Selective Angiographic Evaluation in Patients with Simple-Type Pulmonary Arteriovenous Malformations Treated with Vascular Plug.

PURPOSE: To evaluate the angiographic recanalization rate of patients who underwent embolization juxta-proximal to the sac with AMPLATZER Vascular Plug type IV (AVP IV) for a simple pulmonary arteriovenous malformation (PAVM). MATERIAL AND METHODS: Ten patients (7 females and 3 males; median age, 47 years [range 28-83 years]) with 19 simple-type PAVMs who underwent embolization using an AVP IV between May 2015 and November 2021 were included in this retrospective study. The median feeding artery diameter on computed tomography was 4.0 mm (range 3-5.9 mm), and the median ratio of AVP IV size to feeding artery diameter on computed tomography was 1.5 (range 1.3-2.1). Technical success was defined by AVP IV placement at the junction between the pulmonary artery and the sac, or the pulmonary artery within 1 cm from the junction and beyond the last normal branch. The primary endpoint was the PAVM recanalization rate in selective or segmental pulmonary angiography performed 1 year post-embolization. RESULTS: The technical success rate of embolization juxta-proximal to the sac for simple-type PAVMs was 100%. None of the 19 lesions showed recanalization in pulmonary angiography performed 1 year after embolization. One patient experienced hemoptysis and pneumonia. CONCLUSION: Embolization of simple-type PAVMs' feeding vessel using AVP IV is safe and effective, with a high technical success rate and no recanalization on pulmonary angiography performed at 1 year post-embolization.

Two cases of tracheoinnominate artery fistula following tracheostomy treated successfully by endovascular embolization of the innominate artery.

Tracheoinnominate artery fistula (TIF) is a rare but lethal complication of tracheostomy. Treatment has traditionally been surgical, but advances in endovascular technology have led to a few recent reports of therapy with coils. We report 2 cases of TIF with massive hemorrhage that underwent successful treatment with endovascular occlusion. Endovascular repair is less invasive than open surgical repair and usually associated with a shorter recovery period. However, this technique may require multiple coils to inhibit blood flow into the fistula. This procedure should be considered one of the useful treatments for TIF.

A case of retained placenta increta successfully treated via uterine arterial embolization using N-butyl 2-cyanoacrylate.

A 29-year-old woman with placenta increta with hemorrhage underwent uterine artery embolization using 12.5% NBCA (N-butyl 2-cyanoacrylate) diluted with iodized oil (Lipiodol). Complete resolution of placenta increta without performing curettage was obtained. The uterus returned to its normal shape, with restored endometrium, junctional zone, and myometrium. Menstruation resumed after 3 months. In cases of retained placenta due to placenta accreta, and even those with placenta increta, uterine artery embolization using NBCA is a useful treatment.

Successful treatment of chylous ascites by superselective embolization of the inflowing lymphatic vessels using a steerable microcatheter: a case study.

Background: Chylous ascites resulting from postoperative lymphatic leaks are uncommon but difficult to treat in cases with unsuccessful conservative treatment. Case report: We report the case of an 80-year-old woman who had previously undergone multiple procedures for peritoneal dissemination 3.5 months after a laparoscopic bilateral salpingo-oophorectomy for ovarian cancer. After hospital discharge, she gradually gained weight, and examination findings indicated lymphatic leakage. We performed drainage using an 8.5-French Dawson-Mueller catheter, but more aggressive treatment was deemed necessary. We determined that it would be difficult to fill the large space, in which the leaking lymph fluid was accumulating, with embolic materials. Therefore, we performed superselective embolization of these inflowing lymphatic vessels to allow control of the chylous ascites. To overcome the technical difficulty associated with the insertion of a microcatheter from a large leakage cavity into a small inflow lymphatic vessel, we adopted a triple coaxial system that utilizes a steerable microcatheter. Successful embolization resulted in marked decrease in drainage. Follow-up computed tomography revealed no evidence of reaccumulation of chylous ascites. A three-month follow-up revealed no recurrence of lymphatic leakage. Conclusions: To our knowledge, this is the first report on the treatment of large retropenitoneal chylous leakage by superselective embolization of the inflowing lymphatic vessels using steerable microcatheters. This method allows large lymphatic leaks to be treated with only a small amount of N-butyl 2-cyanoacrylate mixture and without the use of coils, and we firmly believe that it should be considered for the treatment of large refractory chylous ascites.

