No funding was received for this work.

1. Repositioning of the jaws
NOTE: This section is performed using the imaging software (i.e., Dolphin).
<ol>
	<li>Load the facial bones CT image DICOM files of the patient (Figure 1A) into the software by selecting the 3D button on the left and clicking Import New DICOM (Supplemental Figure 1). Enter the 3D editing mode by clicking 3D | Edit.</li>
	<li>Orient the 3D image using the orientation button on the left. Create a panoramic image using the build X-rays button on the left (Supplemental Figure 2).</li>
	<li>Go to Tools | Orthognathic Surgical Planning | Start New Workup.</li>
	<li>Position the segments in the panoramic image. Crop each segment to contain the area of the corresponding bone. 
	NOTE: The cleaning stage is useful when, for accuracy, a scanned dental arch and a CT scan are superimposed to create a wafer. This is not indicated in a &#8220;waferless&#8221; surgery as presented here and thus at this stage one can clean CT imperfections if they exist.</li>
	<li>Choose the appropriate osteotomy for the patient on the left pan under osteotomies (such as LeFort I, sagittal split, etc.). Mark the exact location of the osteotomy lines by moving the yellow circles (Supplemental Figure 3). 
	NOTE: It is extremely important to note the root apexes of the teeth as the location of the osteotomy decided here will be the one performed later based on the surgical guides. Always avoid the roots and maintain a 5 mm distance.</li>
	<li>Mark different landmarks by left clicking on the right location for each suggested landmark. 
	NOTE: This is important for measurements and movement purposes in the next stages.</li>
	<li>Perform movements of bone segments. Drag the bone to the right location, or for accuracy, right click and choose Input Movements Using Keyboard.</li>
	<li>In order to track the movement of key landmarks, press Treat Options Button on the left and choose Show Landmark Offset and Measurement Tables. 
	NOTE: In the next tab the pre and post virtually planned operation can be observed (Supplemental Figure 4).</li>
	<li>Export the stl files of the two different positions of bone segments, one in the pre-operative stage and one in the post-operative stage, using the slide bar on the left and the Export Segments in stl button on the left.</li>
</ol>
2. Preparation of patient-specific fixation plates and surgical guides
NOTE: This section is performed using the 3D design software (i.e., Geomagic Freeform).
<ol>
	<li>Click File | Import Model (Supplemental Figure 5A) to import the stl files obtained from step 1.9 showing the position of the upper jaw and midface following the osteotomy but prior to the repositioning in the final position.</li>
	<li>Start with planning the patient-specific fixation plates in the final position of the upper jaw. In the tool palette on the left under the Planes category, select Create Plane (Supplemental Figure 6A). Here the initial design of the plates will be performed. Manually move the plane parallel to the bone where the plate will be placed.</li>
	<li>Under the Sketch category (Supplemental Figure 6B), choose a circle shape and create circles with a size appropriate for the screws to be used later. Create a second circle around the previous one 3 mm larger in diameter to outline the fixation plate. 
	NOTE: The size of the circles is determined based on the fixation sets used in each institute. The circles are placed above and below the planned surgical osteotomy (decided already in section 1).</li>
	<li>Project the design from the plane to the bone. Under the Curves category (Supplemental Figure 7), use the project sketch tool and choose the circles that will be transferred from the plane to the bone.</li>
	<li>To connect the outer circles for the outer border plate design, choose under the Curves category the split tool and define the part of the circle that will be removed to allow for a connection to the adjacent circles. Using the select option, choose the defined part of the circle and delete it. Under the Curves category, use the draw curve tool and connect the outer circles to create a continuous outer shape of the patient-specific plate.</li>
	<li>Before creating the fixation plate, duplicate the upper jaw by right clicking and selecting Duplicate from the object list (Supplemental Figure 7A). This will allow the use of the Boolean tool in the next stages to create the fixation plate.</li>
	<li>Under the Detail Clay category, use the emboss with curve tool. This creates the volume of the fixation plate based on the curves previously projected. Choose the outer shape curve and then place the circle-shaped cursor inside and on the surface of the shaped plate (note that the cursor should be placed on the side to be embossed). At the bottom, choose the parameters of the function, mainly the Distance option that controls the thickness of the future fixation plate.</li>
	<li>Separate the plate from the upper jaw. At this stage the Boolean option is performed. Choose the original upper jaw, right click from the object list and click Boolean | Remove from | Upper Jaw with Plate.</li>
	<li>To create the holes for the screws, either draw the screws/scan them and then use the Boolean option or use the SubD tool. Under the SubD Surfaces category (Supplemental Figure 8), use the wire cut SubD tool to create rods perpendicular to the plate in the size of desired holes, which is performed based on the circles created in step 2.3 originating from the perpendicular plane.</li>
	<li>Next, subtract the rods from the plate using the Boolean | Remove from technique. 
	NOTE: At this stage the final fixation plate is ready (Supplemental Figure 9). Appropriate surgical guides need to be planned for the osteotomy in order for the plates to fit perfectly.</li>
	<li>To create the guides, reposition the upper jaw to its original location but with the screw holes marked in the bone according to the fixation plate created in the final position of the jaw (note the holes in the midface do not change position as the midface stays in the same position).
	<ol>
		<li>To perform this, reposition the jaw with the curves for the holes used for the final fixation plate to the original location of the jaw prior to the movement. Under the Select/Move Clay category, use the Register Pieces option. choose the Source (upper jaw post movement) and the Target (upper jaw and midface prior to the movement). Use a large number of fixed points on both objects for accuracy in the repositioning.</li>
	</ol>
	</li>
	<li>Based on newly positioned holes create the surgical guides in a similar way as described for the fixation plates (steps 2.3&#8722;2.10).</li>
</ol>

