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Introduction  Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology, landmarks are crucial in planning and performing complex approaches to the posterolateral skull base. By combining two major dependable structures—the asterion (A) and transverse process of the atlas (TPC1)—we investigate the A-TPC1 line in relation to the sigmoid sinus and in partitioning surgical approaches to the region. Methods  We dissected six cadaveric heads (12 sides) to expose the posterolateral skull base, including the mastoid and suboccipital bone, TPC1 and suboccipital triangle, distal jugular vein and internal carotid artery, and lower cranial nerves in the distal cervical region. We inspected the A-TPC1 line before and after drilling the mastoid and occipital bones and studied the relationship of the sigmoid sinus trajectory and major muscular elements related to the line. We retrospectively reviewed 31 head and neck computed tomography (CT) angiograms (62 total sides), excluding posterior fossa or cervical pathologies. Bone and vessels were reconstructed using three-dimensional segmentation software. We measured the distance between the A-TPC1 line and sigmoid sinus at different levels: posterior digastric point (DP), and maximal distances above and below the digastric notch. Results  A-TPC1 length averaged 65 mm and was posterior to the sigmoid sinus in all cadaver specimens, coming closest at the level of the DP. Using the transverse-asterion line as a rostrocaudal division and skull base as a horizontal plane, we divided the major surgical approaches into four quadrants: distal cervical/extreme lateral and jugular foramen (anteroinferior), presigmoid/petrosal (anterosuperior), retrosigmoid/suboccipital (posterosuperior), and far lateral/foramen magnum regions (posteroinferior). Radiographically, the A-TPC1 line was also posterior to the sigmoid sinus in all sides and came closest to the sinus at the level of DP (mean, 7 mm posterior; range, 0–18.7 mm). The maximal distance above the DP had a mean of 10.1 mm (range, 3.6–19.5 mm) and below the DP 5.2 mm (range, 0–20.7 mm). Conclusion  The A-TPC1 line is a helpful landmark reliably found posterior to the sigmoid sinus in cadaveric specimens and radiographic CT scans. It can corroborate the accuracy of neuronavigation, assist in minimizing the risk of sigmoid sinus injury, and is a useful tool in planning surgical approaches to the posterolateral skull base, both preoperatively and intraoperatively. [ABSTRACT FROM AUTHOR]

This article endeavors to describe and explain the constitution of modernity, its different trajectories, and its ongoing crisis using the Weberian concept of ‘legitimate order’, and by considering the changing relations between orders. One possible basis for the interpretation of the changing constitution of modernity – which involves, most significantly, a move beyond the great public/private dichotomy – is drawn from economic theory, or rather theories, of goods. The ability of certain orders to produce certain types of goods and to allocate them defines different types of society; in different societies, the same good will differ in nature and occupy a place within different property regimes. Changing relations can also be analyzed on the basis of the capacity of an order to impose upon others its negative externalities, and to manage effectively the production and allocation of its characteristic goods at different territorial scales. [ABSTRACT FROM AUTHOR]

This article stems from an awareness that the ‘European social model’ is marked – in the discourse that proposes it and in the policies that attempt to implement it – by an original combination of the dimensions of economic competitiveness and social cohesion. Today, this combination is in the midst of a crisis whose nature and outcome are variously interpreted, in politics as in social sciences. The current debate would have much to gain from the use of several classic analytical categories, which, though well enough known, are rarely if ever applied in this context. After a schematic presentation of the characteristics that discussion of the European model has now assumed, an institutional approach to interpreting it will be proposed which revolves around the Weberian concept of ‘legitimate order’. Particular attention will be devoted to the organizational means whereby policies are formulated and pursued, and the territorial dimension of policies and their effects will be discussed. The concluding remarks will present policy implications and considerations concerning the present crisis and possible developments of the European model, elaborated on the basis of the proposed methodological approach. [ABSTRACT FROM PUBLISHER]

