Changed cervical kinematics after fusion surgery.

PURPOSE: Analyzing and comparing the range of motion and movement pattern of subjects who underwent an anterior cervical fusion using trabecular metal with control subjects. METHODS: Three-dimensional kinematics of planar active axial rotation and active lateral bending of 50 experimental and 41 control subjects were registered by means of an electromagnetic tracking system. RESULTS: Comparing the experimental group with the control group reveals that the range of the main motion component differs significantly (p < 0.01) during the active axial rotation and lateral bending movement. During active axial rotation, the coupled lateral bending motion component also differs between both groups. The root mean square value of the jerkiness (derivative of the acceleration) and de deviation from the 6-polynomial smoothed function of the main as well as the coupled motion component express the qualitative aspects of kinematics and are significantly different between the experimental and the control group for both movements (p < 0.05). CONCLUSIONS: Subjects who have an anterior cervical fusion with trabecular metal show significant quantitative as well as qualitative differences in cervical kinematics during active axial rotation and lateral bending compared to control subjects.

[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.

Comparison of the effect of anterior and posterior neurosurgical treatment for cervical spondylotic myelopathy: a clinical outcome.

Cervical degenerative disease is the most common cause of acquired disability in patients over the age of 50. The incidence of cervical spondylotic myelopathy (CSM) is increasing with aging of the population. Surgical decompression is indicated for severe CSM. There is, however, insufficient evidence to prefer anterior over posterior surgical decompression technique for CSM. Our purpose was to identify groups of patients that would benefit from a chosen surgical approach with a better clinical outcome. We conducted a retrospective analysis of patients operated for CSM between 2007 and 2011. Patients were assessed according to the Nurick grading system. Preoperative and postoperative clinical details and MR imaging were analyzed. Treatment consisted of either anterior cervical discectomy with fusion (ACDF) or laminectomy without fusion. Over a period of 4 years, 90 patients were included. The mean age of patients was 64.5 ± 1.3 years. Of 90 included patients, 42 patients were treated with ACDF and 48 with laminectomy. Mean total Nurick grade recovery rate (NGRR) was 29.6% with 31.2% in ACDF and 27.7% in laminectomy. Mid-sagittal diameter of the cervical canal measured on MRI-T2 increased significantly more with laminectomy (4.4 mm) than ACDF (2.2 mm) (p < 0.001). The presence of preoperative spasticity or quadriparesis or a multilevel compression indicated a higher recovery on the Nurick scale. Surgical treatment of CSM leads to a significant improvement of the functional neurological status of the patient as well as an increase in the diameter of the cervical canal. No significant difference in Nurick recovery was found between ACDF and laminectomy indicating that clinical decision-making in our series was adequate. We were able to demonstrate that even severely disabled patients have a good chance of neurologic recovery after surgical treatment for CSM.

[A century of intracranial aneurysm treatment: from carotid ligation to endovascular procedures]. / De la ligature de carotide aux techniques endovasculaires ou un siècle de traitement des anévrismes intracrâniens. Historique du traitement des anévrismes.

Intracranial aneurysm treatment began in the 20th century. Treatment remained anecdotal for a long time because these lesions could not be visualized. This was the period of hunterian ligation of the carotid and trapping. After the discovery of the carotid angiography at the end of the 1920s, a new direct clipping approach started. Other techniques were used, such as wrapping and coating. Finally, in the 1980s, endovascular procedures appeared and are now in constant progress. The advantages, problems and improvements of these treatments are briefly reviewed.

Assessment of the uncertainties in dose delivery of a commercial system for linac-based stereotactic radiosurgery.

