Journal of the Korean Society of Radiology最新文献

Patients with portal hypertension who have undergone stoma surgery are at risk of developing stomal varices, which can occasionally lead to bleeding. Recurrent stomal bleeding can be life-threatening; however, the optimal treatment for this condition remains unestablished due to the rarity of such varices. We report a case of a 73-year-old man with liver cirrhosis and a history of abdominoperineal resection with colostomy for rectal cancer, in whom stomal variceal bleeding was successfully treated with coil embolization and sclerotherapy via a direct percutaneous approach to the afferent vein. No re-bleeding occurred within 3 months of follow-up, and no serious complications were observed. We propose that coil embolization combined with sclerotherapy via a direct percutaneous approach is a feasible and effective treatment option for bleeding stomal varices in patients with decompensated cirrhosis.

Prostate specific antigen (PSA) is a crucial tool for detecting and monitoring of prostate cancer, and elevated levels of PSA often indicate disease progression. Higher PSA levels are generally associated with more aggressive cancers and an increased risk of cancer-specific mortality. In this report, we present an unusual case of primary aggressive prostate cancer characterized by unexpectedly low PSA levels, despite the presence of multiple lumbar bone metastases at the time of diagnosis. It is extremely uncommon to have a low PSA level at the time of initial prostate cancer diagnosis, especially in cases that are non-recurrent, and even more so for adenocarcinomas without neuroendocrine differentiation. This report highlights the challenges in accurately diagnosing disease using CT and MRI findings when confronted with atypically low PSA patterns, necessitating invasive diagnostic approaches such as transperineal biopsy following abdominoperineal resection in a patient with a colostomy.

Purpose: In this retrospective study, we aimed to assess the efficacy of artificial intelligence-based computer-aided detection (AI-CAD) for breast cancer detection on mammograms.

Materials and methods: Mammograms from 269 women with breast cancer were analyzed. Cancer visibility was determined based on reports from experienced radiologists. Two expert radiologists assessed mammographic findings and breast imaging reporting and data system (BI-RADS) categories by consensus for cases of visible cancer. AI-CAD results were reviewed to determine whether AI-CAD correctly marked the cancer site. AI-CAD detection rates were analyzed according to mammographic findings, BI-RADS categories, lesion size, histologic grade, lymph node involvement, and stage. The concordance between the findings of AI-CAD and those of experienced radiologists was also assessed. Mammographically occult cases were defined as those with negative mammographic findings by two radiologists.

Results: AI-CAD detected 81.4% (219/269) of cancers, with higher detection rates occurring for larger lesion sizes, high histologic grades, lymph node involvement, and advanced stages. AI-CAD detection rates were higher for architectural distortion, mass, and calcification, but lower for asymmetry. Detection rates increased with higher BI-RADS categories and a higher number of mammography findings. Concordance between the assessment of AI-CAD and that of experienced radiologists was 88.5% (238/269). AI-CAD correctly detected 19.4% (6/31) of mammographically occult cases.

Conclusion: AI-CAD detected 81.4% of cancers, with substantial concordance with the findings of experienced radiologists. It correctly identified 19.4% of mammographically occult cases.

Pancreatic neuroendocrine tumors (PanNETs) are a rare type of pancreatic neoplasm. PanNETs with intraductal growth are considered extremely rare, and ductal involvement in NETs has been reported to correlate with aggressive clinical behavior. A 67-year-old male was referred to our hospital for further evaluation of a pancreatic tumor. Various imaging modalities, including ultrasonography, contrast-enhanced CT, MRI, and endoscopic ultrasonography (EUS), demonstrated a well-defined pancreatic mass in the head and body, primarily located within the main pancreatic duct with extension to the main portal vein. Histological diagnosis from an EUS-guided biopsy revealed a grade 3 well-differentiated NET. The patient was scheduled for surgery; however, multiple additional bone metastases were identified on ¹⁸F-fluorodeoxyglucose PET/CT. Although the presence of intraductal growth and portal vein invasion is uncommon in PanNETs, aggressive workup and treatment are essential in such cases.

The femoral vein is frequently used for central venous access during extracorporeal membrane oxygenation (ECMO). Accidental cannulation of the ascending lumbar vein (ALV) during ECMO has rarely been reported. Hemorrhage related to venous rupture, or solid organ injury can occur depending on the course of the large-bore catheter. Ultrasonographic or fluoroscopic guidance helps ensure correct placement. Nevertheless, if accidental cannulation occurs, endovascular management can be considered a treatment option. We present the case of a 78-year-old man with an ECMO catheter malpositioned through the left ALV, which was removed with tract embolization.

In liver and pancreatobiliary MRI, mitigating respiratory motion-related artifacts has always been a major challenge in image acquisition. Motion reduction by breathing control schemes or scan time acceleration by k-space undersampling are two accessible approaches in clinical imaging. Parallel imaging is an indispensable everyday technique with well-known characteristics, but with drawbacks that limit acceleration factors to ≤4. Compressed sensing exploits the data sparsity of MR images, and pseudorandomly undersamples k-space data to iteratively reconstruct images using sophisticated complex computations within highly accelerated scanning time. Albeit, this is with long reconstruction time and complexity in parameter optimization. Deep learning reconstruction uses pretrained and validated convolutional neural networks to reconstruct undersampled data, with the main tasks being image acceleration, denoising, and superresolution. While promising, deep learning reconstruction requires further testing and practical experience with model stability, generalizability, and output image fidelity.

Hepatocellular carcinoma (HCC) is a heterogeneous tumor with variable prognosis, even among patients at a similar tumor stage. Therefore, identifying prognostic features prior to treatment can help select the best therapeutic approach and ultimately optimize patient survival. While many imaging features on MRI have been suggested to have prognostic potential, some have emerged as critical imaging biomarkers, and efforts are underway to define and standardize relevant terminology. In this article, we comprehensively review MRI imaging features of HCC with prognostic potential.

Arteriovenous fistulas (AVFs) involving the middle meningeal artery (MMA) and middle meningeal vein were initially described in 1951. Middle meningeal arteriovenous fistulas (MMAVFs) are rare abnormalities classified as dural AVFs, connecting the MMA to the nearby dural venous sinus or cortical veins. Clinical symptoms of MMAVFs include pulsatile tinnitus, headache, exophthalmos, chemosis, and diplopia. Moreover, MMAVFs pose the risk of catastrophic cerebral hemorrhage. Previous studies have suggested that endovascular embolization using coils or other embolic materials produces acceptable outcomes including symptom relief and bleeding prevention. We present a case of traumatic MMAVF in a 27-year-old male with pulsatile tinnitus. The MMAVF was eliminated via endovascular transarterial embolization using a coil, without any residual symptoms or complications. These results suggest that endovascular embolization may be effective in managing MMAVF.