Venous Malformation in the Anterior Mediastinum.

Venous malformations (VMs) located in the anterior mediastinum are rare. Thus, diagnosis using imaging is often challenging, and they are typically diagnosed only after total tumor resection. Herein, we report a case of VM located in the anterior mediastinum diagnosed using computed tomography (CT) and magnetic resonance imaging (MRI). A 56-year-old woman presented for further evaluation of an anterior mediastinal mass observed during a chest CT. On CT, the mass was observed to have scattered calcifications and early and persistent enhancement with contrast material pooling dorsally in the delayed phase. On MRI, the mass was isointense on T1-weighted imaging and hyperintense on T2-weighted imaging without flow voids. From these images, we suspected the mass to be a VM, but the possibility of an arterial malformation/fistula could not be ruled out. Initially, a contrast material was injected via the arm, but to improve differentiation, it was also injected via the leg. The 4D-CT of the leg indicated no early enhancement of the mass; however, gradual enhancement was observed. This led to a definite diagnosis of VM. As she had no symptoms, we opted for a CT follow-up, and the mass remained stable for one year post-diagnosis. This case report underscores the usefulness of injecting contrast material through the leg in distinguishing VM from AVM/Fs in the anterior mediastinum.

Computed Tomography-guided Drainage with Modified Trocar Technique Using a Drainaway Drainage Kit.

Purpose: Image-guided percutaneous drainage for abscesses is known as a safe and effective treatment. The computed tomography-guided percutaneous drainage kit Drainaway (SB Kawasumi Co., Ltd.), developed on the basis of a modified trocar method, has made it possible to complete the procedure only under computed tomography guidance without radiographic fluoroscopy. This study investigated the feasibility and safety of Drainaway for abscess drainage. Material and Methods: In this retrospective observational study, 28 procedures in 27 patients (18 men and 9 women; age 67.0 ± 12.3 years) who underwent computed tomography-guided drainage using Drainaway between March and December 2021 at seven affiliated hospitals were analyzed. Patients with symptomatic, puncturable on computed tomography and refractory abscesses were included. Technical success (successful drainage with computed tomography alone), primary clinical success (successful drainage with Drainaway alone), secondary clinical success (avoidance of surgery), and complications were evaluated. Results: The sites of the abscesses were the intraperitoneal, retroperitoneal, and thoracic cavities in 19, 5, and 2 patients, respectively, and subcutaneous tissue in 1 patient. The mean size of the abscesses was 7.1 ± 3.4 cm. The technical success rate was 96.4%; the ligament of the puncture route could not be penetrated in one case. The primary clinical success rate was 77.8%, whereas the secondary clinical success rate of catheter upsizing or replacement was 96.3%. Complications included one case of biliary pleurisy that required drainage. Conclusions: Drainaway is a useful device that allows abscess drainage using only computed tomography guidance without radiographic fluoroscopy.

Can selective CT angiography reduce the incidence of severe complications during transcatheter arterial embolization or infusion chemotherapy for thoracic diseases?

PURPOSE: To evaluate the usefulness of selective computed tomography (CT) angiography in preventing severe complications, such as spinal cord injury and broncho- esophageal fistula, during the transcatheter arterial embolization or infusion chemotherapy for thoracic diseases. MATERIALS AND METHODS: Data from 28 patients with thoracic diseases were retrospectively analyzed in terms of selective CT angiography procedures carried out before transcatheter arterial embolization or transcatheter arterial infusion chemotherapy. RESULTS: There were no spinal cord injuries (0/13 and 0/15) or broncho-esophageal fistula developments (0/13 and 0/15) during transcatheter arterial embolization and transcatheter arterial infusion chemotherapy, respectively. CONCLUSION: We conclude that selective CT angiography is potentially useful for reducing the incidence of severe complications during transcatheter arterial embolization or infusion chemotherapy for thoracic diseases.

Questionnaire survey of acute and delayed adverse reactions to ferumoxides.

PURPOSE: The purpose of this study was to assess acute and delayed adverse reactions to ferumoxides. MATERIALS AND METHODS: 473 consecutive patients who underwent ferumoxides-enhanced MRI were enrolled in this study. Following non-contrast-enhanced MRI, patients were interviewed about their allergic history, and after ferumoxides-enhanced MRI, they were asked to fill out a questionnaire sheet to record any symptoms within one week. RESULTS: 345 of 473 questionnaires (72.9%) were returned. Fifty-eight of 345 patients (16.8%) showed some adverse reactions considered to be related to ferumoxides: 25 (7.2%) during administration, 25 (7.2%) later on the day of ferumoxides administration, and 17 (4.9%) within one week. Thirty-three patients (9.6%) showed only delayed adverse reactions. Delayed adverse reactions were more frequent in women than in men (p<0.01), and in patients with any allergic history than in those without such history (p<0.05). Acute adverse reactions tended to be more frequent in patients who had some adverse events to any contrast medium than in those with no such history (p=0.069). CONCLUSION: By using the questionnaire, the incidence of adverse reactions to ferumoxides (16.8%) was higher than previously reported from Japanese clinical trials.

Routine MR imaging protocol with breath-hold fast scans: diagnostic efficacy for focal liver lesions.

PURPOSE: To qualitatively and quantitatively evaluate the diagnostic efficacy of the breath-hold magnetic resonance (MR) imaging sequences in widespread clinical use for detection and characterization of focal hepatic lesions. MATERIALS AND METHODS: Fifty patients with 143 lesions [57 hepatocellular carcinomas (HCC), 10 borderline lesions, 18 metastatic tumors, 21 hemangiomas, and 37 cysts] underwent single-shot fast spin echo (SSFSE), fast spin echo (FSE), and gadolinium-enhanced dynamic fast spoiled gradient-recalled acquisition in steady state (FSPGR) breath-hold MR imaging of the liver. Alternative free receiver operating characteristic (AFROC) analysis was performed to independently and prospectively assess each sequence. RESULTS: For solid lesions, dynamic FSPGR allowed the most sensitive lesion detection and produced the highest lesion conspicuity and lesion-liver contrast-to-noise ratio (CNR). For non-solid benign lesions, SSFSE and FSE produced better results than dynamic FSPGR. SSFSE allowed the most sensitive detection and produced the best lesion conspicuity and lesion-liver CNR. CONCLUSION: SSFSE and dynamic FSPGR comprise the optimal imaging protocol for breath-hold MR assessment of focal hepatic lesions. This combination of sequences allows acquisition of critical diagnostic information about both inherent T2 and T1 lesion contrast and lesion vascularity.