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European Radiology Jun 2022• TOF MRA is very important in the evaluation of cerebrovascular stenosis, and a novel evaluation system can further enhance its strengths.• This evaluation system...
• TOF MRA is very important in the evaluation of cerebrovascular stenosis, and a novel evaluation system can further enhance its strengths.• This evaluation system is more accurate based on the fact that cerebral vascular stenosis alters hemodynamics and leads to different imaging presentations.
Topics: Arteries; Cerebral Angiography; Constriction, Pathologic; Humans; Magnetic Resonance Angiography
PubMed: 35076760
DOI: 10.1007/s00330-021-08521-5 -
Computer Methods and Programs in... Mar 2023Automatic segmentation of the cerebral vasculature and aneurysms facilitates incidental detection of aneurysms. The assessment of aneurysm rupture risk assists with...
BACKGROUND AND OBJECTIVES
Automatic segmentation of the cerebral vasculature and aneurysms facilitates incidental detection of aneurysms. The assessment of aneurysm rupture risk assists with pre-operative treatment planning and enables in-silico investigation of cerebral hemodynamics within and in the vicinity of aneurysms. However, ensuring precise and robust segmentation of cerebral vessels and aneurysms in neuroimaging modalities such as three-dimensional rotational angiography (3DRA) is challenging. The vasculature constitutes a small proportion of the image volume, resulting in a large class imbalance (relative to surrounding brain tissue). Additionally, aneurysms and vessels have similar image/appearance characteristics, making it challenging to distinguish the aneurysm sac from the vessel lumen.
METHODS
We propose a novel multi-class convolutional neural network to tackle these challenges and facilitate the automatic segmentation of cerebral vessels and aneurysms in 3DRA images. The proposed model is trained and evaluated on an internal multi-center dataset and an external publicly available challenge dataset.
RESULTS
On the internal clinical dataset, our method consistently outperformed several state-of-the-art approaches for vessel and aneurysm segmentation, achieving an average Dice score of 0.81 (0.15 higher than nnUNet) and an average surface-to-surface error of 0.20 mm (less than the in-plane resolution (0.35 mm/pixel)) for aneurysm segmentation; and an average Dice score of 0.91 and average surface-to-surface error of 0.25 mm for vessel segmentation. In 223 cases of a clinical dataset, our method accurately segmented 190 aneurysm cases.
CONCLUSIONS
The proposed approach can help address class imbalance problems and inter-class interference problems in multi-class segmentation. Besides, this method performs consistently on clinical datasets from four different sources and the generated results are qualified for hemodynamic simulation. Code available at https://github.com/cistib/vessel-aneurysm-segmentation.
Topics: Humans; Deep Learning; Angiography; Neural Networks, Computer; Aneurysm; Brain; Image Processing, Computer-Assisted
PubMed: 36709557
DOI: 10.1016/j.cmpb.2023.107355 -
Journal of Neurological Surgery. Part... Sep 2021Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in...
BACKGROUND
Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in giant intracranial aneurysms (GIAs). In this study, we aimed to reconstruct the circulating and noncirculating parts of GIAs with the time-of-flight (TOF) and motion-sensitized driven-equilibrium (MSDE) sequences with 3D Slicer to reveal an integrated presentation of GIAs, compare its accuracy, and validate the usefulness for preoperative planning.
MATERIAL AND METHODS
Patients with GIAs who were treated with microsurgery in our department were included in this study. Both the TOF and MSDE sequence data for each patient were loaded into 3D Slicer for reconstruction and segmentation. The parameters measured by 3D Slicer were compared with those measured by DSA.
RESULTS
The mean diameter for all GIAs was 28.7 ± 1.5 mm (range, 25.9-31.9 mm). The mean diameter for all GIAs measured by DSA and 3D Slicer was 24.46 ± 5.25 and 28.66 ± 1.48 mm, respectively ( = 4.948, < 0.01). When only the nonthrombotic GIAs were included, the mean diameter measured by DSA and 3D Slicer was 28.69 ± 2.03 and 28.97 ± 1.79 mm, respectively ( = 1.023, = 0.323). The mean aneurysmal volume was 8,292.6 ± 1,175.1 mm and the mean thrombotic volume was 3,590.0 ± 1,003.7 mm.
CONCLUSION
The MSDE sequence brings diagnostic benefits as a comparison to other MRI sequences. Reconstruction of GIAs with 3D Slicer is a low-cost, dependable, and useful supplemental technique for surgical planning.
