ABSTRACT
Original instrumental setups embedded in industrial-type multi-diamond-wire sawing equipment are presented for in situ measurements of the apparent wire diameter, the vertical force applied to the wire web, and the wire-web bow during the cutting of crystalline silicon bricks into wafers. The proportionality relationship between the vertical force and the wire bow during the cut of a Czochralski silicon brick is, for the first time, experimentally observed as expected by the theoretical calculations. As a result, the in situ bow measurement is shown to provide a direct control of the cutting efficiency, which is inversely proportional to the vertical force. In addition, the wire-wear evolution during successive cuts is analyzed using the in situ measurement of the apparent wire diameter together with the in situ bow measurements for equivalent cutting conditions using several bow sensors distributed above the wire web. The three-dimensional plot of the cutting efficiency resulting from the bow measurement processing gives access to the distribution of the cutting efficiency along the wire web during the progress of the cut. Given the homogeneous properties of the silicon material used, the cutting efficiency proves to be a representative of the wire-wear. Moreover, the unique capability of the in situ bow measurement to provide a distribution of the measurements on the wire web during the cut allows studying the wire web behavior and the wire cutting efficiency distribution for different cutting conditions. Thanks to the innovative design of the instrumentation coupled with a data analysis based on a deep understanding of the involved physical phenomena, the in situ bow measurement is demonstrated to be a powerful tool to optimize the cutting process in terms of wafer quality and cost efficiency. Moreover, it can provide real-time information opening the door for tuning the parameters during the cutting process.
ABSTRACT
INTRODUCTION: We performed a non-inferiority study comparing magnetic resonance angiography (MRA) techniques including contrast-enhanced (CE) and time-of-flight (TOF) with brain digital subtraction arteriography (DSA) in localizing occlusion sites in acute ischemic stroke (AIS) with a prespecified inferiority margin taking into account thrombus migration. MATERIALS AND METHODS: HIBISCUS-STROKE (CoHort of Patients to Identify Biological and Imaging markerS of CardiovascUlar Outcomes in Stroke) includes large-vessel-occlusion (LVO) AIS treated with mechanical thrombectomy (MT) following brain magnetic resonance imaging (MRI) including both CE-MRA and TOF-MRA. Locations of arterial occlusions were assessed independently for both MRA techniques and compared to brain DSA findings. Number of patients needed was 48 patients to exclude a difference of more than 20%. Discrepancy factors were assessed using univariate general linear models analysis. RESULTS: The study included 151 patients with a mean age of 67.6±15.9years. In all included patients, TOF-MRA and CE-MRA detected arterial occlusions, which were confirmed by brain DSA. For CE-MRA, 38 (25.17%) patients had discordant findings compared with brain DSA and 50 patients (33.11%) with TOF-MRA. The discordance factors were identical for both MRA techniques namely, tandem occlusions (OR=1.29, P=0.004 for CE-MRA and OR=1.61, P<0.001 for TOF-MRA), proximal internal carotid artery occlusions (OR=1.30, P=0.002 for CE-MRA and OR=1.47, P<0.001 for TOF-MRA) and time from MRI to MT (OR=1.01, P=0.01 for CE-MRA and OR=1.01, P=0.02 for TOF-MRA). CONCLUSION: Both MRA techniques are inferior to brain DSA in localizing arterial occlusions in LVO-AIS patients despite addressing the migratory nature of the thrombus.
Subject(s)
Arterial Occlusive Diseases , Ischemic Stroke , Stroke , Aged , Aged, 80 and over , Angiography, Digital Subtraction/methods , Brain , Contrast Media , Humans , Magnetic Resonance Angiography/methods , Middle Aged , Sensitivity and Specificity , Stroke/diagnostic imaging , Stroke/surgery , ThrombectomyABSTRACT
The conventional sea level budget (SLB) equates changes in sea surface height with the sum of ocean mass and steric change, where solid-Earth movements are included as corrections but limited to the impact of glacial isostatic adjustment. However, changes in ocean mass load also deform the ocean bottom elastically. Until the early 2000s, ocean mass change was relatively small, translating into negligible elastic ocean bottom deformation (OBD), hence neglected in the SLB equation. However, recently ocean mass has increased rapidly; hence, OBD is no longer negligible and likely of similar magnitude to the deep steric sea level contribution. Here, we use a mass-volume framework, which allows the ocean bottom to respond to mass load, to derive a SLB equation that includes OBD. We discuss the theoretical appearance of OBD in the SLB equation and its implications for the global SLB.
