Hiroki Sanda

Preoperative microcoil embolization of the common hepatic artery for pancreatic body cancer

AIM To evaluate safety and feasibility of microcoil embolization of the common hepatic artery under proper or distal balloon inflation in preoperative preparation for en bloc celiac axis resection for pancreatic body cancer. METHODS Fifteen patients (11 males, 4 females; median age, 67 years) with pancreatic body cancer involving the nerve plexus surrounding the celiac artery underwent microcoil embolization. To alter the total hepatic blood flow from superior mesenteric artery (SMA), microcoil embolization of the common hepatic artery (CHA) was conducted in 2 cases under balloon inflation at the proximal end of the CHA and in 13 cases under distal microballoon inflation at the distal end of the CHA. RESULTS Of the first two cases of microcoil embolization with proximal balloon inflation, the first was successful, but there was microcoil migration to the proper hepatic artery in the second. The migrated microcoil was withdrawn to the CHA by an inflated microballoon catheter. Microcoil embolization was successful in the other 13 cases with distal microballoon inflation, with no microcoil migration. Compact microcoil embolization under distal microballoon inflation created sufficient resistance against the vascular wall to prevent migration. Distal balloon inflation achieved the requisite 1 cm patency at the CHA end for vascular clamping. All patients underwent en bloc celiac axis resection without arterial reconstruction or liver ischemia. CONCLUSION To impede microcoil migration to the proper hepatic artery during CHA microcoil embolization, distal microballoon inflation is preferable to proximal balloon inflation.

N-butyl cyanoacrylate embolization with blood flow control of an arterioportal shunt that developed after radiofrequency ablation of hepatocellular carcinoma.

We present a case of a patient with rapid deterioration of esophageal varices caused by portal hypertension accompanied by a large arterioportal shunt that developed after radiofrequency ablation of hepatocellular carcinoma. We used n-butyl cyanoacrylate (NBCA) as an embolic material to achieve pinpoint embolization of the shunt, because the microcatheter tip was 2 cm away from the shunt site. Under hepatic arterial flow control using a balloon catheter, the arterioportal shunt was successfully embolized with NBCA, which caused an improvement in the esophageal varices.

Basic Study of a Mixture of N-butyl Cyanoacrylate, Ethanol, and Lipiodol as a New Embolic Material

PURPOSE To clarify the configuration change of N-butyl cyanoacrylate (NBCA) polymerization with increasing proportion of ethanol, the properties of a mixture of NBCA with lipiodol plus ethanol (NLE), and the feasibility of use of NLE for aneurysm packing in a swine model. MATERIALS AND METHODS The polymerization configuration of NLE was explored using ratios of 1-4 parts NBCA and 1-3 parts ethanol per 1 part of lipiodol; a 1:1 ratio of NBCA to lipiodol (NLE110) was used as a control. The distance that NLE migrated into saline flowing in a tube was measured. A carotid artery aneurysm was created in each of 18 swine. Aneurysmal packing with three configurations--NLE110, NLE at a ratio of 1:1:2 (NLE112), and NLE at a ratio of 1:1:3 (NLE113)--was attempted in six swine for each configuration. RESULTS Regardless of NBCA composition, medium-sized droplets, a single large droplet, and a noodle-shaped extrusion were observed in NLE with lipiodol versus ethanol ratios of 1:1, 1:2, and 1:3. NLE110 migrated as viscous fluid to 190 cm from the injection site, whereas NLE112 migrated for 81 cm ± 11 and NLE113 migrated for 74 cm ± 9. Instant outflow of NLE110 from the six aneurysms caused occlusion of the parent artery, with adhesion to the microcatheter. Packing was achieved with minimal adhesion for all six of the aneurysms packed with NLE112 or with NLE113. CONCLUSIONS With high ratios of ethanol, the NLE polymerization configuration acquired solid-like properties with potent occlusive ability and negligible adhesion to the microcatheter, suggesting its feasibility for packing of aneurysms.

Differentiation of pancreatic serous cystadenoma from endocrine tumor and intraductal papillary mucinous neoplasm based on washout pattern on multiphase CT.

