Cartilage and bone neoformation in rabbit carotid bifurcation aneurysms after endovascular coil embolization

Directory of Open Access Journals (Sweden)

H Plenk

2008-11-01

Full Text Available Occurrence and histomorphology of cartilage and bone neoformations was retrospectively evaluated in rabbit experimental aneurysms after endovascular coil embolization. During product development, 115 carotid bifurcation aneurysms were treated with hydrogel-containing devices (HydroCoil®, n=77; HydroSoft®, n=28; prototype Hydrogel-only, n=10; MicroVentionTerumo, Aliso Viejo, CA. Additional 29 aneurysms were treated with standard (n=22 or with degradable polymer-covered (n=7 platinum coils. After 4 to 52 weeks, the retrieved aneurysms were methylmethacrylate embedded, and ground sections were surface-stained with Rapid Bone Stain and Giemsa solution. Cartilage and/or bone tissue was assessed by light microscopy; respective tissue areas in the aneurysms were determined by computerized histomorphometry. Cartilage neoformation was observed from 26 to 52 weeks. Single chondrocytes to hyaline or fibrous cartilage areas, occupying up to 29% of the aneurysm cavity, were found in 6 aneurysms, treated with HydroCoil (n=4, Hydrogel-only (n=1, and resorbable polymer (n=1 devices. Chondral ossification associated cartilage neoformation in 2 of these 4 HydroCoil-treated aneurysms. Membranous woven and lamellar bone ossicles were observed from 13 to 52 weeks in 7 aneurysms, treated with HydroCoil (n=3 and platinum coil (n=4 devices. Altogether, cartilage and/or bone neoformation was observed in 13 (9% of 144 rabbit bifurcation aneurysms treated with various embolic devices. Incidence was low until 26 weeks, but increased at 52 weeks in both, HydroCoil and standard platinum coil treated aneurysms. As the neoformations were predominantly located in proximity to the aneurysm neck, they could be related to the long-term mechanobiology of cell differentiation during fibrovascular healing of blood flow-exposed embolized aneurysms.

Adaptive grid generation in a patient-specific cerebral aneurysm

Science.gov (United States)

Hodis, Simona; Kallmes, David F.; Dragomir-Daescu, Dan

2013-11-01

computational time for patient-specific hemodynamics simulations, which are used to help assess the likelihood of aneurysm rupture using CFD calculated flow patterns.

Patient- and Aneurysm-Specific Risk Factors for Intracranial Aneurysm Growth : A Systematic Review and Meta-Analysis

NARCIS (Netherlands)

Backes, Daan; Rinkel, Gabriel J E; Laban, Kamil G.; Algra, Ale; Vergouwen, Mervyn D I

2016-01-01

BACKGROUND AND PURPOSE—: Follow-up imaging is often performed in intracranial aneurysms that are not treated. We performed a systematic review and meta-analysis on patient- and aneurysm-specific risk factors for aneurysm growth. METHODS—: We searched EMBASE and MEDLINE for cohort studies describing

Patient specific 3D printed phantom for IMRT quality assurance

International Nuclear Information System (INIS)

Ehler, Eric D; Higgins, Patrick D; Dusenbery, Kathryn E; Barney, Brett M

2014-01-01

The purpose of this study was to test the feasibility of a patient specific phantom for patient specific dosimetric verification. Using the head and neck region of an anthropomorphic phantom as a substitute for an actual patient, a soft-tissue equivalent model was constructed with the use of a 3D printer. Calculated and measured dose in the anthropomorphic phantom and the 3D printed phantom was compared for a parallel-opposed head and neck field geometry to establish tissue equivalence. A nine-field IMRT plan was constructed and dose verification measurements were performed for the 3D printed phantom as well as traditional standard phantoms. The maximum difference in calculated dose was 1.8% for the parallel-opposed configuration. Passing rates of various dosimetric parameters were compared for the IMRT plan measurements; the 3D printed phantom results showed greater disagreement at superficial depths than other methods. A custom phantom was created using a 3D printer. It was determined that the use of patient specific phantoms to perform dosimetric verification and estimate the dose in the patient is feasible. In addition, end-to-end testing on a per-patient basis was possible with the 3D printed phantom. Further refinement of the phantom construction process is needed for routine use. (paper)

Angle change of the parent arteries after stent-assisted coil embolization of wide-necked intracranial bifurcation aneurysms

International Nuclear Information System (INIS)

Cho, W.-S.; Kang, H.-S.; Kim, J.E.; Kwon, O.-K.; Oh, C.W.; Cho, Y.D.; Han, M.H.

2014-01-01

Aim: To investigate the angle changes of the parent arteries after stent-assisted coil embolization of wide-necked intracranial bifurcation aneurysms. Materials and methods: The adjacent parent arterial angles before and after stent-assisted coil embolization were measured in 38 patients with aneurysms of the anterior communicating artery (ACoAA) and 41 patients with bifurcation aneurysms of the middle cerebral artery (MCABA). Variables were analysed in relation to the angle changes. Results: Vascular angles of the parent arteries significantly increased by 27.8° (±18.5°) immediately after stent-assisted coil embolization in 79 cases (p < 0.001), with 25.7° (±14.8°) in ACoAA and 29.7° (±21.4°) in MCABA, respectively. In 51 (64.6%) cases with follow-up angiography (mean interval 13.5 ± 4.1 months), vascular angles increased by 27.2° (±17.1°) immediately after treatment and further increased by 20.7° (±14.3°) at the last follow-up (all p < 0.001). More acute pre-stent angles of the parent arteries correlated with greater post-stent angle changes (p = 0.006). Younger age tended to be inversely related to post-stent angle changes (p = 0.091). Conclusion: Stent placement during coil embolization induced significant changes in the aneurysm–parent artery relationship. Further study is needed to elicit the association between angle change of the parent arteries and aneurysmal stability after coil embolization

A comparative study on patient specific absolute dosimetry using slab phantom, acrylic body phantom and goat head phantom

Directory of Open Access Journals (Sweden)

Om Prakash Gurjar

2015-01-01

Full Text Available Purpose: To compare the results of patient specific absolute dosimetry using slab phantom, acrylic body phantom and goat head phantom. Methods: Fifteen intensity modulated radiotherapy (IMRT plans already planned on treatment planning system (TPS for head-and-neck cancer patients were exported on all three kinds of phantoms viz. slab phantom, acrylic body phantom and goat head phantom, and dose was calculated using anisotropic analytic algorithm (AAA. All the gantry angles were set to zero in case of slab phantom while set to as it is in actual plan in case of other two phantoms. All the plans were delivered by linear accelerator (LA and dose for each plan was measured by 0.13 cc ion chamber. The percentage (% variations between planned and measured doses were calculated and analyzed. Results: The mean % variations between planned and measured doses of all IMRT quality assurance (QA plans were as 0.65 (Standard deviation (SD: 0.38 with confidence limit (CL 1.39, 1.16 (SD: 0.61 with CL 2.36 and 2.40 (SD: 0.86 with CL 4.09 for slab phantom, acrylic head phantom and goat head phantom respectively. Conclusion: Higher dose variations found in case of real tissue phantom compare to results in case of slab and acrylic body phantoms. The algorithm AAA does not calculate doses in heterogeneous medium as accurate as it calculates in homogeneous medium. Therefore the patient specific absolute dosimetry should be done using heterogeneous phantom mimicking density wise as well as design wise to the actual human body.  

Safety and efficacy of aneurysm treatment with WEB

DEFF Research Database (Denmark)

Pierot, Laurent; Costalat, Vincent; Moret, Jacques

2016-01-01

OBJECT WEB is an innovative intrasaccular treatment for intracranial aneurysms. Preliminary series have shown good safety and efficacy. The WEB Clinical Assessment of Intrasaccular Aneurysm Therapy (WEBCAST) trial is a prospective European trial evaluating the safety and efficacy of WEB in wide......-neck bifurcation aneurysms. METHODS Patients with wide-neck bifurcation aneurysms for which WEB treatment was indicated were included in this multicentergood clinical practices study. Clinical data including adverse events and clinical status at 1 and 6 months were collected and independently analyzed by a medical....... RESULTS Ten European neurointerventional centers enrolled 51 patients with 51 aneurysms. Treatment with WEB was achieved in 48 of 51 aneurysms (94.1%). Adjunctive implants (coils/stents) were used in 4 of 48 aneurysms (8.3%). Thromboembolic events were observed in 9 of 51 patients (17.6%), resulting...

The effect of inlet waveforms on computational hemodynamics of patient-specific intracranial aneurysms.

Science.gov (United States)

Xiang, J; Siddiqui, A H; Meng, H

2014-12-18

Due to the lack of patient-specific inlet flow waveform measurements, most computational fluid dynamics (CFD) simulations of intracranial aneurysms usually employ waveforms that are not patient-specific as inlet boundary conditions for the computational model. The current study examined how this assumption affects the predicted hemodynamics in patient-specific aneurysm geometries. We examined wall shear stress (WSS) and oscillatory shear index (OSI), the two most widely studied hemodynamic quantities that have been shown to predict aneurysm rupture, as well as maximal WSS (MWSS), energy loss (EL) and pressure loss coefficient (PLc). Sixteen pulsatile CFD simulations were carried out on four typical saccular aneurysms using 4 different waveforms and an identical inflow rate as inlet boundary conditions. Our results demonstrated that under the same mean inflow rate, different waveforms produced almost identical WSS distributions and WSS magnitudes, similar OSI distributions but drastically different OSI magnitudes. The OSI magnitude is correlated with the pulsatility index of the waveform. Furthermore, there is a linear relationship between aneurysm-averaged OSI values calculated from one waveform and those calculated from another waveform. In addition, different waveforms produced similar MWSS, EL and PLc in each aneurysm. In conclusion, inlet waveform has minimal effects on WSS, OSI distribution, MWSS, EL and PLc and a strong effect on OSI magnitude, but aneurysm-averaged OSI from different waveforms has a strong linear correlation with each other across different aneurysms, indicating that for the same aneurysm cohort, different waveforms can consistently stratify (rank) OSI of aneurysms. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Effect of Inlet Waveforms on Computational Hemodynamics of Patient-Specific Intracranial Aneurysms

OpenAIRE

Xiang, J.; Siddiqui, A.H.; Meng, H.

2014-01-01

Due to the lack of patient-specific inlet flow waveform measurements, most computational fluid dynamics (CFD) simulations of intracranial aneurysms usually employ waveforms that are not patient-specific as inlet boundary conditions for the computational model. The current study examined how this assumption affects the predicted hemodynamics in patient-specific aneurysm geometries. We examined wall shear stress (WSS) and oscillatory shear index (OSI), the two most widely studied hemodynamic qu...

Turnover in intracranial aneurysm phantoms: its relation to neck size

International Nuclear Information System (INIS)

Chung, Tae Sub; Lee, Young Jun; Rhim, Yoon Chul

2003-01-01

To evaluate the physiologic background of aneurysms poorly visualized during 3D-TOF MRA, contrast-enhanced MRA (CEMRA) and DSA due to hemodynamic isolation. Using handmade elastic silicon phantoms to represent terminal basilar tip aneurysms, 3D-TOF MRA, CEMRA and DSA were used to determine blood turnover. Aneurysmal neck size was 2 mm and 10 mm, and the use of a pulsatile pump also helped recreate human physiologic parameters. We compared the results with those of computational fluid dynamics. DSA images of the narrow-necked aneurysm showed that a small volume of contrast medium washed into it during the systolic phase. As the width of its neck increased, the turnover volume of fragments of contrast bolus also increased. At CEMRA, the broad-necked aneurysm was visualized as the main bolus of Gd-DTPA passed through it, and at delayed CEMRA, the narrow-necked aneurysm was visualized faintly after the passage of bolus Gd-DTPA. The results correlated closely with those of 3D-TOF MRA and computational fluid dynamics. The visualization of intracranial aneurysms at 3D-TOF MRA, CEMRA and DSA was greatly dependent upon blood turnover, which varied according to aneurysmal neck size. A narrow-necked aneurysm might be missed at 3D-TOF MRA, CEMRA and DSA due to hemodynamic isolation

Patient-specific cardiac phantom for clinical training and preprocedure surgical planning.

Science.gov (United States)

Laing, Justin; Moore, John; Vassallo, Reid; Bainbridge, Daniel; Drangova, Maria; Peters, Terry

2018-04-01

Minimally invasive mitral valve repair procedures including MitraClip ® are becoming increasingly common. For cases of complex or diseased anatomy, clinicians may benefit from using a patient-specific cardiac phantom for training, surgical planning, and the validation of devices or techniques. An imaging compatible cardiac phantom was developed to simulate a MitraClip ® procedure. The phantom contained a patient-specific cardiac model manufactured using tissue mimicking materials. To evaluate accuracy, the patient-specific model was imaged using computed tomography (CT), segmented, and the resulting point cloud dataset was compared using absolute distance to the original patient data. The result, when comparing the molded model point cloud to the original dataset, resulted in a maximum Euclidean distance error of 7.7 mm, an average error of 0.98 mm, and a standard deviation of 0.91 mm. The phantom was validated using a MitraClip ® device to ensure anatomical features and tools are identifiable under image guidance. Patient-specific cardiac phantoms may allow for surgical complications to be accounted for preoperative planning. The information gained by clinicians involved in planning and performing the procedure should lead to shorter procedural times and better outcomes for patients.

Endovascular stenting for treatment of complex intracranial aneurysms: preliminary outcome

International Nuclear Information System (INIS)

Huang Qinghai; Liu Jianmin; Xu Yi; Hong Bo; Zhao Wenyuan; Zhou Xiaoping

2004-01-01

Objective: To summarize the technique and efficiency of combined endovascular stenting and Guglielmi detachable coils (GDC) packing for the treatment of intracranial wide-necked bifurcation aneurysms and recanalized aneurysms. Methods: The coronary stents were implanted across the necks of 5 intracranial wide-necked aneurysms (two at bifurcation of ICA, one at basilar artery and two recanalized PcoA aneurysms). The porous stents covered the ostia of vital side branches and perforating vessels in three cases. Microcatheters were introduced into the aneurysmal sac through the stent mesh and then followed by GDCs embolizing the aneurysms. Results: The stents were deployed in parent artery in all cases. Total occlusion was obtained in 4 cases, while more than 90% in one case with patency of the parent arteries and vital perforating arteries. Follow-up angiography performed in all patients 3-6 months later revealed no intrastent stenosis. All the patients recovered well except III nerve palsy in one patient which diminished 3 months later. Conclusion: Endovaseular therapy combined stent implantation and microcoil placement maybe a valid alteration for the treatment of wide-necked bifurcation aneurysms and recanalized aneurysms, which shows promise clinical application in the future. The ostia of vital side branches covered with stents showed no effect on hemodynamics. (authors)

Experimental study on representation of flow on the bifurcated carotid arterial phantoms using magnetic resonance angiography

International Nuclear Information System (INIS)

Chung, Tae Sub; Rhim, Yoon Chul; Kim, Kyung Oh; Suh, Sang Ho; Jin, En Hao

1995-01-01

A common finding of carotid artery on magnetic resonance angiograms(MRAs) is a signal dropout along the posterior wall of carotid bulb due to reverse flow. The purpose of this study is to evaluate variable flow patterns on bifurcated carotid arterial phantoms using steady-state flow. We designed phantoms of a bifurcated carotid artery with acrylic materials. Flow patterns were evaluated with axial and coronal imaging of MRA(2D-TOF, 3D-TOF), color Doppler imaging, and computational fluid dynamics (CFD) within the phantoms constructed of an automated closed-type circulatory system filled with 4% sugar solution. These findings were compared with findings obtained from normal volunteers. Axial 3D-TOF MRA images exhibited closer resemblance to the contour of the inner wall of phantoms when compared to coronal 2D-TOF MRA imaging. However, 2D-TOF MRA showed good contrast difference of signal intensities between forward flow area and reverse flow area. Dark zones with reduced signal intensities due to reversed flow were separated from the outer wall of the internal and external carotid arteries by a thin layer of forward flow along the wall on the source slice image of MRA. The general hemodynamics of the phantoms on MRA were identical to hemodynamics on color Doppler imaging and CFD. The results obtained with the phantoms matched the findings on normal volunteers. Although representations of bifurcated carotid arterial phantoms on axial 3D-TOF MRA were excellent if ideally designed, the zone of reversed flow could be a significant factor in creating distorted image when the zone of reversed flow contacted directly with curved or deformed arterial wall

Phantom-based experimental validation of computational fluid dynamics simulations on cerebral aneurysms

Energy Technology Data Exchange (ETDEWEB)

Sun Qi; Groth, Alexandra; Bertram, Matthias; Waechter, Irina; Bruijns, Tom; Hermans, Roel; Aach, Til [Philips Research Europe, Weisshausstrasse 2, 52066 Aachen (Germany) and Institute of Imaging and Computer Vision, RWTH Aachen University, Sommerfeldstrasse 24, 52074 Aachen (Germany); Philips Research Europe, Weisshausstrasse 2, 52066 Aachen (Germany); Philips Healthcare, X-Ray Pre-Development, Veenpluis 4-6, 5684PC Best (Netherlands); Institute of Imaging and Computer Vision, RWTH Aachen University, Sommerfeldstrasse 24, 52074 Aachen (Germany)

2010-09-15

Purpose: Recently, image-based computational fluid dynamics (CFD) simulation has been applied to investigate the hemodynamics inside human cerebral aneurysms. The knowledge of the computed three-dimensional flow fields is used for clinical risk assessment and treatment decision making. However, the reliability of the application specific CFD results has not been thoroughly validated yet. Methods: In this work, by exploiting a phantom aneurysm model, the authors therefore aim to prove the reliability of the CFD results obtained from simulations with sufficiently accurate input boundary conditions. To confirm the correlation between the CFD results and the reality, virtual angiograms are generated by the simulation pipeline and are quantitatively compared to the experimentally acquired angiograms. In addition, a parametric study has been carried out to systematically investigate the influence of the input parameters associated with the current measuring techniques on the flow patterns. Results: Qualitative and quantitative evaluations demonstrate good agreement between the simulated and the real flow dynamics. Discrepancies of less than 15% are found for the relative root mean square errors of time intensity curve comparisons from each selected characteristic position. The investigated input parameters show different influences on the simulation results, indicating the desired accuracy in the measurements. Conclusions: This study provides a comprehensive validation method of CFD simulation for reproducing the real flow field in the cerebral aneurysm phantom under well controlled conditions. The reliability of the CFD is well confirmed. Through the parametric study, it is possible to assess the degree of validity of the associated CFD model based on the parameter values and their estimated accuracy range.

Phantom-based experimental validation of computational fluid dynamics simulations on cerebral aneurysms

International Nuclear Information System (INIS)

Sun Qi; Groth, Alexandra; Bertram, Matthias; Waechter, Irina; Bruijns, Tom; Hermans, Roel; Aach, Til

2010-01-01

Purpose: Recently, image-based computational fluid dynamics (CFD) simulation has been applied to investigate the hemodynamics inside human cerebral aneurysms. The knowledge of the computed three-dimensional flow fields is used for clinical risk assessment and treatment decision making. However, the reliability of the application specific CFD results has not been thoroughly validated yet. Methods: In this work, by exploiting a phantom aneurysm model, the authors therefore aim to prove the reliability of the CFD results obtained from simulations with sufficiently accurate input boundary conditions. To confirm the correlation between the CFD results and the reality, virtual angiograms are generated by the simulation pipeline and are quantitatively compared to the experimentally acquired angiograms. In addition, a parametric study has been carried out to systematically investigate the influence of the input parameters associated with the current measuring techniques on the flow patterns. Results: Qualitative and quantitative evaluations demonstrate good agreement between the simulated and the real flow dynamics. Discrepancies of less than 15% are found for the relative root mean square errors of time intensity curve comparisons from each selected characteristic position. The investigated input parameters show different influences on the simulation results, indicating the desired accuracy in the measurements. Conclusions: This study provides a comprehensive validation method of CFD simulation for reproducing the real flow field in the cerebral aneurysm phantom under well controlled conditions. The reliability of the CFD is well confirmed. Through the parametric study, it is possible to assess the degree of validity of the associated CFD model based on the parameter values and their estimated accuracy range.

Development of a patient-specific two-compartment anthropomorphic breast phantom

International Nuclear Information System (INIS)

Prionas, Nicolas D; Burkett, George W; McKenney, Sarah E; Chen, Lin; Boone, John M; Stern, Robin L

2012-01-01

The purpose of this paper is to develop a technique for the construction of a two-compartment anthropomorphic breast phantom specific to an individual patient's pendant breast anatomy. Three-dimensional breast images were acquired on a prototype dedicated breast computed tomography (bCT) scanner as part of an ongoing IRB-approved clinical trial of bCT. The images from the breast of a patient were segmented into adipose and glandular tissue regions and divided into 1.59 mm thick breast sections to correspond to the thickness of polyethylene stock. A computer-controlled water-jet cutting machine was used to cut the outer breast edge and the internal regions corresponding to glandular tissue from the polyethylene. The stack of polyethylene breast segments was encased in a thermoplastic ‘skin’ and filled with water. Water-filled spaces modeled glandular tissue structures and the surrounding polyethylene modeled the adipose tissue compartment. Utility of the phantom was demonstrated by inserting 200 µm microcalcifications as well as by measuring point dose deposition during bCT scanning. Affine registration of the original patient images with bCT images of the phantom showed similar tissue distribution. Linear profiles through the registered images demonstrated a mean coefficient of determination (r 2 ) between grayscale profiles of 0.881. The exponent of the power law describing the anatomical noise power spectrum was identical in the coronal images of the patient's breast and the phantom. Microcalcifications were visualized in the phantom at bCT scanning. The real-time air kerma rate was measured during bCT scanning and fluctuated with breast anatomy. On average, point dose deposition was 7.1% greater than the mean glandular dose. A technique to generate a two-compartment anthropomorphic breast phantom from bCT images has been demonstrated. The phantom is the first, to our knowledge, to accurately model the uncompressed pendant breast and the glandular tissue

Endovascular treatment of basilar and ICA termination aneurysms: effects of the use of HydroCoils on treatment stability in a subgroup of patients prone to a higher recurrence rate

International Nuclear Information System (INIS)

Geyik, Serdar; Yavuz, Kivilcim; Cekirge, Saruhan; Saatci, Isil

2007-01-01

The aim of this study was to evaluate the stability of occlusion of terminal bifurcation aneurysms after embolization with hydrogel-coated coils. Of 35 bifurcation aneurysms, 34 were treated with hydrogel-coated coils in combination with platinum coils, and 1 was treated with hydrogel-coated coils only. Aneurysms were located at the basilar tip in 17 patients, and the internal carotid artery (ICA) bifurcation in 18 patients. The patient population consisted of 20 women and 15 men with ages ranging from 21 to 65 years. The aneurysm was found in 16 patients on presentation for subarachnoid hemorrhage, and in 19 patients the finding was incidental. Of the 35 aneurysms, 25 were small, 9 were large and 1 was giant. The giant aneurysm was located at the basilar tip and showed partial thrombosis. All except two basilar tip aneurysms were treated with balloon assistance. The remaining two basilar tip aneurysms were embolized with the assistance of an aneurysmal neck bridge device. The mean percentage occluded aneurysm volume for all devices was in the range 34-100%. Follow-up angiograms were obtained at 1 year in 6 patients, 2 years in 11 patients, and 3 years in 18 patients. Angiograms obtained immediately after embolization demonstrated a Raymond class 1 occlusion in 29 patients (82.9%) and a Raymond class 2 occlusion in 6 patients (17.1%). In four of these six patients follow-up angiograms demonstrated regrowth with resultant Raymond class 3 occlusion. In the other two patients, Raymond class 2 occlusion remained stable on follow-up angiograms. In patients who had a Raymond class 1 occlusion on the angiogram obtained immediately after embolization, no regrowth was seen on the follow-up angiograms. The overall recanalization rate was 11.4% (three large, one giant) at 6 months. Retreatment was not considered in three of these patients and they were to be followed; the other patient was retreated. Our initial procedural data demonstrate that higher volumetric occlusion was

Endovascular treatment of basilar and ICA termination aneurysms: effects of the use of HydroCoils on treatment stability in a subgroup of patients prone to a higher recurrence rate

Energy Technology Data Exchange (ETDEWEB)

Geyik, Serdar; Yavuz, Kivilcim; Cekirge, Saruhan; Saatci, Isil [Hacettepe University Hospital, Interventional Neuroradiology Unit, Radiology Department, Ankara (Turkey)

2007-12-15

The aim of this study was to evaluate the stability of occlusion of terminal bifurcation aneurysms after embolization with hydrogel-coated coils. Of 35 bifurcation aneurysms, 34 were treated with hydrogel-coated coils in combination with platinum coils, and 1 was treated with hydrogel-coated coils only. Aneurysms were located at the basilar tip in 17 patients, and the internal carotid artery (ICA) bifurcation in 18 patients. The patient population consisted of 20 women and 15 men with ages ranging from 21 to 65 years. The aneurysm was found in 16 patients on presentation for subarachnoid hemorrhage, and in 19 patients the finding was incidental. Of the 35 aneurysms, 25 were small, 9 were large and 1 was giant. The giant aneurysm was located at the basilar tip and showed partial thrombosis. All except two basilar tip aneurysms were treated with balloon assistance. The remaining two basilar tip aneurysms were embolized with the assistance of an aneurysmal neck bridge device. The mean percentage occluded aneurysm volume for all devices was in the range 34-100%. Follow-up angiograms were obtained at 1 year in 6 patients, 2 years in 11 patients, and 3 years in 18 patients. Angiograms obtained immediately after embolization demonstrated a Raymond class 1 occlusion in 29 patients (82.9%) and a Raymond class 2 occlusion in 6 patients (17.1%). In four of these six patients follow-up angiograms demonstrated regrowth with resultant Raymond class 3 occlusion. In the other two patients, Raymond class 2 occlusion remained stable on follow-up angiograms. In patients who had a Raymond class 1 occlusion on the angiogram obtained immediately after embolization, no regrowth was seen on the follow-up angiograms. The overall recanalization rate was 11.4% (three large, one giant) at 6 months. Retreatment was not considered in three of these patients and they were to be followed; the other patient was retreated. Our initial procedural data demonstrate that higher volumetric occlusion was

Treatment planning for image-guided neuro-vascular interventions using patient-specific 3D printed phantoms

Science.gov (United States)

Russ, M.; O'Hara, R.; Setlur Nagesh, S. V.; Mokin, M.; Jimenez, C.; Siddiqui, A.; Bednarek, D.; Rudin, S.; Ionita, C.

2015-03-01

Minimally invasive endovascular image-guided interventions (EIGIs) are the preferred procedures for treatment of a wide range of vascular disorders. Despite benefits including reduced trauma and recovery time, EIGIs have their own challenges. Remote catheter actuation and challenging anatomical morphology may lead to erroneous endovascular device selections, delays or even complications such as vessel injury. EIGI planning using 3D phantoms would allow interventionists to become familiarized with the patient vessel anatomy by first performing the planned treatment on a phantom under standard operating protocols. In this study the optimal workflow to obtain such phantoms from 3D data for interventionist to practice on prior to an actual procedure was investigated. Patientspecific phantoms and phantoms presenting a wide range of challenging geometries were created. Computed Tomographic Angiography (CTA) data was uploaded into a Vitrea 3D station which allows segmentation and resulting stereo-lithographic files to be exported. The files were uploaded using processing software where preloaded vessel structures were included to create a closed-flow vasculature having structural support. The final file was printed, cleaned, connected to a flow loop and placed in an angiographic room for EIGI practice. Various Circle of Willis and cardiac arterial geometries were used. The phantoms were tested for ischemic stroke treatment, distal catheter navigation, aneurysm stenting and cardiac imaging under angiographic guidance. This method should allow for adjustments to treatment plans to be made before the patient is actually in the procedure room and enabling reduced risk of peri-operative complications or delays.

A 4D digital phantom for patient-specific simulation of brain CT perfusion protocols.

Science.gov (United States)

van den Boom, Rieneke; Manniesing, Rashindra; Oei, Marcel T H; van der Woude, Willem-Jan; Smit, Ewoud J; Laue, Hendrik O A; van Ginneken, Bram; Prokop, Mathias

2014-07-01

Optimizing CT brain perfusion protocols is a challenge because of the complex interaction between image acquisition, calculation of perfusion data, and patient hemodynamics. Several digital phantoms have been developed to avoid unnecessary patient exposure or suboptimum choice of parameters. The authors expand this idea by using realistic noise patterns and measured tissue attenuation curves representing patient-specific hemodynamics. The purpose of this work is to validate that this approach can realistically simulate mean perfusion values and noise on perfusion data for individual patients. The proposed 4D digital phantom consists of three major components: (1) a definition of the spatial structure of various brain tissues within the phantom, (2) measured tissue attenuation curves, and (3) measured noise patterns. Tissue attenuation curves were measured in patient data using regions of interest in gray matter and white matter. By assigning the tissue attenuation curves to the corresponding tissue curves within the phantom, patient-specific CTP acquisitions were retrospectively simulated. Noise patterns were acquired by repeatedly scanning an anthropomorphic skull phantom at various exposure settings. The authors selected 20 consecutive patients that were scanned for suspected ischemic stroke and constructed patient-specific 4D digital phantoms using the individual patients' hemodynamics. The perfusion maps of the patient data were compared with the digital phantom data. Agreement between phantom- and patient-derived data was determined for mean perfusion values and for standard deviation in de perfusion data using intraclass correlation coefficients (ICCs) and a linear fit. ICCs ranged between 0.92 and 0.99 for mean perfusion values. ICCs for the standard deviation in perfusion maps were between 0.86 and 0.93. Linear fitting yielded slope values between 0.90 and 1.06. A patient-specific 4D digital phantom allows for realistic simulation of mean values and

A fluid-structure interaction study using patient-specific ruptured and unruptured aneurysm: the effect of aneurysm morphology, hypertension and elasticity.

Science.gov (United States)

Lee, C J; Zhang, Y; Takao, H; Murayama, Y; Qian, Y

2013-09-27

Fluid-structure interaction (FSI) simulations using five patient-specific aneurysm geometries are carried out to investigate the difference between ruptured and unruptured aneurysms. Two different blood pressure conditions (normal and hypertension, for all cases), and two different values of elastic modulus (1 and 2MPa, for two cases) are tested. Ruptured aneurysms (RA) generally displayed larger displacement at the dome, lower area-average WSS and higher von Mises stress than unruptured aneurysms (URA) regardless of elasticity or blood pressure condition. RAs had a longitudinal expansion whereas URAs had a radial expansion, which was the key difference between the two types. The difference in expansion pattern may be one of the keys to explaining aneurysm rupture, and further analysis is required in the future to confirm this theory. Copyright © 2013 Elsevier Ltd. All rights reserved.

Treatment of Wide-Neck Bifurcation Aneurysm Using "WEB Device Waffle Cone Technique".

Science.gov (United States)

Mihalea, Cristian; Caroff, Jildaz; Rouchaud, Aymeric; Pescariu, Sorin; Moret, Jacques; Spelle, Laurent

2018-05-01

The endovascular treatment of wide-neck bifurcation aneurysms can be challenging and often requires the use of adjunctive techniques and devices. We report our first experience of using a waffle-cone technique adapted to the Woven Endoluminal Bridge (WEB) device in a large-neck basilar tip aneurysm, suitable in cases where the use of Y stenting or other techniques is limited due to anatomic restrictions. The procedure was complete, and angiographic occlusion of the aneurysm was achieved 24 hours post treatment, as confirmed by digital subtraction angiography. No complications occurred. The case reported here was not suitable for Y stenting or deployment of the WEB device alone, due to the small caliber of both posterior cerebral arteries and their origin at the neck level. The main advantage of this technique is that both devices have a controlled detachment system and are fully independent. To our knowledge, this technique has not been reported previously and this modality of treatment has never been described in the literature. Copyright © 2018 Elsevier Inc. All rights reserved.

Should indications for WEB aneurysm treatment be enlarged? Report of a series of 20 patients with aneurysms in "atypical" locations for WEB treatment.

Science.gov (United States)

Pierot, L; Biondi, A; Narata, A-P; Mihalea, C; Januel, A-C; Metaxas, G; Bibi, R; Caroff, J; Soize, S; Cognard, C; Spelle, L; Herbreteau, D

2017-06-01

Flow disruption with the WEB device is an innovative technique for the endovascular treatment of wide neck bifurcation aneurysms. Good clinical practice trials have shown high safety of this treatment with good efficacy. Technical developments (single layer devices and smaller microcatheters) facilitate the treatment, potentially leading to enlargement of indications. This series is collecting aneurysms in "atypical" locations for WEB treatment and analyzing safety and efficacy of this treatment. In each participating center, patients with aneurysms treated with WEB were prospectively included in a local database. Patients treated for aneurysms in "atypical" locations were extracted. Patient and aneurysm characteristics, intraoperative complications, and anatomical results at the end of the procedure and at last follow-up were collected and analyzed. Five French neurointerventional centers included 20 patients with 20 aneurysms in "atypical" locations for WEB treatment treated with WEB. Aneurysm locations were ICA carotid-ophthalmic in 9 aneurysms (45.0%), ICA posterior communicating in 4 (20.0%), Pericallosal artery in 5 (25.0%), and basilar artery between P1 and superior cerebellar artery in 2 (10.0%). There were no complications (thromboembolic or intraoperative rupture) in this series. At follow-up (mean: 7.4 months), adequate occlusion was obtained in 100.0% of aneurysms. This series confirms that it is possible to enlarge indications of WEB treatment to "atypical" locations with good safety and efficacy. These data have to be confirmed in large prospective series. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Cerebral Aneurysm Clipping Surgery Simulation Using Patient-Specific 3D Printing and Silicone Casting.

Science.gov (United States)

Ryan, Justin R; Almefty, Kaith K; Nakaji, Peter; Frakes, David H

2016-04-01

Neurosurgery simulator development is growing as practitioners recognize the need for improved instructional and rehearsal platforms to improve procedural skills and patient care. In addition, changes in practice patterns have decreased the volume of specific cases, such as aneurysm clippings, which reduces the opportunity for operating room experience. The authors developed a hands-on, dimensionally accurate model for aneurysm clipping using patient-derived anatomic data and three-dimensional (3D) printing. Design of the model focused on reproducibility as well as adaptability to new patient geometry. A modular, reproducible, and patient-derived medical simulacrum was developed for medical learners to practice aneurysmal clipping procedures. Various forms of 3D printing were used to develop a geometrically accurate cranium and vascular tree featuring 9 patient-derived aneurysms. 3D printing in conjunction with elastomeric casting was leveraged to achieve a patient-derived brain model with tactile properties not yet available from commercial 3D printing technology. An educational pilot study was performed to gauge simulation efficacy. Through the novel manufacturing process, a patient-derived simulacrum was developed for neurovascular surgical simulation. A follow-up qualitative study suggests potential to enhance current educational programs; assessments support the efficacy of the simulacrum. The proposed aneurysm clipping simulator has the potential to improve learning experiences in surgical environment. 3D printing and elastomeric casting can produce patient-derived models for a dynamic learning environment that add value to surgical training and preparation. Copyright © 2016 Elsevier Inc. All rights reserved.

Development of an improved approach to radiation treatment therapy using high-definition patient-specific voxel phantoms

International Nuclear Information System (INIS)

Ward, R.C.; Ryman, J.C.; Worley, B.A.; Stallings, D.C.

1998-01-01

Through an internally funded project at Oak Ridge National Laboratory, a high-resolution phantom was developed based on the National Library of Medicine's Visible Human Data. Special software was written using the interactive data language (IDL) visualization language to automatically segment and classify some of the organs and the skeleton of the Visible Male. A high definition phantom consisting of nine hundred 512 x 512 slices was constructed of the entire torso. Computed tomography (CT) images of a patient's tumor near the spine were scaled and morphed into the phantom model to create a patient-specific phantom. Calculations of dose to the tumor and surrounding tissue were then performed using the patient-specific phantom

Surgical repair of a celiac artery aneurysm using a sutureless proximal anastomosis device

Directory of Open Access Journals (Sweden)

Tetsuro Uchida, MD, PhD

2017-12-01

Full Text Available Some celiac artery aneurysms are not suitable for endovascular therapy. We describe the case of a 63-year-old man with a celiac trunk aneurysm extending to the hepatosplenic bifurcation. The aneurysm was resected and oversewn at the origin from the abdominal aorta. A saphenous vein bypass from the supraceliac aorta to the celiac artery bifurcation was performed using a sutureless anastomotic device (PAS-Port system; Cardica, Redwood City, Calif to create the proximal anastomosis, eliminating the need for aortic clamping. This system is thought to make direct proximal aortic anastomosis safe and easy in patients requiring surgical reconstruction of celiac artery aneurysms.

WE-D-BRA-05: Pseudo In Vivo Patient Dosimetry Using a 3D-Printed Patient-Specific Phantom

International Nuclear Information System (INIS)

Ger, R; Craft, DF; Burgett, EA; Price, RR; Kry, SF; Howell, RM

2015-01-01

Purpose: To test the feasibility of using 3D-printed patient-specific phantoms for intensity-modulated radiation therapy (IMRT) quality assurance (QA). Methods: We created a patient-specific whole-head phantom using a 3D printer. The printer data file was created from high-resolution DICOM computed tomography (CT) images of 3-year old child treated at our institution for medulloblastoma. A custom-modified extruder system was used to create tissue-equivalent materials. For the printing process, the Hounsfield Units from the CT images were converted to proportional volumetric densities. A 5-field IMRT plan was created from the patient CT and delivered to the 3D- phantom. Dose was measured by an ion chamber placed through the eye. The ion chamber was placed at the posterior edge of the planning target volume in a high dose gradient region. CT scans of the patient and 3D-phantom were fused by using commercial treatment planning software (TPS). The patient’s plan was calculated on the phantom CT images. The ion chamber’s active volume was delineated in the TPS; dose per field and total dose were obtained. Measured and calculated doses were compared. Results: The 3D-phantom dimensions and tissue densities were in good agreement with the patient. However, because of a printing error, there was a large discrepancy in the density in the frontal cortex. The calculated and measured treatment plan doses were 1.74 Gy and 1.72 Gy, respectively. For individual fields, the absolute dose difference between measured and calculated values was on average 3.50%. Conclusion: This study demonstrated the feasibility of using 3D-printed patient-specific phantoms for IMRT QA. Such phantoms would be particularly advantageous for complex IMRT treatment plans featuring high dose gradients and/or for anatomical sites with high variation in tissue densities. Our preliminary findings are promising. We anticipate that, once the printing process is further refined, the agreement between

WE-D-BRA-05: Pseudo In Vivo Patient Dosimetry Using a 3D-Printed Patient-Specific Phantom

Energy Technology Data Exchange (ETDEWEB)

Ger, R; Craft, DF [The University of Texas Graduate School of Biomedical Sciences (United States); Burgett, EA [Idaho State University, Pocatello, idaho (United States); Price, RR [RANDJ Consulting, Frederick, MD (United States); Kry, SF; Howell, RM [The University of Texas Graduate School of Biomedical Sciences (United States); The University of Texas MD Anderson Cancer Ctr., Houston, TX (United States)

2015-06-15

Purpose: To test the feasibility of using 3D-printed patient-specific phantoms for intensity-modulated radiation therapy (IMRT) quality assurance (QA). Methods: We created a patient-specific whole-head phantom using a 3D printer. The printer data file was created from high-resolution DICOM computed tomography (CT) images of 3-year old child treated at our institution for medulloblastoma. A custom-modified extruder system was used to create tissue-equivalent materials. For the printing process, the Hounsfield Units from the CT images were converted to proportional volumetric densities. A 5-field IMRT plan was created from the patient CT and delivered to the 3D- phantom. Dose was measured by an ion chamber placed through the eye. The ion chamber was placed at the posterior edge of the planning target volume in a high dose gradient region. CT scans of the patient and 3D-phantom were fused by using commercial treatment planning software (TPS). The patient’s plan was calculated on the phantom CT images. The ion chamber’s active volume was delineated in the TPS; dose per field and total dose were obtained. Measured and calculated doses were compared. Results: The 3D-phantom dimensions and tissue densities were in good agreement with the patient. However, because of a printing error, there was a large discrepancy in the density in the frontal cortex. The calculated and measured treatment plan doses were 1.74 Gy and 1.72 Gy, respectively. For individual fields, the absolute dose difference between measured and calculated values was on average 3.50%. Conclusion: This study demonstrated the feasibility of using 3D-printed patient-specific phantoms for IMRT QA. Such phantoms would be particularly advantageous for complex IMRT treatment plans featuring high dose gradients and/or for anatomical sites with high variation in tissue densities. Our preliminary findings are promising. We anticipate that, once the printing process is further refined, the agreement between

Fluid-structure interaction of a patient-specific abdominal aortic aneurysm treated with an endovascular stent-graft.

LENUS (Irish Health Repository)

Molony, David S

2009-01-01

BACKGROUND: Abdominal aortic aneurysms (AAA) are local dilatations of the infrarenal aorta. If left untreated they may rupture and lead to death. One form of treatment is the minimally invasive insertion of a stent-graft into the aneurysm. Despite this effective treatment aneurysms may occasionally continue to expand and this may eventually result in post-operative rupture of the aneurysm. Fluid-structure interaction (FSI) is a particularly useful tool for investigating aneurysm biomechanics as both the wall stresses and fluid forces can be examined. METHODS: Pre-op, Post-op and Follow-up models were reconstructed from CT scans of a single patient and FSI simulations were performed on each model. The FSI approach involved coupling Abaqus and Fluent via a third-party software - MpCCI. Aneurysm wall stress and compliance were investigated as well as the drag force acting on the stent-graft. RESULTS: Aneurysm wall stress was reduced from 0.38 MPa before surgery to a value of 0.03 MPa after insertion of the stent-graft. Higher stresses were seen in the aneurysm neck and iliac legs post-operatively. The compliance of the aneurysm was also reduced post-operatively. The peak Post-op axial drag force was found to be 4.85 N. This increased to 6.37 N in the Follow-up model. CONCLUSION: In a patient-specific case peak aneurysm wall stress was reduced by 92%. Such a reduction in aneurysm wall stress may lead to shrinkage of the aneurysm over time. Hence, post-operative stress patterns may help in determining the likelihood of aneurysm shrinkage post EVAR. Post-operative remodelling of the aneurysm may lead to increased drag forces.

Influence of the Accuracy of Angiography-Based Reconstructions on Velocity and Wall Shear Stress Computations in Coronary Bifurcations: A Phantom Study

Science.gov (United States)

Schrauwen, Jelle T. C.; Karanasos, Antonios; van Ditzhuijzen, Nienke S.; Aben, Jean-Paul; van der Steen, Antonius F. W.

2015-01-01

Introduction Wall shear stress (WSS) plays a key role in the onset and progression of atherosclerosis in human coronary arteries. Especially sites with low and oscillating WSS near bifurcations have a higher propensity to develop atherosclerosis. WSS computations in coronary bifurcations can be performed in angiography-based 3D reconstructions. It is essential to evaluate how reconstruction errors influence WSS computations in mildly-diseased coronary bifurcations. In mildly-diseased lesions WSS could potentially provide more insight in plaque progression. Materials Methods Four Plexiglas phantom models of coronary bifurcations were imaged with bi-plane angiography. The lumens were segmented by two clinically experienced readers. Based on the segmentations 3D models were generated. This resulted in three models per phantom: one gold-standard from the phantom model itself, and one from each reader. Steady-state and transient simulations were performed with computational fluid dynamics to compute the WSS. A similarity index and a noninferiority test were used to compare the WSS in the phantoms and their reconstructions. The margin for this test was based on the resolution constraints of angiography. Results The reconstruction errors were similar to previously reported data; in seven out of eight reconstructions less than 0.10 mm. WSS in the regions proximal and far distal of the stenosis showed a good agreement. However, the low WSS areas directly distal of the stenosis showed some disagreement between the phantoms and the readers. This was due to small deviations in the reconstruction of the stenosis that caused differences in the resulting jet, and consequently the size and location of the low WSS area. Discussion This study showed that WSS can accurately be computed within angiography-based 3D reconstructions of coronary arteries with early stage atherosclerosis. Qualitatively, there was a good agreement between the phantoms and the readers. Quantitatively, the

Influence of the Accuracy of Angiography-Based Reconstructions on Velocity and Wall Shear Stress Computations in Coronary Bifurcations: A Phantom Study.

Directory of Open Access Journals (Sweden)

Jelle T C Schrauwen

Full Text Available Wall shear stress (WSS plays a key role in the onset and progression of atherosclerosis in human coronary arteries. Especially sites with low and oscillating WSS near bifurcations have a higher propensity to develop atherosclerosis. WSS computations in coronary bifurcations can be performed in angiography-based 3D reconstructions. It is essential to evaluate how reconstruction errors influence WSS computations in mildly-diseased coronary bifurcations. In mildly-diseased lesions WSS could potentially provide more insight in plaque progression.Four Plexiglas phantom models of coronary bifurcations were imaged with bi-plane angiography. The lumens were segmented by two clinically experienced readers. Based on the segmentations 3D models were generated. This resulted in three models per phantom: one gold-standard from the phantom model itself, and one from each reader. Steady-state and transient simulations were performed with computational fluid dynamics to compute the WSS. A similarity index and a noninferiority test were used to compare the WSS in the phantoms and their reconstructions. The margin for this test was based on the resolution constraints of angiography.The reconstruction errors were similar to previously reported data; in seven out of eight reconstructions less than 0.10 mm. WSS in the regions proximal and far distal of the stenosis showed a good agreement. However, the low WSS areas directly distal of the stenosis showed some disagreement between the phantoms and the readers. This was due to small deviations in the reconstruction of the stenosis that caused differences in the resulting jet, and consequently the size and location of the low WSS area.This study showed that WSS can accurately be computed within angiography-based 3D reconstructions of coronary arteries with early stage atherosclerosis. Qualitatively, there was a good agreement between the phantoms and the readers. Quantitatively, the low WSS regions directly distal to

Blood flow dynamic improvement with aneurysm repair detected by a patient-specific model of multiple aortic aneurysms.

Science.gov (United States)

Sughimoto, Koichi; Takahara, Yoshiharu; Mogi, Kenji; Yamazaki, Kenji; Tsubota, Ken'ichi; Liang, Fuyou; Liu, Hao

2014-05-01

Aortic aneurysms may cause the turbulence of blood flow and result in the energy loss of the blood flow, while grafting of the dilated aorta may ameliorate these hemodynamic disturbances, contributing to the alleviation of the energy efficiency of blood flow delivery. However, evaluating of the energy efficiency of blood flow in an aortic aneurysm has been technically difficult to estimate and not comprehensively understood yet. We devised a multiscale computational biomechanical model, introducing novel flow indices, to investigate a single male patient with multiple aortic aneurysms. Preoperative levels of wall shear stress and oscillatory shear index (OSI) were elevated but declined after staged grafting procedures: OSI decreased from 0.280 to 0.257 (first operation) and 0.221 (second operation). Graftings may strategically counter the loss of efficient blood delivery to improve hemodynamics of the aorta. The energy efficiency of blood flow also improved postoperatively. Novel indices of pulsatile pressure index (PPI) and pulsatile energy loss index (PELI) were evaluated to characterize and quantify energy loss of pulsatile blood flow. Mean PPI decreased from 0.445 to 0.423 (first operation) and 0.359 (second operation), respectively; while the preoperative PELI of 0.986 dropped to 0.820 and 0.831. Graftings contributed not only to ameliorate wall shear stress or oscillatory shear index but also to improve efficient blood flow. This patient-specific modeling will help in analyzing the mechanism of aortic aneurysm formation and may play an important role in quantifying the energy efficiency or loss in blood delivery.

Three-dimensional printer-generated patient-specific phantom for artificial in vivo dosimetry in radiotherapy quality assurance.

Science.gov (United States)

Kamomae, Takeshi; Shimizu, Hidetoshi; Nakaya, Takayoshi; Okudaira, Kuniyasu; Aoyama, Takahiro; Oguchi, Hiroshi; Komori, Masataka; Kawamura, Mariko; Ohtakara, Kazuhiro; Monzen, Hajime; Itoh, Yoshiyuki; Naganawa, Shinji

2017-12-01

Pretreatment intensity-modulated radiotherapy quality assurance is performed using simple rectangular or cylindrical phantoms; thus, the dosimetric errors caused by complex patient-specific anatomy are absent in the evaluation objects. In this study, we construct a system for generating patient-specific three-dimensional (3D)-printed phantoms for radiotherapy dosimetry. An anthropomorphic head phantom containing the bone and hollow of the paranasal sinus is scanned by computed tomography (CT). Based on surface rendering data, a patient-specific phantom is formed using a fused-deposition-modeling-based 3D printer, with a polylactic acid filament as the printing material. Radiophotoluminescence glass dosimeters can be inserted in the 3D-printed phantom. The phantom shape, CT value, and absorbed doses are compared between the actual and 3D-printed phantoms. The shape difference between the actual and printed phantoms is less than 1 mm except in the bottom surface region. The average CT value of the infill region in the 3D-printed phantom is -6 ± 18 Hounsfield units (HU) and that of the vertical shell region is 126 ± 18 HU. When the same plans were irradiated, the dose differences were generally less than 2%. These results demonstrate the feasibility of the 3D-printed phantom for artificial in vivo dosimetry in radiotherapy quality assurance. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Suture retraction technique to prevent parent vessel obstruction following aneurysm tandem clipping.

Science.gov (United States)

Rayan, Tarek; Amin-Hanjani, Sepideh

2015-08-01

With large or giant aneurysms, the use of multiple tandem clips can be essential for complete obliteration of the aneurysm. One potential disadvantage, however, is the considerable cumulative weight of these clips, which may lead to kinking of the underlying parent vessels and obstruction of flow. The authors describe a simple technique to address this problem, guided by intraoperative blood flow measurements, in a patient with a ruptured near-giant 2.2 × 1.7-cm middle cerebral artery bifurcation aneurysm that was treated with the tandem clipping technique. A total of 11 clips were applied in a vertical stacked fashion. The cumulative weight of the clips caused kinking of the temporal M2 branch of the bifurcation with reduction of flow. A 4-0 Nurolon suture tie was applied to the hub of one of the clips and was tethered to the dura of the sphenoid ridge by a small mini-clip and reinforced by application of tissue sealant. The patient underwent intraoperative indocyanine green videoangiography as well as catheter angiography, which demonstrated complete aneurysmal obliteration and preservation of vessel branches. Postoperative angiography confirmed patency of the bifurcation vessels with mild vasospasm. The patient had a full recovery with no postoperative complications and was neurologically intact at her 6-month follow-up. The suture retraction technique allows a simple solution to parent vessel obstruction following aneurysm tandem clipping, in conjunction with the essential guidance provided by intraoperative flow measurements.

A multimodality vascular imaging phantom of an abdominal aortic aneurysm with a visible thrombus

Energy Technology Data Exchange (ETDEWEB)

Allard, Louise; Chayer, Boris; Qin Zhao [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital (CRCHUM), Quebec H2L 2W5 (Canada); Soulez, Gilles [Department of Radiology, University of Montreal Hospital (CHUM), Quebec H2L 2M1 (Canada); Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Quebec H3T 1J4 (Canada); Institute of Biomedical Engineering, University of Montreal, Quebec H3T 1J4 (Canada); Roy, David [Institute of Biomedical Engineering, University of Montreal, Quebec H3T 1J4 (Canada); Cloutier, Guy [Laboratory of Biorheology and Medical Ultrasonics, Research Center, University of Montreal Hospital (CRCHUM), Quebec H2L 2W5 (Canada); Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Quebec H3T 1J4 (Canada); Institute of Biomedical Engineering, University of Montreal, Quebec H3T 1J4 (Canada)

2013-06-15

Purpose: With the continuous development of new stent grafts and implantation techniques, it has now become technically feasible to treat abdominal aortic aneurysms (AAA) with challenging anatomy using endovascular repair with standard, fenestrated, or branched stent-grafts. In vitro experimentations are very useful to improve stent-graft design and conformability or imaging guidance for stent-graft delivery or follow-up. Vascular replicas also help to better understand the limitation of endovascular approaches in challenging anatomy and possibly improve surgical planning or training by practicing high risk clinical procedures in the laboratory to improve outcomes in the operating room. Most AAA phantoms available have a very basic anatomy, which is not representative of the clinical reality. This paper presents a method of fabrication of a realistic AAA phantom with a visible thrombus, as well as some mechanical properties characterizing such phantom. Methods: A realistic AAA geometry replica of a real patient anatomy taken from a multidetector computed tomography (CT) scan was manufactured. To demonstrate the multimodality imaging capability of this new phantom with a thrombus visible in magnetic resonance (MR) angiography, CT angiography (CTA), digital subtraction angiography (DSA), and ultrasound, image acquisitions with all these modalities were performed by using standard clinical protocols. Potential use of this phantom for stent deployment was also tested. A rheometer allowed defining hyperelastic and viscoelastic properties of phantom materials. Results: MR imaging measurements of SNR and CNR values on T1 and T2-weighted sequences and MR angiography indicated reasonable agreement with published values of AAA thrombus and abdominal components in vivo. X-ray absorption also lay within normal ranges of AAA patients and was representative of findings observed on CTA, fluoroscopy, and DSA. Ultrasound propagation speeds for developed materials were also in

A multimodality vascular imaging phantom of an abdominal aortic aneurysm with a visible thrombus

International Nuclear Information System (INIS)

Allard, Louise; Chayer, Boris; Qin Zhao; Soulez, Gilles; Roy, David; Cloutier, Guy

2013-01-01

Purpose: With the continuous development of new stent grafts and implantation techniques, it has now become technically feasible to treat abdominal aortic aneurysms (AAA) with challenging anatomy using endovascular repair with standard, fenestrated, or branched stent-grafts. In vitro experimentations are very useful to improve stent-graft design and conformability or imaging guidance for stent-graft delivery or follow-up. Vascular replicas also help to better understand the limitation of endovascular approaches in challenging anatomy and possibly improve surgical planning or training by practicing high risk clinical procedures in the laboratory to improve outcomes in the operating room. Most AAA phantoms available have a very basic anatomy, which is not representative of the clinical reality. This paper presents a method of fabrication of a realistic AAA phantom with a visible thrombus, as well as some mechanical properties characterizing such phantom. Methods: A realistic AAA geometry replica of a real patient anatomy taken from a multidetector computed tomography (CT) scan was manufactured. To demonstrate the multimodality imaging capability of this new phantom with a thrombus visible in magnetic resonance (MR) angiography, CT angiography (CTA), digital subtraction angiography (DSA), and ultrasound, image acquisitions with all these modalities were performed by using standard clinical protocols. Potential use of this phantom for stent deployment was also tested. A rheometer allowed defining hyperelastic and viscoelastic properties of phantom materials. Results: MR imaging measurements of SNR and CNR values on T1 and T2-weighted sequences and MR angiography indicated reasonable agreement with published values of AAA thrombus and abdominal components in vivo. X-ray absorption also lay within normal ranges of AAA patients and was representative of findings observed on CTA, fluoroscopy, and DSA. Ultrasound propagation speeds for developed materials were also in

Challenges and limitations of patient-specific vascular phantom fabrication using 3D Polyjet printing

Science.gov (United States)

Ionita, Ciprian N.; Mokin, Maxim; Varble, Nicole; Bednarek, Daniel R.; Xiang, Jianping; Snyder, Kenneth V.; Siddiqui, Adnan H.; Levy, Elad I.; Meng, Hui; Rudin, Stephen

2014-03-01

Additive manufacturing (3D printing) technology offers a great opportunity towards development of patient-specific vascular anatomic models, for medical device testing and physiological condition evaluation. However, the development process is not yet well established and there are various limitations depending on the printing materials, the technology and the printer resolution. Patient-specific neuro-vascular anatomy was acquired from computed tomography angiography and rotational digital subtraction angiography (DSA). The volumes were imported into a Vitrea 3D workstation (Vital Images Inc.) and the vascular lumen of various vessels and pathologies were segmented using a "marching cubes" algorithm. The results were exported as Stereo Lithographic (STL) files and were further processed by smoothing, trimming, and wall extrusion (to add a custom wall to the model). The models were printed using a Polyjet printer, Eden 260V (Objet-Stratasys). To verify the phantom geometry accuracy, the phantom was reimaged using rotational DSA, and the new data was compared with the initial patient data. The most challenging part of the phantom manufacturing was removal of support material. This aspect could be a serious hurdle in building very tortuous phantoms or small vessels. The accuracy of the printed models was very good: distance analysis showed average differences of 120 μm between the patient and the phantom reconstructed volume dimensions. Most errors were due to residual support material left in the lumen of the phantom. Despite the post-printing challenges experienced during the support cleaning, this technology could be a tremendous benefit to medical research such as in device development and testing.

