Coil Packing Research Articles

Analysis of Energy Transfer in the Ignition System for High-Speed Combustion Engines

In order to produce reliable and reproducible ignition of lean fuel–air mixtures and highly stratified mixtures, it is necessary to ensure a high concentration of spark discharge energy and to provide a strong energy impulse for the triggering of chain processes of chemical decomposition of fuel molecules. For this reason, studies have been undertaken on the flow of electrical energy from the ignition system to the spark plug and on the formation of an electric discharge arc with a high concentration of thermal energy. The experimental results were obtained using an ignition coil energy test stand and a constant volume chamber with high-speed spark discharge recording capability. It was confirmed that increasing the charging time of the ignition coil from 0.5 ms to 5.0 ms increases the energy delivered to the coil from 9.5 mJ to 330 mJ. In the same range, the energy generated by the coil was recorded to range from 4.2 mJ to 70 mJ. The coil’s efficiency was found to decrease with increasing charging time from 45% up to 20.5%. Further energy losses were presented when the spark discharge energy was analyzed. In the paper, the results of investigations concerning electric discharge arc development have been presented, illustrated by a few exemplary photos, and discussed. The mathematical interpretation of the electrical energy flux in the ignition system resulting from the energy of the discharge arc has been conducted and illustrated by some functional independences and relationships.

A case of situs inversus totalis with hemosuccus pancreaticus due to intrapancreatic pseudocyst perforation of the common hepatic artery treated with a vascular stent graft.

Hemosuccus pancreaticus (HP) is characterized by gastrointestinal bleeding from the papilla of Vater via the pancreatic duct. In this report, we describe a case of HP due to arterial perforation in a pancreatic pseudocyst and discuss the computed tomography (CT) findings and efficacy of stent graft placement. A 64-year-old man with a history of heavy alcohol use, situs inversus totalis, and total gastrectomy was hospitalized with hematochezia. Enhanced CT revealed a pseudoaneurysm in the common hepatic artery (CHA) with mildly high density in the main pancreatic duct. Subsequent CT revealed an enlarged cystic lesion with inflow of contrast medium. Angiography confirmed blood flow from the CHA into the pancreatic pseudocyst, and the patient was diagnosed with HP due to intrapancreatic pseudocyst perforation of the CHA pseudoaneurysm. Coil packing into the pseudocyst failed to block the blood flow, and a covered stent graft was placed into the CHA. The patient had an uneventful clinical course. The identification of a pseudoaneurysm and a high-density area in the main pancreatic duct on enhanced CT and changes in the pancreatic cyst diameter may indicate the acute phase of HP, and stent grafting is an effective treatment for intracystic arterial perforation.

Endovascular Embolization of Aneurysmal Renal Arteriovenous Malformation

Renal arteriovenous malformations (AVM) represent an uncommon vascular condition characterized by an abnormal direct communication between an intrarenal artery and vein. Though asymptomatic in many individuals, treatment is often indicated if the AVM causes flank pain, hematuria, or medically refractory hypertension, or if there is an associated renal artery aneurysm. We present a case of a large right renal AVM with associated renal artery aneurysm and large varix which was incidentally found on magnetic resonance imaging of the spine. Endovascular and open surgical options were considered, including ex-vivo renal vascular reconstruction and nephrectomy. The patient was successfully treated with endovascular embolization of the AVM with coil packing of the arterial aneurysm and inflow artery. The patient recovered uneventfully with well-maintained renal function and blood pressure control. We review and discuss the literature on the etiology and treatment options for renal AVM.

Laboratory systems for detonation research

Decarbonizing global energy systems is among the most pertinent challenges in the climate crisis. Tightly tied to the economic prosperity of a nation and responsible for more than 75% of global emissions, decarbonization of the energy sector will require well-developed solutions. The emergence of detonation engines can reduce emissions in aviation and gas-fired power generation, with theoretical efficiencies 40% lower than conventional engines. These efficiencies have yet to be realized in practice, due to our lack of understanding of detonation propagation and its instabilities. This project aimed to develop the laboratory systems required to study detonations. To this end, a long rectangular channel was manufactured and outfitted with a gas handling system to inject a mixture, an ignition system, pressure transducers to capture the propagation characteristics, and an optical system enabling Schlieren photography. The gas handling system uses sonic nozzles, thus flow rate is a linear function of upstream line pressure. Each line contains a pressure transducer, microcontroller to process signals, LCD for pressure readout, and a regulator for adjustment of the line pressure. The ignition system uses an ignition box that steps up a 12 V supply to 400 V, an ignition coil raising the voltage to 15-40 kV, and a spark plug to ignite the mixture. Ignition, pressure transducer signal acquisition, and Schlieren photography are all synchronized using a NI-6356 DAQ with LabVIEW. The DAQs analog input ports receive readings from the pressure transducers along the channel, the timing of which and known distance between transducers allows for velocity calculations. The schlieren system utilizes the digital output channels to synchronize camera shutter with an LED driver, and parabolic mirrors, positioned to optimize schlieren imaging. The LED driver requires greater current than produced by the DAQ thus a current amplifier circuit is used to bridge the DAQ and driver.

