Portal Vein Embolization: Radiological Findings Predicting Future Liver Remnant Hypertrophy.

OBJECTIVE. The purpose of this article is to evaluate the radiologic findings predicting the future liver remnant hypertrophy ratio after portal vein embolization of the right branch. MATERIALS AND METHODS. The associations between the radiologic findings and the future liver remnant hypertrophy ratio for 79 patients who underwent portal vein embolization of the right branch between July 2007 and April 2017 were retrospectively analyzed. Multiple linear regression was performed to adjust for potential confounders, and the volume ratio of the right lobe anterior segment, number of proximal small branches from the right anterior and posterior portal veins, transient hepatic parenchymal enhancement, portal vein invasion, and variants of main portal vein anatomy were evaluated. The potential confounders were age, ratio of future liver remnant hypertrophy to total liver volume, indocyanine green clearance rate, maximum serum total bilirubin before portal vein embolization, and history of chemotherapy. RESULTS. Statistically significant associations were found between the future liver remnant hypertrophy ratio and the number of proximal small branches from the right anterior and posterior portal veins (p < 0.001), transient hepatic parenchymal enhancement (p < 0.001), portal vein invasion (p = 0.017), and variants of main portal vein anatomy (p = 0.048). The mean future liver remnant hypertrophy rate was 51.0% (n = 16) in patients without the radiologic findings showing statistically significant differences, and 25.8% (n = 63) in patients with at least one significant finding. CONCLUSION. When added to previously reported factors, the radiologic findings identified can help determine the indications for portal vein embolization and novel strategies for major hepatectomy.

Enhancing precision in vascular embolization: evaluating the effectiveness of the intentional early detachment technique with detachable coils in complex cases.

BACKGROUND: This study aimed to assess the effectiveness and versatility of an intentional early detachment technique with detachable coils in addressing challenging vascular embolization scenarios. This novel approach aims to provide an alternative method for achieving precise coil placement when standard methods of detachable coil placement are ineffective owing to vascular anatomy or limited available equipment. MATERIALS AND METHODS: This retrospective study included 11 patients (nine males and two females; median age, 77 years) who underwent embolization procedures between October 2021 and December 2023 using the intentional early detachment technique through 1.6-Fr or 1.3-Fr microcatheters. In this technique, detachable coils were intentionally detached within the microcatheter and placed through saline flushing. The technique's technical success, complications, and clinical success were evaluated. RESULTS: The technique was applied in three distinct scenarios: tortuous vascular anatomy (four cases), inadequate system backup (three cases), and 1.3-Fr microcatheter use (four cases). The technical and clinical success rates were 100%. No complications were observed, and no cases of coil migration or malpositioning. CONCLUSION: The intentional early detachment technique is valuable for interventional radiologists and offers a solution for challenging vascular embolization scenarios. Its application is limited to specific circumstances; however, it can significantly enhance coil placement in complex cases, thereby contributing to improved patient care.

Foreign Body Granuloma After Embolization of Internal Iliac Artery Aneurysm Using N-Butyl-2-Cyanoacrylate: A Case Report.

Foreign body granulomas following endovascular treatment are rare complications and are mostly reported in the brain or cutaneous vascular tissues. To the best of our knowledge, no study to date has reported on foreign body granulomas in the abdomen after injection of N-butyl-2-cyanoacrylate (NBCA)-lipiodol mixture into the abdominal arteries. This study reports a case of foreign body granuloma that appeared 12 months after the embolization of a right internal iliac artery aneurysm using an NBCA-lipiodol mixture, which posed challenges in differentiation from malignant tumors. We present a 77-year-old man who underwent embolization of a right internal iliac artery aneurysm and open surgical repair of an abdominal aortic aneurysm. A contrast-enhanced CT performed 12 months postoperatively revealed a right-sided retroperitoneal mass surrounding the iliopsoas muscle. The mass contained multiple, small, hyperdense areas, suggesting the migration of the NBCA-lipiodol mixture casts from the embolized right internal iliac artery aneurysm. The differential diagnosis included foreign body granuloma, lymphoma, and sarcoma. A biopsy of the lesion revealed a granuloma with various stages of inflammation, no hemosiderin deposition, multinucleated giant cells, and foam cells containing fat, and was diagnosed with a foreign body granuloma. Special staining for microorganisms revealed no findings suggestive of infection. Because the patient was asymptomatic, no treatment was administered. Contrast-enhanced CT at 24 months postoperatively showed shrinkage of the mass, with no change in size noted at 48 months postoperatively. This report highlights a foreign body granuloma that mimicked malignant tumors. Extravascular migration of the NBCA-lipiodol mixture casts likely contributed to granuloma formation. Radiologists should consider foreign body granulomas after embolization using NBCA into the abdominal arteries.