Hemodynamics of a Patient-Specific Aneurysm Model with Proper Orthogonal Decomposition

Science.gov (United States)

Han, Suyue; Chang, Gary Han; Modarres-Sadeghi, Yahya

2017-11-01

Wall shear stress (WSS) and oscillatory shear index (OSI) are two of the most-widely studied hemodynamic quantities in cardiovascular systems that have been shown to have the ability to elicit biological responses of the arterial wall, which could be used to predict the aneurysm development and rupture. In this study, a reduced-order model (ROM) of the hemodynamics of a patient-specific cerebral aneurysm is studied. The snapshot Proper Orthogonal Decomposition (POD) is utilized to construct the reduced-order bases of the flow using a CFD training set with known inflow parameters. It was shown that the area of low WSS and high OSI is correlated to higher POD modes. The resulting ROM can reproduce both WSS and OSI computationally for future parametric studies with significantly less computational cost. Agreement was observed between the WSS and OSI values obtained using direct CFD results and ROM results.

SU-F-BRE-08: Feasibility of 3D Printed Patient Specific Phantoms for IMRT/IGRT QA

International Nuclear Information System (INIS)

Ehler, E; Higgins, P; Dusenbery, K

2014-01-01

Purpose: Test the feasibility of 3D printed, per-patient phantoms for IMRT QA to analyze the treatment delivery quality within the patient geometry. Methods: Using the head and neck region of an anthropomorphic phantom as a substitute for an actual patient, a soft-tissue equivalent model was constructed with the use of a 3D printer. A nine-field IMRT plan was constructed and dose verification measurements were performed for the 3D printed phantom. During the delivery of the IMRT QA on to the 3D printed phantom, the same patient positioning indexing system was used on the phantom and image guidance (cone beam CT) was used to localize the phantom, serving as a test of the IGRT system as well. The 3D printed phantom was designed to accommodate four radiochromic film planes (two axial, one coronal and one sagittal) and an ionization chamber measurement. As a frame of comparison, the IMRT QA was also performed on traditional phantoms. Dosimetric tolerance levels such as 3mm / 3% Gamma Index as well as 3% and 5% dose difference were considered. All detector systems were calibrated against a NIST traceable ionization chamber. Results: Comparison of results 3D printed patient phantom with the standard IMRT QA systems showed similar passing rates for the 3D printed phantom and the standard phantoms. However, the locations of the failing regions did not necessarily correlate. The 3D printed phantom was localized within 1 mm and 1° using on-board cone beam CT. Conclusion: A custom phantom was created using a 3D printer. It was determined that the use of patient specific phantoms to perform dosimetric verification and estimate the dose in the patient is feasible. In addition, end-to-end testing on a per-patient basis was possible with the 3D printed phantom. Further refinement of the phantom construction process is needed for routine clinical use

SU-F-BRE-08: Feasibility of 3D Printed Patient Specific Phantoms for IMRT/IGRT QA

Energy Technology Data Exchange (ETDEWEB)

Ehler, E; Higgins, P; Dusenbery, K [University of Minnesota, Minneapolis, MN (United States)

2014-06-15

Purpose: Test the feasibility of 3D printed, per-patient phantoms for IMRT QA to analyze the treatment delivery quality within the patient geometry. Methods: Using the head and neck region of an anthropomorphic phantom as a substitute for an actual patient, a soft-tissue equivalent model was constructed with the use of a 3D printer. A nine-field IMRT plan was constructed and dose verification measurements were performed for the 3D printed phantom. During the delivery of the IMRT QA on to the 3D printed phantom, the same patient positioning indexing system was used on the phantom and image guidance (cone beam CT) was used to localize the phantom, serving as a test of the IGRT system as well. The 3D printed phantom was designed to accommodate four radiochromic film planes (two axial, one coronal and one sagittal) and an ionization chamber measurement. As a frame of comparison, the IMRT QA was also performed on traditional phantoms. Dosimetric tolerance levels such as 3mm / 3% Gamma Index as well as 3% and 5% dose difference were considered. All detector systems were calibrated against a NIST traceable ionization chamber. Results: Comparison of results 3D printed patient phantom with the standard IMRT QA systems showed similar passing rates for the 3D printed phantom and the standard phantoms. However, the locations of the failing regions did not necessarily correlate. The 3D printed phantom was localized within 1 mm and 1° using on-board cone beam CT. Conclusion: A custom phantom was created using a 3D printer. It was determined that the use of patient specific phantoms to perform dosimetric verification and estimate the dose in the patient is feasible. In addition, end-to-end testing on a per-patient basis was possible with the 3D printed phantom. Further refinement of the phantom construction process is needed for routine clinical use.

SU-E-T-114: Analysis of MLC Errors On Gamma Pass Rates for Patient-Specific and Conventional Phantoms

Energy Technology Data Exchange (ETDEWEB)

Sterling, D; Ehler, E [University of Minnesota, Minneapolis, MN (United States)

2015-06-15

Purpose: To evaluate whether a 3D patient-specific phantom is better able to detect known MLC errors in a clinically delivered treatment plan than conventional phantoms. 3D printing may make fabrication of such phantoms feasible. Methods: Two types of MLC errors were introduced into a clinically delivered, non-coplanar IMRT, partial brain treatment plan. First, uniformly distributed random errors of up to 3mm, 2mm, and 1mm were introduced into the MLC positions for each field. Second, systematic MLC-bank position errors of 5mm, 3.5mm, and 2mm due to simulated effects of gantry and MLC sag were introduced. The original plan was recalculated with these errors on the original CT dataset as well as cylindrical and planar IMRT QA phantoms. The original dataset was considered to be a perfect 3D patient-specific phantom. The phantoms were considered to be ideal 3D dosimetry systems with no resolution limitations. Results: Passing rates for Gamma Index (3%/3mm and no dose threshold) were calculated on the 3D phantom, cylindrical phantom, and both on a composite and field-by-field basis for the planar phantom. Pass rates for 5mm systematic and 3mm random error were 86.0%, 89.6%, 98% and 98.3% respectively. For 3.5mm systematic and 2mm random error the pass rates were 94.7%, 96.2%, 99.2% and 99.2% respectively. For 2mm systematic error with 1mm random error the pass rates were 99.9%, 100%, 100% and 100% respectively. Conclusion: A 3D phantom with the patient anatomy is able to discern errors, both severe and subtle, that are not seen using conventional phantoms. Therefore, 3D phantoms may be beneficial for commissioning new treatment machines and modalities, patient-specific QA and end-to-end testing.

SU-E-T-114: Analysis of MLC Errors On Gamma Pass Rates for Patient-Specific and Conventional Phantoms

International Nuclear Information System (INIS)

Sterling, D; Ehler, E

2015-01-01

Purpose: To evaluate whether a 3D patient-specific phantom is better able to detect known MLC errors in a clinically delivered treatment plan than conventional phantoms. 3D printing may make fabrication of such phantoms feasible. Methods: Two types of MLC errors were introduced into a clinically delivered, non-coplanar IMRT, partial brain treatment plan. First, uniformly distributed random errors of up to 3mm, 2mm, and 1mm were introduced into the MLC positions for each field. Second, systematic MLC-bank position errors of 5mm, 3.5mm, and 2mm due to simulated effects of gantry and MLC sag were introduced. The original plan was recalculated with these errors on the original CT dataset as well as cylindrical and planar IMRT QA phantoms. The original dataset was considered to be a perfect 3D patient-specific phantom. The phantoms were considered to be ideal 3D dosimetry systems with no resolution limitations. Results: Passing rates for Gamma Index (3%/3mm and no dose threshold) were calculated on the 3D phantom, cylindrical phantom, and both on a composite and field-by-field basis for the planar phantom. Pass rates for 5mm systematic and 3mm random error were 86.0%, 89.6%, 98% and 98.3% respectively. For 3.5mm systematic and 2mm random error the pass rates were 94.7%, 96.2%, 99.2% and 99.2% respectively. For 2mm systematic error with 1mm random error the pass rates were 99.9%, 100%, 100% and 100% respectively. Conclusion: A 3D phantom with the patient anatomy is able to discern errors, both severe and subtle, that are not seen using conventional phantoms. Therefore, 3D phantoms may be beneficial for commissioning new treatment machines and modalities, patient-specific QA and end-to-end testing

Effect of exercise on patient specific abdominal aortic aneurysm flow topology and mixing.

Science.gov (United States)

Arzani, Amirhossein; Les, Andrea S; Dalman, Ronald L; Shadden, Shawn C

2014-02-01

Computational fluid dynamics modeling was used to investigate changes in blood transport topology between rest and exercise conditions in five patient-specific abdominal aortic aneurysm models. MRI was used to provide the vascular anatomy and necessary boundary conditions for simulating blood velocity and pressure fields inside each model. Finite-time Lyapunov exponent fields and associated Lagrangian coherent structures were computed from blood velocity data and were used to compare features of the transport topology between rest and exercise both mechanistically and qualitatively. A mix-norm and mix-variance measure based on fresh blood distribution throughout the aneurysm over time were implemented to quantitatively compare mixing between rest and exercise. Exercise conditions resulted in higher and more uniform mixing and reduced the overall residence time in all aneurysms. Separated regions of recirculating flow were commonly observed in rest, and these regions were either reduced or removed by attached and unidirectional flow during exercise, or replaced with regional chaotic and transiently turbulent mixing, or persisted and even extended during exercise. The main factor that dictated the change in flow topology from rest to exercise was the behavior of the jet of blood penetrating into the aneurysm during systole. Copyright © 2013 John Wiley & Sons, Ltd.

Cranio-orbital approach for complex aneurysmal surgery.

LENUS (Irish Health Repository)

Kelleher, M O

2012-02-03

Certain aneurysms of the anterior circulation continue to offer a technical challenge for safe exposure and clipping. The purpose of this paper was to describe the cranio-orbital approach for surgical clipping of complex aneurysms and to evaluate prospectively the associated complications of this approach. Prospective audit of all patients undergoing cranio-orbital approach for aneurysm surgery from 1997 to 2004 by the senior author. Twenty-five patients, eight male and 17 female, median age of 52 years, range 28-73. All patients had a standard pterional approach supplemented by an orbital osteotomy. In the 7-year period 367 patients underwent treatment for their aneurysms (169 clipped and 198 coiled). Of the 169 patients who were operated on, 29 had a skull base approach, of which 25 were cranio-orbital. The aneurysm location was as follows: 16 middle cerebral artery (MCA), three carotid bifurcation, four anterior communicating artery (ACOMM), one ophthalmic and one basilar. There were no approach-related complications. The cranio-orbital craniotomy can be a useful adjunct in the surgical treatment of giant or complex aneurysms. It offers the following advantages over a standard pterional approach: reduces operative distance; allows easy splitting of the sylvian fissure; and provides a wide arc of exposure with multiple working corridors.

Construct canine intracranial aneurysm model by endovascular technique

International Nuclear Information System (INIS)

Liang Xiaodong; Liu Yizhi; Ni Caifang; Ding Yi

2004-01-01

Objective: To construct canine bifurcation aneurysms suitable for evaluating the exploration of endovascular devices for interventional therapy by endovascular technique. Methods: The right common carotid artery of six dogs was expanded with a pliable balloon by means of endovascular technique, then embolization with detached balloon was taken at their originations DAS examination were performed on 1, 2, 3 d after the procedurse. Results: 6 aneurysm models were created in six dogs successfully with the mean width and height of the aneurysms decreasing in 3 days. Conclusions: This canine aneurysm model presents the virtue in the size and shape of human cerebral bifurcation saccular aneurysms on DSA image, suitable for developing the exploration of endovascular devices for aneurismal therapy. The procedure is quick, reliable and reproducible. (authors)

Intracranial aneurysms: evaluation in 200 patients with spiral CT angiography

International Nuclear Information System (INIS)

Young, N.; Kingston, R.J.; Markson, G.; Dorsch, N.W.C.; McMahon, J.

2001-01-01

The goal of this study was to assess the usefulness of spiral CT angiography (CTA) with three- dimensional reconstructions in defining intracranial aneurysms, particularly around the Circle of Willis. Two hundred consecutive patients with angiographic and/or surgical correlation were studied between 1993 and 1998, with CTA performed on a GE HiSpeed unit and Windows workstation. The following clinical situations were evaluated: conventional CT suspicion of an aneurysm; follow-up of treated aneurysm remnants or of untreated aneurysms; subarachnoid haemorrhage (SAH) and negative angiography; family or past aneurysm history; and for improved definition of aneurysm anatomy. Spiral CTA detected 140 of 144 aneurysms, and an overall sensitivity of 97%, including 30 of 32 aneurysms 3 mm or less in size. In 38 patients with SAH and negative angiography, CTA found six of the seven aneurysms finally diagnosed. There was no significant artefact in 17 of 23 patients (74%) with clips. The specificity of CTA was 86% with 8 false-positive cases. Spiral CTA is very useful in demonstrating intracranial aneurysms. (orig.)

Usefulness of PC based 3D volume rendering technique in the evaluation of suspected aneurysm on brain MRA

International Nuclear Information System (INIS)

Baek, Seung Il; Lee, Ghi Jai; Shim, Jae Chan; Bang, Sun Woo; Ryu, Seok Jong; Kim, Ho Kyun

2002-01-01

To evaluated usefulness of volume rending technique using 3D visualization software on PC in patients with suspected intracranial aneurysm on brain MRA. We analyzed prospectively 21 patients with suspected aneurysms on the routine MIP images which were obtained 15 .deg. C increment along axial and sagittal plane, among 135 patients in whom brain MRA was done due to stroke symptoms for recent 5 months. The locations were the anterior communicating artery (A-com) in 8 patients, the posterior communicating artery (P-com) in 3, the ICA bifurcation in 5, the MCA bifurcation in 4, and the basilar tip in one. Male to female ratio was 14:7 and mean age was 62 years. MRA source images were sent to PC through LAN, and the existence of aneurysm was evaluated with volume rendering technique using 3D visualization software on PC. The presence or absence of aneurysm on MIP and volume rendering images was decided by the consensus of two radiologists. We found the aneurysms with volume rendering technique, from 1 patient among 8 patients with suspected aneurysm at A-com and also 1 patient among 3 patients with suspected aneurysm at P=com on routine MIP images. Confirmative angiography and interventional procedures were done in these 2 patients. The causes for mimicking the aneurysm on MIP were flow displacement artifact in 9, normal P-com infundibulum in 2, and overlapped or narrowed vessels in 8 patients, and among them confirmative angiography was done in 2 patient. Volume rendering technique using visualization software on PC is useful to scrutinize the suspected aneurysm on routine MIP images and to avoid further invasive angiography

An anatomic risk model to screen post endovascular aneurysm repair patients for aneurysm sac enlargement.

Science.gov (United States)

Png, Chien Yi M; Tadros, Rami O; Beckerman, William E; Han, Daniel K; Tardiff, Melissa L; Torres, Marielle R; Marin, Michael L; Faries, Peter L

2017-09-01

Follow-up computed tomography angiography (CTA) scans add considerable postimplantation costs to endovascular aneurysm repairs (EVARs) of abdominal aortic aneurysms (AAAs). By building a risk model, we hope to identify patients at low risk for aneurysm sac enlargement to minimize unnecessary CTAs. 895 consecutive patients who underwent EVAR for AAA were reviewed, of which 556 met inclusion criteria. A Probit model was created for aneurysm sac enlargement, with preoperative aneurysm morphology, patient demographics, and operative details as variables. Our final model included 287 patients and had a sensitivity of 100%, a specificity of 68.9%, and an accuracy of 70.4%. Ninety-nine (35%) of patients were assigned to the high-risk group, whereas 188 (65%) of patients were assigned to the low-risk group. Notably, regarding anatomic variables, our model reported that age, pulmonary comorbidities, aortic neck diameter, iliac artery length, and aneurysms were independent predictors of post-EVAR sac enlargement. With the exception of age, all statistically significant variables were qualitatively supported by prior literature. With regards to secondary outcomes, the high-risk group had significantly higher proportions of AAA-related deaths (5.1% versus 1.1%, P = 0.037) and Type 1 endoleaks (9.1% versus 3.2%, P = 0.033). Our model is a decent predictor of patients at low risk for post AAA EVAR aneurysm sac enlargement and associated complications. With additional validation and refinement, it could be applied to practices to cut down on the overall need for postimplantation CTA. Copyright © 2017 Elsevier Inc. All rights reserved.

The impact of anthropometric patient-phantom matching on organ dose: A hybrid phantom study for fluoroscopy guided interventions

International Nuclear Information System (INIS)

Johnson, Perry B.; Geyer, Amy; Borrego, David; Ficarrotta, Kayla; Johnson, Kevin; Bolch, Wesley E.

2011-01-01

Purpose: To investigate the benefits and limitations of patient-phantom matching for determining organ dose during fluoroscopy guided interventions. Methods: In this study, 27 CT datasets representing patients of different sizes and genders were contoured and converted into patient-specific computational models. Each model was matched, based on height and weight, to computational phantoms selected from the UF hybrid patient-dependent series. In order to investigate the influence of phantom type on patient organ dose, Monte Carlo methods were used to simulate two cardiac projections (PA/left lateral) and two abdominal projections (RAO/LPO). Organ dose conversion coefficients were then calculated for each patient-specific and patient-dependent phantom and also for a reference stylized and reference hybrid phantom. The coefficients were subsequently analyzed for any correlation between patient-specificity and the accuracy of the dose estimate. Accuracy was quantified by calculating an absolute percent difference using the patient-specific dose conversion coefficients as the reference. Results: Patient-phantom matching was shown most beneficial for estimating the dose to heavy patients. In these cases, the improvement over using a reference stylized phantom ranged from approximately 50% to 120% for abdominal projections and for a reference hybrid phantom from 20% to 60% for all projections. For lighter individuals, patient-phantom matching was clearly superior to using a reference stylized phantom, but not significantly better than using a reference hybrid phantom for certain fields and projections. Conclusions: The results indicate two sources of error when patients are matched with phantoms: Anatomical error, which is inherent due to differences in organ size and location, and error attributed to differences in the total soft tissue attenuation. For small patients, differences in soft tissue attenuation are minimal and are exceeded by inherent anatomical differences

Traumatic aneurysms of the pericallosal arteries

International Nuclear Information System (INIS)

Nakstad, P.; Nornes, H.; Hauge, H.N.

1986-01-01

Of a total of 912 operated intracranial aneurysms only three were classified as traumatic (0.3%). They were found in children after severe head trauma and were all located on the pericallosal artery or its branches and not a bifurcations. Shearing forces between the falx, the arteries and the brain at the time of injury are held responsible for the development of these aneurysms. Unlike these traumatic aneurysms, 29 ''spontaneous'' pericallosal aneurysms (3.2%) in adults were located at the bifurcations of the artery. As significantly fewer reports of traumatic aneurysms have been published during the last decade than before 1976, it is suggested that some might have been overlooked as a consequence of CT replacing cerebral angiography in the neuroradiological evaluation of severe head injury. This possibility should be kept in mind, especially when dealing with children after head injury and when CT scans indicate brain damage around the falx. The possibility of overlooking traumatic pericallosal aneurysms is described by other authors and discussed further in this paper. (orig.)

Fluid-Structure Simulations of a Ruptured Intracranial Aneurysm: Constant versus Patient-Specific Wall Thickness

Directory of Open Access Journals (Sweden)

S. Voß

2016-01-01

Full Text Available Computational Fluid Dynamics is intensively used to deepen the understanding of aneurysm growth and rupture in order to support physicians during therapy planning. However, numerous studies considering only the hemodynamics within the vessel lumen found no satisfactory criteria for rupture risk assessment. To improve available simulation models, the rigid vessel wall assumption has been discarded in this work and patient-specific wall thickness is considered within the simulation. For this purpose, a ruptured intracranial aneurysm was prepared ex vivo, followed by the acquisition of local wall thickness using μCT. The segmented inner and outer vessel surfaces served as solid domain for the fluid-structure interaction (FSI simulation. To compare wall stress distributions within the aneurysm wall and at the rupture site, FSI computations are repeated in a virtual model using a constant wall thickness approach. Although the wall stresses obtained by the two approaches—when averaged over the complete aneurysm sac—are in very good agreement, strong differences occur in their distribution. Accounting for the real wall thickness distribution, the rupture site exhibits much higher stress values compared to the configuration with constant wall thickness. The study reveals the importance of geometry reconstruction and accurate description of wall thickness in FSI simulations.

Sequential Hybrid Repair of Aorta and Bilateral Common Iliac Arteries Secondary to Chronic Aortic Dissection with Extensive Aneurysmal Degeneration in a Marfan Patient.

Science.gov (United States)

Hinojosa, Carlos A; Anaya-Ayala, Javier E; Laparra-Escareno, Hugo; Lizola, Rene; Torres-Machorro, Adriana

2017-09-01

Marfan syndrome is a connective tissue disorder associated with aortic dissection, aneurysmal degeneration and rupture. These cardiovascular complications represent the main cause of mortality, therefore repair is indicated. We present a 35-year-old woman who experienced acute onset of chest pain. Her imaging revealed a chronic DeBakey type I dissection with aortic root dilation and descending thoracic aneurysmal degeneration. She underwent a Bentall procedure and endovascular exclusion of the descending thoracic aortic aneurysm. She was closely followed and 2 years later a computed tomography angiography (CTA) revealed the aneurysmal degeneration of the thoracoabominal aorta and bilateral iliac arteries. The patient underwent a composite reconstruction using multi-visceral branched and bifurcated Dacron grafts. At 5 years from her last surgery, a CTA revealed no new dissection or further aneurysmal degenerations. Aortic disease in Marfan patients is a complex clinical problem that may lead to secondary or tertiary aortic reconstructions; close follow-up is mandatory.

Characterization of 3D printing techniques: Toward patient specific quality assurance spine-shaped phantom for stereotactic body radiation therapy.

Directory of Open Access Journals (Sweden)

Min-Joo Kim

Full Text Available Development and comparison of spine-shaped phantoms generated by two different 3D-printing technologies, digital light processing (DLP and Polyjet has been purposed to utilize in patient-specific quality assurance (QA of stereotactic body radiation treatment. The developed 3D-printed spine QA phantom consisted of an acrylic body phantom and a 3D-printed spine shaped object. DLP and Polyjet 3D printers using a high-density acrylic polymer were employed to produce spine-shaped phantoms based on CT images. Image fusion was performed to evaluate the reproducibility of our phantom, and the Hounsfield units (HUs were measured based on each CT image. Two different intensity-modulated radiotherapy plans based on both CT phantom image sets from the two printed spine-shaped phantoms with acrylic body phantoms were designed to deliver 16 Gy dose to the planning target volume (PTV and were compared for target coverage and normal organ-sparing. Image fusion demonstrated good reproducibility of the developed phantom. The HU values of the DLP- and Polyjet-printed spine vertebrae differed by 54.3 on average. The PTV Dmax dose for the DLP-generated phantom was about 1.488 Gy higher than that for the Polyjet-generated phantom. The organs at risk received a lower dose for the 3D printed spine-shaped phantom image using the DLP technique than for the phantom image using the Polyjet technique. Despite using the same material for printing the spine-shaped phantom, these phantoms generated by different 3D printing techniques, DLP and Polyjet, showed different HU values and these differently appearing HU values according to the printing technique could be an extra consideration for developing the 3D printed spine-shaped phantom depending on the patient's age and the density of the spinal bone. Therefore, the 3D printing technique and materials should be carefully chosen by taking into account the condition of the patient in order to accurately produce 3D printed

Characterization of 3D printing techniques: Toward patient specific quality assurance spine-shaped phantom for stereotactic body radiation therapy.

Science.gov (United States)

Kim, Min-Joo; Lee, Seu-Ran; Lee, Min-Young; Sohn, Jason W; Yun, Hyong Geon; Choi, Joon Yong; Jeon, Sang Won; Suh, Tae Suk

2017-01-01

Development and comparison of spine-shaped phantoms generated by two different 3D-printing technologies, digital light processing (DLP) and Polyjet has been purposed to utilize in patient-specific quality assurance (QA) of stereotactic body radiation treatment. The developed 3D-printed spine QA phantom consisted of an acrylic body phantom and a 3D-printed spine shaped object. DLP and Polyjet 3D printers using a high-density acrylic polymer were employed to produce spine-shaped phantoms based on CT images. Image fusion was performed to evaluate the reproducibility of our phantom, and the Hounsfield units (HUs) were measured based on each CT image. Two different intensity-modulated radiotherapy plans based on both CT phantom image sets from the two printed spine-shaped phantoms with acrylic body phantoms were designed to deliver 16 Gy dose to the planning target volume (PTV) and were compared for target coverage and normal organ-sparing. Image fusion demonstrated good reproducibility of the developed phantom. The HU values of the DLP- and Polyjet-printed spine vertebrae differed by 54.3 on average. The PTV Dmax dose for the DLP-generated phantom was about 1.488 Gy higher than that for the Polyjet-generated phantom. The organs at risk received a lower dose for the 3D printed spine-shaped phantom image using the DLP technique than for the phantom image using the Polyjet technique. Despite using the same material for printing the spine-shaped phantom, these phantoms generated by different 3D printing techniques, DLP and Polyjet, showed different HU values and these differently appearing HU values according to the printing technique could be an extra consideration for developing the 3D printed spine-shaped phantom depending on the patient's age and the density of the spinal bone. Therefore, the 3D printing technique and materials should be carefully chosen by taking into account the condition of the patient in order to accurately produce 3D printed patient-specific QA

Difference in aneurysm characteristics between patients with familial and sporadic aneurysmal subarachnoid haemorrhage

NARCIS (Netherlands)

Mensing, Liselore A.; Rinkel, Gabriel J E; Vlak, Monique H M; Van Der Schaaf, Irene C.; Ruigrok, Ynte M.

2016-01-01

Object Patients with familial intracranial aneurysms (IA) have a higher risk of rupture than patients with sporadic IA. We compared geometric and morphological risk factors for aneurysmal rupture between patients with familial and sporadic aneurysmal subarachnoid hemorrhage (aSAH) to analyse if

Clinical, morphological, and hemodynamic independent characteristic factors for rupture of posterior communicating artery aneurysms.

Science.gov (United States)

Zhang, Ying; Jing, Linkai; Liu, Jian; Li, Chuanhui; Fan, Jixing; Wang, Shengzhang; Li, Haiyun; Yang, Xinjian

2016-08-01

To identify clinical, morphological, and hemodynamic independent characteristic factors that discriminate posterior communicating artery (PCoA) aneurysm rupture status. 173 patients with single PCoA aneurysms (108 ruptured, 65 unruptured) between January 2012 and June 2014 were retrospectively collected. Patient-specific models based on their three-dimensional digital subtraction angiography images were constructed and analyzed by a computational fluid dynamic method. All variables were analyzed by univariate analysis and multivariate logistic regression analysis. Two clinical factors (younger age and atherosclerosis), three morphological factors (higher aspect ratio, bifurcation type, and irregular shape), and six hemodynamic factors (lower mean and minimum wall shear stress, higher oscillatory shear index, a greater portion of area under low wall shear stress, unstable and complex flow pattern) were significantly associated with PCoA aneurysm rupture. Independent factors characterizing the rupture status were identified as age (OR 0.956, p=0.015), irregular shape (OR 6.709, pPCoA aneurysm rupture were younger age, irregular shape, and low minimum wall shear stress. This may be useful for guiding risk assessments and subsequent treatment decisions for PCoA aneurysms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Sex differences in intracranial arterial bifurcations

DEFF Research Database (Denmark)

Lindekleiv, Haakon M; Valen-Sendstad, Kristian; Morgan, Michael K

2010-01-01

Subarachnoid hemorrhage (SAH) is a serious condition, occurring more frequently in females than in males. SAH is mainly caused by rupture of an intracranial aneurysm, which is formed by localized dilation of the intracranial arterial vessel wall, usually at the apex of the arterial bifurcation. T....... The female preponderance is usually explained by systemic factors (hormonal influences and intrinsic wall weakness); however, the uneven sex distribution of intracranial aneurysms suggests a possible physiologic factor-a local sex difference in the intracranial arteries....

Effects of Reynolds and Womersley Numbers on the Hemodynamics of Intracranial Aneurysms

Science.gov (United States)

Asgharzadeh, Hafez

2016-01-01

The effects of Reynolds and Womersley numbers on the hemodynamics of two simplified intracranial aneurysms (IAs), that is, sidewall and bifurcation IAs, and a patient-specific IA are investigated using computational fluid dynamics. For this purpose, we carried out three numerical experiments for each IA with various Reynolds (Re = 145.45 to 378.79) and Womersley (Wo = 7.4 to 9.96) numbers. Although the dominant flow feature, which is the vortex ring formation, is similar for all test cases here, the propagation of the vortex ring is controlled by both Re and Wo in both simplified IAs (bifurcation and sidewall) and the patient-specific IA. The location of the vortex ring in all tested IAs is shown to be proportional to Re/Wo2 which is in agreement with empirical formulations for the location of a vortex ring in a tank. In sidewall IAs, the oscillatory shear index is shown to increase with Wo and 1/Re because the vortex reached the distal wall later in the cycle (higher resident time). However, this trend was not observed in the bifurcation IA because the stresses were dominated by particle trapping structures, which were absent at low Re = 151.51 in contrast to higher Re = 378.79. PMID:27847544

Unruptured aneurysms with cranial nerve symptoms: efficacy of endosaccular guglielmi detachable coil treatment

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Joon; Kim, Dong Ik; Lee, Seung Koo; Kim, Si Yeon [Yonsei University College of Medicine, Seoul (Korea, Republic of)

2003-09-01

To evaluate the efficacy of endosaccular Guglielmi detachable coil (GDC) treatment of unruptured aneurysms causing cranial nerve (CN) symptoms. Among a database of 218 patients whose aneurysms were treated using GDC, seven patients met the criteria for unruptured aneurysms presenting with symptoms and signs of CN palsy. Changes in CN symptoms before and after GDC treatment were reviewed. Aneurysms were located in the internal carotid-posterior communicating artery (n=3), the basilar bifurcation (n=1) and the cavernous internal carotid artery (n=3). CN symptoms included ptosis (n=6), mydriasis (n=2), and extraocular muscle (EOM) disorder (CN III: n=4; CN VI: n=3). Overall, improvement or resolution of CN symptoms after treatment was noted in five patients. CN symptoms in cases involving small (10 mm) and intradural aneurysms tended to respond better to GDC treatment. Ptosis was the initial symptom to show improvement, while EOM dysfunction responded least favourably. GDC coil packing appears to be an appropriate treatment method for the relief of CN symptoms associated with intracranial aneurysms.

Unruptured aneurysms with cranial nerve symptoms: efficacy of endosaccular guglielmi detachable coil treatment

International Nuclear Information System (INIS)

Kim, Dong Joon; Kim, Dong Ik; Lee, Seung Koo; Kim, Si Yeon

2003-01-01

To evaluate the efficacy of endosaccular Guglielmi detachable coil (GDC) treatment of unruptured aneurysms causing cranial nerve (CN) symptoms. Among a database of 218 patients whose aneurysms were treated using GDC, seven patients met the criteria for unruptured aneurysms presenting with symptoms and signs of CN palsy. Changes in CN symptoms before and after GDC treatment were reviewed. Aneurysms were located in the internal carotid-posterior communicating artery (n=3), the basilar bifurcation (n=1) and the cavernous internal carotid artery (n=3). CN symptoms included ptosis (n=6), mydriasis (n=2), and extraocular muscle (EOM) disorder (CN III: n=4; CN VI: n=3). Overall, improvement or resolution of CN symptoms after treatment was noted in five patients. CN symptoms in cases involving small (10 mm) and intradural aneurysms tended to respond better to GDC treatment. Ptosis was the initial symptom to show improvement, while EOM dysfunction responded least favourably. GDC coil packing appears to be an appropriate treatment method for the relief of CN symptoms associated with intracranial aneurysms

CT findings of portal vein aneurysm

International Nuclear Information System (INIS)

Yang, Dal Mo; Chang, Mi Son; Yoon, Myung Hwan; Kim, Hak Soo; Kim, Hyung Sik; Chung, Hyo Sun; Chung, Jin Woo

1999-01-01

To describe the CT findings of portal vein aneurysm in eight patients. All patients included in this study (two men and six women) underwent CT examinations between October 1996 and June1998. Of these eight, three were suffering from hepatic disease and portal hypertension. We determined the location, shape, size, and characteristics of the lesions, and the presence or absence of portal vein anomaly. Seven patients had intrahepatic portal vein aneurysm (at the umbilical portion of the left portal vein in five patients, between the transverse and umbilical portion of the left portal vein in one, and at the bifurcation of the anterior and posterior branch of the right portal vein in one), while extrahepatic portal vein aneurysm, at the confluence of the superior mesenteric and splenic vein was found in only one. Lesions were cyst-shaped in seven cases and saccular in one, and showed well-circumscribed, markedly enhanced mass, which communicated with the portal vein and/or gives off major branches. Portal vein anomaly, in which the right anterior segmental portal vein originated from the umbilical portion of the left portal vein, was seen in three patients. In all three, intrahepatic portal vein aneurysm was present at the umbilical portion of the left portal vein, and in one, the umbilical protion of the left portal vein was located to the right of the Cantlic line. CT examination can help reveal portal vein aneurysm by detecting a well-circumscribed, markedly enhanced mass which communicates with the portal vein and/or gives off major branches

The Barrel vascular reconstruction device for endovascular coiling of wide-necked intracranial aneurysms: a multicenter, prospective, post-marketing study.

Science.gov (United States)

Gory, Benjamin; Blanc, Raphaël; Turjman, Francis; Berge, Jérôme; Piotin, Michel

2018-02-02

The Barrel vascular reconstruction device (Barrel VRD) is a novel stent with design features that allow endovascular coiling of wide-necked bifurcation aneurysms while preserving adjacent branches, without necessitating dual stent implantation. This study aimed to assess the safety and effectiveness of the Barrel VRD at 12-month follow-up. The Barrel VRD trial is a prospective, multicenter, observational post-marketing registry evaluating the use of the Barrel VRD for treatment of wide-necked bifurcation aneurysms. The primary effectiveness endpoint was successful aneurysm treatment measured by digital subtraction angiography with a Raymond-Roy occlusion grade of 1 or 2 in the absence of retreatment, parent artery stenosis (>50%), or target aneurysm rupture at 12 months. The primary safety endpoint was the absence of neurological death or major stroke at 12 months. Twenty patients were enrolled from December 2013 to December 2014. The device was implanted in 19 patients with 19 aneurysms (8 middle cerebral artery, 4 anterior communicating artery, 1 internal carotid artery terminus, 4 basilar artery aneurysms; mean dome height 5.7±1.91 mm; mean neck length 4.8±1.35 mm, mean dome-to-neck ratio 1.6±2.0). Coiling was performed in all cases. The primary effectiveness endpoint was achieved in 78.9% of subjects (15/19; 12 complete occlusions, 3 neck remnants), and the primary safety endpoint was 5.3% (1/19). This prospective study demonstrates that the Barrel VRD device resulted in ~80% occlusion rates and ~5% rates of neurological complications at 1 year after endovascular treatment of wide-necked bifurcation intracranial aneurysms. REGISTERED CLINICAL TRIAL: NCT02125097;Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Flow and wall shear stress characterization after endovascular aneurysm repair and endovascular aneurysm sealing in an infrarenal aneurysm model.

Science.gov (United States)

Boersen, Johannes T; Groot Jebbink, Erik; Versluis, Michel; Slump, Cornelis H; Ku, David N; de Vries, Jean-Paul P M; Reijnen, Michel M P J

2017-12-01

Endovascular aneurysm repair (EVAR) with a modular endograft has become the preferred treatment for abdominal aortic aneurysms. A novel concept is endovascular aneurysm sealing (EVAS), consisting of dual endoframes surrounded by polymer-filled endobags. This dual-lumen configuration is different from a bifurcation with a tapered trajectory of the flow lumen into the two limbs and may induce unfavorable flow conditions. These include low and oscillatory wall shear stress (WSS), linked to atherosclerosis, and high shear rates that may result in thrombosis. An in vitro study was performed to assess the impact of EVAR and EVAS on flow patterns and WSS. Four abdominal aortic aneurysm phantoms were constructed, including three stented models, to study the influence of the flow divider on flow (Endurant [Medtronic, Minneapolis, Minn], AFX [Endologix, Irvine, Calif], and Nellix [Endologix]). Experimental models were tested under physiologic resting conditions, and flow was visualized with laser particle imaging velocimetry, quantified by shear rate, WSS, and oscillatory shear index (OSI) in the suprarenal aorta, renal artery (RA), and common iliac artery. WSS and OSI were comparable for all models in the suprarenal aorta. The RA flow profile in the EVAR models was comparable to the control, but a region of lower WSS was observed on the caudal wall compared with the control. The EVAS model showed a stronger jet flow with a higher shear rate in some regions compared with the other models. Small regions of low WSS and high OSI were found near the distal end of all stents in the common iliac artery compared with the control. Maximum shear rates in each region of interest were well below the pathologic threshold for acute thrombosis. The different stent designs do not influence suprarenal flow. Lower WSS is observed in the caudal wall of the RA after EVAR and a higher shear rate after EVAS. All stented models have a small region of low WSS and high OSI near the distal outflow

Bilateral Distal Anterior Cerebral Artery Aneurysms Mimicking So-called "Kissing Aneurysms": A Case Report

OpenAIRE

山口, 竜一; 伊藤, 宣行; 前村, 栄治; 塩川, 芳昭; 齋藤, 勇; Ryuichi, YAMAGUCHI; Nobuyuki, ITO; Eiji, MAEMURA; Yoshiaki, SHIOKAWA; Isamu, SAITO; 公立阿伎留病院脳神経外科; 公立阿伎留病院脳神経外科; 公立阿伎留病院脳神経外科; 杏林大学医学部脳神経外科; 杏林大学医学部脳神経外科

2003-01-01

A 71-year-old woman presented disturbance of consciousness due to subarachnoid hemorrhage (SAH). A computed tomography (CT) on admission revealed diffuse thick SAH and intracerebral hematoma in the right frontal lobe. Conventional angiography and three-dimensional CT angiography showed symmetrical aneurysms located on the bilateral pericallosal arteries at bifurcation of the callosomarginal arteries. The operation was performed on the next day after onset of SAH. The aneurysms were clipped vi...

Treatment of ruptured intracranial aneurysms: implications of the ISAT on clipping versus coiling

International Nuclear Information System (INIS)

Berg, R. van den; Rinkel, G.J.E.; Vandertop, W.P.

2003-01-01

Patients with a ruptured intracranial aneurysm should be treated as soon as possible after the haemorrhage to prevent rebleeding and to allow vigorous treatment of ischemic events in case of vasospasm. The choice of treatment, endovascular or surgical, should be based on the angio-architectural aspects of the aneurysm. 3D rotational subtraction angiography will more clearly show the aneurysm morphology and will therefore help in the decision-making process. If an aneurysm is suitable for endovascular treatment ('coiling'), this should be the treatment of first choice, as has been clarified in the ISAT study. Location of the aneurysm only influences the treatment decision in aneurysms located at the basilar artery bifurcation. These aneurysms are preferably treated by endovascular means. The long-term results of endovascular and surgical treatment are still the subject of debate. For both treatment modalities, re-growth of the treated aneurysm has been described, but solid comparative data is missing. In analogy with the ISAT, referral of patients with a ruptured intracranial aneurysm should be performed as soon as possible after the haemorrhage. Preferably, this should be a hospital where neurosurgeons, interventional neuroradiologists, as well as neurologists (with expertise on medical treatment of patients with a subarachnoid haemorrhage) collaborate

Implantation of 3D-Printed Patient-Specific Aneurysm Models into Cadaveric Specimens: A New Training Paradigm to Allow for Improvements in Cerebrovascular Surgery and Research

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Arnau Benet

2015-01-01

Full Text Available Aim. To evaluate the feasibility of implanting 3D-printed brain aneurysm model in human cadavers and to assess their utility in neurosurgical research, complex case management/planning, and operative training. Methods. Two 3D-printed aneurysm models, basilar apex and middle cerebral artery, were generated and implanted in four cadaveric specimens. The aneurysms were implanted at the same anatomical region as the modeled patient. Pterional and orbitozygomatic approaches were done on each specimen. The aneurysm implant, manipulation capabilities, and surgical clipping were evaluated. Results. The 3D aneurysm models were successfully implanted to the cadaveric specimens’ arterial circulation in all cases. The features of the neck in terms of flexibility and its relationship with other arterial branches allowed for the practice of surgical maneuvering characteristic to aneurysm clipping. Furthermore, the relationship of the aneurysm dome with the surrounding structures allowed for better understanding of the aneurysmal local mass effect. Noticeably, all of these observations were done in a realistic environment provided by our customized embalming model for neurosurgical simulation. Conclusion. 3D aneurysms models implanted in cadaveric specimens may represent an untapped training method for replicating clip technique; for practicing certain approaches to aneurysms specific to a particular patient; and for improving neurosurgical research.

Appearance of femoropopliteal segment aneurysms in patients with abdominal aortic aneurysm

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Maksić Milanko

2012-01-01

Full Text Available Background/Aim. To promote better treatment outcome, as well as economic benefit it is very important to find out patients with simultaneous occurrence of both aortic and arterial aneurysms. The aim of this prospective study was to determine the frequency and factors affecting femoropopliteal (F-P segment aneurysms appearance in patients with abdominal aortic aneurysms (AAA. Methods. This study included 70 patients who had underwent elective or urgent surgery of AAA from January 1, 2006 to December 31, 2007. After ultrasonographic examination of F-P segment, all the patients were divided into two groups - those with adjunctive F-P segment aneurysm (n = 20 and the group of 50 patients with no adjunctive F-P segment aneurysm. In both groups demographic characteristics (gender, age, risk factors (diabetes mellitus, elevated serum levels of cholesterol and triglycerides, arterial hypertension, smoking, obesity and cardiovascular comorbidity (cerebrovascular desease, ischemic heart desease were investigated. Results. Twenty (28.57% patients who had been operated on because of AAA, had adjunctive aneurysmal desease of F-P segment. Diabetes was no statistically significantly more present among the patients who, beside AAA, had adjunctive aneurismal desease of F-P segment (χ2 = 0.04; DF = 1; p > 0.05. Also, in both groups there was no statistically significant difference in gender structure (χ2 = 2. 05; DF = 2; p > 0.05, age (χ2 = 5. 46; DF = 1; p > 0.05, total cholesterol level (χ2 = 0.89; DF = 1; p > 0.05 and triglyceride (χ2 = 0.89; DF = 1; p > 0.05 levels, the presence of arterial hypertension (χ2 = 1.38; DF = 2; p > 0.05, smoking (χ2 = 1.74; DF = 1; p > 0.05, obesity (χ2 = 1.76; DF = 1; p > 0.05 and presence of cerebrovascular desease (χ2 = 2.34; DF = 1; p > 0.05. Conversly, ischemic heart desease was statistically significantly more present among the patients who, beside AAA, had adjunctive aneurismal desease of F-P segment (χ2 = 5

PIV-measured versus CFD-predicted flow dynamics in anatomically realistic cerebral aneurysm models.

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Ford, Matthew D; Nikolov, Hristo N; Milner, Jaques S; Lownie, Stephen P; Demont, Edwin M; Kalata, Wojciech; Loth, Francis; Holdsworth, David W; Steinman, David A

2008-04-01

Computational fluid dynamics (CFD) modeling of nominally patient-specific cerebral aneurysms is increasingly being used as a research tool to further understand the development, prognosis, and treatment of brain aneurysms. We have previously developed virtual angiography to indirectly validate CFD-predicted gross flow dynamics against the routinely acquired digital subtraction angiograms. Toward a more direct validation, here we compare detailed, CFD-predicted velocity fields against those measured using particle imaging velocimetry (PIV). Two anatomically realistic flow-through phantoms, one a giant internal carotid artery (ICA) aneurysm and the other a basilar artery (BA) tip aneurysm, were constructed of a clear silicone elastomer. The phantoms were placed within a computer-controlled flow loop, programed with representative flow rate waveforms. PIV images were collected on several anterior-posterior (AP) and lateral (LAT) planes. CFD simulations were then carried out using a well-validated, in-house solver, based on micro-CT reconstructions of the geometries of the flow-through phantoms and inlet/outlet boundary conditions derived from flow rates measured during the PIV experiments. PIV and CFD results from the central AP plane of the ICA aneurysm showed a large stable vortex throughout the cardiac cycle. Complex vortex dynamics, captured by PIV and CFD, persisted throughout the cardiac cycle on the central LAT plane. Velocity vector fields showed good overall agreement. For the BA, aneurysm agreement was more compelling, with both PIV and CFD similarly resolving the dynamics of counter-rotating vortices on both AP and LAT planes. Despite the imposition of periodic flow boundary conditions for the CFD simulations, cycle-to-cycle fluctuations were evident in the BA aneurysm simulations, which agreed well, in terms of both amplitudes and spatial distributions, with cycle-to-cycle fluctuations measured by PIV in the same geometry. The overall good agreement

Safety and Efficacy of Aneurysm Treatment with the WEB

DEFF Research Database (Denmark)

Pierot, L; Gubucz, I; Buhk, J H

2017-01-01

BACKGROUND AND PURPOSE: Flow disruption with the Woven EndoBridge (WEB) device is an innovative technique for the endovascular treatment of wide-neck bifurcation aneurysms. The initial version of the device (WEB Double-Layer) was evaluated in the WEB Clinical Assessment of IntraSaccular Aneurysm ...

Ex vivo repair of renal artery aneurysm associated with surgical treatment of abdominal aortic aneurysm

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Kostić Dušan M.

2004-01-01

Full Text Available INTRODUCTION Renal artery aneurysms is relatively uncommon with reported incidence ranges from 0.3% to 1%. However, considering all visceral artery aneurysms the percentage of renal artery aneurysms is relatively high between 15-25%. The distal forms of renal artery aneurysms sometimes require "ex vivo" reconstruction and kidney autotransplantation. CASE REPORT A 75-year-old male presented with the right abdominal and back pain. He suffered from a long history of arterial hypertension and chronic renal failure over the last few months (urea blood = 19.8 mmol/l; creatinine = 198 mmol/l. Duplex ultrasonography showed abdominal aortic aneurysm. Subsequent translumbarangiography revealed juxtarenal abdominal aortic aneurysm associated with distal right renal artery aneurysm. The operation was performed under combined thoracic epidural analgesia and general anesthesia using transperitoneal approach. After the laparotomy, the ascending colon was mobilized and reflected medially followed by Kocher maneuver. The result was visualization of the anterior aspect of the right kidney, the collecting system, ureter as well as the right renal vein and artery with large saccular aneurysm located distally. After mobilization of the renal vessels and careful dissection of the ureter, the kidney was explanted. The operation was continued by two surgical teams. The first team performed abdominal aortic aneurysm resection and reconstruction with bifurcated Dacron graft. The second team performed ex vivo reparation of renal artery aneurysm. All time during the explantation, the kidney was perfused by Collins' solution. The saccular right renal artery aneurysm 4 cm in diameter was located at the kidney hilus at the first bifurcation. Three branches originated from the aneurysm. The aneurysm was resected completely. The longest and widest of three branches arising from the aneurysmal sac was end-to-end anastomized with 6 mm PTFE graft. After this intervention, one of

Aneurysm occlusion in elderly patients with aneurysmal subarachnoid haemorrhage : a cost-utility analysis

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Koffijberg, H.; Buskens, E.; Rinkel, G. J. E.

Background Aneurysm occlusion after subarachnoid haemorrhage (SAH) aims to improve outcome by reducing the rebleeding risk. With increasing age, overall prognosis decreases, and the complications of aneurysm occlusion increase. The balance of risks for aneurysm occlusion in elderly SAH patients in

Arterial Ligation for Infected Femoral Psuedo-Aneurysm in Drug Injecting Abusers

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Mohammadzade Mohammad Ali

2009-10-01

Full Text Available Pseudo-aneurysm of the femoral artery is the most common arterial complication in drug injecting abusers. Scholars in vascular surgery have published debating statements regarding techniques of successful surgical management during last two decades. We present the results of simple arterial ligation in a series of 32 patients presenting with infected femoral pseudo-aneurysm. Most of the patients were males (89%. Young persons in the age group of 15-44 years were mostly affected. Site of lesion included common femoral artery in 65% , superficial femoral artery 28% and at bifurcation 6.2%. celulitis in 14 (53%, abscess & "ncelulitis in 6 (19%, necrosing fasciitis in 2 (6.2% and vascular abscess in 7 (22% cases were the forms of associated local infection. There was no hemorrhage, vascular thrombosis, amputation, or mortality. Claudicating were the only complications identified in 2 patients with Tripe ligation. Ligation is the optimal management for infected pseudo-aneurysms because it is easy, cost-effective, and safe. Early reconstruction is not recommended, since there is an extended infection in the location of the pseudo-aneurysm.

Endovascular Treatment of Infrarenal Abdominal Aortic Aneurysm with Short and Angulated Neck in High-Risk Patient

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Stylianos Koutsias

2013-01-01

Full Text Available Endovascular treatment of abdominal aortic aneurysms (AAA is an established alternative to open repair. However lifelong surveillance is still required to monitor endograft function and signal the need for secondary interventions (Hobo and Buth 2006. Aortic morphology, especially related to the proximal neck, often complicates the procedure or increases the risk for late device-related complications (Hobo et al. 2007 and Chisci et al. 2009. The definition of a short and angulated neck is based on length (60° (Hobo et al. 2007 and Chisci et al. 2009. A challenging neck also offers difficulties during open repairs (OR, necessitating extensive dissection with juxta- or suprarenal aortic cross-clamping. Patients with extensive aneurysmal disease typically have more comorbidities and may not tolerate extensive surgical trauma (Sarac et al. 2002. It is, therefore, unclear whether aneurysms with a challenging proximal neck should be offered EVAR or OR (Cox et al. 2006, Choke et al. 2006, Robbins et al. 2005, Sternbergh III et al. 2002, Dillavou et al. 2003, and Greenberg et al. 2003. In our case the insertion of a thoracic endograft followed by the placement of a bifurcated aortic endograft for the treatment of a very short and severely angulated neck proved to be feasible offering acceptable duration of aneurysm exclusion. This adds up to our armamentarium in the treatment of high-risk patients, and it should be considered in emergency cases when the fenestrated and branched endografts are not available.

Simple or Complex Stenting for Bifurcation Coronary Lesions: A Patient-Level Pooled-Analysis of the Nordic Bifurcation Study and the British Bifurcation Coronary Study

DEFF Research Database (Denmark)

Behan, Miles W; Holm, Niels Ramsing; Curzen, Nicholas P

2011-01-01

Background— Controversy persists regarding the correct strategy for bifurcation lesions. Therefore, we combined the patient-level data from 2 large trials with similar methodology: the NORDIC Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study (BBC ONE). Methods and Results— B...

Onyx combined with coiling embolization for endovascular treatment of complex intracranial ruptured aneurysms

International Nuclear Information System (INIS)

Wu Yongfa; Huang Qinghai; Yang Pengfei; Zhang Lei; Li Qiang; Liu Jianmin

2011-01-01

Objective: To study the therapeutic effect of Onyx combined with stent-assisted coiling in embolizing complex intracranial ruptured aneurysms. Methods: Onyx combined with stent-assisted coiling embolization was conducted in two patients with complex intracranial ruptured aneurysms. The clinical data were retrospectively analyzed. The related literature concerning intracranial complex aneurysm treated with Onyx was reviewed. Results: Two intracranial complex aneurysms were embolized with Onyx together with coils. The lesions were located at internal carotid arterial bifurcation (n=1) and at the anterior wall of internal carotid artery (n=1). Complete embolization of the aneurysms was achieved immediately after the procedure while the parent arteries remained patent. Conclusion: For the treatment of complex intracranial ruptured aneurysms Onyx combined with coiling embolization is safe, effective and feasible. This technique can improve the degree of embolization. To make the evaluation of the long-term efficacy further study is needed. (authors)

Assessing patient dose in interventional fluoroscopy using patient-dependent hybrid phantoms

Science.gov (United States)

Johnson, Perry Barnett

Interventional fluoroscopy uses ionizing radiation to guide small instruments through blood vessels or other body pathways to sites of clinical interest. The technique represents a tremendous advantage over invasive surgical procedures, as it requires only a small incision, thus reducing the risk of infection and providing for shorter recovery times. The growing use and increasing complexity of interventional procedures, however, has resulted in public health concerns regarding radiation exposures, particularly with respect to localized skin dose. Tracking and documenting patient-specific skin and internal organ dose has been specifically identified for interventional fluoroscopy where extended irradiation times, multiple projections, and repeat procedures can lead to some of the largest doses encountered in radiology. Furthermore, inprocedure knowledge of localized skin doses can be of significant clinical importance to managing patient risk and in training radiology residents. In this dissertation, a framework is presented for monitoring the radiation dose delivered to patients undergoing interventional procedures. The framework is built around two key points, developing better anthropomorphic models, and designing clinically relevant software systems for dose estimation. To begin, a library of 50 hybrid patient-dependent computational phantoms was developed based on the UF hybrid male and female reference phantoms. These phantoms represent a different type of anthropomorphic model whereby anthropometric parameters from an individual patient are used during phantom selection. The patient-dependent library was first validated and then used in two patient-phantom matching studies focused on cumulative organ and local skin dose. In terms of organ dose, patient-phantom matching was shown most beneficial for estimating the dose to large patients where error associated with soft tissue attenuation differences could be minimized. For small patients, inherent difference

Endovascular Aortic Aneurysm Repair for Abdominal Aortic Aneurysm: Single Center Experience in 122 Patients

International Nuclear Information System (INIS)

Lee, Yun Young; Song, Jang Hyeon; Kim, Yong Tae; Yim, Nam Yeol; Kim, Jae Kyu; Lee, Ho Kyun; Choi, Soo Jin Na; Chung, Sang Young; Kim, Soo Hyun; Chang, Nam Kyu

2013-01-01

To analyze a single center experience of endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms. Results of 122 patients who underwent EVAR were analyzed, retrospectively. Sex, age, aneurysmal morphology, hostile neck anatomy, preprocedural and postprocedural sac-diameter, technical and clinical success, postprocedural complication and need of additional procedure were analyzed. A total of 111 male and 11 female patients were included. Morphology of the aneurysms was as follows: fusiform (n = 108), saccular (n = 3) and ruptured type (n = 11). Sixty-four patients had hostile neck anatomy. The preprocedural mean sac-diameter was 52.4 mm. Postprocedural sac-diameter was decreased or stable in 110 patients (90.2%) and increased in 8 patients (6.6%). Technical success rate was 100% and clinical success rate was 86.1%. Fifty-one patients showed endoleak (41.8%) and 15 patients (12.3%) underwent secondary intervention due to type I endoleak (n = 4), type II endoleak (n = 4) and stent-graft thrombosis (n = 7). EVAR is a safe and effective therapy for abdominal aortic aneurysm, and it has high technical success and clinical success rate, and low complication rate.

SU-F-BRE-04: Construction of 3D Printed Patient Specific Phantoms for Dosimetric Verification Measurements

International Nuclear Information System (INIS)

Ehler, E; Higgins, P; Dusenbery, K

2014-01-01

Purpose: To validate a method to create per patient phantoms for dosimetric verification measurements. Methods: Using a RANDO phantom as a substitute for an actual patient, a model of the external features of the head and neck region of the phantom was created. A phantom was used instead of a human for two reasons: to allow for dosimetric measurements that would not be possible in-vivo and to avoid patient privacy issues. Using acrylonitrile butadiene styrene thermoplastic as the building material, a hollow replica was created using the 3D printer filled with a custom tissue equivalent mixture of paraffin wax, magnesium oxide, and calcium carbonate. A traditional parallel-opposed head and neck plan was constructed. Measurements were performed with thermoluminescent dosimeters in both the RANDO phantom and in the 3D printed phantom. Calculated and measured dose was compared at 17 points phantoms including regions in high and low dose regions and at the field edges. On-board cone beam CT was used to localize both phantoms within 1mm and 1° prior to radiation. Results: The maximum difference in calculated dose between phantoms was 1.8% of the planned dose (180 cGy). The mean difference between calculated and measured dose in the anthropomorphic phantom and the 3D printed phantom was 1.9% ± 2.8% and −0.1% ± 4.9%, respectively. The difference between measured and calculated dose was determined in the RANDO and 3D printed phantoms. The differences between measured and calculated dose in each respective phantom was within 2% for 12 of 17 points. The overlap of the RANDO and 3D printed phantom was 0.956 (Jaccard Index). Conclusion: A custom phantom was created using a 3D printer. Dosimetric calculations and measurements showed good agreement between the dose in the RANDO phantom (patient substitute) and the 3D printed phantom

SU-F-BRE-04: Construction of 3D Printed Patient Specific Phantoms for Dosimetric Verification Measurements

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Ehler, E; Higgins, P; Dusenbery, K [University of Minnesota, Minneapolis, MN (United States)

2014-06-15

Purpose: To validate a method to create per patient phantoms for dosimetric verification measurements. Methods: Using a RANDO phantom as a substitute for an actual patient, a model of the external features of the head and neck region of the phantom was created. A phantom was used instead of a human for two reasons: to allow for dosimetric measurements that would not be possible in-vivo and to avoid patient privacy issues. Using acrylonitrile butadiene styrene thermoplastic as the building material, a hollow replica was created using the 3D printer filled with a custom tissue equivalent mixture of paraffin wax, magnesium oxide, and calcium carbonate. A traditional parallel-opposed head and neck plan was constructed. Measurements were performed with thermoluminescent dosimeters in both the RANDO phantom and in the 3D printed phantom. Calculated and measured dose was compared at 17 points phantoms including regions in high and low dose regions and at the field edges. On-board cone beam CT was used to localize both phantoms within 1mm and 1° prior to radiation. Results: The maximum difference in calculated dose between phantoms was 1.8% of the planned dose (180 cGy). The mean difference between calculated and measured dose in the anthropomorphic phantom and the 3D printed phantom was 1.9% ± 2.8% and −0.1% ± 4.9%, respectively. The difference between measured and calculated dose was determined in the RANDO and 3D printed phantoms. The differences between measured and calculated dose in each respective phantom was within 2% for 12 of 17 points. The overlap of the RANDO and 3D printed phantom was 0.956 (Jaccard Index). Conclusion: A custom phantom was created using a 3D printer. Dosimetric calculations and measurements showed good agreement between the dose in the RANDO phantom (patient substitute) and the 3D printed phantom.

Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations.

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Tse, Kwong Ming; Chiu, Peixuan; Lee, Heow Pueh; Ho, Pei

2011-03-15

Aortic dissecting aneurysm is one of the most catastrophic cardiovascular emergencies that carries high mortality. It was pointed out from clinical observations that the aneurysm development is likely to be related to the hemodynamics condition of the dissected aorta. In order to gain more insight on the formation and progression of dissecting aneurysm, hemodynamic parameters including flow pattern, velocity distribution, aortic wall pressure and shear stress, which are difficult to measure in vivo, are evaluated using numerical simulations. Pulsatile blood flow in patient-specific dissecting aneurismal aortas before and after the formation of lumenal aneurysm (pre-aneurysm and post-aneurysm) is investigated by computational fluid dynamics (CFD) simulations. Realistic time-dependent boundary conditions are prescribed at various arteries of the complete aorta models. This study suggests the helical development of false lumen around true lumen may be related to the helical nature of hemodynamic flow in aorta. Narrowing of the aorta is responsible for the massive recirculation in the poststenosis region in the lumenal aneurysm development. High pressure difference of 0.21 kPa between true and false lumens in the pre-aneurismal aorta infers the possible lumenal aneurysm site in the descending aorta. It is also found that relatively high time-averaged wall shear stress (in the range of 4-8 kPa) may be associated with tear initiation and propagation. CFD modeling assists in medical planning by providing blood flow patterns, wall pressure and wall shear stress. This helps to understand various phenomena in the development of dissecting aneurysm. Copyright © 2011 Elsevier Ltd. All rights reserved.

Endovascular repair of para-anastomotic aortoiliac aneurysms.

LENUS (Irish Health Repository)

Tsang, Julian S

2009-11-01

The purpose of this study is to evaluate the use of endovascular stent grafts in the treatment of para-anastomotic aneurysms (PAAs) as an alternative to high-risk open surgical repair. We identified all patients with previous open aortic aneurysm repair who underwent infrarenal endovascular aneurysm repair (EVAR) at our institution from June 1998 to April 2007. Patient demographics, previous surgery, and operative complications were recorded. One hundred forty-eight patients underwent EVAR during the study period and 11 patients had previous aortic surgery. Of these 11 redo patients, the mean age was 62 years at initial surgery and 71 years at EVAR. All patients were male. Initial open repair was for rupture in five (45%) patients. The average time between initial and subsequent reintervention was 9 years. All patients were ASA Grade III or IV. Fifty-five percent of the PAAs involved the iliac arteries, 36% the abdominal aorta, and 9% were aortoiliac. Ten patients had endovascular stent-grafts inserted electively, and one patient presented with a contained leak. Aorto-uni-iliac stent-grafts were deployed in seven patients, and bifurcated stent-grafts in four patients. A 100% successful deployment rate was achieved. Perioperative mortality was not seen and one patient needed surgical reintervention to correct an endoleak. Endovascular repair of PAAs is safe and feasible. It is a suitable alternative and has probably now become the treatment of choice in the management of PAAs.

Factors associated with outcomes in ruptured aneurysmal patients: Clinical Study of 80 Patients

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Alfotih Gobran Taha Ahmed

2015-03-01

Full Text Available Background: Due to insufficient data in the literature, the optimal timing for surgical intervention for ruptured intracranial aneurysms is still controversial. Some practitioners advocate early surgery, but others not. It is important to identify other factors that can be used to predict poor prognosis in ruptured intracranial aneurysm patients. Objective: To determine the influence of timing of clipping surgery, and other factors on the outcomes of ruptured intracranial aneurysms in Hunt & Hess I~III grade patients. Method: We have performed a retrospective study involving 80 patients who were surgically treated for ruptured intracranial aneurysm between 2007 and 2012. The patient population consisted of 50(62.5% females and 30(37.5% males, with an age range of 12 to 75 years old, mean age 52.33 ± 10.63 years. We measured association between the Glasgow Outcome Scores and Sex, timing of clipping surgery, aneurysm location and pre-operative patient's neurological condition using famous Hunt and Hess grade system. Results: We did not find any correlation between the outcomes of ruptured intracranial aneurysm patients and timing (early, intermediate, late stage of clipping, sex, aneurysm location. Whereas there is a significant correlation between patients outcomes and pre-operative patient neurological condition (Hunt & Hess grade. Conclusion: Timing of Surgery (early, intermediate, late does not affect outcomes in low Hunt and Hess grade patients I~III. Whereas neurological condition (Hunt & Hess has strong impact on postoperative outcomes. Others factors like sex, Age, Aneurysm location have no effect on outcomes in ruptured intracranial aneurysms.

Retrospective analysis of the prevalence of asymptomatic cerebral aneurysm in 4518 patients undergoing magnetic resonance angiography. When does cerebral aneurysm develop?

International Nuclear Information System (INIS)

Horikoshi, Toru; Yamagata, Zentaro; Nukui, Hideaki; Akiyama, Iwao

2002-01-01

The natural history of cerebral aneurysms was investigated by measuring the prevalence of incidentally found unruptured aneurysms in the general population and evaluating the characteristics including risk factors. 'De novo' formation of aneurysm was also demographically estimated. The prevalence of incidental aneurysm was evaluated among 4518 patients who underwent magnetic resonance (MR) angiography for various reasons in a neurosurgical institute. Double the number of patients were randomly selected from the remaining patients without aneurysm as the Control group so that sex and age group were matched to the Aneurysm group. One hundred twenty seven patients (2.8%) had diagnoses of aneurysm. The prevalence of asymptomatic aneurysm among middle-aged and elderly patients were predominant in women and increased with age in both sexes. Patients with aneurysms had significantly more hypertension and family history of subarachnoid hemorrhage compared to the controls. The prevalence was markedly increased in the 8th decade in men and the 7th decade in women, and new aneurysms seemed to develop predominantly around these decades. Cerebral aneurysms become detectable on MR angiography in the middle or later decades, and women tend to develop aneurysm earlier than men. Hypertension and family history of subarachnoid hemorrhage are probably risk factors for the development of aneurysm. (author)

Early aneurysmal degeneration of femoral vein conduit used for aortoiliac reconstruction in a child

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Zakariyae Bouziane, MD

2016-09-01

Full Text Available We report the case of a 14-year-old boy who underwent an aortobi-iliac bypass with a femoral vein graft. The patient presented with early aneurysmal degeneration of the entire venous graft only 11 months later. He was treated successfully with redo abdominal aortic surgery and a bifurcated Dacron graft.

Endovascular repair of abdominal aortic aneurysms: vascular anatomy, device selection, procedure, and procedure-specific complications.

Science.gov (United States)

Bryce, Yolanda; Rogoff, Philip; Romanelli, Donald; Reichle, Ralph

2015-01-01

Abdominal aortic aneurysm (AAA) is abnormal dilatation of the aorta, carrying a substantial risk of rupture and thereby marked risk of death. Open repair of AAA involves lengthy surgery time, anesthesia, and substantial recovery time. Endovascular aneurysm repair (EVAR) provides a safer option for patients with advanced age and pulmonary, cardiac, and renal dysfunction. Successful endovascular repair of AAA depends on correct selection of patients (on the basis of their vascular anatomy), choice of the correct endoprosthesis, and familiarity with the technique and procedure-specific complications. The type of aneurysm is defined by its location with respect to the renal arteries, whether it is a true or false aneurysm, and whether the common iliac arteries are involved. Vascular anatomy can be divided more technically into aortic neck, aortic aneurysm, pelvic perfusion, and iliac morphology, with grades of difficulty with respect to EVAR, aortic neck morphology being the most common factor to affect EVAR appropriateness. When choosing among the devices available on the market, one must consider the patient's vascular anatomy and choose between devices that provide suprarenal fixation versus those that provide infrarenal fixation. A successful technique can be divided into preprocedural imaging, ancillary procedures before AAA stent-graft placement, the procedure itself, postprocedural medical therapy, and postprocedural imaging surveillance. Imaging surveillance is important in assessing complications such as limb thrombosis, endoleaks, graft migration, enlargement of the aneurysm sac, and rupture. Last, one must consider the issue of radiation safety with regard to EVAR. (©)RSNA, 2015.

Emergency Endovascular Treatment of Abdominal Aortic Aneurysms: Feasibility and Results

International Nuclear Information System (INIS)

Lagana, Domenico; Carrafiello, Gianpaolo; Mangini, Monica; Fontana, Federico; Caronno, Roberto; Castelli, Patrizio; Cuffari, Salvatore; Fugazzola, Carlo

2006-01-01

Purpose. To assess the feasibility and effectiveness of emergency endovascular treatment of abdominal aortic aneurysms (AAAs). Methods. During 36 months we treated, on an emergency basis, 30 AAAs with endovascular exclusion. In 21 hemodynamically stable patients preoperative CT angiography (CTA) was performed to confirm the diagnosis and to plan the treatment; 9 patients with hemorrhagic shock were evaluated with angiography performed in the operating room. Twenty-two Excluder (Gore) and 8 Zenith (Cook) stent-grafts (25 bifurcated and 5 aorto-uni-iliac) were used. The follow-up was performed by CTA at 1, 3, 6, and 12 months. Results. Technical success was achieved in 100% of cases with a 10% mortality rate. The total complication rate was 23% (5 increases in serum creatinine level and 2 wound infections). During the follow-up, performed in 27 patients (1-36 months, mean 15.2 months), 4 secondary endoleaks (15%) (3 type II, 2 spontaneously thrombosed and 1 under observation, and 1 type III treated by iliac extender insertion) and 1 iliac leg occlusion (treated with femoro-femoral bypass) occurred. We observed a shrinkage of the aneurysmal sac in 8 of 27 cases and stability in 19 of 27 cases; we did not observe any endotension. Conclusions. Endovascular repair is a good option for emergency treatment of AAAs. The team's experience allows correct planning of the procedure in emergency situations also, with technical results comparable with elective repair. In our experience the bifurcated stent-graft is the device of choice in patients with suitable anatomy because the procedure is less time-consuming than aorto-uni-iliac stent-grafting with surgical crossover, allowing faster aneurysm exclusion. However, further studies are required to demonstrate the long-term efficacy of endovascular repair compared with surgical treatment

Effects of Intraluminal Thrombus on Patient-Specific Abdominal Aortic Aneurysm Hemodynamics via Stereoscopic Particle Image Velocity and Computational Fluid Dynamics Modeling

Science.gov (United States)

Chen, Chia-Yuan; Antón, Raúl; Hung, Ming-yang; Menon, Prahlad; Finol, Ender A.; Pekkan, Kerem

2014-01-01

The pathology of the human abdominal aortic aneurysm (AAA) and its relationship to the later complication of intraluminal thrombus (ILT) formation remains unclear. The hemodynamics in the diseased abdominal aorta are hypothesized to be a key contributor to the formation and growth of ILT. The objective of this investigation is to establish a reliable 3D flow visualization method with corresponding validation tests with high confidence in order to provide insight into the basic hemodynamic features for a better understanding of hemodynamics in AAA pathology and seek potential treatment for AAA diseases. A stereoscopic particle image velocity (PIV) experiment was conducted using transparent patient-specific experimental AAA models (with and without ILT) at three axial planes. Results show that before ILT formation, a 3D vortex was generated in the AAA phantom. This geometry-related vortex was not observed after the formation of ILT, indicating its possible role in the subsequent appearance of ILT in this patient. It may indicate that a longer residence time of recirculated blood flow in the aortic lumen due to this vortex caused sufficient shear-induced platelet activation to develop ILT and maintain uniform flow conditions. Additionally, two computational fluid dynamics (CFD) modeling codes (Fluent and an in-house cardiovascular CFD code) were compared with the two-dimensional, three-component velocity stereoscopic PIV data. Results showed that correlation coefficients of the out-of-plane velocity data between PIV and both CFD methods are greater than 0.85, demonstrating good quantitative agreement. The stereoscopic PIV study can be utilized as test case templates for ongoing efforts in cardiovascular CFD solver development. Likewise, it is envisaged that the patient-specific data may provide a benchmark for further studying hemodynamics of actual AAA, ILT, and their convolution effects under physiological conditions for clinical applications. PMID:24316984

The diagnostic value of three-dimensional dynamic contrast-enhanced MR angiography for intracranial aneurysms

International Nuclear Information System (INIS)

Liu Qi; Lu Jianping; Wang Fei; Wang Li; Tian Jianming; Jin Aiguo; Zeng Hao

2003-01-01

Objective: To assess the clinical value of three-dimensional dynamic contrast-enhanced MR angiography (3D DCE-MRA) in the detection for intracranial aneurysm. Methods: 3D DCE-MRA was performed in 54 patients highly suspected with intracranial aneurysms. Then conventional digital subtraction angiography (DSA) and feasible endovascular treatment were performed simultaneously. A three-dimensional fast imaging with steady state precession (3D FISP) was used for 3D DCE-MRA(Gd-DTPA dose, 0.2 mmol per kilogram for body weight; acquisition time, 10 seconds). The source images were subtracted from mask images and transferred to computer workstation. All images were subsequently post-processed using three-dimensional reconstruction. 3D DCE-MRA images and DSA images were compared for demonstration of the aneurysm, its neck, and relationship with parent artery, and the usefulness for endovascular treatment was evaluated. Results: There were 39 cases with 45 intracranial aneurysms. The sensitivity, specificity, and accuracy of 3D DCE-MRA were 96%, 73% and 90%, respectively. Aneurysm and its neck depiction at 3D DCE-MRA was significantly better than that at DSA, especially for aneurysms adjacent to the cavernous sinus and near the PICA of vertebral artery. 3D DEC-MRA could guide neurosurgeons to the desired DSA projection, and helped them make plan for interventional or surgical treatment in advance. But the diagnosis should be very carefully made for small aneurysms located in the periphery and the arterial bifurcation. Conclusion: 3D DEC-MRA is a fast, noninvasive and efficient technique for diagnosing intracranial aneurysms. Its three dimensional information is helpful for DSA demonstration and treatment planning. Any uncertain diagnosis requires DSA confirmation

Treatment of a Common Iliac Aneurysm by Endovascular Exclusion Using the Amplatzer Vascular Plug and Femorofemoral Crossover Graft

International Nuclear Information System (INIS)

Coupe, Nicholas J.; Ling, Lynn; Cowling, Mark G.; Asquith, John R.; Hopkinson, Gregory B.

2009-01-01

We report our initial experience using the Amplatzer Vascular Plug II (AVP2) in the treatment of a left common iliac aneurysm. Following investigation by computerized tomographic angiography and catheter angiography, a 79-year-old man was found to have a markedly tortuous iliac system, with a left common iliac artery aneurysm that measured 48 mm in maximal diameter. Due to the patient's age and comorbidities the surgical opinion was that conventional open repair was not suitable. However, due to the tortuous nature of the aneurysm and iliac vessels, standard endovascular repair, using either a bifurcated or an aorto-uni-iliac stent graft, was also not possible. A combined approach was used by embolizing the ipsilateral internal iliac artery using coils and excluding the aneurysm using two AVP2 occlusion devices, followed by femorofemoral crossover grafting. Total aneurysm occlusion was achieved using this method and this allowed the patient to have a much less invasive surgical procedure than with conventional open repair of common iliac aneurysms, thus avoiding potential comorbidity and mortality.

Microsurgical clipping of ophthalmic artery aneurysms: surgical results and visual outcomes with 208 aneurysms.

Science.gov (United States)

Kamide, Tomoya; Tabani, Halima; Safaee, Michael M; Burkhardt, Jan-Karl; Lawton, Michael T

2018-01-26

OBJECTIVE While most paraclinoid aneurysms can be clipped with excellent results, new postoperative visual deficits are a concern. New technology, including flow diverters, has increased the popularity of endovascular therapy. However, endovascular treatment of paraclinoid aneurysms is not without procedural risks, is associated with higher rates of incomplete aneurysm occlusion and recurrence, and may not address optic nerve compression symptoms that surgical debulking can. The increasing endovascular management of paraclinoid aneurysms should be justified by comparisons to surgical benchmarks. The authors, therefore, undertook this study to define patient, visual, and aneurysm outcomes in the most common type of paraclinoid aneurysm: ophthalmic artery (OphA) aneurysms. METHODS Results from microsurgical clipping of 208 OphA aneurysms in 198 patients were retrospectively reviewed. Patient demographics, aneurysm morphology (size, calcification, etc.), clinical characteristics, and patient outcomes were recorded and analyzed. RESULTS Despite 20% of these aneurysms being large or giant in size, complete aneurysm occlusion was accomplished in 91% of 208 cases, with OphA patency preserved in 99.5%. The aneurysm recurrence rate was 3.1% and the retreatment rate was 0%. Good outcomes (modified Rankin Scale score 0-2) were observed in 96.2% of patients overall and in all 156 patients with unruptured aneurysms. New visual field defects (hemianopsia or quadrantanopsia) were observed in 8 patients (3.8%), decreased visual acuity in 5 (2.4%), and monocular blindness in 9 (4.3%). Vision improved in 9 (52.9%) of the 17 patients with preoperative visual deficits. CONCLUSIONS The most important risk associated with clipping OphA aneurysms is a new visual deficit. Meticulous microsurgical technique is necessary during anterior clinoidectomy, aneurysm dissection, and clip application to optimize visual outcomes, and aggressive medical management postoperatively might potentially

Endovascular Aortic Aneurysm Repair with the Talent Stent-Graft: Outcomes in Patients with Large Iliac Arteries

International Nuclear Information System (INIS)

England, Andrew; Butterfield, John S.; McCollum, Charles N.; Ashleigh, Raymond J.

2008-01-01

The purpose of this study is to report outcomes following endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) in patients with ectatic common iliac arteries (CIAs). Of 117 AAA patients treated by EVAR between 1998 and 2005, 87 (74%) had CIAs diameters 18 but <25 mm. All patients were treated with Talent stent-grafts, 114 bifurcated and 3 AUI devices. Departmental databases and patient records were reviewed to assess outcomes. Technical success, iliac-related outcome, and iliac-related reintervention (IRSI) were analyzed. Patients with EVAR extending into the external iliac artery were excluded. Median (range) follow-up for the study group was 24 (1-84) months. Initial technical success was 98% for CIAs <18 mm and 100% for CIAs ≥18 mm (p = 0.551). There were three distal type I endoleaks (two in the ectatic group) and six iliac limb occlusions (one in an ectatic patient); there were no statistically significant differences between groups (p = 0.4). There were nine IRSIs (three stent-graft extensions, six femorofemoral crossover grafts); three of these patients had one or both CIAs ≥18 mm (p = 0.232). One-year freedom from IRSI was 92% ± 3% and 84% ± 9% for the <18-mm and ≥18-mm CIA groups, respectively (p = 0.232). We conclude that the treatment of AAA by EVAR in patients with CIAs 18-24 mm appears to be safe and effective, however, it may be associated with more frequent reinterventions.

Treatment of intracranial wide neck aneurysm with neuroform self-expanding stent combined with spring coils

International Nuclear Information System (INIS)

Bai Weixing; Jiang Xifeng; Li Tianxiao; Zhai Shuiting; Xue Jiangyu; Wang Ziliang; Cao Huicun

2008-01-01

Objective: To evaluate the preliminary experience of the combined self-expanding neurovascular stent (Neuroform stent) with detachable coils in the management of intracranial wide neck aneurysms. Methods: Self-expanding neurovascular stents with detachable coils were used in treating 27 intracranial wide neck aneurysms of 25 patients including cavernous segment ICA aneurysms in 3, ophthalmic arterial anemysm in 1, PcomA in 18, AcomA in 2, MCAM1 in 1, MCA bifurcation in 1, and basilar trunk in 1. Among them, 2 cases consisted of multi-aneurysms, 2 aneurysms coincide with absolute wide neck (> 4 mm) and 6 with comparatively wide neck (> 7 mm). Nemoform stents were deployed across the neck of aneurysm and detachable coils were released to embolize the aneurysm through stent mesh. Results: Twenty-six Neuroform stents were successfully deployed in 25 patients including 4 Neuroform II stents, and 22 Neurofom III stents(all combined with spring coils). Total occlusion was achieved in 7 patients with residual neck in 9 nearly complete occlusion and partial occlusion in 11. 2 patients were rebleeding and other 2 showed intra-stent thrombosis during the operations. The latter 2 included 1 with post-operative limb paraplegia and 1 died. Still another 1 had transient ischemic attack after the operation. Twenty-three patient recovered well. Twenty-four patients were under clinical followed up from 0.5 to 28 months with an average of 10.8 months. There was no bleeding. Three patients were angiographically followed up for 3-6 months after the procedure, with only 1 case of in-stent thrombosis and no change in other 2 aneurysms with neck remnant. Conclusions: The Neuroform stent is technically feasible and safe for treating intracranial wide neck aneurysms unsuitable for clipping because of its prevention for coil protruding into parent artery. The long term effect still need to be further investigated. (authors)

The Effect of Hemodynamics on Cerebral Aneurysm Morphology

Science.gov (United States)

Metcalfe, Ralph; Mantha, Aishwarya; Karmonik, Christof; Strother, Charles

2004-11-01

One of the difficulties in applying principles of hemodynamics to the study of blood flow in aneurysms are the drastic variations in possible shape of both the aneurysms and the parent arteries in the region of interest. We have taken data from three para-opthalmic internal carotid artery aneurysms using 3D-digital subtraction angiography (3D-DSA) and performed CFD simulations of steady and unsteady flows through the three different cases using the same pressure gradients and pulsatile flow waveforms (based on the Ku model for flow through the Carotid bifurcation). We have found that the total pressure differential within the aneurysms is consistent with the direction of flow, and that the dynamic pressure gradient within the aneurysm is very small compared with the static pressure variations. Wall shear stresses were highest near regions of sharp arterial curvature, but always remained low inside the aneurysm. These results suggest a more complex role for hemodynamics in aneurysm generation, growth and rupture.

Epidemiological study of 183 patients with spontaneous rupture of cerebral aneurysm

International Nuclear Information System (INIS)

Antonova, D.; Tasheva, E.

2015-01-01

Cerebral vessels aneurysms represent a significant part of the cerebral vessels pathology. There is no extensive study on that in Bulgaria. We present a study of 183 patients with spontaneous rupture of cerebral aneurysm, diagnosed and treated in UMHATEM ‘Pirogov’, Sofia. We used clinical methods - data from subject history, analysis of the accompanying documentation, subject medical chart; imaging-diagnostics methods - CT, DSA and MRI; and statistical methods. A total of 183 patients with ruptured intracranial aneurysms were studied. 65% were females and 35% were men.The ration female/male is 1.86, The mean age of all patients is 53.1 ±10.1 years. The highest incidence of ruptured aneurysms is seen in the age group 50 to 59 years. Aneurysms of a. cerebri media and a. communicants anterior are the most frequent (63.4% in total); while the lest are those of a basilaris (4.9%). 88.5% of the aneurysms in the studied group are small, 9.8% are large and 1.6% are giant. Intracranial hematomas are seen in 13.1% of the patients with ruptured aneurysms. Most frequently hematomas are connected with a. cerebri media and a.communicants anterior (87.5% in total). Patients with multiple aneurysms are 11.5% in total, 85.7% of them with an aneurysm of a.cerebri media. The incidence of ruptured cerebral aneurysms is higher amongst female. Frequency in the fifth decade of life is the highest. Most often seen are the aneurysms of a. cerebri media and a. communicants anterior, and the least - those of a. basilaris. Intracranial hematomas most frequently are associated with ruptures of a. cerebri media and a. communicants anterior, in patients with multiple aneurysms the highest is the frequency of aneurysms of a. cerebri media. (authors)

Development of age-specific Japanese physical phantoms for dose evaluation in infant CT examinations

International Nuclear Information System (INIS)

Yamauchi-Kawaura, C.; Fujii, K.; Imai, K.; Ikeda, M.; Akahane, K.; Obara, S.; Yamauchi, M.; Narai, K.; Katsu, T.

2016-01-01

Secondary to the previous development of age-specific Japanese head phantoms, the authors designed Japanese torso phantoms for dose assessment in infant computed tomography (CT) examinations and completed a Japanese 3-y-old head-torso phantom. For design of age-specific torso phantoms (0, 0.5, 1 and 3 y old), anatomical structures were measured from CT images of Japanese infant patients. From the CT morphometry, it was found that rib cages of Japanese infants were smaller than those in Europeans and Americans. Radiophotoluminescence glass dosemeters were used for dose measurement of a 3-y-old head-torso phantom. To examine the validity of the developed phantom, organ and effective doses by the in-phantom dosimetry system were compared with simulation values in a web-based CT dose calculation system (WAZA-ARI). The differences in doses between the two systems were <20 % at the doses of organs within scan regions and effective doses in head, chest and abdomino-pelvic CT examinations. (authors)

Advanced 3D Mesh Manipulation in Stereolithographic Files and Post-Print Processing for the Manufacturing of Patient-Specific Vascular Flow Phantoms.

Science.gov (United States)

O'Hara, Ryan P; Chand, Arpita; Vidiyala, Sowmya; Arechavala, Stacie M; Mitsouras, Dimitrios; Rudin, Stephen; Ionita, Ciprian N

2016-02-27

Complex vascular anatomies can cause the failure of image-guided endovascular procedures. 3D printed patient-specific vascular phantoms provide clinicians and medical device companies the ability to preemptively plan surgical treatments, test the likelihood of device success, and determine potential operative setbacks. This research aims to present advanced mesh manipulation techniques of stereolithographic (STL) files segmented from medical imaging and post-print surface optimization to match physiological vascular flow resistance. For phantom design, we developed three mesh manipulation techniques. The first method allows outlet 3D mesh manipulations to merge superfluous vessels into a single junction, decreasing the number of flow outlets and making it feasible to include smaller vessels. Next we introduced Boolean operations to eliminate the need to manually merge mesh layers and eliminate errors of mesh self-intersections that previously occurred. Finally we optimize support addition to preserve the patient anatomical geometry. For post-print surface optimization, we investigated various solutions and methods to remove support material and smooth the inner vessel surface. Solutions of chloroform, alcohol and sodium hydroxide were used to process various phantoms and hydraulic resistance was measured and compared with values reported in literature. The newly mesh manipulation methods decrease the phantom design time by 30 - 80% and allow for rapid development of accurate vascular models. We have created 3D printed vascular models with vessel diameters less than 0.5 mm. The methods presented in this work could lead to shorter design time for patient specific phantoms and better physiological simulations.

Individual radiation therapy patient whole-body phantoms for peripheral dose evaluations: method and specific software

International Nuclear Information System (INIS)

Alziar, I; Vicente, C; Giordana, G; Ben-Harrath, O; De Vathaire, F; Diallo, I; Bonniaud, G; Couanet, D; Chavaudra, J; Lefkopoulos, D; Ruaud, J B; Diaz, J C; Grandjean, P; Kafrouni, H

2009-01-01

This study presents a method aimed at creating radiotherapy (RT) patient-adjustable whole-body phantoms to permit retrospective and prospective peripheral dose evaluations for enhanced patient radioprotection. Our strategy involves virtual whole-body patient models (WBPM) in different RT treatment positions for both genders and for different age groups. It includes a software tool designed to match the anatomy of the phantoms with the anatomy of the actual patients, based on the quality of patient data available. The procedure for adjusting a WBPM to patient morphology includes typical dimensions available in basic auxological tables for the French population. Adjustment is semi-automatic. Because of the complexity of the human anatomy, skilled personnel are required to validate changes made in the phantom anatomy. This research is part of a global project aimed at proposing appropriate methods and software tools capable of reconstituting the anatomy and dose evaluations in the entire body of RT patients in an adapted treatment planning system (TPS). The graphic user interface is that of a TPS adapted to obtain a comfortable working process. Such WBPM have been used to supplement patient therapy planning images, usually restricted to regions involved in treatment. Here we report, as an example, the case of a patient treated for prostate cancer whose therapy planning images were complemented by an anatomy model. Although present results are preliminary and our research is ongoing, they appear encouraging, since such patient-adjusted phantoms are crucial in the optimization of radiation protection of patients and for follow-up studies. (note)

Individual radiation therapy patient whole-body phantoms for peripheral dose evaluations: method and specific software.

Science.gov (United States)

Alziar, I; Bonniaud, G; Couanet, D; Ruaud, J B; Vicente, C; Giordana, G; Ben-Harrath, O; Diaz, J C; Grandjean, P; Kafrouni, H; Chavaudra, J; Lefkopoulos, D; de Vathaire, F; Diallo, I

2009-09-07

This study presents a method aimed at creating radiotherapy (RT) patient-adjustable whole-body phantoms to permit retrospective and prospective peripheral dose evaluations for enhanced patient radioprotection. Our strategy involves virtual whole-body patient models (WBPM) in different RT treatment positions for both genders and for different age groups. It includes a software tool designed to match the anatomy of the phantoms with the anatomy of the actual patients, based on the quality of patient data available. The procedure for adjusting a WBPM to patient morphology includes typical dimensions available in basic auxological tables for the French population. Adjustment is semi-automatic. Because of the complexity of the human anatomy, skilled personnel are required to validate changes made in the phantom anatomy. This research is part of a global project aimed at proposing appropriate methods and software tools capable of reconstituting the anatomy and dose evaluations in the entire body of RT patients in an adapted treatment planning system (TPS). The graphic user interface is that of a TPS adapted to obtain a comfortable working process. Such WBPM have been used to supplement patient therapy planning images, usually restricted to regions involved in treatment. Here we report, as an example, the case of a patient treated for prostate cancer whose therapy planning images were complemented by an anatomy model. Although present results are preliminary and our research is ongoing, they appear encouraging, since such patient-adjusted phantoms are crucial in the optimization of radiation protection of patients and for follow-up studies.

SU-G-BRB-01: A Novel 3D Printed Patient-Specific Phantom for Spine SBRT Quality Assurance: Comparison of 3D Printing Techniques

Energy Technology Data Exchange (ETDEWEB)

Lee, S; Kim, M; Lee, M; Suh, T [Research Institute of Biomedical Engineering, The Catholic University of Korea, Seoul (Korea, Republic of); Department of Biomedical Engineering, The Catholic University of Korea, Seoul (Korea, Republic of)

2016-06-15

Purpose: The novel 3 dimensional (3D)-printed spine quality assurance (QA) phantoms generated by two different 3D-printing technologies, digital light processing (DLP) and Polyjet, were developed and evaluated for spine stereotactic body radiation treatment (SBRT). Methods: The developed 3D-printed spine QA phantom consisted of an acrylic body and a 3D-printed spine phantom. DLP and Polyjet 3D printers using the high-density acrylic polymer were employed to produce spine-shaped phantoms based on CT images. To verify dosimetric effects, the novel phantom was made it enable to insert films between each slabs of acrylic body phantom. Also, for measuring internal dose of spine, 3D-printed spine phantom was designed as divided laterally exactly in half. Image fusion was performed to evaluate the reproducibility of our phantom, and the Hounsfield unit (HU) was measured based on each CT image. Intensity-modulated radiotherapy plans to deliver a fraction of a 16 Gy dose to a planning target volume (PTV) based on the two 3D-printing techniques were compared for target coverage and normal organ-sparing. Results: Image fusion demonstrated good reproducibility of the fabricated spine QA phantom. The HU values of the DLP- and Polyjet-printed spine vertebrae differed by 54.3 on average. The PTV Dmax dose for the DLP-generated phantom was about 1.488 Gy higher than for the Polyjet-generated phantom. The organs at risk received a lower dose when the DLP technique was used than when the Polyjet technique was used. Conclusion: This study confirmed that a novel 3D-printed phantom mimicking a high-density organ can be created based on CT images, and that a developed 3D-printed spine phantom could be utilized in patient-specific QA for SBRT. Despite using the same main material, DLP and Polyjet yielded different HU values. Therefore, the printing technique and materials must be carefully chosen in order to accurately produce a patient-specific QA phantom.

SU-G-BRB-01: A Novel 3D Printed Patient-Specific Phantom for Spine SBRT Quality Assurance: Comparison of 3D Printing Techniques

International Nuclear Information System (INIS)

Lee, S; Kim, M; Lee, M; Suh, T

2016-01-01

Purpose: The novel 3 dimensional (3D)-printed spine quality assurance (QA) phantoms generated by two different 3D-printing technologies, digital light processing (DLP) and Polyjet, were developed and evaluated for spine stereotactic body radiation treatment (SBRT). Methods: The developed 3D-printed spine QA phantom consisted of an acrylic body and a 3D-printed spine phantom. DLP and Polyjet 3D printers using the high-density acrylic polymer were employed to produce spine-shaped phantoms based on CT images. To verify dosimetric effects, the novel phantom was made it enable to insert films between each slabs of acrylic body phantom. Also, for measuring internal dose of spine, 3D-printed spine phantom was designed as divided laterally exactly in half. Image fusion was performed to evaluate the reproducibility of our phantom, and the Hounsfield unit (HU) was measured based on each CT image. Intensity-modulated radiotherapy plans to deliver a fraction of a 16 Gy dose to a planning target volume (PTV) based on the two 3D-printing techniques were compared for target coverage and normal organ-sparing. Results: Image fusion demonstrated good reproducibility of the fabricated spine QA phantom. The HU values of the DLP- and Polyjet-printed spine vertebrae differed by 54.3 on average. The PTV Dmax dose for the DLP-generated phantom was about 1.488 Gy higher than for the Polyjet-generated phantom. The organs at risk received a lower dose when the DLP technique was used than when the Polyjet technique was used. Conclusion: This study confirmed that a novel 3D-printed phantom mimicking a high-density organ can be created based on CT images, and that a developed 3D-printed spine phantom could be utilized in patient-specific QA for SBRT. Despite using the same main material, DLP and Polyjet yielded different HU values. Therefore, the printing technique and materials must be carefully chosen in order to accurately produce a patient-specific QA phantom.

A Monte Carlo-based method to estimate radiation dose from spiral CT: from phantom testing to patient-specific models

International Nuclear Information System (INIS)

Jarry, G; De Marco, J J; Beifuss, U; Cagnon, C H; McNitt-Gray, M F

2003-01-01

The purpose of this work is to develop and test a method to estimate the relative and absolute absorbed radiation dose from axial and spiral CT scans using a Monte Carlo approach. Initial testing was done in phantoms and preliminary results were obtained from a standard mathematical anthropomorphic model (MIRD V) and voxelized patient data. To accomplish this we have modified a general purpose Monte Carlo transport code (MCNP4B) to simulate the CT x-ray source and movement, and then to calculate absorbed radiation dose in desired objects. The movement of the source in either axial or spiral modes was modelled explicitly while the CT system components were modelled using published information about x-ray spectra as well as information provided by the manufacturer. Simulations were performed for single axial scans using the head and body computed tomography dose index (CTDI) polymethylmethacrylate phantoms at both central and peripheral positions for all available beam energies and slice thicknesses. For comparison, corresponding physical measurements of CTDI in phantom were made with an ion chamber. To obtain absolute dose values, simulations and measurements were performed in air at the scanner isocentre for each beam energy. To extend the verification, the CT scanner model was applied to the MIRD V model and compared with published results using similar technical factors. After verification of the model, the generalized source was simulated and applied to voxelized models of patient anatomy. The simulated and measured absolute dose data in phantom agreed to within 2% for the head phantom and within 4% for the body phantom at 120 and 140 kVp; this extends to 8% for the head and 9% for the body phantom across all available beam energies and positions. For the head phantom, the simulated and measured absolute dose data agree to within 2% across all slice thicknesses at 120 kVp. Our results in the MIRD phantom agree within 11% of all the different organ dose values

Brain aneurysm patients seen in Harare, Zimbabwe: cases review ...

African Journals Online (AJOL)

Setting: Parirenyatwa Group of Hospitals and Avenues Clinic, Harare, Zimbabwe. Subjects: Adult intracranial aneurysm patients. Interventions: Craniotomy and aneurysm clipping. Results: Seventeen patients were seen during the period of study. Twelve were female patients while five were male with a male to female ratio ...

Influence of hemodynamic factors on rupture of intracranial aneurysms: patient-specific 3D mirror aneurysms model computational fluid dynamics simulation.

Science.gov (United States)

Lu, G; Huang, L; Zhang, X L; Wang, S Z; Hong, Y; Hu, Z; Geng, D Y

2011-08-01

Hemodynamics factors play an important role in the rupture of cerebral aneurysms. The purpose of this study was to evaluate the impact of hemodynamic factors on the rupture of the MANs with 3D reconstruction model CFD simulation. RDSA was performed in 9 pairs of intracranial MANs. Each pair was divided into ruptured and unruptured groups. The hemodynamic factors of the aneurysms and their parent arteries were compared. There was a significant difference in the WSS at peak systole between the regions of the aneurysms and their parent arteries in the ruptured group (ie, 6.49 ± 3.48 Pa versus 8.78 ± 3.57 Pa, P =.015) but not in the unruptured group (ie, 9.80 ± 4.12 Pa versus 10.17 ± 7.48 Pa, P =.678). The proportion of the low WSS area to the whole area of the aneurysms was 12.20 ± 18.08% in the ruptured group and 3.96 ± 6.91% in the unruptured group; the difference between the 2 groups was statistically significant (P =.015). The OSI was 0.0879 ± 0.0764 in the ruptured group, which was significantly higher than that of the unruptured group (ie, 0.0183 ± 0.0191, P =.008). MANs may be a useful disease model to investigate possible causes linked to ruptured aneurysms. The ruptured aneurysms manifested lower WSS compared with their parent arteries, a higher proportion of the low WSS area to the whole area of aneurysm, and higher OSI compared with the unruptured aneurysms.

Endo-luminal grafting for treatment of abdominal aortic aneurysms

International Nuclear Information System (INIS)

Fu Weiguo; Wang Yuqi; Chen Fuzhen; Ye Jianrong; Wang Jianhua; Yan Zhiping; Cheng Jiemin

2000-01-01

Objective: To evaluate the preliminary clinical results of endovascular procedures for abdominal aortic aneurysms (AAA) in a prospective study. Methods: Six patients (average age 70 years, range 56 to 78) with infrarenal AAA were enrolled in Shanghai Zhongshan hospital from February 1998 to February 1999. Computed tomography and angiography were done in every patient for measurement of the length, diameter, and angulation of the proximal and distal AAA necks, aneurysm sac, and common and external iliac arteries. The average diameter of the aneurysm was 6.3 cm (range 4.6 cm to 8.0 cm). The mean proximal neck diameter was 2.0 cm (range 1.8 cm to 2.2 cm) and proximal neck length was 3.0 cm (range 2.5 cm to 3.5 cm). All patients were treated with the endo-luminal grafting for exclusion of AAA. Results: Two tubular and 4 bifurcated endo-grafts were used. All endo-graft procedures were completed successfully. One patient died of renal failure 72 hours after the procedure because of the prolonged operative time and excessive contrast medium. Aortography after the procedure showed the AAA were excluded by endo-graft and no endo-leak in the proximal or distal connections was detected. The patients could take meal and were ambulatory on the first and second postoperative day, respectively. Clinical success (aneurysm exclusion with no death or endo-leak) at 30 days was 83.3%. In the 24 months follow-up in 5 cases, no migration, endo-leak, and increasing aneurysm size were detected with spiral CT or color Duplex ultrasound. Conclusion: Based on initial results and a short term mean follow-up period of 24 months, the endovascular treatment of AAA with stent-graft system is feasible and safe. Further study will be required to observe the long term result in the exclusion of AAA

Analysis of Surgical Freedom Variation Across the Basilar Artery Bifurcation: Towards a Deeper Insight Into Approach Selection for Basilar Apex Aneurysms.

Science.gov (United States)

Tayebi Meybodi, Ali; Benet, Arnau; Rodriguez Rubio, Roberto; Yousef, Sonia; Lawton, Michael T

2018-03-03

The orbitozygomatic approach is generally advocated over the pterional approach for basilar apex aneurysms. However, the impact of the extensions of the pterional approach on the obtained maneuverability over multiple vascular targets (relevant to basilar apex surgery) has not been studied before. To analyze the patterns of surgical freedom change across the basilar bifurcation between the pterional, orbitopterional, and orbitozygomatic approaches. Surgical freedom was assessed for 3 vascular targets important in basilar apex aneurysm surgery (ipsilateral and contralateral P1-P2 junctions, and basilar apex), and compared between the pterional, orbitopterional, and orbitozygomatic approaches in 10 cadaveric specimens. Transitioning from the pterional to orbitopterional approach, the surgical freedom increased significantly at all 3 targets (P < .05). However, the gain in surgical freedom declined progressively from the most superficial target (60% for ipsilateral P1-P2 junction) to the deepest target (35% for contralateral P1-P2 junction). Conversely, transitioning from the orbitopterional to the orbitozygomatic approach, the gain in surgical freedom was minimal for the ipsilateral P1-P2 and basilar apex (<4%), but increased dramatically to 19% at the contralateral P1-P2 junction. The orbitopterional approach provides a remarkable increase in surgical maneuverability compared to the pterional approach for the basilar apex target and the relevant adjacent arterial targets. However, compared to the orbitopterional, the orbitozygomatic approach adds little maneuverability except for the deepest target (ie, contralateral P1-P2 junction). Therefore, the orbitozygomatic approach may be most efficacious with larger basilar apex aneurysms limiting the control over of the contralateral P1 PCA.

SU-C-213-01: 3D Printed Patient Specific Phantom Composed of Bone and Soft Tissue Substitute Plastics for Radiation Therapy

International Nuclear Information System (INIS)

Ehler, E; Sterling, D; Higgins, P

2015-01-01

Purpose: 3D printed phantoms constructed of multiple tissue approximating materials could be useful in both clinical and research aspects of radiotherapy. This work describes a 3D printed phantom constructed with tissue substitute plastics for both bone and soft tissue; air cavities were included as well. Methods: 3D models of an anonymized nasopharynx patient were generated for air cavities, soft tissues, and bone, which were segmented by Hounsfield Unit (HU) thresholds. HU thresholds were chosen to define air-to-soft tissue boundaries of 0.65 g/cc and soft tissue-to-bone boundaries of 1.18 g/cc based on clinical HU to density tables. After evaluation of several composite plastics, a bone tissue substitute was identified as an acceptable material for typical radiotherapy x-ray energies, composed of iron and PLA plastic. PET plastic was determined to be an acceptable soft tissue substitute. 3D printing was performed on a consumer grade dual extrusion fused deposition model 3D printer. Results: MVCT scans of the 3D printed heterogeneous phantom were acquired. Rigid image registration of the patient and the 3D printed phantom scans was performed. The average physical density of the soft tissue and bone regions was 1.02 ± 0.08 g/cc and 1.39 ± 0.14 g/cc, respectively, for the patient kVCT scan. In the 3D printed phantom MVCT scan, the average density of the soft tissue and bone was 1.01 ± 0.09 g/cc and 1.44 ± 0.12 g/cc, respectively. Conclusion: A patient specific phantom, constructed of heterogeneous tissue substitute materials was constructed by 3D printing. MVCT of the 3D printed phantom showed realistic tissue densities were recreated by the 3D printing materials. Funding provided by intra-department grant by University of Minnesota Department of Radiation Oncology

SU-C-213-01: 3D Printed Patient Specific Phantom Composed of Bone and Soft Tissue Substitute Plastics for Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

Ehler, E; Sterling, D; Higgins, P [University of Minnesota, Minneapolis, MN (United States)

2015-06-15

Purpose: 3D printed phantoms constructed of multiple tissue approximating materials could be useful in both clinical and research aspects of radiotherapy. This work describes a 3D printed phantom constructed with tissue substitute plastics for both bone and soft tissue; air cavities were included as well. Methods: 3D models of an anonymized nasopharynx patient were generated for air cavities, soft tissues, and bone, which were segmented by Hounsfield Unit (HU) thresholds. HU thresholds were chosen to define air-to-soft tissue boundaries of 0.65 g/cc and soft tissue-to-bone boundaries of 1.18 g/cc based on clinical HU to density tables. After evaluation of several composite plastics, a bone tissue substitute was identified as an acceptable material for typical radiotherapy x-ray energies, composed of iron and PLA plastic. PET plastic was determined to be an acceptable soft tissue substitute. 3D printing was performed on a consumer grade dual extrusion fused deposition model 3D printer. Results: MVCT scans of the 3D printed heterogeneous phantom were acquired. Rigid image registration of the patient and the 3D printed phantom scans was performed. The average physical density of the soft tissue and bone regions was 1.02 ± 0.08 g/cc and 1.39 ± 0.14 g/cc, respectively, for the patient kVCT scan. In the 3D printed phantom MVCT scan, the average density of the soft tissue and bone was 1.01 ± 0.09 g/cc and 1.44 ± 0.12 g/cc, respectively. Conclusion: A patient specific phantom, constructed of heterogeneous tissue substitute materials was constructed by 3D printing. MVCT of the 3D printed phantom showed realistic tissue densities were recreated by the 3D printing materials. Funding provided by intra-department grant by University of Minnesota Department of Radiation Oncology.

Polycystic kidney disease among 4,436 intracranial aneurysm patients from a defined population.

Science.gov (United States)

Nurmonen, Heidi J; Huttunen, Terhi; Huttunen, Jukka; Kurki, Mitja I; Helin, Katariina; Koivisto, Timo; von Und Zu Fraunberg, Mikael; Jääskeläinen, Juha E; Lindgren, Antti E

2017-10-31

To define the association of autosomal dominant polycystic kidney disease (ADPKD) with the characteristics of aneurysmal subarachnoid hemorrhage (aSAH) and unruptured intracranial aneurysm (IA) disease. We fused data from the Kuopio Intracranial Aneurysm database (n = 4,436 IA patients) and Finnish nationwide registries into a population-based series of 53 IA patients with ADPKD to compare the aneurysm- and patient-specific characteristics of IA disease in ADPKD and in the general IA population, and to identify risks for de novo IA formation. In total, there were 33 patients with ADPKD with aSAH and 20 patients with ADPKD with unruptured IAs. The median size of ruptured IAs in ADPKD was significantly smaller than in the general population (6.00 vs 8.00 mm) and the proportion of small ruptured IAs was significantly higher (31% vs 18%). Median age at aSAH was 42.8 years, 10 years younger than in the general IA population. Multiple IAs were present in 45% of patients with ADPKD compared to 28% in the general IA population. Cumulative risk of de novo IA formation was 1.3% per patient-year (vs 0.2% in the general IA population). Hazard for de novo aneurysm formation was significantly elevated in patients with ADPKD (Cox regression hazard ratio 7.7, 95% confidence interval 2.8-20; p IAs in patients with ADPKD and risk for de novo IAs is higher than in the general Eastern Finnish population. ADPKD should be considered as an indicator for long-term angiographic follow-up in patients with diagnosed IAs. © 2017 American Academy of Neurology.

Aortocaval fistula (ACF) in patients operated for ruptured aortic aneurysm (rAAA)

DEFF Research Database (Denmark)

Warning, Karina; Houlind, Kim Christian; Ravn, Hans

Aortocaval fistula (ACF) in patients operated for Ruptured Acute Aorta Aneurysm (rAAA): A surgical challenge. Introduction Aortocaval fistula is a rare complication of abdominal aortic aneurysm (AAA). It been reported to be present in less than 1% of all AAAs. ACF arise in patients with large...... aneurysms and is typically discovered peroperatively in patients with rAAA. Open surgical treatment is associated with high mortality and morbidity. ACF is a result of spontaneously rupture of large atherosclerotic aneurysms into the inferior vena cava in 80%, 15% arise after trauma and 5% are iatrogenic....... Patients During the last 9 month, we have operated three cases with rAAA and ACF. All patients had an open, acute operation. All ACFs detected during operation. Common for all operations was that the patients had large aneurysms (>10 cm) and extensive bleeding (3-4 l) immediately when the aneurysm...

Risk of abdominal aortic aneurysm (AAA) among male and female relatives of AAA patients.

Science.gov (United States)

van de Luijtgaarden, Koen M; Rouwet, Ellen V; Hoeks, Sanne E; Stolker, Robert J; Verhagen, Hence Jm; Majoor-Krakauer, Danielle

2017-04-01

Sex affects the presentation, treatment, and outcomes of abdominal aortic aneurysm (AAA). Although AAAs are less prevalent in women, at least in the general population, women with an AAA have a poorer prognosis in comparison to men. Sex differences in the genetic predisposition for aneurysm disease remain to be established. In this study we investigated the familial risk of AAA for women compared to men. All living AAA patients included in a 2004-2012 prospective database were invited to the multidisciplinary vascular/genetics outpatient clinic between 2009 and 2012 for assessment of family history using detailed questionnaires. AAA risk for male and female relatives was calculated separately and stratified by sex of the AAA patients. Families of 568 AAA patients were investigated and 22.5% of the patients had at least one affected relative. Female relatives had a 2.8-fold and male relatives had a 1.7-fold higher risk than the estimated sex-specific population risk. Relatives of female AAA patients had a higher aneurysm risk than relatives of male patients (9.0 vs 5.9%, p = 0.022), corresponding to 5.5- and 2.0-fold increases in aneurysm risk in the female and male relatives, respectively. The risk for aortic aneurysm in relatives of AAA patients is higher than expected from population risk. The excess risk is highest for the female relatives of AAA patients and for the relatives of female AAA patients. These findings endorse targeted AAA family screening for female and male relatives of all AAA patients.

Natural history and surgical results in patients with unruptured intracranial aneurysms

International Nuclear Information System (INIS)

Okiyama, Koichi; Nagano, Osamu; Machida, Toshio; Serizawa, Toru; Ono, Junichi; Higuchi, Yoshinori

2008-01-01

The management of patients with unruptured intracranial aneurysms (UIAs) is controversial. We aimed to assess the natural history of UIAs and evaluate the surgical results. We analyzed 154 patients (181 saccular UIAs) with no history of subarachnoid hemorrhage (SAH) from a different aneurysm. Aneurysms were detected by magnetic resonance angiography (MRA) or by 3-dimensional CT angiography. Although the most frequent reason for the diagnosis was routine brain examinations of healthy patients or a vague symptom such as headache or dizziness, 15 patients were symptomatic. The natural history in patients who did not have surgery (follow-up group: 76 cases, 95 aneurysms) was assessed, and the surgical outcome of UIAs (surgical group: 78 cases, 86 aneurysms) was evaluated. Among 76 patients in the follow-up group, 7 had SAH. The mean latency period to aneurysm rupture was 3.2 months. The aneurysms with subsequent bleeding ranged from 5 to 25 mm (19.3 mm on average), whereas those without ranged from 1 to 28 mm (4.5 mm on average). The rupture rates of UIAs in anterior and posterior circulation were 6.2% and 14.3%, respectively. All ruptured cases were females. Mortality and morbidity associated with UIAs in the follow-up group were 3.9% and 3.9%, respectively. In the surgical group, no mortality was noted. Permanent morbidity associated with prospective repair of UIAs was 5.1%, although the morbidity of the patients with preoperative Rankin scores of 0 or 1 was 1.3%. Transient morbidity was observed in 6 patients (7.7%) with the size of the aneurysm 19.8 mm on average. The natural history and surgical results in patients with UIAs are modified by several factors including aneurysm size and location, the patient's age and gender, the medical status and the patient's preoperative Rankin score. The present results indicated that these factors should be considered in deciding whether to treat UIAs, and that careful assessment of the surgical benefits might be essential

Double microcatheter technique for coiling intracranial aneurysms with unfavorable configurations

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WANG Shu-yuan

2013-03-01

Full Text Available Background Although stent-assisted technique has been widely used clinically, it is still hard to perform coiling treatment for complicated intracranial aneurysms, including relatively wide-necked tiny aneurysms and lobulated wide-necked aneurys ms with important branch vessels arising from the neck. This study aims to investigate the feasibility and clinical results of endovascular treatment for intracranial aneurysms with unfavorable configurations by using double microcatheter technique. Methods Thirty-three cases with complicated aneurysms were treated by using double microcatheter technique from April 2008 to November 2012. The locations of these aneurysms were anterior communicating artery (7 cases, posterior communicating artery (14 cases, ophthalmic artery (3 cases, anterior choroidal artery (3 cases, origin of posterior inferior cerebellar artery (3 cases, bifurcation of middle cerebral artery (2 cases and top of basilar artery (1 case. The mean neck- to-body (width ratio was 0.80 ± 0.21 (0.53-1.33. The mean body (width-to-dome (height ratio was 1.12 ± 0.37 (0.55-2.12. The mean dome (height-to-neck ratio was 1.26 ± 0.41 (0.65-2.96. The diameter of neck ≥4 mm was seen in 7 aneurysms, neck≥height in 9 and neck ≥width in 8. Besides, there were 9 very small aneurysms (the maximum diameter≤3 mm and 13 aneurysms with important branch vessels arising from the neck. All of these aneurysms were treated with coiling by using double microcatheter technique. Results All aneurysms were successfully embolized. Immediate postembolization angiography showed no residual contrast filling in 19 aneurysms, and residual filling in 14. There were some small loops protruding from the neck without influencing the blood flow in 12 cases. At discharge, according to modified Rankin Scale (mRS, 30 patients with 0-1 scores presented excellent clinical outcomes and 3 patients with 2 scores had cognitive dysfunction and moderate disability due to vasospasm

A case of acute ischemic colitis after endovascular abdominal aortic aneurysm repair

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Grigorios Voulalas

2016-01-01

Full Text Available Colonic ischemia is a recognized complication of either open or endovascular abdominal aortic aneurysm repair. The clinical difficulty in establishing the diagnosis, the severity of this complication and the patient's poor physiological status may lead to a fatal outcome. We presented a case of ischemic colitis in a patient with patent hypogastric arteries that occurred after an endovascular abdominal aortic aneurysm repair as well as a review of the available literature. The patient's preoperative, intraoperative and postoperative data were recorded. A thorough search through the Google data and Medline to review similar cases or any analyses that referred to ischemic colitis after endovascular abdominal aneurysm repair was conducted. A 76-year-old male was admitted to our department for an elective endovascular repair of an 8 cm in diameter abdominal aortic aneurysm. A Zenith bifurcation graft was implanted. The whole procedure was uneventful and the final angiogram showed an accurate deployment of the endograft without endoleaks and patency of both hypogastric arteries. During the 1st postoperative day, the patient developed symptoms of acute abdomen in combination with metabolic acidosis and oliguria. He underwent an exploratory laparotomy, which revealed necrosis of the sigmoid. A Hartmann's procedure was performed; the patient was transferred to the intensive care unit where he deceased after 24 h. Postoperative ischemic colitis has been described after open abdominal aneurysm repair. The description of this complication has been reported since the early phase of endovascular abdominal aneurysm repair development with a current incidence of 1.5%–3.0%. Possible mechanisms that may contribute to ischemic colitis in spite of the presence of patent hypogastric arteries include atheroembolization, shock, vasopressive drugs and inferior mesenteric artery occlusion.

Development of an artifact-free aneurysm clip

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Brack Alexander

2016-09-01

Full Text Available For the treatment of intracranial aneurysms with aneurysm clips, usually a follow-up inspection in MRI is required. To avoid any artifacts, which can make a proper diagnosis difficult, a new approach for the manufacturing of an aneurysm clip entirely made from fiber-reinforced plastics has been developed. In this paper the concept for the design of the clip, the development of a new manufacturing technology for the fiber-reinforced components as well as first results from the examination of the components in phantom MRI testing is shown.