Experimental study on the discharge characteristics of high-voltage nanosecond pulsed discharges and its effect on the ignition and combustion processes

Non-equilibrium plasma has been proven to expand ignition limits and enhance combustion. This paper uses high-voltage nanosecond pulsed discharge (NPD) to generate non-equilibrium plasma and experimentally studies the discharge characteristics at different parameters in a constant-volume combustion bomb. NPD is used to ignite the methane-air mixture, and the effects of pulse power output voltage and pulse interval (PI) on ignition and combustion processes are studied. In addition, the minimum ignition energy (MIE) at different ignition methods (Transistor coil ignition (TCI) and NPD) is also studied. The results show that the first pulse of NPD discharge has a higher breakdown voltage and discharge energy when using multi-pulse discharge. After the second pulse, the highest breakdown voltage and current tend to stabilize, and the discharge energy remains unchanged. As the PI increases, the breakdown peak voltage and the peak current increase slightly. The study on the MIE of NPD shows that at different mixture concentrations, the MIE of NPD is smaller than that of TCI, and NPD can expand the lean burn limit. An increase in initial temperature can significantly reduce MIE. In addition, when the discharge energy is near the MIE, the combustion stability begins to decrease, and the combustion cycle fluctuates wildly. When the ignition energy is increased, the stability improves, and the combustion fluctuation rate can be maintained within 5%.

Identifikasi Unjuk Kerja Mesin 4 Langkah Variasi Busi dan Koil Pengapian

The most critical component of a motorcycle's combustion process is the spark plug, which fires sparks for the ignition system. In this research, the performance of several spark plug electrode gap diameters and materials was varied to detect how much they affected engine performance, fuel consumption, and emissions. Engine testing was conducted on a 110-cc four-stroke engine. Nickel material spark plugs with a gap dimension of 0.9 mm, platinum material spark plugs with a gap dimension of 0.8 mm, iridium material spark plugs with a gap dimension of 0.7 mm, and two types of ignition coils. The test findings indicated that there is a spark plug with an appropriate gap for engine performance in the form of torque and power in the B2 configuration, which has a gap of 0.8 mm. Increasing the spark plug gap produces a loss in engine performance, but it also increases it. There is an optimal point of fuel consumption in configuration B2, where raising the spark plug gap decreases fuel consumption while increasing the spark plug gap increases fuel consumption. Exhaust emissions likewise experience an optimal point in configuration B2, when exhaust emissions rise as long as the spark plug gap is increased once more, HC and CO levels decrease with an increasing spark plug gap. To examine the study on the impact of spark plugs with electrode gaps and ignition coils on engine performance, fuel consumption, and emissions. This can provide insight into a reference technique for using spark plugs and ignition coils.

Embolization of Vessels With Irregular Lumen Using the Coil Packing Technique Between the Amplatzer Vascular Plug II Lobes.

The Amplatzer Vascular Plug(AVP) series enables precise positioning and high migration resistance, allowing embolization in short segments; however, inadequate embolization or recanalization may occasionally occur. We hypothesized that leaks may occur when AVPs are implanted in vessels with irregular lumen due to insufficient adherence to the vessel. This hypothesis was tested by experiments with a vascular model. We employed a coil packing technique between the AVP lobes to embolize internal iliac arteries with an irregular lumen. Saline was injected through the Y-shaped glass tubes of the stenotic and the smooth model (without stenotic lesion), and the amount of leakage was measured when the AVP was deployed. The feasibility and effectiveness of filling coils between the lobes of AVP II were evaluated. A total of 11 cases were retrospectively reviewed using this technique for internal iliac artery embolization prior to endovascular aortic repair. The amount of leakage was significantly higher in the presence of stenotic lesions.Insertion of a 2.2 F microcatheter from the side of the proximal lobe of AVP II and filling of coils was achieved in all 11 cases. Follow-up contrast-enhanced CT showed no recanalization, leakage, or other obvious complications. Coil packing technique around Amplatzer Vascular Plugs could be an effective method and a reliable option for arterial embolization, especially in vessels with irregular lumens.

