnisse: Die Tumorentfernung war komplett (Simpson Grad I und II) in 40 Fällen und inkomplett in 20 (33,3%). Es gab 2 postoperative Todesfälle (3,3%). Eine ausreichende Nachuntersuchung konnte in 52 Fällen erzielt werden. Das klinische Ergebnis war exzellent bei 26 Patienten (50%), gut bei 16 (30,8%), mäßig in 6 (11,5%) und schlecht in 4 (7,7%). 22 von 52 (42,3%) hatten ein Tumorrezidiv, jedoch bei 44 (84,6%) konnte eine Tumorkontrolle nach alleiniger Chirurgie mit 2 bis 3 Operationen erzielt werden. Die Rezidivrate korrelierte mit den Simpson Graden bei der Resektion und dem intraorbitalen Tumoranteil. Deutlich höhere Rezidivraten wurden festgestellt bei den Tumoren in der Orbitaspitze (50%) und bei den diffusen Wachstumsformen (60%), mehr als bei den inferomedialen (28,5%) und superolateralen Wachstumsformen (23%). Schlussfolgerungen: Sphenoorbitale Meningeome können gemäß ihrer Lokalisation und den intraorbitalen Tumoranteilen klassifiziert werden. Unterschiedliche Lokalisationen können unterschiedliche Zugangswege erfordern mit unterschiedlichen Chancen für eine komplette Tumorentfernung. Die Lokalisation und das Ausmaß des intraorbitalen Tumoranteils resultieren in verschiedenen Rezidivraten, die niedriger für superolateral und inferomediale Wachstumsformen sind als für Tumoren, die die Orbitaspitze befallen oder diffus wachsen.