"Speckled Enhancement" on Gd-EOB-DTPA Enhanced MR Imaging of Primary Hepatic Mucosa-associated Lymphoid Tissue Lymphoma.

PURPOSE: To elucidate MRI features of primary hepatic mucosa-associated lymphoid tissue (MALT) lymphoma, particularly, the "speckled enhancement" on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI. METHODS: The institutional review board approved this retrospective observational study and waived informed consent. Using our picture archiving and communication systems and electronic medical records, five patients histopathologically diagnosed as hepatic MALT lymphoma and clinically confirmed as primary lesions who had undergone dynamic contrast-enhanced (DCE)-CT and DCE-MRI with Gd-EOB-DTPA were identified from September 2009 to December 2020. Two radiologists assessed their CT and MRI data in consensus with a pathologist's advice. RESULTS: Overall, five lesions in five patients were included in this study. Precontrast CT showed hypoattenuation in all lesions. In the arterial phase of DCE-CT, four lesions (80%) showed hyperattenuation, whereas all lesions showed iso- to hypoattenuation in the delayed phase. A vessel penetration sign was also observed in all lesions. On MRI, all lesions showed hypointensity on T1-weighted images, hyperintensity on T2-weighted images, and restricted diffusion on diffusion-weighted images. Both DCE-CT and DCE-MRI with Gd-EOB-DTPA showed similar enhancement patterns, except for the hepatocyte phase. Notably, however, four out of five lesions showed characteristic "speckled enhancement" that refers to punctate positive enhancements within the low signal lesions on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI pathologically confirmed to be hepatocyte clusters that remained in the tumor. CONCLUSION: Primary hepatic MALT lymphomas were characterized by arterial phase enhancement, restricted diffusion, vessel penetration sign, and more specifically "speckled enhancement" in the hepatobiliary phase of DCE-MRI with Gd-EOB-DTPA.

Postendovascular Aneurysmal Repair Increase in Local Energy Loss for Fusiform Abdominal Aortic Aneurysm: Assessments With 4D flow MRI.

BACKGROUND: Although endovascular aneurysmal repair (EVAR) is a preferred treatment for abdominal aortic aneurysm (AAA) owing to its low invasiveness, its impact on the local hemodynamics has not been fully assessed. PURPOSE: To elucidate how EVAR affects the local hemodynamics in terms of energy loss (EL). STUDY TYPE: Prospective single-arm study. FIELD STRENGTH/SEQUENCE: A 3.0 T/4D flow MRI using a phase-contrast three-dimensional cine-gradient-echo sequence. POPULATION: A total of 13 consecutive patients (median [interquartile range] age: 77.0 [73.0, 78.8] years, 11 male) scheduled for EVAR as an initial treatment for fusiform AAA. ASSESSMENT: 4D flow MRI covering the abdominal aorta and bilateral common iliac arteries and the corresponding stent-graft (SG) lumen was performed before and after EVAR. Plasma brain natriuretic peptide (BNP) was measured within 1 week before and 1 month after EVAR. The hemodynamic data, including mean velocity and the local EL, were compared pre-/post-EVAR. EL was correlated with AAA neck angle and with BNP. Patients were subdivided into deformed (N = 5) and undeformed SG subgroups (N = 8) and pre-/post-EVAR BNP compared in each. STATISTICS: Parametric or nonparametric methods. Spearman's rank correlation coefficients (r). The interobserver/intraobserver variabilities with Bland-Altman plots. A P value < 0.05 is considered significant. RESULTS: The mean velocity (cm/sec) at the AAA was five times greater after EVAR: 4.79 ± 0.32 vs. 0.91 ± 0.02. The total EL (mW) increased by 1.7 times after EVAR: 0.487 (0.420, 0.706) vs. 0.292 (0.192, 0.420). The total EL was proportional to the AAA neck angle pre-EVAR (r = 0.691) and post-EVAR (r = 0.718). BNP (pg/mL) was proportional to the total EL post-EVAR (r = 0.773). In the deformed SG group, EL (0.349 [0.261, 0.416]) increased 2.4-fold to 0.848 (0.597, 1.13), and the BNP 90.3 (53.6, 105) to 100 (67.2, 123) post-EVAR. CONCLUSION: The local EL showed a 1.7-fold increase after EVAR. The larger increase in the EL in the deformed SG group might be a potential concern for frail patients. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.

