Management for iatrogenic femoral pseudoaneurysms by embolisation of the aneurysmal neck from the contralateral femoral artery: A report of five cases.

Femoral pseudoaneurysms are typically associated with femoral arterial catheterisation. Treating iatrogenic morbidity requires curing the disease, without causing any additional complications. Occlusion of the aneurysmal neck is ideal to seal post-catheterised pseudoaneurysms along with maintaining the femoral arterial flow. However, few reports have suggested neck embolisation for post-catheterised pseudoaneurysms. We describe five cases of iatrogenic femoral pseudoaneurysms in patients successfully treated with embolisation through the aneurysmal neck. This technique may be an alternative therapeutic option in managing femoral pseudoaneurysms.

Improved Diagnosis of Adjacent Organ Invasion of Extrahepatic Cholangiocarcinoma by Adding Arterial and Delayed Phases.

PURPOSE: To clarify the role of dynamic computed tomography (CT) in diagnosing extrahepatic cholangiocarcinoma (eCCA) involving adjacent organs. MATERIAL AND METHODS: We retrospectively analyzed patients diagnosed with eCCA in Iwate Medical University Hospital (Morioka, Japan) during January 2011-December 2021 who underwent dynamic contrast-enhanced CT before biliary intervention, surgery, or chemotherapy. For surgical cases, two radiologists independently reviewed CT images in the portal, dual (adding arterial phase), and triple (adding delayed phase) phases. The mean attenuations of the abdominal aorta, portal vein (PV), hepatic parenchyma, pancreatic parenchyma, and eCCA were measured. The biliary segment-wise longitudinal tumour extent, arterial and PV invasion, organ invasion (liver, pancreas, and duodenum), and regional lymph node metastasis were assessed on a five-point scale. Image performances were compared using the sensitivity, specificity, and area under the curve (AUC). RESULTS: We included 120 patients (mean age, 71.7 ± 8.9; 84 males). The PV and liver differed most from the bile duct tumour in the portal phase. The abdominal aorta and pancreas differed most from eCCA in the arterial phase. For 80 patients evaluated on the five-point scale, adding phases increased the AUC for pancreatic, duodenal, and arterial invasion for each observer (observer 1, 0.79-0.93, p<0.01, 0.71-0.86, p = 0.04, 0.74-0.99, p = 0.02; observer 2, 0.88-0.96, p = 0.01, 0.73-0.94, p<0.01, 0.80-0.99 p = 0.04; respectively). The AUC for biliary segment-wise longitudinal tumor extent, hepatic, and PV invasion remained unchanged with additional phases. CONCLUSIONS: Portal-phase information is sufficient to evaluate the segmental extent of bile duct and liver/PV invasion. Arterial- and delayed-phase information can help evaluate pancreatic, duodenal, and arterial invasion.

Deep learning reconstruction allows low-dose imaging while maintaining image quality: comparison of deep learning reconstruction and hybrid iterative reconstruction in contrast-enhanced abdominal CT.

We aimed to compare the radiation dose and image quality of a low-dose abdominal computed tomography (CT) protocol reconstructed with deep learning reconstruction (DLR) with those of a routine-dose protocol reconstructed with hybrid-iterative reconstruction. This retrospective study enrolled 71 patients [61 men; average age, 71.9 years; mean body mass index (BMI), 24.3 kg/m2] who underwent both low-dose abdominal CT with DLR [advanced intelligent clear-IQ engine (AiCE)] and routine-dose abdominal CT with hybrid-iterative reconstruction [adaptive iterative dose reduction 3D (AIDR 3D)]. Radiation dose parameters included volume CT dose index (CTDIvol), effective dose (ED), and size-specific dose estimate (SSDE). Mean image noise and contrast-to-noise ratio (CNR) were calculated. Image noise was measured in the hepatic parenchyma and bilateral erector spinae muscles. Moreover, subjective assessment of perceived image quality and diagnostic acceptability was performed. The low-dose protocol helped reduce the CTDIvol by 44.3%, ED by 43.7%, and SSDE by 44.9%. Moreover, the noise was significantly lower and CNR significantly higher with the low-dose protocol than with the normal-dose protocol (P<0.001). In the subjective assessment of image quality, there was no significant difference between the protocols with regard to image noise. Overall, AiCE was superior to AIDR 3D in terms of diagnostic acceptability (P=0.001). The use of AiCE can reduce overall radiation dose by more than 40% without loss of image quality compared to routine-dose abdominal CT with AIDR 3D.

A case of hepatic intraductal papillary neoplasm of the bile duct.

In this report, we present a 57-year-old female with a history of mild alcoholic liver disease during a medical check-up. Abdominal computed tomography and magnetic resonance imaging showed a multicystic mass with a solid enhancing mural nodule in the right lobe of the liver. Subsequently, laparoscopic right liver lobectomy was performed and pathological findings revealed intraductal papillary neoplasm of the bile duct (IPNB) with an associated invasive carcinoma. IPNB is a relatively rare disease that should be considered in the differential diagnosis of hepatic cystic tumours. Our case report highlights the importance of capturing image findings of the IPNB as this disease has a high potential for malignancy.

Superior objective and subjective image quality of deep learning reconstruction for low-dose abdominal CT imaging in comparison with model-based iterative reconstruction and filtered back projection.

OBJECTIVE: This study aimed to conduct objective and subjective comparisons of image quality among abdominal computed tomography (CT) reconstructions with deep learning reconstruction (DLR) algorithms, model-based iterative reconstruction (MBIR), and filtered back projection (FBP). METHODS: Datasets from consecutive patients who underwent low-dose liver CT were retrospectively identified. Images were reconstructed using DLR, MBIR, and FBP. Mean image noise and contrast-to-noise ratio (CNR) were calculated, and noise, artifacts, sharpness, and overall image quality were subjectively assessed. Dunnett's test was used for statistical comparisons. RESULTS: Ninety patients (67 ± 12.7 years; 63 males; mean body mass index [BMI], 25.5 kg/m2) were included. The mean noise in the abdominal aorta and hepatic parenchyma of DLR was lower than that in FBP and MBIR (p < .001). For FBP and MBIR, image noise was significantly higher for obese patients than for those with normal BMI. The CNR for the abdominal aorta and hepatic parenchyma was higher for DLR than for FBP and MBIR (p < .001). MBIR images were subjectively rated as superior to FBP images in terms of noise, artifacts, sharpness, and overall quality (p < .001). DLR images were rated as superior to MBIR images in terms of noise (p < .001) and overall quality (p = .03). CONCLUSIONS: Based on objective and subjective comparisons, the image quality of DLR was found to be superior to that of MBIR and FBP on low-dose abdominal CT. DLR was the only method for which image noise was not higher for obese patients than for those with a normal BMI. ADVANCES IN KNOWLEDGE: This study provides previously unavailable information on the properties of DLR systems and their clinical utility.