<ol>
	<li>Hull, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Apparatus for production of three-dmensonal objects by stereo thography. , (1986).</li><li>Shilo, D., Emodi, O., Blanc, O., Noy, D., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Printing+the+Future-Updates+in+3D+Printing+for+Surgical+Applications.">Printing the Future-Updates in 3D Printing for Surgical Applications.</a> Rambam Maimonides Medical Journal. 9 (3), 20 (2018).</li><li>Emodi, O., Shilo, D., Israel, Y., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+planning+and+printing+of+guides+and+templates+for+reconstruction+of+the+mandibular+ramus+and+condyle+using+autogenous+costochondral+grafts.">Three-dimensional planning and printing of guides and templates for reconstruction of the mandibular ramus and condyle using autogenous costochondral grafts.</a> British Journal of Oral and Maxillofacial Surgery. 55 (1), 102-104 (2017).</li><li>Leiser, Y., Shilo, D., Wolff, A., Rachmiel, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+reconstruction+in+mandibular+avulsion+injuries.">Functional reconstruction in mandibular avulsion injuries.</a> Journal of Craniofacial Surgery. 27 (8), 2113-2116 (2016).</li><li>Rachmiel, A., Shilo, D., Blanc, O., Emodi, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reconstruction+of+complex+mandibular+defects+using+integrated+dental+custom-made+titanium+implants.">Reconstruction of complex mandibular defects using integrated dental custom-made titanium implants.</a> British Journal of Oral and Maxillofacial Surgery. 55 (4), 425-427 (2017).</li><li>Lauren, M., McIntyre, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+computer-assisted+method+for+design+and+fabrication+of+occlusal+splints.">A new computer-assisted method for design and fabrication of occlusal splints.</a> American Journal of Orthodontics and Dentofacial Orthopedics. 133 (4), 130-135 (2008).</li><li>Song, K. -. G., Baek, S. -. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+the+accuracy+of+the+three-dimensional+virtual+method+and+the+conventional+manual+method+for+model+surgery+and+intermediate+wafer+fabrication.">Comparison of the accuracy of the three-dimensional virtual method and the conventional manual method for model surgery and intermediate wafer fabrication.</a> Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology. 107 (1), 13-21 (2009).</li><li>Mazzoni, S., Bianchi, A., Schiariti, G., Badiali, G., Marchetti, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computer-aided+design+and+computer-aided+manufacturing+cutting+guides+and+customized+titanium+plates+are+useful+in+upper+maxilla+waferless+repositioning.">Computer-aided design and computer-aided manufacturing cutting guides and customized titanium plates are useful in upper maxilla waferless repositioning.</a> Journal of Oral and Maxillofacial Surgery. 73 (4), 701-707 (2015).</li><li>Hanafy, M., Akoush, Y., Abou-ElFetouh, A., Mounir, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+of+orthognathic+digital+plan+transfer+using+patient-specific+cutting+guides+and+osteosynthesis+versus+mixed+analogue-digitally+planned+surgery:+a+randomized+controlled+clinical+trial.">Precision of orthognathic digital plan transfer using patient-specific cutting guides and osteosynthesis versus mixed analogue-digitally planned surgery: a randomized controlled clinical trial.</a> International Journal of Oral and Maxillofacial Surgery. 49 (1), 62-68 (2019).</li><li>Tack, P., Victor, J., Gemmel, P., Annemans, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D-printing+techniques+in+a+medical+setting:+a+systematic+literature+review.">3D-printing techniques in a medical setting: a systematic literature review.</a> Biomedical Engineering Online. 15 (1), 115 (2016).</li></ol>