Embolization using patient-specific vascular models created by a 3D printer for difficult cases: a report of two cases.

With the widespread use of three-dimensional printers, organ models created by these printers are now being used in the medical field for preoperative planning of surgeries. In this article, we report two cases in which embolization was expected to be difficult, and the three-dimensional printer-based vascular modeling was helpful in planning the surgery. The first case involved an aneurysm of the splenic artery. We attempted to embolize the aneurysm but were unable to advance the catheter into the distal artery and discontinued the procedure. The second case was a perianal varicose vein, which was initially treated with percutaneous transhepatic obliteration but was recanalized and required embolization. However, we expected difficulty in selecting the inferior mesenteric vein. In both cases, the vascular models were created using a 3D printer from the patients' computed tomography images. Preoperative planning, including treatment simulation, was based on these models. The time required to print a three-dimensional vascular model was approximately 12 hours at a cost of less than $10 each. Patient-specific vascular models using a three-dimensional printer can be a simple and inexpensive tool that can increase the success of embolization in difficult cases.

A case of stent-graft implantation for postpancreaticoduodenectomy hemorrhage in a patient with a reconstructed gastric tube.

In patients with a reconstructed gastric tube, the right gastroepiploic artery is a very important feeding artery of the tube, which must be preserved when performing a pancreaticoduodenectomy. A 76-year-old man with a reconstructed gastric tube underwent pancreaticoduodenectomy for distal bile duct carcinoma. On postoperative day 8, he had an arterial hemorrhage from a drain, apparently from a ligation of the anterior superior duodenal artery. He, therefore, underwent stent-graft placement in the gastroduodenal artery. The stent-grafts were temporarily occluded, and the gastric tube was necrotizing. However, thrombolytic therapy allowed the stent-grafts to reopen and prevented gastric tube necrosis. We believe our case of stent-graft implantation in the gastroduodenal artery is the first of this kind to successfully prevent lethal necrosis of the gastric tube.

Evaluation of segment 4 portal vein embolization added to right portal vein for right hepatic trisectionectomy: A retrospective propensity score-matched study.

BACKGROUND: Adding segment 4 (S4) portal vein embolization (PVE) to right PVE before right hepatic trisectionectomy is controversial. We retrospectively examined the effect of S4 PVE on segments 2 and 3 (S2 + 3) hypertrophy. METHODS: We reviewed patients with biliary carcinoma who underwent right PVE with (R3PVE) or without (R2PVE) S4 PVE using gelatin sponge particles and coils (2010-2019). Propensity score matching balanced the cohort for baseline characteristics, including total liver volume and S2 + 3 volume before PVE. We compared the groups regarding the S2 + 3 volume changes after PVE. RESULTS: Of 178 enrolled patients, 38 underwent R3PVE for right hepatic trisectionectomy and 140 underwent R2PVE for right hepatectomy. Twenty-eight patients from each group were respectively matched. The median absolute volume increase in (146 cm3 vs 70 cm3 ), hypertrophy rate of (52.4% vs 32.3%), and kinetic growth rate of (3.1%/wk vs 2.0%/wk) S2 + 3 were significantly higher in the R3PVE group than in the R2PVE group. In the pre-matched cohort, the rate of posthepatectomy liver failure and postoperative hospital stay did not significantly differ between the patients who underwent right hepatic trisectionectomy and right hepatectomy. CONCLUSION: R3PVE increased the S2 + 3 volume more effectively than R2PVE in patients with biliary carcinoma.

Successful treatment of esophageal bleeding due to rupture of major aortopulmonary collateral arteries by transcatheter arterial embolization.

