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  1. A member recently messaged me with a question about a brain she printed from this file. I as posting the response here in the hope that it will help others in the community. QUESTION "I came across your 3D printable human brain model and was able to successfully print it. Thank you for sharing it! Now I need to post-process it and am wondering if you can explain how you post-processed your print? I have never done the post-processing before and am not sure the best approach to take. I have attached a picture of our printed brain for your reference. Thank you in advance for insight you can offer!" RESPONSE: Based on the picture you attached, it looks like you used a single extruder printer and printed both the supports and model in the same material, presumably PLA. You need to tear off the supports using pliers. This can be a time-consuming job as getting in every nook and cranny can be difficult. If you find the supports are stuck to much to the model, you may have to adjust some of the settings in your slicer software to compensate. There may be a rough surface where the supports touch the model that you can sand off. If you have a dual extrusion printer, you can print the supports using a water soluble material such as PVA, which makes the supports easy to remove by soaking in water. Dual extruders can be finicky and you will likely have to spend a lot of time trying out different settings to get the supports to work just right, including calibrating the XY offset of the second extruder, determining optimal print temperature for the PLA and support to work together, overhang speed, support infill percentage, etc. This process is very time consuming but gratifying once you get your printer dialed in. If you don't want to deal with the headache, embodi3D has a 3D printing service and can print and ship to you. Hope this helps. Dr. Mike
  2. Version

    148 downloads

    Transposition of the great arteries is a serious but rare heart defect present at birth, in which the two main arteries leaving the heart are reversed (transposed). Transposition of the great arteries is usually detected either prenatally or within the first hours to weeks of life. Transposition of the great arteries changes the way blood circulates through the body, leaving a shortage of oxygen in blood flowing from the heart to the rest of the body. Without an adequate supply of oxygen-rich blood, the body can't function properly and a child faces serious complications or death without treatment. Corrective surgery soon after birth is the usual treatment for transposition of the great arteries. There are three STL files available for download segmented as seen in the video and images. These files have been zipped to save space and data transfer. The model is provided for distribution on Embodi3D with the permission of the author, pediatric cardiologist Dr. Matthew Bramlet, MD, and is part of the Heart Library. We thank Dr. Bramlet and all others who are working to help children with congenital heart problems lead normal and happy lives. It is distributed by Dr. Bramlet under the Creative Commons license Attribution-NonCommercial-NoDerivs. Please respect the terms of the licensing agreement. A US quarter is shown for scale in the images below.

