Magnetic resonance elastography with guided pressure waves

Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.     

Cardiac Surgery in Patients With Liver Cirrhosis (CASTER) Study: Early and Long-Term Outcomes

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Neonatal Cardiac Arrest From Left Ventricular Cardiac Hemangioma: A Surprising Presentation

Cardiac hemangioma is rare, even more when leading to a cardiovascular collapse in a seemingly healthy newborn. A 6-day-old neonate had a tamponade caused by a basolateral hemangioma of the left ventricle. Partial surgical resection was performed. A congenital lobular capillary hemangioma was diagnosed upon histologic examination. The patient recovered completely and shows normal development at the 12-month follow-up.     

A randomised controlled trial of intravenous dexmedetomidine added to dexamethasone for arthroscopic rotator cuff repair and duration of interscalene block

Prolongation of peripheral nerve blockade by intravenous dexamethasone may be extended by intravenous dexmedetomidine. We randomly allocated 122 participants who had intravenous dexamethasone 0.15 mg.kg⁻¹ before interscalene brachial plexus block for day-case arthroscopic rotator cuff repair to intravenous saline (62 participants) or intravenous dexmedetomidine 1 μg.kg⁻¹ (60 participants). The primary outcome was time from block to first oral morphine intake during the first 48 postoperative hours. Fifty-nine participants reported taking oral morphine, 25/62 after placebo and 34/60 after dexmedetomidine, p = 0.10. The time to morphine intake was shorter after dexmedetomidine, hazard ratio (95%CI) 1.68 (1.00–2.82), p = 0.049. Median (IQR [range]) morphine doses were 0 (0–12.5 [0–50]) mg after control vs. 10 (0–30 [0–50]) after dexmedetomidine, a difference (95%CI) of 7 (0–10) mg, p = 0.056. There was no effect of dexmedetomidine on pain at rest or on movement. Intra-operative hypotension was recorded for 27/62 and 50/60 participants after placebo vs. dexmedetomidine, respectively, p < 0.001. Other outcomes were similar, including durations of sensory and motor block. In conclusion, dexmedetomidine shortened the time to oral morphine consumption after interscalene block combined with dexamethasone and caused intra-operative hypotension.