A new prognostic clinicopathological classification of pituitary adenomas: a multicentric case-control study of 410 patients with 8 years post-operative follow-up.

Pituitary adenomas are currently classified by histological, immunocytochemical and numerous ultrastructural characteristics lacking unequivocal prognostic correlations. We investigated the prognostic value of a new clinicopathological classification with grades based on invasion and proliferation. This retrospective multicentric case-control study comprised 410 patients who had surgery for a pituitary tumour with long-term follow-up. Using pituitary magnetic resonance imaging for diagnosis of cavernous or sphenoid sinus invasion, immunocytochemistry, markers of the cell cycle (Ki-67, mitoses) and p53, tumours were classified according to size (micro, macro and giant), type (PRL, GH, FSH/LH, ACTH and TSH) and grade (grade 1a: non-invasive, 1b: non-invasive and proliferative, 2a: invasive, 2b: invasive and proliferative, and 3: metastatic). The association between patient status at 8-year follow-up and age, sex, and classification was evaluated by two multivariate analyses assessing disease- or recurrence/progression-free status. At 8 years after surgery, 195 patients were disease-free (controls) and 215 patients were not (cases). In 125 of the cases the tumours had recurred or progressed. Analyses of disease-free and recurrence/progression-free status revealed the significant prognostic value (p < 0.001; p < 0.05) of age, tumour type, and grade across all tumour types and for each tumour type. Invasive and proliferative tumours (grade 2b) had a poor prognosis with an increased probability of tumour persistence or progression of 25- or 12-fold, respectively, as compared to non-invasive tumours (grade 1a). This new, easy to use clinicopathological classification of pituitary endocrine tumours has demonstrated its prognostic worth by strongly predicting the probability of post-operative complete remission or tumour progression and so could help clinicians choose the best post-operative therapy.

Anterior screw fixation of type IIB odontoid fractures in octogenarians.

PURPOSE: Type IIB odontoid fractures (OF) in elderly patients are life-threatening conditions. Optimal treatment of these fractures is still controversial. The aim of this study was to assess the clinical and radiological outcome of surgically treated type IIB OF by anterior screw fixation in octogenarians. METHODS: Eleven octogenarians with type IIB OF were operated using anterior screw fixation. Follow-up assessment included operative mortality and morbidity rates, long-term functional outcome and fracture union and stability. RESULTS: There was neither operative mortality nor morbidity. Five patients had excellent clinical outcome, two good outcome, one fair and three poor. Two patients died of unrelated causes 2 months after surgery. Radiographs showed stable bone union in four patients and stable fibrous union in five patients. CONCLUSIONS: Given the results in this short series, we suggest that anterior screw fixation of Type IIB OF may be offered as primary treatment in octogenarians.

Brown-Sequard syndrome revealing intradural thoracic disc herniation.

Brown-Sequard syndrome (BSS) is a rare form of severe myelopathy characterised by a clinical picture reflecting hemisection of the spinal cord. This syndrome is mostly due to a penetrating injury to the spine but many other non-traumatic causes have been described. Intradural thoracic disc herniation (TDH) is one of the rare aetiologies of this syndrome. Despite progress in imaging techniques, diagnosis and treatment remain difficult. We retrospectively reviewed one of the largest reported series of six patients with BSS revealing intradural TDH between 2003 and 2007. There was a marked female predominance and the mean age was 44 years. Before surgery, half of the patients had a severe neurological deficit. The mean duration of symptoms until surgery was 8.5 months (range 0.5-24 months). Spine magnetic resonance imaging (MRI) or spine computer tomography scan showed calcified TDH between T5-T6 and T9-T10. The intradural location of the thoracic herniation was strongly suspected from the clinical data. All the patients underwent posterolateral transpedicular surgery with an operative microscope to open the dura mater. The intradural location of the herniation was overlooked in one case and the patient underwent a second procedure. The dura mater was carefully closed. Two patients' condition worsened immediately after the surgery before slowly improving. All the other patients improved their neurological status immediately after the surgery and at 12 months follow-up. BSS with TDH on the spine MRI scan may be a warning symptom of the intradural location of the herniated disc. In such cases, spine surgeons are advised to use an operative magnification and to open the dura mater to avoid missing this potentially curable cause of severe myelopathy.

[Morphological anatomy of the cranial nerves in their cisternal segment (III-XII)]. / Anatomie morphologique des nerfs crâniens dans leur portion cisternale (du III au XII).