The authors have nothing to disclose.

3D planning and printing is one of the most rapidly evolving methods in the surgical field. It is not only a promising tool for the future, but a practical tool used nowadays for highly accurate surgical results and patient-specific solutions. It allows for highly accurate results and reduces the dependency on the surgeon&#8217;s experience10. It solves many of the disadvantages of previous old fashion surgical methods, but the costs delay the full implementation of the method10<...

3D printing is an additive method based on gradual placement of layers from different materials, thus creating 3D objects. It was originally developed for rapid prototyping and was introduced in 1984 by Charles Hull, who is considered the inventor of the stereolithography method based on solidifying layers of photopolymer resin1. Technological advancements in virtual planning of surgeries and planning and printing of patient-specific implants are constantly evolving. Innovations arise both in the field of computer assisted design (CAD) software and in 3D printing technologies2. Simultaneous to developments in technology, the software and printers become more user-friendly. This shortens the time required for planning and printing and allows the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates in a field that was exclusively an engineer&#8217;s &#8220;playground&#8221;. These developments also allow for surgeons and engineers to introduce new applications and designs of patient-specific implants3,4,5.
One of these applications is 3D planning of orthognathic surgeries followed by 3D planning and printing of surgical guides and patient-specific fixation plates. Historically, orthognathic surgeries were planned using articulators. A facebow was used to register the relationship of the upper jaw to the temporomandibular joint thus positioning the patient&#8217;s casts in the articulator. Later, the surgical movements were performed on the casts and an acrylic wafer was prepared to help with proper positioning of the jaws during surgery. This method was used for many years and is still used nowadays by most, but the utilization of cone beam computed tomography (CT) together with intra-oral scanners and CAD software allowed for accurate planning, sparing the need for facebows or casts and moving towards creation of digitally planned wafers6. This method reduced the inaccuracy of manual manipulation and measurements but still had flaws including using the instable lower jaw as a reference point for positioning the upper jaw and lack of control over the vertical positioning of the upper jaw7. Thus, a new method was introduced. This method is called the &#8220;waferless&#8221; surgery and is based on repositioning of the jaws anatomically using surgical cutting guides and patient-specific fixation titanium plates8. This method resolves the disadvantages of the digital wafer method described before. We will describe this method, which allows the surgeon complete freedom in planning these surgeries in a patient-specific manner, with minimal possible errors and inaccuracies. This method allows for a &#8220;waferless&#8221; surgery, which means there is no need for using the opposed jaw as reference for repositioning the bones, thus decreasing the inaccuracies derived from this reliance9.

