Imaging features in combined atlantoaxial and occipitoatlantal rotatory subluxation: a rare entity. Case report.

The authors report a new case of combined atlantoaxial and occipitoatlantal rotatory subluxation in a 17-year-old girl. They describe the clinical and imaging features of this rare entity. An occiput-C2 arthrodesis was performed.

Spontaneous vertex extradural hematoma: considerations about causes. Case report and review of the literature.

A 36-year-old woman with an uneventful medical history was admitted to the emergency department following an initial generalized seizure. Neuroimaging workup disclosed a homogeneous mass at the vertex, which first was diagnosed as vertex meningioma. Anticonvulsant drug therapy was administered and the patient was discharged. Two months later the patient was examined in our neurosurgery department for additional therapeutic recommendations. A repeated neuroimaging examination showed considerable regression of the lesion. The findings on magnetic resonance imaging were consistent with those of a regressing extradural hematoma (EDH). A complete blood-coagulation study displayed no evidence of abnormality. Thorough questioning of the patient revealed no history of pericranial infection or head trauma occurring within the last 2 years. The final diagnosis was spontaneously occurring vertex EDH. In this report the authors describe the clinical and neuroimaging features of the case as well as the management strategy, and discuss etiological aspects within the context of a careful review of the literature.

Stereotactic radiosurgery for trigeminal neuralgia: a multiinstitutional study using the gamma unit.

A multiinstitutional study was conducted to evaluate the technique, dose-selection parameters, and results of gamma knife stereotactic radiosurgery in the management of trigeminal neuralgia. Fifty patients at five centers underwent radio-surgery performed with a single 4-mm isocenter targeted at the nerve root entry zone. Thirty-two patients had undergone prior surgery, and the mean number of procedures that had been performed was 2.8 (range 1-7). The target dose of the radiosurgery used in the current study varied from 60 to 90 Gy. The median follow-up period after radiosurgery was 18 months (range 11-36 months). Twenty-nine patients (58%) responded with excellent control (pain free), 18 (36%) obtained good control (50%-90% relief), and three (6%) experienced treatment failure. The median time to pain relief was 1 month (range 1 day-6.7 months). Responses remained consistent for up to 3 years postradiosurgery in all cases except three (6%) in which the patients had pain recurrence at 5, 7, and 10 months. At 2 years, 54% of patients were pain free and 88% had 50% to 100% relief. A maximum radiosurgical dose of 70 Gy or greater was associated with a significantly greater chance of complete pain relief (72% vs. 9%, p = 0.0003). Three patients (6%) developed increased facial paresthesia after radiosurgery, which resolved totally in one case and improved in another. No patient developed other deficits or deafferentation pain. The proximal trigeminal nerve and root entry zone, which is well defined on magnetic resonance imaging, is an appropriate anatomical target for radiosurgery. Radiosurgery using the gamma unit is an additional effective surgical approach for the management of medically or surgically refractory trigeminal neuralgia. A longer-term follow-up review is warranted.

Selective use of ultrasonography for acute appendicitis in children.

BACKGROUND: To evaluate the role of ultrasonography in children with equivocal signs of acute appendicitis, and correlate with initial clinical impression and pathological findings. METHODS: This is a prospective evaluation of all children presenting with a possible diagnosis of appendicitis during a 14-month study period. Patients with unequivocal clinical signs of appendicitis underwent appendectomy without ultrasonography. Patients with equivocal signs had documentation of the clinical impression and subsequent abdominal ultrasound. Statistical analysis of results was performed using the chi-square test (P <0.05 significant). RESULTS: Two hundred fifteen consecutive children were enrolled. Signs were unequivocal in 116 and equivocal in 99. Seven patients in the first group had a normal appendix at operation. Of the 99 patients with equivocal signs, there were 28 true positives, 3 false positives, 64 true negatives, and 4 false negatives. In equivocal cases, sensitivity of the initial clinical impression versus ultrasound was 50% and 88%, respectively (P <0.05). Specificity was 85% and 96%, respectively. The positive and negative predictive values improved from 63% to 90% and 78% to 94%, respectively, with the use of ultrasonography. CONCLUSIONS: The low false positive rate (6%) in clinically obvious cases of appendicitis does not, in our opinion, warrant ultrasonography. In clinically equivocal cases, ultrasonography is a fast, sensitive, and specific diagnostic modality to diagnose or rule out appendicitis, avoiding the need for prolonged observation and/or hospitalization.