Fourth ventricle meningiomas (FVMs) are rare, often misdiagnosed, lesions. To the best of our knowledge, 47 cases have been reported in the literature: we describe our series of three cases treated at our Institution, focusing on some diagnostic tips and intraoperative features of these tumours. Our three patients have a history of headache. Gait disturbances, vomiting and/or diplopia complicated the clinical picture before the referral at our Department. The operations were uneventful, and the patients fully recovered from neurological symptoms. They are free of recurrence at a median follow-up of 19 years. FVMs are rare lesions, which are difficult to differentiate preoperatively from the much more common ependymomas. A preoperative distinction would be extremely advantageous: indeed, although both tumours share similar radiological and clinical patterns, they clearly differ as to surgical difficulty and outcome. In fact, meningiomas are comparatively easier to remove, granting better clinical results. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the reliability, safety and accuracy of a the frameless stereotactic system in our clinical series and the differences between head fixation by means of a standard Mayfield head holder and the pinless FESS frame, and to evaluate the usefulness of biopsy targeting on the basis of magnetic resonance spectroscopy (MRS) data. Methods: The spectroscopic analysis was used to facilitate the targeting of the lesion. The fusion image function embedded in the Neuronavigation Unit was used postoperatively to assess the level of accuracy of the biopsy. The grading of the glioma specimens was correlated to the spectroscopic data. Results: 296 patients underwent cerebral biopsy in 8 years. The diagnostic yield was 99.7%. The spectroscopic choline/N-acetyl aspartate ratio in different areas of the same tumor correlated well with the histological grading of the lesion. Conclusion: The frameless stereotactic systems guarantee excellent biopsy results. Advanced imaging, in particular MRS, facilitates the correct targeting of nonenhancing lesions. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Clinoidal meningiomas are a heterogenous group of tumors that share a common origin from the anterior clinoidal process. A correct understanding of the characteristics of the tumor in individual patients guarantees the best treatment. We propose to merge Al-Mefty's and Risi's criteria to improve the predictive value of these classifications with respect to the degree of removal and to the postoperative morbidity. [ABSTRACT FROM AUTHOR]

This article examines cooperative modes of regulation of local economies that in Europe increasingly take the form of concertation (partnership) – i.e. formalized agreement on common goals stated by collective actors with traditionally/potentially contrasting interests. This kind of agreement (‘pacts’) is increasingly institutionalized; ‘institutionalization’ being the process through which certain behaviours are steadily promoted, required, even made obligatory, by actors other than those putting them into effect, who demand conformity to their values and beliefs in return for making resources available. The process in question is particularly visible in EU countries, and it can be interpreted both as an opportunity to construct a model of a social Europe and as an opportunity to defend the features of this model that were subject to rapid erosion during the 1990s. Recurrent forms of partnership are: public–private and public–public partnerships; ‘regionalized’ industrial relations; ‘second–generation’ industrial districts; urban strategic planning; and territorial pacts. To order them, a typology is proposed on the basis of the dichotomy between exogenous/endogenous actors/resources. Three main constraints to an effective working of local concertation are then discussed: local presence of ‘global players’; excessive institutionalization; and lack of adequate implementation structures. Starting from the latter, some working hypotheses are proposed on a new ‘organizational population’, namely, the organizations of local development. Cet article examine les modes de régulation collectifs des économies locales, ceux–ci prenant de plus en plus souvent la forme d’une concertation (partenariat), accord formel sur des objectifs communs énoncés par un collectif d’acteurs dont les intérêts sont habituellement ou éventuellement opposés. Ce type d’accord (pacte) s’institutionnalise progressivement au travers d’un processus grâce auquel certains comportements sont toujours encouragés, demandés, voire exigés, par des acteurs qui, d’une part, ne sont pas ceux qui les appliquent et, d’autre part, réclament le respect de leurs valeurs et convictions en contrepartie de la mise à disposition de ressources. Ce processus, particulièrement évident dans les pays de l’U.E., peut s’interpréter à la fois comme une possibilité de construire un modèle d’Europe sociale et comme une chance de défendre les caractéristiques de ce modèle alors que celles–ci se sont rapidement dégradées dans les années 1990. Les formes récurrentes de partenariat sont: partenariats public–privé et public–public, liens industriels régionaux, districts industriels ‘de deuxième génération’, urbanisme stratégique et pactes territoriaux. L’article propose une typologie basée sur les dichotomies acteurs/ressources exogènes/endogènes. Il déduit ensuite les trois principales entraves à une concertation locale efficace: la présence locale de ‘joueurs de niveau international‘, un excès d’institutionnalisation et un manque de structures de mise en œuvre appropriées. A partir de ce dernier point, sont présentées quelques hypothèses de travail sur une nouvelle ‘population organisationnelle‘, autrement dit des organisations de développement local. [ABSTRACT FROM AUTHOR]