Optical Analysis of Ignition Sparks and Inflammation Using Background-Oriented Schlieren Technique

To determine the timing of inflammation in gas and gasoline combustion engines, the point of 10% mass fraction conversion of fuel (MFB10) is commonly used. The MFB10 can be determined from the heating curve, which in turn is calculated from the in-cylinder pressure curve. However, the cylinder pressure is an indirect parameter with regard to inflammation, as it is the result of the combustion that follows the inflammation. An attempt is made to derive a new, direct parameter of inflammation based on optical measurements in order to detect inflammation more rapidly and accurately. The background-oriented Schlieren technique (BOS) in combination with high-magnification optics and a high-speed camera is used to detect local density changes coming from the particle wave around the ignition kernel of a hydrogen combustion inside a combustion chamber. Via BOS and regular high-magnification high-speed imaging, the influence of ignition coil dwell time and in-cylinder pressure on the spark phases and the inflammation itself are evaluated. As a potential direct parameter for inflammation, the size of the particle wave resulting from the expanding ignition kernel is evaluated. It was found that a higher coil energy supports a faster propagation of the particle wave at ambient pressure. At higher pressures, general combustion effects override the effect of the influence of the coil energy on the propagation speed of the particle wave. In addition, the presence of successful inflammation was found to influence the spark phases. A directly measurable parameter for ignition could be found at a basic level, which will serve as a starting point for further detailed investigations.

Experimental and numerical approach to assess the dynamic performance of an inductive ignition system

This paper envisages studying the features of a conventional inductive ignition system along with its MOSFET and IGBT-based transistorized modifications. The influence of mechanical contact breaker dynamics and ignition coil characteristics on the current and voltage waveforms of the primary and secondary circuits of these studied ignition systems are mathematically and experimentally exposed. The investigation is considered necessary prior to attempting subsequent modeling and diagnostics procedures on the current-voltage performance characteristics of conventional and transistorized ignition systems. The work has demanded the development of an experimental setup based on a basic modifiable ignition system mockup and an instrumentation system to measure and analyze the voltage-current parameters of inductive ignition systems. The paper describes the design details of such instrumentation system, presents mechanical and electrical models for contact breaker and ignition circuits, then simulated to obtain base free-run response waveforms and electrical continuity behavior of the contact. A test of frequency response of the ignition coil provided additional input to the model. An experimental test of continuity of the contact, in agreement with its model, shed light on the actual excitation of the primary coil. The work comments on a sample of the registered current and voltage waveforms in primary and secondary coil windings of the ignition system at atmospheric conditions. Comparisons of waveforms and energy for mechanical contact, MOSFET and IGBT switches are made to establish them as a reference for future tests.

PENGARUH PENGGUNAAN KOIL RACING TERHADAP PERFORMA MESIN 4 LANGKAH 125 CC

<p class="abstrak" align="left"><em>The aims of this study are : (1) To determine the effect of using racing coil on the power generated of 4 step motorcycle 125 cc, (2) To determine the effect of using racing coil on the torque generated of 4 step motorcycle 125 cc. The research method used is experimental. The data of this research was obtained by taking measurements on sample of Honda Blade 125 FI 2014 motorcycle. The independent variables were standard ignition coil and racing ignition coil. The variables were maximum shaft power dan maximum shaft torque measured using a dynamometer. The data obtained were then analyzed using quantitative descriptive techniques by describing in the form of graphs and tables. The result of the study are : (1) The use of racing ignition coil has a higher effect on the power produced. (2) The use of racing ignition coil has a lower</em> effect on the torque produced.</p>

Intermediate catheter use is associated with complete occlusion and dense packing in coil embolization of unruptured cerebral aneurysms: a propensity score matched study

BackgroundAn intermediate catheter (IMC) can improve the maneuverability and stability of the microcatheter.ObjectiveTo investigate the efficacy and safety of using an IMC in triaxial systems for coil embolization of unruptured...

Voltage modelling in ignition coil using magnetic coupling of fractional order

Voltage modelling in ignition coil using magnetic coupling of fractional order

Correlation between contrast leakage period of procedural rupture and clinical outcomes in endovascular coiling for cerebral aneurysms.