PURPOSE: Linac-based stereotactic radiosurgery (SRS) was introduced in our department in 1992, and since then, more than 200 patients have been treated with this method. An in-house-developed algorithm for target localization and dose calculation has recently been replaced with a commercially available system. In this study, both systems have been compared, and positional accuracy, as well as dose calculation, have been verified experimentally. METHODS AND MATERIALS: The in-house-developed software for target localization and dose calculation is an extension to George Sherouse's GRATIS(R) software for radiotherapy treatment planning, and has been replaced by a commercial (BrainSCAN version 3.1; BrainLAB, Germany) treatment planning system (TPS) for SRS. The positional accuracy for the entire SRS procedure (from image acquisition to treatment) has been investigated by treatment of simulated targets in the form of 0.2-cm lead beads inserted into an anthropomorphic phantom. Both dose calculation algorithms have been verified against manual calculations (based on basic beam data and CT data from phantom and patients), and measurements with the anthropomorphic phantom applying ionization chamber, thermoluminescent detectors, and radiographic film. This analysis has been performed on a variety of experimental situations, starting with static beams and simple one-arc treatments, to more complex and clinical relevant applications. Finally, 11 patients have been evaluated with both TPS in parallel for comparison and continuity of clinical experience. RESULTS: Phantom studies evaluating the entire SRS procedure have shown that a target, localized by CT, can be irradiated with a positional accuracy of 0.08 cm in any direction with 95% confidence. Neglecting the influence of dose perturbation when the beam passes through bone tissue or air cavities, the calculated dose values obtained from both TPSs agreed within 1% (SD 1%) for phantom and patient studies. The application of a one-dimensional path length correction for tissue heterogeneity influences the treatment prescription 4% on average (SD 1%), which is in compliance with theoretical predictions. The phantom measurements confirmed the predicted dose at isocenter within uncertainty for the different treatment schedules in this study. CONCLUSION: The full SRS procedure applied to an anthropomorphic phantom has been used as a comprehensive method to assess the uncertainties involved in dose delivery and target positioning. The results obtained with both TPSs are in agreement with AAPM Report 54, TG 42 and clinical continuity is assured. However, the use of a one-dimensional path length correction will result in an increase of 4% in dose prescription, which is slightly more than that predicted in the literature.

Expression of IL-6 mRNA in normal rat and human pituitaries and in human pituitary adenomas.

Cells expressing IL-6 mRNA were detected by in situ hybridization in normal pituitaries. In normal untreated rat pituitary the expression was very low. Within hours after IP administration of liposaccharide, IL-6 mRNA accumulated in the anterior lobe of the pituitary. Production of IL-6 was monitored after dissociation and culture of pituitary cells. High levels (8000 pg/ml) were recovered after 72 hr in culture. In normal human pituitaries, less than 1% of cells expressed IL-6 mRNA or IL-6 receptor mRNA (IL-6-R mRNA). In gonadotropinomas, prolactinomas, and non-functioning adenomas, only rare, scattered positive cells were found for either IL-6 or IL-6-R. In contrast, both genes were highly expressed in ACTH- and GH-secreting tumors at the junction of adenoma and infiltrating fibrous tissue and around blood vessels. The combined expression of IL-6 and IL-6-R suggests that IL-6 acts in an autocrine or in a paracrine way in ACTH and GH adenomas.

Expression of pituitary adenylate cyclase activating polypeptide and receptors in human brain tumors.

The capacity of brain tumor samples to synthesize pituitary adenylate cyclase activating polypeptide (PACAP) was evaluated by the reverse transcriptase-polymerase chain reaction technique (RT-PCR). The expression of PACAP receptors was assessed by a combination of RT-PCR techniques, conventional binding techniques, and also by the ability of PACAP to stimulate adenylate cyclase activity. A weak PACAP mRNA and PACAP receptor mRNA expression was detected in only 3 of 16 meningiomas. A weak PACAP-stimulated adenylate cyclase activity (+20%) was detected in 10 of the 16 samples but binding of labeled PACAP was never observed. In the 16 gliomas studied (including two oligodendrogliomas and two ependymomas), PACAP mRNA was identified in 13 samples and PACAP receptor mRNA in 15 samples. PACAP receptors were identified in all the samples by binding studies and/or by PACAP stimulation of the adenylate cyclase activity. PACAP mRNA was never detected in pituitary adenomas (three prolactinomas, two mixed PRL-GH-producing tumors, three GH-secreting tumors, three gonadotrophinomas, one ACTH-producing tumor, two nonsecreting tumors) whereas PACAP receptor mRNA was highly expressed in all the tumors except prolactinomas, where it was at the limit of detection, confirming the binding and adenylate cyclase activation results. Thus, it is unlikely that the neuropeptide PACAP could influence meningioma's cell growth; PACAP secreted from extratumoral areas may influence pituitary tumors and PACAP could participate to gliomas development.

Identification of a new chromogranin B fragment (314-365) in endocrine tumors.

A rabbit antiserum was raised against the fragment (350-365) of human chromogranin B corresponding to the C-terminal end of a putative proteolytic fragment generated by the cleavage of a dibasic doublet located in position 366-367 of the precursor. A radioimmunoassay was developed. Chromatographic analysis of 10 endocrine tumor extracts (one liver metastasis of a gastrinoma, one liver metastasis of a medullary carcinoma of the thyroid, one VIPoma, one insulinoma, one nonsecreting pancreatic endocrine tumor, one local recurrence of a gut carcinoid, two pituitary gonadotropinoma, and two non-secreting pituitary adenomas) revealed the presence of two forms of immunoreactive material. The most abundant form had an apparent molecular weight of 4500 and was purified to homogeneity by successive reverse-phase HPLC chromatographies and partially sequenced. The N-terminal sequence of the peptide, established by automated Edman degradation, was A-S-E-E-E-P-E-Y-G-E-E-I-K-G-Y-P-V-Q and corresponded to the 314-332 sequence of human chromogranin B. Taking into account the specificity of the antiserum used for peptide identification, we deduced that the purified peptide was chromogranin B(314-365) and represented a new form generated by limited proteolysis of chromogranin B.

