Head and Neck Arteriovenous Malformations: Clinical Manifestations and Endovascular Treatments.

Arteriovenous malformations (AVMs) are vascular malformations that present high-flow direct communication between the arteries and veins, not involving the capillary beds. They can be progressive and lead to various manifestations, including abnormal skin or mucosal findings, ischemia, hemorrhage, and high-output heart failure in severe cases. AVMs often involve the head and neck region. Head and neck AVMs can present region-specific clinical manifestations, angioarchitecture, and complications, especially in cosmetic appearance and ingestion, respiratory, and neuronal functions. Therefore, when planning endovascular treatment of head and neck AVMs, physicians should consider not only the treatment strategy but also the preservation of the cosmetic appearance and critical functions. Knowledge of the functional vascular anatomy as well as treatment techniques should facilitate a successful management. This review summarizes AVMs' clinical manifestations, imaging findings, treatment strategy, and complications.

Value of fat-suppressed T2-weighted imaging for predicting short-term pain relief after sclerotherapy for venous malformations in the extremities.

PURPOSE: This study aimed to evaluate the value of fat-suppressed T2-weighted imaging (FS-T2WI) for predicting short-term pain relief after polidocanol sclerotherapy for painful venous malformations (VMs) in the extremities. MATERIALS AND METHODS: This retrospective study included patients with painful VMs in the extremities between October 2014 and September 2021, had their first sclerotherapy without history of surgical therapy, and underwent magnetic resonance imaging before sclerotherapy. Pain relief was assessed 2 months after 3% polidocanol sclerotherapy and was categorized as follows: progression, no change, partial relief, or free of pain. The associations between pain relief and imaging features on FS-T2WI were analyzed. RESULTS: The study included 51 patients. The no change, partial relief, and free of pain groups included 6 (11.8%), 25 (49.0%), and 20 (39.2%) patients, respectively. No patient experienced progressive pain. The lesion diameter was ≤ 50 mm in 13 (65.0%) patients in the free of pain group, whereas it was > 50 mm in all patients in the no change group (p = 0.019). The lesions showed well-defined margin in 15 (75.0%) patients in the free of pain group, whereas they showed ill-defined margin in 5 (83.3%) patients in the no change group (p = 0.034). The most common morphological type was cavitary in the free of pain group (14 [70.0%] patients), whereas there was no patient with cavitary type lesion in the no change group (p = 0.003). Drainage vein was demonstrated in 6 (100%), 22 (88.0%), and 11 (55.0%) patients in the no change, partial relief, and free of pain group, respectively (p = 0.011). CONCLUSION: A lesion size of 50 mm or less, a well-defined margin, a cavitary type, and no drainage vein on FS-T2WI were significant features for predicting short-term pain relief after polidocanol sclerotherapy for painful VMs in the extremities.

Utility of non-contrast-enhanced magnetic resonance imaging in predicting preoperative clinical stage and prognosis in patients with thymic epithelial tumor.

PURPOSE: The purpose of this study was to find useful imaging features on non-contrast-enhanced magnetic resonance imaging (MRI) that can divide patients with thymic epithelial tumor (TET) into clinical stage I-II and III-IV groups under assumption that contrast media are contraindicated. MATERIALS AND METHODS: This retrospective study included 106 patients (median age, 60 years; range, 27-82 years; 62 women) with surgically resected TET who underwent MRI between August 1986 and July 2015. All cases were classified according to the 2015 WHO classification and staged using the eighth edition of the TNM system. Two radiologists independently evaluated 14 categories of MRI findings; the findings in patients with stage I-II were compared with those of patients with stage III-IV using a logistic regression model. Disease-specific survival associated with significant findings was calculated using the Kaplan-Meier method. RESULTS: Univariate analysis showed that stage III-IV patients were more likely to have tumors with an irregular contour, heterogeneity on T1WI, low-signal intensity on T2WI, irregular border with lung, findings of great vessel invasion (GVI) (hereafter, GVI sign), pericardial thickening/nodule, and lymphadenopathy (all, P < 0.01). On multivariable analysis, only two findings, irregular border between tumor and lung (odds ratio [OR], 272.8; 95% CI 26.6-2794.1; P < 0.001) and positive GVI sign (OR, 49.3; 95% CI 4.5-539.8; P = 0.001) remained statistically significant. Patients with one or both features had significantly worse survival (log-rank test, P < 0.001). CONCLUSION: For patients with TET who are unable to receive contrast for preoperative staging, the two image findings of an irregular border between tumor and lung and the positive GVI sign on non-contrast-enhanced MRI could be helpful in determining stage III-IV disease which is associated with a worse survival.