Intraprocedural rupture (IPR) is a fatal complication of endovascular coiling for cerebral aneurysms. We hypothesized that contrast leakage period may be related to poor clinical outcomes. This study aimed to retrospectively evaluate the relationship between clinical outcomes and contrast leakage period. Data from patients with cerebral aneurysms treated via endovascular coiling between January 2010 and October 2018 were retrospectively assessed. The enrolled patient's demographic data, the aneurysm related findings, endovascular treatment and IPR related findings, rescue treatment, and clinical outcome were analyzed. In total, 2,859 cerebral aneurysms were treated using endovascular coiling during the study period, with IPR occurring in 18 (0.63 %). IPR occurred during initial frame coiling (n=4), coil packing (n=5), stent deployment (n=7), ballooning (n=1), and microcatheter removal after coiling (n=1). Tear sites included the dome (n=14) and neck (n=4). All IPRs were controlled and treated with coil packing, with or without stenting. Flow arrest of the proximal balloon was not observed. Temporary focal neurological deficits developed in two patients (11.1%). At clinical follow-up, 14 patients were classified as modified Rankin Scale (mRS) 0, three as mRS 2, and one as mRS 4. The mean contrast leakage period of IPR was 11.2 min (range: 1-31 min). Cerebral aneurysms with IPR were divided into late (n=9, mean time: 17.11 min) and early (n=9, mean time: 5.22 min) control groups based on the criteria of 10 min of contrast leakage period. No significant between-group differences regarding clinical outcomes were observed after IPR (p=1). In our series, all patients with IPR were controlled with further coil packing or stenting without proximal balloon occlusion within 31 min of contrast leakage. There was no difference in clinical outcomes when the long contrast leakage period group and short contrast leakage period group were compared.

Hemodynamic analysis of coil filled patient-specific middle cerebral artery aneurysm using porous medium approach

Cerebral aneurysms are bulges of an artery, which could be life-threatening when ruptured. Depending on their size, shape, and location, they need to be managed either through clipping or an endovascular coiling intervention. When coiled, reduced hemodynamic activity enables the coil to get thrombosed and achieve flow stasis. However, some coils delivered into the aneurysm tend to prolapse into the parent vessel and cause stroke due to obstruction and embolization. The recurrence of an aneurysm after endovascular coiling is of concern in the treatment of wide necked aneurysms. The initial packing density or improper coiling of the aneurysm and its relation to recurrence remains uncertain. This study investigates the influence of reduction in coil fill volume and packing density on the aneurysm recurrence using hemodynamic parameters by analyzing its flow features. Finite element method based commercial computational fluid dynamics solver is employed for performing patient-specific simulations for the coil filled aneurysm. The present approach uses porous medium based formulation. The numerical simulations show that any reduction below the optimal coil fill volume and packing density inside the aneurysm increases the velocity magnitude, wall shear stress, time-averaged wall shear stress, and spatial gradient of wall shear stress and reduces the relative residence time. The hemodynamic parameters and flow features suggest that a reduction in the coil packing density inside the aneurysm increases the chances of aneurysm recurrence. Hence, an assessment on how to achieve optimal coil fill volume and packing density is critical in reducing the risk of aneurysm recurrence.

Abstract 180: A Prospective, Single‐Center Study Appraising Aneurysm Embolization using the Balt Optima™ Coil System (APPLY Study)

