Model-based vs hybrid iterative reconstruction technique in ultralow-dose submillisievert CT colonography.

OBJECTIVE: To compare image quality of different reconstruction techniques in submillisievert ultralow-dose CT colonography (CTC) and to correlate colonic findings with subsequent optical colonoscopy. METHODS: 58 patients underwent ultralow-dose CTC. The images were reconstructed with filtered back projection (FBP), hybrid iterative reconstruction (HIR) or model-based iterative reconstruction (MBIR) techniques. In each segment, endoluminal noise (expressed as standard deviation of endoluminal density) was measured and image quality was rated on a five-point Likert scale by two independent readers. Colonic lesions were evaluated in consensus and correlated with subsequent optical colonoscopy where possible. RESULTS: The estimated radiation dose was 0.41 ± 0.05 mSv for the supine and 0.42 ± 0.04 mSv for the prone acquisitions. In the endoluminal view, the image quality was rated better in HIR, whereas better scores were obtained in MBIR in the cross-sectional view, where the endoluminal noise was the lowest (p < 0.0001). Five (26%) polyps were not identified using both computer-aided detection and endoluminal inspection in FBP images vs only one (5%) in MBIR and none in HIR images. CONCLUSION: This study showed that in submillisievert ultralow-dose CTC, the image quality for the endoluminal view is better when HIR is used, whereas MBIR yields superior images for the cross-sectional view. The inferior quality of images reconstructed with FBP may result in decreased detection of colonic lesions. ADVANCES IN KNOWLEDGE: Radiation dose from CTC can be safely reduced <1 mSv for both positions when iterative reconstruction is used. MBIR provides better image quality in the cross-sectional view and HIR in the endoluminal view.

Exogenous surfactant as a component of complex non-ECMO therapy of ARDS caused by influenza A virus (2009 H1N1).

During the pandemy caused by novel influenza A virus (subgroup H1N1), a significant number of patients became critically ill from respiratory failure. In the most severe cases of primary pneumonia, patients develop refractory hypoxemic acute respiratory distress syndrome (ARDS) with typical computed tomographic findings of multi-lobar alveolar opacities and extremely reduced pulmonary airspace. To reduce the risk of injurious ventilation and promote survival, some authors recommend the use of extracorporeal membrane oxygenation (ECMO). Unfortunately, ECMO is expensive, associated with serious complications, and available at very few centers. Other therapeutic options are clearly needed. Here we report three patients with severe influenza pneumonia who recovered following treatment with porcine surfactant (Tab. 1, Fig. 3, Ref. 6). Full Text in free PDF www.bmj.sk.

[Ventilator-associated pneumonia]. / Ventilátorová pneumonie.

Ventilator-associated pneumonia (VAP) is defined as pneumonia occurring in a patient after intubation with an endotracheal tube or tracheostomy tube lasting for 48 hours or more. It is also one of the most common and fatal infections of patients in ICUs. The diagnostic process in VAP is still underestimated and precise criteria for diagnosis are inconsistent. Delayed diagnosis and subsequent delay in starting appropriate therapy are associated with worse outcomes in patients with VAP. Appropriate dose, adequate route of administration and reasonable length of antibiotic therapy together with de-escalation are the fundamental principles of therapy. Supportive care is also an integral part of the treatment. Implementing preventive procedures according to the local ICU standards is needed for reducing the incidence of VAP effectively.

Thrombolysis and cardiac arrest.

Cardiac arrest (CA) is a serious clinical condition that might be responsible in many cases for death, in other at least for development of irreversible multiple organ dysfunctions. During and after the CA a significant coagulopathy develops causing a decrease in proper tissue perfusion even if an early return of spontaneous circulation (ROSC) is achieved (no-reflow phenomenon). Administration of thrombolytics can solve the problem by destructing the blood clot in both macrocirculation and microcirculation. Results of some clinical trials proving an effectiveness of thrombolysis were published in the literature. Generally, it was done by describing its positive influence on some important clinical outcome measures (24hour survival, number of hospital admissions, better neurological status etc.) without significant increase in the number of bleeding complications. However, recent pivotal evidence based medicine (EBM) trial represented by TROICA study did not confirm the expected positive results. Because of that and also for other reasons (cost, fear of adverse effects, little practice etc.) thrombolysis, although theoretically promising therapeutical intervention, is not overly recommended and used in routine clinical practice in both out-of-hospital and in-hospital settings (Fig. 2, Tab. 4, Ref. 24). Full Text in free PDF www.bmj.sk.

[Contribution and selected risks of blood transfusion]. / Prínos a vybraná rizika krevních prevodu.

AIM: Overview of recent knowledge about risks and benefits of blood transfusion. TYPE OF STUDY: Review article. SETTING: Department of Anaesthesiology and Intensive Care, University Hospital, Ostrava. METHODS: Summary of previously published data. CONCLUSION: Transfusion of blood and blood products remains controversial in clinical practice. Neither indication and timing nor benefit of this procedure is clearly determined. Previously often reported complications as blood-group incompatibility and infection are less frequent now, and new transfusion's side effects as TRIM (transfusion-related immunomodulation) and TRALI (transfusion-related lung injury) are reported with growing evidence. This risk (often underestimated in the past) is discussed in the article, and compared with blood transfusion benefits. Either restrictive or more open approach to blood transfusion are supported as well as criticised by different groups of clinicians and "good clinical practice" definition remains open for the future.