Outlook for grid service technologies within the @neurIST eHealth environment.

The aim of the @neurIST project is to create an IT infrastructure for the management of all processes linked to research, diagnosis and treatment development for complex and multi-factorial diseases. The IT infrastructure will be developed for one such disease, cerebral aneurysm and subarachnoid haemorrhage, but its core technologies will be transferable to meet the needs of other medical areas. Since the IT infrastructure for @neurIST will need to encompass data repositories, computational analysis services and information systems handling multi-scale, multi-modal information at distributed sites, the natural basis for the IT infrastructure is a Grid Service middleware. The project will adopt a service-oriented architecture because it aims to provide a system addressing the needs of medical researchers, clinicians and health care specialists (and their IT providers/systems) and medical supplier/consulting industries.

Interventional spine procedures.

Minimally invasive techniques for the treatment of some spinal diseases are percutaneous treatments, proposed before classic surgery. By using imaging guidance, one can significantly increase accuracy and decrease complication rates. This review report physiopathology and discusses indications, methods, complications and results of performing these techniques on the spine, including different level (cervical, thoracic, lumbar and sacroiliac) and different kind of treatments (nerve block, disc treatment and bone treatment). Finally the present article also reviews current literature on the controversial issues involved.

Magnetic resonance imaging of facial vascular anomalies.

In 36 patients, facial vascular anomalies were studied with 46 magnetic resonance (MR) examinations, 9 angiograms, and 5 computed tomographic scans. All lesions were categorized into classic pathologic groups on the basis of radiologic and pathologic studies, clinical examination, and behavior. Overall, 2 juvenile hemangiomas, 3 capillary malformations (port-wine stains), 18 venous malformations, 9 lymphatic malformations, and 4 arteriovenous malformations were found. MR imaging was superior to computed tomography and angiography for demonstrating the precise anatomic extent of the facial vascular anomalies and their relationship to the adjacent soft tissues but was inferior to computed tomography for demonstrating radiopaque structures such as trophic bone changes and phleboliths. MR imaging was also inferior to angiography in determining the nidus and the exact nature of collateral vascular structures in arteriovenous malformations. MR studies confirmed the clinically suspected diagnosis of facial vascular anomalies and demonstrated typical characteristics for each type of lesion. MR imaging is an ideal initial technique to triage patients with facial vascular anomalies for appropriate management, including observation, endovascular therapy, or surgical excision.

Preoperative silk suture embolization of cerebral and dural arteriovenous malformations.

OBJECT: The aim of this study was to evaluate the use of silk sutures as a medical implant when applied for the embolization of cerebral and dural arteriovenous malformations (AVMs). The facility of surgery and the clinical significance of complications related to preoperative silk suture embolization were evaluated immediately after surgery and at long-term follow up. METHODS: Thirty-four patients harboring 29 cerebral and five dural AVMs underwent embolization in which silk alone or in association with other agents was used. Medical and radiological records obtained in these 34 patients were reviewed retrospectively. The cerebral AVMs were classified according to the Spetzler-Martin grading system and the dural AVMs to the Djindjian grading system. The facility of the resection and the adverse outcomes, including new neurological deficits, hemorrhage, and fever, as well as histopathological evidence of vessel inflammatory changes, were determined in each case. In all 23 surgical cases, the AVM could be easily manipulated and excised. New temporary neurological deficits occurred in three patients. A high Spetzler-Martin grade was not associated with a higher incidence of new neurological deficits. One delayed-onset hemorrhage was detected after embolization. Fever was present in 24% of the patients. No sign of significant vasculitis or perivascular inflammation was found on radiological or histopathological examination. CONCLUSIONS: Silk sutures are safe embolic agents especially for proximal occlusion of AVM feeding vessels. New permanent neurological deficits were not encountered in this series. Fever was considered to be a minor, temporary side effect of silk suture embolization.

Multiple myeloma presenting with external ear canal mass.

The manifestations of multiple myeloma are protean and related to bony osteolytic lesions, and to medullar and renal insufficiency. We report a patient who presented with otalgia as the inaugural symptom of multiple myeloma. Local irradiation combined with systemic chemotherapy led to the disappearance of the temporal bone mass and the accompanying symptoms. To date, 24 months after the diagnosis, the patient is still in remission. The literature on otological involvement in multiple myeloma is reviewed. Symptoms are non-specific and include hearing loss, tinnitus, dizziness, facial paralysis, and otalgia. The diagnosis of multiple myeloma should be considered in the presence of a temporal bone mass.

