Analysis of the Clinical Course in a Population of Patients with Biliary Tract Cancer Diagnosed as Unresectable After Portal Vein Embolization: A Case Series.

Portal vein embolization (PVE) is recommended as a preoperative procedure for patients with biliary tract cancer scheduled to undergo hepatic resection of more than 50%-60% of the liver. However, details and/or information regarding the follow-up of unresectable cases are often lacking, and the clinical course of unresectable cases is not well analyzed and reported. This study aimed to clarify the clinical prognosis of patients with unresectable biliary tract cancer after PVE. We retrospectively analyzed the clinical backgrounds of patients with biliary tract cancer who underwent PVE without subsequent resection between January 2011 and October 2022. Of the 21 patients with biliary tract cancer who underwent PVE during the study period, eight (38%) cases were unsuitable for resection after PVE for the following reasons: intraoperatively detected dissemination (n=2), para-aortic lymph node metastasis (n=1), liver metastasis (n=1), decreased liver function (n=2), development of liver metastasis while waiting (n=1), and insufficient residual liver volume (n=1). All patients received subsequent chemotherapy, including gemcitabine plus S-1 therapy in three cases, gemcitabine plus cisplatin plus S-1 in three cases, and gemcitabine plus cisplatin or S-1+cisplatin in one case each. As there is currently no curative treatment for biliary tract cancer other than surgery, multidisciplinary management and treatment of patient factors, including tumor factors and liver function, are essential to reducing the number of unresectable cases after PVE.

Assessment for Carotid Atherosclerotic Plaque Using Vessel Wall Magnetic Resonance Imaging: A Multireader ROC Study to Determine Optimal Sequence for Detecting Vessel Wall Calcification.

INTRODUCTION: We aimed to compare conventional vessel wall MR imaging techniques and quantitative susceptibility mapping (QSM) to determine the optimal sequence for detecting carotid artery calcification. METHODS: Twenty-two patients who underwent carotid vessel wall MR imaging and neck CT were enrolled. Four slices of 6-mm sections from the bilateral internal carotid bifurcation were subdivided into 4 segments according to clock position (0-3, 3-6, 6-9, and 9-12) and assessed for calcification. Two blinded radiologists independently reviewed a total of 704 segments and scored the likelihood of calcification using a 5-point scale on spin-echo imaging, FLASH, and QSM. The observer performance for detecting calcification was evaluated by a multireader, multiple-case receiver operating characteristic study. Weighted κ statistics were calculated to assess interobserver agreement. RESULTS: QSM had a mean area under the receiver operating characteristic curve of 0.85, which was significantly higher than that of any other sequence (p < 0.01) and showed substantial interreader agreement (κ = 0.68). A segment with a score of 3-5 was defined as positive, and a segment with a score of 1-2 was defined as negative; the sensitivity and specificity of QSM were 0.75 and 0.87, respectively. CONCLUSION: QSM was the most reliable MR sequence for the detection of plaque calcification.

A case of chylous ascites caused by reflux from the cisterna chyli to the disrupted common iliac lymphatic vessel: fluoroscopic records during intranodal lymphangiography.

A 40-year-old woman underwent laparoscopic common iliac lymphadenectomy for metastasis from rectal cancer. Two weeks after the surgery, she was found to have massive chylous ascites. After failure of conservative treatment, bilateral inguinal intranodal lymphangiography was performed. No definite extravasation was observed while lipiodol injected through the left inguinal node was ascending. When we punctured the right inguinal lymph nodes and started the injection of lipiodol, extravasation of diluted lipiodol was noted at the level of the first sacrum. Careful observation revealed that the ascending lipiodol became diluted in the cisterna chyli, refluxed through the median paraaortic route, leaked from the excised left common iliac lymph vessel, and flowed into the abdominal cavity. Lipiodol used in lymphangiography did not reduce chylous ascites at all. Twenty-seven days after lymphangiography, laparoscopic lymphatic ligation was performed, and the chylous ascites disappeared completely. CT obtained 40 days after surgical repair revealed disappearance of ascites and enlargement of the thoracic duct, which had not been observed on preoperative lymphangiography. Notably, lymphatic reflux from the cisterna chili can occur without obstruction of the thoracic duct and may result in chylous ascites.

