In Vitro Characterization of Drug-Loaded Superabsorbent Polymer Microspheres: Absorption and Release Capacity of Contrast Material, Antibiotics and Analgesics.

PURPOSE: To examine the characteristics of drug-loaded superabsorbent polymer microspheres (SAP-MS) such as drug absorption, drug release, diameter, and visibility. MATERIALS AND METHODS: SAP-MS (HepaSphere150-200 µm; Merit Medical, South Jordan, UT, USA) were suspended in drug solutions: (a) cefazolin, (b) lidocaine, (c) iopamidol and cefazolin, (d) iopamidol and lidocaine, and (e) iopamidol, cefazolin, and lidocaine. The concentrations of drugs were measured, and the amount of each drug absorbed was calculated. Filtered drug-loaded SAP-MS were mixed with saline, and the drug release rates were calculated. The diameter changes of SAP-MS during absorption were observed. Radiography of drug-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio (CNR). RESULTS: The drug concentration did not change during absorption. The release rates increased for 10 min and then came to an equilibrium. The mean amounts of drug absorbed at 180 min and mean release rates at 24 h were (a) cefazolin: 265.4 mg, 64.2%; (b) lidocaine: 19.6 mg, 75.6%; (c) iopamidol: 830.2 mg, 22.5%; cefazolin: 137.6 mg, 21.2%; (d) iopamidol: 1620.6 mg, 78.5%; lidocaine: 13.5 mg, 81.4%; and (e) iopamidol: 643.7 mg, 52.9%; cefazolin: 194.0 mg, 51.6%; lidocaine: 5.3 mg, 58.4%. The diameter of SAP-MS increased for approximately 15 min. Finally, the diameters of SAP-MS were (a) 3.9 times, (b) 5.0 times, (c) 2.2 times, (d) 5.5 times, and (e) 3.6 times larger than the original size. Drug-loaded SAP-MS containing iopamidol were visible under X-ray imaging, with CNRs of (c) 3.0, (d) 9.0, and (e) 4.5. CONCLUSION: SAP-MS can absorb and release iopamidol, cefazolin, and lidocaine.

Usefulness of peripherally inserted central catheter port system (PICC-PORT) implantation in the sitting position: a new technique for cases unsuitable for conventional implantation.

PURPOSE: Totally implantable central venous access port implantation is typically performed in the supine position. However, some patients cannot adopt the supine position due to severe pain and/or dyspnea. The present study evaluated the technical feasibility of peripherally inserted central catheter port system (PICC-PORT) implantation in the sitting position in such cases. MATERIALS AND METHODS: In the sitting position method, PICC-PORT implantation was performed with the patients seated on a videofluoroscopy chair positioned between the limbs of an angiographic C-arm and the operative upper arm positioned on an arm stand. From January 2019 to September 2021, eight patients underwent PICC-PORT implantations using this sitting method. We also evaluated 251 consecutive patients with conventional supine position PICC-PORT implantation as controls. Differences in technical success, procedure time and complications were retrospectively assessed between the two groups. RESULTS: Procedural success rates were 100% in both groups. Median procedure times in the sitting and conventional groups were 42 and 44 min, respectively. No complications were observed in the sitting group. There were no significant differences between the two groups in procedure time (p = 0.674) and complications (p = 1.000). CONCLUSION: Implantation of PICC-PORT in the sitting position is technically feasible and useful.

Stent graft treatment for coronary sinus hemorrhage associated with esophageal cancer.

Hemorrhage arising from the coronary sinus is very rare and can be lethal. It has historically been treated surgically. The present patient had coronary sinus rupture secondary to esophageal cancer and an abscess in the pericardium. Due to her poor general status, this patient was contraindicated for surgery and underwent endovascular therapy. The hemorrhage was treated by stent graft deployment and the patient was temporarily discharged. Two months later, CT showed that the stent graft was occluded by thrombosis. The patient died without hemorrhage 2.5 months thereafter.

Distribution of scatter radiation by C-arm cone-beam computed tomography in angiographic suite: measurement of doses and effectiveness of protection devices.

Distribution of radiation by C-arm cone-beam computed tomography (CBCT) in the angiographic suite and effectiveness of protection devices were assessed. CBCT image of a human phantom was obtained by a rotation of 220 degrees during 8 seconds of exposure. One hundred and twelve dosimeters were placed at different positions around the beam entry site, and color maps of dose distributions were drawn for horizontal and vertical planes. The measurements showed the highest radiation dose over 600 µGy by a single CBCT image acquisition at a distance of 60 cm from the beam entry site and a height of 90 cm from the floor. The color maps demonstrated the dose distribution to be more intense at the bilateral directions of the phantom. With the use of a ceiling-mounted transparent lead-acryl screen and a table-suspended lead curtain, the doses were reduced by 45-92 % at a direction of 210 degrees and a distance of 120 cm.