A correlation between radiation therapy and cavernoma has been suspected since 1994. Since then, only a few cases of radio-induced cavernomas have been reported in the literature (85 patients). Most of them were children, and the most frequent original tumour had been medulloblastoma. The authors report a case of two cystic cavernous angiomas after radiation therapy for atypical meningioma in adult woman. This is the first case of cavernous angioma after radiotherapy for low grade meningioma. A 39-year-old, Latin american woman was operated on for a frontal atypical meningioma with intradiploic component and adjuvant radiotherapy was delivered (6000 cGy local brain irradiation, fractionated over 6 weeks). Follow-up MR imaging showed no recurrences of the tumour and no other lesions. Ten years later, at the age of 49, she consulted for progressive drug-resistant headache. MR imaging revealed two new well defined areas of different signal intensity at the surface of each frontal pole. Both lesions were surgically removed; the histopathological diagnosis was cavernous angioma. This is the first case of cavernous angioma after radiation therapy for atypical meningioma : it confirms the development of these lesions after standard radiation therapy also in patients previously affected by non-malignant tumours. [ABSTRACT FROM AUTHOR]

Introduction  Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology, landmarks are crucial in planning and performing complex approaches to the posterolateral skull base. By combining two major dependable structures-the asterion (A) and transverse process of the atlas (TPC1)-we investigate the A-TPC1 line in relation to the sigmoid sinus and in partitioning surgical approaches to the region. Methods  We dissected six cadaveric heads (12 sides) to expose the posterolateral skull base, including the mastoid and suboccipital bone, TPC1 and suboccipital triangle, distal jugular vein and internal carotid artery, and lower cranial nerves in the distal cervical region. We inspected the A-TPC1 line before and after drilling the mastoid and occipital bones and studied the relationship of the sigmoid sinus trajectory and major muscular elements related to the line. We retrospectively reviewed 31 head and neck computed tomography (CT) angiograms (62 total sides), excluding posterior fossa or cervical pathologies. Bone and vessels were reconstructed using three-dimensional segmentation software. We measured the distance between the A-TPC1 line and sigmoid sinus at different levels: posterior digastric point (DP), and maximal distances above and below the digastric notch. Results  A-TPC1 length averaged 65 mm and was posterior to the sigmoid sinus in all cadaver specimens, coming closest at the level of the DP. Using the transverse-asterion line as a rostrocaudal division and skull base as a horizontal plane, we divided the major surgical approaches into four quadrants: distal cervical/extreme lateral and jugular foramen (anteroinferior), presigmoid/petrosal (anterosuperior), retrosigmoid/suboccipital (posterosuperior), and far lateral/foramen magnum regions (posteroinferior). Radiographically, the A-TPC1 line was also posterior to the sigmoid sinus in all sides and came closest to the sinus at the level of DP (mean, 7 mm posterior; range, 0-18.7 mm). The maximal distance above the DP had a mean of 10.1 mm (range, 3.6-19.5 mm) and below the DP 5.2 mm (range, 0-20.7 mm). Conclusion  The A-TPC1 line is a helpful landmark reliably found posterior to the sigmoid sinus in cadaveric specimens and radiographic CT scans. It can corroborate the accuracy of neuronavigation, assist in minimizing the risk of sigmoid sinus injury, and is a useful tool in planning surgical approaches to the posterolateral skull base, both preoperatively and intraoperatively., Competing Interests: Conflict of Interest None declared., (Thieme. All rights reserved.)

Postoperative extradural hematoma (POEH) is a possible complication after head surgery, often neglected in the literature. In a single surgeon experience we found 13 cases of POEH (0.8%). We distinguished two subtypes: (1) larger hematomas (>40 cc) with typical features and overt clinical picture that always needed evacuation, and (2) smaller hematomas (<40 cc) with insidious clinical onset and different radiological features compared with traumatic and spontaneous extradural hematomas. On the basis of our experience, we propose that clinical picture and radiologic appearance lead the decision between conservative or interventional treatment of type II hematomas., (Georg Thieme Verlag KG Stuttgart · New York.)

