Hepatic Hilar Nerve Block for Adjunctive Analgesia during Percutaneous Thermal Ablation of Hepatic Tumors: A Retrospective Analysis.

PURPOSE: To determine whether hepatic hilar nerve block techniques reduce analgesic and sedation requirements during percutaneous image-guided thermal ablation of hepatic tumors. MATERIALS AND METHODS: A single-center retrospective cohort analysis was performed of 177 patients (median age, 67 years; range, 33-86 years) who underwent percutaneous image-guided thermal ablation of liver tumors. All patients were treated utilizing local anesthetic and moderate sedation between November 2018 and November 2021 at a tertiary level hospital, with or without the administration of a hepatic hilar nerve block. Univariable and multivariable linear regression analyses were performed to determine the relationship between the administration of the hilar nerve block and fentanyl and midazolam dosages. RESULTS: A total of 114 (64%) patients received a hilar nerve block in addition to procedural sedation, and 63 (36%) patients received procedural sedation alone. There were no significant differences in the baseline demographic and tumor characteristics between the cohorts. The procedure duration was longer in the hilar block cohort than in the unblocked cohort (median, 95 vs 82 minutes; P = .0012). The technical success rate (98% in both the cohorts, P = .93) and adverse event rate (11% vs 3%, P = .14) were not significantly different between the cohorts. After adjusting for patient and tumor characteristics, ablation modality, and procedure and ablation durations, hilar nerve blocks were associated with lower fentanyl (-18.4%, P = .0045) and midazolam (-22.7%, P = .0007) dosages. CONCLUSIONS: Hepatic hilar nerve blocks significantly decrease the fentanyl and midazolam requirements during thermal ablation of hepatic tumors, without a significant change in the technical success or adverse event rates.

Vancouver General Hospital Pulmonary Embolism Response Team (VGH PERT): initial three-year experience.

PURPOSE: Clinical equipoise exists with the use of novel reperfusion therapies such as catheter-directed thrombolysis in the management of patients presenting to hospital with high risk pulmonary embolism (PE). Therapeutic options rely on clinical presentation, patient factors, physician preference, and institutional availability. We established a Pulmonary Embolism Response Team (PERT) to provide urgent assessment and multidisciplinary care for patients presenting to our institution with high-risk PE. METHODS: Data were retrospectively collected from PERT activations between January 2016 and December 2018. Chi square tests were used to determine differences in mortality across the three years of study. Logistic regression was used to evaluate 30- and 90-day mortality and occurrence of major bleeds between those receiving anticoagulation alone (AC) and those receiving advanced reperfusion therapy (ART). RESULTS: There were 128 PERT activations over three years, the majority originating from the emergency department. Eighty-five percent of activations were for submassive PE, with 56% of all activations assessed as submassive-high risk. Fifteen patients (12%) presented with massive PE. Advanced reperfusion therapy was used in 29 (23%) patients, of whom 25 (20%) received catheter-directed thrombolysis. There was an increased risk of major bleeding in the ART group compared with in the AC group (odds ratio [OR], 17.9; 95% confidence interval [CI], 4.1 to 125.0; P < 0.001), but no increased risk of mortality at 30 days (OR, 2.1; 95% CI, 0.4 to 9.1; P = 0.3). The 30-day mortality rate was 7.8%. CONCLUSION: We describe the first Canadian PERT, a multidisciplinary team aimed at providing urgent individualized care for patients with high-risk PE. Further research is necessary to determine whether a PERT improves clinical outcomes.