Diffusion weighted MR imaging on a low-field open magnet. Comparison with findings at 1.5T in 18 patients with cerebral ischemia.

Diffusion-weighted MR imaging (DWI) is particularly sensitive for the detection of acute stoke. Until recently, DWI was performed with EPI technology. We compared 18 patients with clinical suspicion of acute stroke on a standard 1.5T unit and an open low-field MR scanner. Eighteen patients with 20 lesions of acute stroke were studied retrospectively with DWI and ADC mapping on both systems. The technique used was a rotating fast-spin echo T2 at low-field and an EPI sequence at 1.5T. Both examinations were performed within 24 hours and analyzed by two neuroradiologists. We obtained the same results on DWI sequences on both systems, regarding high intensity lesions on DWI. Interpretation of the ADC maps proved to be difficult on low-field MR near the lateral ventricles (3/18). We experienced the same difficulty of interpretation at low and high field in the cerebellum, in the temporal fossa and in cortex situated near bone, due to susceptibility artifacts. Chronic lesions were better visualized at low than at high field. In our opinion, DWI on a low-field open MR scanner is a good technique to evaluate subacute stroke and was as reliable as when performed on a 1.5T MR system.

[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.

Termination of the inferior petrosal sinus: an anatomical variant.

Unusual caudal terminations of the inferior petrosal sinus (IPS) characterized by an extracranial extension joining the internal jugular vein up to 40 mm below the external skull base are reported. This variation was observed bilaterally on an anatomical specimen and unilaterally on four patients during diagnostic cerebral angiography. It may be considered an accessory internal jugular vein and, if present, may allow for an alternate endovascular access to the IPS.

Elevated levels of angiogenic cytokines in the plasma of cancer patients.

Although in the normal healthy organism angiogenesis is a tightly regulated process, under a variety of circumstances it may contribute to disease states. These include the growth of solid tumors, the hematogenous spread of tumor cells and the growth of metastasis. Our aim was to measure the levels of 5 angiogenic cytokines in the plasma of patients with a variety of cancers, to establish a plasmatic angiogenic profile. We prospectively obtained blood samples in citrated tubes from 40 healthy individuals and 75 patients with a variety of solid tumors. Patients who had received any form of treatment in the preceeding 6 months were excluded from the study. Plasma levels of the following 5 cytokines were determined by ELISA: vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), basic fibroblast growth factor, transforming growth factor-beta and tumor necrosis factor-alpha. In some cases, additional samples were taken 4 and 15 days after surgical removal of the tumor. Our findings demonstrate, that firstly, compared to the tumor group VEGF was almost always undetectable or present at very low levels in healthy individuals; secondly, a threshold value for HGF was found to exist between the 2 groups (healthy vs. tumor); and thirdly, there was a clear relationship between plasma levels of VEGF and HGF and extension of disease (i.e., without or with metastases). The timing of blood sampling in the post-operative period was found to be critical, particularly with regard to VEGF and HGF. The existence of a systemic angiogenic profile in the plasma of cancer patients may be useful as a diagnostic and prognostic tool and may help in the future to monitor the responses of individual patients to anti-tumor and, particularly, anti-angiogenic therapy.

Three- to five-dimensional biomedical multisensor imaging for the assessment of neurological (dys) function.

This report describes techniques and protocols implemented at the Geneva Canton University Hospitals (HUG) for the combination of various biomedical imaging modalities and sensors including electromagnetic tomography, to study, assess, and localize neurological (dys) function. The interest for this combination stems from the broad variety of information brought out by (functional) magnetic resonance imaging, magnetic resonance spectroscopy, computed tomography, single-photon emission tomography, positron emission tomography, and electromagnetic tomography. Combining these data allows morphology, metabolism, and function to be studied simultaneously, the complementary nature of the information from these modalities becoming evident when studying pathologies reflected by metabolic or electrophysiologic dysfunctions. Compared with other current multimodality approaches, the one at the HUG is totally compatible with both clinical and research protocols, and efficiently addresses the multidimensional registration and visualization issues. It also smoothly integrates electrophysiology and related data as fully featured modalities.