Dosimetric study for the development of heterogeneous chest phantom for the purpose of patient-specific quality assurance

International Nuclear Information System (INIS)

Gurjar, Om Prakash; Mishra, Praveen Kumar; Mishra, Surendra Prasad; Singh, Navin; Bagdare, Priyusha

2015-01-01

To analyze the dose absorption patterns of 6 Megavoltage (MV) photon beam using computed tomography (CT) slices of thorax of patient, slab phantom, and slab-kailwood-slab phantom. Single beam of 6 MV with field size of 10 X 10 cm 2 was put on CT images of chest wall, slab phantom, and slab-kailwood-slab phantom perpendicular to the surface. Dose was calculated using anisotropic analytical algorithm. Densities of each medium were calculated by Hounsfield units measured from CT images of each medium. The depths of isodose curves of 100%, 95%, 90%, 85%, 80%, 70%, 60%, and 50% were measured in all the three mediums. The densities measured for chest wall, lung, Soft tissue behind lung, slab phantom, and slab-kailwood-slab phantom were 0.89, 0.301, 1.002, 0.998, and 0.379 g/cc, respectively. The isodose depth (100%, 95%, 90%, 85%, 80%, and 50%) for patient (1.5, 2.76, 3.97, 5.33, 7.01, and 20.01 cm), slab phantom (1.5, 2.74, 3.92, 5.06, 6.32, and 15.18 cm), and slab-kailwood-slab phantom (1.5, 2.65, 3.86, 4.98, 5.95, and 20 cm) is approximately same for 100%, 95%, 90%, and 85% isodose curves. The isodose depth pattern in the chest is equivalent to that in slab-kailwood-slab phantom. The radiation properties of the slab-kailwood-slab phantom are equivalent to that of chest wall, lung, and soft tissue in actual human. The chest phantom mimicking the actual thoracic region of human can be manufactured using polystyrene and the kailwood. (author)

Hybrid treatment of a true thyreocervical trunk aneurysm in a patient with Type B aortic dissection

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Nikolaos G Baikoussis

2016-01-01

Full Text Available We would like to describe a case with a complex aortic disease treated in hybrid fashion. We present an interesting case of a 65-year-old man with a medical history of hypertension, hyperlipidemia, and coronary artery disease percutaneously treated. An acute Type B aortic dissection occurred and treated with the implantation of a stent-graft which occluded the left subclavian artery due to its extension to the aortic arch. This event required a carotid-subclavian artery bypass due to ischemia of the left arm. An aneurysm in the innominate artery also detected, was treated with another stent-graft implantation 3 months later. At 5-year follow-up, an aneurysm of the thyreocervical trunk was found while the stent-graft of the aorta was well-tolerated without endoleak and the carotid-subclavian graft was patent. The aneurysm was asymptomatic but considering the risk of spontaneous rupture of an aneurysm of this size, elective surgery was indicated. Because the aneurysm was very close to the brachiocephalic bifurcation, open surgical repair would require a sternotomy. The right common carotid artery and right subclavian artery were exposed. The thyrocervical trunk, right internal mammary artery and right vertebral artery were occluded by ligations to isolate the aneurysm. An 8-mm Dacron graft was anastomosed end-to-end to the distal part of subclavian artery. We would like through this case, discuss the role of the hybrid cardiovascular surgery to minimize the postoperative complications in complex cardiovascular pathology. We also discuss the international bibliography about the thyreocervical trunk aneurysm and the treatment options.

Initial clinical experience with a sac-anchoring endoprosthesis for aortic aneurysm repair.

Science.gov (United States)

Donayre, Carlos E; Zarins, Christopher K; Krievins, Dainis K; Holden, Andrew; Hill, Andrew; Calderas, Carlos; Velez, Jaime; White, Rodney A

2011-03-01

All current aortic endografts depend on proximal and distal fixation to prevent migration. However, migration and rupture can occur, particularly in patients with aortic necks that are short or angulated, or both. We present our initial clinical experience with a new sac-anchoring endoprosthesis designed to anchor and seal the device within the aneurysm sac. The initial worldwide experience using a new endoprosthesis for the treatment of aortic aneurysms (Nellix Endovascular, Palo Alto, Calif) was reviewed. The endoprosthesis consists of dual balloon-expandable endoframes surrounded by polymer-filled endobags designed to obliterate the aneurysm sac and maintain endograft position. Clinical results and follow-up contrast computed tomography (CT) scans at 30 days and 6 and 12 months were reviewed. The endograft was successfully deployed in 21 patients with infrarenal aortic aneurysms measuring 5.7 ± 0.7 cm (range, 4.3-7.4 cm). Two patients with common iliac aneurysms were treated with sac-anchoring extenders that maintained patency of the internal iliac artery. Infusion of 71 ± 37 mL of polymer (range, 19-158 mL) into the aortic endobags resulted in complete aneurysm exclusion in all patients. Mean implant time was 76 ± 35 minutes, with 33 ± 17 minutes of fluoroscopy time and 180 ± 81 mL of contrast; estimated blood loss was 174 ± 116 mL. One patient died during the postoperative period (30-day mortality, 4.8%), and one died at 10 months from non-device-related causes. During a mean follow-up of 8.7 ± 3.1 months and a median of 6.3 months, there were no late aneurysm- or device-related adverse events and no secondary procedures. CT imaging studies at 6 months and 1 year revealed no increase in aneurysm size, no device migration, and no new endoleaks. One patient had a limited proximal type I endoleak at 30 days that resolved at 60 days and remained sealed. One patient has an ongoing distal type I endoleak near the iliac bifurcation, with no change in aneurysm

Intracranial Aneurysms of Neuro-Ophthalmologic Relevance.

Science.gov (United States)

Micieli, Jonathan A; Newman, Nancy J; Barrow, Daniel L; Biousse, Valérie

2017-12-01

Intracranial saccular aneurysms are acquired lesions that often present with neuro-ophthalmologic symptoms and signs. Recent advances in neurosurgical techniques, endovascular treatments, and neurocritical care have improved the optimal management of symptomatic unruptured aneurysms, but whether the chosen treatment has an impact on neuro-ophthalmologic outcomes remains debated. A review of the literature focused on neuro-ophthalmic manifestations and treatment of intracranial aneurysms with specific relevance to neuro-ophthalmologic outcomes was conducted using Ovid MEDLINE and EMBASE databases. Cavernous sinus aneurysms were not included in this review. Surgical clipping vs endovascular coiling for aneurysms causing third nerve palsies was compared in 13 retrospective studies representing 447 patients. Complete recovery was achieved in 78% of surgical patients compared with 44% of patients treated with endovascular coiling. However, the complication rate, hospital costs, and days spent in intensive care were reported as higher in surgically treated patients. Retrospective reviews of surgical clipping and endovascular coiling for all ocular motor nerve palsies (third, fourth, or sixth cranial nerves) revealed similar results of complete resolution in 76% and 49%, respectively. Improvement in visual deficits related to aneurysmal compression of the anterior visual pathways was also better among patients treated with clipping than with coiling. The time to treatment from onset of visual symptoms was a predictive factor of visual recovery in several studies. Few reports have specifically assessed the improvement of visual deficits after treatment with flow diverters. Decisions regarding the choice of therapy for intracranial aneurysms causing neuro-ophthalmologic signs ideally should be made at high-volume centers with access to both surgical and endovascular treatments. The status of the patient, location of the aneurysm, and experience of the treating physicians

Preliminary Study of Hemodynamic Distribution in Patient-Specific Stenotic Carotid Bifurcation by Image-Based Computational Fluid Dynamics

International Nuclear Information System (INIS)

Xue, Y.J.; Gao, P.Y.; Duan, Q.; Lin, Y.; Dai, C.B.

2008-01-01

Background: Regions prone to atherosclerosis, such as bends and bifurcations, tend to exhibit a certain degree of non-planarity or curvature, and these geometric features are known to strongly influence local flow patterns. Recently, computational fluid dynamics (CFD) has been used as a means of enhancing understanding of the mechanisms involved in atherosclerotic plaque formation and development. Purpose: To analyze flow patterns and hemodynamic distribution in stenotic carotid bifurcation in vivo by combining CFD with magnetic resonance angiography (MRA). Material and Methods: Twenty-one patients with carotid atherosclerosis proved by digital subtraction angiography (DSA) and/or Doppler ultrasound underwent contrast-enhanced MR angiography of the carotid bifurcation by a 3.0T MR scanner. Hemodynamic variables and flow patterns of the carotid bifurcation were calculated and visualized by combining vascular imaging postprocessing with CFD. Results: In mild stenotic cases, there was much more streamlined flow in the bulbs, with reduced or disappeared areas of weakly turbulent flow. Also, the corresponding areas of low wall shear stress (WSS) were reduced or even disappeared. As the extent of stenosis increased, stronger blood jets formed at the portion of narrowing, and more prominent eddy flows and slow back flows were noted in the lee of the stenosis. Regions of elevated WSS were predicted at the portion of stenosis and in the path of the downstream jet. Areas of low WSS were predicted on the leeward side of the stenosis, corresponding with the location of slowly turbulent flows. Conclusion: CFD combined with MRA can simulate flow patterns and calculate hemodynamic variables in stenotic carotid bifurcations as well as normal ones. It provides a new method to investigate the relationship of vascular geometry and flow condition with atherosclerotic pathological changes

Sex-related differences in patients treated surgically for aneurysmal subarachnoid hemorrhage

International Nuclear Information System (INIS)

Horiuchi, Tetsuyoshi; Tanaka, Yuichiro; Hongo, Kazuhiro

2006-01-01

Sex-related differences were examined in the clinical course of patients treated surgically for aneurysmal subarachnoid hemorrhage. Retrospective analyses were carried out to evaluate sex-related differences in aneurysm location, aneurysm size, preoperative neurological condition, preoperative computed tomography findings, and outcome among 2577 patients who underwent surgical repair of ruptured aneurysms. The internal carotid artery was most frequently affected in women and the anterior cerebral artery in men. Intracerebral or intraventricular hematoma was more common in men than in women. Some differences may be related to the location of the aneurysm. Sex-related differences were prominent in the 5th decade of life. These findings might be related to the menopause. Sex hormones may be involved in aneurysm formation. (author)

A 4D Digital Phantom for Patient-Specific Simulation of Brain CT Perfusion Protocols

NARCIS (Netherlands)

Boom, R. van den; Manniesing, R.; Oei, M.T.H.; Woude, W.J. van der; Smit, E.J.; Laue, H.O.A.; Ginneken, B. van; Prokop, M.

2014-01-01

Purpose Optimizing CT brain perfusion protocols is a challenge because of the complex interaction between image acquisition, calculation of perfusion data and patient hemodynamics. Several digital phantoms have been developed to avoid unnecessary patient exposure or suboptimum choice of parameters.

Risk of rupture of unruptured cerebral aneurysms in elderly patients

Science.gov (United States)

Date, Isao; Tokunaga, Koji; Tominari, Shinjiro; Nozaki, Kazuhiko; Shiokawa, Yoshiaki; Houkin, Kiyohiro; Murayama, Yuichi; Ishibashi, Toshihiro; Takao, Hiroyuki; Kimura, Toshikazu; Nakayama, Takeo; Morita, Akio

2015-01-01

Objectives: The aim of this study was to identify risk factors for rupture of unruptured cerebral aneurysms (UCAs) in elderly Japanese patients aged 70 years or older. Methods: The participants included all patients 70 years of age or older in 3 prospective studies in Japan (the Unruptured Cerebral Aneurysm Study of Japan [UCAS Japan], UCAS II, and the prospective study at the Jikei University School of Medicine). A total of 1,896 patients aged 70 years or older with 2,227 UCAs were investigated. The median and mean follow-up periods were 990 and 802.7 days, respectively. Results: The mean aneurysm size was 6.2 ± 3.9 mm. Sixty-eight patients (3.6%) experienced subarachnoid hemorrhage during the follow-up period. Multivariable analysis per patient revealed that in patients aged 80 years or older (hazard ratio [HR], 2.02; 95% confidence interval [CI], 1.16–3.49, p = 0.012), aneurysms 7 mm or larger (HR, 3.08; 95% CI, 1.35–7.03, p = 0.007 for 7–9 mm; HR, 7.82; 95% CI, 3.60–16.98, p < 0.001 for 10–24 mm; and HR, 43.31; 95% CI, 12.55–149.42, p < 0.001 for ≥25 mm) and internal carotid–posterior communicating artery aneurysms (HR, 2.45; 95% CI, 1.23–4.88, p = 0.011) were independent predictors for UCA rupture in elderly patients. Conclusions: In our pooled analysis of prospective cohorts in Japan, patient age and aneurysm size and location were significant risk factors for UCA rupture in elderly patients. PMID:26511450

Assessment of long-term effects of aneurysms trapping and extracranial-intracranial bypass surgery in patients with complex cerebral aneurysms

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MAO Zhi-qi

2012-02-01

Full Text Available Objective To study the long-term effects of extracranial-intracranial (EC-IC bypass and aneurysms trapping in patients with complex cerebral aneurysms. Methods Seventeen patients with complex aneurysms, who underwent EC-IC bypass and aneurysms trapping from 2008 to 2009, were followed up. Clinical records were reviewed, modified Rankin Scale (mRS was recorded at admission, discharging, and follow-up point, and activities of daily living (ADL scale (Barthel Index at admission and follow-up point. Results Seventeen patients (11 males and 6 females were followed up. At admission mRS scores were 1.06 ± 0.87, Barthel index 91.10 ± 10.30. Superficial temporal artery-middle cerebral artery (STA-MCA was performed in 8 cases, extracarotid artery-great saphenous vein-middle cerebral artery (ECA-GSV-MCA in 5 cases, extracarotid artery-radial artery-middle cerebral artery (ECA-RA-MCA in 3 cases, occipital artery-posterior inferior cerebellar artery (OA-PICA in 1 case. Patients were followed up for 19-39 months (mean 28.67 months. At follow-up point, 2 patients (11.76% died, operation-related mortality was 5.88% (1/17, operation-related morbidity 5.88% (1/17, mRS scores 1.07 ± 1.16, Barthel index 96.40 ± 10.30. Conclusion Patients with complex aneurysms who were impossible to be treated with surgical clipping or endovascular intervention could be cured with extracranial-intracranial bypass and aneurysms trapping, and good follow-up results were acquired.

Development of a voxel phantom specific for simulation of eye brachytherapy

International Nuclear Information System (INIS)

Santos, Marcilio S.; Lima, Fernando R.A.

2013-01-01

The ophthalmic brachytherapy involves inserting a plate with seeds of radioactive material in the patient's eye for the treatment of tumors. The radiation dose to be taken by the patient is prescribed by physicians and time of application of the material is calculated from calibration curves supplied by the manufacturers of the plates. To estimate the dose absorbed by the patient, in a series of diagnostic tests, it is necessary to perform simulations using a computational model of exposure. These models are composed primarily by a anthropomorphic phantom, and a Monte Carlo code. The coupling of a phantom voxel whole body to a Monte Carlo code is a complex process because the computer model simulations with exposure takes time, knowledge of the code used and various adjustments to be implemented. The problem is aggravated even more complex when you want to radiate one region of the body. In this work we developed a phantom, specifically the region containing the eyeball, from MASH (Male Adult voxel). This model was coupled to the Monte Carlo code EGSnrc (Electron Gamma Shower) together with an algorithm simulator source of I-125 , considering only its effect of higher energy range

Aneurysm pulsatility after endovascular exclusion: an experimental study using human aortic aneurysms

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Hussein Amin Orra

2008-01-01

Full Text Available OBJECTIVE: To measure the pulsatility of human aneurysms before and after complete exclusion with an endograft. METHOD: Five aortic aneurysms obtained during necropsy were submitted to pulsatile perfusion before and after implantation of a bifurcated endograft. The specimens were contained in a closed chamber filled with saline solution. A vertical tube attached to the chamber was used to measure volume dislocation in each systole. Mural thrombus was kept intact, and the space around the device was filled with human blood. After each experiment, the aneurysm was opened to check for the correct positioning and attachment of the device. RESULTS: The level of the saline column oscillated during pulsation in each case, with respective amplitudes of 17, 16, 13, 7, and 25 cm before the endograft insertion. After the insertion, the amplitudes dropped to 13, 12, 9, 3.5, and 23 cm, respectively. The differences were not significant. During the post-experimental examination, all devices were found to be in position and well attached to the neck and iliacs. No endoleak was detected during perfusion or by visual inspection. CONCLUSION: Pulsation of an endograft is transmitted to the aneurysm wall even in the absence of endoleak, and should not be interpreted as procedural failure.

Enterprise Deployment Through PulseRider To Treat Anterior Communicating Artery Aneurysm Recurrence.

Science.gov (United States)

Valente, Iacopo; Limbucci, Nicola; Nappini, Sergio; Rosi, Andrea; Laiso, Antonio; Mangiafico, Salvatore

2018-02-01

PulseRider (Pulsar Vascular, Los Gatos, California, USA) is a new endovascular device designed to treat wide-neck bifurcation intracranial aneurysms. Deployment of a stent through a PulseRider to treat an aneurysm's recurrence has never been described before. We report the case of a 55-year-old man who underwent coiling of an 8-mm anterior communicating artery aneurysm with assistance of a PulseRider neck reconstruction device. The 6-month digital subtraction angiography control showed aneurysm recurrence, so we deployed an Enterprise 2 closed-cell stent (Codman, Miami Lakes, Florida, USA) in the A1-A2 segment passing across the previously implanted PulseRider. Enterprise correctly expanded and allowed for adequate coiling of the aneurysm. An Enterprise stent can be safely opened through a PulseRider in order to treat aneurysm recurrence. Copyright © 2017 Elsevier Inc. All rights reserved.

Thoracoabdominal aortic aneurysm repair in patients with marfan syndrome.

Science.gov (United States)

Mommertz, G; Sigala, F; Langer, S; Koeppel, T A; Mess, W H; Schurink, G W H; Jacobs, M J

2008-02-01

We assessed the surgical outcome of descending thoracic aortic aneurysm repair (DTAA) and thoracoabdominal aortic aneurym (TAAA) repair in patients with Marfan syndrome. During a six year period, 206 patients underwent DTAA and TAAA repair. In 22 patients, Marfan syndrome was confirmed. The median age was 40 years with a range between 18 and 57 years. The extend of the aneurysms included 6 DTAA (1 with total arch, 2 with distal hemi-arch), 11 type II TAAA (2 with total arch, 3 with distal hemi-arch), 4 type III and one type IV TAAA. All patients suffered from previous type A (n=6) or type B (n=16) aortic dissection and 15 already underwent aortic procedures like Bentall (n=7) and ascending aortic replacement (n=8). All patients were operated on according to the standard protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials. In patients undergoing simultaneous arch replacement (via left thoracotomy), transcranial Doppler and EEG assessed cerebral physiology during antegrade brain perfusion. In four patients circulatory arrest under moderate hypothermia was required. In-hospital mortality did not occur. Major postoperative complications like paraplegia, renal failure, stroke and myocardial infarction were not encountered. Mean pre-operative creatinine level was 125mmol/L, which peaked to a mean maximal level of 130 and returned to 92mmol/L at discharge. Median intubation time was 1.5 days (range 0.33-30 days). Other complications included bleeding requiring surgical intervention (n=1), arrhythmia (n=2), pneumonia (n=2) and respiratory distress syndrome (n=1). At a median follow-up of 38 months all patients were alive. Using CT surveillance, new or false aneurysms were not detected, except in one patient who developed a visceral patch aneurysm six years after open type II repair. Surgical repair of descending and thoracoabdominal aortic aneurysms provides excellent short- and mid-term results in

Real-time surgery simulation of intracranial aneurysm clipping with patient-specific geometries and haptic feedback

Science.gov (United States)

Fenz, Wolfgang; Dirnberger, Johannes

2015-03-01

Providing suitable training for aspiring neurosurgeons is becoming more and more problematic. The increasing popularity of the endovascular treatment of intracranial aneurysms leads to a lack of simple surgical situations for clipping operations, leaving mainly the complex cases, which present even experienced surgeons with a challenge. To alleviate this situation, we have developed a training simulator with haptic interaction allowing trainees to practice virtual clipping surgeries on real patient-specific vessel geometries. By using specialized finite element (FEM) algorithms (fast finite element method, matrix condensation) combined with GPU acceleration, we can achieve the necessary frame rate for smooth real-time interaction with the detailed models needed for a realistic simulation of the vessel wall deformation caused by the clamping with surgical clips. Vessel wall geometries for typical training scenarios were obtained from 3D-reconstructed medical image data, while for the instruments (clipping forceps, various types of clips, suction tubes) we use models provided by manufacturer Aesculap AG. Collisions between vessel and instruments have to be continuously detected and transformed into corresponding boundary conditions and feedback forces, calculated using a contact plane method. After a training, the achieved result can be assessed based on various criteria, including a simulation of the residual blood flow into the aneurysm. Rigid models of the surgical access and surrounding brain tissue, plus coupling a real forceps to the haptic input device further increase the realism of the simulation.

A nursing case history: the patient with mycotic aneurysm secondary to endocarditis.

Science.gov (United States)

Leith, B; Furimsky, I

1995-03-01

Due to the advent of antibiotics, mycotic aneurysms, also known as infective aneurysms, now represent only 2.5-5% of all aneurysms. The existing research on this topic is old and scarce. It is highly probably that a neuroscience nurse will care for this type of patient at some point during his/her career. The patient with a mycotic aneurysm is usually critically ill. A 46% mortality has been noted and is related to the multiple problems of these types of patients. Currently, if and when to surgically intervene is controversial. The case of "Mr. C.", a patient at the Montreal Neurological Hospital who developed a mycotic aneurysm secondary to subacute bacterial endocarditis, will be presented. His course in hospital, the medical management and treatment as well as the nursing care and educational needs will be described.

DOMINANCE OF CORONARY ARTERY DISEASE AMONG PATIENTS WITH ANEURYSM OF ABDOMINAL AORTA

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Maja Zdravkovic

2007-12-01

Full Text Available Persons with aneurysm of the abdominal aorta have high prevalence of risk factors of cardiovascular disease. It cannot be stated with certainty whether these persons die in a large number due to the existence of risk factors or the genesis and complications of aneurysm itself. In patients with aneurysm of the abdominal aorta, there is a high correlation with the coronary artery disease; therefore, the aim of the study was to prove whether or not this is the case. The patients in preparation for the resection of the abdominal aorta aneurysm at the Institute of Cardiovascular Disease underwent the examination. The study included 377 examinees, of whom 341 males and 36 females, aged 45 to 83 years, during the three-year interval (from 2004 to 2006. The aim of the study was to determine the dominance of the coronary artery disease among the patients with aneurysm of the abdominal aorta. In the process of analyzing the data obtained from patients and medical evidence, it was found out that a large number of the abdominal aortic aneurysm patients were at the same time the coronary artery disease patients (55,2%; Hi=15,04; p80 kg was larger, as well as the percentage of patients with hypertension (89% and increased levels of cholesterol and triglycerides (67%. There was a great number of those with the inherited factor (40%. It has been proven that the risk factors for the development of coronary artery disease are in direct association with the risk factors for the abdominal aortic aneurysm. Also, there is a great predominance of the coronary artery disease among the patients with aneurysm of the abdominal aorta. The coronary artery disease is one of the main risk factors. If we managed to prevent the appearance of this disease or achieve the timely diagnosing of it and eventual curing, we would be able to decrease the development of the abdominal aortic aneurysm well as the consequences and further complications.

Determination of wall tension in cerebral artery aneurysms by numerical simulation

DEFF Research Database (Denmark)

Isaksen, J.G.; Bazilevs, Y.; Kvamsdal, T.

2008-01-01

a computational model for simulation of fluid-structure interaction in cerebral aneurysms based on patient specific lesion geometry, with special emphasis on wall tension. METHODS: An advanced isogeometric fluid-structure analysis model incorporating flexible aneurysm wall based on patient specific computed...

The safety of vasopressor-induced hypertension in subarachnoid hemorrhage patients with coexisting unruptured, unprotected intracranial aneurysms.

Science.gov (United States)

Reynolds, Matthew R; Buckley, Robert T; Indrakanti, Santoshi S; Turkmani, Ali H; Oh, Gerald; Crobeddu, Emanuela; Fargen, Kyle M; El Ahmadieh, Tarek Y; Naidech, Andrew M; Amin-Hanjani, Sepideh; Lanzino, Giuseppe; Hoh, Brian L; Bendok, Bernard R; Zipfel, Gregory J

2015-10-01

Vasopressor-induced hypertension (VIH) is an established treatment for patients with aneurysmal subarachnoid hemorrhage (SAH) who develop vasospasm and delayed cerebral ischemia (DCI). However, the safety of VIH in patients with coincident, unruptured, unprotected intracranial aneurysms is uncertain. This retrospective multiinstitutional study identified 1) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who required VIH therapy (VIH group), and 2) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who did not require VIH therapy (non-VIH group). All patients had previously undergone surgical or endovascular treatment for the presumed ruptured aneurysm. Comparisons between the VIH and non-VIH patients were made in terms of the patient characteristics, clinical and radiographic severity of SAH, total number of aneurysms, number of ruptured/unruptured aneurysms, aneurysm location/size, number of unruptured and unprotected aneurysms during VIH, severity of vasospasm, degree of hypervolemia, and degree and duration of VIH therapy. For the VIH group (n = 176), 484 aneurysms were diagnosed, 231 aneurysms were treated, and 253 unruptured aneurysms were left unprotected during 1293 total days of VIH therapy (5.12 total years of VIH therapy for unruptured, unprotected aneurysms). For the non-VIH group (n = 73), 207 aneurysms were diagnosed, 93 aneurysms were treated, and 114 unruptured aneurysms were left unprotected. For the VIH and non-VIH groups, the mean sizes of the ruptured (7.2 ± 0.3 vs 7.8 ± 0.6 mm, respectively; p = 0.27) and unruptured (3.4 ± 0.2 vs 3.2 ± 0.2 mm, respectively; p = 0.40) aneurysms did not differ. The authors observed 1 new SAH from a previously unruptured, unprotected aneurysm in each group (1 of 176 vs 1 of 73 patients; p = 0.50). Baseline patient characteristics and comorbidities were similar between groups. While the degree of hypervolemia was similar between the VIH and non-VIH patients

Hemodynamic vascular biomarkers for initiation of paraclinoid internal carotid artery aneurysms using patient-specific computational fluid dynamic simulation based on magnetic resonance imaging.

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Watanabe, Tomoya; Isoda, Haruo; Takehara, Yasuo; Terada, Masaki; Naito, Takehiro; Kosugi, Takafumi; Onishi, Yuki; Tanoi, Chiharu; Izumi, Takashi

2018-05-01

We performed computational fluid dynamics (CFD) for patients with and without paraclinoid internal carotid artery (ICA) aneurysms to evaluate the distribution of vascular biomarkers at the aneurysm initiation sites of the paraclinoid ICA. This study included 35 patients who were followed up for aneurysms using 3D time of flight (TOF) magnetic resonance angiography (MRA) and 3D cine phase-contrast MR imaging. Fifteen affected ICAs were included in group A with the 15 unaffected contralateral ICAs in group B. Thirty-three out of 40 paraclinoid ICAs free of aneurysms and arteriosclerotic lesions were included in group C. We deleted the aneurysms in group A based on the 3D TOF MRA dataset. We performed CFD based on MR data set and obtained wall shear stress (WSS), its derivatives, and streamlines. We qualitatively evaluated their distributions at and near the intracranial aneurysm initiation site among three groups. We also calculated and compared the normalized highest (nh-) WSS and nh-spatial WSS gradient (SWSSG) around the paraclinoid ICA among three groups. High WSS and SWSSG distribution were observed at and near the aneurysm initiation site in group A. High WSS and SWSSG were also observed at similar locations in group B and group C. However, nh-WSS and nh-SWSSG were significantly higher in group A than in group C, and nh-SWSSG was significantly higher in group A than in group B. Our findings indicated that nh-WSS and nh-SWSSG were good biomarkers for aneurysm initiation in the paraclinoid ICA.

Aneurysm and dissection in a patient with syphilitic aortitis

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Fernando Pivatto Júnior

2017-05-01

Full Text Available In the antibiotic era, aortic aneurysm is a rare complication of syphilis, what makes the diagnostic assumption even more difficult. Nonetheless, this condition should be suspected in patients with aortic aneurysm. Reports of aortic dissection complicating syphilitic aortitis have been distinctly rare in the literature, and their cause-effect relationship has not been definitely established. In this case report, we present a 62-year-old woman with aortic aneurysm and dissection associated with an unexpected diagnosis of syphilitic aortitis.

Evaluation of the levels of metalloproteinsase-2 in patients with abdominal aneurysm and abdominal hernias.

Science.gov (United States)

Antoszewska, Magdalena

2013-05-01

Abdominal aortic aneurysms and abdominal hernias become an important health problems of our times. Abdominal aortic aneurysm and its rupture is one of the most dangerous fact in vascular surgery. There are some theories pointing to a multifactoral genesis of these kinds of diseases, all of them assume the attenuation of abdominal fascia and abdominal aortic wall. The density and continuity of these structures depend on collagen and elastic fibers structure. Reducing the strength of the fibers may be due to changes in the extracellular matrix (ECM) by the proteolytic enzymes-matrix metalloproteinases (MMPs) that degrade extracellular matrix proteins. These enzymes play an important role in the development of many disease: malignant tumors (colon, breast, lung, pancreas), cardiovascular disease (myocardial infarction, ischemia-reperfusion injury), connective tissue diseases (Ehler-Danlos Syndrome, Marfan's Syndrome), complications of diabetes (retinopathy, nephropathy). One of the most important is matrix metalloproteinase-2 (MMP-2). The aim of the study was an estimation of the MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia, and in patients with only abdominal aortic aneurysm. The study involved 88 patients aged 42 to 89 years, including 75 men and 13 women. Patients were divided into two groups: patients with abdominal aortic aneurysm and primary abdominal hernia (45 persons, representing 51.1% of all group) and patients with only abdominal aortic aneurysm (43 persons, representing 48,9% of all group). It was a statistically significant increase in MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia compared to patients with only abdominal aortic aneurysm. It was a statistically significant increase in the prevalence of POCHP in patients with only abdominal aortic aneurysm compared to patients with abdominal aortic aneurysm and primary abdominal hernia. Statistically significant

Aneurysmal bone cyst primary - about eight pediatric cases ...

African Journals Online (AJOL)

The aneurysmal bone cyst is a pseudotumoral lesion that can take several aspects. ... specific forms and atypical aneurysmal bone cyst which often pose a diagnostic challenge requiring radiological ... All patients had standard radiographs.

Endovascular repair as a sole treatment in multiple aneurysms in patient with SLE

International Nuclear Information System (INIS)

Dineva, S.; Al-Amin, M.; Demetriou, S.; Tsetis, D.

2013-01-01

Full text: Introduction: Most aneurysms are local manifestations of systemic disease. For patients over 65 years the incidence of aneurysm of the abdominal aorta (AAA) is approximately 5-6% in men and 1-2 % for women. The presence of both the AAA and aneurysms in other location is even rarer, and this percentage is likely increase further in patients with systemic lupus erythematosus (SLE). What you will learn: We present a rare clinical case of endovascular treatment of multifocal aneurysm including post catheterization pseudoaneurysm. The patient is a 73 years old woman with a history of SLE and age-related comorbidity. Originally an endovascular treatment of aneurysms of the abdominal aorta and right common iliac artery was used. Two years later a successfully endovascular treatment of aneurysm of the right renal artery was conducted, which however is complicated by the formation of a pseudoaneurysm in access through the left femoral artery. The late one is again treated endovascular by placement of a covered stent after failure of percutaneous injection of 1000 UI thrombin. Discussion: Adult patients with a long history of SLE are unsuitable candidates for surgical treatment of aneurysmal disease, especially in its multifocal form. In our case we have taken multistep successful endovascular procedures, including technically hard placing of the stent at the site of the right renal aneurysms, and post catheterization pseudoaneurysm. Conclusion: Multifocal aneurysmal vascular changes due to macroangiopathia in SLE can be treated alone by endovascular means in multi-stages procedures

Tube Stent-Grafts for Infrarenal Aortic Aneurysm: A Matched-Paired Analysis Based on EUROSTAR Data

International Nuclear Information System (INIS)

Ruppert, Volker; Leurs, Lina J.; Hobo, Roel; Buth, Jacob; Rieger, Johannes; Umscheid, Thomas

2007-01-01

Objective. Tube stent-grafts for treatment of infrarenal aortic aneurysms (AAAs) are a nearly forgotten concept. For focal aortic pathologies tube stent-grafts may be a treatment option. We have performed a retrospective matched-paired analysis of the EUROSTAR registry regarding the outcome of tube vs. bifurcated stent-grafts for AAA. Tapered aortomonoiliac stent-grafts were not the objective of this study. Materials and methods. From July 1997 to June 2006, 7581 patients who underwent an endovascular AAA repair were entered in the EUROSTAR registry by 164 centers. One hundred fifty-three patients were treated with tube stent-grafts. For each of these 153 patients we selected one patient from a bifurcated stent-graft group (BGG-original, 7428 patients) matched according to gender, ASA, age, AAA diameter, and type of anesthesia. Differences in preoperative details between the two study groups were analyzed using chi-square test for discrete variables and Wilcoxon rank-sum test for continuous variables. Multivariate logistic regression analysis was performed on early complications. Midterm outcomes (>30 days) were analyzed by Kaplan-Meier and multivariate Cox proportional hazard model. Results. The duration of the procedure was shorter in the tube stent-graft group (TGG; 102.3 ± 52.2) than in BGG (128.3 ± 55.0; p 0.0002). Type II endoleak was less frequent in TGG (4.0%; mean follow-up, 23.12 ± 23.9 months) than in BGG (14.3%; mean follow-up, 20.77 ± 20.0 months; p = 0.0394). Type I endoleaks and migration were distributed equally, without significant differences between the groups. Combined 30-day and late mortality was higher for TGG (p = 0.0346) and was obviously not aneurysm related. Conclusions. We conclude that after selection of patients, tube stent-grafts for infrarenal aortic repair can be performed with great safety regarding endoleaks and migration. The combined higher 30-day mortality and non-aneurysm-related mortality during follow-up were mainly

The risk of intravenous thrombolysis-induced intracranial hemorrhage in Taiwanese patients with unruptured intracranial aneurysm.

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Wei Ting Chiu

Full Text Available The presence of an intracranial aneurysm is contraindicated to recombinant tissue plasminogen activator (r-tPA treatment for acute ischemic stroke. However, it is difficult to exclude asymptomatic intracranial aneurysms by using conventional, noncontrast head computed tomography (CT, which is the only neuroimaging suggested before r-tPA. Recent case reports and series have shown that administering r-tPA to patients with a pre-existing aneurysm does not increase the bleeding risk. However, Asians are known to have a relatively higher bleeding risk, and little evidence is available regarding the risk of using r-tPA on Asian patients with intracranial aneurysms.Medical records from the Shuang Ho hospital stroke registration between July 2010 and December 2014 were retrospectively reviewed, and 144 patients received r-tPA. Unruptured intracranial aneurysms were detected using CT, or magnetic resonance or conventional angiography after r-tPA. The primary and secondary outcomes were the difference in overall intracranial hemorrhage (ICH and symptomatic ICH after r-tPA. The differences were analyzed using Fisher's exact or Mann-Whitney U tests, and p < 0.05 was defined as the statistical significance.A total of 144 patients were reviewed, and incidental unruptured intracranial aneurysms were found in 11 of them (7.6%. No significant difference was observed in baseline demographic data between the aneurysm and nonaneurysm groups. Among patients with an unruptured aneurysm, two had giant aneurysms (7.7 and 7.4 mm, respectively. The bleeding risk was not significant different between aneurysm group (2 out of 11, 18% with nonaneurysm group (7 out of 133, 5.3% (p = 0.14. None of the patients with an unruptured aneurysm had symptomatic ICH, whereas one patient without an aneurysm exhibited symptomatic ICH.The presence of an unruptured intracranial aneurysm did not significantly increase the risk of overall and symptomatic ICH in Taiwanese patients after they

Advances in open microsurgery for cerebral aneurysms.

Science.gov (United States)

Davies, Jason M; Lawton, Michael T

2014-02-01

Endovascular techniques introduced strong extrinsic forces that provoked reactive changes in aneurysm surgery. Microsurgery has become less invasive, more appealing to patients, lower risk, and efficacious for complex aneurysms, particularly those unfavorable for or failing endovascular therapy. To review specific advances in open microsurgery for aneurysms. A university-based, single-surgeon practice was examined for the use of minimally invasive craniotomies, surgical management of recurrence after coiling, the use of intracranial-intracranial bypass techniques, and cerebrovascular volume-outcome relationships. The mini-pterional, lateral supraorbital, and orbital-pterional craniotomies are minimally invasive alternatives to standard craniotomies. Mini-pterional and lateral supraorbital craniotomies were used in one-fourth of unruptured patients, increasing from 22% to 28%, whereas 15% of patients underwent orbital-pterional craniotomies and trended upward from 11% to 20%. Seventy-four patients were treated for coil recurrences (2.3% of all aneurysms) with direct clip occlusion (77%), clip occlusion after coil extraction (7%), or parent artery occlusion with bypass (16%). Intracranial-intracranial bypass (in situ bypass, reimplantation, reanastomosis, and intracranial grafts) transformed the management of giant aneurysms and made the surgical treatment of posterior inferior cerebellar artery aneurysms competitive with endovascular therapy. Centralization maximized the volume-outcome relationships observed with clipping. Aneurysm microsurgery has embraced minimalism, tailoring the exposure to the patient's anatomy with the smallest possible craniotomy that provides adequate exposure. The development of intracranial-intracranial bypasses is an important advancement that makes microsurgery a competitive option for complex and recurrent aneurysms. Trends toward centralizing aneurysm surgery in tertiary centers optimize results achievable with open microsurgery.

Digital subtraction CT angiography for the detection of posterior inferior cerebellar artery aneurysms: comparison with digital subtraction angiography

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Chen, Guo Zhong; Luo, Song; Zhou, Chang Sheng; Zhang, Long Jiang; Lu, Guang Ming [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China)

2017-09-15

To evaluate the diagnostic accuracy of digital subtraction CT angiography (DS-CTA) in detecting posterior inferior cerebellar artery (PICA) aneurysms with digital subtraction angiography (DSA) as reference standard. A total of 115 patients, including 56 patients diagnosed with PICA aneurysms by CTA or DSA and 59 non-PICA-aneurysm patients were included in this retrospective study. All patients underwent DS-CTA and DSA. The site of PICA aneurysms and the pattern of haemorrhage were analysed. Sensitivity and specificity of DS-CTA without and with combining haemorrhage pattern in diagnosing PICA aneurysms were evaluated on a per patient and per aneurysm basis with DSA. Of 115 patients, 56 patients (48.7%) had 61 PICA aneurysms (size range, 1.1-13.5 mm; mean size, 4.9 ± 2.8 mm) on DSA. The sensitivity and specificity in depicting PICA aneurysms were 89.3% and 96.6% on a per patient basis and 90.2% and 93.4% on a per aneurysm basis, while the corresponding values were 94.6% and 96.6% on a per patient basis and 95.1% and 93.4% on a per aneurysm basis when combining with haemorrhage site. DS-CTA has a high sensitivity and specificity in detecting PICA aneurysms compared with DSA. It may be helpful for clinical diagnosis of PICA aneurysms to combine with haemorrhage sites. (orig.)

Local Delivery Is Critical for Monocyte Chemotactic Protein-1 Mediated Site-Specific Murine Aneurysm Healing.

Science.gov (United States)

Hourani, Siham; Motwani, Kartik; Wajima, Daisuke; Fazal, Hanain; Jones, Chad H; Doré, Sylvain; Hosaka, Koji; Hoh, Brian L

2018-01-01

Local delivery of monocyte chemotactic protein-1 (MCP-1/CCL2) via our drug-eluting coil has been shown to promote intrasaccular aneurysm healing via an inflammatory pathway. In this study, we validate the importance of local MCP-1 in murine aneurysm healing. Whether systemic, rather than local, delivery of MCP-1 can direct site-specific aneurysm healing has significant translational implications. If systemic MCP-1 is effective, then MCP-1 could be administered as a pill rather than by endovascular procedure. Furthermore, we confirm that MCP-1 is the primary effector in our MCP-1 eluting coil-mediated murine aneurysm healing model. We compare aneurysm healing with repeated intraperitoneal MCP-1 versus vehicle injection, in animals with control poly(lactic-co-glycolic) acid (PLGA)-coated coils. We demonstrate elimination of the MCP-1-associated tissue-healing response by knockout of MCP-1 or CCR2 (MCP-1 receptor) and by selectively inhibiting MCP-1 or CCR2. Using immunofluorescent probing, we explore the cell populations found in healed aneurysm tissue following each intervention. Systemically administered MCP-1 with PLGA coil control does not produce comparable aneurysm healing, as seen with MCP-1 eluting coils. MCP-1-directed aneurysm healing is eliminated by selective inhibition of MCP-1 or CCR2 and in MCP-1-deficient or CCR2-deficient mice. No difference was detected in M2 macrophage and myofibroblast/smooth muscle cell staining with systemic MCP-1 versus vehicle in aneurysm wall, but a significant increase in these cell types was observed with MCP-1 eluting coil implant and attenuated by MCP-1/CCR2 blockade or deficiency. We show that systemic MCP-1 concurrent with PLGA-coated platinum coil implant is not sufficient to produce site-specific aneurysm healing. MCP-1 is a critical, not merely complementary, actor in the aneurysm healing pathway.

Endovascular Embolization of Intracranial Infectious Aneurysms in Patients Undergoing Open Heart Surgery Using n-Butyl Cyanoacrylate.

Science.gov (United States)

Cheng-Ching, Esteban; John, Seby; Bain, Mark; Toth, Gabor; Masaryk, Thomas; Hui, Ferdinand; Hussain, Muhammad Shazam

2017-03-01

Mycotic aneurysms are a serious complication of infective endocarditis with increased risk of intracranial hemorrhage. Patients undergoing open heart surgery for valve repair or replacement are exposed to anticoagulants, increasing the risk of aneurysm bleeding. These patients may require endovascular or surgical aneurysm treatment prior to heart surgery, but data on this approach are scarce. Retrospective review of consecutive patients with infectious endocarditis and mycotic aneurysms treated endovascularly with Trufill n-butyl cyanoacrylate (n-BCA) at the Cleveland Clinic between January 2013 and December 2015. Nine patients underwent endovascular treatment of mycotic aneurysms with n-BCA (mean age of 39 years). On imaging, 4 patients had intracerebral hemorrhage, 2 had multiple embolic infarcts, and the rest had no imaging findings. Twelve mycotic aneurysms were detected (3 patients with 2 aneurysms). Seven aneurysms were in the M4 middle cerebral artery segment, 4 in the posterior cerebral artery distribution, and 1 in the callosomarginal branch. n-BCA was diluted in ethiodized oil (1:1 to 1:2). Embolization was achieved in a single rapid injection with immediate microcatheter removal. Complete aneurysm exclusion was achieved in all cases without complications. All patients underwent open heart surgery and endovascular embolization within a short interval, 2 with both procedures on the same day. There were no new hemorrhages after aneurysm embolization. Endovascular embolization of infectious intracranial aneurysms with liquid embolics can be performed successfully in critically ill patients requiring immediate open heart surgery and anticoagulation. Early embolization prior to and within a short interval from open heart surgery is feasible.

Endovascular Repair of Abdominal Aortic Aneurysms in the Presence of a Transplanted Kidney

International Nuclear Information System (INIS)

Silverberg, Daniel; Yalon, Tal; Halak, Moshe

2015-01-01

PurposeTo present our experience performing endovascular repair of abdominal aortic aneurysms in kidney transplanted patients.MethodsA retrospective review of all patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA) performed at our institution from 2007 to 2014. We identified all patients who had previously undergone a kidney transplant. Data collected included: comorbidities, preoperative imaging modalities, indication for surgery, stent graft configurations, pre- and postoperative renal function, perioperative complications, and survival rates.ResultsA total of 267 EVARs were performed. Six (2 %) had a transplanted kidney. Mean age was 74 (range, 64–82) years; five were males. Mean time from transplantation to EVAR was 7.5 (range, 2–12) years. Five underwent preoperative planning with noncontrast modalities only. Devices used included bifurcated (n = 3), aortouniiliac (n = 2), and tube (n = 1) stent grafts. Technical success was achieved in all patients. None experienced deterioration in renal function. Median follow-up was 39 (range, 6–51) months. Four patients were alive at the time of the study. Two patients expired during the period of follow-up from unrelated causes.ConclusionsEVAR is an effective modality for the management of AAAs in the coexistence of a transplanted kidney. It can be performed with minimal morbidity and mortality without harming the transplanted kidney. Special consideration should be given to device configuration to minimize damage to the renal graft

Endovascular Repair of Abdominal Aortic Aneurysms in the Presence of a Transplanted Kidney

Energy Technology Data Exchange (ETDEWEB)

Silverberg, Daniel, E-mail: silverberg-d@msn.com; Yalon, Tal; Halak, Moshe [The Chaim Sheba Medical Center, The Department of Vascular Surgery (Israel)

2015-08-15

PurposeTo present our experience performing endovascular repair of abdominal aortic aneurysms in kidney transplanted patients.MethodsA retrospective review of all patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA) performed at our institution from 2007 to 2014. We identified all patients who had previously undergone a kidney transplant. Data collected included: comorbidities, preoperative imaging modalities, indication for surgery, stent graft configurations, pre- and postoperative renal function, perioperative complications, and survival rates.ResultsA total of 267 EVARs were performed. Six (2 %) had a transplanted kidney. Mean age was 74 (range, 64–82) years; five were males. Mean time from transplantation to EVAR was 7.5 (range, 2–12) years. Five underwent preoperative planning with noncontrast modalities only. Devices used included bifurcated (n = 3), aortouniiliac (n = 2), and tube (n = 1) stent grafts. Technical success was achieved in all patients. None experienced deterioration in renal function. Median follow-up was 39 (range, 6–51) months. Four patients were alive at the time of the study. Two patients expired during the period of follow-up from unrelated causes.ConclusionsEVAR is an effective modality for the management of AAAs in the coexistence of a transplanted kidney. It can be performed with minimal morbidity and mortality without harming the transplanted kidney. Special consideration should be given to device configuration to minimize damage to the renal graft.

Multiple intracranial aneurysms following radiation therapy for pituitary adenoma. Case report

Energy Technology Data Exchange (ETDEWEB)

Nishi, Tohru; Matsukado, Yasuhiko; Kodama, Takafumi; Hiraki, Toshiro

1987-03-01

A 57-year-old man was admitted because of visual disturbance due to a recurrent pituitary adenoma. Nine years ago craniotomy was performed for the chromophobe adenoma and postoperative radiation therapy was applied with tumor dose of 50 Gy. Digital subtraction angiography indicated existence of an aneurysm at the carotid bifurcation and the finding was confirmed by conventional angiography, which revealed a saccular aneurysm and irregularity of the carotid walls. In surgery there were not only the saccular aneurysm found in the angiogram, but also three other fusiform aneurysms and severe sclerotic change at the major arteries adjoining the sellar region. Azzarelli et al. reported a fatal case due to the development of arteriosclerotic intracranial fusiform aneurysms following radiation therapy for suprasellar germinoma. This case is the second case which indicates the development of intracranial aneurysm following radiation therapy. Emphasis is placed on careful follow-up examination for radiated pituitary adenoma with computed tomography, digital subtraction angiography, or occasionally conventional angiography, even though the postoperative condition of the primary lesion is stabilized.

Fabrication of rigid and flexible refractive-index-matched flow phantoms for flow visualisation and optical flow measurements

Science.gov (United States)

Geoghegan, P. H.; Buchmann, N. A.; Spence, C. J. T.; Moore, S.; Jermy, M.

2012-05-01

A method for the construction of both rigid and compliant (flexible) transparent flow phantoms of biological flow structures, suitable for PIV and other optical flow methods with refractive-index-matched working fluid is described in detail. Methods for matching the in vivo compliance and elastic wave propagation wavelength are presented. The manipulation of MRI and CT scan data through an investment casting mould is described. A method for the casting of bubble-free phantoms in silicone elastomer is given. The method is applied to fabricate flexible phantoms of the carotid artery (with and without stenosis), the carotid artery bifurcation (idealised and patient-specific) and the human upper airway (nasal cavity). The fidelity of the phantoms to the original scan data is measured, and it is shown that the cross-sectional error is less than 5% for phantoms of simple shape but up to 16% for complex cross-sectional shapes such as the nasal cavity. This error is mainly due to the application of a PVA coating to the inner mould and can be reduced by shrinking the digital model. Sixteen per cent variation in area is less than the natural patient to patient variation of the physiological geometries. The compliance of the phantom walls is controlled within physiologically realistic ranges, by choice of the wall thickness, transmural pressure and Young's modulus of the elastomer. Data for the dependence of Young's modulus on curing temperature are given for Sylgard 184. Data for the temperature dependence of density, viscosity and refractive index of the refractive-index-matched working liquid (i.e. water-glycerol mixtures) are also presented.

Outcome after emergency surgery without angiography in patients with intracerebral haemorrhage after aneurysm rupture

DEFF Research Database (Denmark)

Bergdal, Ove; Springborg, Jacob; Hauerberg, John

2009-01-01

BACKGROUND: Patients with large intracerebral haematomas (ICH) from aneurysm rupture often present in a poor clinical condition and have a poor prognosis. Time delay for preoperative angiography might in some cases be unappealing. We evaluated the outcome after immediate haematoma removal...... and aneurysm occlusion without preoperative angiography. METHODS: We retrospectively identified 13 consecutive patients. We recorded clinical data and evaluated mortality and morbidity with the Glasgow Outcome Score (GOS) and Telephone Interview of Cognitive Status (TICS). FINDINGS: At follow up seven...... of thirteen patients had favourable outcome assessed by GOS. Three patients had severe disability and three patients died. None of the survived patients interviewed had impaired cognition. CONCLUSIONS: In patients presented in a critical state with aneurysmal ICH, emergency haematoma removal and aneurysm...

Microsurgical treatment of carotid-ophthalmic aneurysm associated with multiple anterior and posterior circulation aneurysms

Science.gov (United States)

Wang, Jiantao; Kan, Zhisheng; Wang, Shuo

2017-01-01

Abstract Background: The clipping of multiple intracranial aneurysms in 1 stage is uncommon. In this case, we report clipping of an ophthalmic aneurysm associated with multiple anterior and posterior circulation aneurysms via the Dolenc approach. Methods: The main symptoms of the patient are headache, along with nausea and vomiting. The patient's arteriogram revealed a wide-necked aneurysm of the right ophthalmic artery, an irregular aneurysm of the anterior communicating artery, and a basilar artery aneurysm. The surgical intervention for these aneurysms is a challenge because of the complex anatomical relationship with the surrounding structures. The 3 aneurysms, which were not amenable to a single intervention, were successfully clipped in 1 incision. Results: After surgery, the patient reported feeling well. One year after surgery, the patient had no SAH recurrence. Conclusions: Occasionally, surgical treatment was used even for aneurysms of the carotid-ophthalmic artery with aneurysms of anterior communicating artery and basilar artery, which are contraindicated for interventional therapy. PMID:28422878

Phantom motor execution facilitated by machine learning and augmented reality as treatment for phantom limb pain: a single group, clinical trial in patients with chronic intractable phantom limb pain.

Science.gov (United States)

Ortiz-Catalan, Max; Guðmundsdóttir, Rannveig A; Kristoffersen, Morten B; Zepeda-Echavarria, Alejandra; Caine-Winterberger, Kerstin; Kulbacka-Ortiz, Katarzyna; Widehammar, Cathrine; Eriksson, Karin; Stockselius, Anita; Ragnö, Christina; Pihlar, Zdenka; Burger, Helena; Hermansson, Liselotte

2016-12-10

Phantom limb pain is a debilitating condition for which no effective treatment has been found. We hypothesised that re-engagement of central and peripheral circuitry involved in motor execution could reduce phantom limb pain via competitive plasticity and reversal of cortical reorganisation. Patients with upper limb amputation and known chronic intractable phantom limb pain were recruited at three clinics in Sweden and one in Slovenia. Patients received 12 sessions of phantom motor execution using machine learning, augmented and virtual reality, and serious gaming. Changes in intensity, frequency, duration, quality, and intrusion of phantom limb pain were assessed by the use of the numeric rating scale, the pain rating index, the weighted pain distribution scale, and a study-specific frequency scale before each session and at follow-up interviews 1, 3, and 6 months after the last session. Changes in medication and prostheses were also monitored. Results are reported using descriptive statistics and analysed by non-parametric tests. The trial is registered at ClinicalTrials.gov, number NCT02281539. Between Sept 15, 2014, and April 10, 2015, 14 patients with intractable chronic phantom limb pain, for whom conventional treatments failed, were enrolled. After 12 sessions, patients showed statistically and clinically significant improvements in all metrics of phantom limb pain. Phantom limb pain decreased from pre-treatment to the last treatment session by 47% (SD 39; absolute mean change 1·0 [0·8]; p=0·001) for weighted pain distribution, 32% (38; absolute mean change 1·6 [1·8]; p=0·007) for the numeric rating scale, and 51% (33; absolute mean change 9·6 [8·1]; p=0·0001) for the pain rating index. The numeric rating scale score for intrusion of phantom limb pain in activities of daily living and sleep was reduced by 43% (SD 37; absolute mean change 2·4 [2·3]; p=0·004) and 61% (39; absolute mean change 2·3 [1·8]; p=0·001), respectively. Two of four

Anatomic characteristics and natural history of renal artery aneurysms during longitudinal imaging surveillance.

Science.gov (United States)

Wayne, Erik J; Edwards, Matthew S; Stafford, Jeanette M; Hansen, Kimberley J; Corriere, Matthew A

2014-08-01

Renal artery aneurysms (RAAs) are uncommon, and rates of growth and rupture are unknown. Limited evidence therefore exists to guide clinical management of RAAs, particularly small aneurysms that are asymptomatic. To further characterize the natural history of RAAs, we studied anatomic characteristics and changes in diameter during imaging surveillance. Patients evaluated for native RAAs at a single institution during a 5-year period (July 2008 to July 2013) were identified and analyzed retrospectively. Patients with two or more cross-sectional imaging studies (computed tomography or magnetic resonance imaging) more than 1 month apart were included. Demographic and clinical data were collected from medical records, and anatomic data (including aneurysm diameter, calcification, and location) were obtained from electronic images. Changes in RAA diameters over time were evaluated by plots and Wilcoxon signed rank tests. Sixty-eight RAAs in 55 patients were analyzed. Median follow-up was 19.4 months (interquartile range, 11.2-49.0 months). Mean age at presentation was 61.8 ± 9.8 years, and 73% of patients were women. Hypertension was prevalent among 73% of patients. Multiple RAAs were present in 18% of patients, and 24% also had arterial aneurysms of other splanchnic or iliac vessels. The majority of RAAs were calcified and located at the main renal artery bifurcation. Mean initial aneurysm diameter was 16.0 ± 6.4 mm. Median annualized growth rate was 0.06 mm (interquartile range, -0.07 to 0.33 mm; P = .11). No RAA ruptures or acute symptoms occurred during surveillance, and 10.3% of RAAs were repaired electively. Risk of short-term RAA growth or rupture was low. These findings suggest that annual (or less frequent) imaging surveillance is safe in the majority of patients and do not support pre-emptive repair of asymptomatic, small-diameter RAAs. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Coronary artery aneurysms

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Koischwitz, D.; Harder, T.; Schuppan, U.; Thurn, P.

1982-04-01

Seven saccular coronary artery aneurysms have been demonstrated in the course of 1452 selective coronary artery angiograms. In six patients they were arterio-sclerotic; in one patient the aneurysm must have been congenital or of mycotic-embolic origin. The differential diagnosis between true aneurysms and other causes of vascular dilatation is discussed. Coronary artery aneurysms have a poor prognosis because of the possibility of rupture with resultant cardiac tamponade, or the development of thrombo-embolic myocardial infarction. These aneurysms can only be diagnosed by means of coronary angiography and require appropriate treatment.

Endovascular treatment of the subclavian artery aneurysm in high-risk patient - a single-center experience

Directory of Open Access Journals (Sweden)

Marjanović Ivan

2016-01-01

Full Text Available We present our first experience with endovascular treatment of 6 subclavian artery aneurysms (SAA occurring in five male and one female patient. All patients, in our studies, according to ASA classification were high risk for open repair of SAA. The etiology of the all aneurysms was atherosclerosis degeneration of the artery. Two aneurysms were of intrathoracic location, then the other were extrathoracic. Symptoms related to subclavian artery aneurysms were present in two patients, compression and chest pain in one, and hemorrhage shock in second, while the remaining patients were asymptomatic. We preferred the Viabhan endoprosthesis for endovascular repair in 5 cases. In one patient with ruptured of subclavian artery aneurysm who was high-risk for open repair we made combined endovascular procedure. First at all, we covered the origin of left subclavian artery with thoracic stent graft and after that we put two coils in proximal part of subclavian artery. There was no operative mortality, and the early patency rate was 100%. The follow-up period was from 3 months to 3 years. During this period, one patient died of heart failure and one patient required endovascular reoperation due to endoleak type I. Endovascular treatment is recommended for all patients with subclavian artery aneurysm whenever this is possible due to anatomical reasons especially in high-risk patient with intrathoracic localization of aneurysm, to prevent potential complications.

