Search

Byline: K. Wolf (1), E. C. Kirsch (2), L. Sponagel (1), D. A. Rufenacht (3), M. Battegay (1) Keywords: Key Words HIV; Arteriovenous malformation; Antiretroviral therapy Abstract: HIV infection or complications of HIV-induced immunodeficiency may affect the central nervous system (CNS). However, vascular cerebral pathologies are very rare, in particular intracerebral arteriovenous malformations (AVM). We report the case of an HIV-infected patient who had a cerebral AVM leading to symptoms such as recurring focal seizures. Only after initiation of potent antiretroviral combination therapy, but not antiretroviral monotherapy or bitherapy, could the viral load be suppressed and immunodeficiency resolved. Two years after the start of highly active antiretroviral therapy (HAART) total occlusion of the AVM could be demonstrated. Taken together, this case report may demonstrate the potent angiogenic activity of HIV for AVM. Also, this case report might show that inhibition of such a cofactor may lead to resolution of an AVM. Author Affiliation: (1) Basel Center for HIV Research, Outpatient Dept. of Internal Medicine, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland Phone (+41/61) 265-5072, Fax: -4604, e-mail: mbattegay@uhbs.ch, CH (2) Neuroradiology, Dept. of Radiology, University Hospital Basel, Switzerland, CH (3) Neuroradiology-HUG, University Hospital Geneva, Switzerland, CH Article note: Received: June 15, 2001 * Revision accepted: December 3, 2001

Background: Giant cavernous carotid aneurysms (GCCAs) usually exert substantial mass effect on adjacent intracavernous cranial nerves. Since predictors of cranial nerve deficits (CNDs) in patients with GCCA are unknown, we designed a study to identify associations between CND and GCCA morphology and the location of mass effect.Methods: This study was based on data from the prospective clinical and imaging databases of the Giant Intracranial Aneurysm Registry. We used magnetic resonance imaging and digital subtraction angiography to examine GCCA volume, presence of partial thrombosis (PT), GCCA origins, and the location of mass effect. We also documented whether CND was present.Results: We included 36 GCCA in 34 patients, which had been entered into the registry by eight participating centers between January 2009 and March 2016. The prevalence of CND was 69.4%, with one CND in 41.7% and more than one in 27.5%. The prevalence of PT was 33.3%. The aneurysm origin was most frequently located at the anterior genu (52.8%). The prevalence of CND did not differ between aneurysm origins (p = 0.29). Intracavernous mass effect was lateral in 58.3%, mixed medial/lateral in 27.8%, and purely medial in 13.9%. CND occurred significantly more often in GCCA with lateral (81.0%) or mixed medial/lateral (70.0%) mass effect than in GCCA with medial mass effect (20.0%; p = 0.03). After adjusting our data for the effects of the location of mass effect, we found no association between the prevalence of CND and aneurysm volume (odds ratio (OR) 1.30 (0.98-1.71); p = 0.07), the occurrence of PT (OR 0.64 (0.07-5.73); p = 0.69), or patient age (OR 1.02 (95% CI 0.95-1.09); p = 0.59).Conclusions: Distinguishing between medial versus lateral location of mass effect may be more helpful than measuring aneurysm volumes or examining aneurysm thrombosis in understanding why some patients with GCCA present with CND while others do not.Clinical trial registration no.: NCT02066493 (clinicaltrials.gov) [ABSTRACT FROM AUTHOR]

Spinal magnetic resonance angiography (MRA) is difficult to perform because of the size of the spinal cord vessels. High-field MR improves resolution and imaging speed. We examined 17 patients with spinal vascular diseases with dynamic contrast-enhanced three-dimensional MR sequences. In three patients, the artery of Adamkievicz could be seen; we could also detect all arteriovenous malformations and dural fistulas. MRA has the potential to replace diagnostic spinal angiography and the latter should be used only for therapeutic purposes. [ABSTRACT FROM AUTHOR]

Goals Of Work: Bone pain and functional impairment are major concerns for multiple myeloma (MM) patients. The goal of this study was to better define the role of percutaneous cementoplasty (PC) in improving their quality of life.Materials and Methods: This retrospective analysis included 28 consecutive heavily pretreated MM patients managed at our institution between 1996 and 2002. They underwent a total of 34 PC procedures for the treatment of 117 vertebrae and 2 iliac sites and were evaluated at 1 month.Main Results: Significant pain reduction of >50% was obtained after 83% of the procedures, with a mean visual analogous score decreasing from 7.48/10 to 2.1/10 (p < 0.001). It resulted in a complete interruption of opiate analgesic consumption after 59.3% of the procedures, with a mean decrease of 70.4% in the opiate dose. Functional impairment was evaluated with the Eastern Cooperative Oncology Group (ECOG) performance status scale, with mean scores improving from 1.9 to 0.86 after the procedures (p = 0.001). There was no major complication.Conclusion: PC is a safe, feasible, and efficient approach for the treatment of bone pain and disability in MM patients. [ABSTRACT FROM AUTHOR]