[Psychological and behavioral disorders with good outcome in neurosarcoidosis]. / Troubles psychocomportementaux d'évolution favorable au cours d'une neurosarcoïdose.

INTRODUCTION: Neurological involvement is observed in 5% of cases of sarcoidosis and includes impairment of the central nervous system, the meninges, and the cranial and peripheral nerves. Besides neurological defects, cognitive impairment may be encountered ranging from isolated memory defect to dementia. EXEGESIS: We report a case of neurosarcoidosis occurring in a 40-year-old woman, a native of Reunion Island, with initial meningeal and hypophyseal involvement. Three years later, while treated with low dose prednisolone and methotrexate, she presented a paranoid state associated with cognitive impairment of frontal type and severe behavioral disturbances. After 2 years of high dose steroid treatment associated with hydroxychloroquine, her behavioral status improved, allowing social and familial reinsertion. CONCLUSION: In our observation, sarcoidosis was revealed through a central neurological impairment, with chronic meningitis, facial nerve palsy, and, finally, through psychiatric symptoms and severe behavioral disturbances. A slow favorable outcome was obtained using high dose methylprednisolone and hydroxychloroquine with total regression of behavioral disturbances but with persisting cognitive alteration.

[Scanner in a medical emergency test of the nervous system]. / Contribution du scanner à l'examen des urgences médicales du système nerveux.

Computed tomography is the essential examination in patients with severe manifestations of neurological disorders. We discuss emergency situations involving the central nervous system due to vascular and infections lesions. Trauma and acute complications of brain tumours, usually seen within a neurosurgical context, are not discussed here.

[Treatment of choroid melanoma by Gamma-Knife radiosurgery]. / Traitement du mélanome choroïdien par radiochirurgie Gamma-Knife.

Conservative treatment of uveal melanomas by Gamma Knife Radiosurgery is based on the use of cross fire technique with 201 Cobalt60 sources. A following of 13 months is available for the first case operated by Gamma-Knife Surgery in France. Technical baselines and one year preliminary results are reported. The diagnosis of uveal melanoma T3NOMO was established by converging results of clinical examination, angiography and echography. The definition of the target was based on stereotactic MRT examination. We delivered a dose of 50 Gys to the marginal isodose (50%). Today, one year after treatment the tumor decreased, the visual function was preserved. There were no side effect or complication.

[Atlanto-axial lateral mass osteoarthritis. Three case reports and review of the literature]. / Arthrose atloïdo-axoïdienne unilatérale. A propos de 3 cas et revue de la littérature.

This report describes three cases of symptomatic unilateral C1-C2 mass osteoarthritis. The patients were all female aged 67, 62 and 59 years. One patient had a history of rheumatoid arthritis. Unilateral occipital pain was the main symptom. Neuroradiological work-up included open mouth anteroposterior radiograph, flexion/extension lateral radiograph of the cervical spine, CT scan with coronal and sagittal reconstruction and MRI. Findings allowed differential diagnosis with tumoral or infectious disease of upper cervical spine and ruled out C1-C2 instability. CT scan and MRI permitted precise operative planning by determining the course of vertebral artery in the C1 and C2 vertebrae. Two patients were treated by CT scan guided steroid injection. The third patient was treated by C1-C2 arthodesis after failure of conservative treatment.

[Advances in the contributions of imaging to stereotaxic localization of cerebral arteriovenous malformations for radiosurgery ]. / Evolution des données d'imagerie dans le repérage stéréotaxique pour la radiochirurgie des malformations artério-veineuses cérébrales.

