Coil Implantation Research Articles

Effectiveness and safety of detachable fibered coils as a single therapy for embolization in venous origin chronic pelvic pain.

To investigate the effectiveness and safety of endovascular treatment by embolization with detachable fibered coils of insufficient pelvic veins, as the primary cause of Venous Origin Chronic Pelvic Pain (VOCPP). This observational, retrospective study analyzes data from the PELVIC registry from 2014 to 2022. Sociodemographic, diagnostic, preoperative, intraoperative, and postoperative follow-up variables were reported. A total of 255 patients were included, with follow-up periods up to 5 years. The study's effectiveness was significant with a 60% decrease in pelvic pain at the first follow-up after treatment measured by a Visual Analogue Scale (p = 0.001). There were also decreases in the severity levels of dyspareunia (p = 0.03), dysmenorrhea (p = 0.12) and presence of Pelvic Venous Disorders symptoms in general (-43.8%; p = 0.001). No major adverse events were recorded. Only 5 patients (2%) experimented technical issues in coil implantation, all of them solved in situ. The treatment of VOCPP by embolization with detachable fibered coils has proven to be an effective and safe option for insufficient pelvic veins.

Cerebral hypoperfusion exacerbates vascular dysfunction after traumatic brain injury

Traumatic brain injuries are extremely common, and although most patients recover from their injuries many TBI patients suffer prolonged symptoms and remain at a higher risk for developing cardiovascular disease and neurodegeneration. Moreover, it remains challenging to identify predictors of poor long-term outcomes. Here, we tested the hypothesis that preexisting cerebrovascular impairment exacerbates metabolic and vascular dysfunction and leads to worse outcomes after TBI. Male mice underwent a mild surgical reduction in cerebral blood flow using a model of bilateral carotid artery stenosis (BCAS) wherein steel microcoils were implanted around the carotid arteries. Then, 30 days post coil implantation, mice underwent TBI or sham surgery. Gene expression profiles, cerebral blood flow, metabolic function, oxidative damage, vascular health and angiogenesis were assessed. Single nuclei RNA sequencing of endothelial cells isolated from mice after TBI showed differential gene expression profiles after TBI and BCAS, that were further altered when mice underwent both challenges. TBI but not BCAS increased mitochondrial oxidative metabolism. Both BCAS and TBI decreased cerebrovascular responses to repeated whisker stimulation. BCAS induced oxidative damage and inflammation in the vasculature as well as loss of vascular density, and reduced the numbers of angiogenic tip cells. Finally, intravascular protein accumulation was increased among mice that experienced both BCAS and TBI. Overall, our findings reveal that a prior vascular impairment significantly alters the profile of vascular health and function of the cerebrovasculature, and when combined with TBI may result in worsened outcomes.

EUS-guided thrombin injection and coil implantation for gastric varices: feasibility, safety, and outcomes

Gastric varices (GVs) are reported in up to 20% of patients with portal hypertension, and bleeding is often more severe and challenging than esophageal variceal bleeding. Data are limited on prophylaxis of GV bleeding or management in the acute setting, and different techniques are used. This study evaluated outcomes after EUS-guided placement of coils in combination with thrombin to manage GVs. We retrospectively reviewed all patients treated with combination EUS-guided therapy with coils and thrombin between October 2015 and February2020. Twenty patients underwent 33 procedures for GV therapy; 16 of 20 (80%) had type 1 isolated GVs and 4 patients had type 2 gastroesophageal varices. The median follow-up was 842 days (interquartile range [IQR], 483-961). Seventeen patients (85%) had underlying cirrhosis, the most common etiologies being alcohol-related liver disease and nonalcoholic steatohepatitis. The median Child-Pugh score was 6 (IQR, 5-7). In 11 patients (55%), the indication was secondary prophylaxis to prevent recurrent bleeding; in 2 of 20 patients (10%), the bleeding was acute. Technical success was achieved in 19 patients (95%). During follow-up, the obliteration of flow within the varices was achieved in 17 patients (85%). The 6-week survival rate was 100%, and 2 adverse events, recurrent bleeding at day 5 and at day 37, were reported; both recurrent bleeding events were successfully managed endoscopically. EUS-guided GV obliteration combining coil placement with thrombin, in our experience, was technically safe with good medium-term efficacy. A multicenter randomized controlled trial comparing different treatment strategies is desirable to understand options better.