Imaging findings of granulocyte colony-stimulating factor-producing tumors: a case series and review of the literature.

Granulocyte colony-stimulating factor (G-CSF)-producing tumors have an aggressive clinical course. Here, we report five cases of G-CSF-producing tumors and review the literature, focusing on imaging findings related to tumor-produced G-CSF. In addition to our cases, we identified 30 previous reports of G-CSF-producing tumors on which 18F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT, bone scintigraphy, or evaluation of bone marrow MR findings was performed. White blood cell count, serum C-reactive protein, and serum interleukin-6 were elevated in all cases for which these parameters were measured. G-CSF-producing tumors presented large necrotic masses (mean diameter 83.2 mm, range 17-195 mm) with marked FDG uptake (mean maximum standardized uptake value: 20.09). Diffuse FDG uptake into the bone marrow was shown in 28 of the 31 cases in which FDG-PET/CT was performed. The signal intensity of bone marrow suggested marrow reconversion in all seven MRI-assessable cases. Bone scintigraphy demonstrated no significant uptake, except in two cases with bone metastases. Splenic FDG uptake was increased in 8 of 10 cases in which it was evaluated. These imaging findings may reflect the effects of tumor-produced G-CSF. The presence of G-CSF-producing tumors should be considered in patients with cancer who show these imaging findings and marked inflammatory features of unknown origin.

Imaging findings of hemorrhagic hepatic cysts with enhancing mural nodules.

PURPOSE: This study aimed to evaluate the clinical and radiological findings of hemorrhagic hepatic cysts with enhancing mural nodules. METHODS: The radiology databases of five facilities were retrospectively searched for reports indicating hemorrhagic hepatic cysts or hepatic cystic tumors. Cases of hemorrhagic hepatic cysts with enhancing mural nodules based on pathological or radiological findings were identified and reviewed. RESULTS: We included 14 cases (11 female and 3 male) with a mean patient age of 72.6 years. Up until the enhancing mural nodules were detected, the cysts had decreased in size in all ten cases for which radiological imaging was available for a period of > 3 years previous to detection. Dynamic contrast-enhanced CT or MRI showed focal enhancement in the early phase and progressive centrifugal enhancement in the delayed phase in all 16 mural nodules ≥ 10 mm in diameter. Thirteen of 14 MRI assessable enhancing mural nodules ≥ 10 mm in diameter showed a hypointense rim with central hyperintensity on T2-weighted imaging. All cases showed calcification of the cyst wall. In the three referred cases, 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT demonstrated no intense FDG uptake in the enhancing mural nodules. In the four resected cases, histopathology of the enhancing mural nodules revealed neovascularization within an organized hematoma, including extensive dilated vessels and hemangioma-like lesions. CONCLUSIONS: Features including a decrease in cyst size, a progressive centrifugal enhancing pattern on dynamic contrast-enhanced CT or MRI, a hypointense rim with central hyperintensity on T2-weighted MRI, and cyst wall calcification may indicate a hemorrhagic hepatic cyst.

Arteriovenous fistula after robot-assisted laparoscopic prostatectomy: A rare case report.

INTRODUCTION: Arteriovenous fistula after radical prostatectomy is very uncommon. We report a rare case of pseudoaneurysm associated with arteriovenous fistula following robot-assisted laparoscopic prostatectomy. CASE PRESENTATION: A 67-year-old man diagnosed with prostatic adenocarcinoma underwent robot-assisted laparoscopic prostatectomy. He had a fever and lower abdominal pain with sign of peritoneal irritation, and his blood hemoglobin level dropped on postoperative day 11. Hemorrhage in the pelvic space with extravascular leakage was detected by contrast-enhanced computed tomography, and he underwent emergency angiography. An aneurysmal dilatation with early venous drainage was confirmed in a branch of the left internal iliac artery, and we diagnosed arteriovenous fistula. Transcatheter arterial embolization was performed, and the aneurysmal structure subsequently disappeared. CONCLUSION: Arteriovenous fistula may occur as a complication of robot-assisted laparoscopic prostatectomy. Transcatheter arterial embolization appears to be a useful and minimally invasive treatment.