Introduction Intracranial aneurysms, both ruptured and unruptured, pose a significant risk to the general population. Cases of unruptured intracranial aneurysms (UIA) are estimated to affect roughly 3% of the general population and aneurysmal subarachnoid hemorrhage (aSAH) have an incidence of 8 to 9 people per 100,000. With the advancement of endovascular coil devices, aneurysm embolization with coiling is becoming the more preferred treatment approach compared to craniotomy with microsurgical clipping. The purpose of this study was to assess the safety and efficacy of endovascular coiling using the novel Balt Optima™ Coil System. Methods This study was an investigator‐initiated, prospective, real‐world, single‐center, post‐market study conducted in Thousand Oaks, California. Between 2020 and 2023, thirty cerebral aneurysms were treated with at least 80% utilization of the Balt Optima™ Coil System. The subjects were followed for 6 months (‐4 months/+6 months). Data points were obtained at baseline, procedure, discharge or postoperative day 7, and 6 months follow‐up (‐4 months/+6 months). Primary outcomes were functional status recorded as modified Rankin scores (mRS) and radiographic occlusion rates documented as Raymond‐Roy scores. Serious adverse events including, but not limited to, groin hematoma, periprocedural stroke, intraoperative aneurysm rupture, coil herniation requiring stent placement, and mortality were recorded. Secondary outcomes included coil packing densities, minor complications, procedure duration, disposition after hospitalization, and antithrombotic medication adjustments. Results 30 intracranial aneurysms in 29 individual subjects were included in the study and were treated by a total of 4 neurointerventionalists with at least 80% use of the Balt Optima™ Coil System. One subject had two aneurysms which were treated at two separate occasions, and the subject was consented for both aneurysms to be included in the study. 60% of aneurysms were located along the right anterior circulation and vessels involved mirrored epidemiological data in the literature. 83% of subjects were female, and 50% of aneurysms presented as ruptured. All subjects had a baseline mRS 0‐2. 83% of aneurysms were treated with utilization of an assist device as well. At 6 months follow‐up (‐4 months/+6 months), 80% of subjects had mRS 0‐2. Of the 21 patients with 6 month (‐4 months/+6 months) follow‐up imaging, 15 (71%) had complete aneurysm occlusion (Raymond‐Roy score of 1) and 6 (29%) patients had residual aneurysm neck filling (Raymond‐Roy score of 2). One subject (3%) expired during the hospitalization due to complications unrelated to the aneurysm or coil system, and one subject (3%) was lost to follow‐up. One subject (3%) developed a groin hematoma, one subject (3%) had an intraoperative rupture with no significant clinical consequence, and two subjects (7%) experienced coil herniation requiring stent placement with no clinical sequelae. No subjects (0%) had periprocedural strokes. Conclusion This study demonstrates that the Balt Optima™ Coil System is safe and effective for endovascular treatment of both unruptured and ruptured intracranial aneurysms. Additional data is needed to validate these results and compare to other coil devices on the market.

Identification of misfiring in engine 1000cc using fast fourier transform analysis

Motorized vehicles are the primary mode of transportation in the neighborhood. An automobile is one of the motorized vehicles. Because of the mixing of air and gasoline, cars may move. The spark plug plays a crucial function in combustion because it ignites the mixture of fuel and air to generate combustion. Incomplete combustion will consequently result in misfiring. Damage to the spark plug, injector, and ignition coil are just a few of the things that might lead to misfiring. Therefore, due to misfiring, research on preventive maintenance for cars is required. Utilizing the vibration approach is one option. The combustion process in this study is stimulated by changing the 1000cc engine's speed. The engine speed ranges from 900 to 3500 revolutions per minute. The accelerometer sensor is then positioned vertically and horizontally on the machine's surface. According to this study, the first form mode's frequency at 900 rpm has an amplitude of 3,433 mm/s2 and occurs at a frequency of 69 Hz. In contrast, the first mode form occurs under typical circumstances at a frequency of 99 Hz and an amplitude of 1,254 mm/s2. Furthermore, at a rotational speed of 2500 rpm, the frequency in the first shape mode is abnormal at 69 Hz with an amplitude of . In contrast, under typical circumstances, the first form mode has a frequency of 249 Hz and an amplitude of 6,721 mm/s2. A frequency of 4x rpm was discovered for the rotational speed parameters of 900 rpm and 2500 rpm. This demonstrates that a misfiring-related bearing issue exists in the piston motor system.

The safety and efficacy of double microcatheter technique in small and tiny ruptured aneurysms: A single center study.

Double microcatheter technique (dMC) can be the alternative to Single microcatheter technique (sMC) for challenging cases, but there is lack of studies comparing dMC to sMC especifically for small ruptured aneurysms. Our objective was to compare the safety and efficacy of dMC to sMC in treating small (≤5 mm) and tiny (≤3 mm) ruptured aneurysms. This study focused on 91 out of 280 patients who had ruptured aneurysms and underwent either single or double microcatheter coil embolization. These patients were treated with either single or double microcatheter coil embolization. We divided the patients into two groups based on the procedural method and evaluated clinical features and outcomes. Subgroup analyses were conducted specifically for tiny aneurysms, comparing the two methods, and within the dMC group, we also examined whether the aneurysm was tiny or not. In addition, univariate logistic regression analysis was performed to assess the impact of coil packing density. The mean values for most outcome measures in the dMC group were higher than those in the sMC group, but these differences did not reach statistical significance (coil packing density, 45.739% vs. 39.943%; procedural complication, 4.17% vs. 11.94%; recanalization, 8.3% vs. 10.45%; discharge discharge modified Rankin Scale (mRS), 1.83 vs. 1.97). The comparison between tiny aneurysms and other sizes within the dMC group did not reveal any significant differences in terms of worse outcomes or increased risk. The only factor that significantly influenced coil packing density in the univariate logistic regression analysis was the size of the aneurysm (OR 0.309, 95% CI 0.169-0.566, p=0.000). The dMC proved to be a safe and viable alternative to the sMC for treating small ruptured aneurysms in challenging cases.