Historically, angiography was one of the first diagnostic methods to allow for visualization of neurovascular structures. It has been and still is very useful for precise evaluation of vascular pathology and is one of the main elements in treatment planning for radiosurgical targets. It is the only imaging method that gives insight into the angioarchitecture of a cerebral arteriovenous malformation, possibly reducing the target volume. Construction of frames (Leksell, Fisher) that are compatible with cross-sectional imaging methods, such as CT and MRI allowed there use for planning of stereotactical treatment for brain cerebral arteriovenous malformations. The advantages of these methods are given by the fact, that they are less invasive and that they allow visualization of neurovascular structures and surrounding cerebral structures. Further evolution of the cross-sectional imaging techniques allowed reconstruction of the image data in different planes and segmentation of structures such as vessels. Use of special algorithms allow visualization of the image data, i.e. surface rendering with 3D images of vascular structures. However, such images allow no detailed insight into the angioarchitecture of a cerebral arteriovenous malformation and give rather a view of the whole volume, i.e. a "tumor" aspect of the cerebral arteriovenous malformation. Similar images are currently also obtained with digital substraction angiography using rotational image acquisitions and image postprocessing allowing 3D reconstruction of angiographical image data. The different image evaluation methods are thus complementary all giving useful information for treatment planning. Therefore it would be useful to develop the possibility to integrate the information obtained by these modalities. Image fusion require identification of fiducial marks, what can be performed with application of external marks or by using internal anatomical marks. Recent developments allow now use of vascular structures as fidiucial marks to obtain image fusion. This paper reports on the evolution of stereotactical planning, performed on 541 patients over a period of eight years.

[Intracranial aneurysm revealed by panhypopituitarism. Considerations on therapeutic management based on a case report and review of the literature]. / Anévrysme intra-crânien révélé par un panhypopituitarisme. Considérations sur la prise en charge thérapeutique à propos d'un cas et revue de la littératue.

We report a case of an unruptured intracranial aneurysm in paraclinoidal location which was a unmasked by severe panhypopituitarism. An ipsilateral internal carotid artery (ICA) clamp test was performed in the pretreatment stage. The test was well tolerated and the aneurysm could be embolized with GDC (Guglielmi detachable coils) without necessitating an occlusion of the ICA. The postoperative course was uneventful and the patient was discharged after 48 hours. At one year, cerebral angiograms confirmed complete obliteration of the aneurysm. Therapeutic management of this rare entity is discussed along with a careful and exhaustive review of the literature.

[Craniopharyngioma in children: MRI study of 43 cases]. / Les crAniopharyngiomes de l'enfant.

BACKGROUND AND PURPOSE: Craniopharyngiomas are intra-cranial tumors, relatively frequent in children, expanding in the pituitary stalk axis, from the third ventricle to the sphenoid body. Plain films and CT scan generally show a calcified lesion, deforming the sella turcica. MRI improves tumor description and topographic and structural analysis of the lesion. The aim of this study is to analyze the MRI aspect of craniopharyngiomas in a pediatric population and to correlate findings with surgical data. METHODS: MR and CT studies of 43 pediatric cases of histology-proven craniopharyngiomas were reviewed retrospectively. Tumor emergence, extensions and signal on different sequences were recorded. We searched for radio-surgical correlations. RESULTS: Craniopharyngiomas can be classified into two groups: intra-sellar tumors and third ventricle floor tumors (infundibulum and tuber cinereum). Preferential routes of extension are observed in each group correlated with consistency (cystic and/or solid). Surgical data confirmed these results. CONCLUSIONS: MRI is crucial for the pre-therapeutic evaluation of craniopharyngiomas allowing not only a detailed description of the tumor but also guiding therapeutic decisions. This series demonstrated that craniopharyngiomas exhibit two different types of localization and behavior. Embryonic development of the tumor explains the topographical differences.

[A retrospective study of 32 lumbar synovial cysts. Clinical aspect and surgical management]. / Kystes synoviaux lombaires: aspects cliniques et prise en charge chirurgicale. Etude rétrospective de 32 cas.

We report a retrospective analysis of a series of 32 cases of lumbar synovial cysts. Clinically, two populations were identified: patients who presented radicular pain mimicking the clinical diagnosis of disk herniation (group I) and patients who presented neurogenic claudication consistent with a diagnosis of lumbar spinal stenosis (group II). The radiological work-up consisted in standard X-rays and CT-scan for all patients. MRI (magnetic resonance imaging) was performed in 14 patients. All the patients were operated on. The surgical technique consisted in foraminotomy for patients in group I and more or less extensive laminectomy for patients in group II. Functional outcome was marked by a significant improvement in 96.9% of the patients and those who presented a motor deficit recovered in 83% of the cases. Based on the findings in this series, we discuss the clinical aspects and the therapeutic management of this pathological entity.

The role of Gamma Knife radiosurgery in the treatment of pineal parenchymal tumours.