Amide Proton Transfer-Chemical Exchange Saturation Transfer Imaging of Intracranial Brain Tumors and Tumor-like Lesions: Our Experience and a Review.

Chemical exchange saturation transfer (CEST) is a molecular magnetic resonance imaging (MRI) method that can generate image contrast based on the proton exchange between labeled protons in solutes and free, bulk water protons. Amide proton transfer (APT) imaging is the most frequently reported amide-proton-based CEST technique. It generates image contrast by reflecting the associations of mobile proteins and peptides resonating at 3.5 ppm downfield from water. Although the origin of the APT signal intensity in tumors is unclear, previous studies have suggested that the APT signal intensity is increased in brain tumors due to the increased mobile protein concentrations in malignant cells in association with an increased cellularity. High-grade tumors, which demonstrate a higher proliferation than low-grade tumors, have higher densities and numbers of cells (and higher concentrations of intracellular proteins and peptides) than low-grade tumors. APT-CEST imaging studies suggest that the APT-CEST signal intensity can be used to help differentiate between benign and malignant tumors and high-grade gliomas and low-grade gliomas as well as estimate the nature of lesions. In this review, we summarize the current applications and findings of the APT-CEST imaging of various brain tumors and tumor-like lesions. We report that APT-CEST imaging can provide additional information on intracranial brain tumors and tumor-like lesions compared to the information provided by conventional MRI methods, and that it can help indicate the nature of lesions, differentiate between benign and malignant lesions, and determine therapeutic effects. Future research could initiate or improve the lesion-specific clinical applicability of APT-CEST imaging for meningioma embolization, lipoma, leukoencephalopathy, tuberous sclerosis complex, progressive multifocal leukoencephalopathy, and hippocampal sclerosis.

Percutaneous Direct Puncture of Retropancreatic Splenic Vein and Portal Thrombectomy in a Patient With Liver Transplantation and Simultaneous Splenectomy.

Portal vein thrombosis following liver transplantation is generally managed by endovascular treatment. Although several techniques are available for portal venous access, trans-splenic access is of interest because it avoids damage to the liver graft. However, the spleen cannot be punctured to access the portal vein after splenectomy. We herein report a case of portal vein thrombosis following living donor liver transplantation with simultaneous splenectomy successfully treated by percutaneous intervention with direct puncture of the retropancreatic splenic vein. The splenic vein was punctured under computed tomography guidance in the prone position. Portal venography revealed a contrast defect due to a thrombus in the extrahepatic to intrahepatic portal vein. The portal vein was reopened after thrombectomy, and the portal vein thrombosis did not recur for 2 y. The technique and advantages of our approach are described.

Significance of Low Signal in Intracranial Vertebral Artery Wall Observed on Susceptibility-Weighted Angiography.

PURPOSE: We aimed to investigate the clinical significance of the low signal in the intracranial vertebral artery wall observed on susceptibility-weighted angiography. MATERIALS AND METHODS: We retrospectively reviewed susceptibility-weighted angiographies from 200 consecutive patients with acute ischemic stroke in the posterior circulation territory. The presence of eccentric or concentric low signals in the vertebral artery wall was examined and evaluated. The etiology of the low signal was also investigated as much as possible by referring to computed tomography and T1-weighted imaging (T1WI). We also compared its frequency in each stroke subtype. RESULTS: A low signal was observed in 128/200 patients (64%). The low signals (58%) corresponded to vessel wall calcification in 74 of 128 patients and to vessel wall thickening showing intermediate to low (n = 8) or high (n = 16) signals on T1WI in 24 (19%) patients. The low signal did not have vessel wall thickening or calcification in 1 patient, and the cause of the low signal could not be verified in 29 patients. According to stroke subtypes, a low signal was observed in 14/14 (100%) vertebral artery dissections, all of which corresponded to intramural hematoma. A low signal was observed in 51/65 (78%) atherothromboses, which were significantly more frequent than cardioembolism (34/66; 52%) and small-artery disease (18/39; 46%) (p < 0.01). In atherothrombosis, calcification was the most common cause of low signal (n = 32; 63%). CONCLUSION: Low signals on susceptibility-weighted angiography were frequently observed in vertebral artery dissection and atherothrombosis, reflecting intramural hematoma in all of the former and predominantly calcification in the latter.