Background: Few reports exist in the literature about the use of endoscope assistance in the identification of structures in the posterior fossa., Objective: To asses the advantage of endoscopic assistance in the epidural subtemporal and Kawase approaches by studying anatomic exposure and surgical freedom in the posterior cranial fossa., Methods: Twelve epidural subtemporal approaches were performed on 6 adult cadaveric heads. On the same specimens, 6 endoscope-assisted subtemporal approaches and 6 Kawase approaches were then performed. At the end of each Kawase approach, endoscope assistance was used. The microsurgical observations were performed with a surgical microscope with magnification ranging from 4 x to 40 x. Endoscopic observations were made with a 0 degrees , 4-mm rod-lens endoscope. Anatomic exposure and surgical freedom were analyzed., Results: Endoscopic assistance during the epidural subtemporal approach increased the anatomic exposure 3 mm superiorly, 20 mm inferiorly, and 10 mm medially from the trigeminal nerve. Surgical freedom was limited in the temporal lobe, the petrous apex, and the trigeminal nerve. The amount of increased anatomic exposure obtained with endoscopic assistance during the Kawase approach was 26 mm inferiorly and medially from the trigeminal nerve. Surgical freedom was limited by the brainstem and the depth of the posterior cranial fossa., Conclusion: The endoscope-assisted subtemporal approach can be useful in visualizing tumor in the posterior fossa. It can help the surgeon in planning further surgical steps through consideration of the size, extension, and adherence of the tumor to surrounding structures. The endoscope-assisted Kawase approach permits maximum anatomic exposure of the posterior cranial fossa, although the deepest neurovascular structures could be better addressed with more direct approaches.

Objective: Today, meningiomas with primary or, more commonly, secondary involvement of the cavernous sinus remain a surgical challenge. Anatomic research on cadaver specimens, together with the advances made in cranial base and microvascular surgery over the past 2 decades, have made it possible to completely resect lesions within the cavernous sinus. However, the technical complexity of some procedures, coupled with the current availability of less-invasive therapeutic options, makes the rate of complications related to surgical extirpation of intracavernous meningiomas unacceptably high, especially regarding permanent neurological morbidity and mortality. Currently, indications, timing, and multimodal treatments with surgery and radiotherapy represent the main topics of discussion concerning these lesions., Methods: One hundred forty-seven patients underwent surgery between 1985 and 2003. The patients were retrospectively divided into 2 groups according to the type of surgical treatment: group A (open sinus surgery) and group B (closed sinus surgery). The mean follow-up time was 9.7 years., Results: Early postoperative morbidity and permanent postoperative morbidity showed significant differences between the groups. At long-term follow-up, we found no statistical differences in the incidence of recurrences and progressions. Only patients treated with postoperative radiation therapy (81.5%) showed clinicoradiological stability., Conclusion: Growth control and preservation of neurological functions are the primary goals in the treatment of cavernous sinus meningiomas. In most cases, surgery and radiosurgery alone do not reach the primary goals, and unresolved issues remain. Therefore, we have developed a treatment algorithm as a guide to the best therapeutic options for the most common presentations of the disease.

Object: The authors present the surgical results obtained using the anterolateral approach to the craniocervical junction (CCJ) to resect a lesion with an extradural component located anterolateral to the foramen magnum and upper cervical spine., Methods: The anterolateral approach, which is a presternomastoid retrojugular route to the CCJ, was performed in 14 patients. The skin incision follows the anterior edge of the sternomastoid muscle. The vertebral artery (VA) was exposed at C-1. This approach was extended either down to the cervical spine or anteriorly to the jugular foramen, according to specific requirements. Two patients had previously undergone other surgical procedures. The follow-up period ranged from 4 months to 6.2 years. The tumor resection was complete in 11 cases and subtotal in two. In a case of vertebral coiling, a vein graft was interposed between the V1 and the V3 segments of the VA, and the bypass was still patent at the 2-year follow-up examination. In two cases involving a glomus tumor, there was a transitory postoperative seventh cranial nerve deficit., Conclusions: The aforementioned technique allows for sufficient access to lesions located anterolateral to the CCJ. It is indicated in cases in which lesions exhibit a significant extradural component, and it provides good control of the VA, the cervical portion of the internal carotid artery, sigmoid-jugular complex, and lower cranial nerves. This approach can easily be combined with a posterolateral approach and can be extended anteriorly toward the jugular foramen and inferiorly toward the lower cervical spine.