A Mathematical Model for a Hybrid Ignition System

In the operation of a car's ignition system, the primary ignition coil is responsible for generating a high voltage that typically ranges from around 100V to 300V. However, this self-induced electromotive force (emf) can lead to certain negative effects such as switch breakdown, inductive noise, and secondary voltage drop. This article introduces a novel hybrid ignition system designed for a 4-cylinder engine. This innovative system is a combination of capacitive discharge ignition system (CDI) and induction discharge ignition (IDI) system. The excess electromagnetic force energy (emf) generated during the induction ignition stage will be used in the capacitive ignition. Thereby contributing to limiting the negative effects as mentioned. Forming and solving the mathematical model for the hybrid ignition system mentioned above enables us to analyze the transient responses of the primary current (i1) and primary voltage (V1). These instantaneous responses are crucial in understanding the behavior of the composite ignition circuit and calculating key parameters such as ignition energy during the inductive and capacitive ignition stages, as well as the magnitude of the maximum secondary voltage (V2m). Furthermore, the article also presents experimental results from the hybrid ignition system to complement the theoretical analysis.

Ethyl Formate as a New Sanitary Treatment for Disinfesting the Hitchhiking Insect Pest Halyomorpha halys on Imported Nonfood Agricultural Machinery

With an increase in the international trade of agricultural and non-agricultural products, there is an increase in the possibility of introducing hitchhiking insect pests such as Halyomorpha halys, which has been detected on imported vehicles and agricultural machinery. Although methyl bromide (MB) is provisionally used to control invasive pests, it is classified as a restricted chemical owing to its potential to deplete the ozone layer and pose health risks to humans in cases of inadequate ventilation, as well as concerns regarding consumer safety. Therefore, this study investigated ethyl formate’s (EF’s) efficacy against H. halys and its efficacy and sorption, as an alternative to MB, on main electronic components, including alternators, ignition coils, and motors. Fumigation with 35 and 70 g/m3 EF for 4 h at 15 °C had no damage on the main electronic components as evaluated using various operation tests. In a commercial trial, H. halys infestation was effectively controlled with 35 g/m3 EF fumigated for 4 h at 23 °C using a 30 m3 polyvinyl chloride tarpaulin fumigation chamber. After ventilation, the EF concentration decreased below the safety level within 10 min and reached the zero level within 40 min for worker safety. This novel sanitary treatment using EF fumigation on imported agricultural machinery could be an effective method without causing mechanical damage.

Hemodynamic nature of black-blood enhancement in long-term coiled cerebral aneurysms.

Vessel wall imaging (VWI) with black-blood (BB) technique can demonstrate aneurysmal enhancement preluding to growth/rupture in treatment-naive cerebral aneurysms. Interestingly, recent works showed that BB enhancement may also occur in endovascularly treated aneurysms, though its meaning is controversial. Hypothesizing a flow-related mechanism of BB enhancement, we explored its relationship with incomplete occlusion status and coil packing density at DSA. We analyzed the subjects undergoing 3T MRI between January 2017 and October 2020 for a previous aneurysmal coiling. All the MRI studies included pre- and post-contrast 3D BB sequences. The presence of intra-aneurysmal pre-contrast BB signal was assessed. BB enhancement (when present) was classified as follows: (1) enhancement at the neck, (2) intrasaccular/intra-coil enhancement, and (3) peripheral enhancement. Coil packing density and aneurysmal occlusion status (according to the modified Raymond-Roy classification, MRRC) were determined on post-treatment DSA and compared with BB findings using generalized linear mixed-effect model and ANOVA. Significant p values were <0.05. Forty-eight aneurysms from 44 patients were eligible for analysis. Pre-contrast BB signal was observed in 50% of the aneurysms and showed a relationship with baseline aneurysmal size. BB enhancement was detectable in 31 aneurysms (65%), being significantly associated with incomplete aneurysmal occlusion and reduced coil packing density at DSA. BB enhancement of coiled aneurysms is related with increasing degrees of post-coiling aneurysmal remnants and with loose coil packing density at DSA. This supports a hemodynamic interpretation of BB enhancement in long-term coiled aneurysms.