Percutaneous transvenous coil embolization (PTCE) for treatment of single extrahepatic portosystemic shunt in dogs

BackgroundThere is limited information regarding percutaneous transvenous coil embolization (PTCE) for single extrahepatic portosystemic shunt (PSS). This study aimed to describe the procedure and outcome of PTCE in dogs with a single extrahepatic PSS. Forty-two privately owned dogs were included in this study. All dogs were diagnosed with extrahepatic PSS by computed tomography (CT). Preoperative CT images were used to evaluate the diameter of the PSS for coil placement. A multipurpose balloon catheter was percutaneously inserted into the PSS via the jugular vein, and transvenous retrograde portography (TRP) and measurement of blood pressure in the PSS (pPSS) were performed during balloon inflation; one or more embolization coils were implanted via the catheter.ResultsIn most cases, preoperative median fasting and postprandial serum total bile acid (TBA) concentrations were high (fasting, 86.5 μmol/L [ 3.7–250.0 μmol/L]; postprandial, 165.5 μmol/L [ 1.5–565.0 μmol/L]). CT revealed that 30 dogs had left gastrophrenic shunt; eight had left gastroazygos shunt; and one each had left gastrocaval, splenocaval, splenophrenic, and left colocaval shunt. TRP revealed that intrahepatic portal vascularity was clearly detectable in all dogs. The median values of pPSS before and during the balloon occlusion were 4.8 mmHg [2.0–13.0 mmHg] and 8.6 mmHg [5.0–18.0 mmHg], respectively. The median number and diameter of coils used were 2 coils [1 – 5 coils] and 8.0 mm [4.0 – 12.0 mm], respectively. The median times of irradiation and PTCE were 9 min [4–26 min] and 40 min [23–75 min], respectively. The median fasting and postprandial TBAs significantly decreased to 8.2 μmol/L [0.3–45.1 μmol/L, n = 38, p = 0.0028] and 19.8 μmol/L [0.3–106.7 μmol/L, n = 38, p = 0.0018], respectively, approximately 1 month after PTCE. The clinical success rate of PTCE without requirement for a second surgery was 95.2% (40/42 dogs). During revision surgery, one dog underwent surgical ligation and, in another dog, an ameroid constrictor was placed.ConclusionsPTCE was clinically effective in treating single extrahepatic PSS in dogs. Preoperative CT and TRP prior to PTCE might be clinically valuable for choosing the size of embolization coils, deciding the appropriate location of coil implantation, and estimating the number of coils to be implanted. PTCE is a promising alternative to conventional surgical procedures for single extrahepatic PSS in dogs.

Technical and clinical outcomes following EUS-guided thrombin injection and coil implantation for parastomal varices

Background and aimsBleeding from parastomal varices causes significant morbidity and mortality. Treatment options are limited, particularly in high-risk patients with significant underlying liver disease and other comorbidities. The use of...

Abstract No. 292 Balloon embolization devices deliver more rapid, complete, and lasting artery occlusion

Peripheral artery embolization procedures are performed for a variety of clinical indications including stopping life-threatening bleeding, reducing blood flow to cancerous tumors, and diverting blood away from arterial aneurysms, arteriovenous fistulas, and other vascular malformations. Typically, these procedures involve the implantation of coils or porous vascular plugs to slow blood flow and stimulate the formation of thrombus to achieve complete blood vessel occlusion. These devices often require substantial time to achieve complete occlusion, and can be susceptible to vessel recanalization, all of which can reduce the overall effectiveness of the treatment.

Azygous Vein Coil Implantation in Left Ventricular Assist Device Patients: A Hands-on Approach.

