LISA:a lightweight stratospheric air sampler

We developed a new lightweight stratospheric air sampler (LISA). The LISA sampler is designed to collect four bag samples in the stratosphere during a balloon flight for CO2, CH4 and CO mole fraction measurements. It consists of four multi-layer foil (MLF) sampling bags, a custom-made manifold, and a diaphragm pump, with a total weight of ∼2.5 kg. A series of laboratory storage tests were performed to assess the stability of CO2, CH4 and CO mole fractions in both MLF and Tedlar bags. The MLF bag was chosen due to its better overall performance than the Tedlar bag for the three species CO2, CH4 and CO. Furthermore, we evaluated the performance of the pump under low pressure conditions to optimize a trade-off between the vertical resolution and the sample size. The LISA sampler was flown on the same balloon flight with an AirCore in Sodankylä, Finland (67.368∘ N, 26.633∘ E, 179 m a.s.l.), on 26 April and 4–7 September 2017. A total of 15 stratospheric air samples were obtained during the ascent of four flights. The sample size ranges between 800 and 180 mL for the altitude between 12 and 25 km, with the corresponding vertical resolution ranging from 0.5 to 1.5 km. The collected air samples were analysed for CO2, CH4 and CO mole fractions, and evaluated against AirCore retrieved profiles, showing mean differences of 0.84 ppm for CO2, 1.8 ppb for CH4 and 6.3 ppb for CO, respectively. High-accuracy stratospheric measurements of greenhouse gas mole fractions are useful to validate remote sensing measurements from ground and from space, which has been performed primarily by comparison with collocated aircraft measurements (0.15–13 km), and more recently with AirCore observations (0–30 km). While AirCore is capable of achieving high-accuracy greenhouse gas mole fraction measurements, it is challenging to obtain accurate altitude registration for AirCore measurements. The LISA sampler provides a viable low-cost tool for retrieving stratospheric air samples for greenhouse gas measurements that is complementary to AirCore. Furthermore, the LISA sampler is advantageous in both the vertical resolution and sample size for performing routine stratospheric measurements of the isotopic composition of trace gases

No evidence for the effectiveness of bracing in patients with thoracolumbar fractures

Background and purpose The use of braces is widespread in patients with thoracolumbar fractures. The effectiveness of bracing, however, is controversial. We sought evidence for the effect of bracing in patients with traumatic thoracolumbar fractures based on outcome and length of hospital stay (LOS). Furthermore, we evaluated the incidence of complications of bracing. Methods An electronic search strategy with extensive MeSH headings was used in various databases to identify studies that compared bracing and non-bracing therapies. Two reviewers independently selected systematic reviews, randomized controlled trials (RCTs), controlled clinical trials, and observational studies, and both assessed the methodological quality and extracted the data. Results No systematic reviews or RCTs were found. 7 retrospective studies were included. None of these studies showed an effect of bracing. Because of poor methodological quality, no best-evidence synthesis could be performed. One observational study was selected in which a complication of bracing was reported. Interpretation In the present literature, there is no evidence for the effectiveness of bracing in patients with traumatic thoracolumbar fractures. The lack of high-quality studies prevents relevant conclusions from being draw

Endovascular graft for late iatrogenic vascular complication after anterior spinal instrumentation: a case report

STUDY DESIGN: Case report. OBJECTIVE: To describe an endovascular treatment option for (late) vascular complications after anterior spinal instrumentation. SUMMARY OF BACKGROUND DATA: Severe progressive scoliosis is a well-known feature in Marfan's disease. Although overall complication rate after surgical correction of the spinal deformity is rather high, late iatrogenic complications are less frequently identified. METHODS: A 40-year-old woman with Marfan's disease reported to our outpatient clinic with dyspnoe d'effort, 20 years after anterior spinal instrumentation of a thoracolumbar scoliosis. Routine screening identified a saccular aneurysm of the descending thoracic aorta. A contrast-enhanced CT scan revealed that the most proximal screw of the construct had perforated the vessel wall and caused a false aneurysm. An endovascular approach to the problem was chosen; by a transfemoral approach, an AneuRx endovascular graft was successfully implanted. RESULTS: The patient had an uneventful postoperative course and was discharged within 5 days. At 5-year follow-up, the patient still has no clinical complaints, nor radiographic leakage nor recurrence of the false aneurysm at contrast-enhanced CT screening. CONCLUSION: Use of an endovascular graft is an adequate alternative for treatment of late vascular complications after anterior spinal instrumentatio