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	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dolphin imaging software</td>
			<td style="width:207px;">Dolphin Imaging Systems LLC (Patterson Dental Supply, Inc)</td>
			<td style="width:161px;"></td>
			<td style="width:167px;">3D analysis and virtual planning of orthognathic surgeries</td>
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			<td height="21" style="height:21px;width:216px;">Geomagic Freeform</td>
			<td style="width:207px;">3D systems</td>
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			<td>Sculpted Engineering Design</td>
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</table>

treatment of facial deformities using 3d planning and printing of patient-specific implants

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve better results, even in the less experienced hand, or continue without it. As technology develops and becomes more user-friendly, we believe it is time to allow the surgeon the option to plan his/her operations and create his/her own patient-specific surgical guides and fixation plates allowing him full control over the process. We present here a protocol for 3D planning of the operation followed by 3D planning and printing of surgical guides and patient-specific fixation implants. During this process we use two commercial computer-assisted design (CAD) software. We also use a fused deposition&#160;modeling printer for the surgical guides and a selective laser sintering printer for the titanium patient-specific fixation implants. The process includes computed tomography (CT) imaging acquisition, 3D segmentation of the skull and facial bones from the CT, 3D planning of the operations, 3D planning of patient-specific fixation implant according to the final position of the bones, 3D planning of surgical guides for performing an accurate osteotomy and preparing the bone for the fixation plates, and 3D printing of the surgical guides and the patient-specific fixation plates. The advantages of the method include full control over the surgery, planned osteotomies and fixation plates, significant reduction in price, reduction in operation duration, superior performance and highly accurate results. Limitations include the need to master the CAD programs.

To observe the clinical use of the method, we present a case of a 23 year old female. She suffered from condylar hyperplasia at a younger age in the right condyle resulting in asymmetry of both jaws. Figure 1A shows the retrognathic upper jaw and prognathic lower jaw exhibiting the discrepancies between the jaws. In the frontal view, the severe asymmetry can be observed as detailed using the yellow and red lines. Using the imaging software (Supplemental Figure 1), a surgical...

Watch this Scientific Journal Video about Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants at JoVE.com

Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Technological advancements in surgical planning and patient-specific implants are constantly evolving. One can either adopt the technology to achieve ...

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7.1K Views.  Rambam Medical Care Center. As technology develops and becomes more user-friendly, planning of operations and patient-specific surgical guides and fixation plates should be performed by the surgeon. We present a protocol for 3D planning of orthognathic skeletal movements and 3D planning and printing of patient-specific fixation plates and surgical guides.

Video: Treatment of Facial Deformities using 3D Planning and Printing of Patient-Specific Implants

A Pipeline for 3D Multimodality Image Integration and Computer-assisted Planning in Epilepsy Surgery

Epilepsy surgery is challenging and the use of 3D multimodality image integration (3DMMI) to aid presurgical planning is well-established. Multimodality image integration can be technically demanding, and is underutilised in clinical practice. We have developed a single software platform for image integration, 3D visualization and surgical planning. Here, our pipeline is described in step-by-step fashion, starting with image acquisition, proceeding through image co-registration, manual segmentation, brain and vessel extraction, 3D visualization and manual planning of stereoEEG (SEEG) implantations. With dissemination of the software this pipeline can be reproduced in other centres, allowing other groups to benefit from 3DMMI. We also describe the use of an automated, multi-trajectory planner to generate stereoEEG implantation plans. Preliminary studies suggest this is a rapid, safe and efficacious adjunct for planning SEEG implantations. Finally, a simple solution for the export of plans and models to commercial neuronavigation systems for implementation of plans in the operating theater is described. This software is a valuable tool that can support clinical decision making throughout the epilepsy surgery pathway.

We describe the steps to use our custom designed software for image integration, visualization and planning in epilepsy surgery.

Epilepsy surgery is challenging and the use of 3D multimodality image integration (3DMMI) to aid presurgical planning is well-established. Multimodality ...