Verification of Accuracy of CyberKnife Tumor-tracking Radiation Therapy Using Patient-specific Lung Phantoms

International Nuclear Information System (INIS)

Jung, Jinhong; Song, Si Yeol; Yoon, Sang Min; Kwak, Jungwon; Yoon, KyoungJun; Choi, Wonsik; Jeong, Seong-Yun; Choi, Eun Kyung; Cho, Byungchul

2015-01-01

Purpose: To investigate the accuracy of the CyberKnife Xsight Lung Tracking System (XLTS) compared with that of a fiducial-based target tracking system (FTTS) using patient-specific lung phantoms. Methods and Materials: Three-dimensional printing technology was used to make individualized lung phantoms that closely mimicked the lung anatomy of actual patients. Based on planning computed tomographic data from 6 lung cancer patients who underwent stereotactic ablative radiation therapy using the CyberKnife, the volume above a certain Hounsfield unit (HU) was assigned as the structure to be filled uniformly with polylactic acid material by a 3-dimensional printer (3D Edison, Lokit, Korea). We evaluated the discrepancies between the measured and modeled target positions, representing the total tracking error, using 3 log files that were generated during each treatment for both the FTTS and the XLTS. We also analyzed the γ index between the film dose measured under the FTTS and XLTS. Results: The overall mean values and standard deviations of total tracking errors for the FTTS were 0.36 ± 0.39 mm, 0.15 ± 0.64 mm, and 0.15 ± 0.62 mm for the craniocaudal (CC), left–right (LR), and anteroposterior (AP) components, respectively. Those for the XLTS were 0.38 ± 0.54 mm, 0.13 ± 0.18 mm, and 0.14 ± 0.37 mm for the CC, LR, and AP components, respectively. The average of γ passing rates was 100% for the criteria of 3%, 3 mm; 99.6% for the criteria of 2%, 2 mm; and 86.8% for the criteria of 1%, 1 mm. Conclusions: The XLTS has segmentation accuracy comparable with that of the FTTS and small total tracking errors

Verification of Accuracy of CyberKnife Tumor-tracking Radiation Therapy Using Patient-specific Lung Phantoms

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Jung, Jinhong [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Department of Radiation Oncology, Kyung Hee University Medical Center, Kyung Hee University School of Medicine, Seoul (Korea, Republic of); Song, Si Yeol, E-mail: coocoori@gmail.com [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Yoon, Sang Min; Kwak, Jungwon; Yoon, KyoungJun [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Wonsik [Department of Radiation Oncology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung (Korea, Republic of); Jeong, Seong-Yun [Asan Institute for Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Eun Kyung; Cho, Byungchul [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

2015-07-15

Purpose: To investigate the accuracy of the CyberKnife Xsight Lung Tracking System (XLTS) compared with that of a fiducial-based target tracking system (FTTS) using patient-specific lung phantoms. Methods and Materials: Three-dimensional printing technology was used to make individualized lung phantoms that closely mimicked the lung anatomy of actual patients. Based on planning computed tomographic data from 6 lung cancer patients who underwent stereotactic ablative radiation therapy using the CyberKnife, the volume above a certain Hounsfield unit (HU) was assigned as the structure to be filled uniformly with polylactic acid material by a 3-dimensional printer (3D Edison, Lokit, Korea). We evaluated the discrepancies between the measured and modeled target positions, representing the total tracking error, using 3 log files that were generated during each treatment for both the FTTS and the XLTS. We also analyzed the γ index between the film dose measured under the FTTS and XLTS. Results: The overall mean values and standard deviations of total tracking errors for the FTTS were 0.36 ± 0.39 mm, 0.15 ± 0.64 mm, and 0.15 ± 0.62 mm for the craniocaudal (CC), left–right (LR), and anteroposterior (AP) components, respectively. Those for the XLTS were 0.38 ± 0.54 mm, 0.13 ± 0.18 mm, and 0.14 ± 0.37 mm for the CC, LR, and AP components, respectively. The average of γ passing rates was 100% for the criteria of 3%, 3 mm; 99.6% for the criteria of 2%, 2 mm; and 86.8% for the criteria of 1%, 1 mm. Conclusions: The XLTS has segmentation accuracy comparable with that of the FTTS and small total tracking errors.

Risk of rupture of unruptured cerebral aneurysms in elderly patients

OpenAIRE

Hishikawa, Tomohito; Date, Isao; Tokunaga, Koji; Tominari, Shinjiro; Nozaki, Kazuhiko; Shiokawa, Yoshiaki; Houkin, Kiyohiro; Murayama, Yuichi; Ishibashi, Toshihiro; Takao, Hiroyuki; Kimura, Toshikazu; Nakayama, Takeo; Morita, Akio

2015-01-01

Objectives: The aim of this study was to identify risk factors for rupture of unruptured cerebral aneurysms (UCAs) in elderly Japanese patients aged 70 years or older. Methods: The participants included all patients 70 years of age or older in 3 prospective studies in Japan (the Unruptured Cerebral Aneurysm Study of Japan [UCAS Japan], UCAS II, and the prospective study at the Jikei University School of Medicine). A total of 1,896 patients aged 70 years or older with 2,227 UCAs were investiga...

Retrospective review of cerebral mycotic aneurysms in 26 patients: focus on treatment in strongly immunocompromised patients with a brief literature review.

Science.gov (United States)

Allen, L M; Fowler, A M; Walker, C; Derdeyn, C P; Nguyen, B V; Hasso, A N; Ghodke, B V; Zipfel, G J; Cross, D T; Moran, C J

2013-04-01

Cerebral mycotic aneurysms are a rare and deadly type of aneurysm that have no definitive treatment guidelines. Our purpose was to retrospectively review known or suspected cases of CMA in order to identify patient populations that may be associated with higher morbidity and mortality. We hope that the identification of patients with these risk factors will lead to early stratification upon presentation, and more urgent treatment of their CMAs. We also hoped to identify any benefit or complication that was specific to either the endovascular or neurosurgical repair of CMAs. A retrospective multi-institutional study was performed examining cases of CMA during a 15-year period. Patients were considered strongly immunocompromised if there were long-term severely immunocompromised states: AIDS, chemotherapy, or steroid immunosuppression. Patients were excluded if angiographic findings suggested an alternative diagnosis or if an infectious etiology was unknown. Antibiotics were considered "noninvasive treatment." Endovascular and neurosurgical repair were considered "invasive treatment." Data were recorded by reviewing electronic medical records and imaging reports. Twenty-six patients with 40 CMAs were included. Three patients were considered strongly immunocompromised and presented with 4 CMAs, which demonstrated larger average size and more rapid growth; 3 of these patients' aneurysms were treated invasively in the acute period, with the one that was not ruptured causing death. Technical success (aneurysm occlusion without rupture or recanalization) and clinical success (no neurologic complication attributable to the intervention) were obtained equally endovascularly and neurosurgically. Clipping was aborted in favor of coiling for 1 patient. Anticoagulation needed reversal before 2 patients underwent craniotomy for clipping after valve replacement. For CMAs treated with antibiotics alone with angiographic follow-up (n=11), initial aneurysm size was unrelated to

Development of mathematical phantoms for calculating internal doses from radiopharmaceuticals using patients' digital picture of bone scintillation

International Nuclear Information System (INIS)

Akahane, K.; Kai, M.; Kusama, T.

1996-01-01

We made a new mathematical phantom using the patients' digital pictures of bone scintillation in nuclear medicine. The data of 99m Tc bone scintillation pictures include the information on the body sizes and shapes. In the bone scintillation pictures, no three dimensional data are available, so that the shapes and sizes of whole body and bones were modelled based on standard anatomical geometry. The organs except bone were also modelled after construction of the bone mathematical model. The mathematical phantoms were developed for each patient. The specific effective energy for each phantom can be calculated by the Monte Carlo code to compare it among the patients. Our mathematical phantoms would provide new calculation of internal doses from radiopharmaceuticals in place of the MIRD phantom. (author)

Association Between Vascular Anatomy and Posterior Communicating Artery Aneurysms.

Science.gov (United States)

Can, Anil; Ho, Allen L; Emmer, Bart J; Dammers, Ruben; Dirven, Clemens M F; Du, Rose

2015-11-01

Hemodynamic stress, conditioned by the geometry and morphology of the vessel trees, plays an important role in the formation of intracranial aneurysms. The aim of this study was to identify image-based location-specific morphologic parameters that are associated with posterior communicating artery (PCoA) aneurysms. Morphologic parameters obtained from computed tomography angiography of 56 patients with PCoA aneurysms and 23 control patients were evaluated with 3D Slicer, an open-source image analysis software, to generate 3-dimensional models of the aneurysms and surrounding vasculature. Segment lengths, diameters, and vessel-to-vessel angles were examined. To control for genetic and clinical risk factors, the unaffected contralateral side of patients with unilateral PCoA aneurysms was used as a control group for internal carotid artery (ICA)-related parameters. A separate control group with visible PCoAs and aneurysms elsewhere was used as a control group for PCoA-related parameters. Internal carotid artery-related parameters were not statistically different between the PCoA aneurysm and control groups. Univariate and multivariate subgroup analysis for patients with visualized PCoAs demonstrated that a larger PCoA diameter was significantly associated with the presence of a PCoA aneurysm (odds ratio = 12.1, 95% confidence interval = 1.3-17.1, P = 0.04) after adjusting for other morphologic parameters. Larger PCoA diameters are associated with the presence of PCoA aneurysms. These parameters may provide objective metrics to assess aneurysm formation and growth risk stratification in high-risk patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Treatment of Visceral Aneurysm Using Multilayer Stent: Two-Year Follow-Up Results in Five Consecutive Patients

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Balderi, Alberto, E-mail: balders@libero.it; Antonietti, Alberto, E-mail: antonietti.a@ospedale.cuneo.it; Pedrazzini, Fulvio, E-mail: pedrazzini.f@ospedale.cuneo.it; Sortino, Davide, E-mail: davide.sortino@hotmail.it; Vinay, Claudia, E-mail: claudia.vinay@gmail.com; Grosso, Maurizio, E-mail: grosso.m@ospedale.cuneo.it [AO Santa Croce e Carle Hospital, Department of Radiology (Italy)

2013-10-15

Purpose: The present study was performed to analyze the midterm results (five consecutive patients, 2-year follow-up) of the endovascular management of visceral artery aneurysms using the Cardiatis Multilayer Flow Modulator (CMFM) (Cardiatis, Isnes, Belgium), a self-expandable stent. Materials and Methods: From August 2009 to January 2011, we implanted five CMFMs in five patients (all men; mean age 73 years) to treat two common hepatic artery aneurysms, one celiac trunk aneurysm, one splenic artery aneurysm, and one superior mesenteric artery aneurysm (diameter 25-81 mm). The primary end point was technical success. The secondary end point was stent patency, absence of aneurysm rupture or reperfusion, and shrinking of the sac at 6-, 12-, and 24-month follow-up using computed tomography angiography. Follow-up ranged from 24 to 48 months (mean 31.2). Results: Technical success was achieved in all patients. Complete exclusion of the aneurysm with sac shrinking was achieved in two patients. Two stents became occluded at 6- and 24-month follow-up, respectively; both patients were asymptomatic and were not retreated. One patient developed sac reperfusion due to incomplete aneurysm exclusion. Conclusion: Long-term results in a wider population are needed to validate the effectiveness of the CMFM.

A case of acute subdural hematoma due to ruptured aneurysm detected by postmortem angiography.

Science.gov (United States)

Inokuchi, Go; Makino, Yohsuke; Yajima, Daisuke; Motomura, Ayumi; Chiba, Fumiko; Torimitsu, Suguru; Hoshioka, Yumi; Iwase, Hirotaro

2016-03-01

Acute subdural hematoma (ASDH) is mostly caused by head trauma, but intrinsic causes also exist such as aneurysm rupture. We describe here a case involving a man in his 70s who was found lying on the bedroom floor by his family. CT performed at the hospital showed ASDH and a forensic autopsy was requested. Postmortem cerebral angiography showed dilatation of the bifurcation of the middle cerebral artery, which coincided with the dilated part of the Sylvian fissure. Extravasation of contrast medium into the subdural hematoma from this site was suggestive of a ruptured aneurysm. Autopsy revealed a fleshy hematoma (total weight 110 g) in the right subdural space and findings of brain herniation. As indicated on angiography, a ruptured saccular aneurysm was confirmed at the bifurcation of the middle cerebral artery. Obvious injuries to the head or face could not be detected on either external or internal examination, and intrinsic ASDH due to a ruptured middle cerebral artery aneurysm was determined as the cause of death. One of the key points of forensic diagnosis is the strict differentiation between intrinsic and extrinsic onset for conditions leading to death. Although most subdural hematomas (SDH) are caused by extrinsic factors, forensic pathologists should consider the possibility of intrinsic SDH. In addition, postmortem angiography can be useful for identifying vascular lesions in such cases.

Radiological equipment analyzed by specific developed phantoms and software

International Nuclear Information System (INIS)

Soto, M.; Campayo, J. M.; Mayo, P.; Verdu, G.; Rodenas, F.

2010-10-01

The use of radiographic phantoms specifically designed to evaluate the operation of the radiographic equipment lets the study of the image quality obtained by this equipment in an objective way. In digital radiographic equipment, the analysis of the image quality can be computerized because the acquisition of the image is possible in different technologies that are, computerized radiography or phosphor plate and direct radiography or detector. In case of film-screen equipment s this analysis could be applied digitalising the image in a professional scanner. In this work we have shown an application to assess automatically the constancy quality image in the image chain of the radiographic equipment s. This application is integrated by designed radiographic phantoms which are adapted to conventional, dental equipment s and specific developed software for the automatic evaluation of the phantom image quality. The software is based on digital image processing techniques that let the automatic detection of the different phantom tests by edge detector, morphological operators, threshold histogram techniques... etc. The utility developed is enough sensitive to the radiographic equipment of operating conditions of voltage (kV) and charge (m As). It is a friendly user programme connected with a data base of the hospital or clinic where it has been used. After the phantom image processing the user can obtain an inform with a resume of the imaging system state with accepting and constancy results. (Author)

Radiological equipment analyzed by specific developed phantoms and software

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Soto, M.; Campayo, J. M. [Logistica y Acondicionamientos Industriales SAU, Sorolla Center, Local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain); Mayo, P. [TITANIA Servicios Tecnologicos SL, Sorolla Center, Local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain); Verdu, G.; Rodenas, F., E-mail: m.soto@lainsa.co [ISIRYIM Universidad Politecnica de Valencia, Camino de Vera s/n, Valencia (Spain)

2010-10-15

The use of radiographic phantoms specifically designed to evaluate the operation of the radiographic equipment lets the study of the image quality obtained by this equipment in an objective way. In digital radiographic equipment, the analysis of the image quality can be computerized because the acquisition of the image is possible in different technologies that are, computerized radiography or phosphor plate and direct radiography or detector. In case of film-screen equipment s this analysis could be applied digitalising the image in a professional scanner. In this work we have shown an application to assess automatically the constancy quality image in the image chain of the radiographic equipment s. This application is integrated by designed radiographic phantoms which are adapted to conventional, dental equipment s and specific developed software for the automatic evaluation of the phantom image quality. The software is based on digital image processing techniques that let the automatic detection of the different phantom tests by edge detector, morphological operators, threshold histogram techniques... etc. The utility developed is enough sensitive to the radiographic equipment of operating conditions of voltage (kV) and charge (m As). It is a friendly user programme connected with a data base of the hospital or clinic where it has been used. After the phantom image processing the user can obtain an inform with a resume of the imaging system state with accepting and constancy results. (Author)

A multiscale modelling approach to understand atherosclerosis formation: A patient-specific case study in the aortic bifurcation

Science.gov (United States)

Alimohammadi, Mona; Pichardo-Almarza, Cesar; Agu, Obiekezie; Díaz-Zuccarini, Vanessa

2017-01-01

Atherogenesis, the formation of plaques in the wall of blood vessels, starts as a result of lipid accumulation (low-density lipoprotein cholesterol) in the vessel wall. Such accumulation is related to the site of endothelial mechanotransduction, the endothelial response to mechanical stimuli and haemodynamics, which determines biochemical processes regulating the vessel wall permeability. This interaction between biomechanical and biochemical phenomena is complex, spanning different biological scales and is patient-specific, requiring tools able to capture such mathematical and biological complexity in a unified framework. Mathematical models offer an elegant and efficient way of doing this, by taking into account multifactorial and multiscale processes and mechanisms, in order to capture the fundamentals of plaque formation in individual patients. In this study, a mathematical model to understand plaque and calcification locations is presented: this model provides a strong interpretability and physical meaning through a multiscale, complex index or metric (the penetration site of low-density lipoprotein cholesterol, expressed as volumetric flux). Computed tomography scans of the aortic bifurcation and iliac arteries are analysed and compared with the results of the multifactorial model. The results indicate that the model shows potential to predict the majority of the plaque locations, also not predicting regions where plaques are absent. The promising results from this case study provide a proof of concept that can be applied to a larger patient population. PMID:28427316

Dissecting aortic aneurysm in maintenance hemodialysis patients

Directory of Open Access Journals (Sweden)

Ounissi M

2009-01-01

Full Text Available The dissecting aortic aneurysm (DAA is a rare pathology that may result in fatal outcome. We report follow up of three cases of DAA patients undergoing maintenance hemo-dialysis who were managed conservatively.

[Analysis on Clinical Characteristic and Risk Factors of Patients Coexistence of Cerebral Artery Stenosis with Unruptured Intracranial Aneurysm].

Science.gov (United States)

Zhao, Hai-Yan; Han, Jin-Tao; Fan, Dong-Sheng

2017-09-01

To analyze the incidence of intracranial unruptured aneurysms in patients with intracranial artery stenosis,clinical features,and investigate the risk factors for unruptured intracranial aneurysms. Medical records from all patients performed with digital subtraction angiography (DSA) who had been treated at Peking University Third Hospital,China,from January 2012 to December 2015 were retrospectively reviewed to identify cases coexistence with cerebral artery stenosis and unruptured intracranial aneurysm. Of 273 patients with cerebral artery stenosis (≥50%),intracranial unruptured aneurysms was observed in 17 cases (6.23%) from age of 45 to 78,among them 8 (47.06%) were female and 9 (52.94%) were male. The incidence of unruptured intracranial aneurysm in male patients was 4.17% (9/216),and that of female was 14.4% (8/57). There was statistically significant difference between the male and female incidence of intracranial aneurysm ( P patients,16 (94.12%) aneurysms were located in the internal carotid artery (ICA) system,1 (5.88%) aneurysm was located at the tip of the basilar artery. In 11 cases (64.71%),aneurysms were located at the distal of the stenotic vessels,2 (11.76%) were located at the proximal of the stenotic vessels,and 4 cases (23.53%) of which the aneurysm and stenosis were not in the same artery. Logistic multivariate analysis showed that gender was an independent risk factor for aneurysms in patients with cerebral arterial stenosis. In the intracranial artery stenosis atients,the possibility of the occurrence of the aneurysm is much higher than the general population,and women were more prominent than man. Sex is an independent risk factor for aneurysms in patients with cerebral arterial stenosis.

Epidemiologic and Demographic Features, Therapeutic Intervention and Prognosis of the Patients with Cerebral Aneurysm

Directory of Open Access Journals (Sweden)

Masih Sabouri

2018-01-01

Full Text Available Background: Cerebral aneurysms are a kind of cardiovascular diseases which are accompanied with high morbidity and mortality due to rupturing and causing subarachnoid hemorrhages. The current study aimed to determine epidemiologic and demographic features and prognosis of patients with cerebral aneurysms. Materials and Methods: In this cross-sectional study, 465 patients with cerebral aneurysms hospitalized in Al-Zahra Hospital were studied. The required information including demographic, epidemiologic, and clinical features of the disease were extracted from their records. The obtained data were analyzed using SPSS software and the factors associated with the prognosis of the disease were determined. Results: Four hundred and sixty-five cases with cerebral aneurysm undergoing surgery were investigated. The mean age of the patients was 48 ± 14 years whereas 216 cases (46.5% were male and 249 (53.5% were female. Two hundred and thirty-seven patients (51% remitted completely while the disease caused moderate disability in 84 cases (18.1%, severe disability in 24 ones (5.2% and vegetative state in 9 cases (1.9% and mortality in 57 ones while it was unknown in 54 cases (11.6%. In terms of the age of patient, WFNS index, anatomical position of aneurysm, type of aneurysm lesion, the incidence season of the disease, type of postoperative complications, family history and operative approach, the disease outcome had a significant difference while gender, ethnicity, and risk factors had no significant effect on the disease outcome. Conclusions: According to the type of aneurysm, the incidence position of the aneurysm and other epidemiologic, demographic, and clinical features, providing the prevention and treatment strategies is necessary.

Morphological and clinical risk factors for posterior communicating artery aneurysm rupture.

Science.gov (United States)

Matsukawa, Hidetoshi; Fujii, Motoharu; Akaike, Gensuke; Uemura, Akihiro; Takahashi, Osamu; Niimi, Yasunari; Shinoda, Masaki

2014-01-01

Recent studies have shown that posterior circulation aneurysms, specifically posterior communicating artery (PCoA) aneurysms, are more likely to rupture than other aneurysms. To date, few studies have investigated the factors contributing to PCoA aneurysm rupture. The authors aimed to identify morphological and clinical characteristics predisposing to PCoA aneurysm rupture. The authors retrospectively reviewed 134 consecutive patients with PCoA aneurysms managed at their facility between July 2003 and December 2012. The authors divided patients into groups of those with aneurysmal rupture (n = 39) and without aneurysmal rupture (n = 95) and compared morphological and clinical characteristics. Morphological characteristics were mainly evaluated by 3D CT angiography and included diameter of arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery), size of the aneurysm, dome-to-neck ratio, neck direction of the aneurysmal dome around the PCoA (medial, lateral, superior, inferior, and posterior), aneurysm bleb formation, whether the PCoA was fetal type, and the existence of other intracranial unruptured aneurysm(s). Patients with ruptured PCoA aneurysms were significantly younger (a higher proportion were PCoA aneurysms showed a lateral direction of the aneurysmal dome around the PCoA, had bleb formation, and the aneurysm was > 7 mm in diameter and/or the dome-to-neck ratio was > 2.0. Multivariate logistic regression analysis showed age PCoA (OR 6.7, p = 0.0001), and bleb formation (OR 11, p PCoA aneurysm rupture. The present results demonstrated that lateral projection of a PCoA aneurysm may be related to rupture.

[Re-bleeding predictors in patients with aneurysmal subarachnoid haemorrhage and delayed neurosurgical treatment].

Science.gov (United States)

Rivero Rodríguez, Dannys; Scherle Matamoros, Claudio; Fernández Cúe, Leda; Miranda Hernández, José Luis; Pernas Sánchez, Yanelis; Pérez Nellar, Jesús

2016-01-01

To evaluate the re-bleeding predictors in patients with delayed treatment of aneurysmal subarachnoid hemorrhage. A prospective cohort study enrolled 261 patients with aneurysmal subarachnoid hemorrhage, attending in Hermanos Ameijeiras Hospital from October 2005, and June 2014. An increased re-bleeding risk in the multivariate analysis was associated with grade III (OR 2.01; 95% CI; 1.06-3.84) and grade IV (OR 3.84; 95% CI; 2.06-7.31) on World Federation Neurological Surgeon (WFNS) scale; grade III (OR 2.04; 95% CI; 1.01-4.13) and grade IV (OR 2.12, 95% CI; 1.05-4.28) on the Fischer scale, aneurism location in posterior circulation (OR 2.45, 95% CI; 1.33-4.44), and anterior communicant artery (OR 1.57, 95% CI;1.00-2.46). Hypertension history was present in 60.9% (159 patients) and was also associated with risk of re-bleeding (OR 2.70, 95% CI; 1.00-7.30). Blood pressure, haematocrit, glycemic, aneurysm size, multiple aneurysms, and location in the middle cerebral artery, do not show any relationship. Hypertension history, poor grade (III and IV) on WFNS and Fisher scale and aneurysm location were independent risks factors of re-bleeding in patients with delayed aneurysmal treatment. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

CT findings of subarachnoid hemorrhage due to ruptured cerebral aneurysm

International Nuclear Information System (INIS)

Kim, Pyo Nyun; Bae, Won Kyung; Kim, Il Young; Lee, Kyung Soo; Lee, Byoung Ho; Kim, Ki Jung

1990-01-01

CT scans were analysed retrospectively in 130 patients with subarachnoid hemorrhage (SAH) due to ruptured cerebral aneurysm to evaluate the relationship of the locations of aneurysms and the patterns of hemorrhage. Hemorrhage corresponded to the site of aneurysmal origin in a general way and in more specific ways to anterior communicating and middle cerebral artery aneurysms when there was parenchymal or cisternal hemorrhage. In anterior communicating artery aneurysm, SAH in the interhemispheric fissure, both sylvian fissures, and basal cistern was usually noted and intracerebral hemorrhage in anteroinferior frontal lobe was sometimes associated. In cases of middle cerebral artery aneurysm, hemorrhage in the ipsilateral sylvian fissure, interhemispheric fissure, and ipsilateral basal cistern was usual. Intracerebral hemorrhage in lateral temporal lobe was sometimes associated. Posterior communicating artery aneurysm demonstrated SAH in the ipsilateral basal cistern or in entire cisternal spaces specifically, so with higher incidence of involvement of the quadrigeminal and superior cerebellar cistern than anterior cerebral or middle cerebral artery aneurysm. We suggest the locations of aneurysm might be predicted with patterns of SAH and / or associated intracerebral hemorrhage with CT

Proteomic identification of differentially expressed proteins in aortic wall of patients with ruptured and nonruptured abdominal aortic aneurysms

DEFF Research Database (Denmark)

Urbonavicius, Sigitas; Lindholt, Jes S.; Vorum, Henrik

2009-01-01

To compare the basic proteomic composition of abdominal aortic aneurysm (AAA) wall tissue in patients with nonruptured and ruptured aneurysms.......To compare the basic proteomic composition of abdominal aortic aneurysm (AAA) wall tissue in patients with nonruptured and ruptured aneurysms....

MMP-2 Isoforms in Aortic Tissue and Serum of Patients with Ascending Aortic Aneurysms and Aortic Root Aneurysms

Science.gov (United States)

Tscheuschler, Anke; Meffert, Philipp; Beyersdorf, Friedhelm; Heilmann, Claudia; Kocher, Nadja; Uffelmann, Xenia; Discher, Philipp; Siepe, Matthias; Kari, Fabian A.

2016-01-01

Objective The need for biological markers of aortic wall stress and risk of rupture or dissection of ascending aortic aneurysms is obvious. To date, wall stress cannot be related to a certain biological marker. We analyzed aortic tissue and serum for the presence of different MMP-2 isoforms to find a connection between serum and tissue MMP-2 and to evaluate the potential of different MMP-2 isoforms as markers of high wall stress. Methods Serum and aortic tissue from n = 24 patients and serum from n = 19 healthy controls was analyzed by ELISA and gelatin zymography. 24 patients had ascending aortic aneurysms, 10 of them also had aortic root aneurysms. Three patients had normally functioning valves, 12 had regurgitation alone, eight had regurgitation and stenosis and one had only stenosis. Patients had bicuspid and tricuspid aortic valves (9/15). Serum samples were taken preoperatively, and the aortic wall specimen collected during surgical aortic repair. Results Pro-MMP-2 was identified in all serum and tissue samples. Pro-MMP-2 was detected in all tissue and serum samples from patients with ascending aortic/aortic root aneurysms, irrespective of valve morphology or other clinical parameters and in serum from healthy controls. We also identified active MMP-2 in all tissue samples from patients with ascending aortic/aortic root aneurysms. None of the analyzed serum samples revealed signals relatable to active MMP-2. No correlation between aortic tissue total MMP-2 or tissue pro-MMP-2 or tissue active MMP-2 and serum MMP-2 was found and tissue MMP-2/pro-MMP-2/active MMP-2 did not correlate with aortic diameter. This evidence shows that pro-MMP-2 is the predominant MMP-2 species in serum of patients and healthy individuals and in aneurysmatic aortic tissue, irrespective of aortic valve configuration. Active MMP-2 species are either not released into systemic circulation or not detectable in serum. There is no reliable connection between aortic tissue—and serum MMP-2

Factors responsible for poor outcome after intraprocedural rerupture of ruptured intracranial aneurysms: Identification of risk factors, prevention and management on 18 cases

International Nuclear Information System (INIS)

Zhang Xin; Long Xiaoao; Luo Bin; Karuna, Tamrakar; Duan Chuanzhi

2012-01-01

Purpose: The paper mainly involved the retrospective approach to risk factors of intraprocedual rerupture (IPR) and illustration of our empirical prevention and management on this event as well as its postembolization outcomes evaluation. Materials and methods: Endovascular treatment was performed in 1308 patients with 1308 ruptured intracranial aneurysms, and IPR occurred in 18 cases. We retrospectively reviewed their clinical records and images, and analysis risk factors of IPR by using multivariate logistic regression. Results: The morbidity of IPR was 1.38% and mortality was 33.33%. Nine patients survived from rapid completion of coiling with immediate reversal of heparin anticoagulation with protamine sulfate, and 3 from emergent external ventricular drainage (EVD). However, 9 of them presented with different degrees of disability and 3 were fully recovered. Small aneurysms (diameter ≤ 3.0 mm) (OR 284.212, 95% C.I. 17.368–4650.780, P = 0.000), atherosclerosis (OR 7.866, 95% C.I. 1.113–55.570, P = 0.039), Fisher Grade III (OR 82.099, 95% C.I. 1.563–431.696, P = 0.029), vasospasm (grade I) (OR 32.269, 95% C.I. 2.393–435.132, P = 0.009) and vasospasm (grade II) (OR 30.238, 95% C.I. 1.770–516.552, P = 0.019) are risk factors of IPR. Aneurysms at proximal part of internal carotid artery (ICA), bifurcation and basilar artery (BA) stem (OR 0.003, 95% C.I. 0.000–0.101, P = 0.001) and Hunt and Hess Grade II (OR 0.010, 95% C.I. 0.000–0.346, P = 0.011) are identified as protective factors. Conclusions: Small aneurysms, atherosclerosis, Fisher Grade of SAH and cerebral vasospasm are the predictors of IPR. Aneurysms at proximal part of ICA bifurcation and BA stem and Hunt and Hess Grade II are less associated with IPR. Rapid completion of coiling combined with immediate reversal of heparin anticoagulation is confirmed to be the best strategy in our series.

Multiple Vascular Accidents Including Rupture of a Sinus of Valsalva Aneurysm, a Minor Ischemic Stroke and Intracranial Arterial Anomaly in a Patient with Systemic Congenital Abnormalities: A Case Report

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Masataka Nakajima

2013-11-01

Full Text Available A 39-year-old man with a history of rupture of a sinus of Valsalva aneurysm experienced an ischemic stroke. Although the patient presented left-sided hemiparesis for a week, no abnormal signals were indicated on diffusion-weighted imaging with repeated magnetic resonance scans. Carotid ultrasound and cerebral angiography were conducted, and they revealed hypoplasty of the left internal carotid artery with a low-lying carotid bifurcation at the level of the C6 vertebra. In addition, he was diagnosed with intellectual disabilities, evaluated by the Wechsler Adult Intelligence Scale-III, and congenital velopharyngeal insufficiency. We herein present the first report of a patient with cardio-cerebrovascular abnormalities, intellectual disabilities, and an otorhinolaryngological abnormality.

Comparison of 16-row multislice CT angiography with conventional angiography for detection and evaluation of intracranial aneurysms

International Nuclear Information System (INIS)

Donmez, Halil; Serifov, Elman; Kahriman, Guven; Mavili, Ertugrul; Durak, Ahmet Candan; Menkue, Ahmet

2011-01-01

Purpose: The aim of this study is to compare the diagnostic performance of 16-row computed tomographic angiography (MDCTA) with digital subtraction angiography (DSA) for the detection and characterization of intracranial aneurysms in patients with nontraumatic subarachnoid hemorrhages (SAH). Materials and methods: One-hundred and twelve consecutive patients with suspected intracranial aneurysm underwent both 16-row MDCTA and DSA. The MDCT angiograms were interpreted in a blinded fashion by using combination with VRI, MIP and MPR techniques. Sensitivity specificity and accuracy were calculated for the CTA and DSA. The results were compared with each other. The DSA reader's interpretation was accepted as the reference standard. Results: A total of 164 aneurysms were detected at DSA in 112 patients, no aneurysms were detected by DSA and MDCTA in 16 patients. Eight aneurysms were missed by MDCTA. The overall sensitivity, specificity, and accuracy of MDCTA on a per-aneurysm basis were 95.1%, 94.1%, and 95%, respectively. According to the size of the aneurysm less than 3 mm; sensitivity, specificity and diagnostic accuracy of MDCTA were 86.1%, 94.1%, 88.6%, respectively. Conclusion: This study suggests that MDCTA is equally as sensitive as DSA in the detection of intracranial aneurysms of greater than 3 mm, and it also reveals 100% detection rate for ruptured aneurysms.

Phantom shocks in patients with implantable cardioverter defibrillator

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Berg, Selina Kikkenborg; Moons, Philip; Zwisler, Ann-Dorthe

2013-01-01

of phantom shocks.METHODS AND RESULTS: The design was secondary explorative analyses of data from a randomized controlled trial. One hundred and ninety-six patients with first-time ICD implantation (79% male, mean age 58 years) were randomized (1 : 1) to either combined rehabilitation or a control group...... questions regarding the experience of phantom shocks, date, time, and place. Twelve patients (9.4%) experienced a phantom shock, 7 in the intervention group and 5 in the control group (NS). Neither age, sex, quality of life nor perceived health at baseline was significantly related to the probability...

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms

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Lv, Nan; Wang, Chi; Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

2016-01-01

Background and Purpose The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. Materials and Methods In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemo...

Gender, smoking, body size, and aneurysm geometry influence the biomechanical rupture risk of abdominal aortic aneurysms as estimated by finite element analysis.

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Lindquist Liljeqvist, Moritz; Hultgren, Rebecka; Siika, Antti; Gasser, T Christian; Roy, Joy

2017-04-01

Finite element analysis (FEA) has been suggested to be superior to maximal diameter measurements in predicting rupture of abdominal aortic aneurysms (AAAs). Our objective was to investigate to what extent previously described rupture risk factors were associated with FEA-estimated rupture risk. One hundred forty-six patients with an asymptomatic AAA of a 40- to 60-mm diameter were retrospectively identified and consecutively included. The patients' computed tomography angiograms were analyzed by FEA without (neutral) and with (specific) input of patient-specific mean arterial pressure (MAP), gender, family history, and age. The maximal wall stress/wall strength ratio was described as a rupture risk equivalent diameter (RRED), which translated this ratio into an average aneurysm diameter of corresponding rupture risk. In multivariate linear regression, RRED neutral increased with female gender (3.7 mm; 95% confidence interval [CI], 0.13-7.3) and correlated with patient height (0.27 mm/cm; 95% CI, 0.11-0.43) and body surface area (BSA, 16 mm/m 2 ; 95% CI, 8.3-24) and inversely with body mass index (BMI, -0.40 mm/kg m -2 ; 95% CI, -0.75 to -0.054) in a wall stress-dependent manner. Wall stress-adjusted RRED neutral was raised if the patient was currently smoking (1.1 mm; 95% CI, 0.21-1.9). Age, MAP, family history, and patient weight were unrelated to RRED neutral . In specific FEA, RRED specific increased with female gender, MAP, family history positive for AAA, height, and BSA, whereas it was inversely related to BMI. All results were independent of aneurysm diameter. Peak wall stress and RRED correlated with aneurysm diameter and lumen volume. Female gender, current smoking, increased patient height and BSA, and low BMI were found to increase the mechanical rupture risk of AAAs. Previously described rupture risk factors may in part be explained by patient characteristic-dependent variations in aneurysm biomechanics. Copyright © 2016 Society for Vascular

The Use of Flow Diverting Stents to Treat Para-Ophthalmic Aneurysms

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Pervinder Bhogal

2017-08-01

Full Text Available Background and purposeFew publications have dealt exclusively with the use of flow diverter stents for the treatment of para-ophthalmic aneurysms. We sought to determine the efficacy of flow diverting stents (FDSs to treat aneurysms in this specific location.MethodsWe retrospectively reviewed our database of prospectively collected information for all patients treated with flow diversion for an unruptured saccular para-ophthalmic aneurysm between September 2009 and January 2016. The aneurysm fundus size, neck size, number and type of FDS, complications, and follow-up data were recorded.ResultsWe identified 74 patients that matched our inclusion criteria. Of these patients, 18 patients were male (24.3%. The average fundus size was 4.8 mm, 11 aneurysms had previous coil occlusions and 63 were treated solely with flow diversion. At an initial angiographic follow-up (mean avg. 3.2 months, 71.8% of the aneurysms were occluded, and at the last follow-up (mean avg. 31.8 months, 88.9% of aneurysms were occluded. One patient suffered permanent morbidity (1.36% secondary to interruption of the antiplatelet medication and another died (1.36% secondary to in-stent thrombosis that was also due to an interruption in the antiplatelet medication.ConclusionTreatment of saccular para-ophthalmic aneurysms with FDS is feasible and carries a high degree of technical success with low complication rates and excellent rates of aneurysm exclusion.

Aneurysmal Subarachnoid Hemorrhage

Science.gov (United States)

2015-01-01

Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome. PMID:25272066

Correlation between the clinical presentation and DSA of intracranial aneurysms

International Nuclear Information System (INIS)

Fang Chun; Hua Jia; Chen Kemin; Yin Yan; Ge Xin; Ying Yiping

2001-01-01

Objective: To evaluate the correlation between the clinical presentation and cerebral angiographic features of intracranial aneurysms. Methods: The authors retrospectively analyzed the relationship between the size, location and shape of 48 patient's cerebral aneurysms and their clinical presentations. Results: Clinical symptoms of cerebral aneurysms were related with their size, location and shape. Aneurysms in different location or at same location may cause similar symptoms or different symptoms. Rotation DSA is a useful examination supplemented to conventional DSA. Conclusions: The relationship between the location and the presentation of intracranial aneurysms is not specific. Rotation DSA plays important role in showing the characteristics of the cerebral aneurysms

Perioperative management of endovascular abdominal aortic aneurysm repair

International Nuclear Information System (INIS)

Wang Haofu; Wang Yuwei; Li Jun; Zhao Zonggang; Qi Sen

2010-01-01

Objective: To summarize the clinical experience of perioperative management in performing endovascular abdominal aortic aneurysm repair (EVAR). Methods: EVAR was performed in 22 patients with abdominal aortic aneurysm. The clinical data were retrospectively analyzed. Before treatment the functions of main organs were evaluated and certain measures were adopted in order to protect them. Useful parameters, including the length, diameter, angle and configuration of the proximal and distal aneurysmal neck, the relationship of the aneurysm to aortic branches, the distance from the lowest renal artery to the bifurcation of abdominal aorta, and the quality of access vessels (such as diameter, tortuosity and calcification degree) were determined and assessed with CTA. According to the parameters thus obtained, the suitable stent-graft with ideal diameter and length was selected, and the optimal surgery pattern was employed. Local anesthesia was employed in 20 patients, among them the local anesthesia had to be changed to general anesthesia in one. Epidural anesthesia was carried out in one patient through the surgically-reconstructed iliac artery access,and general anesthesia was employed in one patient who had Stanford type A aortic dissection. The lowest renal artery must be accurately localized before deployment of stent-graft was started. At least one patent internal iliac artery should be reserved when bilateral internal iliac arteries needed to be covered, to be covered by stages or to be reconstructed. After stent-graft placement, angiography must be performed to find out if there was any endoleak and, if any, to determine the type of endoleak and to deal with it properly. Two cases had proximal type I endoleak, so balloon dilation was employed in one and cuff implantation in another one. Distal type I endoleak occurred in one case, but, unfortunately, the iliac artery ruptured when balloon dilation was employed, therefore the patient had to receive vascular repair

Development of the voxel computational phantoms of pediatric patients and their application to organ dose assessment

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Lee, Choonik

A series of realistic voxel computational phantoms of pediatric patients were developed and then used for the radiation risk assessment for various exposure scenarios. The high-resolution computed tomographic images of live patients were utilized for the development of the five voxel phantoms of pediatric patients, 9-month male, 4-year female, 8-year female, 11-year male, and 14-year male. The phantoms were first developed as head and torso phantoms and then extended into whole body phantoms by utilizing computed tomographic images of a healthy adult volunteer. The whole body phantom series was modified to have the same anthropometrics with the most recent reference data reported by the international commission on radiological protection. The phantoms, named as the University of Florida series B, are the first complete set of the pediatric voxel phantoms having reference organ masses and total heights. As part of the dosimetry study, the investigation on skeletal tissue dosimetry methods was performed for better understanding of the radiation dose to the active bone marrow and bone endosteum. All of the currently available methodologies were inter-compared and benchmarked with the paired-image radiation transport model. The dosimetric characteristics of the phantoms were investigated by using Monte Carlo simulation of the broad parallel beams of external phantom in anterior-posterior, posterior-anterior, left lateral, right lateral, rotational, and isotropic angles. Organ dose conversion coefficients were calculated for extensive photon energies and compared with the conventional stylized pediatric phantoms of Oak Ridge National Laboratory. The multi-slice helical computed tomography exams were simulated using Monte Carlo simulation code for various exams protocols, head, chest, abdomen, pelvis, and chest-abdomen-pelvis studies. Results have found realistic estimates of the effective doses for frequently used protocols in pediatric radiology. The results were very

Two-dimensional echocardiographic and RI angiographic features of aneurysm of the ascending aorta in patients with annuloaortic ectasia

International Nuclear Information System (INIS)

Nakamura, Kenji; Suzuki, Shin; Satomi, Gengi

1981-01-01

The purpose of this study was to compare the diagnostic value of two-dimensional echocardiography with that of other methods in the detection and localization of aneurysm involving the ascending aorta in patients with annuloaortic ectasia. Two-dimensional echocardiography, RI angiography, CT scan and aortography were performed in 19 patients (12 patients with Marfan's syndrome, 4 with aortitis syndrome and 3 with postoperative perivalvular aneurysm). Eight of 12 patients with Marfan's syndrome had dissection in the ascending aorta which was confirmed at surgery or autopsy. The following observations were obtained. 1) Dissection of the ascending aorta was clearly demonstrated on the two-dimensional echocardiogram in 7 patients by recording the intinal tear and flap, and in these cases the short axis two-dimensional echocardiogram of the ascending aorta was more useful in identifying the site and extent of dissection. 2) In patients with postoperative perivalvular aneurysms, RI angiography proved to be a more useful and sensitive technique in differentiating a leakage into the aneurysm from clots in the aneurysm. 3) CT scanning proved to be an insensitive technique to detect dissection of the ascending aneurysm and to differentiate a leakage from clots in the perivalvular aneurysm. From these observations, we concluded that two-dimensional echocardiography and RI angiography proved to be sensitive techniques in detecting dissection of the ascending aneurysm and evaluating a postoperative aneurysm in patients with annuloaortic ectasia. (author)

Experimental Study of Flow Through Carotid Aneurysms

Science.gov (United States)

Masoomi, Faezeh; Mejia-Alvarez, Ricardo

2017-11-01

There is evidence that traditional endovascular techniques like coiling are not effective for treatment of wide-neck cerebral aneurysms. Flow Diverter Stents (FDS) have emerged as promising devices for treating complex aneurysms since they enable treatment of aneurysms that were considered untreatable before. Recent studies suggest a number of associated risks with FDS, including in-stent thrombosis, perianeurysmal edema, delayed hemorrhage, and perforator occlusions. Chong et al. simulated hemodynamic behavior using patient-specific data. From their study, it is possible to infer that the standard deviation of energy loss could be a good predictor for intervention success. The aim of this study is to investigate the flow in models of cerebral aneurysms before and after FDS insertion using PIV. These models will be based on actual clinical studies and will be fabricated with advanced additive manufacturing techniques. These data will then be used to explore flow parameters that could inform the likelihood of post-intervention aneurysm rupture, and help determine FDS designs that better suit any particular patient before its procedure.

Subclavian artery aneurysm in a patient with vascular Ehlers-Danlos syndrome.

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Yasuda, Shota; Imoto, Kiyotaka; Uchida, Keiji; Uranaka, Yasuko; Kurosawa, Kenji; Masuda, Munetaka

2016-02-01

We describe our experience of surgical treatment in a 28-year-old woman with vascular Ehlers-Danlos syndrome. A right subclavian artery aneurysm was detected. The right vertebral artery arose from the aneurysm. Digital subtraction angiography showed interruption of the left vertebral artery. The aneurysm was excised and the right vertebral artery was anastomosed end-to-side to the right common carotid artery under deep hypothermia and circulatory arrest. The patient remained very well 4 years after surgery, with no late vascular complication. © The Author(s) 2014.

True aneurysms of the posterior communicating artery: a systematic review and meta-analysis of individual patient data.

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He, Wenzhuan; Gandhi, Chirag D; Quinn, John; Karimi, Reza; Prestigiacomo, Charles J

2011-01-01

To review and analyze systematically the reported cases of "true" posterior communicating artery (PCoA) aneurysm. A retrospective review of the published literature was performed, and a meta-analysis of individual patient data was conducted. Pooled data showed that "true" PCoA aneurysms represent about 1.3% (95% confidence interval [CI] 0.8%, 1.7%) of all intracranial aneurysms and 6.8% (95% CI 4.3%, 9.2%) of all PCoA aneurysms. Mean patient age was 53.5 years (53.5 years ± 15.4), and age range was 23-79 years. Of the 49 patients reported in the literature, 44 (89.8%) were reported as ruptured, and 4 (10.2%) were reported as unruptured. There were no significant differences in ruptured status between age (P = 0.321), left vs right aneurysm (P = 0.537), and shape of aneurysm (P = 0.408). No significant differences in complication rates were found between rupture status (P = 0.27), and operative modalities (P = 0.878). The mean ages of patients who had no complications and patients who had complications were 53 years (53 years ± 2.59) vs 53.2 years (53.2 years ± 5.02) (P = 0.972). "True" PCoA aneurysms represent about 1.3% of all intracranial aneurysms and 6.8% of all PCoA aneurysms. They are more prone to rupture compared with their counterpart junctional aneurysms. When surgical management is indicated, a good understanding of the location and configuration of the aneurysm neck before surgical treatment is critical in the successful treatment of these lesions. Copyright © 2011 Elsevier Inc. All rights reserved.

Hemodynamic Based Coronary Artery Aneurysm Thrombosis Risk Stratification in Kawasaki Disease Patients

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Grande Gutierrez, Noelia; Mathew, M.; McCrindle, B.; Kahn, A.; Burns, J.; Marsden, A.

2017-11-01

Coronary artery aneurysms (CAA) as a result of Kawasaki Disease (KD) put patients at risk for thrombosis and myocardial infarction. Current AHA guidelines recommend CAA diameter >8 mm or Z-score >10 as the criterion for initiating systemic anticoagulation. Our hypothesis is that hemodynamic data derived from computational blood flow simulations is a better predictor of thrombosis than aneurysm diameter alone. Patient-specific coronary models were constructed from CMRI for a cohort of 10 KD patients (5 confirmed thrombosis cases) and simulations with fluid structure interaction were performed using the stabilized finite element Navier-Stokes solver available in SimVascular. We used a closed-loop lumped parameter network (LPN) to model the heart and vascular boundary conditions coupled numerically to the flow solver. An automated parameter estimation method was used to match LPN values to clinical data for each patient. Hemodynamic data analysis resulted in low correlation between Wall Shear Stress (WSS)/ Particle Residence Time (PRT) and CAA diameter but demonstrates the positive correlation between hemodynamics and adverse patient outcomes. Our results suggest that quantifying WSS and PRT should enable identification of regions at higher risk of thrombosis. We propose a quantitative method to non-invasively assess the abnormal flow in CAA following KD that could potentially improve clinical decision-making regarding anticoagulation therapy.

Two-dimensional echocardiographic and RI angiographic features of aneurysm of the ascending aorta in patients with annuloaortic ectasia

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Nakamura, K.; Suzuki, S.; Satomi, G. (Tokyo Women' s Medical Coll. (Japan). Heart Inst. and Hospital)

1981-03-01

The purpose of this study was to compare the diagnostic value of two-dimensional echocardiography with that of other methods in the detection and localization of aneurysm involving the ascending aorta in patients with annuloaortic ectasia. Two-dimensional echocardiography, RI angiography, CT scan and aortography were performed in 19 patients (12 patients with Marfan's syndrome, 4 with aortitis syndrome and 3 with postoperative perivalvular aneurysm). Eight of 12 patients with Marfan's syndrome had dissection in the ascending aorta which was confirmed at surgery or autopsy. The following observations were obtained. 1) Dissection of the ascending aorta was clearly demonstrated on the two-dimensional echocardiogram in 7 patients by recording the intinal tear and flap, and in these cases the short axis two-dimensional echocardiogram of the ascending aorta was more useful in identifying the site and extent of dissection. 2) In patients with postoperative perivalvular aneurysms, RI angiography proved to be a more useful and sensitive technique in differentiating a leakage into the aneurysm from clots in the aneurysm. 3) CT scanning proved to be an insensitive technique to detect dissection of the ascending aneurysm and to differentiate a leakage from clots in the perivalvular aneurysm. From these observations, we concluded that two-dimensional echocardiography and RI angiography proved to be sensitive techniques in detecting dissection of the ascending aneurysm and evaluating a postoperative aneurysm in patients with annuloaortic ectasia.

De novo giant A2 aneurysm following anterior communicating artery occlusion.

Science.gov (United States)

Ibrahim, Tarik F; Hafez, Ahmad; Andrade-Barazarte, Hugo; Raj, Rahul; Niemela, Mika; Lehto, Hanna; Numminen, Jussi; Jarvelainen, Juha; Hernesniemi, Juha

2015-01-01

De novo intracranial aneurysms are reported to occur with varying incidence after intracranial aneurysm treatment. They are purported to be observed, however, with increased incidence after Hunterian ligation; particularly in cases of carotid artery occlusion for giant or complex aneurysms deemed unclippable. We report a case of right-sided de novo giant A2 aneurysm 6 years after an anterior communicating artery (ACoA) aneurysm clipping. We believe this de novo aneurysm developed in part due to patient-specific risk factors but also a significant change in cerebral hemodynamics. The ACoA became occluded after surgery that likely altered the cerebral hemodynamics and contributed to the de novo aneurysm. We believe this to be the first reported case of a giant de novo aneurysm in this location. Following parent vessel occlusion (mostly of the carotid artery), there are no reports of any de novo aneurysms in the pericallosal arteries let alone a giant one. The patient had a dominant right A1 and the sudden increase in A2 blood flow likely resulted in increased wall shear stress, particularly in the medial wall of the A2 where the aneurysm occurred 2 mm distal to the A1-2 junction. ACoA preservation is a key element of aneurysm surgery in this location. Suspected occlusion of this vessel may warrant closer radiographic follow-up in patients with other risk factors for aneurysm development.

Aneurysmal subarachnoid hemorrhage: outcome of aneurysm clipping versus coiling in anterior circulation aneurysm

International Nuclear Information System (INIS)

Wadd, I.H.; Haroon, A.; Ansari, S.

2015-01-01

To compare the neurological outcome of microsurgical clipping versus coiling in patients with anterior circulation aneurysm. Study Design: Comparative study. Place and Duration of Study: Department of Neurosurgery, Lahore General Hospital, Lahore, from January 2010 to December 2013. Methodology: Patients aged 14 - 60 years, with ruptured cerebral aneurysm of anterior circulation and World Federation of Neurosurgical Society (WFNS) grades 1, 2 and 3 were included. Patients more than 60 years, medically unfit patient and posterior circulation aneurysms and WFNS grades 4 and 5 were excluded. Aneurysm sac obliteration was done in randomized manner with microsurgical clipping or coiling. Postoperatively, the patients were assessed and followed-up upto one year for outcome parameters on the bases of WFNS grade and Modified Ranking Scale (mRS) as favourable (mRS =2 ) and unfavourable (mRS > 2). Results: Among 140 subjects selected for study, 70 were included in group A, i.e. coiling and other 70 were in group B, i.e. clipping. The median age of patients in group A was 52.5 ± 10 years and in group B was 51.00 ± years. Overall, 56 (40%) males, 28 (60%) males in each group; and 84 (60%) females, 42 (60%) in each group were included. The male to female ratio in this study was 1:1.5. In group A, i.e. coiling, 27 (38.6%) patients had no disability (grades 1 and 2), 25 (35.7%) were slightly disabled (grade 3) and 18 (25.7%) had moderate disability (grade 4); whereas in group B, i.e. clipping group 23 (32.9%) patients had no disability (grades 1 and 2), 23 (32.9%) were slightly disabled (grade 3) and 24 (34.3%) had moderate disability (grade 4). At one year follow-up, in group A, favourable outcome was achieved in 56 (80%) of patients compared to 48 (68.6%) in group B; whilst, 14 (20%) patients in group A and 22 (33.1%) in group B showed unfavourable outcome. Although mortality rate was higher in clipping (n=3, 4.3%) as compared to coiling (n=1, 1.4%), but was not statistically

Perioperative nursing for patients receiving endovascular therapy for ruptured abdominal aortic aneurysm

International Nuclear Information System (INIS)

Dong Yanfen; Pan Wei; Zhang Hongpeng; Guo Wei; Liu Xiaoping; Wei Ren

2010-01-01

Objective: To discuss the nursing strategy and practical measures for patients with ruptured abdominal aortic aneurysm during the perioperative period of endovascular intervention. Methods: Endovascular therapy was carried out in 34 patients with ruptured abdominal aortic aneurysm,who were encountered in our department during the period of July 1997 to September 2008. The clinical data were retrospectively analyzed and the nursing points were summarized. Results: The average hospitalization days of the 34 patients were (14 ± 5) days, the mortality rate within 30 days was 23.5% (8/34). No nursing-related complications occurred. Conclusion: A comprehensive understanding of the mechanism, development and clinical evolution of ruptured abdominal aortic aneurysm is very important for nursing care. For nursing staff, well mastering the relevant nursing technique, carefully guarding against any nursing errors and lessening patient's suffering as far as possible, all these are the task of primary importance. (authors)

Specific developed phantoms and software to assess radiological equipment image quality

International Nuclear Information System (INIS)

Verdu, G.; Rodenas, F.

2011-01-01

The use of radiographic phantoms specifically designed to evaluate the operation of the radiographic equipment lets the study of the image quality obtained by this equipment in an objective way. In digital radiographic equipment, the analysis of the image quality can be automatized because the acquisition of the image is possible in different technologies that are, computerized radiography or phosphor plate and direct radiography or detector. In this work we have shown an application to assess automatically the constancy quality image in the image chain of the radiographic equipment. This application is integrated by designed radiographic phantoms which are adapted to conventional, dental equipment and specific developed software for the automatic evaluation of the phantom image quality. The software is based on digital image processing techniques that let the automatic detection of the different phantom tests by edge detector, morphological operators, threshold histogram techniques, etc. The utility developed is enough sensitive to the radiographic equipment of operating conditions of voltage (kV) and charge (mAs). It is a friendly user programme connected with a data base of the hospital or clinic where it has been used. After the phantom image processing the user can obtain an inform with a resume of the imaging system state with accepting and constancy results. (author)

Specific developed phantoms and software to assess radiological equipment image quality

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Verdu, G., E-mail: gverdu@iqn.upv.es [Universidad Politecnica de Valencia (Spain). Dept. de Ingenieria Quimica y Nuclear; Mayo, P., E-mail: p.mayo@titaniast.com [TITANIA Servicios Teconologicos, Valencia (Spain); Rodenas, F., E-mail: frodenas@mat.upv.es [Universidad Politecnica de Valencia (Spain). Dept. de Matematica Aplicada; Campayo, J.M., E-mail: j.campayo@lainsa.com [Logistica y Acondicionamientos Industriales S.A.U (LAINSA), Valencia (Spain)

2011-07-01

The use of radiographic phantoms specifically designed to evaluate the operation of the radiographic equipment lets the study of the image quality obtained by this equipment in an objective way. In digital radiographic equipment, the analysis of the image quality can be automatized because the acquisition of the image is possible in different technologies that are, computerized radiography or phosphor plate and direct radiography or detector. In this work we have shown an application to assess automatically the constancy quality image in the image chain of the radiographic equipment. This application is integrated by designed radiographic phantoms which are adapted to conventional, dental equipment and specific developed software for the automatic evaluation of the phantom image quality. The software is based on digital image processing techniques that let the automatic detection of the different phantom tests by edge detector, morphological operators, threshold histogram techniques, etc. The utility developed is enough sensitive to the radiographic equipment of operating conditions of voltage (kV) and charge (mAs). It is a friendly user programme connected with a data base of the hospital or clinic where it has been used. After the phantom image processing the user can obtain an inform with a resume of the imaging system state with accepting and constancy results. (author)

The effects of preoperative cardiology consultation prior to elective abdominal aortic aneurysm repair on patient morbidity.

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Boniakowski, Anna E; Davis, Frank M; Phillips, Amanda R; Robinson, Adina B; Coleman, Dawn M; Henke, Peter K

2017-08-01

Objectives The relationship between preoperative medical consultations and postoperative complications has not been extensively studied. Thus, we investigated the impact of preoperative consultation on postoperative morbidity following elective abdominal aortic aneurysm repair. Methods A retrospective review was conducted on 469 patients (mean age 72 years, 20% female) who underwent elective abdominal aortic aneurysm repair from June 2007 to July 2014. Data elements included detailed medical history, preoperative cardiology consultation, and postoperative complications. Primary outcomes included 30-day morbidity, consult-specific morbidity, and mortality. A bivariate probit regression model accounting for the endogeneity of binary preoperative medical consult and patient variability was estimated with a maximum likelihood function. Results Eighty patients had preoperative medical consults (85% cardiology); thus, our analysis focuses on the effect of cardiac-related preoperative consults. Hyperlipidemia, increased aneurysm size, and increased revised cardiac risk index increased likelihood of referral to cardiology preoperatively. Surgery type (endovascular versus open repair) was not significant in development of postoperative complications when controlling for revised cardiac risk index ( p = 0.295). After controlling for patient comorbidities, there was no difference in postoperative cardiac-related complications between patients who did and did not undergo cardiology consultation preoperatively ( p = 0.386). Conclusions When controlling for patient disease severity using revised cardiac risk index risk stratification, preoperative cardiology consultation is not associated with postoperative cardiac morbidity.