Major aortopulmonary collateral arteries (MAPCAs) are unique vessels associated with hypoxia induced by congenital heart disease (CHD). Although MAPCAs are essential to supply blood to the lungs, their development and proliferation can induce life-threatening complications, such as rupture into the lung. Here, we describe a rare case of esophageal bleeding from MAPCAs in a CHD patient, which was successfully treated by transcatheter arterial embolization (TAE). A 16-year-old male with CHD experienced a hematemesis and melena after the Bentall procedure to treat valvular heart disease. Emergent esophagogastroduodenoscopy revealed spurting bleeding from the middle esophageal vessels; accordingly, endoscopic variceal ligation (EVL) was performed. However, he had a hematemesis again after 2 weeks of EVL. The arterial phase of dynamic computed tomography indicated that a MAPCA associated with CHD was the origin of bleeding. Hence, TAE of this MAPCA with a mixture of n-butyl-2-cyanoacrylate and ethiodized oil was performed to prevent re-bleeding. Color Doppler mode in endoscopic ultrasonography via the esophagus revealed mosaic-like signals in MAPCAs located in the esophageal wall. This finding was consistent with tortuous MAPCAs accompanied by turbulent blood flow. When clinicians encounter CHD patients with unexpected massive esophageal bleeding, bleeding related to MAPCAs should be considered.

Efficacy of percutaneous transhepatic portal vein embolization using gelatin sponge particles and metal coils.

BACKGROUND: Percutaneous transhepatic portal vein embolization (PTPE) can increase the future liver remnant (FLR) volume before extended liver resection; however, there is no current consensus regarding the best embolic material for PTPE. PURPOSE: To evaluate the efficacy of PTPE using gelatin sponge particles and coils. MATERIAL AND METHODS: The medical records of 136 patients who underwent PTPE using gelatin sponge particles and metal coils were retrospectively reviewed. We evaluated the procedural details, liver volume on CT, and clinical status before and after PTPE. RESULTS: The mean FLR volume increased significantly from 390 ± 147 cm3 to 508 ± 141 cm3 (P < 0.001). A mean of 22.1 ± 9.4 days after PTPE, the mean increase in the ratio of FLR volume to total liver volume was 9.4 ± 6.5%. Complications related to PTPE occurred in five patients, including arterial damage (n = 4) and biloma (n = 1). The white blood cell count and C-reactive protein level increased significantly and then returned to baseline within seven days. Aspartate aminotransferase and alanine aminotransferase showed no significant changes. Fever (defined by the Common Terminology Criteria for Adverse Events v4.0) was reported in 74 patients (54%), but it was generally mild (Grade 1/2; n = 72). None of the patients experienced severe complications that required cancellation of surgery. CONCLUSION: PTPE with gelatin sponge particles and coils may impose low physical stress on patients and is a safe method of inducing a significant increase of FLR.

Diagnostic value of SPIO-mediated breath-hold, black-blood, fluid-attenuated, inversion recovery (BH-BB-FLAIR) imaging in patients with hepatocellular carcinomas.

PURPOSE: We assessed the value of adding a breath-hold, black-blood, fluid-attenuated, inversion recovery (BH-BB-FLAIR) sequence with a small motion-probing gradient (b=10 s/mm(2)) using superparamagnetic iron oxide (SPIO) to our present studies that utilize SPIO to detect hepatocellular carcinoma (HCC). We used inversion recovery (IR) in a FLAIR sequence to suppress signals from cysts and a low b-value to suppress vessel signals and provide higher signal to noise than that using high b-value diffusion-weighted imaging. Use of SPIO is expected to reduce the signal in both normal liver parenchyma and in most benign lesions. MATERIALS AND METHODS: In 19 patients, we reviewed 38 HCC nodules diagnosed by CT arterioportography (CTAP) and CT during hepatic arteriography (CTHA). We divided SPIO-mediated images into sets, those obtained with and without BH-BB-FLAIR. Six radiologists individually interpreted the 2 image sets and sorted them by their confidence levels for the presence of HCC, and we calculated the area under the receiver operating characteristic (ROC) curve (Az) for each image set. RESULTS: On images obtained with BH-BB-FLAIR after SPIO administration, 33 of the 38 HCC nodules appeared as areas of high signal and cyst signal was extinguished. The ROC analysis showed significantly higher Az values in the set with BH-BB-FLAIR (0.89) than in the set without (0.83). CONCLUSIONS: Adding BH-BB-FLAIR to existing SPIO-mediated imaging protocols improved detection of HCC nodules and added only 24 s to the scan time.