Hepatic sclerosing haemangioma showing restricted diffusion: A case report with histopathologic correlation.

Hepatic sclerosing haemangiomas are rare benign tumours that are often difficult to distinguish from malignant tumours because these tumours do not show the typical imaging features of cavernous haemangiomas. We report a case of a sclerosing haemangioma that showed restricted diffusion and was difficult to differentiate from a malignancy. A 60-year-old female was referred to our hospital for evaluation of a hepatic mass that was incidentally diagnosed after a CT scan for right lower quadrant abdominal pain. Contrast-enhanced dynamic CT showed hepatic capsular retraction, with a small peripheral enhancement of the mass. The lesion appeared homogeneously hypointense on T1W images, heterogeneously hyperintense on T2W images, hyperintense on diffusion-weighted images, and hypointense on apparent diffusion coefficient (ADC) map. The lesion was suspected to be a cholangiocellular carcinoma and was surgically resected, but a final diagnosis of hepatic sclerosing haemangioma was made. Hepatic sclerosing/sclerosed haemangiomas are usually considered to show an increased ADC, which is useful for distinguishing them from malignant tumours. However, in this particular case, most of the lesion contained many obliterated or narrowed vascular channels, which might have acted as septa restricting the diffusion of water molecules in the intervening fibrous and/or hyalinised tissue. Hepatic sclerosing haemangiomas in the process of becoming completely fibrotic may show restricted diffusion, similar to malignant tumours.

Amide proton transfer MRI differentiates between progressive multifocal leukoencephalopathy and malignant brain tumors: a pilot study.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nerve system caused by the John Cunningham virus. On MRI, PML may sometimes appear similar to primary central nervous system lymphoma (PCNSL) and glioblastoma multiforme (GBM). The purpose of this pilot study was to evaluate the potential of amide proton transfer (APT) imaging for differentiating PML from PCNSL and GBM. METHODS: Patients with PML (n = 4; two men; mean age 52.3 ± 6.1 years), PCNSL (n = 7; four women; mean age 74.4 ± 5.8 years), or GBM (n = 11; 6 men; mean age 65.0 ± 15.2 years) who underwent APT-CEST MRI between January 2021 and September 2022 were retrospectively evaluated. Magnetization transfer ratio asymmetry (MTRasym) values were measured on APT imaging using a region of interest within the lesion. Receiver operating characteristics curve analysis was used to determine diagnostic cutoffs for MTRasym. RESULTS: The mean MTRasym values were 0.005 ± 0.005 in the PML group, 0.025 ± 0.005 in the PCNSL group, and 0.025 ± 0.009 in the GBM group. There were significant differences in MTRasym between PML and PCNSL (P = 0.023), and between PML and GBM (P = 0.015). For differentiating PML from PCNSL, an MTRasym threshold of 0.0165 gave diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of 100% (all). For differentiating PML from GBM, an MTRasym threshold of 0.015 gave diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 90.9%, 80.0%, and 100%, respectively. CONCLUSION: MTRasym values obtained from APT imaging allowed patients with PML to be clearly discriminated from patients with PCNSL or GBM.

Combined Transhepatic and Transsplenic Recanalization of Chronic Portal Vein Occlusion to Treat Jejunal Varices: A Report of Two Cases.