Topics: Angiography, Digital Subtraction; Cerebral Angiography; Humans; Imaging, Three-Dimensional; Intracranial Aneurysm; Magnetic Resonance Angiography; Microsurgery; Sensitivity and Specificity; Tomography, X-Ray Computed
PubMed: 33583010
DOI: 10.1055/s-0040-1721006 -
Anatomia, Histologia, Embryologia Nov 2020The aim of this study was to compare the arterial vascularization of the pelvic limb between southern caracara (Caracara plancus) and great egret (Ardea alba) by... (Comparative Study)
Comparative Study
The aim of this study was to compare the arterial vascularization of the pelvic limb between southern caracara (Caracara plancus) and great egret (Ardea alba) by dissection and radiographic examinations. Five specimens of caracaras (three males and two females), and seven great egrets (five males and two females) were used. Barium sulphate and latex suspension were injected into the left ventricle of the birds. The radiographs were taken with the pelvic limbs in the ventrodorsal, dorsoplantar, mediolateral and lateromedial recumbency. Thereafter, the material was fixed in a 10% solution of formaldehyde and dissected. The pelvic limb received its arterial supply from two main vessels, the ischiatic and external iliac arteries. The ischiatic artery presented to be the principal artery of pelvic limb in the caracara and great egret. Several branches arised from the ischiatic and external iliac arteries were described. No gender differences were observed in both species. The caracara and great egret showed arteries similar to those reported for the ostrich and domestic fowl. According to the results of this study, it is suggested that the caracara has a pelvic limb with more arterial branches and larger arterial diameter than the great egret, which is probably related to the specific behaviour of these birds, since the caracara is a bird that exercise more their pelvic limbs to capture its prey when compared with the great egret.
Topics: Angiography; Animals; Arteries; Birds; Brazil; Falconiformes; Feeding Behavior; Female; Hindlimb; Iliac Artery; Male; Popliteal Artery; Tibial Arteries
PubMed: 32537833
DOI: 10.1111/ahe.12585 -
The Laryngoscope Dec 2023Described herein is an innovative, minimally-invasive technique to harvest temporoparietal fascia flap used in implant-based ear reconstruction for children with...
Described herein is an innovative, minimally-invasive technique to harvest temporoparietal fascia flap used in implant-based ear reconstruction for children with microtia. This technique utilizes a never previously described application of intra-operative Indocyanine Green Angiography to optimize flap viability and minimizing the risk of facial nerve injury. Laryngoscope, 133:3615-3618, 2023.
Topics: Child; Humans; Indocyanine Green; Congenital Microtia; Plastic Surgery Procedures; Surgical Flaps; Angiography
PubMed: 37218680
DOI: 10.1002/lary.30759 -
Vascular Jun 2022Research in the field of lower extremity vascular disease has increased in popularity over the years. To adequately characterize and validate the effectiveness of...
OBJECTIVES
Research in the field of lower extremity vascular disease has increased in popularity over the years. To adequately characterize and validate the effectiveness of vascular interventions, in vivo experimentation in large animals is required. Thus, it is necessary to find a method to detect the shape and density of blood vessels in the lower extremities that can evaluate and verify the treatment measures' effectiveness and have high accuracy and repeatability. This study characterized factors that determined both the accuracy and overall value of digital subtraction angiography in lower limb arteriography using a canine animal model.
METHODS
Six beagle dogs were anesthetized and immobilized on the motorized table. The femoral artery was accessed using an indwelling needle. A bolus of contrast agent was injected into the access site, and digital subtraction angiography with bolus chase technology was used to collect contrast images for analysis. At the end of the procedure, the anesthetized dogs were euthanized using an overdose of potassium chloride. After confirming the euthanasia of the dogs, the cadavers were taken to the experimental animal center of Xinjiang Medical University and processed by qualified institutional personnel.
RESULTS
The final arteriographic images of the hind limbs from all six dogs were precise, and the branches of small vessels could be distinguished without any visible artifacts.
CONCLUSIONS
These results suggested that arteriography using digital subtraction angiography could reveal the shape and density of blood vessels in canine animal models. This method has great potential to significantly improve research related to limb ischemia due to its simple and reproducible results.
Topics: Angiography, Digital Subtraction; Animals; Dogs; Femoral Artery; Hindlimb; Humans; Ischemia; Lower Extremity
PubMed: 34080448
DOI: 10.1177/17085381211020927 -
RoFo : Fortschritte Auf Dem Gebiete Der... Feb 2020Peripheral vascular anomalies represent a rare disease with an underlying congenital mesenchymal and angiogenetic disorder. Vascular anomalies are subdivided into...