Radiation Planning Assistant - A Streamlined, Fully Automated Radiotherapy Treatment Planning System

The Radiation Planning Assistant (RPA) is a system developed for the fully automated creation of radiotherapy treatment plans, including volume-modulated arc therapy (VMAT) plans for patients with head/neck cancer and 4-field box plans for patients with cervical cancer. It is a combination of specially developed in-house software that uses an application programming interface to communicate with a commercial radiotherapy treatment planning system. It also interfaces with a commercial secondary dose verification software. The necessary inputs to the system are a Treatment Plan Order, approved by the radiation oncologist, and a simulation computed tomography (CT) image, approved by the radiographer. The RPA then generates a complete radiotherapy treatment plan. For the cervical cancer treatment plans, no additional user intervention is necessary until the plan is complete. For head/neck treatment plans, after the normal tissue and some of the target structures are automatically delineated on the CT image, the radiation oncologist must review the contours, making edits if necessary. They also delineate the gross tumor volume. The RPA then completes the treatment planning process, creating a VMAT plan. Finally, the completed plan must be reviewed by qualified clinical staff.

Radiation therapy is a highly complex cancer treatment that requires multiple specialists to create a treatment plan and provide quality assurance (QA) prior to delivery to a patient. This protocol describes the use of a fully automated system, the Radiation Planning Assistant (RPA), to create high-quality radiation treatment plans.

The Radiation Planning Assistant (RPA) is a system developed for the fully automated creation of radiotherapy treatment plans, including volume-modulated ...

Multicolor 3D Printing of Complex Intracranial Tumors in Neurosurgery

Three-dimensional (3D) printing technologies offer the possibility of visualizing patient-specific pathologies in a physical model of correct dimensions. The model can be used for planning and simulating critical steps of a surgical approach. Therefore, it is important that anatomical structures such as blood vessels inside a tumor can be printed to be colored not only on their surface, but throughout their whole volume. During simulation this allows for the removal of certain parts (e.g., with a high-speed drill) and revealing internally located structures of a different color. Thus, diagnostic information from various imaging modalities (e.g., CT, MRI) can be combined in a single compact and tangible object.
However, preparation and printing of such a fully colored anatomical model remains a difficult task. Therefore, a step-by-step guide is provided, demonstrating the fusion of different cross-sectional imaging data sets, segmentation of anatomical structures, and creation of a virtual model. In a second step the virtual model is printed with volumetrically colored anatomical structures using a plaster-based color 3D binder jetting technique. This method allows highly accurate reproduction of patient-specific anatomy as shown in a series of 3D-printed petrous apex chondrosarcomas. Furthermore, the models created can be cut and drilled, revealing internal structures that allow for simulation of surgical procedures.

The protocol describes the fabrication of fully colored three-dimensional prints of patient-specific, anatomical skull models to be used for surgical simulation. The crucial steps of combining different imaging modalities, image segmentation, three-dimensional model extraction, and production of the prints are explained.

Three-dimensional (3D) printing technologies offer the possibility of visualizing patient-specific pathologies in a physical model of correct dimensions. ...

Novel Percutaneous Approach for Deployment of 3D Printed Coronary Stenosis Implants in Swine Models of Ischemic Heart Disease

Minimally invasive methods for creating models of focal coronary narrowing in large animals are challenging. Rapid prototyping using three-dimensionally (3D) printed coronary implants can be employed to percutaneously create a focal coronary stenosis. However, reliable delivery of the implants can be difficult without the use of ancillary equipment. We describe the use of a mother-and-child coronary guide catheter for stabilization of the implant and for effective delivery of the 3D printed implant to any desired location along the length of the coronary vessel. The focal coronary narrowing was confirmed under coronary cineangiography and the functional significance of the coronary stenosis was assessed using gadolinium-enhanced first-pass cardiac perfusion MRI. We showed that reliable delivery of 3D printed coronary implants in swine models (n = 11) of ischemic heart disease can be achieved through repurposing mother-and-child coronary guide catheters. Our technique simplifies the percutaneous delivery of coronary implants to create closed-chest swine models of focal coronary artery stenosis and can be performed expeditiously, with a low procedural failure rate.