Recently, there have been reports of left ventricular assist device (LVAD) patients presenting with multiple ineffective implantable cardioverter-defibrillator (ICD) shocks. In such patients, the placement of an azygous vein coil by providing an alternative anteroposterior trajectory of the electrical shock vector can enable successful defibrillation. This review discusses a hands-on approach to azygous vein coil implantation. Additionally, we compare our tools and technique to those that have been previously described by other operators. From 2018 to 2021, eight patients were identified who underwent azygous vein coil implantation at MedStar Washington Hospital Center using a specific technique and tools. Demographic and procedural data were obtained by a retrospective review of patient charts, procedure logs, fluoroscopy, and venography performed during coil implantation. The indication for azygous vein coil implantation was ineffective ICD shocks in seven patients. The presenting rhythm was ventricular fibrillation in six (75%) cases and sustained ventricular tachycardia in two (25%) cases. Using the approach described, we were able to successfully implant an azygous vein coil in all eight (100%) patients. There were no procedure-related complications. Postimplantation, defibrillation threshold (DFT) testing was successfully performed in six of eight (75%) patients. One patient failed DFT testing despite placement of an azygous vein coil. In another patient, DFT testing was not performed because the patient was in atrial fibrillation and was not systemically anticoagulated. In conclusion, the placement of an azygous vein coil in LVAD patients with failed ICD shocks using the tools and technique described in this report is safe and highly efficacious (successful in 100% of cases).

Causes and Management of Uterine Perforation- A Review

Uterine perforation is an intrauterine problem that can occur with any therapy. It is a rare but possibly dangerous consequence of uterine manipulation, evacuation of retained products of conception or pregnancy termination (TOP), hysteroscopic treatments, and coil implantation. Injury to blood arteries or viscera, such as the bladder or the intestine, might be related. Severe bleeding or infection may ensue if not discovered at the time of surgery; nevertheless, the most majority of uterine drilling is subclinical and safe without treatment, with no substantial long-term damage. Perforation can be caused by cervical stenosis during trans-cervical operations or by a reduction in myometrial wall strength during pregnancy or menopause. Uterine abnormalities, infection, recent pregnancy, and postmenopause are all factors that raise the chance of uterine perforation. The treatment of uterine perforation is determined by the operation and the equipment employed. Admission to the hospital, intravenous antibiotics, and close supervision are required following a uterine perforation and any accompanying injuries. In this paper, we overview common causes and updated management of uterine perforation. Data was collected during a period of 6 months searching Pubmed, EPISCO, Web of science data bases to include studies with relative topics.

Proton MRS on sub-microliter volume in rat brain using implantable NMR microcoils.

The use of miniaturized NMR receiver coils is an effective approach for improving detection sensitivity in studies using MRS and MRI. By optimizing the filling factor (the fraction of the coil occupied by the sample), and by increasing the RF magnetic field produced per unit current, the sensitivity gain offered by NMR microcoils is particularly interesting when small volumes or regions of interest are investigated. For in vivo studies, millimetric or sub-millimetric microcoils can be deployed in tissues to access regions of interest located at a certain depth. In this study, the implementation and application of a tissue-implantable NMR microcoil with a detection volume of 850 nL is described. The RF magnetic field generated by the microcoil was evaluated using a finite element method simulation and experimentally determined by high spatial resolution MRI acquisitions. The performance of the microcoil in terms of spectral resolution and limit of detection was measured at 7 T in vitro and in vivo in rodent brains. These performances were compared with those of a conventional external detection coil. Proton MR spectra were acquired in the cortex of rat brain. The concentrations of main metabolites were quantified and compared with reference values from the literature. In vitro and in vivo results obtained with the implantable microcoil showed a gain in sensitivity greater than 50 compared with detection using an external coil. In vivo proton spectra of diagnostic value were obtained from brain regions of a few hundred nanoliters. The similarities between spectra obtained with the implanted microcoil and those obtained with the external NMR coil highlight the minimally invasive nature of the coil implantation procedure. These implantable microcoils represent new tools for probing tissue metabolism in very small healthy or diseased regions using MRS.

Successful right-sided azygos coil implantation for failed defibrillation thresholds using a 3D mapping system

Successful right-sided azygos coil implantation for failed defibrillation thresholds using a 3D mapping system

Low profile vascular plug for transarterial occlusion of patent ductus arteriosus in small dogs.