ABSTRACT
INTRODUCTION: Orolingual angioedema (OA) is a known adverse effect of intravenous (i.v.) alteplase. We analyzed all patients treated with i.v. alteplase for stroke at our hospital since approval of i.v. thrombolysis in Italy in 2004 to assess the incidence of this complication. PATIENTS AND RESULTS: Four hundred thirty-three patients received alteplase for stroke from April 2004 to May 2017. Two women developed OA (0.4%; 95% confidence interval 0.1 to 1.6%). Angioedema was mild in one case and severe in the other, with massive swelling of the lips, tongue, and oropharyngeal mucosa, and oropharyngeal bleeding, requiring intubation. Neither patient used ACE-inhibitors. DISCUSSION: The incidence of orolingual angioedema was very low in our series. Although OA is usually mild, anaphylactoid reactions may rarely occur, because of the variable degree of activation of the complement system and kinin cascade caused by alteplase. In such instances, admission to neurointensive care may be required. Specific bradykinin antagonists or drugs that target the kallikrein-kinin system are beginning to be used in the more severe cases. Thus, doctors and nurses caring for acute stroke patients need to be able to recognize and treat this complication.
Subject(s)
Angioedema/chemically induced , Angioedema/epidemiology , Fibrinolytic Agents/administration & dosage , Stroke/therapy , Tissue Plasminogen Activator/administration & dosage , Administration, Intravenous , Aged , Aged, 80 and over , Female , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Severity of Illness Index , Stroke/epidemiologyABSTRACT
INTRODUCTION: Vertebral hemangiomas (VH) represent the most common primary bone tumor of the spine and are rarely symptomatic. Currently, there is no consensus for treatment and many therapeutic options are available, alone or in combination including cementoplasty, sclerotherapy, surgery, embolization and/or radiotherapy. OBJECTIVE: To evaluate the clinical and radiological outcome of a multimodal management for symptomatic VH. METHODS: A consecutive prospective and retrospective multicenter study was conducted to review cases of symptomatic VHs between 2005 and 2015. Clinical and radiological aspects, treatment modalities and complications were evaluated preoperatively; postoperatively and at last follow-up. We also reviewed the literature of studies concerning case series of VH, published after 1990 and involving more than 10 patients. RESULTS: Twenty-seven VHs were included in our series (mean age at diagnosis: 47.9 years), out of which 26 were symptomatic. Ten presented with neurologic deficit (37%). An epidural extension was noted in 13 patients (48%). Eleven patients (41%) underwent multimodal treatments. In the multimodal group, eradication was observed in 6 patients (54%), stable residue in 5 cases (46%) with no recurrence versus 3 eradication (23%), 9 stable residue (69%) and no recurrence in the monomodal group, (P>0.05). The literature comprised 14 studies including 458 patients. Only 4 studies were focused on multimodal treatments. CONCLUSION: Based on this study, the multimodal management of symptomatic VHs appeared safe and effective. Finally, we propose an algorithm for symptomatic VHS management based on the severity of epidural extension and fracture risk.