OBJECT: The aim of this study was to document the possible role of Gamma Knife radiosurgery, suitable for the treatment of deep and well limited tumors, in the management of pineal parenchymal tumors (PPT). POPULATION AND METHODS: We reviewed retrospectively a series of 13 patients with PPT treated by Gamma Knife radiosurgery during 16 procedures. Mean age was 31 (range 10 to 74). Eight patients had pineocytomas (61.5%), and 5 had pineoblastomas (38.5%). Radiosurgery was performed alone in 6 cases, after partial microsurgical resection in 3 cases, in association with chemotherapy in 3 cases and following conventional fractionated radiotherapy in 1 case. The marginal dose to these tumors ranged from 11 to 20 Gy (mean 15 Gy). RESULTS: With a mean follow-up of 34 months (range 6 to 88), all tumors responded to treatment and disappeared or ceased growing. Two patients with pineoblastoma had tumor size progression out of the initial target requiring several radiosurgery procedures. At the end of the follow-up period, 10 out of 12 patients were alive. Two patients with pineoblastoma died because of carcinomatous meningitis or tumor size progression. We observed no mortality or major morbidity related to radiosurgery. CONCLUSION: This study confirms that radiosurgery can be an effective and safe primary treatment modality for patients with pineocytomas. It should have a role in multimodality therapy which includes microsurgical resection, fractionated radiotherapy and chemotherapy for the management of malignant pineal tumors.

Retrospective study of 77 patients harbouring lumbar synovial cysts: functional and neurological outcome.

BACKGROUND: Synovial cysts represent an uncommon and probably underestimated pathological entity of the degenerative lumbar spine. The authors report a retrospective analysis of the clinical presentation, radiological studies and operative findings in 77 patients surgically treated for symptomatic lumbar synovial cysts at their institution. MATERIALS AND METHOD: Between January 1992 and June 1998, a total of 77 patients presenting with symptomatic lumbar synovial cysts were operated on in the author's department. Operative procedure, complications, results and pathological findings were correlated with preoperative assessment. There were 41 men and 36 women with an average age of 63 years (range 44-90 years). RESULTS: On the basis of their symptom complex on presentation, two populations were identified: patients who presented with a single radicular pain (group I = 51 patients), and patients who presented with bilateral neurogenic claudication (group II = 26 patients). Neurological examination on presentation demonstrated motor deficit (12%), sensory loss (26%) and reflex changes (35%). Degenerative disc disease and facet joint osteoarthritis was a frequent finding in patients with pre-operative MRI. Facet joint orientation was >45 degrees in 76.6% of patients. Preoperative spondylolisthesis was found in 48% on radiological studies. All the patients were treated surgically with resection of the cyst. No fusion was performed as a first line procedure. However subsequent fusion was necessary in one patient who developed symptomatic spondylolisthesis. Mean follow-up period was of 45 months ranging from 18 to 105 months. Only one recurrence occurred during the follow-up period. An excellent or good functional outcome was seen in 97.4% of cases, and 89% of the patients with motor deficit recovered. CONCLUSIONS: Surgical resection of lumbar synovial cysts is an effective treatment associated with very low morbidity. Synovial cysts are associated with increased grade and frequency of facet joint asteoarthritis but not with increased grade or frequency of degenerative disc disease compared with patients without cysts. In the author's opinion, at the present time, there is no reliable criterion which allows the development of a symptomatic spinal instability to be predicted in patients with a preoperative spondylolisthesis and therefore fusion as a first line procedure is still debatable.

Schizencephaly: correlation between the lobar topography of the cleft(s) and absence of the septum pellucidum.

The bipolar defects observed in schizencephalies-clefts in the hemispheric mantle on the one hand, absent septum pellucidum on the other--without any anatomic or functional continuity suggest that there is some sort of common specific vulnerability of both structures. A study of the correlation between lobar location of the clefts and involvement of the septum pellucidum was undertaken, considering the hypothesis that the septum pellucidum is the portion of a "medial medullary velum" that corresponds to the frontal lobe, while the psalterium would correspond to the parieto-occipital lobe and the fimbria corresponds to the temporal lobe. This retrospective study of 16 cases of schizencephaly properly investigated by MR discloses a perfect correlation, all cases with absent septum pellucidum having clefts into the frontal lobe, all cases with present septum pellucidum having clefts in the parietal, temporal, and occipital lobes, and only the few instances (3 cases) of overlapping findings being characterized by clefts in the central area, where the distinction between posterior frontal and anterior parietal lobes is uncertain because of the cortical dysplasia related to the clefts. Partial defects of the septum also proved to correlate closely, topographically, with the location of the clefts. Therefore, the facts confirm a segmental organization of the mantle and septal defects, suggesting a developmental rather than a destructive mechanism, which could at least be related to a segmental pattern of selective vulnerability.