Development and external validation of a deep learning-based computed tomography classification system for COVID-19.

BACKGROUND: We aimed to develop and externally validate a novel machine learning model that can classify CT image findings as positive or negative for SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR). METHODS: We used 2,928 images from a wide variety of case-control type data sources for the development and internal validation of the machine learning model. A total of 633 COVID-19 cases and 2,295 non-COVID-19 cases were included in the study. We randomly divided cases into training and tuning sets at a ratio of 8:2. For external validation, we used 893 images from 740 consecutive patients at 11 acute care hospitals suspected of having COVID-19 at the time of diagnosis. The dataset included 343 COVID-19 patients. The reference standard was RT-PCR. RESULTS: In external validation, the sensitivity and specificity of the model were 0.869 and 0.432, at the low-level cutoff, 0.724 and 0.721, at the high-level cutoff. Area under the receiver operating characteristic was 0.76. CONCLUSIONS: Our machine learning model exhibited a high sensitivity in external validation datasets and may assist physicians to rule out COVID-19 diagnosis in a timely manner at emergency departments. Further studies are warranted to improve model specificity.

[Oncology IVR--application to palliative medicine].

Oncology IVR is a minimum invasive and locoregional treatment by newly developed interventional techniques consisting of transarterial chemoembolization (TACE), radiofrequency ablation, cryoablation and percutaneous bone plasty (PBP), etc. These treatment methods are considered to be effective to rapid tumor reduction and palliation. The redistributed subclavian arterial infusion chemotherapy via an implanted catheter-port system which was newly developed by authors would be effective for local recurrence of breast cancer. The combination therapy of these interventional techniques can offer new treatment strategies for an improvement of patient's quality of life and more effective palliative medicine.

Nonselective Bilateral Embolization of Internal Iliac Arteries with N-Butyl-2-Cyanoacrylate in Hemodynamically Unstable Patients with Pelvic Fracture.

Purpose: This study was designed to evaluate the efficacy and safety of nonselective bilateral embolization of the internal iliac arteries (IIAs) with n-butyl-2-cyanoacrylate (NBCA) in hemodynamically unstable patients with pelvic fractures. Material and Methods: Twelve patients underwent nonselective bilateral embolization of the IIAs using NBCA diluted with lipiodol at our institution between January 2004 and March 2014. We analyzed the time of bilateral occlusion of the IIAs, the time from admission to entrance into the interventional radiology room, the need for repeat embolization, outcomes, cause of death, follow-up period, and complications. Results: The mean duration of bilateral occlusion of the IIAs was 17 min (range, 4-34 min), and the mean time from admission to entrance into the interventional radiology room was 89 min (range, 28-168 min). All patients underwent technically successful embolization. Repeat embolization was required after treatment in three patients. The mortality rate was 33.3%. Complications after embolization were suspected in one patient. Conclusions: Nonselective bilateral embolization of IIAs with NBCA could be a choice of treatment for hemodynamically unstable patients with severe pelvic fracture hemorrhage.

A Technical Improvement for Percutaneous Puncture of the Intervertebral disc by Passing Lateral to the Superior Articular Process Using the Isocenter Puncture Method.

Purpose: Percutaneous intervertebral disc puncture is useful in various situations. The isocenter puncture method enables easy, accurate, and safe punctures under fluoroscopic guidance. Herein, we present a clinical application of this technique that improves upon percutaneous puncture of intervertebral discs. Material and Methods: We performed percutaneous punctures of intervertebral discs slightly lateral to the superior articular process using the isocenter puncture method in 19 cases (10 men, 9 women; mean age, 64.5 years; range, 23-87 years). We assessed the technical success rate, procedure time, and complications. Results: We achieved successful punctures in all cases, with a median puncture time of 14.5 min (mean, 18.7 ± 11.3 min; range, 8-49 min). No patients complained of complications that were permanent or required treatment. Conclusions: Improved puncture of intervertebral discs seems to be possible using the isocenter puncture method.

