ABSTRACT
Thyroid radiofrequency ablation and microwave ablation are widely adopted minimally invasive treatments for diverse thyroid conditions worldwide. Fundamental skills such as the trans-isthmic approach and the moving shot technique are crucial for performing thyroid ablation, and advanced techniques, including hydrodissection and vascular ablation, improve safety and efficacy and reduce complications. Given the learning curve associated with ultrasound-guided therapeutic procedures, operators need training and experience. While training models exist, limited attention has been given to ultrasound maneuvers in ablation needle manipulation. This article introduces two essential maneuvers, the zigzag moving technique and the alienate maneuver, while also reviewing the latest ultrasound techniques in thyroid ablation, contributing valuable insights into this evolving field.
ABSTRACT
<p><b>OBJECTIVE</b>To assess the value of magnetic resonance (MR) myocardial perfusion imaging (MRMPI) in evaluating the myocardial viability in patients with myocardial infarction.</p><p><b>METHODS</b>MRMPI was performed in 51 patients with myocardial infarction using a 1.5 T MR scanner. All the patients were examined using IR-turbo FLASH sequence during the first-pass and delayed phase 5-30 min after injection of 0.1 mmol/kg Gd-DTPA at the rate of 4 ml/s. The short axis images were acquired during the first-pass, and both the short axis and long axis images were obtained during the delayed phase. The left ventricular wall on the short-axis slice was divided into 8 segments. A correlative study of the results of the rest and stress (99m)Tc single photon emission computed tomography (SPECT) was carried out in 21 patients.</p><p><b>RESULTS</b>In the 51 patients with myocardial infarction, 42(82.3%) showed hypoperfusion during the first-pass imaging and 50(98%) had delayed hyperenhancement. In the 21 patients receiving SPECT, 48 nonviable segments was detected among the 168 segments scanned by (99m)TcSPECT, and MRMPI showed delayed hyperenhancement in all the infracted areas. Of the 120 viable segments detected by rest and stress (99m)Tc SPECT, 97 segments (80.8%) were found to be free of delayed hyperenhancement by MRMPI. With the rest and stress (99m)Tc SPECT as the reference, the sensitivity and the specificity of MRMPI were 100.0% and 80.8%, respectively.</p><p><b>CONCLUSION</b>MRMPI allows effective identification of the myocardial viability and nonviability as well as the severity and extent of the myocardial infraction.</p>