RéSUMé: OBJECTIF: Le concept d'équilibre clinique existe lors de l'utilisation de traitements innovants de reperfusion tels que la thrombolyse in situ (ou thrombolyse par cathéter) pour la prise en charge des patients se présentant à l'hôpital avec une embolie pulmonaire (EP) à haut risque. Les options thérapeutiques s'appuient sur la présentation clinique, les caractéristiques du patient, la préférence du médecin et la disponibilité institutionnelle. Nous avons mis sur pied une Équipe d'intervention en cas d'embolie pulmonaire (PERT - Pulmonary Embolism Response Team) afin de fournir une évaluation urgente et des soins multidisciplinaires aux patients se présentant dans notre institution avec une EP à haut risque. MéTHODE: Nous avons récolté rétrospectivement les données concernant les activations/alertes reçues par notre PERT entre janvier 2016 et décembre 2018. Des tests de chi carré ont été utilisés afin de déterminer les différences en matière de mortalité au cours des trois années de durée de l'étude. La régression logistique a été utilisée pour évaluer la mortalité à 30 et à 90 jours ainsi que la survenue de saignements majeurs entre les patients recevant uniquement un traitement anticoagulant (AC) et ceux recevant un traitement de reperfusion avancé (TRA). RéSULTATS: Il y a eu 128 alertes requérant l'activation de notre PERT en trois ans, la majorité provenant de l'urgence. Quatre-vingt-cinq pour cent des activations concernaient des EP submassives, et 56 % de toutes les activations ont été évaluées comme étant submassives à haut risque. Quinze patients (12 %) se sont présentés avec une EP massive. Un traitement de reperfusion avancé a été administré à 29 (23 %) patients, parmi lesquels 25 (20 %) ont reçu une thrombolyse in situ. Un risque accru de saignement majeur a été observé dans le groupe TRA par rapport au groupe AC (rapport de cotes [RC], 17,9; intervalle de confiance [IC] 95 %, 4,1 à 125,0; P < 0,001), mais il n'y avait pas de risque accru de mortalité à 30 jours (RC, 2,1; IC 95 %, 0,4 à 9,1; P = 0,3). Le taux de mortalité à 30 jours était de 7,8 %. CONCLUSION: Nous décrivons la première PERT canadienne, une équipe multidisciplinaire ayant pour but de prodiguer des soins personnalisés urgents aux patients avec embolie pulmonaire à haut risque. Des recherches supplémentaires sont nécessaires pour déterminer si une PERT améliore les pronostics cliniques.

Sclerotherapy with Adjunctive Stasis of Efflux (STASE) in Venous Malformations: Techniques and Strategies.

Venous malformations are very commonly encountered in interventional radiologic practice. Indications for therapy are clearly defined based on the lesion's impact on patient's quality of life. Screening laboratory coagulation studies in patients with historical or lesion morphologic risk factors often reveal abnormal coagulation parameters consistent with localized intravascular coagulation or more severe coagulopathic states. These may require chronic or periprocedural medical management to avoid potentially life-threatening disseminated intravascular coagulation or other thromboembolic phenomena. Once a multidisciplinary decision to treat a venous malformation is made, one must decide between percutaneous and/or surgical techniques. Sclerotherapy with adjunctive stasis of efflux (STASE) techniques have become the mainstay of therapy for most venous malformations as they are well-tolerated and effective. STASE techniques work primarily by (i) the administration of sclerosant(s) exerting an inhibitory and/or endotheliocidal effect on venous malformation endothelium leading to thrombosis, involution, and fibrosis, and secondarily via adjunctive outflow occlusion using any combination of local compression, balloons, gelatin, coils, laser, radiofrequency, or adhesives to improve sclerosant penetration and dwell-time in the lesion. Adhesives alone can fill the lesion to facilitate surgical resection in some cases. Common sclerosants in modern practice include sodium tetradecyl sulfate, bleomycin, polidocanol, ethanol, and hypertonic saline. Most agents can be given directly in unmodified or "neat" form or can be mixed with a gas to form a sclerofoam or embolic such as gelatin to form a sclerogel. Choice and method of sclerosant delivery in each patient is based on the intraluminal lesion volume, architecture, vital structure proximity, agent toxicity, viscosity, and level of experience of the interventional radiologist with that particular agent. Multi-session STASE therapy usually reduces symptoms of chronic pain or mass with low risk of known complications of skin or nerve impairment, compartment syndrome, hemoglobinuria, deep venous thrombosis, or pulmonary phenomena.