Preloading Coil in Plug Method (p-CIP) with the AVP 2 for large Portosystemic Shunt Embolization.

Hepatic encephalopathy caused by a large portosystemic shunt (PSS) can be treated by endovascular embolization of the shunt. The PSS diameter can be >20 mm; it occasionally poses technical difficulties. Here, a 72-year-old woman with liver cirrhosis, hyperammonemia, and large spleno-renal shunt underwent shunt embolization using an Amplatzer vascular plug 2 (AVP2) and metallic coils. The preloading coil in plug method (p-CIP), which facilitated embolization inside the AVP2 without cannulation from outside, was employed to overcome technical difficulties. We propose the use of p-CIP with an AVP2 as a tool for treatment of hepatic encephalopathy with PSS.

C-arm cone beam CT for hepatic tumor ablation under real-time 3D imaging.

OBJECTIVE: We describe our experience with the application of a novel technology in which fluoroscopy and 3D imaging from C-arm cone beam CT systems are combined with integrated navigation software. CONCLUSION: We applied this technology to five cases in which radiofrequency ablation was performed for hepatocellular carcinoma. Technical success was achieved without treatment-related complications in all cases. We conclude that this novel technology is potentially useful for targeting hepatic lesions.

Endovascular retrieval of a Gunther-tulip vena cava filter migrated into the right atrium.

A 72-year-old male underwent placement of a Gunther-tulip vena cava filter to prevent development of a pulmonary embolism. One month later, when we tried to retrieve the Gunther-tulip vena cava filter via a transjugular approach, the filter detached from the snare and became free in the outer sheath. The Gunther-tulip vena cava filter did not reopen in the inferior vena cava probably because it became entangled with a thrombus; rather, the filter migrated into the right atrium. The filter orientation rendered the transjugular approach inappropriate; we used a bilateral transfemoral approach to aid filter retrieval. It is necessary to be very cautious when reopening a filter that has closed within the sheath. Although the filter migrated into the heart, we retrieved it using a combined approach.

Spinal Cord Infarction after Transcatheter Embolization of Pelvic Arteriovenous Malformation.

An 80-year-old woman presented with abdominal and right lower limb pain. Radiological examination revealed pelvic arteriovenous malformations (pAVMs). Although transarterial embolization was repeated, dilation of the common iliac vein worsened. Four sessions of embolization were performed for the internal iliac vein. Paraplegia gradually occurred a day after the final procedure. Magnetic resonance imaging revealed thoracic spinal cord edema and paraspinal vasodilatation, suggesting spinal cord infarction. Additional angiography revealed a radiculomedullary vein draining into the spinal canal from the pAVM; hence, surgical interruption was performed. Incomplete venous embolization of the pAVM caused spinal cord congestion and infarction.

Inferior mesenteric arteriovenous fistula during treatment with bevacizumab in colorectal cancer patient: A case report.

BACKGROUND: Fistula formation is a severe adverse event related to antiangiogenetic agents such as bevacizumab and inferior mesenteric arteriovenous fistula (IMAVF) is a result of acquired factor, especially colon surgery. However, IMAVF occurs very rarely and there are few reports in patients during chemotherapy. We report a case of a patient who developed IMAVF during treatment with bevacizumab in metastatic colorectal cancer (mCRC) after colon surgery. CASE SUMMARY: An 81-year-old man was diagnosed with descending colon cancer and underwent left hemicolectomy without any complications. He was definitely diagnosed with high-risk stage 2 and received tegafur-uracil plus leucovorin as adjuvant chemotherapy. Three years and 6 mo after the operation, the cancer relapsed with peritoneal dissemination. The patient underwent CyberKnife radiosurgery targeting the recurrent tumor and received chemotherapy with S-1 plus bevacizumab. At 1 year after chemotherapy, he complained of severe diarrhea, which is suspected drug-induced colitis. As diarrhea worsened despite the termination of treatment, he underwent colonoscopy and computed tomography (CT) scans that revealed edematous change from sigmoid to rectosigmoid colon. CT scans also revealed an aneurysm adjacent to the inferior mesenteric vein and multidetector CT angiography showed the IMAVF. Elective angiography confirmed the diagnosis of an IMAVF and it was successfully treated by arterial embolization. The patient resumed chemotherapy with only S-1 6 mo after embolization. CONCLUSION: Clinicians should keep in mind the probability of severe diarrhea arose from IMAVF in mCRC patients treated with bevacizumab.