BACKGROUND
Peripheral vascular anomalies represent a rare disease with an underlying congenital mesenchymal and angiogenetic disorder. Vascular anomalies are subdivided into vascular tumors and vascular malformations. Both entities include characteristic features and flow dynamics. Symptoms can occur in infancy and adulthood. Vascular anomalies may be accompanied by characteristic clinical findings which facilitate disease classification. The role of periinterventional imaging is to confirm the clinically suspected diagnosis, taking into account the extent and location of the vascular anomaly for the purpose of treatment planning.
METHOD
In accordance with the International Society for the Study of Vascular Anomalies (ISSVA), vascular anomalies are mainly categorized as slow-flow and fast-flow lesions. Based on the diagnosis and flow dynamics of the vascular anomaly, the recommended periinterventional imaging is described, ranging from ultrasonography and plain radiography to dedicated ultrafast CT and MRI protocols, percutaneous phlebography and transcatheter angiography. Each vascular anomaly requires dedicated imaging. Differentiation between slow-flow and fast-flow vascular anomalies facilitates selection of the appropriate imaging modality or a combination of diagnostic tools.
RESULTS
Slow-flow congenital vascular anomalies mainly include venous and lymphatic or combined malformations. Ultrasound and MRI and especially MR-venography are essential for periinterventional imaging. Arteriovenous malformations are fast-flow vascular anomalies. They should be imaged with dedicated MR protocols, especially when extensive. CT with 4D perfusion imaging as well as time-resolved 3D MR-A allow multiplanar perfusion-based assessment of the multiple arterial inflow and venous drainage vessels of arterio-venous malformations. These imaging tools should be subject to intervention planning, as they can reduce procedure time significantly. Fast-flow vascular tumors like hemangiomas should be worked up with ultrasound, including color-coded duplex sonography, MRI and transcatheter angiography in case of a therapeutic approach. In combined malformation syndromes, radiological imaging has to be adapted according to the dominant underlying vessels and their flow dynamics.
CONCLUSION
Guide to evaluation of flow dynamics in peripheral vascular anomalies, involving vascular malformations and vascular tumors with the intention to facilitate selection of periinterventional imaging modalities and diagnostic and therapeutic approach to vascular anomalies.
KEY POINTS
· Peripheral vascular anomalies include vascular malformations and vascular tumors. Both entities represent a rare disease with an underlying congenital mesenchymal or angiogenetic disorder. · The role of periinterventional imaging is confirmation of the diagnosis by assessing the flow dynamics of the vascular anomaly. · Slow-flow congenital vascular anomalies include venous, lymphatic and venolymphatic malformations. Arteriovenous malformations are fast-flow vascular anomalies, whereas hemangiomas are fast-flow vascular tumors that are frequently associated with fast-flow arteriovenous shunts. The periinterventional imaging modalities of choice include dedicated MR protocols and CT with 4D perfusion imaging as well as invasive transcatheter angiography..
CITATION FORMAT
· Sadick M, Overhoff D, Baessler B et al. Peripheral Vascular Anomalies - Essentials in Periinterventional Imaging. Fortschr Röntgenstr 2020; 192: 150 - 162.
Topics: Angiography; Computed Tomography Angiography; Four-Dimensional Computed Tomography; Hemodynamics; Humans; Magnetic Resonance Angiography; Perfusion Imaging; Phlebography; Tomography, X-Ray Computed; Ultrasonography; Vascular Malformations
PubMed: 31622988
DOI: 10.1055/a-0998-4300 -
Vestnik Oftalmologii 2022This review of literature presents an assessment of circulatory disorders of the optic nerve and the retina in patients with optic neuropathy of different origin by... (Review)
Review
This review of literature presents an assessment of circulatory disorders of the optic nerve and the retina in patients with optic neuropathy of different origin by ultrasound and OCTA methods, outlines basic principles of analyzing the state of blood flow in the ocular vessels, and analyzes the results of Russian and foreign research on this topic.