We report two cases of chronic portal vein occlusion with jejunal varices successfully treated using percutaneous intervention with a combined transhepatic and transsplenic approach. Case 1 was a 60-year-old man with uncontrolled jejunal variceal bleeding, and case 2 was a 79-year-old man with anastomotic jejunal variceal bleeding and cholangitis. Single access via the transhepatic or transsplenic route failed to allow catheter advancement through the occlusion. After introducing pull-through access via the transhepatic and transsplenic routes, a metallic stent was could be used to dilate the occluded portal vein. Anastomotic jejunal varices functioning as hepatopetal collaterals were embolized after the establishment of antegrade portal flow. No symptom relapse was observed during the follow-up period (31 months for case 1 and 34 months for case 2).

Quantitative Chemical Exchange Saturation Transfer Imaging of Amide Proton Transfer Differentiates between Cerebellopontine Angle Schwannoma and Meningioma: Preliminary Results.

Vestibular schwannomas are the most common tumor at the common cerebellopontine angle, followed by meningiomas. Differentiation of these tumors is critical because of the different surgical approaches required for treatment. Recent studies have demonstrated the utility of amide proton transfer (APT)-chemical exchange saturation transfer (CEST) imaging in evaluating malignant brain tumors. However, APT imaging has not been applied in benign tumors. Here, we explored the potential of APT in differentiating between schwannomas and meningiomas at the cerebellopontine angle. We retrospectively evaluated nine patients with schwannoma and nine patients with meningioma who underwent APT-CEST MRI from November 2020 to April 2022 pre-operation. All 18 tumors were histologically diagnosed. There was a significant difference in magnetization transfer ratio asymmetry (MTRasym) values (0.033 ± 0.012 vs. 0.021 ± 0.004; p = 0.007) between the schwannoma and meningioma groups. Receiver operative curve analysis showed that MTRasym values clearly differentiated between the schwannoma and meningioma groups. At an MTRasym value threshold of 0.024, the diagnostic sensitivity, specificity, positive predictive value, and negative predictive values for MTRasym were 88.9%, 77.8%, 80.0%, and 87.5%, respectively. Our results demonstrated the ability of MTRasym values on APT-CEST imaging to discriminate patients with schwannomas from patients with meningiomas.

Long-term outcomes of living-donor liver transplantation, hepatic resection, and local therapy for hepatocellular carcinoma with three <3-cm nodules in a single institute.

Background and Aim: Treatment for small hepatocellular carcinoma (HCC) is determined based on the results of a liver function test and the tumor location and spread. The present study compared the outcomes among local therapy, hepatic resection (HR), and living-donor liver transplantation (LDLT) for small HCC in a single institute. Methods: We compared the overall survival, recurrence-free survival, and cancer-specific survival rates in patients with three HCC nodules <3 cm in size among local therapy, which included radiofrequency ablation (RFA), percutaneous ethanol injection (PEI), and transarterial chemoembolization (TACE), and surgical treatment (HR and LDLT). Results: One hundred and ninety-seven patients with local therapy (109 RFA, 26 PEI, and 78 TACE), 107 with HR, and 66 with LDLT were enrolled in this study. There was no significant difference in OS among these groups. The recurrence-free, cancer-specific survival (CSS) of LDLT was superior to local therapy and HR. The prognostic factors for the survival were Child-Pugh (CP) Grade B and tumor marker for local therapy and multiple tumors and elevated ALT levels for HR. Conclusions: For CP grade B patients with HCC of three <3-cm nodule, LDLT could be considered because it resulted in better survival and CSS rates than local therapy.

Successful pulmonary artery stenting for occlusion at a constructed pericardial conduit after right upper double sleeve lobectomy.