Super-selective and staged glue embolization for labral AVMs using ultra-thin microcatheters: report of two cases.

BACKGROUND: Treating arteriovenous malformation (AVM) is challenging because of the high recurrence rate and because incomplete resection or embolization can induce aggressive growth. However, a standard strategy is not fully established. Although transcatheter arterial embolization (TAE) is currently almost always part of the treatment, in many cases, single treatment is not curative and only palliative. Additionally, the success and complication rates associated with TAE alone are unclear, and there has been limited study of staged TAE for facial AVMs. Furthermore, few reports have described the details of the procedure. CASE-PRESENTATION: We report two cases of AVM of the upper lip in patients who were successfully treated by staged super-selective TAE at several-month intervals using ultra-thin microcatheters and n-butyl-2-cyanoacrylate. CONCLUSION: Staged and super-selective TAE may prevent complications and provide high curability and might be a useful treatment in cases of AVM.

Stent graft placement guided by intravascular ultrasound for subclavian artery dissecting aneurysm.

Subclavian artery dissecting aneurysm is relatively rare and can be caused by traumatic, nontraumatic, and iatrogenic etiologies. Surgical management of subclavian artery dissecting aneurysm has been sparsely reported. Recently, due advances in endovascular techniques making them less invasive, these approaches have become more standard as treatments. Subclavian artery dissecting aneurysm management usually depends on whether there is ischemia of the tissues supplied by the subclavian artery. Furthermore, treatment strategies depend on which section of the artery is involved. In particular, treatment is difficult if the dissecting aneurysm has branching vessels. In this case report, we show that endovascular repair using a covered stent graft is a promising approach to repair a subclavian artery dissecting aneurysm. In this case, the stent graft was highly effective, and follow-up examinations showed good patency of the subclavian artery. Additional use of IVUS (Volcano Inc.; Rancho Cordova, CA, USA) is helpful to obtain the precise location of the true lumen of a dissecting aneurysm.

Internal coil packing method for the Amplatzer vascular plug 4.

The Amplatzer vascular plugs (AVPs), including AVP 4, have excellent occlusion; however, insufficient embolization or recanalization may occasionally occur. This study aimed to evaluate the feasibility and effectiveness of internal coil packing method to insert microcoils into the AVP 4 using an experimental vascular model. The insertion of a 1.7 F microcatheter through the nitinol mesh of the AVP 4 was not possible. Only 0.010-inch electrolytic detachable microcoils could be inserted through catheter tips in contact with nitinol mesh. The internal coil packing of the AVP 4 may be accomplished by inserting 0.010-inch microcoils into the AVP 4 in cases of continued perfusion or recanalization with required short-segment embolization.

A Rare Case of Cerebral Air Embolism Caused by Pulmonary Arteriovenous Malformation After Removal of a Central Venous Catheter.

Cerebral air embolism following central venous catheter (CVC) removal is extremely rare. We report a case of cerebral air embolism with loss of consciousness after removal of CVC caused by pulmonary arteriovenous malformation (PAVM). Computed tomography revealed air bubbles in the internal carotid arteries along the sulci in the cerebral hemispheres, as well as a PAVM. The cerebral air embolism was treated with hyperbaric oxygen and intravenous thrombolytic therapy, and transcatheter embolization of the PAVM was performed. When inserting/removing CVC in a patient with a small PAVM, treatment of the PAVM, irrespective of its size, could prevent the type of complication that occurred in our present case.

Treatment of a Large Pharyngeal Venous Malformation using Transoral Sclerotherapy.