One hundred brains (first injected in cerebral arteries and veins with latex neoprene or India ink and studied under optic magnification) illustrate this anatomic chapter concerning the microsurgical anatomy of the cisternal segment, the neurovascular relationships, and the blood supply of the IIIrd to the XIIth cranial nerves.

[Cranial nerve functional neurosurgery: evaluation of surgical practice]. / La neurochirurgie fonctionnelle des nerfs crâniens Evaluation de l'activité

We report the results of an investigation carried out on the activity of functional neurosurgery of the cranial nerves in the French-speaking countries, based on the analysis of a questionnaire addressed to all the members of the SNCLF. Eighteen centers responded to this questionnaire, which showed that activities and indications varied greatly from one unit to another. The results appear homogeneous and comparable with those reported in the literature. The questionnaire sought to provide a global perspective, open to the comments and questions of all responders on the various techniques raised, with the objective of establishing a common decisional tree for these pathologies and providing if possible to a consensus for better dissemination of these therapies.

Transtemporal-transchoroidal approach and its transamygdala extension to the posterior chiasmatic cistern and diencephalo-mesencephalic lesions.

The aim of this report is to illustrate the successful surgical management of five patients with suprasellar retrochiasmatic and diencephalo-mesencephalic tumours, using a trans-amygdala extension of the trans-temporal/trans-choroidal fissure approach. The procedure is described for five surgically treated patients with such lesions that includes three retrochiasmatic craniopharyngiomas, one hypothalamic hamartoma, and one pilocytic astrocytoma in the left crus cerebri. The management procedure included computed tomography scan (CT scan) and magnetic resonance imaging (MRI). The trans-temporal/trans-choroidal fissure approach enabled us to perform total tumour resection in four patients and a subtotal resection in one. Some technical aspects and pitfalls of the procedure are discussed. This method creates optimum conditions for a radical excision of various suprasellar retrochiasmatic and diencephalo-mesencephalic tumours without mortality and only minimum morbidity. However, no single surgical approach can provide access to the entire variety of tumours located in the suprasellar retrochiasmatic and diencephalo-mesencepalic region. Surgical approaches must be tailored to the site, type of lesion, and its extensions. This method is only another surgical option. Its successful use requires a familiarity with the anatomy of these regions and an understanding of its specificity for a radical excision of some selected tumours, as well as its limitations to access others types of lesions. Although, it seems effective, this approach needs to be evaluated by further experience, owing to the small number of patients reported in this series.

[Subcutaneous metastasis at the operative route of an atypical meningioma of the tentorium. Case report and literature review]. / Métastase sous-cutanée au niveau de la voie d'abord d'un méningiome atypique de la tente du cervelet Cas clinique et revue de la littérature.

Metastatic spreading is a rare complication of meningioma. We report a subcutaneous metastasis from an atypical meningioma of the tentorium. A 69-year-old man presented with a meningioma of the tentorium. The tumor was totally resected. The histological diagnosis was atypical meningioma. The tumor recurred two years later and was irradiated. Despite irradiation, the tumor progressed and was resected three years later. Five months following the second surgery, an isolated subcutaneous mass developed at the skin incision and was resected. The histological examination of the subcutaneous tumor showed histological features of atypical meningioma. Surgery of atypical meningioma carries the risk of iatrogenic metastasis, despite previous irradiation.

[Creation of self-assessment tools for on-line continuing medical education. Modelization of a training session]. / Création d'outils d'autoévaluation pour une formation médicale continue en ligne. Modélisation à propos d'une formation.

BACKGROUND: For several years, the sessions of continuing medical education organized within the framework of the Société française de neurochirurgie have been recorded on the "campus de neurochirurgie" website, accessible in a form called in "videostreaming" which structures the training session. PURPOSE: Using modern educational methods, how can we transform the scientific productions of our meetings into effective tools for on-line continuing education? METHODS: The article describes the experience gained while creating self-assessment tools starting from the teaching material transmitted by the person in charge of a continuing medical education session, selected and an example for demonstration. RESULTS: We present the various written tools for self-assessment: multiple-choice test and script concordance test (SC). These SC were based partly on a clinical case with various test formats: units of diagnosis, investigation and therapeutics. In connection with the example chosen, we propose a model for constructing on-line continuing medical education sessions, which could be used by persons in charge of such training sessions in neurosurgery and in other specialties. CONCLUSIONS: With the availability of on-line self-assessment tests round-tables videostreaming, this teaching method can be used to fulfil mandatory continuing medical education requirements.