Subject(s)
Hemangioma/therapy , Spinal Neoplasms/therapy , Algorithms , Combined Modality Therapy , Humans , Middle Aged , Prospective Studies , Retrospective StudiesABSTRACT
BACKGROUND: The European Veterinary Renal Pathology Service (EVRPS) is the first Web-based registry for canine renal biopsy specimens in Europe. HYPOTHESIS/OBJECTIVES: The aim was to verify whether differences exist between the clinical and laboratory presentation of dogs with nephropathy according to renal pathological findings, as defined by light and electron microscopy of renal biopsy specimens submitted to EVRPS. ANIMALS: Renal biopsy specimens of dogs were collected from the archive of the service (n = 254). Cases were included if both light and electron microscopy were available (n = 162). METHODS: Renal biopsy specimens were classified based on the morphological diagnoses. Thereafter, they were grouped into 3 disease categories, including immune-complex-mediated glomerulonephritis (ICGN), non-immune-complex-mediated GN (non-ICGN), and renal lesions not otherwise specified (RL-NOS). Differences among morphological diagnoses and among disease categories were investigated for clinical and laboratory variables. RESULTS: Serum albumin concentration was lower in dogs with ICGN than in those with non-ICGN (P = 0.006) or RL-NOS (P = 0.000), and the urine protein-to-creatinine ratio (UPC) was significantly higher in ICGN than in the other 2 disease categories. Regarding morphological diagnoses, albumin was significantly lower in amyloidosis (AMY) and membranous (MGN), membranoproliferative (MPGN) or mixed glomerulonephritis (MixGN) than in minimal change disease, primary (FSGS I) or secondary (FSGS II) focal and segmental glomerulosclerosis and juvenile nephropathies (JN). The UPC was higher in MPGN than in FSGS I and FSGS II. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with ICGN, in particular MPGN, had higher protein loss than those with non-ICGN or RL-NOS, leading to more severe hypoalbuminemia. Clinical and laboratory differentiation among dogs with the different morphological diagnoses and among dogs with different disease categories was difficult due to overlapping results.
Subject(s)
Dog Diseases/pathology , Kidney Diseases/veterinary , Kidney/pathology , Animals , Biopsy/veterinary , Dogs , Europe , Female , Glomerulonephritis/pathology , Glomerulonephritis/veterinary , Kidney Diseases/pathology , Male , Microscopy/veterinary , Microscopy, Electron/veterinary , Registries , Surveys and QuestionnairesABSTRACT
The Pediatric Anesthesia Neuro Development Assessment (PANDA) team at the Anesthesiology Department at Columbia University Medical Center held its fifth biennial symposium to discuss issues regarding potential neurotoxicity of anesthetic agents in pediatric patients. Overall optimal surgical timing as well as a "critical window" for surgery on a specialty specific basis are areas of focus for the American Academy of Pediatrics Surgical Advisory Panel. An ad hoc panel of pediatric surgical experts representing general surgery, urology, neurosurgery, and ophthalmology was assembled for this meeting and provided a dialogue focused on the benefits of early intervention versus potential anesthetic risk, addressing parental concerns, and the need for continued interdisciplinary collaboration in this area.
Subject(s)
Anesthetics/adverse effects , Neurotoxicity Syndromes/prevention & control , Age Factors , Animals , Child , HumansABSTRACT
Neurotoxicity related to early exposure to various insults, both anesthesia-related and nonanesthesia-related, is a topic of ongoing and increasing interest. To better understand the process by which this might occur, the fifth PANDA Symposium convened a session in which 4 notable neuroscientists discussed current concepts and research in neurodevelopment, highlighting periods of particular susceptibility and ways in which neural connectivity and systemic functioning may be affected.
ABSTRACT
A new methodology is proposed to estimate changes in the Earth's dynamic oblateness ([Formula: see text] or equivalently, [Formula: see text]) on a monthly basis. The algorithm uses monthly Gravity Recovery and Climate Experiment (GRACE) gravity solutions, an ocean bottom pressure model and a glacial isostatic adjustment (GIA) model. The resulting time series agree remarkably well with a solution based on satellite laser ranging (SLR) data. Seasonal variations of the obtained time series show little sensitivity to the choice of GRACE solutions. Reducing signal leakage in coastal areas when dealing with GRACE data and accounting for self-attraction and loading effects when dealing with water redistribution in the ocean is crucial in achieving close agreement with the SLR-based solution in terms of de-trended solutions. The obtained trend estimates, on the other hand, may be less accurate due to their dependence on the GIA models, which still carry large uncertainties.
Subject(s)
Infarction, Middle Cerebral Artery/drug therapy , Infarction, Middle Cerebral Artery/surgery , Stroke/drug therapy , Stroke/surgery , Thrombectomy , Thrombolytic Therapy , Combined Modality Therapy , Humans , Infarction, Middle Cerebral Artery/complications , Randomized Controlled Trials as Topic , Stroke/complications , Treatment OutcomeABSTRACT
The PulseRider is a novel endovascular device specifically designed to treat bifurcation intracranial aneurysms with wide necks. In an international series, we report the results of PulseRider stent-assisted coiling of 15 patients (9 women and 6 men; mean age, 62.6 years) with 15 unruptured wide-neck (median dome size, 8 mm; median neck size, 5 mm) bifurcation aneurysms. Failure of PulseRider treatment occurred in 1 case, and 1 intraprocedural thromboembolic complication was observed. There was no mortality or neurologic permanent morbidity at discharge and at 1 month. Immediate angiographic outcome showed 12 complete occlusions and 2 neck remnants. Follow-up at 6 months was available for 3 aneurysms and demonstrated 2 complete aneurysm occlusions and 1 growing neck remnant. In this small series of selected patients, PulseRider stent-assisted coiling of wide-neck bifurcation aneurysms was feasible with low procedural complication rates. Angiographic follow-up will be required to evaluate the efficacy of the PulseRider device.