Endometrial cancer arising from adenomyosis: Case report and literature review of MRI findings.

Endometrial cancer arising from adenomyosis (EC-AIA) is extremely rare, and the typical magnetic resonance imaging (MRI) findings of EC-AIA have not been established. We report a case of EC-AIA that was detected preoperatively on MRI and conduct a literature review of the MRI findings of EC-AIA.

Percutaneous Retrieval of a Misinserted Pigtail Catheter Straightener during Infra-Renal Abdominal Aortic Stenting: A Case Report.

Percutaneous retrieval of an intravascular foreign body is a minimally invasive technique. Using cone-beam computed tomography and the lateral grasp technique, we successfully retrieved a pigtail catheter straightener that had been misinserted into the right common iliac artery. Some examples of catheter straightener retrieval have been reported; however, it is important to take care not to accidentally insert a catheter straightener into a vessel via an angiographic sheath.

In vitro evaluation of radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) with static imaging and flow model.

PURPOSE: To evaluate the radiopacity of contrast-loaded superabsorbent polymer microspheres (SAP-MS) under X-ray imaging. MATERIALS AND METHODS: SAP-MS were suspended in contrast material (iodixanol) and the diameter change was assessed. The diameter of contrast-loaded SAP-MS in saline was measured sequentially. Radiography of the contrast-loaded SAP-MS was evaluated as radiopacity by contrast-to-noise ratio and visibility by multiple reader scoring. Under digital subtraction angiography, contrast-loaded SAP-MS were injected into a flow model. The flow speed was 1-10 cm/s, and images were acquired at 1-7.5 frames per second using a pulse width of 10-85 ms. Images were assessed by multiple reader scoring. RESULTS: The diameter of SAP-MS increased to 4.0-5.0 times its original size for approximately 15 min. The diameter of contrast-loaded SAP-MS in saline further increased by 10-30% within several minutes and returned to the previous size. Radiopacity and visibility of contrast-loaded SAP-MS decreased in 30 min after mixing with saline. Visibility was better with slow flow speed and narrow pulse width. CONCLUSION: For effective observation, contrast-loaded SAP-MS should be kept in non-diluted contrast material until use. The conditions of slower flow and use of a narrow pulse width are recommended.

Polidocanol Sclerotherapy Combined with Transarterial Embolization Using n-Butyl Cyanoacrylate for Extracranial Arteriovenous Malformations.

PURPOSE: To assess the safety and effectiveness of polidocanol sclerotherapy combined with transarterial embolization using a liquid adhesive agent (n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs). MATERIALS AND METHODS: Twenty-three patients with symptomatic AVMs in the head and neck (6), upper (7) and lower extremity (10) with a mean age of 42 years (range 4-74) treated with polidocanol sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 2 type I, 6 type II, 6 type IIIa and 9 type IIIb. Arterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. Polidocanol mixed with contrast material or carbon dioxide was delivered by percutaneous direct puncture. RESULTS: Treatment was successfully performed in all patients. In the mean follow-up period of 38 months, symptoms resolved or improved in 20/23 patients (87.0%). AVMs were devascularized 100% in 2 patients, 76-99% in 13, 50-75% in 7 and < 50% in 1. More than 50% devascularization was seen in 22 patients (95.6%). Two (8%) patients had complete remission, 17 (74%) had partial remission and 3 (13%) had no remission. There was no aggravation. Treatment was considered effective (complete and partial remission) in 20 patients (87.0%). Minor complications including localized arterial thrombosis (2) and spontaneously healing skin ulcer (1) were seen in 2 patients (8.7%). There were no major procedure-related complications. CONCLUSION: Polidocanol sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications.

Renal dysfunction after abdominal or thoracic endovascular aortic aneurysm repair: incidence and risk factors.