Background and Purpose: The purpose of this study was to assess the initial post-market experience of the device and how it is compared with the Penumbra Pivotal trial used to support the 510k application., Methods: A retrospective case review of 157 consecutive patients treated with the Penumbra system at seven international centers was performed. Primary endpoints were revascularization of the target vessel (TIMI score of 2 or 3), good functional outcome as defined by a modified Rankin scale (mRS) score of ≤2 and incidence of procedural serious adverse events. Results were compared with those of the Penumbra pivotal trial., Results: A total of 157 vessels were treated. Mean baseline values at enrollment were: age 65 years, NIHSS score 16. After use of the Penumbra system, 87% of the treated vessels were revascularized to TIMI 2 (54%) or 3 (33%) as compared with 82% reported in the Pivotal trial. Nine procedural serious adverse events were reported in 157 patients (5.7%). All-cause mortality was 20% (32/157), and 41% had a mRS of ≤2 at 90-day follow-up as compared with only 25% in the Pivotal trial. Patients who were successfully revascularized by the Penumbra system had significantly better outcomes than those who were not., Conclusion: Initial post-market experience of the Penumbra system revealed that the revascularization rate and safety profile of the device are comparable to those reported in the Pivotal trial. However, the proportion of patients who had good functional outcome was higher than expected., Competing Interests: Competing interests: None., (© 2010, Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

This paper presents a method leveraging coded motion information to obtain a fast, high quality motion field estimation. The method is inspired by a recent trend followed by a number of top-performing optical flow estimation schemes that first estimate a sparse set of features between two frames, and then use an edge-preserving interpolation scheme (EPIC) to obtain a piecewise-smooth motion field that respects moving object boundaries. In order to skip the time-consuming estimation of features, we propose to directly derive motion seeds from decoded HEVC block motion; we call the resulting scheme "HEVCEPIC". We propose motion seed weighting strategies that account for the fact that some motion seeds are less reliable than others. Experiments on a large variety of challenging sequences and various bit-rates show that HEVC-EPIC runs significantly faster than EPIC flow, while producing motion fields that have a slightly lower average endpoint error (A-EPE). HEVC-EPIC opens the door of seamlessly integrating HEVC motion into video analysis and enhancement tasks. When employed as input to a framerate upsampling scheme, the average Y-PSNR of the interpolated frames using HEVC-EPIC motion slightly outperforms EPIC flow across the tested bit-rates, while running an order of magnitude faster.

Existing video coders anchor motion fields at frames that are to be predicted. In this paper, we demonstrate how changing the anchoring of motion fields to reference frames has some important advantages over conventional anchoring. We work with piecewise-smooth motion fields, and use breakpoints to signal discontinuities at moving object boundaries. We show how discontinuity information can be used to resolve double mappings arising when motion is warped from reference to target frames. We present an analytical model that allows to determine weights for texture, motion, and breakpoints to guide the rate-allocation for scalable encoding. Compared with the conventional way of anchoring motion fields, the proposed scheme requires fewer bits for the coding of motion; furthermore, the reconstructed video frames contain fewer ghosting artefacts. The experimental results show the superior performance compared with the traditional anchoring, and demonstrate the high scalability attributes of the proposed method.