Subject(s)
Alloys , Embolization, Therapeutic/instrumentation , Intracranial Aneurysm/therapy , Stents , Adult , Aged , Cerebral Angiography/instrumentation , Equipment Design , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnostic imaging , Male , Middle Aged , Retrospective Studies , Treatment Failure , Treatment OutcomeABSTRACT
The functional benefit of stent retriever thrombectomy in acute ischemic stroke has been clearly demonstrated in recent positive MR CLEAN, ESCAPE, EXTEND-IA, SWIFT PRIME, REVASCAT and THRACE trials. Thrombectomy, in association with intravenous thrombolysis, should now be offered to patients with documented occlusion of the distal internal carotid or proximal middle cerebral arteries, with a relatively normal unenhanced computed tomography (CT), and within 6hours after the onset of symptoms. Thrombectomy results in a mean absolute decrease in handicap of 22% (14 to 31%). Of the 3 up to 8 patients treated, 1 is independent at 3 months according to the initial selection. In case of a contraindication to thrombolysis, early primary thrombectomy should be considered. In acute basilar artery occlusion, thrombectomy should be performed alone or combined with thrombolysis. In an effort to increase the number of patients treated, a very rapid transfer to interventional neuroradiology centers is mandatory. In the future, thrombectomy should be evaluated in patients with distal arterial occlusion, or beyond 6hours after the onset of symptoms, or when the time of symptoms onset is unknown.
Subject(s)
Brain Ischemia/surgery , Stents , Stroke/surgery , Thrombectomy/instrumentation , Thrombectomy/methods , Brain Ischemia/complications , Humans , Stroke/etiology , Treatment OutcomeABSTRACT
BACKGROUND AND PURPOSE: Despite the improvement in technology, endovascular treatment of bifurcation intracranial wide-neck aneurysms remains challenging, mainly due to the difficulty of maintaining coils within the aneurysm sac without compromising the patency of bifurcation arteries. The Woven EndoBridge (WEB) device is a recent intrasaccular braided device specifically dedicated to treating such aneurysms with a wide neck by disrupting the flow in the aneurysmal neck and promoting progressive aneurysmal thrombosis. MATERIALS AND METHODS: Using several health data bases, we conducted a systematic review of all published studies of WEB endovascular treatment in intracranial aneurysms from 2010 onward to evaluate its efficacy and safety profile. RESULTS: The literature search identified 6 relevant studies (7 articles) including wide-neck bifurcation aneurysms in ≥80% of cases. Clinical data supporting the efficacy and safety of the WEB are limited to noncomparative cohort studies with large heterogeneity from a methodologic standpoint. The WEB deployment was feasible with a success rate of 93%-100%. Permanent morbidity (mRS of >1 at last follow-up) and mortality were measured at 2.2%-6.7% and 0%-17%, respectively. The adequate occlusion rate (total occlusion or neck remnant) varied between 65% and 85.4% at midterm follow-up (range, 3.3-27.4 months). CONCLUSIONS: Endovascular treatment of bifurcation wide-neck aneurysms with the WEB device is feasible and allows an acceptably adequate aneurysm occlusion rate; however, the rate of neck remnants is not negligible. The WEB device needs further clinical and anatomic evaluation with long-term prospective studies, especially of the risk of WEB compression. Prospective controlled studies should be encouraged.