Objective To evaluate the washout (WO) pattern of serous cystadenomas (SCAs) compared with endocrine tumors (ETs) and intraductal papillary mucinous neoplasm (IPMN). Methods Patients with serous cystadenoma (n = 12), ET (n = 29), and IPMN (n = 35) underwent 4-phase computed tomography CT. Tumors were categorized as hyperdense or hypodense. Computed tomographic values measured were unenhanced attenuation (AU), pancreatic attenuation (A12, 12 seconds), portal attenuation (A35), and equilibrium (A158). Computed tomographic parameters calculated were wash-in (WI) = A12 − AU; WO = A12 − A35; and washout ratio (WOR) = WO/WI × 100/22. Results Hyperdense SCAs had significantly higher WOR than did hyperdense ETs (P = 0.001). Among the 3 hypodense tumors, SCAs had the significantly highest WOR (P < 0.05/3). Relative to the pancreas, the WOR of SCAs were equivalent, whereas the WOR of ETs and IPMNs were significantly lower. Conclusions Hyperdense SCAs had significantly higher WOR than did hyperdense ETs, and hypodense SCAs had the significantly highest WOR among the three.

Endovascular Stenting and Stent-graft Repair of a Hemorrhagic Superior Mesenteric Artery Pseudoaneurysm and Dissection Associated with Pancreaticoduodenectomy

This report presents a 73-year-old woman with intraperitoneal bleeding from a superior mesenteric artery (SMA) pseudoaneurysm and dissection after pancreaticoduodenectomy (PD). A self-expanding bare metal stent was placed in the distal SMA across the area of dissection, and a stent-graft was subsequently placed across the pseudoaneurysm emerging from the proximal site by overlapping the bare stent, resulting in complete exclusion of the pseudoaneurysm and control of the dissection. Bleeding was controlled after the endovascular procedure. The combination of endovascular stenting and stent-graft repair is feasible and useful in comorbid cases of SMA pseudoaneurysm and dissection.

Three benefits of microcatheters for retrograde transvenous obliteration of gastric varices

AIM To evaluate the usefulness of the microcatheter techniques in balloon-occluded retrograde transvenous obliteration (BRTO) of gastric varices. METHODS Fifty-six patients with gastric varices underwent BRTOs using microcatheters. A balloon catheter was inserted into gastrorenal or gastrocaval shunts. A microcatheter was navigated close to the varices, and sclerosant was injected into the varices through the microcatheter during balloon occlusion. The next morning, thrombosis of the varices was evaluated by contrast enhanced computed tomography (CE-CT). In patients with incomplete thrombosis of the varices, a second BRTO was performed the following day. Patients were followed up with CE-CT and endoscopy. RESULTS In all 56 patients, sclerosant was selectively injected through the microcatheter close to the varices. In 9 patients, microcoil embolization of collateral veins was performed using a microcatheter. In 12 patients with incomplete thrombosis of the varices, additional injection of sclerosant was performed through the microcatheter that remained inserted overnight. Complete thrombosis of the varices was achieved in 51 of 56 patients, and the remaining 5 patients showed incomplete thrombosis of the varices. No recurrence of the varices was found in the successful 51 patients after a median follow up time of 10.5 mo. We experienced one case of liver necrosis, and the other complications were transient. CONCLUSION The microcatheter techniques are very effective methods for achieving a higher success rate of BRTO procedures.

Inferior pancreaticoduodenal artery aneurysm treated with coil packing and stent placement.

Two cases with a pancreaticoduodenal arterial aneurysm accompanied with superior mesenteric artery (SMA) stenosis were previously described and both were treated surgically. However, for interventional treatment, securing a sufficient blood supply to the SMA should be a priority of treatment. We present the case of a 71-year-old male with a 20 mm diameter pancreaticoduodenal arterial aneurysm accompanied by SMA stenosis at its origin. The guidewire traverse from SMA to the aneurysm was difficult because of the tight SMA stenosis; however, the guidewire traverse from the celiac artery was finally successful and was followed by balloon angioplasty using a pull-through technique, leading to stent placement. Thereafter, coil packing through the SMA achieved eradication of the aneurysm without bowel ischemia. At the last follow-up computed tomography 8 mo later, no recurrence of the aneurysm was confirmed. The pull-through technique was useful for angioplasty for tight SMA stenosis in this case.

