Adaptive singular value decomposition filtering of high-intensity focused ultrasound interference enables real-time ultrasound-guided therapy

High-intensity focused ultrasound (HIFU) is an emerging therapeutic tool for the effective thermal ablation of pathological tissue. For accurate localization of the target and safe control of the HIFU dosage, real-time imaging guidance during the HIFU exposure is desired. Ultrasound imaging has the capability to guide clinicians toward a lesion in real time, but is not an ideal option, as HIFU application causes strong interference, thereby substantially distorting the images used for guidance. Thus, this study introduces singular value decomposition–based filtering capable of restoring ultrasound harmonic images from HIFU interference without undesirable spectral distortion. The results were experimentally validated with a custom-made phantom, indicating that this approach effectively eliminates HIFU-induced artifacts, which is essential for real-time monitoring of the therapeutic process.

Beneficial aspect of dexmedetomidine as a postoperative sedative for cardiac surgery

BACKGROUND: The aim of this study was to compare the clinical outcomes of the sedative, analgesic, and hemodynamic effects of dexmedetomidine and midazolam for sedation after coronary artery bypass grafting (CABG). METHODS: The adult patients undergoing elective CABG surgery under general anesthesia were randomly assigned to the dexmedetomidine (DEX) and midazolam (MDZ) groups. From the time of the sternal closure, dexmedetomidine (0.5–0.7 μg/kg/h) was continuously administered (DEX group), and midazolam (0.03–0.1 mg/kg) was administered by bolus (MDZ group). To maintain the target sedation level (Richmond Agitation-Sedation Scale [RASS] range, −2 to −1) until extubation in the intensive care unit (ICU), continuous doses of dexmedetomidine were regulated and midazolam was administered intermittently. Sedation (RASS) and pain scores (visual analogue scale) and hemodynamic changes were recorded every two hours, until the end of the mechanical ventilation assistance after entering the ICU. RESULTS: The mean of the fraction within the target sedation level in each patient's total sedation time was 41.0% in the DEX group and 20.7% in the MDZ group (P = 0.026). In the DEX group, the RASS (P < 0.001) and cardiac index were lower (P = 0.047) than those in the MDZ group, but the other hemodynamic parameters and pain scores were not different. CONCLUSIONS: This study showed that post-operative infusion of dexmedetomidine maintained a stable sedation without side effects in patients who underwent CABG surgery.

Stented Aortic Graft Insertion in an Infrarenal Abdominal Aortic Aneurysm as Performed by Cardiovascular Surgeons: Report of 3 cases / 대한흉부외과학회지

Abdominal aortic aneurysm has traditionally been treated by open repair. Aortic endovascular stent grafting has recently been introduced as a new modality. We report here on three cases of endovascular stent grafting that were performed by cardiovascular surgeons for the treatment of abdominal aortic aneurysm in the high risk patients with multiple comorbidities such as old age, hypertension, renal failure, cerebrovascular accident and immobility.