Cost-Effectiveness Analysis of Percutaneous Vertebroplasty for Osteoporotic Compression Fractures.

STUDY DESIGN: Single-center, single-arm, prospective time-series study. OBJECTIVE: To assess the cost-effectiveness and improvement in quality of life (QOL) of percutaneous vertebroplasty (PVP). SUMMARY OF BACKGROUND DATA: PVP is known to relieve back pain and increase QOL for osteoporotic compression fractures. However, the economic value of PVP has never been evaluated in Japan where universal health care system is adopted. METHODS: We prospectively followed up 163 patients with acute vertebral osteoporotic compression fractures, 44 males aged 76.4±6.0 years and 119 females aged 76.8±7.1 years, who underwent PVP. To measure health-related QOL and pain during 52 weeks observation, we used the European Quality of Life-5 Dimensions (EQ-5D), the Rolland-Morris Disability Questionnaire (RMD), the 8-item Short-Form health survey (SF-8), and visual analogue scale (VAS). Quality-adjusted life years (QALY) were calculated using the change of health utility of EQ-5D. The direct medical cost was calculated by accounting system of the hospital and Japanese health insurance system. Cost-effectiveness was analyzed using incremental cost-effectiveness ratio (ICER): Δ medical cost/Δ QALY. RESULTS: After PVP, improvement in EQ-5D, RMD, SF-8, and VAS scores were observed. The gain of QALY until 52 weeks was 0.162. The estimated lifetime gain of QALY reached 1.421. The direct medical cost for PVP was ¥286,740 (about 3061 US dollars). Cost-effectiveness analysis using ICER showed that lifetime medical cost for a gain of 1 QALY was ¥201,748 (about 2154 US dollars). Correlations between changes in EQ-5D scores and other parameters such as RMD, SF-8, and VAS were observed during most of the study period, which might support the reliability and applicability to measure health utilities by EQ-5D for osteoporotic compression fractures in Japan as well. CONCLUSIONS: PVP may improve QOL and ameliorate pain for acute osteoporotic compression fractures and be cost-effective in Japan.

Preliminary findings of arterial embolization with balloon-occluded and flow-dependent histoacryl glue embolization in a swine model.

PURPOSE: To evaluate the potential usefulness of the balloon-occluded histoacryl glue embolization (B-glue) technique. MATERIALS AND METHODS: Both flow-dependent (no balloon occlusion) and B-glue techniques were used for 24 intercostal arteries of two female swine. N-butyl 2-cyanoacrylate (NBCA) was diluted with lipiodol to a 50 % solution, which was infused after occluding the arteries with microballoon catheters. The embolization range, fragmentation, reflux, adhesion, and glue particle attachment were compared between flow-dependent and B-glue techniques. RESULTS: The B-glue technique was performed in a controlled fashion resulting in successful arterial occlusion without fragmented migration of the injected glue cast. Reflux occurred less frequently with the B-glue technique and was significantly different (p = 0.039) [Corrected] from that for the flow-dependent technique. Catheters were safely removed from the arterial walls, although in one instance (8.3 %), large glue particles were found to be attached to the catheter tip on removal. Conversely, the flow-dependent technique was more difficult to control and resulted in several instances of higher rates of fragmentation. CONCLUSION: The B-glue technique can efficiently control NBCA delivery with lower rates of reflux.

Life-Saving Embolization in a Patient with Recurrent Shock Due to a Type II Endoleak after Endovascular Aortic Repair for a Ruptured Abdominal Aortic Aneurysm.