Suspected atlantoaxial rotatory fixation-subluxation: the value of multidetector computed tomography scanning under general anesthesia

STUDY DESIGN: Clinical case reports and radiologic study. OBJECTIVES: To emphasize the value of computed tomography (CT) scan under general anesthesia in order to prevent misdiagnosing atlantoaxial rotatory fixation-subluxation in children with acute torticollis. SUMMARY OF BACKGROUND DATA: A "cock-robin" posture clinically characterizes painful rotatory fixation of the atlantoaxial joint in children. Classically, the observation of persistent displacement of the dens between the lateral mass of the atlas and asymmetry of the atlantoaxial joint on radiography confirmed the diagnosis. More recently, (dynamic) CT scanning or magnetic resonance imaging is used to confirm the diagnosis. However, when a CT scan is performed with the head of the patient in the "cock-robin" position, there is a serious chance of misinterpretation due to the abnormal anatomic position of the atlantoaxial joint. METHODS: Four consecutive cases of children presenting with an acute torticollis were analyzed. All were neurologically intact. A conventional single-slice CT scan made with the head rotated in the "cock-robin" position confined rotatory dislocation of the atlantoaxial joint. Subsequently, the patients were referred to our hospital for further treatment. To confirm the diagnosis before potential treatment, a multidetector CT scan under general anesthesia was performed in all 4. RESULTS: The multidetector CT scans under general anesthesia did not show any abnormalities. All patients were treated conservatively and recovered completely within 4 weeks of being referred to our hospital. CONCLUSIONS: Multidetector CT scanning under general anesthesia is recommended in children when there is suspicion for a spontaneously developed atlantoaxial rotatory fixation-subluxatio

Perioperative systemic therapy and cytoreductive surgery with HIPEC versus upfront cytoreductive surgery with HIPEC alone for isolated resectable colorectal peritoneal metastases: Protocol of a multicentre, open-label, parralel-group, phase II-III, randomised, superiority study (CAIRO6)

Background: Upfront cytoreductive surgery with HIPEC (CRS-HIPEC) is the standard treatment for isolated resectable colorectal peritoneal metastases (PM) in the Netherlands. This study investigates whether addition of perioperative systemic therapy to CRS-HIPEC improves oncological outcomes. Methods: This open-label, parallel-group, phase II-III, randomised, superiority study is performed in nine Dutch tertiary referral centres. Eligible patients are adults who have a good performance status, histologically or cytologically proven resectable PM of a colorectal adenocarcinoma, no systemic colorectal metastases, no systemic therapy for colorectal cancer within six months prior to enrolment, and no previous CRS-HIPEC. Eligible patients are randomised (1:1) to perioperative systemic therapy and CRS-HIPEC (experimental arm) or upfront CRS-HIPEC alone (control arm) by using central randomisation software with minimisation stratified by a peritoneal cancer index of 0-10 or 11-20, metachronous or synchronous PM, previous systemic therapy for colorectal cancer, and HIPEC with oxaliplatin or mitomycin C. At the treating physician's discretion, perioperative systemic therapy consists of either four 3-weekly neoadjuvant and adjuvant cycles of capecitabine with oxaliplatin (CAPOX), six 2-weekly neoadjuvant and adjuvant cycles of 5-fluorouracil/leucovorin with oxaliplatin (FOLFOX), or six 2-weekly neoadjuvant cycles of 5-fluorouracil/leucovorin with irinotecan (FOLFIRI) followed by four 3-weekly (capecitabine) or six 2-weekly (5-fluorouracil/leucovorin) adjuvant cycles of fluoropyrimidine monotherapy. Bevacizumab is added to the first three (CAPOX) or four (FOLFOX/FOLFIRI) neoadjuvant cycles. The first 80 patients are enrolled in a phase II study to explore the feasibility of accrual and the feasibility, safety, and tolerance of perioperative systemic therapy. If predefined criteria of feasibility and safety are met, the study continues as a phase III study with 3-year overall survival as primary endpoint. A total of 358 patients is needed to detect the hypothesised 15% increase in 3-year overall survival (control arm 50%; experimental arm 65%). Secondary endpoints are surgical characteristics, major postoperative morbidity, progression-free survival, disease-free survival, health-related quality of life, costs, major systemic therapy related toxicity, and objective radiological and histopathological response rates. Discussion: This is the first randomised study that prospectively compares oncological outcomes of perioperative systemic therapy and CRS-HIPEC with upfront CRS-HIPEC alone for isolated resectable colorectal PM