BackgroundMinimally invasive transcatheter occlusion using Amplatz canine duct occluder (ACDO) is the treatment of choice for dogs with left‐to‐right shunting patent ductus arteriosus (PDA). However, in small dogs the femoral artery diameter is often too small to accommodate the guiding catheter required for ACDO deployment.ObjectiveDescribe the effectiveness of transarterial implantation of Amplatzer Vascular Plug 4 (AVP‐4), the only self‐expandable nitinol mesh occlusion device which can be implanted through a 4 French diagnostic catheter, in small dogs with left‐to‐right shunting PDA.AnimalsSeven client‐owned dogs.MethodsDescriptive case series. Dogs with hemodynamically relevant left‐to‐right shunting PDA and a femoral artery diameter less than 2.0 mm measured preoperatively with ultrasonography were prospectively enrolled.ResultsAngiography after releasing the device showed complete immediate PDA closure in 5 dogs, where the manufacturers' recommendation were strictly followed (30%‐50% device oversizing of the ductal ampulla's diameter). Trivial residual flow on angiography in the 6th dog, whose device was slightly undersized, had resolved on echocardiography within 2 hours after placement. Marked device undersizing in the 7th dog resulted in severe residual shunting, which necessitated the addition of a coil. In this dog, the AVP‐4 embolized into the pulmonary artery within 2 weeks after placement.Conclusions and Clinical ImportanceTransarterial implantation of AVP‐4 is a safe, effective and technically easy procedure for PDA occlusion in small dogs and offers a valuable alternative to coil implantation. Accurate PDA measurement and device sizing is essential to prevent residual shunting, inadvertent device embolization, and protrusion of the device into the aorta.

Ineffective implantable cardioverter-defibrillator shocks among patients on continuous left ventricular assist device support: Clinical characteristics and management.

BackgroundPlacement of a left ventricular assist device (LVAD) has been described to compromise implantable cardioverter-defibrillator (ICD) defibrillation threshold (DFT). Elevated DFT will have negative consequences and increases the risk of ineffective ICD shocks, morbidity, and mortality. DFT testing is not routinely performed in clinical practice, despite this fact.ObjectiveWe describe the clinical characteristics of 7 LVAD patients who presented with multiple ineffective ICD shocks, along with the management strategy in such patients.MethodsSeven patients (5 male, mean age 52.2 ± 9 years, 85.7% nonischemic cardiomyopathy) with an ICD in situ who progressed to NYHA class IV, ACC/AHA stage D chronic systolic congestive heart failure who underwent successful LVAD implantation presented to our institution in the setting of ventricular tachyarrhythmia and ineffective ICD shocks. Six patients underwent implantation of azygos and subclavian coils with subsequent DFT testing. The remaining patient was made comfort care.ResultsFive patients had successful DFT testing with azygos (n = 4) and subclavian (n = 1) defibrillation coil implantation. One patient had unsuccessful DFT testing despite evaluation of multiple shock vectors. There were no major or minor vascular complications in any of the cases. There were no procedural-related deaths.ConclusionThis case series highlights the need for a systematic approach to management of ICDs and DFT testing in LVAD patients. The addition of new shock vectors with azygos and subclavian coil implantation may reduce DFT, shock burden, morbidity, and mortality.

Tuning of Class E Power Amplifier for Compensating the Effect of the Receiver Coil Implantation Depth on the Operation of a Wireless Transcutaneous Energy Transfer System

A method is proposed for compensating the effect of the receiver coil implantation depth on the output power of a wireless system for transcutaneous energy transfer via inductive coupling. A class E power amplifier is used in the transmitting part of the system. The proposed method is based on determining the rated values of the shunt and series capacitances used in the amplifier load circuit that would provide the required output power. The rated values of the capacitances providing the output power of 1.6 W were determined for a set of wireless energy transfer systems with the implantation depth of the receiver coil varying from 5 to 20 mm. For the selected system parameters the energy transfer efficiency was found to vary within the range of 56-93% depending on the receiver coil implantation depth.