PURPOSE: To determine the incidence and risk factors of renal dysfunction after abdominal endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR). MATERIALS AND METHODS: The study consisted of 227 patients treated with EVAR and 90 with TEVAR for aortic aneurysms. Parameters, including patients' background factors, preoperative renal function, contrast dose and aortic wall irregularity on CT images were assessed in relation to postoperative renal dysfunction. RESULTS: Deterioration of renal function was observed in 33 of 218 patients (15.1%) after EVAR and in 7 of 79 (8.9%) patients after TEVAR. Hemodialysis was required in one patient after EVAR. In EVAR, renal dysfunction correlated with age (p = 0.034) and occlusion of accessory renal artery (p = 0.0001). In TEVAR, renal dysfunction correlated with age (p = 0.021), contrast dose (p = 0.042) and irregularity of the descending aortic wall (p = 0.023). In a multiple regression analysis, postoperative renal dysfunction was correlated with occlusion of accessory renal artery (p = 0.0003) after EVAR, and age (p = 0.02), contrast dose (p = 0.026) and irregularity of the descending aortic wall (p = 0.042) after TEVAR. CONCLUSION: Occlusion of accessory renal artery in EVAR, and age, contrast dose and irregularity of the descending aortic wall in TEVAR were considered to be predictors of postoperative renal dysfunction.

Uterine artery embolization by use of porous gelatin particles for symptomatic uterine leiomyomas: comparison with hand-cut gelatin sponge particles.

PURPOSE: To evaluate the results of uterine artery embolization (UAE) for symptomatic uterine leiomyoma by use of porous gelatin particles (PGP) in comparison with conventional hand-cut gelatin sponge particles. MATERIALS AND METHODS: One hundred and fifteen consecutive patients who had undergone UAE were retrospectively assessed. The first 64 patients were treated with hand-cut gelatin sponge and the last 51 with PGP. Extent of infarction, volume reduction of the dominant leiomyoma on magnetic resonance (MR) imaging, and change in symptoms were assessed. RESULTS: UAE was successfully performed for all patients. No major complications were observed. MR images one month after UAE showed that the mean extent of infarction of the dominant leiomyoma was 97 % for patients treated with PGP and 96 % for those treated with hand-cut gelatin sponge. Volume reductions of the dominant leiomyoma after 3, 6, 12, and 24 months were, respectively, 45, 56, 62, and 66 % for use of PGP and 45, 57, 63, and 68 % for use of hand-cut gelatin sponge. Symptoms including heavy menstrual bleeding, heavy menstrual pain, and abdominal heaviness had improved by 95-100 % at 12 months. There was no difference between the two groups. CONCLUSION: UAE with PGP is safe, and as effective as conventional gelatin sponge particles.

Ethanolamine oleate sclerotherapy combined with transarterial embolization using n-butyl cyanoacrylate for extracranial arteriovenous malformations.

PURPOSE: This study was designed to assess the safety and effectiveness of ethanolamine oleate (EO) sclerotherapy combined with transarterial embolization using a liquid adhesive agent (n-butyl cyanoacrylate, NBCA) for treatment of extracranial arteriovenous malformations (AVMs). METHODS: Twenty-four patients with symptomatic AVMs in the head and neck (n = 15), extremity (n = 5), and trunk (n = 4) with a mean age of 44 years (range, 18-78) treated with EO sclerotherapy were retrospectively assessed. AVMs were classified according to the angiographic morphology of the nidus. There were 7 type II (arteriolovenous fistulae), 6 type IIIa (arteriolovenulous fistulae with nondilated fistula), and 11 type IIIb (arteriolovenulous fistulae with dilated fistula). Transarterial embolization using NBCA was performed to reduce arterial flow before sclerotherapy. EO mixed with contrast material was delivered by percutaneous direct puncture or by catheterization into the draining vein under balloon occlusion. RESULTS: Three (13%) of 24 patients were cured, 17 (71%) had partial remission, and 4 (16%) no remission. Treatment was considered effective (cure and partial remission) in 20 patients (83%). Four patients (16%) experienced transient minor complications, including self-healing skin ulcer (n = 3) and localized deep venous thrombosis (n = 1). There were no major complications. CONCLUSIONS: EO sclerotherapy combined with transarterial embolization using NBCA is safe and effective for treating extracranial AVMs with an acceptable risk of minor complications.

Oblique approach for CT-guided liver radiofrequency ablation using multiplanar reformation images in hepatocellular carcinoma.

