Diagnostic Performance of Simulated Abbreviated MRI for Early-Stage Hepatocellular Carcinoma Screening: A Comparison to Conventional Dynamic Contrast-Enhanced MRI

Purpose@#To compare the per-patient diagnostic performance of simulated abbreviated MRI (AMRI) to that of conventional MRI (CMRI) with full-sequence dynamic gadoxetic acid (GA) enhancement for early-stage hepatocellular carcinoma (HCC) screening in high-risk patients. @*Materials and Methods@#A total of 201 consecutive patients at high-risk for HCC, who underwent 3T liver MRI, were included in this retrospective study. The AMRI protocol comprised T2-weighted imaging, hepatobiliary phase imaging after GA injection, and diffusion-weighted imaging. For each patient, two AMRI and CMRI image sets were independently reviewed by two radiologists.Inter-reader agreement was assessed using Cohen’s kappa value. A composite reference standard was used to determine the diagnostic performance of each image set for each reader. @*Results@#A total of 93 HCCs were detected in 79 patients. The inter-reader agreement was almost perfect for both image sets (κ = 0.839, 0.948). In AMRI, the per-patient sensitivity and negative predictive values (NPV) were 94.9% and 96.4%, respectively. In CMRI, the per-patient sensitivity and NPV were 96.2% and 97.5%, respectively. @*Conclusion@#AMRI, using only three sequences, had a comparable diagnostic performance to CMRI in screening early-stage HCC. AMRI could be an alternative HCC screening tool for highrisk HCC patients.

Diagnostic Performance of Simulated Abbreviated MRI for Early-Stage Hepatocellular Carcinoma Screening: A Comparison to Conventional Dynamic Contrast-Enhanced MRI

Purpose@#To compare the per-patient diagnostic performance of simulated abbreviated MRI (AMRI) to that of conventional MRI (CMRI) with full-sequence dynamic gadoxetic acid (GA) enhancement for early-stage hepatocellular carcinoma (HCC) screening in high-risk patients. @*Materials and Methods@#A total of 201 consecutive patients at high-risk for HCC, who underwent 3T liver MRI, were included in this retrospective study. The AMRI protocol comprised T2-weighted imaging, hepatobiliary phase imaging after GA injection, and diffusion-weighted imaging. For each patient, two AMRI and CMRI image sets were independently reviewed by two radiologists.Inter-reader agreement was assessed using Cohen’s kappa value. A composite reference standard was used to determine the diagnostic performance of each image set for each reader. @*Results@#A total of 93 HCCs were detected in 79 patients. The inter-reader agreement was almost perfect for both image sets (κ = 0.839, 0.948). In AMRI, the per-patient sensitivity and negative predictive values (NPV) were 94.9% and 96.4%, respectively. In CMRI, the per-patient sensitivity and NPV were 96.2% and 97.5%, respectively. @*Conclusion@#AMRI, using only three sequences, had a comparable diagnostic performance to CMRI in screening early-stage HCC. AMRI could be an alternative HCC screening tool for highrisk HCC patients.

Hepatic Arterial Phase on Gadoxetic Acid-Enhanced Liver MR Imaging: A Randomized Comparison of 0.5 mL/s and 1 mL/s Injection Rates

OBJECTIVE: To compare gadoxetic acid injection rates of 0.5 mL/s and 1 mL/s for hepatic arterial-phase magnetic resonance (MR) imaging. MATERIALS AND METHODS: In this prospective study, 101 consecutive patients with suspected focal liver lesions were included and randomly divided into two groups. Each group underwent dynamic liver MR imaging using a 3.0-T scanner after an intravenous injection of gadoxetic acid at rates of either 0.5 mL/s (n = 50) or 1 mL/s (n = 51). Arterial phase images were analyzed after blinding the injection rates. The signal-to-noise ratios (SNRs) of the liver, aorta, portal vein, hepatic vein, spleen, and pancreas were measured. The contrast-to-noise ratios (CNRs) of the hepatocellular carcinomas (HCC) were calculated. Finally, two experienced radiologists were independently asked to identify, if any, HCCs in the liver on the images and score the image quality in terms of the presence of artifacts and the proper enhancement of the liver, aorta, portal vein, hepatic vein, hepatic artery, spleen, pancreas, and kidney. RESULTS: The SNRs were not significantly different between the groups (p = 0.233-0.965). The CNRs of the HCCs were not significantly different (p = 0.597). The sensitivity for HCC detection and the image quality scores were not significantly different between the two injection rates (p = 0.082-1.000). CONCLUSION: Image quality and sensitivity for hepatic HCCs of arterial-phase gadoxetic acid-enhanced MR were not significantly improved by reducing the contrast injection rate to 0.5 mL/s compared with 1 mL/s.

Emergency Retrograde Endotracheal Intubation in a Child with Sublingual Teratoma and Congenital Tracheal Stenosis / 대한마취과학회지

Because of failure to intubate 2-year-old male patient suffering from respiratory difficulty due to sublingual mass (teratoma), emergent tracheostomy was planned. During induction with 100% oxygen and halothane with face mask, sudden cardiopulmonary arrest was occured. Circulation was resuscitated promptly but airway was not kept due to difficult intubation. So ventilation was proceeded through 16 gauge angiocatheter by cricothyroid membrane puncture and retrograde intubation was carried out with epidural catheter through another cricothyroid membrane puncture after then tracheostomy and removal of teratoma was carried out without event. But the patient has had severe dyspnea frequently in postoperative period. On postoperative 7th day, funnel shaped congenital tracheal stenosis was found with bronchogram. Therefore, we concluded that the post-tracheostomy respiratory problem was due to congenital tracheal stenosis. In conclusion, retrograde intubation is a valuable alternative for the emergent unexpected difficult intubation for adults or children because it has a high success rate, easy to learn, requires little practice and does not require complex apparatus. And the failure of a suitable tube to insert the trachea after it passed through the vocal cords or continuous dyspnea after intubation or tracheostomy be considered as the presence of airway narrowing and, possibly, congenital tracheal stenosis.