Solitary dorsal intramedullary schwannoma. Case report.

A case of solitary dorsal intramedullary schwannoma diagnosed by magnetic resonance imaging and treated surgically is reported. The authors review the previously published cases. The possible etiology of the tumor as well as some difficulties encountered in the diagnostic procedure and treatment are discussed.

Pituitary microadenomas: diagnosis with dynamic serial CT, conventional CT and T1-weighted MR imaging before and after injection of gadolinium.

PURPOSE: The few studies comparing CT and MR in the diagnosis of pituitary microadenomas give discordant results. This prospective study compares the value of dynamic serial CT (DSCT), conventional CT (CCT), pre-Gd T1-weighted spin echo (T1SE-Gd) and post-Gd T1-weighted SE (T1SE+Gd) in the detection of pituitary microadenomas. METHODS: The value of CT and MR was assessed in 17 cases, with the surgical confirmation as reference. The CTs and MRs were independently and blindly evaluated by two neuroradiologists. Because the finding at MR and/or CT influenced the selection of patients for surgery, the positive predictive value was calculated. The sensitivity calculation applies only for a specific group of postsurgical patients with positive CT and/or MR (marked with an asterisk for these reasons). RESULTS: In this study, the highest sensitivity* (88% and 82%, respectively, for observers I and II) was achieved by DSCT. The T1SE-Gd and T1SE+Gd (evaluated separately) were slightly inferior (sensitivity* of 76% for observer I). The combination of T1SE-Gd with T1SE+Gd improved the sensitivity* to 94% and 82% respectively, for observers I and II. There was also moderate improvement of sensitivity* by combination of DSCT with conventional CT (94% for observer I). CONCLUSION: These results suggest that rapid injection of a large amount of contrast conjointly with a fast scanning through the pituitary is crucial for the confident detection of microprolactinomas. Taking into account the similar results of the combination DSCT + CT and T1SE-Gd + T1SE+Gd in the detection of microprolactinomas, high field MRI is the first step modality in the evaluation of presumed hypophyseal hyperprolactinemia.

Combined cesarean section and clipping of a ruptured cerebral aneurysm: a case report.

We present a case of subarachnoid hemorrhage due to a ruptured cerebral aneurysm of the right internal carotid artery in a patient at 34 weeks of gestation (G2P1). A combined surgical procedure (cesarean section followed by clipping of the aneurysm) was performed with good maternal and fetal outcome. The differential diagnosis, the timing of neurosurgery, and the anesthetic techniques used are discussed.

Sudden hypotonic paraparesis caused by tophaceous gout of the lumbar spine.

Gouty arthritis of the axial skeleton is rare, and neurological complications due to spinal cord or nerve root compression secondary to tophaceous deposits have been seldom reported. We describe a patient with chronic gouty arthritis who developed an acute paraparesis caused by tophaceous cauda equina compression. Surgical removal of the mass resulted in complete recovery.

Spinal arachnoiditis mimicking a spinal cord tumor: a case report and review of the literature.

We report on an unusual case of idiopathic arachnoiditis mimicking a spinal cord tumor in a 50-year-old man with progressive paraparesis. The medical imaging work-up showed an enlarged terminal cone with adjacent cysts. Although there was no enhancement of the terminal cone or the surrounding structures, the diagnosis of spinal cord tumor was maintained and surgery was carried out. Exploration of the cauda equina and the tissue surrounding the terminal cone did not reveal a tumor. The patient improved dramatically after surgery but the symptoms recurred 1 year later. We review arachnoiditis, its pathology, and its treatment with special attention drawn to the primary form of spinal arachnoiditis.

Thoracic spinal epidural cysts.

Two cases of spinal cord compression by thoracic epidural cysts are reported. The first case, associated with a lipoma, is of a congenital type, while the second illustrates a rare mechanism of spinal cord compression caused by a post-traumatic cyst after stretching of the brachial plexus and tearing of the meningeal sheaths of nerve roots. Computed tomography of the spine is helpful in disclosing the cyst and associated malformation, particularly in congenital cases. The prognosis is good after removing the cyst and closing the fistula communicating with the subarachnoid space. Further surgical treatment may be required in complex congenital malformations.