PURPOSE: To evaluate the feasibility and safety of CT-guided radiofrequency (RF) ablation by caudal-cranial oblique insertion using multiplanar reformation (MPR) images for hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: Twenty-two HCCs in 19 patients that were difficult to demonstrate on ultrasound (mean tumor diameter was 17.5 mm) were treated with CT-guided RF ablation by caudal-cranial oblique insertion to avoid pneumothorax, using MPR images after transcatheter arterial chemoembolization. The insertion point and direction of insertion, avoiding aerated lung parenchyma, bones, large vessels, and intestine, were sought on the MPR images. Technical success was defined as complete eradication of tumor enhancement in the contrast-enhanced CT. Local tumor progression was defined by the appearance of enhanced tumor adjacent to the zone of ablation. The technical success rate, local tumor progression, and complications were investigated. RESULTS: The coronal plane was used for insertion in 18 tumors, the sagittal plane in 3 tumors, and the oblique plane in 1 tumor. RF electrode placement was successful and complete necrosis was obtained in all cases. During the mean follow-up period of 38.0 months, local tumor progression was not detected in any of the patients. There were no major complications, including pneumothorax. CONCLUSION: CT-guided RF ablation by caudal-cranial oblique insertion using MPR images is a feasible and safe therapeutic option.

Three-dimensional CT angiography is useful for diagnosis of postabortion uterine hemorrhage: 3 case reports and review of the literature.

Uterine hemorrhage is a major complication associated with abortion. There are various causes of postabortion uterine hemorrhage. The objective of this article is to estimate the efficacy of three-dimensional computed tomography (3D-CT) angiography in the diagnosis of this condition. We present 3 case reports of women with massive genital bleeding after abortion. 3D-CT angiography clearly demonstrated the 3-D features of the feeding artery, the draining vein, and the surrounding normal structures. The diagnosis in patient 1 was a uterine arteriovenous malformation, in patient 2 was a placental polyp mimicking a uterine arteriovenous malformation, and in patient 3 was a placental polyp. Patients were all successfully treated with uterine artery embolization or transcervical resection of the placental polyp. We conclude that 3D-CT angiography is useful for making a differential diagnosis and for preoperative planning in patients with postabortion uterine hemorrhage.

Stenosis of the third portion of the duodenum due to bleeding from the anterior pancreaticoduodenal artery: assessment by multiphase contrast-enhanced examination with multislice CT.

BACKGROUND: This study was undertaken to analyze the CT findings for the rare pathological process that stenosis of the third portion of the duodenum was presumed to be caused by bleeding from the anterior pancreaticoduodenal artery. METHODS: Four consecutive patients presenting with frequent vomiting, who did not have well-known underlying disorders causing duodenal stenosis, were retrospectively recruited. Multiphase contrast-enhanced CT examinations were performed with 0.5- or 1-mm collimation. Two radiologists evaluated 2-mm axial and multiplanar reformatted images. RESULTS: In all patients, endoscopy demonstrated severe edematous stenosis of the third portion of the duodenum not associated with ulcer, bleeding, or neoplasm. The following CT findings were observed in all patients: homogenous swelling of the third portion of the duodenum associated with luminal stenosis in un-enhanced images, a band-like area of lower contrast-enhancement surrounding the walls of the third portion of the duodenum in pancreatic-phase images, and stenosis of the celiac axis. In three patients, aneurysms of the anterior pancreaticoduodenal artery in arterial-phase images were depicted. In the remaining patient, the diameter of the artery was irregular. CONCLUSIONS: Multiphase contrast-enhanced CT examination using a multislice CT scanner helps to establish the diagnosis of this pathological process.

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.

Arteriovenous malformation of the pancreas: assessment of clinical and multislice CT features.

BACKGROUND: This study was undertaken to analyze the clinical and CT features of arteriovenous malformation (AVM) of the pancreas. METHODS: Seven lesions in six consecutive patients (one woman and five men, mean age 51 years) with AVM of the pancreas who underwent multiphase contrast-enhanced CT with 0.5 or 1-mm collimation were retrospectively studied. CT images were evaluated and correlated with angiographic findings by two radiologists. RESULTS: In four patients, the lesions were incidental findings. Two patients presented with abdominal pain and gastrointestinal bleeding, respectively. Serum amylase levels were within normal limits in all patients. The mean size of the lesions was 32.1 mm (3.0-97.3 mm). Conglomeration of strong nodular stains and early enhancement of the portal venous system were observed for all the lesions. The diagnosis of AVM of the pancreas was retrospectively established for all lesions, but was prospectively established for four lesions. The feeding arteries of all lesions were depicted, showing agreement with those observed by angiography performed for four lesions. One lesion showed pseudocyst formation, haziness around the lesion, and strong enhancement of the duodenal wall. CONCLUSION: Multiphase CT examination using multislice CT is useful for diagnosis of AVM of the pancreas, including identification of the feeding arteries.

