Impact of image reconstruction parameters when using 3D DSA reconstructions to measure intracranial aneurysms

2017 ◽  
Vol 10 (3) ◽  
pp. 285-289 ◽  
Author(s):  
Katrina L Ruedinger ◽  
David R Rutkowski ◽  
Sebastian Schafer ◽  
Alejandro Roldán-Alzate ◽  
Erick L Oberstar ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Hounsfield Unit ◽  
Ground Truth ◽  
Individual Case ◽  
Dome Height ◽  
Patient Specific ◽  
Analysis Tool ◽  
Accuracy Of Measurements ◽  
Image Characteristic

Background and purposeSafe and effective use of newly developed devices for aneurysm treatment requires the ability to make accurate measurements in the angiographic suite. Our purpose was to determine the parameters that optimize the geometric accuracy of three-dimensional (3D) vascular reconstructions.MethodsAn in vitro flow model consisting of a peristaltic pump, plastic tubing, and 3D printed patient-specific aneurysm models was used to simulate blood flow in an intracranial aneurysm. Flow rates were adjusted to match values reported in the literature for the internal carotid artery. 3D digital subtraction angiography acquisitions were obtained using a commercially available biplane angiographic system. Reconstructions were done using Edge Enhancement (EE) or Hounsfield Unit (HU) kernels and a Normal or Smooth image characteristic. Reconstructed images were analyzed using the vendor's aneurysm analysis tool. Ground truth measurements were derived from metrological scans of the models with a microCT. Aneurysm volume, surface area, dome height, minimum and maximum ostium diameter were determined for the five models.ResultsIn all cases, measurements made with the EE kernel most closely matched ground truth values. Differences in values derived from reconstructions displayed with Smooth or Normal image characteristics were small and had only little impact on the geometric parameters considered.ConclusionsReconstruction parameters impact the accuracy of measurements made using the aneurysm analysis tool of a commercially available angiographic system. Absolute differences between measurements made using reconstruction parameters determined as optimal in this study were, overall, very small. The significance of these differences, if any, will depend on the details of each individual case.

scholarly journals 3D printed patient-specific aortic root models with internal sensors for minimally invasive applications

2020 ◽  
Vol 6 (35) ◽  
pp. eabb4641 ◽  
Author(s):  
Ghazaleh Haghiashtiani ◽  
Kaiyan Qiu ◽  
Jorge D. Zhingre Sanchez ◽  
Zachary J. Fuenning ◽  
Priya Nair ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
Aortic Root ◽  
Three Dimensional ◽  
Sensor Arrays ◽  
Invasive Procedure ◽  
Patient Specific ◽  
Anatomical Site ◽  
Transcatheter Aortic Valve ◽  
Critical Regions

Minimally invasive surgeries have numerous advantages, yet complications may arise from limited knowledge about the anatomical site targeted for the delivery of therapy. Transcatheter aortic valve replacement (TAVR) is a minimally invasive procedure for treating aortic stenosis. Here, we demonstrate multimaterial three-dimensional printing of patient-specific soft aortic root models with internally integrated electronic sensor arrays that can augment testing for TAVR preprocedural planning. We evaluated the efficacies of the models by comparing their geometric fidelities with postoperative data from patients, as well as their in vitro hemodynamic performances in cases with and without leaflet calcifications. Furthermore, we demonstrated that internal sensor arrays can facilitate the optimization of bioprosthetic valve selections and in vitro placements via mapping of the pressures applied on the critical regions of the aortic anatomies. These models may pave exciting avenues for mitigating the risks of postoperative complications and facilitating the development of next-generation medical devices.

scholarly journals Patient-Specific Quality Assurance Using a 3D-Printed Chest Phantom for Intraoperative Radiotherapy in Breast Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Yeonho Choi ◽  
Ik Jae Lee ◽  
Kwangwoo Park ◽  
Kyung Ran Park ◽  
Yeona Cho ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Soft Tissue ◽  
Three Dimensional ◽  
Intraoperative Radiotherapy ◽  
Hounsfield Unit ◽  
Patient Specific ◽  
Depth Dose ◽  
Dose Comparison ◽  
3D Printed ◽  
The Mean