Cortical stimulation for central neuropathic pain: 3-D surface MRI for easy determination of the motor cortex.

Motor cortex electric stimulation has been reported to be effective for the treatment of central post-stroke pain and trigeminal neuropathic pain. Five patients with pain due to injury of the trigeminal nerve and with abnormalities of facial sensibility, as well as two patients suffering of a post-stroke thalamic pain, were subjected to stimulation applied epidurally on the motor cortex. Quadripolar electrodes were implanted under local anaesthesia and the precise location of the motor cortex was determined on three-dimensional surface MRI the day prior to surgery. In our experience, correct topographic localization of the electrode on the motor cortex seems to be crucial to obtain pain reduction.

[3-year evaluation of the surgical treatment of intracranial aneurysms. Apropos of 100 surgically treated aneurysms]. / Bilan de trois ans de traitement chirurgical des anévrysmes intracrâniens. A propos de 100 anévrysmes opérés.

The authors present the results of surgical treatment of a consecutive series of 100 cases of intra cranial aneurysm. The results are analysed in relation to various factors such as the pre-operative delay, the clinical status, the location of the aneurysm and the age of the patient. Altogether, the percentage of excellent and good results is 83%. Bad results account for 10% of the total and deaths represent 7%. Shunted postoperative hydrocephalus was recorded in 10% of cases and half were due to aneurysm of the anterior communicating artery. Postoperative spasm (16%) was the severest complication, responsible for more than half the deaths.

[Pseudo-Hakim-Adams syndrome. Neuropsychological study of 23 cases of misdiagnosed Hakim-Adams syndrome]. / Pseudo-syndrome de Hakim et Adams. Etude neuropsychologique de 23 cas de faux diagnostic de syndrome de Hakim et Adams.

The authors study the characteristics of a group of 23 patients for whom an initial tentative diagnosis of Hakim-Adams syndrome (H-A syndrome) was eventually rejected. On account of several factors distinguishing these patients from the true H-A group, the authors propose using the term "pseudo Hakim-Adams syndrome". The distinguishing factors include: the grounds for admission, i.e. mental or mnesic deterioration, associated with radiological images of ventricular dilatation; a clinical picture dominated by mental disorders with only rare disorders of gait and sphincter control (several neurological defects were direct consequences of previous cerebral disease); no antecedents of spontaneous meningeal hemorrhage or meningitis in the case history; neuropsychological examination showing fewer disorders of concentration and less dyscalculia and constructive dyspraxia than in true HA, and far more atypical signs of the aphasic and anxio-depressive type. The authors think that various pathological processes may be responsible for this pseudo H-A syndrome in which a predominant mental picture is associated with ventricular dilatation.

[Indications and operative conditions of aneurysms in old patients (author's transl)]. / Les indications et les conditions opératoires des anévrysmes chez les gens âgés. A propos de trois cas.

The age factor is analysed for the operative indication in old patients. For the authors, operative indications are depended of mental and general status, clinical grade (I or II), localization and anatomical conformation of the aneurysm. The operation is performed only if the patient is asymptomatic or three weeks after the onset of the subarachnoid hemorrage. The peroperative hypotension is prohibited.

Meningioma of the fourth ventricle presenting with intermittent behaviour disorders: a case report and review of the literature.

Intraventricular meningiomas are rare, representing 0.5-5% of all intracranial meningiomas. They arise mostly within the lateral ventricles and more rarely in the third ventricle. Meningiomas of the fourth ventricle are exceptional. They are clearly defined as meningiomas arising from the choroid plexus and lying strictly within the fourth ventricle. We report a 76 year old male patient presenting with a 2-week history of headache and cognitive disorders with agitation and restlessness particularly exacerbated at night or when lying down. CT scan and MR imaging showed a contrast-enhancing lesion located purely within the whole fourth ventricle, with slight ventricular enlargement. At surgery, we totally removed a well-vascularised, greyish encapsulated mass attached to the choroid plexus. Pathological examination revealed a WHO grade I fibroblastic meningioma. We reviewed the literature concerning this unusual meningioma location.

[Diagnostic and microsurgical aspects of brachial plexus tumors]. / Aspects diagnostiques et microchirurgicaux des tumeurs du plexus brachial.

Brachial plexus tumors are rare. Important progress in the diagnosis of these tumors has been realized, by means of CT-scan and angiography. The nature of the tumour, benign or malignant, plays a determining part in the results. Microsurgical technique allows large excisions with minimal sequelae.