Successful Treatment of Endoscopically Unmanageable Rectal Varices by Balloon-occluded Antegrade Transvenous Sclerotherapy Followed by Microcoil Embolization

The present report describes two cases of endoscopically unmanageable rectal varices that were treated by balloon-occluded antegrade transvenous sclerotherapy (BATS) followed by microcoil embolization. Follow-up endoscopy confirmed eradication of the rectal varices. Balloon-occluded rectal venography showed stasis of contrast material and sclerosing agent for 30 minutes in both cases of rectal varices, which indicated that the inflow vessel was a single dilated superior rectal vein without other minor inflow vessels. BATS appears to be a feasible therapeutic option for the treatment of rectal varices of this hemodynamic type.

Clinical evaluation of transcatheter arterial chemoembolization with 2-day-soluble gelatin sponge particles for hepatocellular carcinoma-comparison with insoluble gelatin sponge particles.

PURPOSE To compare therapeutic effect, adverse events, and embolized hepatic artery impairment in transcatheter arterial chemoembolization between Lipiodol plus insoluble gelatin sponge particles (Gelpart) and Lipiodol plus 2-day-soluble gelatin sponge particles (2DS-GSPs). MATERIALS AND METHODS In a single-center, prospective, randomized controlled trial, patients with hepatocellular carcinoma were assigned to the 2DS-GSP group or the Gelpart group. Radiographic response at 3 months per modified Response Evaluation Criteria In Solid Tumors was evaluated as the primary endpoint; secondary endpoints were safety (per Common Terminology Criteria for Adverse Events, version 4.0) within 3 months and hepatic branch artery impairment at the time of repeat chemoembolization (grade 0, no damage; grade I, mild vessel wall irregularity; grade II, overt stenosis; grade III, occlusion of more peripheral branch artery than subsegmental artery; grade IV, occlusion of subsegmental artery). Grade II, III, or IV indicated significant hepatic artery impairment. RESULTS Thirty-seven patients with 143 nodules were randomized to the 2DS-GSP group and 36 patients with 137 nodules were randomized to the Gelpart group. No significant differences in patient background existed between groups. Target lesion response and overall tumor response in the 2DS-GSP and Gelpart groups were 77.7% versus 76.9% and 78.3% versus 77.8%, respectively, with no significant differences. No significant difference in adverse events existed between groups. Hepatic artery impairment was observed in 5% of patients in the 2DS-GSP group (n = 32) and in 16% in the Gelpart group (n = 33; P< .001). CONCLUSIONS Transcatheter arterial chemoembolization with 2DS-GSPs resulted in the same therapeutic and adverse effects as chemoembolization with Gelpart while causing significantly less hepatic artery impairment.

Evaluation of vascular puncture needles with specific modifications for enhanced ultrasound visibility: In vitro study

AIM To determine which modification to a vascular puncture needle results in increased visualization during ultrasound (US)-guided vascular puncture. METHODS We evaluated US images of a phantom made of degassed gelatin and each of the following four modified versions of a commercially available vascular puncture needle (18 G): re-cut needle, dimple needle, rough-surface needle (rough over the sections of needle located 3-6 mm from the tip), and a needle with four side holes (side holes covered by the sheath). An unmodified commercially available puncture needle was used as a control. Five interventional radiologists evaluated image quality according to the following classification grade: I, invisible; II, poor; III, moderate; IV, good; V, excellent. RESULTS The highest score for needle visualization was obtained for the needle with four side holes. The re-cut needle scored the same as the control. Multiple comparisons were conducted using overall evaluation scores among the commercially available needle, dimple needle, rough-surface needle (3-6 mm), and the needle with four side holes. A significantly higher score was obtained for the needle with four side holes (P < 0.05/6). CONCLUSION The needle with four side holes was prominently visualized and gained a significantly higher score (compared with the other needles) in a phantom evaluation.