This study aims to confirm the usefulness of patient-specific quality assurance (PSQA) using three-dimensional (3D)-printed phantoms in ensuring the stability of IORT and the precision of the treatment administered. In this study, five patient-specific chest phantoms were fabricated using a 3D printer such that they were dosimetrically equivalent to the chests of actual patients in terms of organ density and shape around the given target, where a spherical applicator was inserted for breast IORT treatment via the INTRABEAM™ system. Models of lungs and soft tissue were fabricated by applying infill ratios corresponding to the mean Hounsfield unit (HU) values calculated from CT scans of the patients. The two models were then assembled into one. A 3D-printed water-equivalent phantom was also fabricated to verify the vendor-provided depth dose curve. Pieces of an EBT3 film were inserted into the 3D-printed customized phantoms to measure the doses. A 10 Gy prescription dose based on the surface of the spherical applicator was delivered and measured through EBT3 films parallel and perpendicular to the axis of the beam. The shapes of the phantoms, CT values, and absorbed doses were compared between the expected and printed ones. The morphological agreement among the five patient-specific 3D chest phantoms was assessed. The mean differences in terms of HU between the patients and the phantoms was 2.2 HU for soft tissue and −26.2 HU for the lungs. The dose irradiated on the surface of the spherical applicator yielded a percent error of −2.16% ± 3.91% between the measured and prescribed doses. In a depth dose comparison using a 3D-printed water phantom, the uncertainty in the measurements based on the EBT3 film decreased as the depth increased beyond 5 mm, and a good agreement in terms of the absolute dose was noted between the EBT3 film and the vendor data. These results demonstrate the applicability of the 3D-printed chest phantom for PSQA in breast IORT. This enhanced precision offers new opportunities for advancements in IORT.

scholarly journals Patient-Specific Aortic Phantom With Tunable Compliance

2019 ◽  
Vol 2 (4) ◽  
Author(s):  
Antonio Gallarello ◽  
Andrea Palombi ◽  
Giacomo Annio ◽  
Shervanthi Homer-Vanniasinkam ◽  
Elena De Momi ◽  
...  
Keyword(s):  
Aortic Arch ◽  
Computational Models ◽  
Three Dimensional ◽  
Complex Interventions ◽  
Patient Specific ◽  
Arch Model ◽  
Magnetic Resonance Imaging Mri ◽  
Variable Wall ◽  
Silicone Model

Abstract Validation of computational models using in vitro phantoms is a nontrivial task, especially in the replication of the mechanical properties of the vessel walls, which varies with age and pathophysiological state. In this paper, we present a novel aortic phantom reconstructed from patient-specific data with variable wall compliance that can be tuned without recreating the phantom. The three-dimensional (3D) geometry of an aortic arch was retrieved from a computed tomography angiography scan. A rubber-like silicone phantom was manufactured and connected to a compliance chamber in order to tune its compliance. A lumped resistance was also coupled with the system. The compliance of the aortic arch model was validated using the Young's modulus and characterized further with respect to clinically relevant indicators. The silicone model demonstrates that compliance can be finely tuned with this system under pulsatile flow conditions. The phantom replicated values of compliance in the physiological range. Both, the pressure curves and the asymmetrical behavior of the expansion, are in agreement with the literature. This novel design approach allows obtaining for the first time a phantom with tunable compliance. Vascular phantoms designed and developed with the methodology proposed in this paper have high potential to be used in diverse conditions. Applications include training of physicians, pre-operative trials for complex interventions, testing of medical devices for cardiovascular diseases (CVDs), and comparative Magnetic-resonance-imaging (MRI)-based computational studies.