Endovascular treatment for pediatric intracranial aneurysms

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Lv, Xianli; Jiang, Chuhan; Li, Youxiang; Yang, Xinjian; Wu, Zhongxue [Capital Medical University, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Beijing, Hebei (China)

2009-11-15

The purpose of this study is to report the characteristics and outcomes of pediatric patients with intracranial aneurysms. From 1998 to 2005, 25 pediatric patients (aged {<=}17 years) with intracranial aneurysm were treated at our institute. Eleven of 25 patients had subarachnoid hemorrhage. In ten patients, the aneurysm was an incidental finding. One patient presented with cranial nerves dysfunction and three with neurological deficits. The locations of the aneurysms were as follows: vertebral artery (VA; n = 9), middle cerebral artery (MCA; n = 5), posterior cerebral artery (PCA; n = 4), basilar artery (BA; n = 2), anterior communicating artery (n = 2), anterior cerebral artery (n = 2), and internal carotid artery (n = 1). Five patients were treated with selective embolization with coils. Sixteen patients were treated with parent vessel occlusion (PVO). Eight PVOs were performed with balloons and eight were performed with coils. One patient with a VA aneurysm was spontaneously thrombosed 4 days after the initial diagnostic angiogram. In three patients treated with stent alone or stent-assisted coiling, one with BA trunk aneurysm died. One aneurismal recurrence occurred and was retreated. At a mean follow-up duration of 23.5 months, 96% of patients had a Glasgow Outcome Scale score of 4 or 5. Pediatric intracranial aneurysms occur more commonly in male patients and have a predilection for the VA, PCA, and MCA. PVO is an effective and safe treatment for fusiform aneurysms. Basilar trunk fusiform aneurysms were difficult to treat and were associated with a high mortality rate. (orig.)

Bifurcations sights, sounds, and mathematics

CERN Document Server

Matsumoto, Takashi; Kokubu, Hiroshi; Tokunaga, Ryuji

1993-01-01

Bifurcation originally meant "splitting into two parts. " Namely, a system under­ goes a bifurcation when there is a qualitative change in the behavior of the sys­ tem. Bifurcation in the context of dynamical systems, where the time evolution of systems are involved, has been the subject of research for many scientists and engineers for the past hundred years simply because bifurcations are interesting. A very good way of understanding bifurcations would be to see them first and study theories second. Another way would be to first comprehend the basic concepts and theories and then see what they look like. In any event, it is best to both observe experiments and understand the theories of bifurcations. This book attempts to provide a general audience with both avenues toward understanding bifurcations. Specifically, (1) A variety of concrete experimental results obtained from electronic circuits are given in Chapter 1. All the circuits are very simple, which is crucial in any experiment. The circuits, howev...

Transcatheter Coil Embolization of Splenic Artery Aneurysm

International Nuclear Information System (INIS)

Yamamoto, Satoshi; Hirota, Shozo; Maeda, Hiroaki; Achiwa, Sachiko; Arai, Keisuke; Kobayashi, Kaoru; Nakao, Norio

2008-01-01

The purpose of this study was to evaluate clinical results and technical problems of transcatheter coil embolization for splenic artery aneurysm. Subjects were 16 patients (8 men, 8 women; age range, 40-80 years) who underwent transcatheter embolization for splenic artery aneurysm (14 true aneurysms, 2 false aneurysms) at one of our hospitals during the period January 1997 through July 2005. Two aneurysms (12.5%) were diagnosed at the time of rupture. Multiple splenic aneurysms were found in seven patients. Aneurysms were classified by site as proximal (or strictly ostial) (n = 3), middle (n = 3), or hilar (n = 10). The indication for transcatheter arterial embolization was a false or true aneurysm 20 mm in diameter. Embolic materials were fibered coils and interlocking detachable coils. Embolization was performed by the isolation technique, the packing technique, or both. Technically, all aneurysms were devascularized without severe complications. Embolized aneurysms were 6-40 mm in diameter (mean, 25 mm). Overall, the primary technical success rate was 88% (14 of 16 patients). In the remaining 2 patients (12.5%), partial recanalization occurred, and re-embolization was performed. The secondary technical success rate was 100%. Seven (44%) of the 16 study patients suffered partial splenic infarction. Intrasplenic branching originating from the aneurysm was observed in five patients. We conclude that transcatheter coil embolization should be the initial treatment of choice for splenic artery aneurysm

Abdominal aortic aneurysms: virtual imaging and analysis through a remote web server

International Nuclear Information System (INIS)

Neri, Emanuele; Bargellini, Irene; Vignali, Claudio; Bartolozzi, Carlo; Rieger, Michael; Jaschke, Werner; Giachetti, Andrea; Tuveri, Massimiliano

2005-01-01

The study describes the application of a web-based software in the planning of the endovascular treatment of abdominal aortic aneurysms (AAA). The software has been developed in the framework of a 2-year research project called Aneurysm QUAntification Through an Internet Collaborative System (AQUATICS); it allows to manage remotely Virtual Reality Modeling Language (VRML) models of the abdominal aorta, derived from multirow computed tomography angiography (CTA) data sets, and to obtain measurements of diameters, angles and centerline lengths. To test the reliability of measurements, two radiologists performed a detailed analysis of multiple 3D models generated from a synthetic phantom, mimicking an AAA. The system was tested on 30 patients with AAA; CTA data sets were mailed and the time required for segmentation and measurement were collected for each case. The Bland-Altman plot analysis showed that the mean intra- and inter-observer differences in measures on phantoms were clinically acceptable. The mean time required for segmentation was 1 h (range 45-120 min). The mean time required for measurements on the web was 7 min (range 4-11 min). The AQUATICS web server may provide a rapid, standardized and accurate tool for the evaluation of AAA prior to the endovascular treatment. (orig.)

Primary extracranial vertebral artery aneurysms.

Science.gov (United States)

Morasch, Mark D; Phade, Sachin V; Naughton, Peter; Garcia-Toca, Manuel; Escobar, Guillermo; Berguer, Ramon

2013-05-01

Extracranial vertebral artery aneurysms are uncommon and are usually associated with trauma or dissection. Primary cervical vertebral aneurysms are even rarer and are not well described. The presentation and natural history are unknown and operative management can be difficult. Accessing aneurysms at the skull base can be difficult and, because the frail arteries are often afflicted with connective tissue abnormalities, direct repair can be particularly challenging. We describe the presentation and surgical management of patients with primary extracranial vertebral artery aneurysms. In this study we performed a retrospective, multi-institutional review of patients with primary aneurysms within the extracranial vertebral artery. Between January 2000 and January 2011, 7 patients, aged 12-56 years, were noted to have 9 primary extracranial vertebral artery aneurysms. All had underlying connective tissue or another hereditary disorder, including Ehler-Danlos syndrome (n=3), Marfan's disease (n=2), neurofibromatosis (n=1), and an unspecified connective tissue abnormality (n=1). Eight of 9 aneurysms were managed operatively, including an attempted bypass that ultimately required vertebral ligation; the contralateral aneurysm on this patient has not been treated. Open interventions included vertebral bypass with vein, external carotid autograft, and vertebral transposition to the internal carotid artery. Special techniques were used for handling the anastomoses in patients with Ehler-Danlos syndrome. Although endovascular exclusion was not performed in isolation, 2 hybrid procedures were performed. There were no instances of perioperative stroke or death. Primary extracranial vertebral artery aneurysms are rare and occur in patients with hereditary disorders. Operative intervention is warranted in symptomatic patients. Exclusion and reconstruction may be performed with open and hybrid techniques with low morbidity and mortality. Copyright © 2013 Elsevier Inc. All rights

Clinical outcomes of surgical clipping for intracranial aneurysms in patients with a Hunt and Hess grade 4 or 5

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Yang Zhang

2016-06-01

Full Text Available ABSTRACT We retrospectively evaluated the records of 49 grade 4 and 5 patients with 42 intracranial aneurysms treated within 72 h of subarachnoid hemorrhage (SAH. In total, 35 patients (71% were grade 4, and 14 (29% were grade 5. A total of 42 (85% patients had one aneurysm, 6 (12% had two aneurysms, and 1 (3% had three aneurysms. Out of 49 patients, one technical (2% and one clinical (2% complication occurred at surgery. Twenty-one (43% patients recovered well, including 7 with postoperative hematoma requiring an immediate evacuation of a clot. Fourteen (29% patients had hydrocephalus and required a ventriculo-peritoneal shunt; 12 patients underwent tracheotomy postoperatively due to coma and pulmonary infection. We found that patients with Hunt and Hess grade 4 and 5 aneurysms can undergo successful neurosurgical clipping of the aneurysms after SAH. However, the morbidity and mortality rates remain high because of their poor clinical condition and a high incidence of vasospasm during treatment.

Risk factors and outcome in 100 patients with aneurysmal subarachnoid hemorrhage

Directory of Open Access Journals (Sweden)

Bonilha Leonardo

2001-01-01

Full Text Available OBJECTIVE: Clinical and surgical outcome of patients with subarachnoid hemorrhage (SAH due to ruptured aneurysm were assessed in comparison to pre-operative data and risk factors such as previous medical history, clinical presenting condition, CT findings and site of bleeding. METHODS: We evaluated 100 consecutive patients with aneurysmal SAH. Gender, color, history of hypertension, smoking habit, site and size of aneurysm, admittance and before surgery Hunt Hess scale, need for cerebro-spinal fluid shunt, presence of complications during the surgical procedure, Glasgow Outcome Scale, presence of vasospasm and of rebleeding were assessed and these data matched to outcome. For statistical analysis, we applied the chi-squared test or Fisher's test using the pondered kappa coeficient. Kruskal-Wallis test was used for comparison of continue variables. Tendency of proportion was analyzed through Cochran-Armitage test. Significance level adopted was 5%. RESULTS: Patients studied were mainly white, female, without previous history of hypertension and non-smokers. Upon hospital admittance, grade 2 of Hunt-Hess scale was most frequently observed (34%, while grade 3 of Fisher scale was the most prevalent. Single aneurysms were most frequent at anterior circulation, between 12 and 24 mm. The most frequent Glasgow Outcome Scale observed was 5 (60%. Hunt Hess upon the moment of surgery and presence of complications during surgical procedure showed positive correlation with clinical outcome (p=0.00002 and p=0.001, respectively. Other variables were not significantly correlated to prognosis. Tendency of proportion was observed between Hunt-Hess scale and Fisher scale. CONCLUSION: Among variables such as epidemiological data, previous medical history and presenting conditions of patients with ruptured aneurysms, the Hunt-Hess scale upon the moment of surgery and the presence of surgical adversities are statistically related to degree of disability.

The influence of atmospheric pressure on aortic aneurysm rupture--is the diameter of the aneurysm important?

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Urbanek, Tomasz; Juśko, Maciej; Niewiem, Alfred; Kuczmik, Wacław; Ziaja, Damian; Ziaja, Krzysztof

2015-01-01

The rate of aortic aneurysm rupture correlates with the aneurysm's diameter, and a higher rate of rupture is observed in patients with larger aneurysms. According to the literature, contradictory results concerning the relationship between atmospheric pressure and aneurysm size have been reported. In this paper, we assessed the influence of changes in atmospheric pressure on abdominal aneurysm ruptures in relationship to the aneurysm's size. The records of 223 patients with ruptured abdominal aneurysms were evaluated. All of the patients had been admitted to the department in the period 1997-2007 from the Silesia region. The atmospheric pressures on the day of the rupture and on the days both before the rupture and between the rupture events were compared. The size of the aneurysm was also considered in the analysis. There were no statistically significant differences in pressure between the days of rupture and the remainder of the days within an analysed period. The highest frequency of the admission of patients with a ruptured aortic aneurysm was observed during periods of winter and spring, when the highest mean values of atmospheric pressure were observed; however, this observation was not statistically confirmed. A statistically non-significant trend towards the higher rupture of large aneurysms (> 7 cm) was observed in the cases where the pressure increased between the day before the rupture and the day of the rupture. This trend was particularly pronounced in patients suffering from hypertension (p = 0.1). The results of this study do not support the hypothesis that there is a direct link between atmospheric pressure values and abdominal aortic aneurysm ruptures.

Repair of left coronary artery aneurysm, recurrent ascending aortic aneurysm, and mitral valve prolapse 19 years after Bentall's procedure in a patient with Marfan syndrome.

Science.gov (United States)

Badmanaban, Balaji; Mallon, Peter; Campbell, Norman; Sarsam, Mazin A I

2004-01-01

A 45-year-old female with Marfan syndrome had a Bentall's procedure performed 19 years ago. She presented with a 4-year history of gradually worsening dyspnea and decreasing exercise tolerance. Investigations revealed severe mitral valve prolapse, a left main stem coronary artery (LMSCA) aneurysm, and a recurrent aneurysm of the ascending aorta. The mitral valve was replaced and the aortic aneurysmal sac and the LMSCA aneurysm were then repaired by a modified Bentall procedure. The patient made an uneventful recovery and was discharged home.

Perigraft Plug Embolization of the Internal Iliac Artery and Implantation of a Bifurcated Stentgraft: One Treatment Option for Insufficient Tubular Stentgraft Repair of a Common Iliac Artery Aneurysm

Energy Technology Data Exchange (ETDEWEB)

Goltz, Jan Peter, E-mail: janpeter.goltz@uksh.de; Loesaus, Julia; Frydrychowicz, Alex; Barkhausen, Jörg [University Hospital of Schleswig-Holstein, Department for Radiology and Nuclear Medicine (Germany); Wiedner, Marcus [University Hospital of Schleswig-Holstein, Clinic for Surgery (Germany)

2016-02-15

We report an endovascular technique for the treatment of type Ia endoleak after a plain tubular stentgraft had been implanted for a large common iliac artery aneurysm with an insufficient proximal landing zone and without occlusion of the hypogastric in another hospital. CT follow-up showed an endoleak with continuous sac expansion over 12 months. This was classified as type Ia by means of dynamic contrast-enhanced MRI. Before a bifurcated stentgraft was implanted to relocate the landing zone more proximally, the still perfused ipsilateral hypogastric artery was embolized to prevent a type II endoleak. A guidewire was manipulated alongside the indwelling stentgraft. The internal iliac artery could then be selectively intubated followed by successful plug embolization of the vessel’s orifice despite the stentgraft being in place.

Individualized adjustments to reference phantom internal organ dosimetry—scaling factors given knowledge of patient internal anatomy

Science.gov (United States)

Wayson, Michael B.; Bolch, Wesley E.

2018-04-01

Various computational tools are currently available that facilitate patient organ dosimetry in diagnostic nuclear medicine, yet they are typically restricted to reporting organ doses to ICRP-defined reference phantoms. The present study, while remaining computational phantom based, provides straightforward tools to adjust reference phantom organ dose for both internal photon and electron sources. A wide variety of monoenergetic specific absorbed fractions were computed using radiation transport simulations for tissue spheres of varying size and separation distance. Scaling methods were then constructed for both photon and electron self-dose and cross-dose, with data validation provided from patient-specific voxel phantom simulations, as well as via comparison to the scaling methodology given in MIRD Pamphlet No. 11. Photon and electron self-dose was found to be dependent on both radiation energy and sphere size. Photon cross-dose was found to be mostly independent of sphere size. Electron cross-dose was found to be dependent on sphere size when the spheres were in close proximity, owing to differences in electron range. The validation studies showed that this dataset was more effective than the MIRD 11 method at predicting patient-specific photon doses for at both high and low energies, but gave similar results at photon energies between 100 keV and 1 MeV. The MIRD 11 method for electron self-dose scaling was accurate for lower energies but began to break down at higher energies. The photon cross-dose scaling methodology developed in this study showed gains in accuracy of up to 9% for actual patient studies, and the electron cross-dose scaling methodology showed gains in accuracy up to 9% as well when only the bremsstrahlung component of the cross-dose was scaled. These dose scaling methods are readily available for incorporation into internal dosimetry software for diagnostic phantom-based organ dosimetry.

Dutch experience with the fenestrated Anaconda endograft for short-neck infrarenal and juxtarenal abdominal aortic aneurysm repair.

Science.gov (United States)

Dijkstra, Martijn L; Tielliu, Ignace F J; Meerwaldt, Robbert; Pierie, Maurice; van Brussel, Jerome; Schurink, Geert Willem H; Lardenoye, Jan-Willem; Zeebregts, Clark J

2014-08-01

In the past decennium, the management of short-neck infrarenal and juxtarenal aortic aneurysms with fenestrated endovascular aneurysm repair (FEVAR) has been shown to be successful, with good early and midterm results. Recently, a new fenestrated device, the fenestrated Anaconda (Vascutek, Renfrewshire, Scotland), was introduced. The aim of this study was to present the current Dutch experience with this device. A prospectively held database of patients treated with the fenestrated Anaconda endograft was analyzed. Decision to treat was based on current international guidelines. Indications for FEVAR included an abdominal aortic aneurysm (AAA) with unsuitable neck anatomy for EVAR. Planning was performed on computed tomography angiography images using a three-dimensional workstation. Between May 2011 and September 2013, 25 patients were treated in eight institutions for juxtarenal (n = 23) and short-neck AAA (n = 2). Median AAA size was 61 mm (59-68.5 mm). All procedures except one were performed with bifurcated devices. A total of 56 fenestrations were incorporated, and 53 (94.6%) were successfully cannulated and stented. One patient died of bowel ischemia caused by occlusion of the superior mesenteric artery. On completion angiography, three type I endoleaks and seven type II endoleaks were observed. At 1 month of follow-up, all endoleaks had spontaneously resolved. Median follow-up was 11 months (range, 1-29 months). There were no aneurysm ruptures or aneurysm-related deaths and no reinterventions to date. Primary patency at 1 month of cannulated and stented target vessels was 96%. Initial and short-term results of FEVAR using the fenestrated Anaconda endograft are promising, with acceptable technical success and short-term complication rates. Growing experience and long-term results are needed to support these findings. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Vortex dynamics in ruptured and unruptured intracranial aneurysms

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Trylesinski, Gabriel

Intracranial aneurysms (IAs) are a potentially devastating pathological dilation of brain arteries that affect 1.5-5 % of the population. Causing around 500 000 deaths per year worldwide, their detection and treatment to prevent rupture is critical. Multiple recent studies have tried to find a hemodynamics predictor of aneurysm rupture, but concluded with distinct opposite trends using Wall Shear Stress (WSS) based parameters in different clinical datasets. Nevertheless, several research groups tend to converge for now on the fact that the flow patterns and flow dynamics of the ruptured aneurysms are complex and unstable. Following this idea, we investigated the vortex properties of both unruptured and ruptured cerebral aneurysms. A brief comparison of two Eulerian vortex visualization methods (Q-criterion and lambda 2 method) showed that these approaches gave similar results in our complex aneurysm geometries. We were then able to apply either one of them to a large dataset of 74 patient specific cases of intracranial aneurysms. Those real cases were obtained by 3D angiography, numerical reconstruction of the geometry, and then pulsatile CFD simulation before post-processing with the mentioned vortex visualization tools. First we tested the two Eulerian methods on a few cases to verify their implementation we made as well as compare them with each other. After that, the Q-criterion was selected as method of choice for its more obvious physical meaning (it shows the balance between two characteristics of the flow, its swirling and deformation). Using iso-surfaces of Q, we started by categorizing the patient-specific aneurysms based on the gross topology of the aneurysmal vortices. This approach being unfruitful, we found a new vortex-based characteristic property of ruptured aneurysms to stratify the rupture risk of IAs that we called the Wall-Kissing Vortices, or WKV. We observed that most ruptured aneurysms had a large amount of WKV, which appears to agree with

Postoperative subdural hygroma and chronic subdural hematoma after unruptured aneurysm surgery: age, sex, and aneurysm location as independent risk factors.

Science.gov (United States)

Park, Jaechan; Cho, Jae-Hoon; Goh, Duck-Ho; Kang, Dong-Hun; Shin, Im Hee; Hamm, In-Suk

2016-02-01

This study investigated the incidence and risk factors for the postoperative occurrence of subdural complications, such as a subdural hygroma and resultant chronic subdural hematoma (CSDH), following surgical clipping of an unruptured aneurysm. The critical age affecting such occurrences and follow-up results were also examined. The case series included 364 consecutive patients who underwent aneurysm clipping via a pterional or superciliary keyhole approach for an unruptured saccular aneurysm in the anterior cerebral circulation between 2007 and 2013. The subdural hygromas were identified based on CT scans 6-9 weeks after surgery, and the volumes were measured using volumetry studies. Until their complete resolution, all the subdural hygromas were followed using CT scans every 1-2 months. Meanwhile, the CSDHs were classified as nonoperative or operative lesions that were treated by bur-hole drainage. The age and sex of the patients, aneurysm location, history of a subarachnoid hemorrhage (SAH), and surgical approach (pterional vs superciliary) were all analyzed regarding the postoperative occurrence of a subdural hygroma or CSDH. The follow-up results of the subdural complications were also investigated. Seventy patients (19.2%) developed a subdural hygroma or CSDH. The results of a multivariate analysis showed that advanced age (p = 0.003), male sex (p 60 years, which achieved a 70% sensitivity and 69% specificity with regard to predicting such subdural complications. The female patients ≤ 60 years of age showed a negligible incidence of subdural complications for all aneurysm groups, whereas the male patients > 60 years of age showed the highest incidence of subdural complications at 50%-100%, according to the aneurysm location. The subdural hygromas detected 6-9 weeks postoperatively showed different follow-up results, according to the severity. The subdural hygromas that converted to a CSDH were larger in volume than the subdural hygromas that resolved

Presence of anatomical variations of the circle of Willis in patients undergoing surgical treatment for ruptured intracranial aneurysms

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Stojanović Nebojša

2009-01-01

Full Text Available Background/Aim. The presence of aneurysmal changes on the brain blood vessels has been subject to numerous research. This study investigated the relation between ruptured aneurysms and anatomical configuration of the Circle of Willis, with the purpose to obtain an insight into their mutual connection. Methods. The analysis included 114 patients suffering from ruptured intracranial aneurysms. Preoperative cerebral angiography was performed and compared with the intraoperative findings in order to attain a precise insight into morphological changes occurring on the circle of Willis. Results. The prevalence of asymmetrical Willis in the whole group of patients was 64%. Within the group of patients suffering from multiple aneurysms, the presence of asymmetrical Willis' circle was 75.7%. The highest incidence of the asymmetrical Circle of Willis was found among patients with aneurysmal rupture detected at the anterior comunicative artery (ACoA site (72.7% among cases with solitary and 100% among those with multiple aneurysms. Morphological changes on the A1 segment of ACoA were observed in 50 (44% cases, with higher incidence found on the right side (60%. When comparing location of ruptured aneurysms between genders, a statistically significant prevalence of the ruptured aneurisms on ACoA was present in men, whereas women showed higher incidence of ruptured aneurysms on interior cartid artery (ICA site (p < 0.01. The linkage between aneurysms with hypoplasia of the A1 segment of ACA and decreasing of the angle at which segments A1 and A2 join suggests the relationship between their onset, corresponding configuration type of Willis and subsequent hemodynamic changes. Conclusion. High incidence of asymmetry of Willis circle in the group of patients with ruptured aneurysms imply association of asymmetrical configuration and disorder in haemodynamic relations with forming and rupture of intracranial aneurysms.

Bleeding aneurysms of the celiac trunk

International Nuclear Information System (INIS)

Ziviello, M.; D'Isa, L.; Siani, A.; Maglione, F.; Cataldo, B.; Ziviello, R.; Capalbogiliberti, R.

1988-01-01

The authors report their experience in the study of bleeding aneurysms of the celiac arteries. Eleven patients were examined with US,CT, and angiography (8 hepatic artery aneurysms and 3 splenic artery aneurysms). Clinical findings included digestive bleeding, upper abdominal pain, palpable pulsating masses, and jaundice. Patient history included blunt abdominal trauma, penetrating trauma due to gunshot, acute pancreatitis, recent hepatic biospy. In all cases US showed an abdominal mass ranging in size from 2 to 10 cm. US findings included cyst-like lesions (8 cases), anobulated solid-like lesion, and complex lesion (2 cases). Continuity of the lesion with adjancent arterial vessels was noted in 5/11 cases, and pulsing activity in 3/11 cases. US patterns, although not specific, play an important role in the diagnosis when associated to other elements such as arterial continuity, mass pulsatility, patient history, and gastrointestinal bleeding. They suggest the need for more specific imaging exams, i.e. CT and angiography, and help avoid dangerous diagnostic biopsies. CT was performed to confirm US findings in 5 cases, and detected either hypodense cystic masses, or inhomogeneous masses with arterial enhancement after bolus injection of cm. CT was used to better demonstrate the lumen, patency of the vessel, the walls of the vessel, and the parietal thrombotic component. The typical arterial enhancement was the decisive finding for the diagnosis, even though a total continuity with arterial vessels was never observed. Angiography was the method of choice for the preoperative demonstration of hepatic artery aneurysms (10 cases) and for occlusive treatment with Gianturco coils (3 cases)

Differentiating aneurysm from infundibular dilatation by volume rendering MRA. Techniques for improving depiction of the posterior communicating and anterior choroidal arteries

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Kato, Takaaki; Ito, Takeo; Hasunuma, Masahiro; Sakamoto, Yasuo; Kohama, Ikuhide; Yonemori, Terutake; Izumo, Masaki [Hakodate Shintoshi Hospital, Hokkaido (Japan)

2002-12-01

With the spread of brain dock procedures, non-invasive magnetic resonance angiography (MRA) is being utilized to broadly screen for brain blood vessel diseases. However, diagnosis of cerebral aneurysm can be difficult by routine MRA. In particular, differentiating aneurysms and infundibular dilatations (IDS) of the posterior communicating artery (PCoA) and anterior choroidal artery (AChA) at their bifurcations with the internal carotid artery (ICA) is extremely difficult and additional studies are frequently necessary. In this situation, three-dimensional computed tomography angiography (3D-CTA) and cerebral angiography have been utilized, but both techniques are invasive. Furthermore, images from cerebral angiography are only two-dimensional, and 3D-CTA requires differentiation between aneurysm and ID by observing configurational changes at the apex of the protrusion and by following gradual changes to the threshold. We therefore undertook the following steps to improve both depiction of the PCoA and AChA and differential diagnosis between aneurysm and ID: reduced slice thickness and increased number of excitations; utilized volume rendering methods to construct images; lowered thresholds for the beginning of the PCoA and AChA arteries, which represent the regions of interest. In all 11 cases that we operated on, cerebral aneurysms were diagnosed correctly and the minimum neck diameter of the cerebral aneurysm was 1.2 mm. In addition, the number of AChAs and PCoAs present in target MRA and in operational views were evaluated. In one case with an AChA aneurysm, a PCoA was not detected by target MRA, because the ICA deviated posterolaterally and pushed the PCoA to the posterior clinoid process, and blood flow was poor in operational views. In another 2 cases with AChA aneurysms, only one AChA was described in target MRA, whereas two aneurysms were present. However, one of these had a diameter less than 1 mm. In conclusion, this method offers an extremely useful aid

Differentiating aneurysm from infundibular dilatation by volume rendering MRA. Techniques for improving depiction of the posterior communicating and anterior choroidal arteries

International Nuclear Information System (INIS)

Kato, Takaaki; Ito, Takeo; Hasunuma, Masahiro; Sakamoto, Yasuo; Kohama, Ikuhide; Yonemori, Terutake; Izumo, Masaki

2002-01-01

With the spread of brain dock procedures, non-invasive magnetic resonance angiography (MRA) is being utilized to broadly screen for brain blood vessel diseases. However, diagnosis of cerebral aneurysm can be difficult by routine MRA. In particular, differentiating aneurysms and infundibular dilatations (IDS) of the posterior communicating artery (PCoA) and anterior choroidal artery (AChA) at their bifurcations with the internal carotid artery (ICA) is extremely difficult and additional studies are frequently necessary. In this situation, three-dimensional computed tomography angiography (3D-CTA) and cerebral angiography have been utilized, but both techniques are invasive. Furthermore, images from cerebral angiography are only two-dimensional, and 3D-CTA requires differentiation between aneurysm and ID by observing configurational changes at the apex of the protrusion and by following gradual changes to the threshold. We therefore undertook the following steps to improve both depiction of the PCoA and AChA and differential diagnosis between aneurysm and ID: reduced slice thickness and increased number of excitations; utilized volume rendering methods to construct images; lowered thresholds for the beginning of the PCoA and AChA arteries, which represent the regions of interest. In all 11 cases that we operated on, cerebral aneurysms were diagnosed correctly and the minimum neck diameter of the cerebral aneurysm was 1.2 mm. In addition, the number of AChAs and PCoAs present in target MRA and in operational views were evaluated. In one case with an AChA aneurysm, a PCoA was not detected by target MRA, because the ICA deviated posterolaterally and pushed the PCoA to the posterior clinoid process, and blood flow was poor in operational views. In another 2 cases with AChA aneurysms, only one AChA was described in target MRA, whereas two aneurysms were present. However, one of these had a diameter less than 1 mm. In conclusion, this method offers an extremely useful aid

Safety and efficacy of aneurysm treatment with WEB in the cumulative population of three prospective, multicenter series

DEFF Research Database (Denmark)

Pierot, Laurent; Moret, Jacques; Barreau, Xavier

2018-01-01

BACKGROUND: Flow disruption with the WEB is an innovative endovascular approach for treatment of wide-neck bifurcation aneurysms. Initial studies have shown a low complication rate with good efficacy. PURPOSE: To report clinical and anatomical results of the WEB treatment in the cumulative popula...

Reproducibility of haemodynamical simulations in a subject-specific stented aneurysm model--a report on the Virtual Intracranial Stenting Challenge 2007.

Science.gov (United States)

Radaelli, A G; Augsburger, L; Cebral, J R; Ohta, M; Rüfenacht, D A; Balossino, R; Benndorf, G; Hose, D R; Marzo, A; Metcalfe, R; Mortier, P; Mut, F; Reymond, P; Socci, L; Verhegghe, B; Frangi, A F

2008-07-19

This paper presents the results of the Virtual Intracranial Stenting Challenge (VISC) 2007, an international initiative whose aim was to establish the reproducibility of state-of-the-art haemodynamical simulation techniques in subject-specific stented models of intracranial aneurysms (IAs). IAs are pathological dilatations of the cerebral artery walls, which are associated with high mortality and morbidity rates due to subarachnoid haemorrhage following rupture. The deployment of a stent as flow diverter has recently been indicated as a promising treatment option, which has the potential to protect the aneurysm by reducing the action of haemodynamical forces and facilitating aneurysm thrombosis. The direct assessment of changes in aneurysm haemodynamics after stent deployment is hampered by limitations in existing imaging techniques and currently requires resorting to numerical simulations. Numerical simulations also have the potential to assist in the personalized selection of an optimal stent design prior to intervention. However, from the current literature it is difficult to assess the level of technological advancement and the reproducibility of haemodynamical predictions in stented patient-specific models. The VISC 2007 initiative engaged in the development of a multicentre-controlled benchmark to analyse differences induced by diverse grid generation and computational fluid dynamics (CFD) technologies. The challenge also represented an opportunity to provide a survey of available technologies currently adopted by international teams from both academic and industrial institutions for constructing computational models of stented aneurysms. The results demonstrate the ability of current strategies in consistently quantifying the performance of three commercial intracranial stents, and contribute to reinforce the confidence in haemodynamical simulation, thus taking a step forward towards the introduction of simulation tools to support diagnostics and

TU-F-17A-03: A 4D Lung Phantom for Coupled Registration/Segmentation Evaluation

International Nuclear Information System (INIS)

Markel, D; El Naqa, I; Levesque, I

2014-01-01

Purpose: Coupling the processes of segmentation and registration (regmentation) is a recent development that allows improved efficiency and accuracy for both steps and may improve the clinical feasibility of online adaptive radiotherapy. Presented is a multimodality animal tissue model designed specifically to provide a ground truth to simultaneously evaluate segmentation and registration errors during respiratory motion. Methods: Tumor surrogates were constructed from vacuum sealed hydrated natural sea sponges with catheters used for the injection of PET radiotracer. These contained two compartments allowing for two concentrations of radiotracer mimicking both tumor and background signals. The lungs were inflated to different volumes using an air pump and flow valve and scanned using PET/CT and MRI. Anatomical landmarks were used to evaluate the registration accuracy using an automated bifurcation tracking pipeline for reproducibility. The bifurcation tracking accuracy was assessed using virtual deformations of 2.6 cm, 5.2 cm and 7.8 cm of a CT scan of a corresponding human thorax. Bifurcations were detected in the deformed dataset and compared to known deformation coordinates for 76 points. Results: The bifurcation tracking accuracy was found to have a mean error of −0.94, 0.79 and −0.57 voxels in the left-right, anterior-posterior and inferior-superior axes using a 1×1×5 mm3 resolution after the CT volume was deformed 7.8 cm. The tumor surrogates provided a segmentation ground truth after being registered to the phantom image. Conclusion: A swine lung model in conjunction with vacuum sealed sponges and a bifurcation tracking algorithm is presented that is MRI, PET and CT compatible and anatomically and kinetically realistic. Corresponding software for tracking anatomical landmarks within the phantom shows sub-voxel accuracy. Vacuum sealed sponges provide realistic tumor surrogate with a known boundary. A ground truth with minimal uncertainty is thus

EFFECTS OF PARENT ARTERY SEGMENTATION AND ANEURISMALWALL ELASTICITY ON PATIENT-SPECIFIC HEMODYNAMIC SIMULATIONS

Institute of Scientific and Technical Information of China (English)

CHEN Jia-liang; DING Guang-hong; YANG Xin-jian; LI Hai-yun

2011-01-01

It is well known that hemodynamics and wall tension play an important role in the formation,growth and rupture of aneurysms.In the present study,the authors investigated the influence of parent artery segmentation and aneurismal-wall elasticity on patient-specific hemodynamic simulations with two patient-specific eases of cerebral aneurysms.Realistic models of the aneurysms were constructed from 3-D angiography images and blood flow dynamics was studied under physiologically representative waveform of inflow.For each aneurysm three computational models were constructed:Model 1 with more extensive upstream parent artery with the rigid arterial and aneurismal wall,Model 2 with the partial upstream parent artery with the elastic arterial and aneurismal wall,Model 3 with more extensive upstream parent artery with the rigid wall for arterial wall far from the aneurysm and the elastic wall for arterial wall near the aneurysm.The results show that Model 1 could predict complex intra-aneurismal flow patterns and wall shear stress distribution in the aneurysm,but is unable to give aneurismal wall deformation and tension,Model 2 demonstrates aneurismal wall deformation and tension,but fails to properly model inflow pattern contributed by the upstream parent artery,resulting in local misunderstanding Wall Shear Stress (WSS) distribution,Model 3 can overcome limitations of the former two models,and give an overall and accurate analysis on intra-aneurismal flow patterns,wall shear stress distribution,aneurismal-wall deformation and tension.Therefore we suggest that the proper length of extensive upstream parent artery and aneuri-smal-wall elasticity should be considered carefully in establishing computational model to predict the intra-aneurismal hemodynamic and wall tension.

Inadequate communication between patients with unruptured cerebral aneurysms and neurosurgeons.

Science.gov (United States)

Saito, Makoto; Takahashi, Yoshimitsu; Yoshimura, Yayoi; Shima, Ayako; Morita, Akio; Houkin, Kiyohiro; Nakayama, Takeo; Nozaki, Kazuhiko

2012-01-01

Communication between patients with cerebral aneurysms and consulting neurosurgeons remains unstudied in Japan. The present clinical study surveyed patients with unruptured cerebral aneurysms and their neurosurgeons after explanation of the disease and its treatment options and expected outcomes in clinic visits using a one-page written questionnaire about treatment options and decisions given to patients and their neurosurgeons. The numbers of participating patients and neurosurgeons were 42 and 9, respectively, and 42 paired patient-neurosurgeon responses were obtained. Agreement was quite low (κ = 0.17-0.31 for 6-point Likert scale and κ = 0.44-0.67 for 2 category scale) regarding the "best" treatment for each patient as agreed on by the patient and neurosurgeon. Agreement in the understanding of treatment options and general application was unexpectedly low (κ = 0.12 and 0.01 for 6-point Likert scale and κ = not applicable and -0.03, respectively, for 2 category scale). Agreement tended to be higher between experienced neurosurgeons and patients than non-experienced neurosurgeons and patients. Patients estimated much higher risks of stroke or death after surgical intervention (p neurosurgeons.

Evaluation of the UF/NCI hybrid computational phantoms for use in organ dosimetry of pediatric patients undergoing fluoroscopically guided cardiac procedures

Science.gov (United States)

Marshall, Emily L.; Borrego, David; Tran, Trung; Fudge, James C.; Bolch, Wesley E.

2018-03-01

Epidemiologic data demonstrate that pediatric patients face a higher relative risk of radiation induced cancers than their adult counterparts at equivalent exposures. Infants and children with congenital heart defects are a critical patient population exposed to ionizing radiation during life-saving procedures. These patients will likely incur numerous procedures throughout their lifespan, each time increasing their cumulative radiation absorbed dose. As continued improvements in long-term prognosis of congenital heart defect patients is achieved, a better understanding of organ radiation dose following treatment becomes increasingly vital. Dosimetry of these patients can be accomplished using Monte Carlo radiation transport simulations, coupled with modern anatomical patient models. The aim of this study was to evaluate the performance of the University of Florida/National Cancer Institute (UF/NCI) pediatric hybrid computational phantom library for organ dose assessment of patients that have undergone fluoroscopically guided cardiac catheterizations. In this study, two types of simulations were modeled. A dose assessment was performed on 29 patient-specific voxel phantoms (taken as representing the patient’s true anatomy), height/weight-matched hybrid library phantoms, and age-matched reference phantoms. Two exposure studies were conducted for each phantom type. First, a parametric study was constructed by the attending pediatric interventional cardiologist at the University of Florida to model the range of parameters seen clinically. Second, four clinical cardiac procedures were simulated based upon internal logfiles captured by a Toshiba Infinix-i Cardiac Bi-Plane fluoroscopic unit. Performance of the phantom library was quantified by computing both the percent difference in individual organ doses, as well as the organ dose root mean square values for overall phantom assessment between the matched phantoms (UF/NCI library or reference) and the patient-specific

Endovascular treatment of PICA aneurysms

Energy Technology Data Exchange (ETDEWEB)

Mukonoweshuro, W.; Laitt, R.D.; Hughes, D.G. [Radiology Dept., Greater Manchester Neurosciences Unit, Hope Hospital, Salford, Manchester (United Kingdom)

2003-03-01

Endovascular treatment of aneurysms of the posterior inferior cerebellar artery (PICA) avoids manipulation of the brainstem or lower cranial nerves and should therefore carry a lower risk of neurological morbidity than surgical clipping. We reviewed our experience of 23 patients with PICA aneurysms treated by endovascular occlusion with Guglielmi detachable coils and documented their long-term outcome on follow-up. We observed a 28 day procedure-related neurological morbidity of 13% (3/23 patients). One patient suffered permanent neurological complications. There were no procedure-related deaths. None of our patients suffered a re-bleed from their treated aneurysms. Our series shows endovascular treatment of ruptured PICA aneurysms to be safe and effective. (orig.)

Multidisciplinary management of the patients with cerebral aneurysm - Preliminary experience

International Nuclear Information System (INIS)

Gomez Hoyos, Juan Fernando; Celis Mejia, Jorge Ignacio; Yepez Sanchez, Carlos Jaime; Duque Botero, Julieta

1998-01-01

A Actually, complex pathologies are treated according to a decision, which is adopted, by a group of specialists from different fields concerned to the same disease. The intention is to have success that is reflected in a low morbimortality and the most complete recovery to permit patients to return their previous life activities. Depending the status of each patient, type of aneurysm and its location, different techniques are performed to exclude them from circulation. Microneurosurgery, aneurysmatic sac embolization with platinum detachable coils and vessel originating aneurysm balloon occlusion The main objective of this work is to demonstrate that both microneurosurgery, classic technique in the cerebral aneurysms management but in continuing development, and endovascular therapy are not excluded, and their effectiveness depends in a strict selection criteria of patients and a comprehensive medical management before, during and after treatment by a multidisciplinary group. Also, to evaluate both techniques based on different indexes, including the ongoing evolution. In this work the preliminary experience of the Neurovascular Group at the Clinica Cardiovascular Santa Maria in Medellin, during the period of time from December 1996 until May 1998.45 patients with 47 aneurysm were treated 55.3% aneurysmatic lesions were treated by endovascular therapy and the remaining (44.7%) by microneurosurgery. 26 patients and same number of aneurysmatic lesions composed the endovascular group, the age range was between 20 and 70 years. 80.0% were women, 20.0% men. 53.8% complained from subarachnoid hemorrhage signs and symptoms. 36.0% were in a Hunt and Hess score scale of III and 84.7% complete success was achieved. 3 patients died, 2 of them were in IV and V Hunt and Hess score scale, respectively. The surgical group composed by 19 patients with 21 lesions and an age range between 31 and 78 years. 64.8% were women and 71,5% had confirmed diagnosis of subarachnoid hemorrhage

The intracranial aneurysm: cost-effective of the aneurysm intra-artery GDC embolization and the aneurysm incarcerated operation

International Nuclear Information System (INIS)

Pan Jie; Zhang Shizheng

2008-01-01

Objective: To evaluate the cost-effectiveness of the aneurysm intra-artery GDC embolization and the aneurysm clapping of intracranial aneurysm, and to give the instruction for the clinical practice. Methods: A case control study (1 vs. 1) was developed to evaluate the cost in hospital, the cost for return visit and the Quality-adusted Life-Year (QALY) and lifetime costs of the intra-artery GDC embolization and the aneurysm clapping of intraeranial aneurysm, under the matching of the age, sex, living place, the size and place of the aneurysm, and the Hunt and Hess score. Clinically effectiveness dates were derived from the medical records. Cost dates were derived from follow-up by telephones or letters. The correlation analysis was done with the SPSS 13.0. Results: The cost in hospital in AC group was (54 945±16 946)RMBs, which was higher than the ones in AE group (63 768±12 665) RMBs, (t=1.71, P 0.05). Conclusion: The results suggest that the two therapies have no difference in cost effective rate. Considering the physical and mental loss, the aneurysm intra-arteu GDC embolization was better than the aneurysm clapping for the patients with aneurysm that diameter less than 25 mm. (authors)

Familial Thoracic Aortic Aneurysm with Dissection Presenting as Flash Pulmonary Edema in a 26-Year-Old Man

Directory of Open Access Journals (Sweden)

Sabry Omar

2014-01-01

Full Text Available We are reporting a case of familial thoracic aortic aneurysm and dissection in a 26-year-old man with no significant past medical history and a family history of dissecting aortic aneurysm in his mother at the age of 40. The patient presented with cough, shortness of breath, and chest pain. Chest X-ray showed bilateral pulmonary infiltrates. CT scan of the chest showed a dissection of the ascending aorta. The patient underwent aortic dissection repair and three months later he returned to our hospital with new complaints of back pain. CT angiography showed a new aortic dissection extending from the left carotid artery through the bifurcation and into the iliac arteries. The patient underwent replacement of the aortic root, ascending aorta, total aortic arch, and aortic valve. The patient recovered well postoperatively. Genetic studies of the patient and his children revealed no mutations in ACTA2, TGFBR1, TGFBR2, TGFB2, MYH11, MYLK, SMAD3, or FBN1. This case report focuses on a patient with familial TAAD and discusses the associated genetic loci and available screening methods. It is important to recognize potential cases of familial TAAD and understand the available screening methods since early diagnosis allows appropriate management of risk factors and treatment when necessary.

Closed-Cell Stent-Assisted Coiling of Intracranial Aneurysms: Evaluation of Changes in Vascular Geometry Using Digital Subtraction Angiography.

Science.gov (United States)

Beller, Ebba; Klopp, David; Göttler, Jens; Kaesmacher, Johannes; Zimmer, Claus; Kirschke, Jan S; Prothmann, Sascha

2016-01-01

Stent-assisted coil embolization (SACE) plays an important role in the treatment of intracranial aneurysms. The purpose of this study was to investigate geometrical changes caused by closed-cell design stents in bifurcation and sidewall aneurysms. 31 patients with 34 aneurysms underwent SACE with closed-cell design stents. Inflow angle α, determined by aneurysm neck and afferent vessel, and angle between afferent and efferent vessel close to (δ1), respectively, more remote from the aneurysm neck (δ2) were graphically determined in 2D angiography projections. Stent assisted coiling resulted in a significant increase of all three angles from a mean value (±SEM) of α = 119° (±6.5°) pretreatment to 130° (±6.6°) posttreatment (P ≤ .001), δ1 = 129° (±6.4°) to 139° (±6.1°), (P ≤ .001) and δ2 = 115° (±8.4°) to 126° (±7.5°), (P ≤ .01). Angular change of δ1 in AcomA aneurysms was significant greater compared to sidewall aneurysms (26°±4.9° versus 8°± 2.3°, P ≤ .05). The initial angle of δ1 and δ2 revealed a significantly inverse relationship to the angle increase (δ1: r = -0.41, P ≤ .05 and δ2: r = -0.47, P ≤ .01). Moreover, angle δ1 was significantly higher in unruptured compared to ruptured aneurysms (135°±7.1° versus 103°±10.8°, P ≤ .05). Stent deployment modulates the geometry of the aneurysm-vessel complex, which may lead to favorable hemodynamic changes more similar to unruptured than to ruptured aneurysms. Our findings also suggest that the more acute-angled aneurysm-vessel anatomy, the larger the angular change. Further studies are needed to investigate whether these changes improve the clinical outcome.

Closed-Cell Stent-Assisted Coiling of Intracranial Aneurysms: Evaluation of Changes in Vascular Geometry Using Digital Subtraction Angiography.

Directory of Open Access Journals (Sweden)

Ebba Beller

Full Text Available Stent-assisted coil embolization (SACE plays an important role in the treatment of intracranial aneurysms. The purpose of this study was to investigate geometrical changes caused by closed-cell design stents in bifurcation and sidewall aneurysms.31 patients with 34 aneurysms underwent SACE with closed-cell design stents. Inflow angle α, determined by aneurysm neck and afferent vessel, and angle between afferent and efferent vessel close to (δ1, respectively, more remote from the aneurysm neck (δ2 were graphically determined in 2D angiography projections.Stent assisted coiling resulted in a significant increase of all three angles from a mean value (±SEM of α = 119° (±6.5° pretreatment to 130° (±6.6° posttreatment (P ≤ .001, δ1 = 129° (±6.4° to 139° (±6.1°, (P ≤ .001 and δ2 = 115° (±8.4° to 126° (±7.5°, (P ≤ .01. Angular change of δ1 in AcomA aneurysms was significant greater compared to sidewall aneurysms (26°±4.9° versus 8°± 2.3°, P ≤ .05. The initial angle of δ1 and δ2 revealed a significantly inverse relationship to the angle increase (δ1: r = -0.41, P ≤ .05 and δ2: r = -0.47, P ≤ .01. Moreover, angle δ1 was significantly higher in unruptured compared to ruptured aneurysms (135°±7.1° versus 103°±10.8°, P ≤ .05.Stent deployment modulates the geometry of the aneurysm-vessel complex, which may lead to favorable hemodynamic changes more similar to unruptured than to ruptured aneurysms. Our findings also suggest that the more acute-angled aneurysm-vessel anatomy, the larger the angular change. Further studies are needed to investigate whether these changes improve the clinical outcome.

Spontaneous intracranial hemorrhage and multiple intracranial aneurysms in a patient with Roberts/SC phocomelia syndrome.

Science.gov (United States)

Wang, Anthony C; Gemmete, Joseph J; Keegan, Catherine E; Witt, Cordelie E; Muraszko, Karin M; Than, Khoi D; Maher, Cormac O

2011-11-01

Roberts/SC phocomelia syndrome (RBS) is a rare but distinct genetic disorder with an autosomal recessive inheritance pattern. It has been associated with microcephaly, craniofacial malformation, cavernous hemangioma, encephalocele, and hydrocephalus. There are no previously reported cases of RBS with intracranial aneurysms. The authors report on a patient with a history of RBS who presented with a spontaneous posterior fossa hemorrhage. Multiple small intracranial aneurysms were noted on a preoperative CT angiogram. The patient underwent emergency craniotomy for evacuation of the hemorrhage. A postoperative angiogram confirmed the presence of multiple, distal small intracranial aneurysms.

CHARACTERIZATION OF PATIENTS WITH ENDOVASCULAR TREATMENT OF DISSECTING ANEURYSMS OF POSTERIOR CEREBRAL CIRCULATION IN CARTAGENA DE INDIAS

OpenAIRE

Rueda-Tamayo Leidy; Almeida-Pérez Rafael; De la Rosa-Manjarrez Ginna; Orozco-Gómez Fernando; Carrasquilla-Meléndez Rubén

2015-01-01

Introduction: the intracraneal aneurysms are local and permanent dilations in the artery. Objective: to describe the clinical, imagenologic and effectiveness of endovascular treatment in terms of its independence and mortality in patients with dissecting aneurysms of posterior cerebral circulation in Cartagena. Methods: a descriptive study was carried out with patients 18 years or older with a diagnosis of dissecting aneurysms of posterior cerebral circulation who received ...

Surgical treatment of Marfan patients with aneurysms and dissection of the proximal aorta.

Science.gov (United States)

Mingke, D; Dresler, C; Pethig, K; Heinemann, M; Borst, H G

1998-02-01

The authors retrospectively analyzed early and late results of surgical treatment for 79 Marfan patients with aneurysms and dissection of the proximal aorta. From September 1979 to February 1996, 79 patients with Marfan syndrome underwent aortic root replacement using composite grafts (n=68, Bentall-technique 63, button-technique 5), and ascending aortic replacement with a valve-sparing procedure (n=11). There were 12 patients (15.2%) who simultaneously received partial or total arch replacement. 55 patients (69.6%) were male, and 24 female (30.4%). The average age was 33.8 years. Forty-one patient (51.9%) had non-dissecting aneurysms while the remaining 38 patients suffered from either acute (24.0%) or chronic aortic dissection (24.0%). The aortic valve was involved in 97.5% of all cases. The total early mortality (valve-sparing operation and in those with chronic aortic dissection. The follow-up rate was 98.7%. During a mean follow-up of 68+/-25 months 10 patients (13.3%) died and cardiac complications were a common cause of the late deaths. There was no late mortality in the valve-sparing operations during a mean follow-up period of 8+/-6 months, however, 1 required valve replacement. 19 (25.3%) of the 75 patients surviving late have undergone 25 secondary operations on the cardiovascular system. Reoperations at aortic sites distant from the original were much more frequent after primary repair for acute and chronic dissection when compared to non-dissecting aneurysms (pMarfan-patients with non-dissecting and dissecting aneurysms of the aortic root. Our early experience in 11 patients with valve-sparing procedures indicated that this,variant may be the better choice in selected patients.

Intra-aneurysmal flow disruption after implantation of the Medina® Embolization Device depends on aneurysm neck coverage.

Science.gov (United States)

Frölich, Andreas Maximilian; Nawka, Marie Teresa; Ernst, Marielle; Frischmuth, Isabell; Fiehler, Jens; Buhk, Jan-Hendrik

2018-01-01

Flow disruption achieved by braided intrasaccular implants is a novel treatment strategy for cerebrovascular aneurysms. We hypothesized that the degree of intra-aneurysmal flow disruption can be quantified in vitro and is influenced by device position across the aneurysm neck. We tested this hypothesis using the Medina® Embolization Device (MED). Ten different patient-specific elastic vascular models were manufactured. Models were connected to a pulsatile flow circuit, filled with a blood-mimicking fluid and treated by two operators using a single MED. Intra-aneurysmal flow velocity was measured using conventional and high-frequency digital subtraction angiography (HF-DSA) before and after each deployment. Aneurysm neck coverage by the implanted devices was assessed with flat detector computed tomography on a three-point Likert scale. A total of 80 individual MED deployments were performed by the two operators. The mean intra-aneurysmal flow velocity reduction after MED implantation was 33.6% (27.5-39.7%). No significant differences in neck coverage (p = 0.99) or flow disruption (p = 0.84) were observed between operators. The degree of flow disruption significantly correlated with neck coverage (ρ = 0.42, 95% CI: 0.21-0.59, p = 0.002) as well as with neck area (ρ = -0,35, 95% CI: -0.54 --0.13, p = 0.024). On multiple regression analysis, both neck coverage and total neck area were independent predictors of flow disruption. The degree of intra-aneurysmal flow disruption after MED implantation can be quantified in vitro and varies considerably between different aneurysms and different device configurations. Optimal device coverage across the aneurysm neck improves flow disruption and may thus contribute to aneurysm occlusion.

Ruptured intracranial aneurysm in patients with osteogenesis imperfecta: 2 familial cases and a systematic review of the literature.

Science.gov (United States)

Gaberel, T; Rochey, A; di Palma, C; Lucas, F; Touze, E; Emery, E

2016-12-01

Osteogenesis imperfecta is an inherited connective tissue disorder that causes bone fragility. Vascular complications have been described, but only few cases of ruptured intracranial aneurysm have been reported. We first described 2 familial cases of ruptured intracranial aneurysm and then conducted a systematic review of the literature. A mother and her daughter with a typical history of osteogenesis imperfecta presented with subarachnoid hemorrhage, which was related to a posterior communicating artery aneurysm in both cases. The mother had early rebleeding and died. The aneurysm was excluded by coiling in the daughter. Despite occurrence of hydrocephalus and delayed cerebral ischemia, she had an excellent functional outcome. A systematic review of the literature identified seven additional cases. None of the cases were in fact familial. All patients had a previous medical history of multiple fractures. Seven aneurysms were resolved, three by surgical clipping and four by endovascular procedure. No periprocedural complication was reported. One patient died prematurely and 6 experienced good functional outcome. We report the first familial cases of aneurysmal subarachnoid hemorrhage in osteogenesis imperfecta patients. Intracranial aneurysms are probably linked to a collagen pathology, which is at the origin of osteogenesis imperfecta. In cases of aneurysmal subarachnoid hemorrhage in an osteogenesis imperfecta family, intracranial aneurysm screenings in the relatives showing osteogenesis imperfecta should be considered. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Glutathione system participation in thoracic aneurysms from patients with Marfan syndrome.

Science.gov (United States)

Zúñiga-Muñoz, Alejandra María; Pérez-Torres, Israel; Guarner-Lans, Verónica; Núñez-Garrido, Elías; Velázquez Espejel, Rodrigo; Huesca-Gómez, Claudia; Gamboa-Ávila, Ricardo; Soto, María Elena

2017-05-01

Aortic dilatation in Marfan syndrome (MFS) is progressive. It is associated with oxidative stress and endothelial dysfunction that contribute to the early acute dissection of the vessel and can result in rupture of the aorta and sudden death. We evaluated the participation of the glutathione (GSH) system, which could be involved in the mechanisms that promote the formation and progression of the aortic aneurysms in MFS patients. Aortic aneurysm tissue was obtained during chest surgery from eight control subjects and 14 MFS patients. Spectrophotometrical determination of activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR), lipid peroxidation (LPO) index, carbonylation, total antioxidant capacity (TAC), and concentration of reduced and oxidized glutathione (GSH and GSSG respectively), was performed in the homogenate from aortic aneurysm tissue. LPO index, carbonylation, TGF-β1, and GR activity were increased in MFS patients (p < 0.04), while TAC, GSH/GSSG ratio, GPx, and GST activity were significantly decreased (p < 0.04). The depletion of GSH, in spite of the elevated activity of GR, not only diminished the activity of GSH-depend GST and GPx, but increased LPO, carbonylation and decreased TAC. These changes could promote the structural and functional alterations in the thoracic aorta of MFS patients.

Epidemiology of aortic disease - aneurysm, dissection, occlusion

International Nuclear Information System (INIS)

Steckmeier, B.