[Long-term outcome of the adult onset craniopharyngiomas]. / Devenir à long-terme des craniopharyngiomes de l'adulte.

There is few published series dealing on the long-term outcome of the adult-onset craniopharyngiomas. We report the long term clinical, tomodensitometric and MRI data outcome of 35 (23 woman and 12 men) consecutive adult-onset cured for craniopharyngiomas between 1983 and 2002, and followed-up in Rennes University Hospital. The operation was performed via frontopterional approach in 59% and transphenoïdal approach in 41% of cases. Their age at the time of diagnosis was 44.7+/-15.1 years (21-74). The average postoperation follow-up was 7.4+/-7.0 years (0.1-19.1). Recurrence of tumour occurred in 8 patients (25.8%) and a tumor progression in 1 case. The delay of recurrence after initial surgery was 4.1+/-1.3 years (1.4-6.3). Two patients had 5 and 6 years treatment by growth hormone (GH), without tumor recurrence. The observed increase of weight after the surgical cure of craniopharyngiomas concerned 22 patients (63%). The average weight gain was 17.5+/-14.7 kg (1.5-58). In 7 cases (20%) neuropsychological disorders were noted, of which 2 with lost of professional activity. Three patients died. In conclusion the craniopharyngiomas recurrence is frequent and can appear in very prolonged deadlines after the initial surgery.

MR imaging features of spinal schwannomas and meningiomas.

Spinal schwannomas and meningiomas are mostly benign, intra-dural extramedullary tumours. We retrospectively reviewed the Magnetic Resonance Imaging (MRI) examinations of 52 spinal schwannomas and meningiomas operated on at our institution since 1998. The series included 28 schwannomas and 24 meningiomas. We compared MRI features of schwannomas and meningiomas and evaluated statistical features that would allow differentiation. Tumours with extraspinal extension were excluded. Concerning the cranio-caudal distribution, half of the cervical tumours were schwannomas, 72% of thoracic lesions were meningiomas and all lumbar tumours were schwannomas. Meningiomas were significantly located at the upper and mid thoracic levels and schwannomas in the lumbar area. On T1-weighted images, MRI signal intensity and heterogeneity were not statistically different between meningiomas and schwannomas. On T2-weighted images, the signal intensity appeared significantly hyperintense and heterogeneous for schwannomas. After Gd-DTPA, we observed a significant difference between meningiomas and schwannomas, the enhancement being intense and heterogeneous in cases of schwannomas, and moderate and homogeneous in cases of meningiomas. The last significant qualitative item was the "dural tail sign", a dural enhancement or thickening near the tumour. It was found in only 16 cases of meningiomas. A simple diagnostic test was built for schwannomas by processing a multiple agreement analysis with the 6 significant items: cranio-caudal location, T2 signal intensity, T2 signal heterogeneity, Gd-DTPA enhancement intensity and heterogeneity, and the "dural tail sign". This test allowed diagnosis of schwannomas with a sensitivity of 96.4%, a specificity of 83.3%, a positive predictive value of 87.1%, and a negative predictive value of 95.7%. In conclusion, we consider that a diagnosis of schwannoma should be made when a spinal intradural extramedullary tumour shows hyperintensity on T2W images or intense enhancement without dural tail sign; otherwise meningioma is more probable.

Acute nontraumatic spinal subdural hematomas in three patients.