Partial splenic embolization through endoscopic ultrasound-guided implantation of coil as a potential technique to treat portal hypertension

Partial splenic embolization through endoscopic ultrasound-guided implantation of coil as a potential technique to treat portal hypertension

A novel gold marker to aid intraoperative localisation during spinal surgery!

Methods of pre-operative level marking for spinal surgery include fiducial implants, coil implants, spinal needle implant, methylene blue and cement injection. We describe a novel gold marker used for preoperative spinal marking and report our experience.The notes and scans of patients who had gold marker for preoperative spinal marking over the period from June 2016 to November 2018 were analysed.20 patients had preoperative spinal marking using the gold marker. The accuracy was 100% and there were no complications. Compared to injecting cement, we save over £700 per patient!

MRI-Induced Heating of Coils for Microscopic Magnetic Stimulation at 1.5 Tesla: An Initial Study.

PurposeDeep brain stimulation (DBS) has proved to be effective in the treatment of movement disorders. However, the direct contact between the metal contacts of the DBS electrode and the brain can cause RF heating in magnetic resonance imaging (MRI) scanning, due to an increase of local specific absorption rate (SAR). Recently, micro coils (μMS) have demonstrated excitation of neuronal tissue through the electromagnetic induction both in vitro and in vivo experiments. In contrast to electrical stimulation, in μMS, there is no direct contact between the metal and the biological tissue.MethodsWe compared the heating of a μMS coil with a control case of a metal wire. The heating was induced by RF fields in a 1.5 T MRI head birdcage coil (often used for imaging patients with implants) at 64 MHz, and normalized results to 3.2 W/kg whole head average SAR.ResultsThe μMS coil or wire implants were placed inside an anatomically accurate head saline-gel filled phantom inserted in the RF coil, and we observed approximately 1°C initial temperature rise at the μMS coil, while the wire exhibited a 10°C temperature rise in the proximity of the exposed end. The numerical simulations showed a 32-times increase of local SAR induced at the tips of the metal wire compared to the μMS.ConclusionIn this work, we show with measurements and electromagnetic numerical simulations that the RF-induced increase in local SAR and induced heating during MRI scanning can be greatly reduced by using magnetic stimulation with the proposed μMS technology.

Clinical and histopathologic characteristics of patients undergoing surgical excision with Essure coils: Longitudinal experience at a women's specialty hospital

The introduction of the Essure (Bayer AG, Leverkusen, Germany) device made possible a less invasive approach for patients desiring sterilization. Following FDA approval in 2002, problems were reported in some patients with these devices including most commonly pain. Labeling changes were mandated in 2016, and as of late 2018, the devices are no longer being sold in the United States. A comprehensive description of Pathologic findings in patients with these devices has not been reported. This study characterizes pathologic findings in patients undergoing surgery who had Essure in place, regardless of the indication for surgery. 137 cases were found, 126 of which had submitted tissue, 121 of which had fallopian tube(s) submitted. Duration for coils being in place was available for 104/137 patients (mean 48 months; median 43 months, range 0–166 months). Cases ranged from 2009 to 19, with a peak in cases noted in 2016. A chief complaint relating to the phrase “pelvic pain” was the most common, noted in 72/137 cases. Obliteration, defined as loss of the fallopian tube epithelium with filling of the lumen with fibrotic material, was noted in 33/121 cases. Inflammation was noted in 59/126 cases, 31/59 showed with giant cells, chronic inflammation (lymphocytes and/or plasma cells) in 37/59 cases, and acute inflammation 19/59 cases, with 14/19 showing eosinophils. Acute inflammation was noted in those with a shorter duration of coil implantation, while chronic inflammation, including giant cells, were noted across the span. This study has expanded knowledge of patients with removal of Essure coil devices.