A man in his 80s underwent urgent endovascular aortic repair (EVAR) for a ruptured abdominal aortic aneurysm (RAAA). Surgery was completed without apparent complications, and the patient was returned to the Cardiac Care Unit. Two hours later, he again developed shock, and contrast-enhanced Computed Tomography showed extravasation from a type II endoleak (T2EL) involving the IMA. Transcatheter arterial embolization (TAE) was immediately performed, and the patient's vital signs stabilized soon after embolization. Abdominal compartment syndrome was suspected during the procedure, so a retroperitoneal hematoma evacuation was performed. The patient's postoperative course was satisfactory, and he transferred to another hospital. EVAR for RAAA would be useful, but it is necessary to be considered that T2EL can cause the aggravation of unstable circulation.

Embolization by Direct Puncture with a Transpedicular Approach Using an Isocenter Puncture (ISOP) Method in a Patient with a Type II Endoleak After Endovascular Aortic Repair (EVAR).

BACKGROUND: Endovascular aortic repair (EVAR) requires further intervention in 20-30 % of cases, often due to type II endoleak (T2EL). Management options for T2EL include transarterial embolization, direct puncture (DP), or transcaval embolization. We report the case of an 80-year-old man with T2EL who successfully underwent DP embolization. METHODS: Embolization by DP was performed with a transpedicular approach using an isocenter puncture (ISOP) method. An isocenter marker (ICM) was placed at a site corresponding to the aneurysm sac on fluoroscopy in two directions (frontal and lateral views). A vertebroplasty needle was inserted tangentially to the ICM under fluoroscopy and advanced to the anterior wall of the vertebral body. A 20 cm-length, 20-G-PTCD needle was inserted through the outer needle of the 13-G needle and advanced to the ICM. Sac embolization using 25 % N-buty-2-cyanoacrylate diluted with Lipiodol was performed. After complete embolization, rotational DA confirmed good filling of the sac with Lipiodol. The outer cannula and 13-G needle were removed and the procedure was completed. RESULTS: The patient was discharged the next day. Contrast-enhanced computed tomography 1 and 8 months later showed no Lipiodol washout in the aneurysm sac, no endoleak recurrence, and no expansion of the excluded aneurysm. CONCLUSION: DP with a transpedicular approach using ISOP may be useful when translumbar and transabdominal approaches prove difficult.

Guidelines for the use of NBCA in vascular embolization devised by the Committee of Practice Guidelines of the Japanese Society of Interventional Radiology (CGJSIR), 2012 edition.

Cyanoacrylates are a group of fast-acting adhesives. They form low viscosity liquids in the monomer state and instantly polymerize to become adhesive upon contact with ionic substances. Since the 1950s, they have been used around the world for industrial and household purposes. N-butyl cyanoacrylate (NBCA) is a cyanoacrylate that is commonly used for medical care, and the closure of skin wounds with NBCA has been found to promote hemostasis. However, in Japan, the intravascular injection of NBCA is considered to be off-label use, except during the treatment of gastric varices under endoscopy. The use of NBCA in embolotherapy is considered when the target vessels cannot be cannulated superselectively, for vascular diseases that require long segments of the target vessel to be embolized, or for patients in a hypocoagulable state. NBCA-based embolotherapy can be used to treat vascular malformations, acute hemorrhaging, tumors, and venous disease. The complications associated with NBCA-based embolotherapy include tissue ischemia, hemorrhaging, systemic or local reactions, and catheter adhesion to blood vessels. NBCA is mixed with Lipiodol to make it radiopaque and to adjust its polymerization time. Since there are various technical aspects to performing NBCA-based embolotherapy safely, it should be carried out by, or with the assistance of, proficient interventional radiologists.

A case of pseudoaneurysm of the deep femoral artery successfully treated by NBCA embolization under occlusion.

Transcatheter embolization of bleeding from distal branches of small arteries can be difficult. N-butyl cyanoacrylate (NBCA) was originally used as a tissue adhesive material, and recent evidence suggests that it can also be used as an embolic material. This report describes a case in which a pseudoaneurysm arising from the distal portion of a small branch of the deep femoral artery was successfully embolized with NBCA using a new technique with a microballoon catheter. Advantages of this technique include its safely, short treatment time, good control of the embolization range, absence of fragmentation, favorable polymerization dynamics, and absence of glue reflux or excessive distal spread of the glue.