STUDY DESIGN: The clinical data, magnetic resonance imaging, intraoperative findings, and functional outcome were reviewed for three patients under anticoagulant therapy who experienced acute nontraumatic spinal subdural hematoma. OBJECTIVES: To draw attention to this rare complication of anticoagulant therapy and to assess the magnetic resonance findings and clinical outcome of patients with spinal subdural hematoma after surgical evacuation. SUMMARY OF BACKGROUND DATA: Among intraspinal hematomas, spinal subdural hematomas are by far the least common. Magnetic resonance findings have been demonstrated in only a few cases of spinal subdural hematomas. The timing of the operation and the anatomic location of the hematoma essentially determine the functional outcome. METHODS: Three case reports of spinal subdural hematomas in patients receiving anticoagulant therapy are presented. Particular interest was given to the clinical and magnetic resonance data, the intraoperative findings, and the functional outcome. RESULTS: The three patients each had a complete preoperative neurologic deficit. Sagittal T1- and T2-weighted magnetic resonance images of the spine proved to have high sensitivity for defining the type of bleeding and delineating the craniocaudal extension of the hematoma. Surgical evacuation was performed within 26 hours after the onset of symptoms. Intraoperative findings showed the hematoma to be confined between the dura and the arachnoid in two patients, and to be associated with rupture into the subarachnoid space in one patient. Postoperative recovery was incomplete in two patients, and did not improve in the remaining patient. CONCLUSIONS: Spinal subdural hematoma must be considered in patients under anticoagulant therapy with spontaneous signs of acute spinal cord or cauda equina compression. Magnetic resonance imaging with sagittal T1- and T2-weighted images were adequate and reliable for diagnosis of spinal subdural hematoma. On the basis of previous studies and the authors' intraoperative findings, spinal subdural hematomas could be viewed as spinal dural border hematomas. The level of preoperative neurologic deficit seemed to be critical for recovery despite prompt surgical evacuation.

Anterior screw fixation of odontoid fractures.

BACKGROUND: Anterior screw fixation is the best treatment for odontoid fractures when the fracture line is horizontal or oblique downward and backward, as it preserves atlantoaxial mobility, especially axial rotation. Some details regarding patient positioning and operative technique need to be stressed to obtain the best results and avoid complications. METHODS: Between 1989 and 1997, we treated 17 cases of odontoid fracture by anterior screw fixation. Only two patients presented with motor neurologic deficit. Fracture line was horizontal in 3 cases and oblique downward and backward in 14 cases. RESULTS: Adequate reduction and fixation was obtained in all cases except one, where posterior displacement of the screw occurred without neurologic complications. Functional result was satisfactory in all cases except two, where we noted significant limitation of cervical rotation. CONCLUSION: Successful anterior screw fixation gives the best anatomical and functional results for odontoid fractures. Correct installation is very important for operative success.

Sensitivity of auditory brainstem response in acoustic neuroma screening.

Auditory brainstem response (ABR) is the reference screening technique for acoustic neuromas, but because of a few false negatives and the increasing performance of magnetic resonance imaging (MRI), its role as the standard method has been questioned. We assessed sensitivity of screening tests in 89 patients with surgically proven acoustic neuromas. Sensitivity of ABR was 92%; 94% for extracanalicular neuromas and 77% for intracanalicular neuromas. For stapedius reflex (SR), sensitivity was 84% and for caloric vestibular response (CVR) 86%. The combined sensitivity of ABR + SR was 97% and of ABR + RS + CVR 98%. For false negatives, the greatest diameter including the intracanalicular portion was always less than 18 mm, with a mean of 15 mm, and none of these tumours reached the brainstem. For patients with unilateral cochleo-vestibular deficit, we propose ABR and SR as first-line screening tests. These tests are repeated at 6 months and at 1 year in the case of normal results. MRI is ordered for patients whose auditory threshold is too low and for those whose ABR or SR results favour retrocochlear disease.

Pituitary adenomas with infra-sellar extension into the nasopharynx.

Three cases of pituitary adenomas with infra-sellar extension into the nasopharynx and the nasal cavities are reported. The clinical signs were epistaxis, nasal obstruction, painful sinuses and purulent rhinorrhoea. The initial diagnostic hypothesis was that of a carcinoma of the nasopharynx or the sinuses in all three cases. The diagnosis was made by histological examination and measurement of plasma hormone levels. These cases highlight the difficulty in the diagnosis of such tumours due to their misleading clinical, radiological and histological features.

Spontaneous chronic spinal epidural hematoma of the lumbar spine.

We report an exceptional description of a spontaneous chronic spinal epidural hematoma presenting as lumbar radiculitis. The computed tomographic, magnetic resonance imaging, and intraoperative findings are presented. We discuss anatomical and pathophysiological considerations that could lead to such a condition. We estimate that spontaneous spinal epidural hematomas located in the ventral space are in fact premembranous or posterior longitudinal ligament hematomas.

[Diabetes insipidus caused by metastasis to the hypothalamo-hypophyseal axis. Apropos of 4 cases]. / Diabète insipide par métastase de l'axe hypothalamo-hypophysaire. A propos de 4 cas.