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.

Placenta previa increta/percreta in Japan: a retrospective study of ultrasound findings, management and clinical course.

AIM: Placenta accreta is an abnormally firm attachment of placental villi to the uterine wall, which may cause postpartum hemorrhage resulting in maternal morbidity and mortality. The purpose of the present study was to clarify the incidence, clinical background and prognosis of placenta previa increta/percreta treated with different modalities in Japan. METHODS: Medical records of cases with placenta previa increta/percreta in eight tertiary centers between January 1994 and December 2004 were reviewed. Placenta accreta without actual invasion into the myometrium confirmed by pathology was not included in placenta increta/percreta. Details of obstetric history, maternal background, ultrasonographical findings, the course of delivery, subsequent complications and management were noted. RESULTS: Among the total of 59,008 deliveries, 45,261 were by the vaginal route (76.7%) and 13 747 by cesarean section (23.3%). In this study, 408 cases were diagnosed as placenta previa (0.69%), 18 of these being placenta increta and 5 placenta percreta. Only 1.1% of cases of placenta previa without prior cesarean section were increta/percreta, in contrast to 37% of placenta previa after prior cesarean sections. Mean intraoperation blood loss was 3630 +/- 2216 g (increta) and 12,140 +/- 8343 g (percreta). One patient with placenta previa percreta died of hemorrhage. Stepwise treatment (cesarean section without separation of the placenta, arterial embolization and hysterectomy) was applied for 4 cases, which had the least blood loss. CONCLUSIONS: Placenta previa increta/percreta is a life-threatening disease. Patients who undergo hysterectomy after uterine arterial embolization demonstrate reduced intraoperation blood loss, and this treatment should be incorporated to reduce maternal morbidity.

CT depiction of small arteries in the pancreatic head: assessment using coronal reformatted images with 16-channel multislice CT.

BACKGROUND: To assess the capabilities of 16-channel multislice CT in acquiring almost exclusively arterial-phase images of the pancreas and depicting small pancreatic arteries in coronal reformatted images. MATERIALS AND METHODS: In 45 consecutive patients, arterial-phase contrast enhancement was measured in the aorta and its branches, portal venous system, and pancreas. Coronal reformatted images of 1.2- or 1.3-mm slice thickness at 0.8- or 0.9-mm intervals were generated from axial images acquired with 0.5-mm collimation. Two radiologists evaluated the quality of imaging in the arterial phase and the visibility of the pancreatic arteries in coronal reformatted images. RESULTS: Mean enhancement in the aorta and its branches was greater than 300 HU, while that in the portal venous system and pancreas was less than 100 HU. The images were judged to be suitable for delineating the pancreatic arteries in all patients. The following arteries were visualized: anterior superior pancreaticoduodenal (39 patients), posterior superior pancreaticoduodenal (41), anterior inferior pancreaticoduodenal (39), posterior inferior pancreaticoduodenal (33), dorsal pancreatic (42), its right branch (34), and transverse pancreatic (37). CONCLUSION: Multislice CT can depict small pancreatic arteries using coronal reformatted images generated from almost exclusively arterial-phase axial images acquired with 0.5-mm collimation.

Application of subsecond rotation scan to helical CT for lung cancer screening.

PURPOSE: To clarify whether the benefit of a reduced effective scan width obtained using a smaller pitch outweighs the disadvantage of increased noise in the application of a subsecond helical CT to mass screenings for lung cancer. MATERIALS AND METHODS: Twenty-two helical CT scans of the lung were obtained in 11 healthy subjects using the following parameters: 1) scan 1 was performed at 120 kVp, 50 mA, 10-mm collimation, 1-second/rotation, helical pitch of 2.0; and 2) scan 2 was performed at 120 kVp, 50 mA, 10-mm collimation, 0.75-second/rotation, helical pitch of 1.5. Computer-generated nodules measuring 10 mm and 6 mm in diameter showing ground-glass opacity were superimposed on these images. The detectability of each nodule was evaluated by six blinded readers using ROC analysis. RESULTS: Detectability of the 6-mm nodules was significantly higher in scan 2 than in scan 1. Detectability of the 10-mm nodules was not significantly different between scans 1 and 2. CONCLUSION: The use of a smaller pitch by employing a subsecond rotation scan in a helical CT for lung cancer screenings improves the detection of small lesions without increasing either the scanning time or radiation dose.