Investigations for Wax Coated 3D Printed Hybrid Patterns for Partial Dentures

2019 ◽  
Author(s):  
Kamaljit Singh Boparai ◽  
Gurpartap Singh ◽  
Rupinder Singh ◽  
Sarabjit Singh
Keyword(s):  
Fused Deposition Modeling ◽  
Three Dimensional ◽  
Surface Hardness ◽  
Dimensional Accuracy ◽  
Acrylonitrile Butadiene Styrene ◽  
Processing Technique ◽  
Patient Specific ◽  
Fused Deposition ◽  
3D Printed

Abstract In this work, 3D printed master patterns of acrylonitrile butadiene styrene (ABS) thermoplastic material have been used for the preparation of Ni-Cr based functional prototypes as partial dentures (PD). The study started with patient specific three dimensional (3D), CAD data (fetched through scanning). This data was used for preparation of .STL file for printing of master patterns on fused deposition modeling (FDM) setup. The 3D printed master patterns were further wax coated to reduce the surface irregularities (as cost effective post processing technique). The hybrid patterns were subjected to investment casting for the preparation of Ni-Cr based PD. The finally prepared functional prototypes as PD were optimized for dimensional accuracy, surface finish and surface hardness as responses. The results are visualized and supported by photomicrographs and in-vitro analysis.

Living the heart in three dimensions: applications of 3D printing in CHD

2019 ◽  
Vol 29 (06) ◽  
pp. 733-743 ◽  
Author(s):  
Mari Nieves Velasco Forte ◽  
Tarique Hussain ◽  
Arno Roest ◽  
Gorka Gomez ◽  
Monique Jongbloed ◽  
...  
Keyword(s):  
3D Printing ◽  
Heart Surgery ◽  
Wide Spectrum ◽  
Three Dimensional ◽  
Structural Heart Disease ◽  
Medical Personnel ◽  
Three Dimensions ◽  
Patient Specific ◽  
3D Printed

AbstractAdvances in biomedical engineering have led to three-dimensional (3D)-printed models being used for a broad range of different applications. Teaching medical personnel, communicating with patients and relatives, planning complex heart surgery, or designing new techniques for repair of CHD via cardiac catheterisation are now options available using patient-specific 3D-printed models. The management of CHD can be challenging owing to the wide spectrum of morphological conditions and the differences between patients. Direct visualisation and manipulation of the patients’ individual anatomy has opened new horizons in personalised treatment, providing the possibility of performing the whole procedure in vitro beforehand, thus anticipating complications and possible outcomes. In this review, we discuss the workflow to implement 3D printing in clinical practice, the imaging modalities used for anatomical segmentation, the applications of this emerging technique in patients with structural heart disease, and its limitations and future directions.

Patient-derived organoids for personalized drug screening in intrahepatic cholangiocarcinoma.

2020 ◽  
Vol 38 (4_suppl) ◽  
pp. 581-581
Author(s):  
Ricardo J. Antonia ◽  
Kan Toriguchi ◽  
Eveliina Karelehto ◽  
Dania Annuar ◽  
Luika Timmerman ◽  
...  
Keyword(s):  
High Throughput ◽  
Drug Screening ◽  
Intrahepatic Cholangiocarcinoma ◽  
Three Dimensional ◽  
Small Samples ◽  
Patient Specific ◽  
Mtor Inhibition ◽  
Drug Responses

581 Background: Despite standard treatment with gemcitabine and cisplatin, median survival for unresectable Intrahepatic Cholangiocarcinoma (ICC) is < 1 year. Clearly, novel therapeutic strategies are urgently needed. The paucity of targetable mutations in ICC and the as yet unproven benefit of genetically targeted drugs led us to ask whether a reliable clinical benefit may be revealed by patient-specific therapeutic testing in novel models of ICC. Here we describe our ability to establish patient-derived three-dimensional organoid cultures (PDO) that enable individualized identification of active single agents or drug combinations in surrogate models of ICC. Methods: To model patient-specific drug responses, we used the freshly resected ICCs from small samples of single patient tumors to generate PDXs and PDOs, small spheroidal clusters of tumor cells grown in vitro. We have employed a high-throughput drug screening platform using AI-enhanced robotics (Yamaha Motor Corporation) to identify and distribute single, uniformly sized PDOs into 384-well ultra-low adherent plates. This is coupled with a TECAN D300e drug dispenser that rapidly delivers nanoliter volumes of a 34-drug panel, thereby facilitating rapid, reliable drug response analyses. Results: Our data show that PDOs retain characteristic genomic and histological features of the patients’ tumors. Drug responses were specific to each patient tumor, but PDOs from all patients responded to a greater or lesser degree to mTOR inhibition, suggesting that this pathway is important in ICC. The responses of PDO to the mTOR inhibitor Sapanisertib (INK128), was recapitulated in the same patient’s PDX. Further, INK128 was synergistic with gemcitabine in patient 970 PDOs as well as in vivo in PDX also from patient 970. Conclusions: As it is believed that PDX can predict patient responses to drugs, our results suggest that PDO may also predict patient drug responses. The establishment of PDO may allow economical patient-specific, high throughput drug screens that could ultimately inform clinical practice. [Table: see text]