Object: The underlying mechanisms causing intracranial perianeurysmal edema (PAE) are still poorly understood. Since PAE is most frequently observed in giant intracranial aneurysms (GIAs), the authors designed a study to examine the occurrence of PAE in relation to the location, size, and partial thrombosis (PT) of GIAs along with the clinical impact of PAE., Methods: Magnetic resonance imaging data for patients with a diagnosis of unruptured GIA from the international multicenter Giant Intracranial Aneurysm Registry were retrospectively analyzed with regard to location and size of the GIA, PAE volume, and the presence of PT. The occurrence of PAE was correlated to clinical findings., Results: Imaging data for 69 GIAs were eligible for inclusion in this study. Perianeurysmal edema was observed in 33.3% of all cases, with the highest frequency in GIAs of the middle cerebral artery (MCA; 68.8%) and the lowest frequency in GIAs of the cavernous internal carotid artery (ICA; 0.0%). Independent predictors of PAE formation were GIA volume (OR 1.13, p = 0.02) and the occurrence of PT (OR 9.84, p = 0.04). Giant intracranial aneurysm location did not predict PAE occurrence. Giant aneurysms with PAE were larger than GIAs without PAE (p < 0.01), and GIA volume correlated with PAE volume (rs = 0.51, p = 0.01). Perianeurysmal edema had no influence on the modified Rankin Scale score (p = 0.30 or the occurrence of aphasia (p = 0.61) or hemiparesis (p = 0.82)., Conclusions: Perianeurysmal edema was associated with GIA size and the presence of PT. As no PAE was observed in cavernous ICA aneurysms, even though they exerted mass effect on the brain and also displayed PT, the dura mater may serve as a barrier protecting the brain from PAE formation.

Background and Purpose: According to the International Study of Unruptured Intracranial Aneurysms (ISUIA), anterior circulation (AC) aneurysms of <7 mm in diameter have a minimal risk of rupture. It is general experience, however, that anterior communicating artery (AcoA) aneurysms are frequent and mostly rupture at <7 mm. The aim of the study was to assess whether AcoA aneurysms behave differently from other AC aneurysms., Methods: Information about 932 patients newly diagnosed with intracranial aneurysms between November 1, 2006, and March 31, 2012, including aneurysm status at diagnosis, its location, size, and risk factors, was collected during the multicenter @neurIST project. For each location or location and size subgroup, the odds ratio (OR) of aneurysms being ruptured at diagnosis was calculated., Results: The OR for aneurysms to be discovered ruptured was significantly higher for AcoA (OR, 3.5 [95% confidence interval, 2.6-4.5]) and posterior circulation (OR, 2.6 [95% confidence interval, 2.1-3.3]) than for AC excluding AcoA (OR, 0.5 [95% confidence interval, 0.4-0.6]). Although a threshold of 7 mm has been suggested by ISUIA as a threshold for aggressive treatment, AcoA aneurysms <7 mm were more frequently found ruptured (OR, 2.0 [95% confidence interval, 1.3-3.0]) than AC aneurysms of 7 to 12 mm diameter as defined in ISUIA., Conclusions: We found that AC aneurysms are not a homogenous group. Aneurysms between 4 and 7 mm located in AcoA or distal anterior cerebral artery present similar rupture odds to posterior circulation aneurysms. Intervention should be recommended for this high-risk lesion group.

Background and Purpose: Major cerebral thromboembolism often resists recanalization with currently available techniques. The authors present their initial experience with a self-expanding stent for use in intracranial vascular reconstruction, permitting immediate recanalization of acute thromboembolic occlusions of the anterior circulation., Patients and Methods: Patients treated with the Cordis Enterprise™ self-expanding intracranial stent system for acute thromboembolic occlusion of the major anterior cerebral arteries were included. Treatment comprised systemic and intraarterial thrombolysis, mechanical thrombectomy, and stent placement. Stent deployment, recanalization rate by means of Thrombolysis In Cerebral Infarction (TICI) scores and the clinical outcome were all assessed., Results: Six patients presenting with acute carotid T (n = 2) or proximal middle cerebral artery occlusion (n = 4) were treated. The mean National Institutes of Health Stroke Scale (NIHSS) score at presentation was 14; the mean age was 57 years. Successful stent deployment and immediate recanalization were achieved in all six with a TICI score of ≥ 2. Neither distal emboli nor any procedure-related complications were encountered. One patient developed symptomatic intracerebral hemorrhage and two patients needed decompressive craniectomy after treatment. The mean NIHSS score at 10 days was 10, but only one patient showed a complete recovery at 3 months., Conclusion: Intracranial placement of the Enterprise™ self-expanding stent has proven to be feasible and efficient in achieving immediate recanalization of occluded main cerebral arteries. The use of antiplatelet therapy after treatment may, however, increase the risk of reperfusion intracerebral hemorrhage.

We developed a method to produce tubular in vitro models of the cerebral vessels from real patient data. Three-dimensional data sets obtained from patients undergoing rotational angiography were used for stereolithographic biomodeling by using rapid prototyping technology. In a second step, tubular reproductions of the cerebral vessels were obtained by using the lost-wax technique. These reproductions can be useful for hemodynamic research and for the development and preclinical evaluation of new endovascular treatment methods.