The base of the skull is the foundation on which the brain rests. It is a complex anatomical region located beneath the brain and in front of the brain stem, behind the face.
This is one of the body’s most complex anatomical regions.
The multiple bone structures that make it up are crossed by :
- vessels that supply blood to the brain (internal carotid artery, vertebral artery, etc.),
- the brain stem, which becomes the spinal cord in the spinal canal through the foramen magnum,
- the controlling nerves :
- sense organs (sight, smell, hearing, taste), lacrimation and salivation,
- the oculomotor muscles that enable the eyeball to move,
- superficial and deep facial muscles (mimicry, mastication),
- muscles of the tongue, palate and pharynx involved in swallowing and voice,
- sensitivity of the face, cornea, nasal cavities, mouth and pharynx
The base of the skull is therefore a tangle of bony, sensory, nervous, vascular and muscular structures, all highly functional and vital for some.
What are the causes?
The precise cause and mechanisms of meningioma development are not known, but a number of risk factors have been clearly identified. Certain factors can be considered as the cause of meningioma, even if the mechanisms are not clearly elucidated.
- One clearly established risk factor is exposure to ionizing radiation. Indeed, people who, for other reasons, have had cranial radiotherapy, particularly in childhood, are at greater risk of developing one or more meningiomas.
- The presence of certain genes inherited from ancestors
- Certain genetic diseases such as neurofibromatosis
- Hormonal factors. Meningiomas are more common in women. Their growth can accelerate during pregnancy, and they can sometimes decrease in size after delivery.
- Among hormonal factors, it has now been proven that taking progestin-only drugs promotes meningiomas. Progestins are drugs used in gynecological diseases (endometriosis, uterine fibroids, particularly long and/or heavy periods, cycle disorders), in hormone replacement therapy (including menopause), as oral contraceptives or in intrauterine devices, but also in obstetrics (infertility due to luteal insufficiency, recurrent miscarriages).
- Certain progestogens, such as cyproterone acetate (Androcur*), Nomegestrol acetate (Lutenyl*), chlormadinone acetate (Luteran*) may be the cause. Many other progestogens play a role in the genesis and growth of meningiomas to varying degrees. It is possible that some patients are more likely than others to develop one or more meningiomas under the influence of these progestin treatments. This is currently the subject of a great deal of research.
- Our team was the first to identify the risk of meningioma with cyproterone acetate.
- Does cyproterone acetate promote meningiomatosis? 56th Congress of the French National Society of Internal Medicine
(Link to our first abstract in 2007: https: //www.em-consulte.com/article/67674/article/communications-orales I’d also like the PDF of this article to appear by clicking on “Oral communication 083, Page S362”. The pdf is attached.
- Does cyproterone acetate promote multiple meningiomas? 10th European Congress of Endocrinology
Link: https://www.endocrine-abstracts.org/ea/0016/ea0016p158
and with normegestrol acetate (Link to publication: https: //link.springer.com/article/10.1007/s00701-019-03848-x). This has been one of our department’s major research topics since the arrival of Prof. Sébastien Froelich in 2011. This research has been the subject of numerous publications and is carried out in close collaboration with the Epi-phare agency(https://www.epi-phare.fr/)(Dr Alain Weill) and the ANSM(https://ansm.sante.fr/).
- The use of some of these progestin treatments is now subject to very strict recommendations from the ANSM (Link).
- Androcur* and meningioma risk (link: https: //ansm.sante.fr/dossiers-thematiques/androcur-et-risque-de-meningiome)
- Lunenyl*, Luteran* and the risk of meningiomas (link: https: //ansm.sante.fr/dossiers-thematiques/lutenyl-luteran
- Coprone*, depo-provera*, surgestone* (Link: https://ansm.sante.fr/actualites/colprone-depo-provera-et-surgestone-premieres-recommandations-pour-limiter-le-risque-de-meningiome
List of our publications :
Prolonged use of nomegestrol acetate and risk of intracranial meningioma: a population-based cohort study
Pierre Nguyen, Noémie Roland, Anke Neumann, Léa Hoisnard, Thibault Passeri, Lise Duranteau, Joël Coste, Sébastien Froelich, Mahmoud Zureik, Alain Weill
Link: https: //www.ncbi.nlm.nih.gov/pmc/articles/PMC11127190/pdf/main.pdf
Use of progestogens and the risk of intracranial meningioma: national case-control study. Roland N, Neumann A, Hoisnard L, Duranteau L, Froelich S, Zureik M, Weill A.BMJ. 2024 Mar 27;384:e078078.
Link: https: //www.ncbi.nlm.nih.gov/pmc/articles/PMC10966896/
Florea SM, Passeri T, Abbritti R, Bernat AL, Fontanel S, Yoldjian I, Funck-Brentano T, Weill A, Mandonnet E, Froelich S.J Neurosurg. 2023 Mar 3;139(4):944-952
Link: https: //thejns.org/view/journals/j-neurosurg/139/4/article-p944.xml
Hoisnard L, Laanani M, Passeri T, Duranteau L, Coste J, Zureik M, Froelich S, Weill A.Eur J Neurol. 2022 Sep;29(9):2801-2809.
Link: https: //www.ncbi.nlm.nih.gov/pmc/articles/PMC9543130/
The tumours and the three bumps.
Bousson V, Guichard JP, Froelich S, Orcel P.Lancet Oncol. 2022 Jan;23(1):e44.
Link: https: //www.thelancet.com/journals/lanonc/article/PIIS1470-2045(21)00647-1/abstract
Passeri T, Giammattei L, Le Van T, Abbritti R, Perrier A, Wong J, Bourneix C, Polivka M, Adle-Biassette H, Bernat AL, Masliah-Planchon J, Mandonnet E, Froelich S.Acta Neurochir (Wien). 2022 Jan;164(1):265.