Transapical Coil Embolization of a Postsurgical Ascending Thoracic Aortic Pseudoaneurysm.

Ascending aortic pseudoaneurysms are a rare but potentially life-threatening complication of aortic root or cardiac surgery. Surgical repair is established as first-line treatment; however, patient comorbidities, technical considerations, and anatomic limitations often preclude patients from repeat surgery, thus necessitating alternative approaches. Here, we present a case of coil embolization of an ascending aortic pseudoaneurysm via a transapical approach in a particularly complex scenario where percutaneous and peripheral access was technically unfeasible.

Prospective Study on Total Fluoroscopic Time in Patients Undergoing Uterine Artery Embolization: Comparing Transradial and Transfemoral Approaches.

PURPOSE: Comparing total fluoroscopy time (FT) to perform uterine artery embolization (UAE) with transradial approach (TRA) versus transfemoral approach (TFA). Our hypothesis was that there would be no significant procedural time penalty incurred, despite the learning curve associated with adopting a new approach. MATERIALS AND METHODS: A cohort study was undertaken including 66 consecutive patients undergoing UAE with either TRA/TFA between January and September 2015. Total FT was recorded prospectively for each procedure, and data subsequently analyzed retrospectively. Each operator had at least 2 years of experience as an interventional radiologist having performed at least 200 TFA UAEs. All operators had recently incorporated TRA into their practice. RESULTS: A total of 39 TFA and 27 TRA cases were included in the study; mean age for TFA group was 44.4 years (± 4.9) and for TRA group was 45.1 years (± 4.9) (p = 0.59). Mean FTs were comparable between the two groups (p = 0.86) despite a learning curve associated with TRA: The mean total FT with TFA was 20.36 min (± 9.48) compared to TRA 20.12 min (± 7.67). CONCLUSIONS: FTs for TRA UAE were comparable to TFA UAE, even though TRA had been recently adopted as a new approach. Despite the learning curve associated with developing a novel technique, operators should not expect the efficiency of their service to be significantly compromised. Introducing this safe and effective method of vascular access should therefore be considered.

Transradial Access for Interventional Radiology: Single-Centre Procedural and Clinical Outcome Analysis.

PURPOSE: The study sought to describe a single centre's technical approach to transradial intervention and report on clinical outcomes and safety. METHODS: A total of 749 transradial access (TRA) procedures were performed at a single hospital in 562 patients (174 women and 388 men). Procedures included 445 bland embolizations or chemoembolizations of the liver, 88 uterine artery embolizations, and 148 procedures for Selective Internal Radiation Therapy (Y90), which included mapping and administration. The mean age of the patients was 62 years (range 27-96 years). RESULTS: Four cases (0.5%) required crossover to transfemoral (tortuous anatomy, inability to secure a stable position for embolization, vessel spasm and base catheter not being of a sufficient length). A single asymptomatic, short-segment radial artery occlusion occurred (0.3%), 3 patients (0.4%) developed small hematomas postprocedurally, and 2 patients (0.7%) had transient neurological pain, which was resolved within a week without treatment. It was found that 98% of patients who had a previous femoral access procedure would choose radial access for subsequent procedures. CONCLUSIONS: Transradial access is a safe, effective technique, with a learning curve; however, this procedure has the potential to significantly improve departmental workflow and cost savings for the department and patient experience.

A Step-by-Step Practical Approach to Imaging Diagnosis and Interventional Radiologic Therapy in Vascular Malformations.