The patient was a 53-year-old man. His chief complaint was a cough and dyspnea on exertion. Computed tomography (CT) showed a 3-cm-diameter tumor in the right upper lobe with invasion from hilar lymph nodes to the superior vena cava, right main bronchus, and pulmonary artery. After being diagnosed with non-small cell lung cancer, the patient underwent preoperative induction radiochemotherapy. At surgery, right upper double sleeve lobe lobectomy was performed. The right main pulmonary artery was reconstructed using a pericardial conduit. CT 1 week after surgery showed impaired blood flow in the right pulmonary artery. A metal vascular stent was inserted into the narrow part of the constructed pulmonary artery in the hybrid operating room because thrombectomy was unsuccessful. After surgery, contrast CT showed that blood flow was maintained. The patient is currently well without any recurrence 3 years after surgery.

Successful retrograde transvenous embolization under balloon occlusion for rectal arteriovenous malformation.

A 57-year-old man was admitted to our hospital because of frequent hematochezia. Colonoscopy exhibited a submucosal tumor-like lesion in the lower rectum. Abdominal contrast-enhanced computed tomography showed a rectal arteriovenous malformation (AVM) on the right side wall of the lower rectum. The feeder was the superior rectal artery, with early venous return. Embolization of the draining vein and feeding artery of the AVM with N-butyl-2-cyanoacrylate under balloon occlusion was planned. Angiography of the superior rectal artery showed the nidus in the rectum with early venous return of contrast material. The portal vein was punctured percutaneously under ultrasound guidance, and a balloon catheter advanced to the distal part of the superior rectal vein. Venography under balloon occlusion showed the outflow vein and nidus. Transvenous and transarterial nidus embolization with N-butyl-2-cyanoacrylate under balloon occlusion was then performed. Since the embolization, there have been no further episodes of bleeding. There is no established treatment for AVMs. Successful treatment requires targeting and eradication of the nidus. We successfully performed embolization therapy for a rectal AVM via a retrograde transvenous approach. This technique may be suitable for completely eradicating the nidus without the risk of embolism.

Inferior Vena Cava Anomalies with Portal Vein System Continuation Presenting as Portal Hypertension with a Long-term Follow-up.

Inferior vena cava (IVC) anomalies, such as the absence of an intra-hepatic IVC or IVC hypoplasia, are rare. Usually, these anomalies are asymptomatic and cause few clinical issues. We herien report a 53-year-old woman with IVC anomalies who demonstrated both azygos and portal vein system continuation. Over time, this resulted in gradually progressive portal hypertension due to abnormal hemodynamics. The increased inflow from the IVC to the portal vein system for an extended time may contribute to the development of portal hypertension without liver cirrhosis.

Intractable Hepatic Encephalopathy with a Large Portosystemic Shunt Successfully Treated Using Shunt-preserving Disconnection of the Portal and Systemic Circulation.

Hepatic encephalopathy (HE) is a significant symptom of decompensated liver cirrhosis. Occlusion of portosystemic shunts is used to treat refractory HE. Nevertheless, these treatments often cause adverse events, such as ascites and esophageal varices. We treated a 57-year-old man with refractory HE using shunt-preserving disconnection of the portal and systemic circulation (SPDPS). After SPDPS, there were no obvious complications, and the patient's ammonia level significantly decreased. To date, the patient has not experienced recurrent HE. SPDPS appears to be a safe and effective treatment method for portosystemic encephalopathy.

Quantitative Susceptibility Mapping for Carotid Atherosclerotic Plaques: A Pilot Study.