Management of venous malformation (VM) in the pharynx is challenging because of difficulties in needle access and the presence of nerves as well as other critical anatomical structures around the lesion. We describe the successful treatment of a large pharyngeal VM using transoral sclerotherapy. The patient, a 21-yearold male, visited our hospital for sclerotherapy treatment consultation after complaining of difficulty in swallowing because of a pharyngeal VM. Transoral sclerotherapy was successful, and the symptoms showed complete alleviation. Using a flat detector-equipped angiographic C-arm CT (CACT) enabled the precise assessment of sclerosant placement, facilitating safer sclerotherapy in the pharynx.

A Retrograde Transvenous Embolization Technique with Balloon-Assisted Arterial Aspiration for a Peripheral Arteriovenous Malformation with a Venous Pouch.

Management of arteriovenous malformations (AVMs) is challenging, and there is no consensus regarding either the ideal approach or the treatment timing. Percutaneous embolization is the most frequent approach currently used and is considered the first-line technique for AVMs. There is an ongoing discussion about the best technical approach to embolize AVMs. AVMs associated with a dominant outflow vein (DOV) are rare. Embolization of both the DOV and the nidus is considered more effective. Herein, we report a novel technique of transvenous embolization of a DOV under negative pressure from an arterial balloon catheter in a case of a peripheral AVM. This technique allows the embolization of the DOV and the nidus retrogradely.

Ultraselective embolization using a 1.7-Fr catheter and soft bare coil for small intestinal bleeding.

OBJECTIVE: We aimed to evaluate the safety and efficacy of embolization using a 1.7-Fr catheter and soft bare coil to treat acute small intestinal bleeding. MATERIAL AND METHODS: Subjects were five consecutive patients who experienced onset of melena with small intestinal bleeding and underwent transcatheter arterial embolization with 1.7-Fr catheters and 0.010-inch detachable bare coils (five procedures in total). Technical success, clinical success, relative post-procedural complications, arterial bleeding source and cause, and relationship between coagulopathy and embolization efficacy were examined by capsule endoscopy. RESULTS: We achieved 100% technical and clinical success for the five transcatheter arterial embolizations. All catheterizations of the vasa recta of the bleeding artery (jejunal artery, n = 2; ileal artery, n = 3) were possible with a 1.7-Fr catheter. We achieved high embolization efficacy in two patients with coagulopathy. No rebleeding, intestinal ischemia, or necrosis was observed on follow-up capsule endoscopy. We confirmed that peptic ulcers/ulcer scars were the cause of bleeding for all patients. CONCLUSION: Embolization with 0.010-inch coils using a 1.7-Fr catheter and catheterization of the vasa recta of bleeding vessels was effective and safe for treating small intestinal bleeding.

Endovascular Management of Intractable Postpartum Hemorrhage Caused by Vaginal Laceration.

PURPOSE: We evaluated the management of transcatheter arterial embolization for postpartum hemorrhage caused by vaginal laceration. MATERIALS AND METHODS: We reviewed seven cases of patients (mean age 30.9 years; range 27-35) with intractable hemorrhages and pelvic hematomas caused by vaginal lacerations, who underwent superselective transcatheter arterial embolization from January 2008 to July 2014. Postpartum hemorrhage was evaluated by angiographic vascular mapping to determine the vaginal artery's architecture, technical and clinical success rates, and complications. RESULTS: The vaginal artery was confirmed as the source of bleeding in all cases. The artery was found to originate from the uterine artery in three cases, the uterine and obturator arteries in two, or the internal pudendal artery in two. After vaginal artery embolization, persistent contrast extravasation from the inferior mesenteric artery as an anastomotic branch was noted in one patient. Nontarget vessels (the inferior vesical artery and nonbleeding vaginal arterial branches) were embolized in one patient. Effective control of hemostasis and no post-procedural complications were confirmed for all cases. CONCLUSION: Postpartum hemorrhages caused by vaginal lacerations involve the vaginal artery arising from the anterior trunk of the internal iliac artery with various branching patterns. Superselective vaginal artery embolization is clinically acceptable for the successful treatment of vaginal laceration hemorrhages, with no complications. After vaginal artery embolization, it is suggested to check for the presence of other possible bleeding vessels by pelvic aortography with a catheter tip at the L3 vertebral level, and to perform a follow-up assessment.

Emergent interventional approach for aortogastric tube fistula with massive gastrointestinal bleeding.

