Perfusional deficit and the dynamics of cerebral edemas in experimental traumatic brain injury using perfusion and diffusion-weighted magnetic resonance imaging.

The aim of this work was to characterize edema dynamics, cerebral blood volume, and flow alterations in an experimental model of brain trauma using quantitative diffusion and perfusion magnetic resonance imaging (MRI). Associated with an influx of water in the intracellular space 1-5 h post-trauma as demonstrated by the 40% reduction in apparent diffusion coefficient, a 70-80% reduction in cerebral blood flow was measured within the lesioned region. Transient hypoperfusion (40-50%) was also observed in the non-traumatized contralateral hemisphere, although there was no evidence of edema formation. After the initial cytotoxic edema, a clear evolution toward extracellular water accumulation was observed, demonstrated by an increase in apparent diffusion coefficient.

Dynamics of cerebral edema and the apparent diffusion coefficient of water changes in patients with severe traumatic brain injury. A prospective MRI study.

The distinction between intracellular (ICE) and extracellular edema (ECE) has a crucial prognostic and therapeutic importance in patients with severe traumatic brain injury (STBI). Indeed, ICE usually leads to cellular death, and maintenance of a cerebral perfusion pressure (CPP) above 70 mmHg is still under debate since this practice may increase ECE. The purpose of this study was to describe the ECE and ICE kinetics associated with STBI using quantitative diffusion MRI. Twelve patients were prospectively studied. The initial ADC in ICE measured on day 1.3+/-0.7 is significantly reduced compared to normal-appearing parenchyma (0.51+/-0.12 * 10(-3) mm2/s vs. 0.76+/-0.03 * 10(-3) mm2/s, n=12, P<0.0001) and reaches normality on MRI 3 performed on day 14.2+/-3.3. In patients presenting an extension of ICE on MRI 2 performed on day 6.7+/-1.4 (ADC(MRI2)=0.40+/-0.11 * 10(-3) mm2/s), ADC values in the extension area at the first MRI were slightly, but not significantly reduced compared to normal parenchyma (0.69+/-0.05 * 10(-3) mm2/s, P=0.29). Normalization occurred equally by day 14. ADC in ECE (1.34+/-0.22 * 10(-3) mm2/s) was elevated and stable with time under CPP therapy. Therefore, ECE is not worsened by CCP therapy, and ICE appears more relevant than ECE in STBI.

A multicenter study of 705 ruptured intracranial aneurysms treated with Guglielmi detachable coils.

BACKGROUND AND PURPOSE: The long-term durability of Guglielmi detachable coil (GDC) embolization of cerebral aneurysms is still unknown. The purpose of this study was to evaluate the stability of anatomic occlusion of aneurysms treated with GDCs and assess the rate of recanalization and re-treatment. METHODS: A multicenter study involving 650 patients with 705 ruptured aneurysms treated with GDCs between January 1998 to May 2003 was conducted. During this period, 63% of ruptured aneurysms were treated by the endovascular technique. The morbidity and mortality associated with this technique, procedural feasibility, acute angiographic occlusion results, and long-term angiographic follow-up were assessed. RESULTS: Overall technical feasibility of GDC treatment was 96.9%. Upon admission, 25% of patients were Hunt and Hess grade IV or V. Acute angiographic results in 683 aneurysms demonstrated total occlusion in 496 cases (72.6%), subtotal occlusion in 171 cases (25.%), and incomplete occlusion in 16 cases (2.4%). All patients were controlled by angiography and MR imaging at 3 months, 1 year, and subsequent yearly examinations post-treatment. A second treatment was performed in 27 cases (recanalization, 4.7%). Long-term follow-up angiograms (mean, 36 months) were obtained in 571 aneurysms (95%). Of them, 422 aneurysms (73.9%) demonstrated complete occlusion, 148 aneurysms (25.9%) demonstrated subtotal occlusion, and only 1 aneurysm was incompletely occluded. Overall mortality was 11.4% for all patients, with procedural mortality evaluated at 1.4%. Overall morbidity was calculated at 8.6%. Only one rebleeding occurred in our study, with a second procedure performed without vital consequences for the patient. CONCLUSION: Our multicenter study confirms the stability of aneurysm embolization with GDC, with only 4.7% of aneurysms requiring re-treatment.

Clinical results of an open prospective study of a bis-GMA composite in percutaneous vertebral augmentation.

In this open prospective trial, 53 patients with acute pain from osteoporotic vertebral fracture related to osteoporosis or malignancy underwent vertebral augmentation with a new bisphenol-a-glycidyl dimethacrylate (bis-GMA) resin (Cortoss, Orthovita, Malvern, Pa, USA). Treatment consisted of up to 8 ml of Cortoss injected into a given vertebra. The procedure encompassed single and multiple injections (including the contralateral hemivertebra, to a maximum of 3 vertebral levels). Follow-up was at 4 and 8 days and at 1, 3, and 6 months. The primary efficacy end point was patient-rated pain using a 100-point visual analog scale (VAS, with 100 as severest pain) on day 4 following treatment; secondary end points were analgesic use and quality-of-life and disability scores from the Oswestry Disability Index (ODI) and a short-form 12-item questionnaire (SF-12). The present report contains interim results collected up to the 1-month post-treatment time point. At baseline, the group's mean VAS score was 69, indicating moderate to severe pain; at day 4, 32 of 53 patients (60.4%) reported a 30% or greater reduction in baseline pain accompanied by a VAS pain score less than 50 (mean 38.1). Pain reduction was maintained at 1 month (mean VAS 31.3). The average ODI score at baseline was 55, suggesting significant disability among participants prior to Cortoss treatment. Following treatment, the ODI scores were significantly reduced from these baseline levels (day 8, 47.4; 1 month, 33.6). Further, SF-12 physical and mental component scores at 1 month after treatment increased from baseline by 26% and 11%, respectively; while analgesic use decreased concomitantly, primarily among patients with underlying osteoporosis. A total of 20 adverse events were deemed to be device-related. The most frequent clinically significant adverse events attributed to Cortoss were leakage of Cortoss from within the vertebral body at placement (12%), back pain (7%), and unspecified pain (7%). These results indicate that vertebral augmentation with Cortoss rapidly reduces pain, decreases disability, and improves physical functioning in patients with painful vertebral compression fractures.

Ruptured aneurysm on a double origin of the posterior inferior cerebellar artery: a pathological entity in an anatomical variation. Report of two cases and review of the literature.

The posterior inferior cerebellar artery (PICA) is known to be very variable, and some of its anatomical variations can explain ischemic complications that occur during endovascular treatment of aneurysms. The authors report two cases of anatomical variation of the PICA that they have called its double origin, one of which gave rise to an aneurysm. The first patient was a 36-year-old man who presented with a subarachnoid hemorrhage related to the rupture of a PICA aneurysm. The aneurysm was treated by the endovascular route. Selective and superselective studies showed that the PICA origin was low on the fourth segment of the vertebral artery (VA). The aneurysm was located on an anastomosis between the PICA and a small upper arterial branch originating from the VA. Embolization was performed through the small branch with no problem, but a lateral medullary infarct followed, probably due to occlusion of the perforating vessels. The same anatomical variation was incidentally discovered in the second patient. To the authors' knowledge, neither this anatomical variation of the PICA nor the aneurysm's topography have been previously described angiographically. This highlights the role of angiography in pretreatment evaluation of aneurysms especially when perforating vessels or small accessory branches that are poorly visualized on angiographic studies are concerned, as in the territory of the PICA. Anatomy is sometimes unpredictable, and the surgeon must be very careful when confronted with these variations because they are potentially dangerous for endovascular treatment.