We describe a novel, cost-effective, and efficient technique for percutaneous delivery of three-dimensionally printed coronary implants to create closed-chest swine models of ischemic heart disease. The implants were fixed in place using a mother-and-child extension catheter with high success rate.

Minimally invasive methods for creating models of focal coronary narrowing in large animals are challenging. Rapid prototyping using three-dimensionally ...

3D Planning and Printing of Patient Specific Implants for Reconstruction of Bony Defects

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical field using the constantly developing 3D planning and printing capabilities. Computer-assisted design (CAD) and computer assisted manufacturing (CAM) are used to describe the 3D planning and manufacturing of the product. The planning and manufacturing of 3D surgical guides and reconstruction implants is performed almost exclusively by engineers. As technology advances and software interfaces become more user-friendly, it raises a question regarding the possibility of transferring the planning and manufacturing to the clinician. The reasons for such a shift are clear: the surgeon has the idea of what he wants to design, and he also knows what is feasible and could be used in the operating room. It allows him to be prepared for any scenario/unexpected results during the operation and allows the surgeon to be creative and express his new ideas using the CAD software. The purpose of this method is to provide clinicians with the ability to create their own surgical guides and reconstruction implants. In this manuscript, a detailed protocol will provide a simple method for segmentation using segmentation software and implant planning using a 3D design software. Following the segmentation and stl file production using segmentation software, the clinician could create a simple patient specific reconstruction plate or a more complex plate with a cradle for bone graft positioning. Surgical guides can be created for accurate resection, hole preparation for proper reconstruction plate positioning or for bone graft harvesting and re-contouring. A case of lower jaw reconstruction following plate fracture and nonunion healing of a trauma sustained injury is detailed.

This protocol describes the use of 3D planning and printing for reconstruction of bony defects. We use segmentation tools to create 3D models followed by 3D design software to create patient specific implants for reconstruction purposes concomitant to ablative surgery or as a second stage.

We are in the midst of the 3D era in most aspects of life, and especially in medicine. The surgical discipline is one of the major players in the medical ...

Development and Evaluation of 3D-Printed Cardiovascular Phantoms for Interventional Planning and Training

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training physicians&#39; wire-skills as well as improving planning of interventional procedures. The aim of this study was to develop a manufacturing process of patient-specific 3D-printed models for cardiovascular interventions.
To create a 3D-printed elastic phantom, different 3D-printing materials were compared to porcine biological tissues (i.e., aortic tissue) in terms of mechanical characteristics. A fitting material was selected based on comparative tensile tests and specific material thicknesses were defined. Anonymized contrast-enhanced CT-datasets were collected retrospectively. Patient-specific volumetric models were extracted from these datasets and subsequently 3D-printed. A pulsatile flow loop was constructed to simulate the intraluminal blood flow during interventions. Models&#39; suitability for clinical imaging was assessed by x-ray imaging, CT, 4D-MRI and (Doppler) ultrasonography. Contrast medium was used to enhance visibility in x-ray-based imaging. Different catheterization techniques were applied to evaluate the 3D-printed phantoms in physicians&#39; training as well as for pre-interventional therapy planning.
Printed models showed a high printing resolution (~30 &#181;m) and mechanical properties of the chosen material were comparable to physiological biomechanics. Physical and digital models showed high anatomical accuracy when compared to the underlying radiological dataset. Printed models were suitable for ultrasonic imaging as well as standard x-rays. Doppler ultrasonography and 4D-MRI displayed flow patterns and landmark characteristics (i.e., turbulence, wall shear stress) matching native data. In a catheter-based laboratory setting, patient-specific phantoms were easy to catheterize. Therapy planning and training of interventional procedures on challenging anatomies (e.g., congenital heart disease (CHD)) was possible.
Flexible patient-specific cardiovascular phantoms were 3D-printed, and the application of common clinical imaging techniques was possible. This new process is ideal as a training tool for catheter-based (electrophysiological) interventions and can be used in patient-specific therapy planning.