This report describes the successful endovascular treatment of a rare case of aortogastric tube fistula with massive gastrointestinal haemorrhage. The patient's history included oesophageal reconstruction for oesophageal carcinoma using a gastric tube. Emergent angiography revealed extravasation from the thoracic aorta into the thinner aortogastric tube fistula. A microcatheter was inserted into the aortogastric tube with the aortic approach for embolisation with a mixture of n-butyl cyanoacrylate and iodised oil to enable fluoroscopic visualisation. Aortography confirmed the complete absence of extravasation after embolisation, after which a stent graft was placed. This procedure demonstrated that transcatheter embolisation of the aortogastric tube fistula was possible, and that the technique can be used as an emergency option. CT imaging was performed 21 days after the procedure, and revealed no trace of extravasation or inflammation. There were no complications during the 14 months following the endovascular treatment; the patient remains in stable condition.

Management of visceral artery embolization using 0.010-inch detachable microcoils.

Transcatheter coil embolization is used primarily to treat arterial hemorrhages, tumors, aneurysms, and vascular malformations. However, conventional microcatheter systems cannot always be employed in difficult cases. In this technical note, we describe how small-diameter primary coils and microcatheter tips that are thinner than normal can be used to increase the safety and reliability of coil embolization.

Follow-up of true visceral artery aneurysm after coil embolization by three-dimensional contrast-enhanced MR angiography.

PURPOSE: We aimed to evaluate the outcomes of coil embolization of true visceral artery aneurysms by three-dimensional contrast-enhanced magnetic resonance (MR) angiography. MATERIALS AND METHODS: We used three-dimensional contrast-enhanced MR angiography, which included source images, to evaluate 23 patients (mean age, 60 years; range, 28-83 years) with true visceral artery aneurysms (splenic, n=15; hepatic, n=2; gastroduodenal, n=2; celiac, n=2; pancreaticoduodenal, n=1; gastroepiploic, n=1) who underwent coil embolization. Angiographic aneurysmal occlusion was revealed in all cases. Follow-up MR angiography was conducted with either a 1.5 or 3 Tesla system 3-25 months (mean, 18 months) after embolization. MR angiography was evaluated for aneurysmal occlusion, hemodynamic status, and complications. RESULTS: Complete aneurysmal occlusion was determined in 22 patients (96%) on follow-up MR angiography (mean follow-up period, 18 months). Neck recanalization, which was observed at nine and 20 months after embolization, was confirmed in one of eight patients (13%) using a neck preservation technique. In this patient, a small neck recanalization covered by a coil mass was demonstrated. The complete hemodynamic status after embolization was determined in 21 patients (91%); the visualization of several collateral vessels, such as short gastric arteries, after parent artery occlusion was poor compared with that seen on digital subtraction angiography in the remaining two patients (9%). An asymptomatic localized splenic infarction was confirmed in one patient (4%). CONCLUSION: Our study presents the follow-up results from three-dimensional contrast-enhanced MR angiography, which confirmed neck recanalization, the approximate hemodynamic status, and complications. This effective and less invasive method may be suitable for serial follow-up after coil embolization of true visceral aneurysms.

A newly developed double lumen microballoon catheter with a side hole: initial experience of intraarterial infusion chemotherapy and/or embolization.

PURPOSE: To introduce a newly developed double lumen microballoon catheter with a side hole for intraarterial infusion chemotherapy and/or embolization. METHODS AND MATERIALS: Seven patients with malignant tumors, for whom superselective catheterization was considered difficult or had failed, underwent intraarterial infusion chemotherapy and/or embolization with the 3.3-Fr microballoon catheter. The catheter has a double lumen and a side hole to facilitate infusion from the proximal end of the balloon. The balloon was placed on the distal side of the target artery branching site. Inflation of the balloon and occlusion of the main lumen with the tip of the occlusion device allowed for intraarterial infusion chemotherapy and/or embolization of the target artery via the side hole. RESULTS: Successful intraarterial infusion chemotherapy and/or embolization with the microballoon catheter was performed in all patients with no complications. CONCLUSIONS: The newly developed microballoon catheter achieves intraarterial infusion chemotherapy and/or embolization without the need for superselective catheterization.