Within vascular anomalies, vascular malformations are those present at birth that grow with the patient and exhibit abnormal dilated vascular channels lined by mature endothelium. Vascular tumors, the other group of vascular anomalies, demonstrate endothelial hypercellularity. Vascular malformations are further divided into low-flow varieties (capillary, venous, and lymphatic malformations) and high-flow varieties (arteriovenous malformation and fistula). All malformations exhibit a predictable group of clinical patterns that vary in severity and rate of progression. The interventional radiologist must incorporate this clinical data with characteristic ultrasound and magnetic resonance findings to arrive at a diagnosis. One must then decide in a multidisciplinary fashion, based on objective clinical criteria and image-based morphology, if the patent is a candidate for intervention. Sclerotherapy is a technique used to treat vascular malformations whereby an endothelial-cidal agent is introduced into the endoluminal compartment to initiate vascular closure. The high flow rate of an arteriovenous malformation requires the incorporation of superselective transarterial, direct, and transvenous access with flow reduction techniques to deliver adequate dose of sclerosant and embolic to the nidus. Satisfactory outcomes are seen in over half of all malformations patients. Similar treatment-related complications are seen between malformations but are lowest in lymphatic and highest in arteriovenous malformations.

Spinal injection procedures: a review of concepts, controversies, and complications.

The field of spinal injection procedures is growing at a tremendous rate. Many disciplines are involved, including radiology, anesthesiology, orthopedics, physiatry and rehabilitation medicine, as well as other specialties. However, there remains tremendous variability in the assessment of patients receiving these therapies, methods for evaluation of outcome, and in the understanding of where these procedures belong in the triaging of those who require surgery. In this article, we attempt to highlight the biologic concepts on which these therapies are based, controversies that have arisen with their increasing use, and a description of complications that have been reported.

Venous malformations: classification, development, diagnosis, and interventional radiologic management.

Venous malformations are categorized as low-flow vascular malformations within the domain of vascular anomalies and are the most common vascular malformation encountered clinically. Venous malformations are by definition present at birth, undergo pari passu growth, and present clinically because of symptoms related to mass effect or stasis. Although diagnosis can usually be made by clinical history and examination, differentiation from other vascular and nonvascular entities often requires an imaging work-up that includes ultrasound, CT, MR imaging, and diagnostic phlebography. All decisions regarding imaging work-up and decision to treat must be coordinated though referral and discussions with a multidisciplinary team and be based on clearly defined clinical indications. Percutaneous image-guided sclerotherapy has become the mainstay of treatment for venous malformations and involves the introduction of any one of a number of endothelial-cidal sclerosants into the vascular spaces of the lesion, with each sclerosant possessing its own unique spectrum of advantages and disadvantages.

The current status of percutaneous vertebroplasty in Canada.

OBJECTIVE: To provide an overview of the current status of percutaneous vertebroplasty (PVP) practice in Canada, including the preprocedure work up, operative technique and follow-up practice of physicians performing the procedure in this country. METHODS: Questionnaires were emailed to 31 institutions performing percutaneous vertebroplasty across Canada. RESULTS: Twenty-three (74.2%) completed surveys were returned, representing data from 1516 vertebroplasties performed by 66 radiologists and surgeons. Preoperative routine imaging and screening practice varies widely. The majority of respondents perform PVP under conscious sedation; however, an anaesthetist is present in only 22% of institutions. Biplane fluoroscopy is used in 43.5% of practices. The preference for unipedicular or bipedicular injection varies: in 7 institutions, a unipedicular approach is used in at least 80% of cases. Patients receive a follow-up by the screening physician in 65.2% of institutions. There were 4 complications requiring treatment. Venous and intradiscal extravasation rates were 20.8% and 25.3%, respectively; however, the vast majority of these were clinically insignificant. CONCLUSION: PVP complication rates reported in our Canadian survey compare favourably with those in the published literature. The number of PVPs performed annually in the institutions surveyed appears small, relative to the figures from the United States. The prevalence of osteoporosis and incidence of vertebral compression fractures in Canada is increasing as the population ages, and demand for PVP is likely to rise significantly in the coming years.

Pseudoaneurysm of the superior gluteal artery following polytrauma.

Gluteal artery aneurysms are rare and often secondary to pelvic fractures, blunt or penetrating trauma. We describe a case of a superior gluteal artery pseudoaneurysm that presented as back pain with numbness and weakness of the lower extremities. Diagnosis was confirmed by color Doppler sonography and angiography. A proximal and distal control was obtained over the aneurysm neck via coil embolization with excellent hemostasis within the pseudoaneurysm and maintenance of perfusion to the left pelvis.