This study concerns the cases of 4 patients with polyuria and polydipsia syndrome as part of a known evolutive neoplasia. MRI demonstrated an intra- and supersellar tumoral process developed from the pituitary stalk and the posterior pituitary lobe suggesting metastasis.

MR demonstration of spontaneous acute spinal subdural hematoma.

We report an unusual case of spontaneous acute spinal subdural hematoma. To date, only a few cases of magnetic resonance imaging (MRI) demonstration of such a pathology have been reported in the medical literature. We analyse the pathogenesis, clinical presentation, magnetic resonance imaging results, intraoperative findings and prognosis of this rare condition. We would like to stress that prompt and non-invasive diagnosis by MRI sagittal sections leads to efficient surgical treatment.

Contribution of MRI to the diagnosis of ACTH-secreting pituitary adenomas. Exploration of 9 patients with Cushing's disease.

Between June 1987 and October 1989, nine patients with suspected Cushing's disease were explored by magnetic resonance imaging (MRI), using an 0.35 or 0.5 Tesla magnet. All these patients underwent transsphenoidal surgery and radio-surgical correlations could be established. MRI showed a lesion in 5 cases; it was negative in 2 cases and doubtful in 2 cases. Surgery was positive for pituitary adenoma in 7 cases and negative in 2 cases (including 1 patient with subsequently discovered paraneoplastic syndrome). Using sagittal and coronal planes and combined with gadolinium enhancement, MRI proved to be the most sensitive and specific of all exploratory methods for the diagnosis of ACTH-secreting pituitary adenomas.

Contribution of MRI to the diagnosis and post-therapeutic monitoring of brain stem tumours.

MRI has become indispensable to the positive diagnosis of brain stem tumours which develop preferentially in young people. The prognosis of these tumours, especially infiltrating gliomas, being relatively sombre, it is important to make a precise morphological diagnosis of the lesions (increase in size, signal abnormalities) which will help both neurosurgeons and radiotherapists. As regards post-therapeutic monitoring, MRI with gadolinium contrast injection is harmless and will make it possible to follow these patients regularly and to detect recurrences.

Rathke's cleft cysts: surgical-MRI correlation in 16 symptomatic cases.

Rathke's cleft cysts (RCCs) are non neoplastic epithelial lesions of the sellar region that have been rarely reported as a clinical entity. We retrospectively reviewed the magnetic resonance imaging (MRI), intraoperative, and pathological findings of a series of 16 cases of RCCs operated at our institution since 1992. Concurrently, we discussed the different hypotheses about their embryological origin. The patients included 12 females and 4 males, 11 to 73 years of age. Endocrine disturbance was the most common presentation, followed by headaches and visual impairment. The location of the cyst was intrasellar in 7 cases, intrasellar and suprasellar in 6 cases, and suprasellar in 3 cases. The size of the cyst ranged from 8 to 26 mm (mean 12 mm). MRI signal intensity was quite variable on T1-weighted images. The cyst appeared hyperintense in 6 cases, hypointense in 6 cases, isointence in 3 cases, and heterogeneous in one case. On T2-weighted images (available in 13 cases), the signal intensity was more constant and appeared hyperintense in 11 cases and hypointense in 2 cases. After Gd-DTPA, we did not observe enhancement either of the cyst contents or of the cyst wall, but only of the pituitary gland in all patient. Most often, the pituitary gland was displaced inferiorly by the cyst located above showing a typical image of "an egg in a cup". Fifteen patients were operated upon via the transsphenoidal approach and one upon a frontal craniotomy. Intraoperatively, the cyst contents were gelatinous or thick, and dark colored. In 2 cases, it was cerebrospinal fluid-like corresponding to the signal observed on MRI. The position of the pituitary gland confirmed by surgery in 15 cases coincided with enhancement seen and MR imaging. In 13 cases where biopsy of the cyst wall was performed, it confirmed focally ciliated columnar or cuboid epithelium. A coexistent adenoma was found in one case. In conclusion, we consider that RCCs have varied MRI characteristics so that no pathognomonic sign may be observed. Except in few cases, there were no correlation between MRI and intraoperative findings. Therefore, even with MRI studies, differential diagnoses with others cystic lesions of the sellar region remains extremely difficult. The most interesting findings on MRI studies of RCCs were to locate the pituitary gland to help the surgeon to preserve pituitary tissue during surgery.