scholarly journals Designing Hydrogel-Based Bone-On-Chips for Personalized Medicine

2021 ◽  
Vol 11 (10) ◽  
pp. 4495
Author(s):  
Gabriele Nasello ◽  
Mar Cóndor ◽  
Ted Vaughan ◽  
Jessica Schiavi
Keyword(s):  
Three Dimensional ◽  
In Vitro Models ◽  
Patient Specific ◽  
Specific Situation ◽  
Culture Chamber ◽  
Definition Of ◽  
And Function ◽  
Tissue Matrix ◽  
Hematopoietic Niche

The recent development of bone-on-chips (BOCs) holds the main advantage of requiring a low quantity of cells and material, compared to traditional In Vitro models. By incorporating hydrogels within BOCs, the culture system moved to a three dimensional culture environment for cells which is more representative of bone tissue matrix and function. The fundamental components of hydrogel-based BOCs, namely the cellular sources, the hydrogel and the culture chamber, have been tuned to mimic the hematopoietic niche in the bone aspirate marrow, cancer bone metastasis and osteo/chondrogenic differentiation. In this review, we examine the entire process of developing hydrogel-based BOCs to model In Vitro a patient specific situation. First, we provide bone biological understanding for BOCs design and then how hydrogel structural and mechanical properties can be tuned to meet those requirements. This is followed by a review on hydrogel-based BOCs, developed in the last 10 years, in terms of culture chamber design, hydrogel and cell source used. Finally, we provide guidelines for the definition of personalized pathological and physiological bone microenvironments. This review covers the information on bone, hydrogel and BOC that are required to develop personalized therapies for bone disease, by recreating clinically relevant scenarii in miniaturized devices.

scholarly journals Enhanced Neuronal Activity and Asynchronous Calcium Transients Revealed in a 3D Organoid Model of Alzheimer’s Disease

2020 ◽  
Author(s):  
Juan Yin ◽  
Antonius M. VanDongen
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neurodegenerative Disorders ◽  
Three Dimensional ◽  
Calcium Transients ◽  
Network Activity ◽  
Patient Specific ◽  
Neuronal Network Activity ◽  
Model Of Alzheimer’S Disease

AbstractAdvances in the development of three-dimensional (3D) brain organoids maintained in vitro have provided excellent opportunities to study brain development and neurodegenerative disorders, including Alzheimer’s disease (AD). However, there remains a need to generate AD organoids bearing patient-specific genomic backgrounds that can functionally recapitulate key features observed in the AD patient’s brain. To address this need, we successfully generated cerebral organoids from human pluripotent stem cells (hPSCs) derived from a familial AD patient with a mutation in presenilin 2 (PSEN2). An isogenic control hPSC line was generated using CRISPR-Cas9 technology. Both organoids were characterized by analysing their morphology, Aβ42/Aβ40 ratio and functional neuronal network activity. It was found that AD organoids had a higher Aβ42/Aβ40 ratio, asynchronous calcium transients and enhanced neuronal hyperactivity, successfully recapitulating some aspects of AD pathology. Therefore, our study presents a promising organoid-based biosystem for the study of the pathophysiology of AD and a platform for drug development for neurodegenerative disorders.

scholarly journals 3D-printed saw guides for lower arm osteotomy, a comparison between a synthetic CT and CT-based workflow

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Koen Willemsen ◽  
Mirte H. M. Ketel ◽  
Frank Zijlstra ◽  
Mateusz C. Florkow ◽  
Ruurd J. A. Kuiper ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Ground Truth ◽  
Image Resolution ◽  
Patient Specific ◽  
Surface Model ◽  
Micro Ct ◽  
Generative Adversarial Network ◽  
Surface Models ◽  
3D Printed ◽  
Synthetic Ct