2001-01-01

The physiological infrarenal aortic diameter varies between 12.4 mm in women an 27.6 mm in men. As defined, an aneurysmatic dilatation begins with 29 mm. According to that, 9% of all people above the age of 65 are affected by an abdominal aortic aneurysm (AAA). Compared with the female sex, the male sex predominates at a rate of about 5:1. The disease is predominant in men of the white race. In black men, black and white women the incidence of AAA is identical. 38 to 50 percent of the AAA patients (patients) suffer from hypertension, 33 to 60% from coronary, 28% from cerebrovascular and 25% from peripheral occlusive disease. The AAA expansion rate varies between 0.2 and 0.8 cm per year and is exponential from a diameter of 5 cm on. In autopsy studies, the rupture rates with AAA diameters of 7 cm were below 5%, 39% and 65%, respecitvely. 70% of the AAA patients do not die of a rupture, but of a cardiac disease. Serum markers, such as metalloproteinases and procollagen peptides are significantly increased in AAA patients. Thoraco-abdominal aneurysms (TAA) make up only 2 to 5% of all degenerative aneurysms. 20 to 30% of the TAA patients are also affected by an AAA. 80% of the TAA are degenerative, 15 to 20% are a consequence of the chronic dissection - including 5% of Marfan patients -, 2% occur in case of infections and 1 to 2% in case of aortitis. The TAA incidence in 100,000 person-years is 5.9% during a monitoring period of 30 years. In case of TAA, an operation is indicated with a maximum diameter of 5.5 to 6 cm and more and, in case of a Marfan's syndrome (incidence of 1:10,000), with a maximum diameter of 5.5 cm and more. With regard to aorto-iliac occlusive diseases, there are defined 3 types of distribution. Type I refers to the region of the bifurcation itself. Type II defines the diffuse aortoiliac spread of the disease. Type III designates multiple-level occlusions also beyond the inguinal ligament. Type I patients in most cases are female and more

A prospective clinical, economic, and quality-of-life analysis comparing endovascular aneurysm repair (EVAR), open repair, and best medical treatment in high-risk patients with abdominal aortic aneurysms suitable for EVAR: the Irish patient trial.

LENUS (Irish Health Repository)

Hynes, Niamh

2007-12-01

To report the results of a trial comparing endovascular aneurysm repair (EVAR) to open repair (OR) and best medical therapy (BMT) involving high-risk patients with abdominal aortic aneurysms (AAA) suitable for EVAR.

The result of surgical treatment in patients with cerebral aneurysms in Maharaj Nakorn Chiang Mai Hospital: a report of 225 cases.

Science.gov (United States)

Watcharasaksilp, Wanarak; Limpastan, Kriengsak; Norasathada, Tanya; Vaniyapong, Tanat

2013-07-01

Evaluate the result of intracranial aneurysm surgery in Maharaj Nakorn Chiang Mai Hospital. A retrospective study ofpatients who underwent surgery for intracranial aneurysms between 2003 and 2007. The patients'age, gender, signs and symptoms, CT brain findings, Subarachnoid hemorrhage (SAH), World Federation of Neurosurgical Society grading (WFNS), and aneurysm location were studied and correlated with outcome after surgery. Two hundred twenty five patients ofintracranial aneurysm were operated on between 2003 and 2007. Two hundred nine patients (92%) had anterior circulation aneurysms and 18 (8%) had posterior circulation aneurysms. The outcome, as evaluated by Glasgow Outcome Scale (GOS), showed good recovery and moderate disability patients (142, 62.9%) were classified as favorable outcome group whereas patients with severe disability, vegetative state, and dead (83, 36.9%) were classified as unfavorable outcome. According to WFNS grading, the patients with unruptured aneurysm and WFNS grade 1-2 had favorable outcome in 116 patients (78.37%) and unfavorable outcome in 32 patients (21.62%). Whereas the patients with WFNS grade 3-5 had favorable outcome in 32 patients (33.76%) and unfavorable outcome in 51 patients (66.23%). This study of 225 cases revealed 142 cases with favorable outcome and 83 cases with unfavorable outcome. Factors that affected the outcome were WFNS grading and age.

Size ratio performance in detecting cerebral aneurysm rupture status is insensitive to small vessel removal.

Science.gov (United States)

Lauric, Alexandra; Baharoglu, Merih I; Malek, Adel M

2013-04-01

The variable definition of size ratio (SR) for sidewall (SW) vs bifurcation (BIF) aneurysms raises confusion for lesions harboring small branches, such as carotid ophthalmic or posterior communicating locations. These aneurysms are considered SW by many clinicians, but SR methodology classifies them as BIF. To evaluate the effect of ignoring small vessels and SW vs stringent BIF labeling on SR ruptured aneurysm detection performance in borderline aneurysms with small branches, and to reconcile SR-based labeling with clinical SW/BIF classification. Catheter rotational angiographic datasets of 134 consecutive aneurysms (60 ruptured) were automatically measured in 3-dimensional. Stringent BIF labeling was applied to clinically labeled aneurysms, with 21 aneurysms switching label from SW to BIF. Parent vessel size was evaluated both taking into account, and ignoring, small vessels. SR was defined accordingly as the ratio between aneurysm and parent vessel sizes. Univariate and multivariate statistics identified significant features. The square of the correlation coefficient (R(2)) was reported for bivariate analysis of alternative SR calculations. Regardless of SW/BIF labeling method, SR was equally significant in discriminating aneurysm ruptured status (P analysis of alternative SR had a high correlation of R(2) = 0.94 on the whole dataset, and R = 0.98 on the 21 borderline aneurysms. Ignoring small branches from SR calculation maintains rupture status detection performance, while reducing postprocessing complexity and removing labeling ambiguity. Aneurysms adjacent to these vessels can be considered SW for morphometric analysis. It is reasonable to use the clinical SW/BIF labeling when using SR for rupture risk evaluation.

Transcatheter Embolization of a Renal Artery Aneurysm Using Ethylene Vinyl Alcohol Copolymer

International Nuclear Information System (INIS)

Rautio, Riitta; Haapanen, Arto

2007-01-01

Our aim was to treat a clinically silent renal artery aneurysm. The patient was a 76-year-old man with elevated prostate-specific antigen and prostata biopsies with a gradus II-III adenocarcinoma who was incidentally found to have an aneurysm in his right renal artery. We performed a successful transcatheter embolization of the aneurysm using ethylene vinyl alcohol copolymer (Onyx). To avoid migration of the liquid material into the parent artery, a balloon was inflated in the orifice of the neck of the aneurysm while the liquid was injected. Five-month follow-up computed tomography (CT) imaging confirmed total occlusion of the aneurysm

Abciximab for thrombolysis during intracranial aneurysm coiling

International Nuclear Information System (INIS)

Gralla, Jan; Rennie, Adam T.M.; Corkill, Rufus A.; Lalloo, Shivendra T.; Molyneux, Andrew; Byrne, James V.; Kuker, Wilhem

2008-01-01

Thrombotic events are a common and severe complication of endovascular aneurysm treatment with significant impact on patients' outcome. This study evaluates risk factors for thrombus formation and assesses the efficacy and safety of abciximab for clot dissolution. All patients treated with abciximab during (41 patients) or shortly after (22 patients) intracranial aneurysm coil embolisation were retrieved from the institutional database (2000 to 2007, 1,250 patients). Sixty-three patients (mean age, 55.3 years, ±12.8) had received either intra-arterial or intravenous abciximab. Risk factors for clot formation were assessed and the angiographic and clinical outcome evaluated. No aneurysm rupture occurred during or after abciximab application. The intra-procedural rate of total recanalisation was 68.3%. Thromboembolic complications were frequently found in aneurysms of the Acom complex and of the basilar artery, whilst internal carotid artery aneurysms were underrepresented. Two patients died of treatment-related intracranial haemorrhages into preexisting cerebral infarcts. Two patients developed a symptomatic groin haematoma. Abciximab is efficacious and safe for thrombolysis during and after endovascular intracranial aneurysm treatment in the absence of preexisting ischaemic stroke. (orig.)

Surgical management of recurrent intracranial aneurysms after embolization

Directory of Open Access Journals (Sweden)

Hua-wei WANG

2015-03-01

Full Text Available Background Endovascular therapy is the first treatment choice for intracranial aneurysms currently, but it has a high recurrence rate. Some patients require surgical clipping because of the difficulty of re-embolization. This study retrospectively analyzed the clinical data of 11 cases who underwent clipping operation because of the recurrence after endovascular therapy. Combining with domestic and foreign related literatures, this paper discusses the principles and techniques of surgical treatment for recurrent aneurysms.  Methods There were a total of 11 patients with 12 recurrent aneurysms after embolization, including 3 anterior communicating artery (ACoA aneurysms, 3 middle cerebral artery (MCA aneurysms, 2 posterior communicating artery (PCoA aneurysms, one anterior cerebral artery (ACA aneurysm, one vertebral artery (VA aneurysm, one basilar tip aneurysm and one superior cerebellar artery (SCA aneurysm. There were 7 small aneurysms and 4 large aneurysms. All patients underwent surgical clipping under microscope. After operation, 11 aneurysms were complete clipped, and one was proximally blocked. The coils were reserved in 7 aneurysms, and were removed or partially removed in 5 aneurysms.  Results All patients were followed up for an average of 22 months after surgery. There were 9 cases (9/11 with the Glasgow Outcome Scale (GOS score improved or remaining unchanged compared with preoperation. One of them presented left limb weakness after operation, with the muscle strength Grade 3, while recovered to Grade 4-5 on discharge. The other 2 patients died after surgery. One case had a critical condition before surgery, and the other was secondary to thrombosis and pneumonia. Both of them had a GOS score of 2 when discharged, and died after discharge.  Conclusions There is high surgical difficulty in recurrent aneurysms, however, with adequate preoperative evaluation and surgical design, it can still promise safe and effective results

Endovascular coil embolization for anterior choroidal artery aneurysms

Energy Technology Data Exchange (ETDEWEB)

Kim, Byung Moon; Chung, Eun Chul [Sungkyunkwan University School of Medicine, Department of Radiology, Kangbuk Samsung Hospital, Seoul (Korea); Kim, Dong Ik; Kim, Dong Joon; Suh, Sang Hyun [Yonsei University College of Medicine, Department of Radiology, Seoul (Korea); Kim, Sun Yong [Ajou University College of Medicine, Department of Radiology, Suwon (Korea); Shin, Yong Sam [Ajou University College of Medicine, Department of Neurosurgery, Suwon (Korea); Park, Sung Il [Soonchunhyang University College of Medicine, Department of Radiology, Bucheon Hospital, Bucheon (Korea); Choi, Chun Sik; Won, Yu.Sam [Sungkyunkwan University School of Medicine, Department of Neurosurgery, Kangbuk Samsung Hospital, Seoul (Korea)

2008-03-15

We retrospectively evaluated the ischemic complications related to the anterior choroidal artery (AChA) and clinical outcome after coiling of AChA aneurysms. We included 37 patients (27 with subarachnoid hemorrhage, 10 without) harboring 38 AChA aneurysms (23 ruptured, 15 unruptured) who were treated by coiling at four institutions. Ischemic complications related to the AChA and clinical outcomes were retrospectively evaluated. Intraprocedural transient AChA occlusion occurred in five aneurysms, all of which had AChA incorporated into the aneurysm neck. Two of the five patients suffered postprocedural transient contralateral hemiparesis, but recovered completely. The remaining three patients had no postprocedural symptoms. Incidence of transient AChA occlusion was significantly higher in those aneurysms in which the AChA was incorporated into aneurysm neck (group 2) than in those in which the AChA was not incorporated (group 1). Of the 37 patients, 31 (83.8%) had good recoveries (modified Rankin scale score 0-2). Two patients died from the consequences of subarachnoid hemorrhage. During follow-up for a mean of 27 months (range 4-72 months), none of the 35 living patients re-bled. A total of 29 aneurysms in 28 patients were followed-up angiographically. Recurrences were found in 5 of the 29 aneurysms during follow-up (mean 18 months, range 6-45 months). Re-embolization achieved near complete occlusion of two recurrent aneurysms, both of which were still stable at the time of the next two follow-up angiographies. The other three recurrent aneurysms were not retreated due to the small size of the recurrences. Coiling of AChA aneurysms resulted in good outcomes without AChA-related permanent ischemic complications. Transient AChA occlusion, potentially associated with ischemic complications, was significantly more frequent in the aneurysm in which the AChA was incorporated into the aneurysm neck. (orig.)

SU-F-I-37: How Fat Distribution and Table Height Affect Estimates of Patient Size in CT Scanning: A Phantom Study

Energy Technology Data Exchange (ETDEWEB)

Silosky, M; Marsh, R [University of Colorado School of Medicine, Aurora, CO (United States)

2016-06-15

Purpose: Localizer projection radiographs acquired prior to CT scans are used to estimate patient size, affecting the function of Automatic Tube Current Modulation (ATCM) and hence CTDIvol and SSDE. Due to geometric effects, the projected patient size varies with scanner table height and with the orientation of the localizer (AP versus PA). This study sought to determine if patient size estimates made from localizer scans is affected by variations in fat distribution, specifically when the widest part of the patient is not at the geometric center of the patient. Methods: Lipid gel bolus material was wrapped around an anthropomorphic phantom to simulate two different body mass distributions. The first represented a patient with fairly rigid fat and had a generally oval shape. The second was bell-shaped, representing corpulent patients more susceptible to gravity’s lustful tug. Each phantom configuration was imaged using an AP localizer and then a PA localizer. This was repeated at various scanner table heights. The width of the phantom was measured from the localizer and diagnostic images using in-house software. Results: 1) The projected phantom width varied up to 39% as table height changed.2) At some table heights, the width of the phantom, designed to represent larger patients, exceeded the localizer field of view, resulting in an underestimation of the phantom width.3) The oval-shaped phantom approached a normalized phantom width of 1 at a table height several centimeters lower (AP localizer) or higher (PA localizer) than did the bell-shaped phantom. Conclusion: Accurate estimation of patient size from localizer scans is dependent on patient positioning with respect to scanner isocenter and is limited in large patients. Further, patient size is more accurately measured on projection images if the widest part of the patient, rather than the geometric center of the patient, is positioned at scanner isocenter.

Individualized management for intracranial vertebral artery dissecting aneurysms

Directory of Open Access Journals (Sweden)

SHANG Yan-guo

2012-02-01

Full Text Available Objective To discuss the individualized management strategy for intracranial vertebral artery dissecting aneurysms. Methods Eighteen patients with intracranial vertebral artery dissecting aneurysms were treated with different surgical methods. Results Eighteen patients underwent different surgical treatment. Five patients underwent complete occlusion of the aneurysm and parent artery by coiling, 5 were treated by stent -assisted coiling (3 densely packed coiling and 2 non-densely packed coiling, 4 underwent stent-only therapy and 3 of them presented hemodynamic improvement after surgery, 3 were treated by direct surgical clipping, and 1 underwent occipital artery-posterior inferior cerebellar artery bypass. Two aneurysms ruptured immaturely, in which one patient died on the third day after operation and one patient occurred moderate disablity. Only 1 patient who underwent complete occlusion of aneurysm and parent artery presented temporarily ischemic symptoms. No adverse effects were seen in other patients. Seventeen patients were followed up for 1 month to 3 years, and all the aneurysms were stable. Conclusion There are many kinds of therapeutic methods for intracranial vertebral artery dissecting aneurysms. The patients should be treated according to several factors such as the clinical manifestations, aneurysm configuration, and relationship with the posterior inferior cerebellar artery. The treatment should be individualized.

Individualized adjustments to reference phantom internal organ dosimetry—scaling factors given knowledge of patient external anatomy

Science.gov (United States)

Wayson, Michael B.; Bolch, Wesley E.

2018-04-01

Internal radiation dose estimates for diagnostic nuclear medicine procedures are typically calculated for a reference individual. Resultantly, there is uncertainty when determining the organ doses to patients who are not at 50th percentile on either height or weight. This study aims to better personalize internal radiation dose estimates for individual patients by modifying the dose estimates calculated for reference individuals based on easily obtainable morphometric characteristics of the patient. Phantoms of different sitting heights and waist circumferences were constructed based on computational reference phantoms for the newborn, 10 year-old, and adult. Monoenergetic photons and electrons were then simulated separately at 15 energies. Photon and electron specific absorbed fractions (SAFs) were computed for the newly constructed non-reference phantoms and compared to SAFs previously generated for the age-matched reference phantoms. Differences in SAFs were correlated to changes in sitting height and waist circumference to develop scaling factors that could be applied to reference SAFs as morphometry corrections. A further set of arbitrary non-reference phantoms were then constructed and used in validation studies for the SAF scaling factors. Both photon and electron dose scaling methods were found to increase average accuracy when sitting height was used as the scaling parameter (~11%). Photon waist circumference-based scaling factors showed modest increases in average accuracy (~7%) for underweight individuals, but not for overweight individuals. Electron waist circumference-based scaling factors did not show increases in average accuracy. When sitting height and waist circumference scaling factors were combined, modest average gains in accuracy were observed for photons (~6%), but not for electrons. Both photon and electron absorbed doses are more reliably scaled using scaling factors computed in this study. They can be effectively scaled using sitting

Individualized adjustments to reference phantom internal organ dosimetry-scaling factors given knowledge of patient external anatomy.

Science.gov (United States)

Wayson, Michael B; Bolch, Wesley E

2018-04-13

Internal radiation dose estimates for diagnostic nuclear medicine procedures are typically calculated for a reference individual. Resultantly, there is uncertainty when determining the organ doses to patients who are not at 50th percentile on either height or weight. This study aims to better personalize internal radiation dose estimates for individual patients by modifying the dose estimates calculated for reference individuals based on easily obtainable morphometric characteristics of the patient. Phantoms of different sitting heights and waist circumferences were constructed based on computational reference phantoms for the newborn, 10 year-old, and adult. Monoenergetic photons and electrons were then simulated separately at 15 energies. Photon and electron specific absorbed fractions (SAFs) were computed for the newly constructed non-reference phantoms and compared to SAFs previously generated for the age-matched reference phantoms. Differences in SAFs were correlated to changes in sitting height and waist circumference to develop scaling factors that could be applied to reference SAFs as morphometry corrections. A further set of arbitrary non-reference phantoms were then constructed and used in validation studies for the SAF scaling factors. Both photon and electron dose scaling methods were found to increase average accuracy when sitting height was used as the scaling parameter (~11%). Photon waist circumference-based scaling factors showed modest increases in average accuracy (~7%) for underweight individuals, but not for overweight individuals. Electron waist circumference-based scaling factors did not show increases in average accuracy. When sitting height and waist circumference scaling factors were combined, modest average gains in accuracy were observed for photons (~6%), but not for electrons. Both photon and electron absorbed doses are more reliably scaled using scaling factors computed in this study. They can be effectively scaled using sitting

Microneurosurgical management of anterior choroid artery aneurysms.

Science.gov (United States)

Lehecka, Martin; Dashti, Reza; Laakso, Aki; van Popta, Jouke S; Romani, Rossana; Navratil, Ondrej; Kivipelto, Leena; Kivisaari, Riku; Foroughi, Mansoor; Kokuzawa, Jouji; Lehto, Hanna; Niemelä, Mika; Rinne, Jaakko; Ronkainen, Antti; Koivisto, Timo; Jääskelainen, Juha E; Hernesniemi, Juha

2010-05-01

Anterior choroid artery aneurysms (AChAAs) constitute 2%-5% of all intracranial aneurysms. They are usually small, thin walled with one or several arteries originating at their base, and often associated with multiple aneurysms. In this article, we review the practical microsurgical anatomy, the preoperative imaging, surgical planning, and the microneurosurgical steps in the dissection and the clipping of AChAAs. This review, and the whole series on intracranial aneurysms (IAs), are mainly based on the personal microneurosurgical experience of the senior author (J.H.) in two Finnish centers (Helsinki and Kuopio) that serve, without patient selection, the catchment area in Southern and Eastern Finland. These two centers have treated more than 10,000 patients with IAs since 1951. In the Kuopio Cerebral Aneurysm Database of 3005 patients with 4253 IAs, 831 patients (28%) had altogether 980 internal carotid artery (ICA) aneurysms, of whom 95 patients had 99 (2%) AChAAs. Ruptured AChAAs, found in 39 patients (41%), with median size of 6 mm (range = 2-19 mm), were associated with intracerebral hematoma (ICH) in only 1 (3%) patient. Multiple aneurysms were seen in 58 (61%) patients. The main difficulty in microneurosurgical management of AChAAs is to preserve flow in the anterior choroid artery originating at the base and often attached to the aneurysm dome. This necessitates perfect surgical strategy based on preoperative knowledge of 3 dimensional angioarchitecture and proper orientation during the microsurgical dissection. Copyright © 2010 Elsevier Inc. All rights reserved.

Evaluation of Aneurysm Neck Angle Change After Endovascular Aneurysm Repair Clinical Investigations

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Le, Trong Binh; Moon, Mi Hyoung [Inha University Hospital, Endovascular Training Center (Korea, Republic of); Jeon, Yong Sun, E-mail: radjeon@inha.ac.kr [Inha University Hospital, Inha University School of Medicine, Department of Radiology (Korea, Republic of); Hong, Kee Chun [Inha University School of Medicine, Department of Vascular Surgery (Korea, Republic of); Cho, Soon Gu [Inha University Hospital, Inha University School of Medicine, Department of Radiology (Korea, Republic of); Park, Keun-Myoung [Inha University School of Medicine, Department of Vascular Surgery (Korea, Republic of)

2016-05-15

PurposeTo evaluate the aneurysm neck angle changes and post-endovascular aneurysm repair (EVAR) complications.MethodsWe retrospectively analyzed 72 cases of elective EVAR for abdominal aortic aneurysm among 109 consecutive cases from December 2005 to April 2014. Patients were divided into angulated and non-angulated groups. The angulated group was defined as neck angulation ≥60°. Neck angle was evaluated pre- and post-EVAR during short- (within 1 month), mid- (3–6 months), and long-term (>1 year) follow-up. Aneurysm sac diameter change, aneurysm neck morphology other than angulation, endoleaks, and other post-procedural complications were also documented.ResultsA total of 34 patients were enrolled in the angulated group. There were no statistical differences in age, sex, follow-up duration, and aneurysm neck profile between the two groups (p > 0.05). Both groups showed statistically significant and consistent decreases in angulation during the follow-up period (p < 0.01). The angulated group revealed 22.45 % more straightening than the non-angulated group. Recoil of the Endurant device occurred in the angulated group. No statistically significant intergroup differences were observed in any endoleaks, complications, or re-intervention rates (p > 0.05). Pre-EVAR angle was the only predictor for post-procedural angle change (p < 0.001).ConclusionEVAR is applicable for patients with highly angulated aneurysm neck and provides consistent neck straightening over long-term follow-up. Recoil was evident in the angulated group using the Endurant device.

Giant left coronary ostial aneurysm after modified Bentall procedure in a Marfan patient.

Science.gov (United States)

Okamoto, Kazuma; Casselman, Filip P; De Geest, Raphael; Vanermen, Hugo

2008-12-01

We performed surgical repair of a giant left coronary ostial aneurysm after aortic root replacement using composite valve graft (modified Bentall procedure) in a patient with Marfan syndrome. Aneurysmal formation in the left main stem itself is very rare. In order to avoid mobilizing the coronary ostium from severe adhesions after previous surgery and to reduce the tension on the anastomosis, the left main trunk was reconstructed using an interposition Dacron graft. In aortic root surgeries in Marfan patients, the size of the side hole on the composite graft should be kept relatively small to fit the diameter of the native coronary arteries for prevention of coronary buttons from forming aneurysms at the level of the coronary button anastomosis. In addition, close observation to the coronary button anastomosis is indispensable in postoperative check-up.

Development of an organ-specific insert phantom generated using a 3D printer for investigations of cardiac computed tomography protocols.

Science.gov (United States)

Abdullah, Kamarul A; McEntee, Mark F; Reed, Warren; Kench, Peter L

2018-04-30

An ideal organ-specific insert phantom should be able to simulate the anatomical features with appropriate appearances in the resultant computed tomography (CT) images. This study investigated a 3D printing technology to develop a novel and cost-effective cardiac insert phantom derived from volumetric CT image datasets of anthropomorphic chest phantom. Cardiac insert volumes were segmented from CT image datasets, derived from an anthropomorphic chest phantom of Lungman N-01 (Kyoto Kagaku, Japan). These segmented datasets were converted to a virtual 3D-isosurface of heart-shaped shell, while two other removable inserts were included using computer-aided design (CAD) software program. This newly designed cardiac insert phantom was later printed by using a fused deposition modelling (FDM) process via a Creatbot DM Plus 3D printer. Then, several selected filling materials, such as contrast media, oil, water and jelly, were loaded into designated spaces in the 3D-printed phantom. The 3D-printed cardiac insert phantom was positioned within the anthropomorphic chest phantom and 30 repeated CT acquisitions performed using a multi-detector scanner at 120-kVp tube potential. Attenuation (Hounsfield Unit, HU) values were measured and compared to the image datasets of real-patient and Catphan ® 500 phantom. The output of the 3D-printed cardiac insert phantom was a solid acrylic plastic material, which was strong, light in weight and cost-effective. HU values of the filling materials were comparable to the image datasets of real-patient and Catphan ® 500 phantom. A novel and cost-effective cardiac insert phantom for anthropomorphic chest phantom was developed using volumetric CT image datasets with a 3D printer. Hence, this suggested the printing methodology could be applied to generate other phantoms for CT imaging studies. © 2018 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical

Importance of initial stress for abdominal aortic aneurysm wall motion: Dynamic MRI validated finite element analysis

NARCIS (Netherlands)

Merkx, M.A.G.; Veer, van 't M.; Speelman, L.; Breeuwer, M.; Buth, J.; Vosse, van de F.N.

2009-01-01

Currently the transverse diameter is the primary decision criterion to assess rupture risk in patients with an abdominal aortic aneurysm (AAA). To obtain a measure for more patient-specific risk assessment, aneurysm wall stress, calculated using finite element analysis (FEA), has been evaluated in

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

Science.gov (United States)

Lv, Nan; Wang, Chi; Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

2016-01-01

The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms. While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p PCoA aneurysms.

Flow stagnation volume and abdominal aortic aneurysm growth: Insights from patient-specific computational flow dynamics of Lagrangian-coherent structures.

Science.gov (United States)

Joly, Florian; Soulez, Gilles; Garcia, Damien; Lessard, Simon; Kauffmann, Claude

2018-01-01

Abdominal aortic aneurysms (AAA) are localized, commonly-occurring dilations of the aorta. When equilibrium between blood pressure (loading) and wall mechanical resistance is lost, rupture ensues, and patient death follows, if not treated immediately. Experimental and numerical analyses of flow patterns in arteries show direct correlations between wall shear stress and wall mechano-adaptation with the development of zones prone to thrombus formation. For further insights into AAA flow topology/growth interaction, a workout of patient-specific computational flow dynamics (CFD) is proposed to compute finite-time Lyapunov exponents and extract Lagrangian-coherent structures (LCS). This computational model was first compared with 4-D phase-contrast magnetic resonance imaging (MRI) in 5 patients. To better understand the impact of flow topology and transport on AAA growth, hyperbolic, repelling LCS were computed in 1 patient during 8-year follow-up, including 9 volumetric morphologic AAA measures by computed tomography-angiography (CTA). LCS defined barriers to Lagrangian jet cores entering AAA. Domains enclosed between LCS and the aortic wall were considered to be stagnation zones. Their evolution was studied during AAA growth. Good correlation - 2-D cross-correlation coefficients of 0.65, 0.86 and 0.082 (min, max, SD) - was obtained between numerical simulations and 4-D MRI acquisitions in 6 specific cross-sections from 4 patients. In follow-up study, LCS divided AAA lumens into 3 dynamically-isolated zones: 2 stagnation volumes lying in dilated portions of the AAA, and circulating volume connecting the inlet to the outlet. The volume of each zone was tracked over time. Although circulating volume remained unchanged during 8-year follow-up, the AAA lumen and main stagnation zones grew significantly (8 cm 3 /year and 6 cm 3 /year, respectively). This study reveals that transient transport topology can be quantified in patient-specific AAA during disease progression

Conventional and cine-MRI in patients with aneurysms of the abdominal aorta

International Nuclear Information System (INIS)

Gross-Fengels, W.; Friedmann, G.; Lemaitre, F.; Schmidt, R.; Lanfermann, H.; Erasmi, H.; Koeln Univ.

1991-01-01

We studied 40 patients with aneurysms of the abdominal aorta by MRI. These results were compared with those obtained by real-time sonography (n = 40), angiography (n = 32) and CT (n = 16). In 30 patients the imaging results were compared - as far as possible - with the operative findings. MRI proved more reliable, especially if compared with sonography, in evaluating renal or iliac artery involvement. Mural thrombi were detected more often (93%) by MRI than by CT (85%) or sonography (83%). Cine-MRI showed strong turbulences in 33%. Turbulences did not correlate with the size of the aneurysm. (orig.) [de

Stent-assisted coiling of intracranial aneurysms using LEO stents: long-term follow-up in 153 patients.

Science.gov (United States)

Sedat, Jacques; Chau, Yves; Gaudart, Jean; Sachet, Marina; Beuil, Stephanie; Lonjon, Michel

2018-02-01

Coiling associated with placement of a self-expandable intracranial stent has improved the treatment of intracranial wide-necked aneurysms. Little is known, however, about the durability of this treatment. The purpose of this report is to present our experience with the LEO stent and to evaluate the complications, effectiveness, and long-term results of this technique. We analyzed the records of 155 intracranial unruptured aneurysms that were treated by stent-assisted coiling with a LEO stent between 2008 and 2012. Procedural, early post-procedural, and delayed complications were recorded. Clinical and angiographic follow-up of patients was conducted over a period of at least 36 months. No procedural mortality was observed. One-month morbidity was observed in 14 out of 153 patients (9,15%). One hundred thirty-eight patients (with 140 aneurysms) had clinical and angiographic follow-up for more than 36 months. No aneurysm rupture was observed during follow-up. Four patients presented an intra-stent stenosis at 8 months, and 6 patients who had an early recurrence were retreated. Final results showed 85% complete occlusion, 13% neck remnants, and 2% stable incomplete occlusion. Stent-assisted coiling with the LEO stent is a safe and effective treatment for unruptured intracranial aneurysms. The long-term clinical outcomes with the LEO stent are excellent with a high rate of complete occlusion that is stable over time.

[Myocardial infarction (NSTEMI) in a young patient with coronary aneurysm].

Science.gov (United States)

Kulzer, M J; Mooyaart, E A Q; Hetterich, H

2012-04-01

A 28-year-old man without a significant past medical history presented to our emergency department with severe chest pain and dyspnoa. Vital signs and the rest of the physical examination were unremarkable. The electrocardiogram showed T-wave inversions and the cardiac enzymes were elevated. Angiocardiography showed an aneurysm of the right coronary artery and a thrombus formation in its distal part. Intracoronary thrombolytic therapy was attempted an oral anticoagulation was started. Further investigations did not find the cause of the aneurysmatic RCA. The patient had no further episode of chest pain. Acute coronary syndrome is a rare finding in patients under the age of 30 years. Coronary aneurysms with associated thrombus can be the cause of it. © Georg Thieme Verlag KG Stuttgart · New York.

Does Lower Limb Exercise Worsen Renal Artery Hemodynamics in Patients with Abdominal Aortic Aneurysm?

OpenAIRE

Sun, Anqiang; Tian, Xiaopeng; Zhang, Nan; Xu, Zaipin; Deng, Xiaoyan; Liu, Ming; Liu, Xiao

2015-01-01

Renal artery stenosis (RAS) and renal complications emerge in some patients after endovascular aneurysm repair (EVAR) to treat abdominal aorta aneurysm (AAA). The mechanisms for the causes of these problems are not clear. We hypothesized that for EVAR patients, lower limb exercise could negatively influence the physiology of the renal artery and the renal function, by decreasing the blood flow velocity and changing the hemodynamics in the renal arteries. To evaluate this hypothesis, pre- and ...

Poster — Thur Eve — 71: A 4D Multimodal Lung Phantom for Regmentation Evaluation

International Nuclear Information System (INIS)

Markel, D; Levesque, I R; El Naqa, I

2014-01-01

Segmentation and registration of medical imaging data are two processes that can be integrated (a process termed regmentation) to iteratively reinforce each other, potentially improving efficiency and overall accuracy. A significant challenge is presented when attempting to validate the joint process particularly with regards to minimizing geometric uncertainties associated with the ground truth while maintaining anatomical realism. This work demonstrates a 4D MRI, PET, and CT compatible tissue phantom with a known ground truth for evaluating registration and segmentation accuracy. The phantom consists of a preserved swine lung connected to an air pump via a PVC tube for inflation. Mock tumors were constructed from sea sponges contained within two vacuum-sealed compartments with catheters running into each one for injection of radiotracer solution. The phantom was scanned using a GE Discovery-ST PET/CT scanner and a 0.23T Phillips MRI, and resulted in anatomically realistic images. A bifurcation tracking algorithm was implemented to provide a ground truth for evaluating registration accuracy. This algorithm was validated using known deformations of up to 7.8 cm using a separate CT scan of a human thorax. Using the known deformation vectors to compare against, 76 bifurcation points were selected. The tracking accuracy was found to have maximum mean errors of −0.94, 0.79 and −0.57 voxels in the left-right, anterior-posterior and inferior-superior directions, respectively. A pneumatic control system is under development to match the respiratory profile of the lungs to a breathing trace from an individual patient

Use of modified Sandwich-graft technique to preserve hypogastric artery in EVAR treatment of complex aortic aneurysm anatomy.

Science.gov (United States)

Mosquera Arochena, N; Rodríguez Feijoo, G; Carballo Fernandez, C; Molina Herrero, F; Fernandez Lebrato, R; Barrios Castro, A; Garcia Fernandez, I

2011-10-01

Since the introduction of the first endoprosthetic devices, continuous development in techniques and implants has occurred, such as the introduction of a stent graft with branches designed to preserve antegrade flow in the hypogastric artery, a stent-graft designed to treat extreme neck angulation and iliac tortuosity, as well as "Sandwich" and "Chimney" techniques used to maintain perfusion in branch vessels originating in the region to be treated. This paper describes how the Sandwich-Graft technique was adapted, as described by Lobato et al., employing the Aorfix™ system (Lombard Medical) and the Viabahn™ (W.L.Gore) to preserve hypogastric flow in cases with extreme neck angulation and iliac tortuosity. The study included four patients treated from April 2010 until November 2010 with the modified Sandwich technique. All patients eligible for this approach were considered unfit for open repair and were not suitable for an iliac branch graft (Z-BIS Zenith™ Cook Medical). A bifurcated endograft was implanted with specific, in-situ, branching to the target hypogastric artery and achieved clinical and technical success, in all the patients. After a 11-month follow-up in two cases and a six-month follow-up in the other two, clinical results were successful. All patients were endoleak-free, had patent hypogastric branches and had shrinking or stable aneurysms. The initial experience shows that the Sandwich technique with the Aorfix™ stent-graft demonstrated to be effective in endovascular repair of abdominal aortic aneurysms in patients with aortoiliac anatomy hostile to preserving hypogastric artery patency. This graft allows a broader group of patients to be treated with endovascular repair without potential complications of hypogastric artery occlusion; however, further studies are needed to evaluate long-term results in larger numbers of patients.

Detection and evaluation of intracranial aneurysms with 16-row multislice CT angiography

International Nuclear Information System (INIS)

Tipper, G.; U-King-Im, J.M.; Price, S.J.; Trivedi, R.A.; Cross, J.J.; Higgins, N.J.; Farmer, R.; Wat, J.; Kirollos, R.; Kirkpatrick, P.J.; Antoun, N.M.; Gillard, J.H.

2005-01-01

AIM: The aim of this study was to assess the usefulness of 16-row multislice CT angiography (CTA) in evaluating intracranial aneurysms, by comparison with conventional digital subtraction angiography (DSA) and intraoperative findings. METHODS: A consecutive series of 57 patients, scheduled for DSA for suspected intracranial aneurysm, was prospectively recruited to have CTA. This was performed with a 16-detector row machine, detector interval 0.75 mm, 0.5 rotation/s, table speed 10 mm/rotation and reconstruction interval 0.40 mm. CTA studies were independently and randomly assessed by two neuroradiologists and a vascular neurosurgeon blinded to the DSA and surgical findings. Review of CTA was performed on workstations with an interactive 3D volume-rendered algorithm. RESULTS: DSA or intraoperative findings or both confirmed 53 aneurysms in 44 patients. For both independent readers, sensitivity and specificity per aneurysm of DSA were 96.2% and 100%, respectively. Sensitivity and specificity of CTA were also 96.2% and 100%, respectively. Mean diameter of aneurysms was 6.3 mm (range 1.9 to 28.1 mm, SD 5.2 mm). For aneurysms of less than 3 mm, CTA had a sensitivity of 91.7% for each reader. Although the neurosurgeon would have been happy to proceed to surgery on the basis of CTA alone in all cases, he judged that DSA might have provided helpful additional anatomical information in 5 patients. CONCLUSION: The diagnostic accuracy of 16-slice CTA is promising and appears equivalent to that of DSA for detection and evaluation of intracranial aneurysms. A strategy of using CTA as the primary imaging method, with DSA reserved for cases of uncertainty, appears to be practical and safe

Aneurysmal wall enhancement and perianeurysmal edema after endovascular treatment of unruptured cerebral aneurysms

International Nuclear Information System (INIS)

Su, I. Chang; Willinsky, Robert A.; Agid, Ronit; Fanning, Noel F.

2014-01-01

Perianeurysmal edema and aneurysm wall enhancement are previously described phenomenon after coil embolization attributed to inflammatory reaction. We aimed to demonstrate the prevalence and natural course of these phenomena in unruptured aneurysms after endovascular treatment and to identify factors that contributed to their development. We performed a retrospective analysis of consecutively treated unruptured aneurysms between January 2000 and December 2011. The presence and evolution of wall enhancement and perianeurysmal edema on MRI after endovascular treatment were analyzed. Variable factors were compared among aneurysms with and without edema. One hundred thirty-two unruptured aneurysms in 124 patients underwent endovascular treatment. Eighty-five (64.4 %) aneurysms had wall enhancement, and 9 (6.8 %) aneurysms had perianeurysmal brain edema. Wall enhancement tends to persist for years with two patterns identified. Larger aneurysms and brain-embedded aneurysms were significantly associated with wall enhancement. In all edema cases, the aneurysms were embedded within the brain and had wall enhancement. Progressive thickening of wall enhancement was significantly associated with edema. Edema can be symptomatic when in eloquent brain and stabilizes or resolves over the years. Our study demonstrates the prevalence and some appreciation of the natural history of aneurysmal wall enhancement and perianeurysmal brain edema following endovascular treatment of unruptured aneurysms. Aneurysmal wall enhancement is a common phenomenon while perianeurysmal edema is rare. These phenomena are likely related to the presence of inflammatory reaction near the aneurysmal wall. Both phenomena are usually asymptomatic and self-limited, and prophylactic treatment is not recommended. (orig.)

Noninvasive follow-up of GDC-treated saccular aneurysms by MR angiography

International Nuclear Information System (INIS)

Weber, W.; Henkes, H.; Nahser, H.C.; Roer, N.; Kuehne, D.; Yousry, T.A.; Felber, S.R.

2001-01-01

The aim of this study was to determine sensitivity and specificity of magnetic resonance angiography (MRA) for the assessment of durable occlusion of intracranial aneurysms with Guglielmi detachable coils (GDC) and to point out the influence of MRA results in re-intervention strategies. Forty-five patients with 54 aneurysms that were previously treated by endovascular occlusion with GDC were selected for this study. All patients underwent digital subtraction angiography (DSA) and MRA examinations on the same day. The time-of-flight MRA studies were performed on a 1-T scanner. The MRA images were first read by radiologists who were not aware of the DSA results. In a second consensus reading by the neuroradiologists who had performed all interventional procedures of this series, the decision was made as to whether re-treatment was necessary. The distribution of aneurysm sizes, configurations and treatment results were sufficient for an unbiased evaluation. The first blinded evaluation revealed a sensitivity of 71% and a specificity of 95% for MRA assessment of aneurysm reperfusion. In the second consensus reading, the sensitivity increased to 92% and the specificity was 98%. The blinded reading indicates that MRA is a useful adjunct to DSA for the assessment of durable results after endovascular treatment of intracranial aneurysms. In the consensus reading it became obvious that sensitivity and specificity of MRA can be increased to 92 and 98%, respectively, if the results were evaluated by experienced neuroradiologists, including prior knowledge of all other examinations. We have already increased the follow-up intervals for DSA and use MRA intermittently, based on these results. (orig.)

Sensitivity and specifity of different imaging methods for the detection of cerebral aneurysms; Sensitivitaet und Spezifitaet bildgebender Verfahren fuer den Nachweis intrakranieller Aneurysmen

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Ringelstein, Adrian; Forsting, Michael [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie

2015-09-15

The prevalence or cerebral aneurysms is estimated at 2 %. Out of these aciniform aneurysm, 0,1 % rupture each year. The 30-day-mortality after a subarachnoid hemorrhage (SAH) is estimated at 45 %. Additionally, about 50 % of the patients suffer from severe persistent neurologic deficits. The most reliable way to prevent rupture is early detection and prophylactic therapy of an unruptured aneurysm. For this, knowledge of the different imaging methods currently available and their diagnostic potential is highly desirable. This review describes the potential of CT, MRI and catheter angiography in diagnosing cerebral aneurysms, as well as therapy planning and follow-up care of patients. Based on this, some recommendations are made for management of patients with SAH.

Electronic database of arterial aneurysms

Directory of Open Access Journals (Sweden)

Fabiano Luiz Erzinger

2014-12-01

Full Text Available Background:The creation of an electronic database facilitates the storage of information, as well as streamlines the exchange of data, making easier the exchange of knowledge for future research.Objective:To construct an electronic database containing comprehensive and up-to-date clinical and surgical data on the most common arterial aneurysms, to help advance scientific research.Methods:The most important specialist textbooks and articles found in journals and on internet databases were reviewed in order to define the basic structure of the protocol. Data were computerized using the SINPE© system for integrated electronic protocols and tested in a pilot study.Results:The data entered onto the system was first used to create a Master protocol, organized into a structure of top-level directories covering a large proportion of the content on vascular diseases as follows: patient history; physical examination; supplementary tests and examinations; diagnosis; treatment; and clinical course. By selecting items from the Master protocol, Specific protocols were then created for the 22 arterial sites most often involved by aneurysms. The program provides a method for collection of data on patients including clinical characteristics (patient history and physical examination, supplementary tests and examinations, treatments received and follow-up care after treatment. Any information of interest on these patients that is contained in the protocol can then be used to query the database and select data for studies.Conclusions:It proved possible to construct a database of clinical and surgical data on the arterial aneurysms of greatest interest and, by adapting the data to specific software, the database was integrated into the SINPE© system, thereby providing a standardized method for collection of data on these patients and tools for retrieving this information in an organized manner for use in scientific studies.

Hepatic artery aneurysms (HAAs)

International Nuclear Information System (INIS)

Nosratini, H.

2004-01-01

The hepatic artery aneurysms are rare, especially in interahepatic branches, The frequency consists of 75-80% extrahepatic and 20-25% intrahepatic. Catheterization is achieved usually from common femoral artery, other methods implemented in the case of unsuccessful catheterization from femoral artery, are translumbar and brachial catheterization. The study consist of 565 patients that were referred to the angiography ward, During seven years of assessment, five cases of hepatic artery aneurysm were found; this is a rare condition reported in the English literature. In the literature as well as in this case report the hepatic artery aneurysms are rare. In reported series the extrahepatic artery aneurysms are found more often than in the intrahepatic artery aneurysm but in this case report intrahepatic artery aneurysms are more than extrahepatic one. (author)

The Effects of Metal on Size Specific Dose Estimation (SSDE) in CT: A Phantom Study

Science.gov (United States)

Alsanea, Maram M.

Over the past number of years there has been a significant increase in the awareness of radiation dose from use of computed tomography (CT). Efforts have been made to reduce radiation dose from CT and to better quantify dose being delivered. However, unfortunately, these dose metrics such as CTDI vol are not a specific patient dose. In 2011, the size-specific dose estimation (SSDE) was introduced by AAPM TG-204 which accounts for the physical size of the patient. However, the approach presented in TG-204 ignores the importance of the attenuation differences in the body. In 2014, a newer methodology that accounted for tissue attenuation was introduced by the AAPM TG-220 based on the concept of water equivalent diameter, Dw. One of the limitation of TG-220 is that there is no estimation of the dose while highly attenuating objects such as metal is present in the body. The purpose of this research is to evaluate the accuracy of size-specific dose estimates in CT in the presence of simulated metal prostheses using a conventional PMMA CTDI phantom at different phantom diameter (body and head) and beam energy. Titanium, Cobalt- chromium and stainless steel alloys rods were used in the study. Two approaches were used as introduced by AAPM TG-204 and 220 utilizing the effective diameter and the Dw calculations. From these calculations, conversion factors have been derived that could be applied to the measured CTDIvol to convert it to specific patient dose, or size specific dose estimate, (SSDE). Radiation dose in tissue (f-factor = 0.94) was measured at various chamber positions with the presence of metal. Following, an average weighted tissue dose (AWTD) was calculated in a manner similar to the weighted CTDI (CTDIw). In general, for the 32 cm body phantom SSDE220 provided more accurate estimates of AWTD than did SSDE204. For smaller patient size, represented by the 16 cm head phantom, the SSDE204 was a more accurate estimate of AWTD that that of SSDE220. However, as the

Aneurysm-Specific miR-221 and miR-146a Participates in Human Thoracic and Abdominal Aortic Aneurysms

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Premakumari Venkatesh

2017-04-01

Full Text Available Altered microRNA expression is implicated in cardiovascular diseases. Our objective was to determine microRNA signatures in thoracic aortic aneurysms (TAAs and abdominal aortic aneurysms (AAAs compared with control non-aneurysmal aortic specimens. We evaluated the expression of fifteen selected microRNA in human TAA and AAA operative specimens compared to controls. We observed significant upregulation of miR-221 and downregulation of miR-1 and -133 in TAA specimens. In contrast, upregulation of miR-146a and downregulation of miR-145 and -331-3p were found only for AAA specimens. Upregulation of miR-126 and -486-5p and downregulation of miR-30c-2*, -155, and -204 were observed in specimens of TAAs and AAAs. The data reveal microRNA expression signatures unique to aneurysm location and common to both thoracic and abdominal pathologies. Thus, changes in miR-1, -29a, -133a, and -221 are involved in TAAs and miR-145, -146, and -331-3p impact AAAs. This work validates prior studies on microRNA expression in aneurysmal diseases.

Endovascular treatment of posterior cerebral artery aneurysms using detachable coils

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Roh, Hong Gee [Kangwon National University Hospital, Department of Radiology, Chuncheon, Kangwon-do (Korea); Konkuk University Hospital, Department of Radiology, Seoul (Korea); Kim, Sam Soo; Han, Heon [Kangwon National University Hospital, Department of Radiology, Chuncheon, Kangwon-do (Korea); Kang, Hyun-Seung [Konkuk University Hospital, Department of Neurosurgery, Seoul (Korea); Moon, Won-Jin [Konkuk University Hospital, Department of Radiology, Seoul (Korea); Byun, Hong Sik [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea)

2008-03-15

Aneurysms of the posterior cerebral artery (PCA) are rare, and most of the studies reported in the literature in which the endovascular approach was applied were carried out on a limited number of patients with PCA aneurysms. We retrospectively reviewed our cases of PCA aneurysms - at various locations and of differing shapes - that received endovascular treatment and evaluated the treatment outcome. From January 1996 to December 2006, 13 patients (eight females and five males) with 17 PCA aneurysms (nine fusiform and eight saccular) were treated using the endovascular approach. The age of the patients ranged from 20 to 67 years, with a mean age of 44 years. Of the 13 patients, ten presented with intracranial hemorrhage, and one patient, with a large P2 aneurysm, presented with trigeminal neuralgia; the aneurysms were asymptomatic in the remaining two patients. All 13 patients were successfully treated, with only one procedure-related symptomatic complication. Seven patients were treated by occlusion of the aneurysm and parent artery together; five patients, by selective embolization of the aneurysm; one patient, by partial coiling. Although infarctions were found in two patients treated with selective embolization and in three patients treated with parent artery occlusion, only one patient with a ruptured P2 aneurysm treated with parent artery occlusion developed transient amnesia as an ischemic symptom. Posterior cerebral artery aneurysms can be treated safely with either occlusion of the aneurysm together with the PCA or with a selective coil embolization. Infarctions may occur after endovascular treatment, but they are rarely the cause of a disabling symptom. (orig.)

Perceptions of phantom rectum syndrome and health-related quality of life in patients following abdominoperineal resection for rectal cancer.

Science.gov (United States)

Fingren, Jeanette; Lindholm, Elisabet; Carlsson, Eva

2013-01-01

The aim of the study was to investigate how patients described their perceptions of phantom rectum syndrome after abdominoperineal resection and ostomy creation, and its influence on daily living and health-related quality of life. A further aim was to find out strategies patients use to alleviate phantom rectum syndrome sensations. Twenty-five patients who underwent abdominoperineal resection and a colostomy (18 men and 7 women; median age 5 63 years; range, 40-78 years) at Sahlgrenska University Hospital, Göteborg, Sweden, participated in the study. At follow-up 8 months postsurgery, a WOC nurse interviewed patients with a structured questionnaire about the experience of nonpainful and painful sensations in the perineal area. Health-related quality of life was evaluated using a general cancer-specific instrument (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire version 3.0). Twenty-four patients (96%) experienced painful or nonpainful phantom rectum syndrome at some point during the first 8 postoperative months. The nonpainful sensations (20 patients) occurred in connection with emptying of feces via the stoma, when performing colostomy irrigation, at rest, or in various positions. Fifteen patients experienced painful sensations, characterized as pins and needles, pain in the perineal area, stinging, and burning occurring mostly in sitting positions. Patients with painful sensations had statistically significant higher scores regarding pain and lower scores for social function than those without painful sensations (P < .031). Phantom rectum symptoms caused worries and concerns and influenced daily life in 29% (n = 5). Phantom rectum syndrome is prevalent in patients undergoing abdominoperineal resection and ostomy creation. Information about phantom rectum syndrome should be shared preoperatively and during follow-up in order to promote optimal quality of life and alleviate bothersome symptoms and concerns associated with

Prognosis of patients in coma after acute subdural hematoma due to ruptured intracranial aneurysm.

Science.gov (United States)

Torné, Ramon; Rodríguez-Hernández, Ana; Romero-Chala, Fabián; Arikan, Fuat; Vilalta, Jordi; Sahuquillo, Juan

2016-04-01

Acute subdural hematomas (aSDH) secondary to intracranial aneurysm rupture are rare. Most patients present with coma and their functional prognosis has been classically considered to be very poor. Previous studies mixed good-grade and poor-grade patients and reported variable outcomes. We reviewed our experience by focusing on patients in coma only and hypothesized that aSDH might worsen initial mortality but not long-term functional outcome. Between 2005 and 2013, 440 subarachnoid hemorrhage (SAH) patients were admitted to our center. Nineteen (4.3%) were found to have an associated aSDH and 13 (2.9%) of these presented with coma. Their prospectively collected clinical and outcome data were reviewed and compared with that of 104 SAH patients without aSDH who presented with coma during the same period. Median aSDH thickness was 10mm. Four patients presented with an associated aneurysmal cortical laceration and only one had good recovery. Overall, we observed good long-term outcomes in both SAH patients in coma with aSDH and those without aSDH (38.5% versus 26.4%). Associated aSDH does not appear to indicate a poorer long-term functional prognosis in SAH patients presenting with coma. Anisocoria and brain herniation are observed in patients with aSDH thicknesses that are smaller than those observed in trauma patients. Despite a high initial mortality, early surgery to remove the aSDH results in a good outcome in over 60% of survivors. Aneurysmal cortical laceration appears to be an independent entity which shows a poorer prognosis than other types of aneurysmal aSDH. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mycotic Aneurysm of the Aortic Arch

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Ji Hye Seo

2014-08-01

Full Text Available A mycotic aneurysm of the thoracic aorta is rare. We report a case of mycotic aneurysm that developed in the aortic arch. An 86-year-old man was admitted with fever and general weakness. Blood culture yielded methicillin-resistant Staphylococcus aureus. Chest X-ray showed an enlarged aortic arch, and computed tomography scan revealed an aneurysm in the aortic arch. The patient was treated only with antibiotics and not surgically. The size of the aneurysm increased rapidly, resulting in bronchial obstruction and superimposed pneumonia. The patient died of respiratory failure.

Technique to Avoid Hemodialysis Catheter in Patients with Failing Aneurysmal Arteriovenous Fistula by Creating a Concomitant New Arteriovenous Fistula.

Science.gov (United States)

Lara, Kelly A; Chua, Rochelle Anne; Vo, Trung D

2018-05-01

Autogenous arteriovenous fistula (AVF) is the primary recommended access for hemodialysis. Long-term use will not uncommonly result in AVF aneurysmal degeneration. Aneurysm-associated complications encompass pain, skin ulceration, infection, thrombosis, cannulation difficulties, and life-threatening bleeding. Various methods to repair aneurysmal AVFs have been described. However, there may be circumstances when this is not possible and require insertion of a temporary hemodialysis catheter (HDC) until a new arteriovenous access is created. We describe a case series of creating a new simultaneous AVF while continuing to use the primary failing aneurysmal AVF to avoid placement of an HDC. Once the new AVF becomes operational, the primary aneurysmal AVF can be abandoned. Six patients underwent simultaneous new AVF creation, 4 ipsilateral, and 2 contralateral. None of the patients developed symptomatic steal syndrome or congestive heart failure. Five of 6 patients had successful usage of the new AVF, and subsequently underwent ligation and excision of the aneurysmal AVF, thus avoiding a temporary HDC. Close monitoring for skin compromise and bleeding in the aneurysmal AVF is recommended while the new AVF matures. Copyright © 2018 Elsevier Inc. All rights reserved.

Neonatal Intracranial Aneurysm Rupture Treated by Endovascular Management: A Case Report

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Yi-Pei Tai

2010-08-01

Full Text Available Pediatric intracranial aneurysm rupture is rare, and is traditionally managed by surgical clipping. To the best of our knowledge, endovascular embolization of aneurysms in neonates has not previously been reported in Taiwan. We report a 9-day-old boy with intracranial aneurysms who underwent endovascular embolization, representing the youngest reported case in Taiwan. The 9-day-old boy presented with non-specific symptoms of irritable crying, seizure and respiratory distress. Computed tomography disclosed intraventricular hemorrhage, subarachnoid hemorrhage and focal intracranial hemorrhage around the right cerebellum. Subsequent computed tomographic angiography showed two sequential fusiform aneurysms, measuring 3 mm, located in the right side posterior inferior cerebellar artery (PICA. The patient underwent endovascular embolization because of the high risk of aneurysm re-rupture and the impossibility of surgical clipping due to the fusiform nature of the aneurysms. A postembolization angiogram revealed complete obliteration of the right distal PICA and proximal aneurysm. The distal PICA aneurysm was revascularized from the collateral circulation, but demonstrated a slow and delayed filling pattern. The patient's condition remained stable over the following week, and he was discharged without anticonvulsant therapy. No significant developmental delay was noted at follow-up at when he was 3 months old. This case emphasizes the need for clinical practitioners to consider a diagnosis of intracranial hemorrhage in neonates with seizure and increased intracranial pressure. Neonatal intracranial aneurysms can be treated safely by endovascular treatment.

Calculating when elective abdominal aortic aneurysm repair improves survival for individual patients: development of the Aneurysm Repair Decision Aid and economic evaluation.

Science.gov (United States)

Grant, Stuart W; Sperrin, Matthew; Carlson, Eric; Chinai, Natasha; Ntais, Dionysios; Hamilton, Matthew; Dunn, Graham; Buchan, Iain; Davies, Linda; McCollum, Charles N

2015-04-01

Abdominal aortic aneurysm (AAA) repair aims to prevent premature death from AAA rupture. Elective repair is currently recommended when AAA diameter reaches 5.5 cm (men) and 5.0 cm (women). Applying population-based indications may not be appropriate for individual patient decisions, as the optimal indication is likely to differ between patients based on age and comorbidities. To develop an Aneurysm Repair Decision Aid (ARDA) to indicate when elective AAA repair optimises survival for individual patients and to assess the cost-effectiveness and associated uncertainty of elective repair at the aneurysm diameter recommended by the ARDA compared with current practice. The UK Vascular Governance North West and National Vascular Database provided individual patient data to develop predictive models for perioperative mortality and survival. Data from published literature were used to model AAA growth and risk of rupture. The cost-effectiveness analysis used data from published literature and from local and national databases. A combination of systematic review methods and clinical registries were used to provide data to populate models and inform the structure of the ARDA. Discrete event simulation (DES) was used to model the patient journey from diagnosis to death and synthesised data were used to estimate patient outcomes and costs for elective repair at alternative aneurysm diameters. Eight patient clinical scenarios (vignettes) were used as exemplars. The DES structure was validated by clinical and statistical experts. The economic evaluation estimated costs, quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) from the NHS, social care provider and patient perspective over a lifetime horizon. Cost-effectiveness acceptability analyses and probabilistic sensitivity analyses explored uncertainty in the data and the value for money of ARDA-based decisions. The ARDA outcome measures include perioperative mortality risk, annual risk of

Fluid, solid and fluid-structure interaction simulations on patient-based abdominal aortic aneurysm models.