Topics: Angiography; Fluorescein Angiography; Humans; Optic Disk; Optic Nerve Diseases; Tomography, Optical Coherence; Ultrasonography, Doppler
PubMed: 35801892
DOI: 10.17116/oftalma2022138031132 -
Journal of Neurointerventional Surgery Oct 2019Treated aneurysms must be followed over time to ensure durable occlusion, as more than 20% of endovascularly treated aneurysms recur. While digital subtraction... (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND
Treated aneurysms must be followed over time to ensure durable occlusion, as more than 20% of endovascularly treated aneurysms recur. While digital subtraction angiography (DSA) remains the gold standard, magnetic resonance angiography (MRA) is attractive as a non-invasive follow-up technique. Two different MRA techniques have traditionally been used: time-of-flight (TOF) and contrast-enhanced (CE) MRA. We analysed data from studies comparing MRA techniques with DSA for the follow-up of aneurysms undergoing endovascular treatment. Subgroup analysis of stent-assisted coiling (SAC) and flow diversion (FD) techniques was completed.
METHODS
Comprehensive searches using the Embase, PubMed, and Cochrane databases were performed and updated to November 2018. Pooled sensitivity and specificity were calculated using aneurysm occlusion status as defined by the Raymond-Roy occlusion grading scale.
RESULTS
The literature search yielded 1579 unique titles. Forty-three studies were included. For TOF-MRA, sensitivity and specificity of all aneurysms undergoing endovascular therapy were 88% and 94%, respectively. For CE-MRA, the sensitivity and specificity were 88% and 96%, respectively. For SAC and FD techniques, sensitivity and specificity of TOF-MRA were 86% and 95%, respectively. CE-MRA had sensitivity and specificity of 90% and 92%.
CONCLUSION
MRA is a reliable modality for the follow-up of aneurysms treated using endovascular techniques. While the data are limited, MRA techniques can also be used to reliably follow patients undergoing FD and SAC. However, clinical factors must be used to optimize follow-up regimens for individual patients.
Topics: Adult; Aged; Angiography, Digital Subtraction; Endovascular Procedures; Female; Follow-Up Studies; Humans; Intracranial Aneurysm; Magnetic Resonance Angiography; Middle Aged; Treatment Outcome
PubMed: 31048457
DOI: 10.1136/neurintsurg-2019-014936 -
BMC Cardiovascular Disorders Dec 2022Despite advances in endovascular techniques to treat acute limb ischemia (ALI), evaluation of clinical outcomes for revascularization remains challenging, especially the...
BACKGROUND
Despite advances in endovascular techniques to treat acute limb ischemia (ALI), evaluation of clinical outcomes for revascularization remains challenging, especially the accurate quantification of post-endovascular limb perfusion. This study aimed to investigate the accuracy and value of 2D perfusion angiography to evaluate endovascular intervention for ALI.
METHODS
A total of 47 patients with ALI were retrospectively analyzed. The transcutaneous oxygen partial pressure (TcPO2) was obtained using laser Doppler blood perfusion monitoring. The ankle-brachial index (ABI) and angiographic images were obtained before and after endovascular intervention. iFlow imaging was used to obtain color-coded images. Regions of interest (ROIs) at the femoral head, knee joint, and ankle joint were selected to obtain the time to peak (TTP). The differences in the TTP between the knee and femoral head regions (TTP difference in the knee area) and between the ankle and knee regions (TTP difference in the ankle area) were observed. The TTP, ABI, and TcPO2 between the complete response (CR), partial response (PR), no response (NR), and amputation (AM) groups were compared. The correlation between TTP changes in the ankle area (ΔTTP) and changes in ABI (ΔABI)/changes in TcPO2 (ΔTcPO2) was analyzed.
RESULTS
There was a significant increase in both TcPO2 and ABI compared with the pre-intervention values (27.75 ± 5.32 vs 40.92 ± 4.62, and 0.35 ± 0.16 vs 0.79 ± 0.15, respectively, all p < 0.01). The post-intervention TTP differences in the knee areas (5.12 ± 2.45 s) and ankle areas (6.93 ± 4.37 s) were significantly faster than pre-intervention TTP differences (7.03 ± 2.57 s and 10.66 ± 4.07 s, respectively, all p < 0.05). The post-operative TTP in the ankle area, post-operative TTP difference in the ankle area, and ΔTTP in the AM group were higher than the values in the CR and PR groups. The ΔTTP demonstrated strong correlation with ΔABI (r = -0.722, p < 0.01) and ΔTcPO2 (r = -0.734, p < 0.01).
CONCLUSIONS
2D perfusion angiography with enhanced visual and quantitative analysis exhibits great potential to evaluate the efficacy of endovascular intervention, and provides a quantitative and sensitive tool to evaluate post-endovascular limb perfusion for ALI patients.
Topics: Humans; Angiography; Ischemia; Perfusion; Retrospective Studies
PubMed: 36463099
DOI: 10.1186/s12872-022-02979-x