PURPOSE: Identifying plaque components such as intraplaque hemorrhage, lipid rich necrosis, and calcification is important to evaluate vulnerability of carotid atherosclerotic plaque; however, conventional vessel wall MR imaging may fail to discriminate plaque components. We aimed to evaluate the components of plaques using quantitative susceptibility mapping (QSM), a newly developed post-processing technique to provide voxel-based quantitative susceptibilities. METHODS: Seven patients scheduled for carotid endarterectomy were enrolled. Magnitude and phase images of five-echo 3D fast low angle shot (FLASH) were obtained using a 3T MRI, and QSM was calculated from the phase images. Conventional carotid vessel wall images (black-blood T1-weighted images [T1WI], T2-weighted images [T2WI], proton-density weighted images [PDWI], and time-of-flight images [TOF]) were also obtained. Pathological findings including intraplaque hemorrhage, calcification, and lipid rich necrosis at the thickest plaque section were correlated with relative susceptibility values with respect to the sternocleidomastoid muscle on QSM. On conventional vessel wall images, the contrast-noise ratio (CNR) between the three components and sternocleidomastoid muscle was measured respectively. Wilcoxon signed-rank test analyses were performed to assess the relative susceptibility values and CNR. RESULTS: Pathologically, lipid rich necrosis was proved in all of seven cases, and intraplaque hemorrhage in five of seven cases. Mean relative susceptibility value of hemorrhage was higher than lipid rich necrosis unexceptionally (P = 0.0313). There were no significant differences between CNR of hemorrhage and lipid rich necrosis on all sequences. In all six cases with plaque calcification, susceptibility value of calcification was significantly lower than lipid rich necrosis unexceptionally (P = 0.0156). There were significant differences between CNRs of lipid rich necrosis and calcification on T1WI, PDWI, TOF (P < 0.05). CONCLUSION: QSM of carotid plaque would provide a novel quantitative MRI contrast that enables reliable differentiation among intraplaque hemorrhage, lipid rich necrosis, and calcification, and be useful to identify vulnerable plaques.

Treatment of Periorbital and Palpebral Arteriovenous Malformations.

Objectives: To clarify clinically challenging palpebral arteriovenous malformations (AVMs) and to propose a novel therapeutic modality, we developed a multi-disciplinary approach for the management of AVMs with ulcer. Approach: First, the central retinal artery was secured with embolization by the transophthalmic arterial, a terminal branch of the internal carotid artery (ICA), and then, the branches of the external carotid artery (ECA) were embolized to cause a response in the AVM vasculature followed by sclerotherapy and surgery. Results: Over a 3-year follow-up of palpebral and periorbital AVMs in four females and one male 20 to 50 years of age with a mean age of 38 years, complete remission of the lesions were seen with no major complication, such as blindness, ptosis, or cerebral infarction, with functionally sound and esthetically acceptable results, with no recurrence or worsening even with one case of ulceration postembolization. Innovation: Planned treatment of palpebral and periorbital AVMs, which have been often left untreated because of their complex vasculature and a risk of total blindness due to occlusion of the central retinal artery. A "wait-and-watch" approach is frequently taken. It is important to secure the periphery to the bifurcation of the central retinal artery of the ICA, and then, embolization through the ECA results in complete remission of the lesion, followed by sclerotherapy and surgery, which are successful both in terms of function and esthetics. Conclusion: First, securing the central retinal artery leads to safer and complete resolution of palpebral and periorbital AVMs; wounding or therapeutic complications such as skin necrosis may be seen, but this approach results in complete remission in 3 years with no major complications.

Cerebral lipiodol embolism related to a vascular lake during chemoembolization in hepatocellular carcinoma: A case report and review of the literature.

A male patient underwent conventional transcatheter chemoembolization for advanced recurrent hepatocellular carcinoma (HCC). Even after the injection of 7 mL of lipiodol followed by gelatin sponge particles, the flow of feeding arteries did not slow down. A repeat angiography revealed a newly developed vascular lake draining into systemic veins; however, embolization was continued without taking noticing of the vascular lake. The patient's level of consciousness deteriorated immediately after the procedure, and non-contrast computed tomography revealed pulmonary and cerebral lipiodol embolisms. The patient's level of consciousness gradually improved after 8 wk in intensive care. In this case, a vascular lake emerged during chemoembolization and drained into systemic veins, offering a pathway carrying lipiodol to pulmonary vessels, the most likely cause of this serious complication. We should be aware that vascular lakes in HCC may drain into systemic veins and can cause intratumoral arteriovenous shunts.