Postoperative intracranial thrombolysis and angioplasty.

SUMMARY: The case study involves a patient presenting middle cerebral artery thrombosis, related to a severe vasospasm following subarachnoid hemorrhage due to aneurysm rupture. The patient was treated initially by surgical clipping of the left middle cerebral artery aneurysm. After surgery, the neurological status of the patient was normal. Six days later, the patient presented right hemiplegia and aphasia that were related to the proximal left middle cerebral artery thrombosis. Despite recent open-skull surgery, in situ thrombolysis using urokinase and antip late let antibodies (abciximab) was performed. The thrombosed artery was reopened and a severe vasospasm was observed. The vasospasm was treated by transluminal angioplasty. No intracranial hemorrhage was noted after thrombolysis and angioplasty, whereas subcutaneous hemorrhage around the scalp incision was observed. The patient recovered from motor and language impairment. The only long-term symptom was a mild dysorthographia. Balance of risk/benefit is discussed for such aggressive thrombolytic therapy. In this particular case, effectiveness and uneventful use of abciximab was demonstrated despite very recent brain surgery that was considered a formal contra-indication for the use of such a powerful thrombolytic drug. Vessel thrombosis is an exceptional complication of cerebral vasospasm. In the early hours, intra-arterial thrombolysis may be considered, but recent intracranial surgery is usually an exclusion criterion to performing thrombolysis. We report the case of a patient who underwent thrombolysis and angioplasty in the postoperative period to treat this complication of vasospasm.

MRI of intracranial chordomas. Extent of tumour and contrast enhancement: criteria for differential diagnosis.

We present six proven cases of chordoma of the clivus studied by CT and MRI, with special attention to the extent of the tumour and to the signal intensity after intravenous gadolinium. MRI is the best technique for assessing the extent of the tumour but CT is important for showing osteolysis. Our aim was to determine differential diagnostic neuroradiological criteria. Reliable signs of chordoma of the skull base are: posterior extension to the pontine cistern; a lobulated, "honeycomb" appearance after gadolinium: the swollen appearance of the bone in the early stages; bone erosion on CT and frequent extension to critical structures such as the circle of Willis, cavernous sinuses and brain stem.

Normal galenic drainage of the deep cerebral venous system in two cases of vein of Galen aneurysmal malformation.

INTRODUCTION: Vein of Galen aneurysmal malformations (VGAM) are assumed to be related to the persistence of the embryonic median prosencephalic vein of Markowski, which does not involute in cases of VGAM and becomes the venous collector of the shunt, characteristic of the malformation. The arterial feeders of VGAMs are all primitive meningeal arteries present during the embryonic period of the constitution of the malformation. It has also been assumed that the internal cerebral veins were absent in patients presenting with VGAM. There is no clear evidence indicating, however, that the deep venous structures cannot develop normally. CASE REPORTS: We report on two cases of VGAM in which superselective retrograde transvenous catheterization and MRI demonstrated that normal internal cerebral veins were draining into the aneurysmal vein of Galen. CONCLUSIONS: It is conceivable that, as in our patients, this drainage pattern is only angiographically detectable via selective retrograde transvenous drainage. The possibility of such normal deep galenic venous drainage must be considered in VGAM management, as it may imply occurrence of adverse effects when the malformation is occluded on the venous side.

Effect of the Gamma Knife on trigeminal neuralgia.

The Gamma Knife radiosurgical treatment of 20 patients suffering from trigeminal neuralgia is reported. Eleven patients received radiosurgical treatment with the goal of pain relief. Six had secondary trigeminal neuralgia due to AVM, large cavernous sinus and petrous bone meningiomas, trigeminal neurinoma, or chordoma; 5 others had essential trigeminal neuralgia. Radiosurgical treatment was considered only after the failure of conventional medical and surgical treatment. For the other 9 patients, the control of the tumor was the main objective (four acoustic and one trigeminal neurinoma, one petroclival chordoma, and three tumors of the cavernous sinus: one hemangiopericytoma, one metastasis, one meningioma). We have not been using this method for sufficient time to evaluate long-term results. However, we believe that a large majority of our patients benefited greatly from this technique with a rapid clinical improvement, which is a reflection of the relevance of the chosen target.