Here we present development of a mock circulation setup for multimodal therapy evaluation, pre-interventional planning, and physician-training on cardiovascular anatomies. With the application of patient-specific tomographic scans, this setup is ideal for therapeutic approaches, training, and education in individualized medicine.

Catheter-based interventions are standard treatment options for cardiovascular pathologies. Therefore, patient-specific models could help training ...

Combining 3D-Printing and Electrospinning to Manufacture Biomimetic Heart Valve Leaflets

Electrospinning has become a widely used technique in cardiovascular tissue engineering as it offers the possibility to create (micro-)fibrous scaffolds with adjustable properties. The aim of this study was to create multilayered scaffolds mimicking the architectural fiber characteristics of human heart valve leaflets using conductive 3D-printed collectors.
Models of aortic valve cusps were created using commercial computer-aided design (CAD) software. Conductive polylactic acid was used to fabricate 3D-printed leaflet templates. These cusp negatives were integrated into a specifically designed, rotating electrospinning mandrel. Three layers of polyurethane were spun onto the collector, mimicking the fiber orientation of human heart valves. Surface and fiber structure was assessed with a scanning electron microscope (SEM). The application of fluorescent dye additionally permitted the microscopic visualization of the multilayered fiber structure. Tensile testing was performed to assess the biomechanical properties of the scaffolds.
3D-printing of essential parts for the electrospinning rig was possible in a short time for a low budget. The aortic valve cusps created following this protocol were three-layered, with a fiber diameter of 4.1 &#177; 1.6 &#181;m. SEM imaging revealed an even distribution of fibers. Fluorescence microscopy revealed individual layers with differently aligned fibers, with each layer precisely reaching the desired fiber configuration. The produced scaffolds showed high tensile strength, especially along the direction of alignment. The printing files for the different collectors are available as Supplemental File 1, Supplemental File 2, Supplemental File 3, Supplemental File 4, and Supplemental File 5.
With a highly specialized setup and workflow protocol, it is possible to mimic tissues with complex fiber structures over multiple layers. Spinning directly on 3D-printed collectors creates considerable flexibility in manufacturing 3D shapes at low production costs.

The presented method offers an innovative way for engineering biomimetic fiber structures in three-dimensional (3D) scaffolds (e.g., heart valve leaflets). 3D-printed, conductive geometries were used to determine shape and dimensions. Fiber orientation and characteristics were individually adjustable for each layer. Multiple samples could be manufactured in one setup.

Electrospinning has become a widely used technique in cardiovascular tissue engineering as it offers the possibility to create (micro-)fibrous scaffolds ...

3D Printing Model of a Patient's Specific Lumbar Vertebra

Selective dorsal rhizotomy (SDR) is a difficult, risky, and sophisticated operation, in which a laminectomy should not only expose an adequate surgical field of view but also protect the patient&#39;s spinal nerves from injury. Digital models play an important role in the pre-and intra-operation of SDR, because they can not only make doctors more familiar with the anatomical structure of the surgical site, but also provide precise surgical navigation coordinates for the manipulator. This study aims to create a 3D digital model of a patient-specific lumbar vertebra that can be used for planning, surgical navigation, and training of the SDR operation. The 3D printing model is also manufactured for more effective work during these processes.
Traditional orthopedic digital models rely almost entirely on computed tomography (CT) data, which is less sensitive to soft tissues. Fusion of the bone structure from CT and the neural structure from magnetic resonance imaging (MRI) is the key element for the model reconstruction in this study. The patient&#39;s specific 3D digital model is reconstructed for the real appearance of the surgical area and shows the accurate measurement of inter-structural distances and regional segmentation, which can effectively help in the preoperative planning and training of SDR. The transparent bone structure material of the 3D-printed model allows surgeons to clearly distinguish the relative relationship between the spinal nerve and the vertebral plate of the operated segment, enhancing their anatomical understanding and spatial sense of the structure. The advantages of the individualized 3D digital model and its accurate relationship between spinal nerve and bone structures make this method a good choice for preoperative planning of SDR surgery.