Stent-graft treatment for bleeding superior mesenteric artery pseudoaneurysm after pancreaticoduodenectomy.

We report two cases of intraperitoneal bleeding from superior mesenteric artery (SMA) pseudoaneurysm after pancreaticoduodenectomy for pancreatic head carcinoma. In both cases, a stent-graft was deployed on the main SMA to exclude pseudoaneurysm and to preserve blood flow to the bowel. Bleeding stopped after the procedure. One patient was able to be discharged but died from carcinoma recurrence 4 months later. The other patient died of sepsis and stent-graft infection 5 months later. These patients remained free of intraperitoneal rebleeding during the follow-up period.

Contrast-enhanced MR imaging of metastatic brain tumor at 3 tesla: utility of T(1)-weighted SPACE compared with 2D spin echo and 3D gradient echo sequence.

We evaluated the newly developed whole-brain, isotropic, 3-dimensional turbo spin-echo imaging with variable flip angle echo train (SPACE) for contrast-enhanced T(1)-weighted imaging in detecting brain metastases at 3 tesla (T). Twenty-two patients with suspected brain metastases underwent postcontrast study with SPACE, magnetization-prepared rapid gradient-echo (MP-RAGE), and 2-dimensional T(1)-weighted spin echo (2D-SE) imaging at 3T. We quantitatively compared SPACE, MP-RAGE, and 2D-SE images by using signal-to-noise ratios (SNRs) for gray matter (GM) and white matter (WM) and contrast-to-noise ratios (CNRs) for GM-to-WM, lesion-to-GM, and lesion-to-WM. Two blinded radiologists evaluated the detection of brain metastases by segment-by-segment analysis and continuously-distributed test. The CNR between GM and WM was significantly higher on MP-RAGE images than on SPACE images (P<0.01). The CNRs for lesion-to-GM and lesion-to-WM were significantly higher on SPACE images than on MP-RAGE images (P<0.01). There was no significant difference in each sequence in detection of brain metastases by segment-by-segment analysis and the continuously-distributed test. However, in some cases, the lesions were easier to detect in SPACE images than in other sequences, and also the vascular signals, which sometimes mimic lesions in MP-RAGE and 2D-SE images, were suppressed in SPACE images. In detection of brain metastases at 3T magnetic resonance (MR) imaging, SPACE imaging may provide an effective, alternative approach to MP-RAGE imaging for 3D T(1)-weighted imaging.

Endovascular management of ruptured pancreaticoduodenal artery aneurysms associated with celiac axis stenosis.

The purpose of this study was to assess the efficacy of transcatheter arterial embolization for ruptured pancreaticoduodenal artery (PDA) aneurysms associated with celiac axis stenosis (CS). Seven patients (four men and three women; mean age, 64; range, 43-84) were treated with transcatheter arterial embolization between 2002 and 2007. They were analyzed with regard to the clinical presentation, radiological finding, procedure, and outcome. All patients presented with sudden epigastric pain or abdominal discomfort. Contrast-enhanced CT showed a small aneurysm and retroperitoneal hematoma around the pancreatic head in all patients. The aneurysms ranged from 0.3 to 0.9 cm in size. In one patient, two aneurysms were detected. The aneurysms were located in the pancreaticoduodenal artery (n = 5) and the dorsal pancreatic artery (n = 3). Embolization was performed with microcoils in all aneurysms (n = 8). N-Butyl 2-cyanoacrylate (n = 1) and gelatine particle (n = 1) were also used. Complete occlusion was achieved in four patients. In the other three patients, a significantly reduced flow to the aneurysm remained at final angiography. However, these aneurysms were thrombosed on follow-up CT within 2 weeks. And there was no recurrence of the symptoms and bleeding during follow-up (mean, 28 months; range, 5-65 months) in all patients. In conclusion, transcatheter arterial embolization for PDA aneurysms associated with CS is effective. Significant reduction of the flow to the aneurysm at final angiography may be predictive of future thrombosis.