Uterine arteriovenous malformations: from diagnosis to treatment.

OBJECTIVE: The purpose of this study was to describe the sonographic features of uterine arteriovenous malformations (AVMs) and to describe the role and clinical outcome after transcatheter arterial embolization of symptomatic uterine AVMs. METHODS: In our institution, over a 4-year period, symptomatic uterine AVMs were diagnosed in 21 women. Endovaginal sonography with gray scale, color, and spectral Doppler imaging was performed on all patients. Fourteen patients required therapeutic angiography/embolization to control bleeding. These 14 patients had follow-up endovaginal sonography 24 hours after the procedure. RESULTS: The sonographic gray scale findings of uterine AVMs were nonspecific. The most common finding was subtle myometrial heterogeneity (n = 14), whereas other patients had small anechoic spaces in the myometrium (n = 7). Color Doppler sonography showed a tangle of vessels with multidirectional high-velocity flow that produced a "color mosaic" pattern. Spectral Doppler analysis showed arteriovenous shunting with high-velocity, low-resistance flow. Fourteen patients required transcatheter arterial embolization to control bleeding. Thirteen of 14 patients had no sonographic evidence of a residual AVM 24 hours after the procedure. One of 14 patients had a residual AVM requiring additional embolization. One patient had recurrent bleeding at 4 months and required further embolization. The remaining 7 patients were treated conservatively. CONCLUSIONS: Endovaginal sonography is the imaging modality of choice in patients with abnormal uterine bleeding. Routine use of color and spectral Doppler sonography allows one to confidently make the correct diagnosis. Transcatheter arterial embolization is an excellent treatment option. Endovaginal sonography should be used to monitor postembolization outcomes.

Current concepts and techniques in percutaneous vertebroplasty.

Percutaneous vertebroplasty is a safe and effective alternative for the treatment of many different types of painful vertebral lesions, including osteoporotic compression fractures,hemangiomas, or malignancy-induced pathologic vertebral fractures. Medical therapy often is limited to pain control and immobilization. Because surgery is contraindicated frequently in patients who have osteoporotic compression fractures, and because patients who have widespread metastatic disease often are not surgical candidates, vertebroplasty may be the only practical option. In experienced hands and with appropriately selected patients, percutaneous vertebroplasty is a safe, inexpensive, and highly efficacious procedure; however, because of the potential for devastating complications, all efforts must be made to optimize patient safety.

Classification, diagnosis, and interventional radiologic management of vascular malformations.

Vascular anomalies are comprised of either hemangiomas or vascular malformations.Low-flow vascular malformations can be divided into capillary, venous, and lymphatic types and are usually present at birth, undergo pari passu growth, and produce symptoms related to mass effect or stasis. High-flow malformations are comprised pre-dominantly of arteriovenous malformations that follow a more aggressive clinical course of hyperemia, adjacent mass effect, steal phenomenon, tissue destruction, and ultimately high output failure. Ultrasound, CT, nuclear medicine, angiography, and particularly MRI have greatly enhanced diagnostic accuracy and provide detailed information for percutaneous and surgical treatment planning and an objective means of following therapeutic efficacy. Interventional radiologic percutaneous sclerotherapy for low-flow lesions and embolosclerotherapy for high-flow lesions with or without adjunctive surgical intervention have become the mainstay of therapy.

Management of central venous stent migration in a patient with a permanent inferior vena cava filter.

Stent embolization is a rare complication in the treatment of central venous stenoses in patients receiving long-term hemodialysis. The authors report a case of nitinol stent embolization into the right atrium in which the stent could not be repositioned across an indwelling permanent inferior vena cava (IVC) filter. The migrated stent was managed by advancing the stent to the superior margin of the IVC filter and then deploying a second suprarenal IVC filter to prevent repeat embolization.