Abstract Background Three-dimensional (3D)-printed saw guides are frequently used to optimize osteotomy results and are usually designed based on computed tomography (CT), despite the radiation burden, as radiation-less alternatives like magnetic resonance imaging (MRI) have inferior bone visualization capabilities. This study investigated the usability of MR-based synthetic-CT (sCT), a novel radiation-less bone visualization technique for 3D planning and design of patient-specific saw guides. Methods Eight human cadaveric lower arms (mean age: 78y) received MRI and CT scans as well as high-resolution micro-CT. From the MRI scans, sCT were generated using a conditional generative adversarial network. Digital 3D bone surface models based on the sCT and general CT were compared to the surface model from the micro-CT that was used as ground truth for image resolution. From both the sCT and CT digital bone models saw guides were designed and 3D-printed in nylon for one proximal and one distal bone position for each radius and ulna. Six blinded observers placed these saw guides as accurately as possible on dissected bones. The position of each guide was assessed by optical 3D-scanning of each bone with positioned saw guide and compared to the preplanning. Eight placement errors were evaluated: three translational errors (along each axis), three rotational errors (around each axis), a total translation (∆T) and a total rotation error (∆R). Results Surface models derived from micro-CT were on average smaller than sCT and CT-based models with average differences of 0.27 ± 0.30 mm for sCT and 0.24 ± 0.12 mm for CT. No statistically significant positioning differences on the bones were found between sCT- and CT-based saw guides for any axis specific translational or rotational errors nor between the ∆T (p = .284) and ∆R (p = .216). On Bland-Altman plots, the ∆T and ∆R limits of agreement (LoA) were within the inter-observer variability LoA. Conclusions This research showed a similar error for sCT and CT digital surface models when comparing to ground truth micro-CT models. Additionally, the saw guide study showed equivalent CT- and sCT-based saw guide placement errors. Therefore, MRI-based synthetic CT is a promising radiation-less alternative to CT for the creation of patient-specific osteotomy surgical saw guides.

Bioprinting stem cells: building physiological tissues one cell at a time

2020 ◽  
Vol 319 (3) ◽  
pp. C465-C480 ◽  
Author(s):  
Chiara Scognamiglio ◽  
Alessandro Soloperto ◽  
Giancarlo Ruocco ◽  
Gianluca Cidonio
Keyword(s):  
Stem Cells ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
3D Models ◽  
In Vitro Models ◽  
Three Dimensions ◽  
Patient Specific ◽  
Regeneration Ability ◽  
3D Print

Bioprinting aims to direct the spatial arrangement in three dimensions of cells, biomaterials, and growth factors. The biofabrication of clinically relevant constructs for the repair or modeling of either diseased or damaged tissues is rapidly advancing, resulting in the ability to three-dimensional (3D) print biomimetic platforms which imitate a large number of tissues in the human body. Primary tissue-specific cells are typically isolated from patients and used for the fabrication of 3D models for drug screening or tissue repair purposes. However, the lack of resilience of these platforms, due to the difficulties in harnessing, processing, and implanting patient-specific cells can limit regeneration ability. The printing of stem cells obviates these hurdles, producing functional in vitro models or implantable constructs. Advancements in biomaterial science are helping the development of inks suitable for the encapsulation and the printing of stem cells, promoting their functional growth and differentiation. This review specifically aims to investigate the most recent studies exploring innovative and functional approaches for the printing of 3D constructs to model disease or repair damaged tissues. Key concepts in tissue physiology are highlighted, reporting stem cell applications in biofabrication. Bioprinting technologies and biomaterial inks are listed and analyzed, including recent advancements in biomaterial design for bioprinting applications, commenting on the influence of biomaterial inks on the encapsulated stem cells. Ultimately, most recent successful efforts and clinical potentials for the manufacturing of functional physiological tissue substitutes are reported here, with a major focus on specific tissues, such as vasculature, heart, lung and airways, liver, bone and muscle.

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