Experience of implantation of flow-diverter in the acute period of aneurismatic intracranial hemorrhage

In the period from 2013 to 2019 at the Scientific and Practical Center for Endovascular Neuroradiology of the National Academy of Medical Sciences of Ukraine, implantation of flow-diverter in the acute period of aneurysmal intracranial hemorrhage was performed in six patients (4 (66.7 %) men and 2 (33.3 %) women. The average age was 50 years). Hemorrhage was diagnosed using multispiral computed tomography, aneurysm was verified using cerebral subtraction angiography according to Seldinger. In 3 cases the aneurysm was located on the internal carotid artery, in 2 cases – on V4-segment of the vertebral artery, in1 case – on A1-segment of the anterior cerebral artery. Five patients received a loading dose of double antiplatelet therapy before implantation of a flow-diverter (300 mg clopidogrel and 300 mg acetylsalicylic acid). One patient received dual antiplatelet therapy (75 mg clopidogrel and 75 mg acetylsalicylic acid) in five days before stent implantation. All patients after implantation of a flow-diverter received double antiplatelet therapy in a standard dose (75 mg clopidogrel and 75 mg acetylsalicylic acid). In five cases a FRED (Microvention - Terumo) flow-diverter was used and in one case – Pipeline (Medtronic). The diameter and length of the stent depended on the angioantomy of the aneurysm and the bearing artery. In two cases the implantation of a flow-diverter was accompanied by the implantation of micro coils into the cavity of the aneurysm, in four cases – as a single endovascular treatment technique. There were no complications in the early or late postoperative period. At the time of discharge on the Glasgow modified exit scale (GOSE) five patients had more than 5 points, one patient died (1 point) for reasons not related to the underlying disease. A control examination in the period from 6 to 12 month after implantation passed three patients, in all cases of aneurysm from the blood circulation is totally excluded.

5-Year Survival after Endobronchial Coil Implantation: Secondary Analysis of the First Randomised Controlled Trial, RESET

Background: Lung volume reduction surgery is a proven treatment for emphysematous patients with hyperinflation, but the precarious health of candidates has prompted development of less invasive approaches. Bronchoscopic implanted endobronchial coils, shape-memory nitinol filaments, shrink emphysematous lung tissue to restore elastic recoil and to tether airways to maintain patency. Studies have demonstrated an acceptable safety profile and improvements in lung function, exercise capacity, and quality of life out to 3 years. Volume reduction is key. However, data for longer-term survival are limited. Objective: The aim of this study was to establish the 5-year overall and transplant-free survivals of subjects whose procedure in the first randomized controlled trial, RESET, achieved clinically meaningful reduction in residual volume (RV). Methods: Patients and their primary care doctors were contacted to confirm vital status and history of additional interventions. Death certificates were acquired via the General Registry Office. Survival time was calculated for responders achieving a reduction of ≥10% in RV compared to non-responders. Results: 39 patients completed the planned bilateral sequential treatments. Six patients received unilateral implants. At 5 years, 22 patients had died. The overall survivals at 1, 2, 3, 4 and 5 years were 88.9, 88.9, 77.8, 64.4 and 50.6%, respectively. Two patients underwent lung transplantation at 52 and 59 months and were alive at 5 years. The transplant-free (TF) survivals at 1, 2, 3, 4 and 5 years were 88.9, 88.9, 77.8, 64.4 and 46.7%, respectively. Volume reduction responders (n = 18) at 3 months had a 5-year TF survival of 66.7% compared to 36.4% for non-responders (n = 22; p = 0.07). Higher baseline inspiratory capacity (HR 0.13, 95% CI 0.02–0.73; p = 0.02) and partial pressure of oxygen (pO₂) (HR 0.57, 95% CI 0.38–0.86; p < 0.01) values were predictive of survival for the entire cohort and were not influenced by age. Conclusions: Endobronchial coil implantation appears to confer a 5-year survival advantage for those who achieved a 10% reduction in RV at 3 months. Ongoing trials are designed to clarify the mechanisms of action of coils and to refine patient selection.

Aneurysm wall cellularity affects healing after coil embolization: assessment in a rat saccular aneurysm model

Background and purposeDespite significant technical advances, recanalization rates after endovascular therapy of ruptured intracranial aneurysms (IAs) remain a clinical challenge. A histopathological hallmark of ruptured human IA walls is mural...