Science.gov (United States)

Kelly, Sinead; O'Rourke, Malachy

2012-04-01

This article describes the use of fluid, solid and fluid-structure interaction simulations on three patient-based abdominal aortic aneurysm geometries. All simulations were carried out using OpenFOAM, which uses the finite volume method to solve both fluid and solid equations. Initially a fluid-only simulation was carried out on a single patient-based geometry and results from this simulation were compared with experimental results. There was good qualitative and quantitative agreement between the experimental and numerical results, suggesting that OpenFOAM is capable of predicting the main features of unsteady flow through a complex patient-based abdominal aortic aneurysm geometry. The intraluminal thrombus and arterial wall were then included, and solid stress and fluid-structure interaction simulations were performed on this, and two other patient-based abdominal aortic aneurysm geometries. It was found that the solid stress simulations resulted in an under-estimation of the maximum stress by up to 5.9% when compared with the fluid-structure interaction simulations. In the fluid-structure interaction simulations, flow induced pressure within the aneurysm was found to be up to 4.8% higher than the value of peak systolic pressure imposed in the solid stress simulations, which is likely to be the cause of the variation in the stress results. In comparing the results from the initial fluid-only simulation with results from the fluid-structure interaction simulation on the same patient, it was found that wall shear stress values varied by up to 35% between the two simulation methods. It was concluded that solid stress simulations are adequate to predict the maximum stress in an aneurysm wall, while fluid-structure interaction simulations should be performed if accurate prediction of the fluid wall shear stress is necessary. Therefore, the decision to perform fluid-structure interaction simulations should be based on the particular variables of interest in a given

Post procedure headache in patients treated for neurovascular arteriovenous malformations and aneurysms using endovascular therapy

DEFF Research Database (Denmark)

Khan, Sabrina; Amin, Faisal Mohammad; Hauerberg, John

2016-01-01

BACKGROUND: Though endovascular therapy (EVT) is increasingly applied in the treatment of intracranial vascular lesions, little is known about the effect of EVT on post-procedure headache. We aimed to investigate the prevalence of headache in patients who have undergone EVT for cerebral...... arteriovenous malformations (AVMs) and aneurysms. METHODS: A total of 324 patients underwent EVT treatment for aneurysms and AVMs at the Danish National Hospital from January 2012 to December 2014. We applied strict exclusion criteria in order to minimize the effect of other factors on headache occurrence, e.......g., craniotomy. Eligible subjects were phone-interviewed using a purpose-developed semi-structured questionnaire. Headaches were classified according to ICHD-III beta criteria. RESULTS: The 59 patients underwent treatment of aneurysms (n = 43), cranial dural fistulas (n = 11), and AVMs (n = 5...

GDC 360 for the endovascular treatment of intracranial aneurysms: a matched-pair study analysing angiographic outcomes with GDC 3D coils in 38 patients

International Nuclear Information System (INIS)

Taschner, Christian A.; Thines, Laurent; Lejeune, Jean-Paul; El-Mahdy, Mohamed; Rachdi, Henda; Gauvrit, Jean-Yves; Pruvo, Jean-Pierre; Leclerc, Xavier

2009-01-01

The purpose of this study was to determine whether coil embolisation with a new complex-shaped Guglielmi Detachable Coil (GDC 360 ; Boston Scientific Neurovascular, Fremont, CA, USA) has any effect on the stability of aneurysm occlusion. Fifty-one consecutive patients with intracranial aneurysms treated with GDC 360 were included. Angiographic results and adverse neurological events during the follow-up period were recorded. For 38 patients treated with GDC 360 with available follow-up data, a corresponding patient treated with GDC 3D was identified from our database. Matches were sought for rupture status, location, aneurysmal size, and neck size. The angiographic outcome of these matched controls at 6 months was compared to aneurysms treated with GDC 360 . Initial angiographic controls for 38 patients treated with GDC 360 showed complete occlusion in 32 aneurysms, and a neck remnant in six. At 6-month follow-up, complete occlusion was found in 29, a neck remnant in eight, and a residual aneurysm in one. One patient treated with GDC 360 needed retreatment for a major recanalisation. In 38 matched patients treated with GDC 3D, initial angiographic controls found complete aneurysmal occlusion in 30 aneurysms and a residual neck in 8. At 6-month follow-up, 24 aneurysms were completely occluded, ten showed a neck remnant, and residual aneurysms were seen in four. Four patients, treated with GDC 3D, were retreated for major aneurysm recanalisations. Our data suggests that endovascular coil embolisation with GDC 360 might improve long-term stability of coiled aneurysms when compared to GDC 3D. (orig.)

Level of headaches after surgical aneurysm clipping decreases significantly faster compared to endovascular coiled patients

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Athanasios K. Petridis

2017-04-01

Full Text Available In incidental aneurysms, endovascular treatment can lead to post-procedural headaches. We studied the difference of surgical clipping vs. endovascular coiling in concern to post-procedural headaches in patients with ruptured aneurysms. Sixtyseven patients with aneurysmal subarachnoidal haemorrhage were treated in our department from September 1st 2015 - September 1st 2016. 43 Patients were included in the study and the rest was excluded because of late recovery or highgrade subarachnoid bleedings. Twenty-two were surgical treated and twenty-one were interventionally treated. We compared the post-procedural headaches at the time points of 24 h, 21 days, and 3 months after treatment using the visual analog scale (VAS for pain. After surgical clipping the headache score decreased for 8.8 points in the VAS, whereas the endovascular treated population showed a decrease of headaches of 3.3 points. This difference was highly statistical significant and remained significant even after 3 weeks where the pain score for the surgically treated patients was 0.68 and for the endovascular treated 1.8. After 3 months the pain was less than 1 for both groups with surgically treated patients scoring 0.1 and endovascular treated patients 0.9 (not significant. Clipping is relieving the headaches of patients with aneurysm rupture faster and more effective than endovascular coiling. This effect stays significant for at least 3 weeks and plays a crucial role in stress relieve during the acute and subacute ICU care of such patients.

Bifurcations of non-smooth systems

Science.gov (United States)

Angulo, Fabiola; Olivar, Gerard; Osorio, Gustavo A.; Escobar, Carlos M.; Ferreira, Jocirei D.; Redondo, Johan M.

2012-12-01

Non-smooth systems (namely piecewise-smooth systems) have received much attention in the last decade. Many contributions in this area show that theory and applications (to electronic circuits, mechanical systems, …) are relevant to problems in science and engineering. Specially, new bifurcations have been reported in the literature, and this was the topic of this minisymposium. Thus both bifurcation theory and its applications were included. Several contributions from different fields show that non-smooth bifurcations are a hot topic in research. Thus in this paper the reader can find contributions from electronics, energy markets and population dynamics. Also, a carefully-written specific algebraic software tool is presented.

Sac Angiography and Glue Embolization in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysm

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Koike, Yuya, E-mail: r06118@hotmail.co.jp; Nishimura, Jun-ichi, E-mail: jun-ichi-n@nifty.com; Hase, Soichiro, E-mail: haseman@hotmail.co.jp; Yamasaki, Motoshige, E-mail: genyamasaki@gmail.com [Kawasaki Saiwai Hospital, Department of Interventional Radiology (Japan)

2015-04-15

PurposeThe purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients.MethodsA retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing.ResultsSac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images.ConclusionsEVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

Imaging and dosimetric errors in 4D PET/CT-guided radiotherapy from patient-specific respiratory patterns: a dynamic motion phantom end-to-end study.

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Bowen, S R; Nyflot, M J; Herrmann, C; Groh, C M; Meyer, J; Wollenweber, S D; Stearns, C W; Kinahan, P E; Sandison, G A

2015-05-07

Effective positron emission tomography / computed tomography (PET/CT) guidance in radiotherapy of lung cancer requires estimation and mitigation of errors due to respiratory motion. An end-to-end workflow was developed to measure patient-specific motion-induced uncertainties in imaging, treatment planning, and radiation delivery with respiratory motion phantoms and dosimeters. A custom torso phantom with inserts mimicking normal lung tissue and lung lesion was filled with [(18)F]FDG. The lung lesion insert was driven by six different patient-specific respiratory patterns or kept stationary. PET/CT images were acquired under motionless ground truth, tidal breathing motion-averaged (3D), and respiratory phase-correlated (4D) conditions. Target volumes were estimated by standardized uptake value (SUV) thresholds that accurately defined the ground-truth lesion volume. Non-uniform dose-painting plans using volumetrically modulated arc therapy were optimized for fixed normal lung and spinal cord objectives and variable PET-based target objectives. Resulting plans were delivered to a cylindrical diode array at rest, in motion on a platform driven by the same respiratory patterns (3D), or motion-compensated by a robotic couch with an infrared camera tracking system (4D). Errors were estimated relative to the static ground truth condition for mean target-to-background (T/Bmean) ratios, target volumes, planned equivalent uniform target doses, and 2%-2 mm gamma delivery passing rates. Relative to motionless ground truth conditions, PET/CT imaging errors were on the order of 10-20%, treatment planning errors were 5-10%, and treatment delivery errors were 5-30% without motion compensation. Errors from residual motion following compensation methods were reduced to 5-10% in PET/CT imaging, PET/CT imaging to RT planning, and RT delivery under a dose painting paradigm is feasible within an integrated respiratory motion phantom workflow. For a limited set of cases, the magnitude

Wall stress on ascending thoracic aortic aneurysms with bicuspid compared with tricuspid aortic valve.

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Xuan, Yue; Wang, Zhongjie; Liu, Raymond; Haraldsson, Henrik; Hope, Michael D; Saloner, David A; Guccione, Julius M; Ge, Liang; Tseng, Elaine

2018-03-08

Guidelines for repair of bicuspid aortic valve-associated ascending thoracic aortic aneurysms have been changing, most recently to the same criteria as tricuspid aortic valve-ascending thoracic aortic aneurysms. Rupture/dissection occurs when wall stress exceeds wall strength. Recent studies suggest similar strength of bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms; thus, comparative wall stress may better predict dissection in bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms. Our aim was to determine whether bicuspid aortic valve-ascending thoracic aortic aneurysms had higher wall stresses than their tricuspid aortic valve counterparts. Patients with bicuspid aortic valve- and tricuspid aortic valve-ascending thoracic aortic aneurysms (bicuspid aortic valve = 17, tricuspid aortic valve = 19) greater than 4.5 cm underwent electrocardiogram-gated computed tomography angiography. Patient-specific 3-dimensional geometry was reconstructed and loaded to systemic pressure after accounting for prestress geometry. Finite element analyses were performed using the LS-DYNA solver (LSTC Inc, Livermore, Calif) with user-defined fiber-embedded material model to determine ascending thoracic aortic aneurysm wall stress. Bicuspid aortic valve-ascending thoracic aortic aneurysms 99th-percentile longitudinal stresses were 280 kPa versus 242 kPa (P = .028) for tricuspid aortic valve-ascending thoracic aortic aneurysms in systole. These stresses did not correlate to diameter for bicuspid aortic valve-ascending thoracic aortic aneurysms (r = -0.004) but had better correlation to tricuspid aortic valve-ascending thoracic aortic aneurysms diameter (r = 0.677). Longitudinal stresses on sinotubular junction were significantly higher in bicuspid aortic valve-ascending thoracic aortic aneurysms than in tricuspid aortic valve-ascending thoracic aortic aneurysms (405 vs 329 kPa, P = .023). Bicuspid

Lipolysis of emulsion models of triglyceride-rich lipoproteins is altered in male patients with abdominal aorta aneurysm

Directory of Open Access Journals (Sweden)

J.J. Hosni

2007-03-01

Full Text Available Disorders of the lipid metabolism may play a role in the genesis of abdominal aorta aneurysm. The present study examined the intravascular catabolism of chylomicrons, the lipoproteins that carry the dietary lipids absorbed by the intestine in the circulation in patients with abdominal aorta aneurysm. Thirteen male patients (72 ± 5 years with abdominal aorta aneurysm with normal plasma lipid profile and 13 healthy male control subjects (73 ± 5 years participated in the study. The method of chylomicron-like emulsions was used to evaluate this metabolism. The emulsion labeled with 14C-cholesteryl oleate and ³H-triolein was injected intravenously in both groups. Blood samples were taken at regular intervals over 60 min to determine the decay curves. The fractional clearance rate (FCR of the radioactive labels was calculated by compartmental analysis. The FCR of the emulsion with ³H-triolein was smaller in the aortic aneurysm patients than in controls (0.025 ± 0.017 vs 0.039 ± 0.019 min-1; P < 0.05, but the FCR of14C-cholesteryl oleate of both groups did not differ. In conclusion, as indicated by the triglyceride FCR, chylomicron lipolysis is diminished in male patients with aortic aneurysm, whereas the remnant removal which is traced by the cholesteryl oleate FCR is not altered. The results suggest that defects in the chylomicron metabolism may represent a risk factor for development of abdominal aortic aneurysm.

Serial position learning effects in patients with aneurysms of the anterior communicating artery.

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Stefanova, Elka; Kostic, Vladimir S; Ziropadja, Ljubomir; Markovic, Milan; Ocic, Gordana

2002-08-01

Ruptured and repaired Anterior Communicating Artery (ACoA) aneurysm can result in devastating impairments involving memory, executive function, confabulation, and personality changes. This study tested serial position learning effects (SPEs) in patients following repaired and ruptured ACoA aneurysm, using results on the Rey Auditory Verbal Learning Test (RAVLT). Thirty patients with ruptured aneurysms of the ACoA and 31 matched controls were included in the study. The primacy-recency effects were maintained during five learning trials in ACoA group, albeit at an overall lower level than in the controls. There was no difference in primacy-recency relation across five learning trials in ACoA group. On the delayed recall trial the patient group demonstrated neither a primacy, nor a recency phenomenon, reflecting a lack of recall of any parts of the word list. This kind of primacy-recency profile across learning trials in ACoA group has no similarity with SPE results in frontal lesion groups, or with SPE distributions in other amnesic disorders, despite the fact that memory and executive deficits were evident in our ACoA group.

Abdominal aortic aneurysm neck remodeling after Anaconda stent graft implantation.

Science.gov (United States)

Vukovic, Elisabeth; Czerny, Martin; Beyersdorf, Friedhelm; Wolkewitz, Martin; Berezowski, Mikolaj; Siepe, Matthias; Blanke, Philipp; Rylski, Bartosz

2018-05-24

The aim of this study was to define how the proximal landing zone changes geometrically after endovascular abdominal aortic aneurysm repair (EVAR) with the Anaconda (Vascutek, Inchinnan, United Kingdom) stent graft. Among 230 patients who underwent Anaconda stent graft implantation between 2005 and 2014, we included 126 with adequate computed tomography (CT) image quality and follow-up. CT analysis entailed the geometric changes in the main body, proximal rings, and proximal landing zone. The median CT follow-up was 2.0 years (345.8 patients-years). The proximal portion of the main body ring system flattened within the first year after EVAR, resulting in an up to 30° increase in the upper ring's angle in 40% patients and up to 40° increase in 24% patients. One year after EVAR, the upper ring angle increase slowed down. Aortic diameter measured at the level of the upper and lower ring expanded by 2 to 4 mm within 1 year, but remained unchanged afterward. The main body migrated continuously down toward the aortic bifurcation, attaining an average 6-mm increase in the distance between the superior mesenteric artery and main body within 4 years. Freedom from endoleak type IA was 95 ± 2% and 93 ± 3% after 1 and 4 years, respectively. The Anaconda main body ring system in its proximal portion flattens within the first year after EVAR, leading to an increase of 2 to 4 mm in the proximal landing zone's aortic diameter. The main body migrates slowly but continuously down toward the aortic bifurcation. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Institutional Patient-specific IMRT QA Does Not Predict Unacceptable Plan Delivery

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Kry, Stephen F., E-mail: sfkry@mdanderson.org [Imaging and Radiation Oncology Core at Houston, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Molineu, Andrea [Imaging and Radiation Oncology Core at Houston, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kerns, James R.; Faught, Austin M.; Huang, Jessie Y.; Pulliam, Kiley B.; Tonigan, Jackie [Imaging and Radiation Oncology Core at Houston, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); The University of Texas Health Science Center Houston, Graduate School of Biomedical Sciences, Houston, Texas (United States); Alvarez, Paola [Imaging and Radiation Oncology Core at Houston, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Stingo, Francesco [The University of Texas Health Science Center Houston, Graduate School of Biomedical Sciences, Houston, Texas (United States); Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Followill, David S. [Imaging and Radiation Oncology Core at Houston, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); The University of Texas Health Science Center Houston, Graduate School of Biomedical Sciences, Houston, Texas (United States)

2014-12-01

Purpose: To determine whether in-house patient-specific intensity modulated radiation therapy quality assurance (IMRT QA) results predict Imaging and Radiation Oncology Core (IROC)-Houston phantom results. Methods and Materials: IROC Houston's IMRT head and neck phantoms have been irradiated by numerous institutions as part of clinical trial credentialing. We retrospectively compared these phantom results with those of in-house IMRT QA (following the institution's clinical process) for 855 irradiations performed between 2003 and 2013. The sensitivity and specificity of IMRT QA to detect unacceptable or acceptable plans were determined relative to the IROC Houston phantom results. Additional analyses evaluated specific IMRT QA dosimeters and analysis methods. Results: IMRT QA universally showed poor sensitivity relative to the head and neck phantom, that is, poor ability to predict a failing IROC Houston phantom result. Depending on how the IMRT QA results were interpreted, overall sensitivity ranged from 2% to 18%. For different IMRT QA methods, sensitivity ranged from 3% to 54%. Although the observed sensitivity was particularly poor at clinical thresholds (eg 3% dose difference or 90% of pixels passing gamma), receiver operator characteristic analysis indicated that no threshold showed good sensitivity and specificity for the devices evaluated. Conclusions: IMRT QA is not a reasonable replacement for a credentialing phantom. Moreover, the particularly poor agreement between IMRT QA and the IROC Houston phantoms highlights surprising inconsistency in the QA process.

Institutional Patient-specific IMRT QA Does Not Predict Unacceptable Plan Delivery

International Nuclear Information System (INIS)

Kry, Stephen F.; Molineu, Andrea; Kerns, James R.; Faught, Austin M.; Huang, Jessie Y.; Pulliam, Kiley B.; Tonigan, Jackie; Alvarez, Paola; Stingo, Francesco; Followill, David S.

2014-01-01

Purpose: To determine whether in-house patient-specific intensity modulated radiation therapy quality assurance (IMRT QA) results predict Imaging and Radiation Oncology Core (IROC)-Houston phantom results. Methods and Materials: IROC Houston's IMRT head and neck phantoms have been irradiated by numerous institutions as part of clinical trial credentialing. We retrospectively compared these phantom results with those of in-house IMRT QA (following the institution's clinical process) for 855 irradiations performed between 2003 and 2013. The sensitivity and specificity of IMRT QA to detect unacceptable or acceptable plans were determined relative to the IROC Houston phantom results. Additional analyses evaluated specific IMRT QA dosimeters and analysis methods. Results: IMRT QA universally showed poor sensitivity relative to the head and neck phantom, that is, poor ability to predict a failing IROC Houston phantom result. Depending on how the IMRT QA results were interpreted, overall sensitivity ranged from 2% to 18%. For different IMRT QA methods, sensitivity ranged from 3% to 54%. Although the observed sensitivity was particularly poor at clinical thresholds (eg 3% dose difference or 90% of pixels passing gamma), receiver operator characteristic analysis indicated that no threshold showed good sensitivity and specificity for the devices evaluated. Conclusions: IMRT QA is not a reasonable replacement for a credentialing phantom. Moreover, the particularly poor agreement between IMRT QA and the IROC Houston phantoms highlights surprising inconsistency in the QA process

Impact of Right-Sided Aneurysm, Rupture Status, and Size of Aneurysm on Perforator Infarction Following Microsurgical Clipping of Posterior Communicating Artery Aneurysms with a Distal Transsylvian Approach.

Science.gov (United States)

Tanabe, Jun; Ishikawa, Tatsuya; Moroi, Junta; Sakata, Yoshinori; Hadeishi, Hiromu

2018-03-01

Posterior communicating artery (PCoA) aneurysms are among the most common aneurysms. Because blockage of the PCoA and perforators can cause adverse outcomes, occlusion of these arteries by surgical clipping should be avoided. The impact of factors on PCoA perforator infarction when using a distal transsylvian approach for PCoA aneurysms was examined. A total of 183 patients underwent PCoA aneurysm clipping, excluding application of fenestrated clips. Patients were divided into 2 groups: patients with PCoA perforator infarction (infarction group) and patients without infarction (noninfarction group). Multiple factors were analyzed in the 2 groups. Twenty-two of the 183 patients (12.0%) showed perforator infarction, mainly on magnetic resonance imaging evaluation, resulting in permanent deficits in 2 patients (1.1%). The proportion of right-sided operations (86.4% vs. 53.4%; P = 0.005) and surgery for rupture (90.9% vs. 55.9%; P = 0.002) were significantly higher in the infarction group than in the noninfarction group. Aneurysms were significantly larger in the infarction group (8.4 ± 3.8 mm) than in the noninfarction group (6.3 ± 3.0 mm; P = 0.02). Ruptured status (odds ratio [OR], 7.35; P = 0.01), right side (OR, 5.19; P = 0.01), and aneurysm size (OR, 1.18; P = 0.02) remained independent predictors of perforator infarction on multivariate logistic regression analysis. Ruptured status, right side, and large PCoA aneurysm were independent predictors of PCoA perforator infarction. Symptoms due to PCoA perforating infarction were mostly transient and rarely affected outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

Inter-observer variability in diagnosing radiological features of aneurysmal subarachnoid hemorrhage; a preliminary single centre study comparing observers from different specialties and levels of training.

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Siddiqui, Usman T; Khan, Anjum F; Shamim, Muhammad Shahzad; Hamid, Rana Shoaib; Alam, Muhammad Mehboob; Emaduddin, Muhammad

2014-01-01

A noncontrast computed tomography (CT) scan remains the initial radiological investigation of choice for a patient with suspected aneurysmal subarachnoid hemorrhage (aSAH). This initial scan may be used to derive key information about the underlying aneurysm which may aid in further management. The interpretation, however, is subject to the skill and experience of the interpreting individual. The authors here evaluate the interpretation of such CT scans by different individuals at different levels of training, and in two different specialties (Radiology and Neurosurgery). Initial nonontrast CT scan of 35 patients with aSAH was evaluated independently by four different observers. The observers selected for the study included two from Radiology and two from Neurosurgery at different levels of training; a resident currently in mid training and a resident who had recently graduated from training of each specialty. Measured variables included interpreter's suspicion of presence of subarachnoid blood, side of the subarachnoid hemorrhage, location of the aneurysm, the aneurysm's proximity to vessel bifurcation, number of aneurysm(s), contour of aneurysm(s), presence of intraventricular hemorrhage (IVH), intracerebral hemorrhage (ICH), infarction, hydrocephalus and midline shift. To determine the inter-observer variability (IOV), weighted kappa values were calculated. There was moderate agreement on most of the CT scan findings among all observers. Substantial agreement was found amongst all observers for hydrocephalus, IVH, and ICH. Lowest agreement rates were seen in the location of aneurysm being supra or infra tentorial. There were, however, some noteworthy exceptions. There was substantial to almost perfect agreement between the radiology graduate and radiology resident on most CT findings. The lowest agreement was found between the neurosurgery graduate and the radiology graduate. Our study suggests that although agreements were seen in the interpretation of some of

Hybrid endovascular treatment of an aortic root and thoracoabdominal aneurysm in a high-risk patient with Marfan syndrome.

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Gelpi, Guido; Mazzaccaro, Daniela; Romagnoni, Claudia; Contino, Monica; Antona, Carlo

2013-05-01

This report describes the hybrid endovascular treatment of an aortic root dilatation and a thoracoabdominal aneurysm in a high-risk patient with Marfan syndrome. A 50-year-old male, in hemodialysis for polycystic kidney and polycystic liver, was referred to our department for aortic root dilatation of 5 cm and a 6.3-cm thoracoabdominal aneurysm . He already underwent surgical repair of abdominal aortic aneurysm 10 years ago, complicated by pseudoaneurysm of the proximal anastomosis that had been treated in another center, with an endoprosthesis. The patient underwent aortic root replacement, aortic valve sparing operation, and rerouting of the superior mesenteric artery and celiac trunk to the ascending aorta. The thoracoabdominal aneurysm was excluded with an endoprosthesis few days after the surgical step. The 12-month computed tomography scan confirmed the complete exclusion of the thoracoabdominal aneurysm.

Oculomotor nerve palsy by posterior communicating artery aneurysms: influence of surgical strategy on recovery.

Science.gov (United States)

Güresir, Erdem; Schuss, Patrick; Seifert, Volker; Vatter, Hartmut

2012-11-01

Resolution of oculomotor nerve palsy (ONP) after clipping of posterior communicating artery (PCoA) aneurysms has been well documented. However, whether additional decompression of the oculomotor nerve via aneurysm sac dissection or resection is superior to pure aneurysm clipping is the subject of much debate. Therefore, the objective in the present investigation was to analyze the influence of surgical strategy--specifically, clipping with or without aneurysm dissection--on ONP resolution. Between June 1999 and December 2010, 18 consecutive patients with ruptured and unruptured PCoA aneurysms causing ONP were treated at the authors' institution. Oculomotor nerve palsy was evaluated on admission and at follow-up. The electronic database MEDLINE was searched for additional data in published studies of PCoA aneurysms causing ONP. Two reviewers independently extracted data. Overall, 8 studies from the literature review and 6 patients in the current series (121 PCoA aneurysms) met the study inclusion criteria. Ninety-four aneurysms were treated with simple aneurysm neck clipping and 27 with clipping plus aneurysm sac decompression. The surgical strategy, simple aneurysm neck clipping versus clipping plus oculomotor nerve decompression, had no effect on full ONP resolution on univariate (p = 0.5) and multivariate analyses. On multivariate analysis, patients with incomplete ONP at admission were more likely to have full resolution of the palsy than were those with complete ONP at admission (p = 0.03, OR = 4.2, 95% CI 1.1-16). Data in the present study indicated that ONP caused by PCoA aneurysms improves after clipping without and with oculomotor nerve decompression. The resolution of ONP is inversely associated with the initial severity of ONP.

Assessment of CT dose to the fetus and pregnant female patient using patient-specific computational models

DEFF Research Database (Denmark)

Xie, Tianwu; Poletti, Pierre-Alexandre; Platon, Alexandra

2018-01-01

of pregnant patients and the embedded foetus, we developed a methodology for construction of patient-specific voxel-based computational phantoms based on existing standardised hybrid computational pregnant female phantoms. We estimated the maternal absorbed dose and foetal organ dose for 30 pregnant patients...... for assessment of the radiation risks to pregnant patients and the foetus from various CT scanning protocols, thus guiding the decision-making process. KEY POINTS: • In CT examinations, the absorbed dose is non-uniformly distributed within foetal organs. • This work reports, for the first time, estimates...

Impact of Aneurysm Projection on Intraoperative Complications During Surgical Clipping of Ruptured Posterior Communicating Artery Aneurysms.

Science.gov (United States)

Fukuda, Hitoshi; Hayashi, Kosuke; Yoshino, Kumiko; Koyama, Takashi; Lo, Benjamin; Kurosaki, Yoshitaka; Yamagata, Sen

2016-03-01

Surgical clipping of ruptured posterior communicating artery (PCoA) aneurysms is a well-established procedure to date. However, preoperative factors associated with procedure-related risk require further elucidation. To investigate the impact of the direction of aneurysm projection on the incidence of procedure-related complications during surgical clipping of ruptured PCoA aneurysms. A total of 65 patients with ruptured PCoA aneurysms who underwent surgical clipping were retrospectively analyzed from a single-center, prospective, observational cohort database in this study. The aneurysms were categorized into lateral and posterior projection groups, depending on direction of the dome. Characteristics and operative findings of each projection group were identified. We also evaluated any correlation of aneurysm projection with the incidence of procedure-related complications. Patients with ruptured PCoA aneurysms with posterior projection more likely presented with good-admission-grade subarachnoid hemorrhage (P = .01, χ test) and were less to also have intracerebral hematoma (P = .01). These aneurysms were found to be associated with higher incidence of intraoperative rupture (P = .02), complex clipping with fenestrated clips (P = .02), and dense adherence to PCoA or its perforators (P = .04) by univariate analysis. Aneurysms with posterior projection were also correlated with procedure-related complications, including postoperative cerebral infarction or hematoma formation (odds ratio, 5.87; 95% confidence interval, 1.11-31.1; P = .04) by multivariable analysis. Ruptured PCoA aneurysms with posterior projection carried a higher risk of procedure-related complications of surgical clipping than those with lateral projection.

Recurrence of ICA-PCoA aneurysms after neck clipping.

Science.gov (United States)

Sakaki, T; Takeshima, T; Tominaga, M; Hashimoto, H; Kawaguchi, S

1994-01-01

Between 1975 and 1992, 2211 patients underwent aneurysmal neck clipping at the Nara Medical University clinic and associated hospitals. The aneurysm in 931 of these patients was situated at the junction of the internal carotid artery (ICA) and posterior communicating artery (PCoA). Seven patients were readmitted 4 to 17 years after the first surgery because of regrowth and rupture of an ICA-PCoA aneurysmal sac that had arisen from the residual neck. On angiograms obtained following aneurysmal neck clipping, a large primitive type of PCoA was demonstrated in six patients and a small PCoA in one. A small residual aneurysm was confirmed in only two patients and angiographically complete neck clipping in five. Recurrent ICA-PCoA aneurysms were separated into two types based on the position of the old clip in relation to the new growth. Type 1 aneurysms regrow from the entire neck and balloon eccentrically. In this type, it is possible to apply the clip at the neck as in conventional clipping for a ruptured aneurysm. Type 2 includes aneurysms in which the proximal portion of a previous clip is situated at the corner of the ICA and aneurysmal neck and the distal portion on the enlarged dome of the aneurysm, because the sac is regrowing from a portion of the residual neck. In this type of aneurysm, a Sugita fenestrated clip can occlude the residual neck, overriding the old clip. Classifying these aneurysms into two groups is very useful from a surgical point of view because it is possible to apply a new clip without removing the old clip, which was found to be adherent to surrounding tissue.

A new self-expanding nitinol stent (Enterprise) for the treatment of wide-necked intracranial aneurysms: initial clinical and angiographic results in 31 aneurysms

Energy Technology Data Exchange (ETDEWEB)

Weber, Werner; Kuehne, Dietmar [Alfried Krupp Hospital, Department of Radiology and Neuroradiology, Essen (Germany); Bendszus, Martin; Solymosi, Laszlo [University of Wuerzburg, Department of Neuroradiology, Wuerzburg (Germany); Kis, Bernhard [University of Duisburg-Essen, Research Unit, Rheinische Kliniken Essen, Department of Psychiatry and Psychotherapy, Essen (Germany); Boulanger, Thierry [Centre Hospitalier of Luxembourg, Service of Neuroradiology, Luxembourg (Luxembourg)

2007-07-15

We report the results of a prospective clinical study using a new self-expanding nitinol stent (Enterprise) designed for the treatment of wide-necked intracranial aneurysms. We treated 31 saccular, wide-necked intracranial aneurysms in 30 patients. Ten aneurysms had recanalized after prior endovascular treatment without a stent, and 21 aneurysms had not been treated before. Stent deployment was successful in all procedures. Additional coil embolization was performed in all aneurysms. Initial complete angiographic occlusion was achieved in 6 aneurysms, a neck remnant was left in 18 aneurysms and there were 7 residual aneurysms. Angiographic follow-up examinations of 30 lesions after 6 months demonstrated 15 complete occlusions, 8 neck remnants and 7 residual aneurysms. One patient refused the 6-month angiographic follow-up. Spontaneous occlusion of the aneurysm had occurred in 14 patients, and 6 aneurysms showed recanalization. Four of these residual aneurysms were retreated. At the 6-month follow-up, 29 parent arteries were unaffected, whereas two parent vessels demonstrated minor asymptomatic narrowing at the stent site. Two patients experienced one or more possible or probable device-related serious adverse events during the 6-month follow-up period. There was no procedural morbidity or mortality at 6 months after the procedure. The reported results demonstrated the safety and feasibility of the Cordis Neurovascular Enterprise stent in the treatment of wide-necked intracranial aneurysms. Initial clinical and angiographic results are favorable. (orig.)

Vascular Variations Associated with Intracranial Aneurysms.

Science.gov (United States)

Orakdogen, Metin; Emon, Selin Tural; Somay, Hakan; Engin, Taner; Is, Merih; Hakan, Tayfun

2017-01-01

To investigate the vascular variations in patients with intracranial aneurysm in circle of Willis. We used the data on 128 consecutive intracranial aneurysm cases. Cerebral angiography images were analyzed retrospectively. Arteries were grouped as anterior cerebral arterial system (ACS), posterior cerebral arterial system (PCS) and middle cerebral arterial system (MCS) for grouping vascular variations. Lateralization, being single/multiple, gender; and also any connection with accompanying aneurysms" number, localization, dimension, whether bleeding/incidental aneurysm has been inspected. Variations were demonstrated in 57.8% of the cases. The most common variation was A1 variation (34.4%). The rate of variations was 36.7%, 24.2% and 10.2% respectively in ACS, PCS and MCS. MCS variations were significantly higher in males. Anterior communicating artery (ACoA) aneurysm observance rates were significantly higher and posterior communicating artery (PCoA) aneurysm and middle cerebral artery (MCA) aneurysm observance rates were significantly lower when compared to "no ACS variation detected" cases. In "PCS variation detected" cases, PCoA aneurysm observance rates and coexistence of multiple variations were significantly higher. The rate of vascular variations in patients with aneurysms was 57.8%. Arterial hypoplasia and aplasia were the most common variations. ACS was the most common region that variations were located in; they were mostly detected on the right side. Coexistence of ACoA aneurysm was higher than PCoA and MCA aneurysms. In the PCS variations group, PCoA aneurysms were the most common aneurysms that accompanying the variation and multiple variations were more common than in the other two groups. The variations in MCS were most common in males.

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

Directory of Open Access Journals (Sweden)

Nan Lv

Full Text Available The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA aneurysms.In 129 PCoA aneurysms (85 ruptured, 44 unruptured, clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms.While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR, size ratio (SR, dome-to-neck ratio (DN, inflow angle (IA, normalized wall shear stress (NWSS and percentage of low wall shear stress area (LSA were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001 and LSA (OR = 1.393, p = 0.041.Hemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms.

Abciximab in the treatment of acute in-stent thrombosis in patient with intracranial aneurysm

International Nuclear Information System (INIS)

Lilov, M.; Juszkat, R.; Petkov, A.; Todorov, I.

2009-01-01

A case of endovascular therapy via embolization of aneurysm in patient with SAH is performed selective brain angiography and find 3 aneurysms. The first is in right segment M1-M2 with diameter 5 mm, the second with wide neck is in supraclinoid portion of right internal carotid artery and the third in left M1-M2 segment. One month after embolization of ruptured aneurysm with coils BALT (Montmorency, France) and previous anticoagulation therapy was applied Leo stent (SALT) intraluminal in left internal carotid artery. Developed acute instent thrombosis recanalized with intraarterial use of abciximab. (authors)

Interventional procedures of the isolated iliac arterial aneurysm

Energy Technology Data Exchange (ETDEWEB)

Ohm, Joon Young [The Catholic Univ. of Korea College of Medicine, Bucheon (Korea, Republic of); Shin, Byung Seok; Ahn, Moon Sang [Chungnam National Univ. Hospital, Daejeon (Korea, Republic of); Park, Mi Hyun [Dankook Univ. Hospital, Cheonan (Korea, Republic of); Kim, Ho Jun [Konyang Univ. Hospital, Daejeon (Korea, Republic of)

2012-05-15

To report the results of treatment isolated iliac arterial aneurysms by interventional procedures. Over a period of 5 years, 7 isolated iliac artery aneurysms (4 in the common iliac artery, 3 in the internal iliac artery) in 7 patients (3 women, 4 men; mean age, 65.7 years) were treated using interventional procedures. The mean aneurysm size was 35 mm (range, 30-45 mm). The common iliac aneurysms were treated using a unilateral stent graft (2 balloon expandable, 2 self expandable) with coil embolization of the internal iliac artery (n = 3), except for 1 aneurysm that ruptured. Coil embolization alone was performed for aneurysms involving only the internal iliac artery (n = 3). All patients were treated successfully, except for 1 with an initial remnant of type 2 endoleak. There were no perioperative complications. No leakage or complication occurred at the mean follow up of 14 months (range 2-29 months). One patient with a ruptured aneurysm died of multi organ failure during the follow up period. Three aneurysms had decreased in size on follow up CT. Interventional procedures with stent grafting and coil embolization are safe and effective treatments for isolated iliac artery aneurysms.

Performance of language tasks in patients with ruptured aneurysm of the left hemisphere worses in the post-surgical evaluation

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Ana Cláudia C. Vieira

2016-08-01

Full Text Available ABSTRACT Sub-arachnoid hemorrhage (SAH promotes impairment of upper cortical functions. However, few information is available emphasizing changes in language after aneurismal SAH and aneurysm location influence. Objective To assess the language and verbal fluency performance in aneurismal SAH pre- and post-surgery in patients caused by an aneurysm of the anterior communicating artery (AcomA, left middle cerebral artery (L-MCA and left posterior comunicating artery (L-PcomA. Methods Assessment in 79 patients with SAH, on two occasions: pre- and post surgical treatment. They were divided into three groups by the aneurysms’ location. Results Deterioration is detected in the performance of all patients during the post-surgical period; L-MCA aneurysm patients displayed a reduction in verbal naming and fluency; L-PcomA patients deteriorated in the written language and fluency tasks. Conclusion After the surgical procedure the patients decreased in various language tasks and these differences in performance being directly related to the location of the aneurysm.

Mathematical phantoms for evaluation of age-specific internal dose

International Nuclear Information System (INIS)

Cristy, M.

1980-01-01

A series of mathematical phantoms representing children has been developed for use with photon transport codes. These phantoms, patterned after the Fisher-Snyder adult phantom, consist of simple mathematical expressions for the boundaries of the major organs and body sections. The location and shape of the organs are consistent with drawings depicting developmental anatomy, with the organ volumes assigned such that the masses at the various ages conform closely with the data presented in Reference Man. The explicit mathematical expressions for the various ages overcome the potential misrepresentation of organ sizes that occurred in phantoms derived from simple mathematical transformations of the adult phantom. Female breast tissue has been added to the phantoms, including the adult, now allowing assessment of doses to this organ

Calculating patient specific doses in X-ray diagnostics and from radiopharmaceuticals

International Nuclear Information System (INIS)

Lampinen, J.

2000-01-01

The risk associated with exposure to ionising radiation is dependent on the characteristics of the exposed individual. The size and structure of the individual influences the absorbed dose distribution in the organs. Traditional methods used to calculate the patient organ doses are based on standardised calculation phantoms, which neglect the variance of the patient size or even sex. When estimating the radiation dose of an individual patient, patient specific calculation methods must be used. Methods for patient specific dosimetry in the fields of X-ray diagnostics and diagnostic and therapeutic use of radiopharmaceuticals were proposed in this thesis. A computer program, ODS-60, for calculating organ doses from diagnostic X-ray exposures was presented. The calculation is done in a patient specific phantom with depth dose and profile algorithms fitted to Monte Carlo simulation data from a previous study. Improvements to the version reported earlier were introduced, e.g. bone attenuation was implemented. The applicability of the program to determine patient doses from complex X-ray examinations (barium enema examination) was studied. The conversion equations derived for female and male patients as a function of patient weight gave the smallest deviation from the actual patient doses when compared to previous studies. Another computer program, Intdose, was presented for calculation of the dose distribution from radiopharmaceuticals. The calculation is based on convolution of an isotope specific point dose kernel with activity distribution, obtained from single photon emission computed tomography (SPECT) images. Anatomical information is taken from magnetic resonance (MR) or computed tomography (CT) images. According to a phantom study, Intdose agreed within 3 % with measurements. For volunteers administered diagnostic radiopharmaceuticals, the results given by Intdose were found to agree with traditional methods in cases of medium sized patients. For patients

A novel composite material specifically developed for ultrasound bone phantoms: cortical, trabecular and skull

International Nuclear Information System (INIS)

Wydra, A; Maev, R Gr

2013-01-01

In the various stages of developing diagnostic and therapeutic equipment, the use of phantoms can play a very important role in improving the process, help in implementation, testing and calibrations. Phantoms are especially useful in developing new applications and training new doctors in medical schools. However, devices that use different physical factors, such as MRI, Ultrasound, CT Scan, etc will require the phantom to be made of different physical properties. In this paper we introduce the properties of recently designed new materials for developing phantoms for ultrasonic human body investigation, which in today's market make up more than 30% in the world of phantoms. We developed a novel composite material which allows fabrication of various kinds of ultrasound bone phantoms to mimic most of the acoustical properties of human bones. In contrast to the ex vivo tissues, the proposed material can maintain the physical and acoustical properties unchanged for long periods of time; moreover, these properties can be custom designed and created to suit specific needs. As a result, we introduce three examples of ultrasound phantoms that we manufactured in our laboratory: cortical, trabecular and skull bone phantoms. The paper also presents the results of a comparison study between the acoustical and physical properties of actual human bones (reported in the referenced literatures) and the phantoms manufactured by us. (note)

Comparison of MR angiography with conventional angiography in cervical and intracranial vascular disease

International Nuclear Information System (INIS)

Choi, D. S.; Chang, K. H.; Jung, H. W.; Han, M. H.

1995-01-01

To assess the usefulness of magnetic resonance angiography (MRA) in evaluation of stenosis of carotid and large cerebral vessels and cerebral aneurysm. Twenty-seven patients with either arterial stenosis in cervical or intracranial major vessels (n = 18) or cerebral aneurysm (n = 8) or both (n 1) were examined with both MRA and conventional angiography (CA). MRA was performed with 3D TOF technique with magnetization transfer suppression at 1.5T system (Magnetom, Siemens, Germany); both intracranial MRA and cervical MRA in 16 patients, intracranial MRA only in the remaining patients. For evaluation of arterial stenosis, 32 carotid bifurcations and 383 segments of intracranial major vessels were assessed in blind fashion, and were compared with those of CA. Each arterial segment was arbitrarily classified into one of five grades (< 10, 10-49, 50-74, 75-99, 100%) for carotid bifurcation and one of four (< 10, 10-49, 50-99, 100%) for intracranial vessels. For aneurysm, its location, size shape and direction were compared. For arterial stenosis, concordance rate between MRA and CA was 88% (28/32) in carotid bifurcation and 89% (340/383) in intracranial vessels. All discordant cases were overgraded on MRA. For aneurysm, 7 of 9 were demonstrated on both MRA and CA, one of which was partially demonstrated on MRA. One of the other two patients showed aneurysm only on MRA, whereas the remaining one revealed aneurysm only on CA. MRA may be performed as a screening test for occlusive disease of cervical and major intracranial vessels and cerebral aneurysm

Y stenting assisted coiling using a new low profile visible intraluminal support device for wide necked basilar tip aneurysms: a technical report.

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Conrad, Marcelo D; Brasiliense, Leonardo B C; Richie, Alexa N; Hanel, Ricardo A

2014-05-01

Many endovascular techniques have been described in recent years for the management of wide necked aneurysms. The Y stent assisted technique has been generally used for coil embolization of wide necked bifurcation aneurysms. This technique was first described for the treatment of basilar tip aneurysms in combination with several different devices, demonstrating encouraging results. We report the results of the first two cases of wide necked basilar tip aneurysms treated with Y stent assisted coil embolization using a new low profile visible intraluminal stent (LVIS Jr; MicroVention, Tustin, California, USA) delivered through a 0.017 inch microcatheter. We also reviewed the literature comparing other endovascular techniques (coiling alone, stent assisted coiling, and Y stent assisted coiling) for wide necked aneurysms. The LVIS Jr device offers a new option for the treatment of these challenging lesions, with clear advantages over currently available intracranial stents. Larger series and long term results are needed to confirm the applicability and durability of this technique/technology.

Transluminal color-coded three-dimensional magnetic resonance angiography for visualization of signal Intensity distribution pattern within an unruptured cerebral aneurysm: preliminarily assessment with anterior communicating artery aneurysms

International Nuclear Information System (INIS)

Satoh, T.; Ekino, C.; Ohsako, C.

2004-01-01

The natural history of unruptured cerebral aneurysm is not known; also unknown is the potential growth and rupture in any individual aneurysm. The authors have developed transluminal color-coded three-dimensional magnetic resonance angiography (MRA) obtained by a time-of-flight sequence to investigate the interaction between the intra-aneurysmal signal intensity distribution patterns and configuration of unruptured cerebral aneurysms. Transluminal color-coded images were reconstructed from volume data of source magnetic resonance angiography by using a parallel volume-rendering algorithm with transluminal imaging technique. By selecting a numerical threshold range from a signal intensity opacity chart of the three-dimensional volume-rendering dataset several areas of signal intensity were depicted, assigned different colors, and visualized transparently through the walls of parent arteries and an aneurysm. Patterns of signal intensity distribution were analyzed with three operated cases of an unruptured anterior communicating artery aneurysm and compared with the actual configurations observed at microneurosurgery. A little difference in marginal features of an aneurysm was observed; however, transluminal color-coded images visualized the complex signal intensity distribution within an aneurysm in conjunction with aneurysmal geometry. Transluminal color-coded three-dimensional magnetic resonance angiography can thus provide numerical analysis of the interaction between spatial signal intensity distribution patterns and aneurysmal configurations and may offer an alternative and practical method to investigate the patient-specific natural history of individual unruptured cerebral aneurysms. (orig.)

Performance of an automatic dose control system for CT. Specifications and basic phantom tests

Energy Technology Data Exchange (ETDEWEB)

Nagel, H.D. [Wissenschaft und Technik fuer die Radiolgoe, Dr. HD Nagel, Buchholz (Germany); Stumpp, P.; Kahn, T.; Gosch, D. [Universitaetsklinikum Leipzig (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie

2011-01-15

Purpose: To assess the performance and to provide more detailed insight into the characteristics and limitations of devices for automatic dose control (ADC) in CT. Materials and Methods: A comprehensive study on DoseRight 2.0, the ADC system provided by Philips for its Brilliance CT scanners, was conducted. Phantom tests were carried out on a 64-slice scanner (Brilliance 64) using assorted quality control (QC) phantoms that allowed verification of the basic specifications. If feasible, the findings were verified by model calculations based on known specifications. Results: For all tests, the dose reductions and modulation characteristics fully met the values expected from the specifications. Adverse effects due to increased image noise were only moderate as a result of the 'adequate noise system' design that employs comparatively gentle modulation, and the additional use of adaptive filtration. Conclusion: Simple tests with QC phantoms allow evaluation of the most relevant characteristics of devices for ADC in CT. (orig.)

Hemodynamics before and after bleb formation in cerebral aneurysms

Science.gov (United States)

Cebral, Juan R.; Radaelli, Alessandro; Frangi, Alejandro; Putman, Christopher M.

2007-03-01

We investigate whether blebs in cerebral aneurysms form in regions of low or high wall shear stress (WSS), and how the intraaneurysmal hemodynamic pattern changes after bleb formation. Seven intracranial aneurysms harboring well defined blebs were selected from our database and subject-specific computational models were constructed from 3D rotational angiography. For each patient, a second anatomical model representing the aneurysm before bleb formation was constructed by smoothing out the bleb. Computational fluid dynamics simulations were performed under pulsatile flow conditions for both models of each aneurysm. In six of the seven aneurysms, the blebs formed in a region of elevated WSS associated to the inflow jet impaction zone. In one, the bleb formed in a region of low WSS associated to the outflow zone. In this case, the inflow jet maintained a fairly concentrated structure all the way to the outflow zone, while in the other six aneurysms it dispersed after impacting the aneurysm wall. In all aneurysms, once the blebs formed, new flow recirculation regions were formed inside the blebs and the blebs progressed to a state of low WSS. Assuming that blebs form due to a focally damaged arterial wall, these results seem to indicate that the localized injury of the vessel wall may be caused by elevated WSS associated with the inflow jet. However, the final shape of the aneurysm is probably also influenced by the peri-aneurysmal environment that can provide extra structural support via contact with structures such as bone or dura matter.

Bifurcation Behavior Analysis in a Predator-Prey Model

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Nan Wang

2016-01-01

Full Text Available A predator-prey model is studied mathematically and numerically. The aim is to explore how some key factors influence dynamic evolutionary mechanism of steady conversion and bifurcation behavior in predator-prey model. The theoretical works have been pursuing the investigation of the existence and stability of the equilibria, as well as the occurrence of bifurcation behaviors (transcritical bifurcation, saddle-node bifurcation, and Hopf bifurcation, which can deduce a standard parameter controlled relationship and in turn provide a theoretical basis for the numerical simulation. Numerical analysis ensures reliability of the theoretical results and illustrates that three stable equilibria will arise simultaneously in the model. It testifies the existence of Bogdanov-Takens bifurcation, too. It should also be stressed that the dynamic evolutionary mechanism of steady conversion and bifurcation behavior mainly depend on a specific key parameter. In a word, all these results are expected to be of use in the study of the dynamic complexity of ecosystems.

Endovascular Exclusion of an Abdominal Aortic Aneurysm in Patients with Concomitant Abdominal Malignancy: Early Experience

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Choi, You Ri; Chang, Nam Kyu [Chonnam National University Hwasun Hospital, Hwasun (Korea, Republic of); Shin, Hyo Hyun; Oh, Hyun Jun; Kim, Jae Kyu; Choi, Soo Jin Na; Chung, Sang Young [Chonnam National University Hospital, Gwangju (Korea, Republic of); Yim, Nam Yeol [Armed Forces Yangju Hospital, Yangju (Korea, Republic of)

2010-08-15

To assess the outcomes of endovascular aortic aneurysm repair (EVAR) for the treatment of an abdominal aortic aneurysm in patients undergoing curative surgical treatment for concomitant abdominal malignancy. The study included 12 patients with abdominal neoplasia and an abdominal aortic aneurysm (AAA), which was treated by surgery and stent EVAR. The neoplasm consisted of the gastric, colorectal, pancreas, prostate, and gall bladder. The follow up period was 3-21 months (mean 11.8 months). All medical records and imaging analyses were reviewed by CTA and/or color Doppler US, retrospectively. Successful endoluminal repair was accomplished in all twelve patients. The mean interval time between EVAR and surgery was 58.6 days. Small amounts of type 2 endoleaks were detected in two patients (17%). One patient developed adult respiratory distress syndrome after Whipple's operation 20 days after surgery, which led to hopeless discharge. No procedure-related mortality, morbidity, or graft-related infection was noted. Exclusion of AAA in patients with accompanying malignancy show with a relatively low procedure morbidity and mortality. Hence, endoluminal AAA repair in patients with synchronous neoplasia may allow greater flexibility in the management of an offending malignancy

Endovascular Exclusion of an Abdominal Aortic Aneurysm in Patients with Concomitant Abdominal Malignancy: Early Experience

International Nuclear Information System (INIS)

Choi, You Ri; Chang, Nam Kyu; Shin, Hyo Hyun; Oh, Hyun Jun; Kim, Jae Kyu; Choi, Soo Jin Na; Chung, Sang Young; Yim, Nam Yeol

2010-01-01

To assess the outcomes of endovascular aortic aneurysm repair (EVAR) for the treatment of an abdominal aortic aneurysm in patients undergoing curative surgical treatment for concomitant abdominal malignancy. The study included 12 patients with abdominal neoplasia and an abdominal aortic aneurysm (AAA), which was treated by surgery and stent EVAR. The neoplasm consisted of the gastric, colorectal, pancreas, prostate, and gall bladder. The follow up period was 3-21 months (mean 11.8 months). All medical records and imaging analyses were reviewed by CTA and/or color Doppler US, retrospectively. Successful endoluminal repair was accomplished in all twelve patients. The mean interval time between EVAR and surgery was 58.6 days. Small amounts of type 2 endoleaks were detected in two patients (17%). One patient developed adult respiratory distress syndrome after Whipple's operation 20 days after surgery, which led to hopeless discharge. No procedure-related mortality, morbidity, or graft-related infection was noted. Exclusion of AAA in patients with accompanying malignancy show with a relatively low procedure morbidity and mortality. Hence, endoluminal AAA repair in patients with synchronous neoplasia may allow greater flexibility in the management of an offending malignancy

A coil placement technique to treat intracranial aneurysm with incorporated artery.

Science.gov (United States)

Luo, Chao-Bao; Chang, Feng-Chi; Lin, Chung-Jung; Guo, Wan-Yuo

2018-03-01

Endovascular coil embolization is an accepted treatment option for intracranial aneurysms. However, the coiling of aneurysms with an incorporated artery (IA) poses a high risk of IA occlusion. Here we report our experience of endovascular coil placement using a technique that avoids IA occlusion in aneurysms with IAs. Over a 6-year period, 185 patients harboring 206 intracranial aneurysms underwent endosaccular coiling. Forty-two of these patients with 45 aneurysms were treated by coil placement to avoid IAs occlusion. We assessed the anatomy of the aneurysms and IAs, technical feasibility of the procedure, and degree of aneurysm occlusion. Clinical and angiographic outcomes were assessed as well. Aneurysms were located in the supra-clinoid intracranial internal carotid artery (n = 24), anterior cerebral artery (n = 6), middle cerebral artery (n = 7), and vertebrobasilar artery (n = 8). The IA was at the aneurysm neck in 34 patients, body in 10, and dome in 1. Immediate post-coiling angiogram showed preservation of blood flow through the IA in all aneurysms. Coil compaction with aneurysmal regrowth was found in 7 of 36 patients having follow-up conventional angiography. One patient had an IA territory infarction after embolization. All 42 patients were followed up (mean: 21 months) and showed no re-bleeding. This technique is effective and safe in managing intracranial aneurysms with IAs. Although aneurysmal recurrence may occur in some aneurysms because of insufficient coiling, this technique is simpler to perform and requires less skill than other techniques. It can be an alternative option for treating some selected intracranial aneurysms with IAs. Copyright © 2017. Published by Elsevier Taiwan LLC.

Availability of 111In-labeled platelet scintigraphy in patients with postinfarction left ventricular aneurysm

International Nuclear Information System (INIS)

Tsuda, Takatoshi; Kubota, Masahiro; Iwakubo, Akifumi

1989-01-01

Eighteen patients with postinfarction left ventricular aneurysm (LVA) were examined with indium-111-labeled autologous platelet scintigraphy to identify intracardiac thrombi and to investigate the effect of antithrombotic agents on thrombogenesitiy within the LVA. Indium-111-platelet scintigraphy had a sensitivity of 60% and a specificity of 100% in detecting LVA mural thrombi. Among 6 patients showing false-negative scintigraphic studies, 4 was managed on antiplatelet therapy. Of 9 patients showing active platelet deposition on initial study, including 8 not receiving antiplatelet therapy, 5 were treated with tichlopidine (300 mg/day) for 29.8±5.0 days. For the 5 patients, 2 had resolution and the 3 others had interruption of intraaneurysmal deposition in the second platelet study. For one patient receiving the third platelet study after warfarin therapy, it took two weeks to completely interrupt platelet deposition within the LVA. ECG gated radionuclide ventriculography and thallium-201 myocardial SPECT were also performed to assess left ventricular wall motion of left ventricular ejection fraction (LVEF) and myocardial blood perfusion. Thallium-201 SPECT showed apical or anteroapical perfusion defects. Radionuclide ventriculography pinpointed all 18 apical and anteroseptal aneurysms. A comparison between the thrombus positive group and the thrombus negative group revealed no statistical differences in LVEF and the period from the last myocardial infarction to the initial platelet scanning. These results suggest that indium-111 labeled platelet scintigraphy may be useful for identifying active left ventricular mural thrombi and for judging antiplatelet and anticoagulant therapy. (Namekawa, K)

Resolution of Large Azygos Vein Aneurysm Following Stent-Graft Shunt Placement in a Patient with Ehlers-Danlos Syndrome Type IV

International Nuclear Information System (INIS)

D'Souza, Estelle S.; Williams, David M.; Deeb, G.M.; Cwikiel, Wojciech

2006-01-01

Ehlers-Danlos syndrome (EDS) type IV is a rare connective tissue disorder associated with thin-walled, friable arteries and veins predisposing patients to aneurysm formation, dissection, fistula formation, and vessel rupture. Azygos vein aneurysm is an extremely rare condition which has not been reported in association with EDS in the literature. We present a patient with EDS type IV and interrupted inferior vena cava (IVC) with azygos continuation who developed an azygos vein aneurysm. In order to decrease flow through the azygos vein and reduce the risk of aneurysm rupture, a stent-graft shunt was created from the right hepatic vein to the azygos vein via a transhepatic, retroperitoneal route. At 6 month follow-up the shunt was open and the azygos vein aneurysm had resolved

Computer tomographic phantom

International Nuclear Information System (INIS)

Lonn, A.H.R.; Jacobsen, D.R.; Zech, D.J.

1988-01-01

A reference phantom for computer tomography employs a flexible member with means for urging the flexible member into contact along the curved surface of the lumbar region of a human patient. In one embodiment, the reference phantom is pre-curved in an arc greater than required. Pressure from the weight of a patient laying upon the reference phantom is effective for straightening out the curvature sufficiently to achieve substantial contact along the lumbar region. The curvature of the reference phantom may be additionally distorted by a resilient pad between the resilient phantom and a table for urging it into contact with the lumbar region. In a second embodiment of the invention, a flexible reference phantom is disposed in a slot in the top of a resilient cushion. The resilient cushion and reference phantom may be enclosed in a flexible container. A partially curved reference phantom in a slot in a resilient cushion is also contemplated. (author)

Surgical management of giant posterior communicating artery aneurysms.