Subject(s)
Embolization, Therapeutic/instrumentation , Endovascular Procedures/instrumentation , Intracranial Aneurysm/therapy , Blood Vessel Prosthesis/adverse effects , Embolization, Therapeutic/adverse effects , Endovascular Procedures/adverse effects , Humans , Treatment OutcomeABSTRACT
BACKGROUND AND PURPOSE: Endovascular coiling of wide-neck intracranial aneurysms is associated with low rates of initial angiographic occlusion and high rates of recurrence. The WEB intrasaccular device has been developed specifically for this indication. To date, there has been no report of the long-term follow-up of a series of patients with aneurysms treated with this type of device, to our knowledge. Our aim was to evaluate a 1-year follow-up of angiographic results in a prospective single-center series of patients treated with the WEB-Single-Layer (SL) device. MATERIALS AND METHODS: All patients treated with the WEB-SL device in our center between August 2013 and May 2014 were prospectively included. One-year angiographic outcomes were assessed. Results at follow-up were graded as complete occlusion, neck remnant, or residual aneurysm. RESULTS: Eight patients with 8 unruptured wide-neck aneurysms were enrolled in this study. Average dome width was 7.5 mm (range, 5.4-10.7 mm), and average neck size was 4.9 mm (range, 2.6-6.5 mm). One-year angiographic follow-up obtained in all aneurysms included 1 complete aneurysm occlusion (12.5%), 6 neck remnants (75%), and 1 aneurysm remnant (12.5%). Of 8 aneurysms, worsening of aneurysm occlusion was observed in 2 (25%) by compression of the WEB device. There was no angiographic recurrence of initially totally occluded aneurysms. No bleeding was observed during the follow-up period. CONCLUSIONS: Endovascular therapy of intracranial aneurysms with the WEB-SL device allows treatment of wide-neck aneurysms with a high rate of neck remnant at 1 year, at least partially explained by WEB compression. Initial size selection and technologic improvements could be an option for optimization of aneurysm occlusion in WEB-SL treatment.
Subject(s)
Embolization, Therapeutic/instrumentation , Endovascular Procedures/instrumentation , Intracranial Aneurysm/therapy , Adult , Cerebral Angiography , Embolization, Therapeutic/adverse effects , Embolization, Therapeutic/methods , Endovascular Procedures/adverse effects , Endovascular Procedures/methods , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnostic imaging , Male , Middle Aged , Prospective Studies , Recurrence , Treatment OutcomeSubject(s)
Infarction, Middle Cerebral Artery/surgery , Thrombectomy/methods , Acute Disease , Aged , Angioplasty , Carotid Stenosis/complications , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/therapy , Combined Modality Therapy , Contraindications , Endarterectomy , Humans , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/diagnostic imaging , Infarction, Middle Cerebral Artery/drug therapy , Male , Paresis/etiology , Recurrence , Reoperation , Thrombolytic Therapy , Tomography, X-Ray ComputedABSTRACT
BACKGROUND AND PURPOSE: Endovascular treatment of wide-neck anterior communicating artery aneurysms can often be challenging. The Woven EndoBridge (WEB) device is a recently developed intrasaccular flow disrupter dedicated to endovascular treatment of intracranial aneurysms. The aim of this study was to investigate the feasibility, safety, and efficacy of the WEB Dual-Layer and WEB Single-Layer devices for the treatment of wide-neck anterior communicating artery aneurysms. MATERIALS AND METHODS: Patients with anterior communicating artery aneurysms treated with the WEB device between June 2013 and March 2014 in 5 French centers were analyzed. Procedural success, technical complications, clinical outcome at 1 month, and immediate and 3- to 6-month angiographic follow-up results were analyzed. RESULTS: Ten patients with unruptured anterior communicating artery aneurysms with a mean neck diameter of 5.4 mm were treated with the WEB. Treatment failed in 3 of the 10 aneurysms without further clinical complications. One patient developed a procedural thromboembolic event, and the other 6 had normal neurologic examination findings at 1-month follow-up. Immediate anatomic outcome evaluation showed adequate occlusion (total occlusion or neck remnant) in 6 of 7 patients. Angiographic control was obtained in all patients, including 6 adequate aneurysm occlusions (3 complete occlusions and 3 neck remnants) at short-term follow-up. CONCLUSIONS: In our small series, treatment of wide-neck anterior communicating artery aneurysms with the WEB device was feasible and safe. However, patient selection based on the aneurysm and initial angiographic findings in the parent artery is important due to the limitations of the WEB device navigation.