Lien : https://link.springer.com/article/10.1007/s00701-021-05005-9
Voormolen EHJ, Champagne PO, Roca E, Giammattei L, Passeri T, di Russo P, Sanchez MM, Bernat AL, Yoldjian I, Fontanel S, Weill A, Mandonnet E, Froelich S.Neurosurgery. 2021 Jul 15;89(2):308-314.
Link: https: //journals.lww.com/neurosurgery/abstract/2021/08000/intracranial_meningiomas_decrease_in_volume_on.20.aspx
Use of high dose cyproterone acetate and risk of intracranial meningioma in women: cohort study.
Link: https: //www.bmj.com/content/372/bmj.n37.long
Cyproterone acetate and meningioma: a nationwide population-based study.
Champeaux-Depond C, Weller J, Froelich S, Sartor A.J Neurooncol. 2021 Jan;151(2):331-338.Lien : https://link.springer.com/article/10.1007/s11060-020-03672-9
Passeri T, Champagne PO, Bernat AL, Hanakita S, Salle H, Mandonnet E, Froelich S. Acta Neurochir (Wien). 2019 Apr;161(4):761-765.
Lien : https://link.springer.com/article/10.1007/s00701-019-03848-xCombined hormonal influence of cyproterone acetate and nomegestrol acetate on meningioma: a case report.
Champagne PO, Passeri T, Froelich S.Acta Neurochir (Wien). 2019 Mar;161(3):589-592.
Lien : https://link.springer.com/article/10.1007/s00701-018-03782-4
Bernat AL, Bonnin S, Labidi M, Aldahak N, Bresson D, Bouazza S, Froelich S.J Ophthalmic Vis Res. 2018 Jul-Sep;13(3):355-358.
Link: https: //www.ncbi.nlm.nih.gov/pmc/articles/PMC6058554/
Bernat AL, Oyama K, Hamdi S, Mandonnet E, Vexiau D, Pocard M, George B, Froelich S.Acta Neurochir (Wien). 2015 Oct;157(10):1741-6.
Lien : https://link.springer.com/article/10.1007/s00701-015-2532-3
Regression of meningiomas after discontinuation of cyproterone acetate in a transsexual patient.
Cebula H, Pham TQ, Boyer P, Froelich S.Acta Neurochir (Wien). 2010 Nov;152(11):1955-6.
Lien : https://link.springer.com/article/10.1007/s00701-010-0787-2
Does cyproterone acetate promote meningiomatosis, S. Froelich, Q.T. Pham, N. Fontaine, P. Boyer, P. Kehrli, D. Maitrot, J. Auwerx, J.L. Schlienger 56ème Congrès de la Société nationale française de médecine interne(Link to our first abstract in 2007: https: //www.em-consulte.com/article/67674/article/communications-orales I’d also like the PDF of this article to appear by clicking on “Oral communication 083, Page S362”. The pdf is attached.
Does cyproterone acetate promote multiple meningiomas? 10th European Congress of Endocrinology. Sebastien Froelich , Nassim Dali-Youcef , Patrick Boyer , Pierre Kehrli , Daniel Maitrot , Johan Auwerx & , 10th European Congress of Endocrinology
Link: https://www.endocrine-abstracts.org/ea/0016/ea0016p158
Skull base surgery treats lesions deep between the skull base and the brain, or in the skull base itself. The most common pathologies affecting the base of the skull are tumors. These tumors can be histologically “benign” (e.g. meningiomas, acoustic neurinomas, pituitary adenomas, craniopharyngiomas) or malignant (cancerous) (e.g. originating in the sinuses, bone, cartilage, ear or salivary glands).
ESTHESIONEUROBLASTOMA
CHOLESTERINE GRANULOMA
TUMORS OF THE JUGULAR FORAMEN
TUMORS OF THE CAVERNOUS SINUS
ROCK TUMORS
TUMORS OF THE ORBIT
Early diagnosis and multidisciplinary management is the key to effective treatment of these tumors.
Because of their location, injuries to the base of the skull can cause a wide range of symptoms, including visual, hearing, smell, balance and swallowing disorders, headaches, facial asymmetry, sensitivity disorders and/or facial pain, nasal obstruction, vertigo…
Cerebral CT andMRI scans are the main tests used to identify the lesion. CT scans enable precise assessment of bone structures, but lack spatial resolution for soft tissues. MRI enables precise assessment of the soft tissues, the lesion and its relationship with surrounding structures. Other tests may be ordered depending on the type and location of the suspected lesion:
– cerebral angioscan, MRI angiography and/or arteriography to assess the vascularity of the lesion, its relationship with the major vessels supplying the brain, such as the internal carotid and vertebral arteries, and the anatomy of the cerebral drainage veins, in order to preserve them as much as possible,
– an ophthalmological check-up
–an ENT check-up to assess hearing, balance and swallowing skills
–an endocrinological check-up to assess any possible repercussions of the lesion on the functioning of the pituitary gland, a small gland connected to the brain and located at the center of the skull base
etc…
- Operating microscope with integrated neuronavigation and endoscopy
- High-definition (HD) endoscope
- Ultrasonic scalpel
- Neuronavigation
- Intraoperative cranial nerve monitoring
- Intraoperative somaesthetic and motor evoked potentials
- Intraoperative CT scan being acquired
These surgeries are performed in dedicated operating theatres incorporating state-of-the-art imaging, visualization, monitoring and guidance technologies.
The department also boasts highly qualified paramedical staff.
Our common goal is to offer the best possible surgical result with the fewest side effects and maximum preservation of function.
Our department maintains close links with many neurosurgical teams abroad, and we welcome many visiting neurosurgeons from abroad to train in these techniques.