This study aims to create a 3D-printed model of a patient-specific lumbar vertebra, which contains both the vertebra and spinal nerve models fused from high-resolution computed tomography (HRCT) and MRI-Dixon data.

Selective dorsal rhizotomy (SDR) is a difficult, risky, and sophisticated operation, in which a laminectomy should not only expose an adequate surgical ...

3D Reconstruction for the Diagnosis and Treatment of Pulmonary Nodules

A 3D Digital Model for the Diagnosis and Treatment of Pulmonary Nodules

The three-dimensional (3D) reconstruction of pulmonary nodules using medical images has introduced new technical approaches for diagnosing and treating pulmonary nodules, and these approaches are progressively being acknowledged and adopted by physicians and patients. Nonetheless, constructing a relatively universal 3D digital model of pulmonary nodules for diagnosis and treatment is challenging due to device differences, shooting times, and nodule types. The objective of this study is to propose a new 3D digital model of pulmonary nodules that serves as a bridge between physicians and patients and is also a cutting-edge tool for pre-diagnosis and prognostic evaluation. Many AI-driven pulmonary nodule detection and recognition methods employ deep learning techniques to capture the radiological features of pulmonary nodules, and these methods can achieve a good area under-the-curve (AUC) performance. However, false positives and false negatives remain a challenge for radiologists and clinicians. The interpretation and expression of features from the perspective of pulmonary nodule classification and examination are still unsatisfactory. In this study, a method of continuous 3D reconstruction of the whole lung in horizontal and coronal positions is proposed by combining existing medical image processing technologies. Compared with other applicable methods, this method allows users to rapidly locate pulmonary nodules and identify their fundamental properties while also observing pulmonary nodules from multiple perspectives, thereby providing a more effective clinical tool for diagnosing and treating pulmonary nodules.

Author Spotlight: A 3D Digital Model for the Diagnosis and Treatment of Pulmonary Nodules  

The objective of this study is to develop a novel 3D digital model of pulmonary nodules that serves as a communication bridge between physicians and patients and is also a cutting-edge tool for pre-diagnosis and prognostic evaluation.

The three-dimensional (3D) reconstruction of pulmonary nodules using medical images has introduced new technical approaches for diagnosing and treating ...

Enhancing Radiotherapy with Web-Based Radiation Planning Assistant

Radiation Planning Assistant - A Web-based Tool to Support High-quality Radiotherapy in Clinics with Limited Resources

Access to radiotherapy worldwide is limited. The Radiation Planning Assistant (RPA) is a fully automated, web-based tool that is being developed to offer fully automated radiotherapy treatment planning tools to clinics with limited resources. The goal is to help clinical teams scale their efforts, thus reaching more patients with cancer. The user connects to the RPA via a webpage, completes a Service Request (prescription and information about the radiotherapy targets), and uploads the patient&#39;s CT image set. The RPA offers two approaches to automated planning. In one-step planning, the system uses the Service Request and CT scan to automatically generate the necessary contours and treatment plan. In two-step planning, the user reviews and edits the automatically generated contours before the RPA continues to generate a volume-modulated arc therapy plan. The final plan is downloaded from the RPA website and imported into the user&#39;s local treatment planning system, where the dose is recalculated for the locally commissioned linac; if necessary, the plan is edited prior to approval for clinical use.

Author Spotlight: Improving Radiation Therapy Access with Radiation Planning Assistant

This protocol describes a series of automated tools designed for high-quality radiotherapy autocontouring and autoplanning that are being packaged into a web-based service to maximize robustness and scalability while minimizing operational costs.

Access to radiotherapy worldwide is limited. The Radiation Planning Assistant (RPA) is a fully automated, web-based tool that is being developed to offer ...