    Free

  3. Vascular Training Models Venous Models: IVC Filter Deployment/Retrieval Model: VIVC01000M Iliac Vein Stenosis Extension Model: VIVC01E2SC Gonadal Vein Embolization Extension Model: VGON01000C Femoral Vein Extension Model: VFEM01000C Flexible SVC Extension Model: VSVC01000F Vascular Training Models Arterial Models: Extendable Abdominal Aorta Model: AABD02000C Upper and Lower Leg Extension Model: AALE01000C Abdominal Aortic Aneurysm EVAR Model: AAAA01000C Stand-Alone Abdominal Aorta Model: AABD01000C Description: The gonadal vein embolization model is a two-part model that is compatible with the standard IVC filter deployment/ retrieval model. It consists of a modified IVC segment that snaps into place in the IVC position, and a distal gonadal vein segment. The pathologically dilated gonadal vein is from a real patient with severe pelvic congestion syndrome and consists of a dilated left gonadal vein that measures 11 mm in diameter. The abnormal vein can be accessed from the femoral or jugular approach and is perfect for deploying coils, occlusion devices, or foam. Once deployed the embolization devices can be easily removed.
    Procedures that this model can teach or practice: Gonadal vein embolization Renal vein sampling Adrenal vein sampling Compatibility: Iliac vein stenosis extension model (# VIVC01E2SC) Femoral vein extension model (# VFEM01000C) Flexible SVC extension model (# VSVC01000F) Required models: This model should be used with the IVC Filter Deployment and Retrieval Model (# VIVC01000M) For questions and pricing contact us. Please include the model name and number with your inquiry: Gonadal Vein Embolization Extension Model (# VGON01000C)
  4. Vascular Training Models Venous Models: IVC Filter Deployment/Retrieval Model: VIVC01000M Iliac Vein Stenosis Extension Model: VIVC01E2SC Gonadal Vein Embolization Extension Model: VGON01000C Femoral Vein Extension Model: VFEM01000C Flexible SVC Extension Model: VSVC01000F Vascular Training Models Arterial Models: Extendable Abdominal Aorta Model: AABD02000C Upper and Lower Leg Extension Model: AALE01000C Abdominal Aortic Aneurysm EVAR Model: AAAA01000C Stand-Alone Abdominal Aorta Model: AABD01000C Description: The iliac vein stenosis model is a single piece that replaces Part E (common iliac veins) in the IVC filter model. This model contains a high grade stenosis in the proximal left common iliac vein, the classic position of the so-called May-Thurner stenosis. In May-Thurner syndrome, chronic compression and scarring of the proximal left common iliac vein, is caused by the crossing right common iliac artery. This results in stenosis of the left common iliac vein, slow blood flow, and eventually clotting and formation of deep vein thrombosis (DVT). After the DVT is cleared with anticoagulation or thrombectomy/thrombolysis, the iliac vein stenosis must be treated with venous stenting. This model has a 4 mm thick, 9 mm wide stenosis at the crossing point between the left common iliac vein and the right common iliac artery. It is perfect for practicing venous stenting and thrombectomy/ thrombolysis.
    Procedures that this model can teach or practice: venous stenting venous thrombectomy venous thrombolysis venous catheterization Compatibility: Gonadal vein embolization extension model (# VGON01000C) Femoral vein extension model (# VFEM01000C) Flexible SVC extension model (# VSVC01000F) Required models: This model should be used with the IVC filter deployment/ retrieval model (# VIVC01000M) For questions and pricing contact us. Please include the model name and number with your inquiry: Iliac Vein Stenosis Extension model (# VIVC01E2SC)
  5. Vascular Training Models Venous Models: IVC Filter Deployment/Retrieval Model: VIVC01000M Iliac Vein Stenosis Extension Model: VIVC01E2SC Gonadal Vein Embolization Extension Model: VGON01000C Femoral Vein Extension Model: VFEM01000C Flexible SVC Extension Model: VSVC01000F Vascular Training Models Arterial Models: Extendable Abdominal Aorta Model: AABD02000C Upper and Lower Leg Extension Model: AALE01000C Abdominal Aortic Aneurysm EVAR Model: AAAA01000C Stand-Alone Abdominal Aorta Model: AABD01000C Description: The IVC filter deployment/retrieval medical training model includes all the major venous structures in the human torso from the right jugular vein of the neck to the right and left common femoral veins at the level of the hips. The model allows for the education and training in a variety of venous and IVC filter related procedures. The model was created from a real CT scan so the vessel positions, diameters, and angles are all real. Entry points are present at the right jugular vein and brachiocephalic vein for upper body access, and the bilateral common femoral veins for lower body access. Attachments are present to make placement of a real vascular sheath easy. The model can be used to illustrate specific devices for the procedures listed and is used by medical device companies to demonstrate and teach the use of their products. The IVC model comes in a rugged and portable carrying case and is easily transportable. It assembles and disassembles in less than 20 seconds. A variety of extensions are available to expand the number of procedures that can be simulated.
    Procedures that this model can teach or practice: IVC filter placement, jugular or femoral approach Common iliac filter placement, jugular or femoral approach IVC filter retrieval Venous stenting IVC and iliac vein thrombectomy or thrombolysis Venous embolization Hepatic vein cannulation Compatibility: Iliac vein stenosis extension model (# VIVC01E2SC) Gonadal vein embolization extension model (# VGON01000C) Femoral vein extension model (# VFEM01000C) Flexible SVC extension model (# VSVC01000F) For questions and pricing contact us. Please include the model name and number with your inquiry: IVC Filter Deployment and Retrieval model (# VIVC01000M)
  6. From the album: embodi3D 3D Printed Models

    This skull with left MCA aneurysm was printed by embodi3D for a customer who wants to use the model for simulating neurosurgical aneurysm clipping.
  7. Version

    139 downloads

    This anatomically accurate 3D printable sphenoid bone was created by Dr. Marco Vettorello, who has graciously given permission to share it here. The sphenoid bone forms the base of the skull. It houses the sella turcica, which protects the pituitary gland and the sphenoid air cells which are part of the paranasal sinus system. The file is in STL format and compressed with ZIP. This file is also available here.

    Free

  8. We recently 3D printed a multimaterial skull with MCA aneurysm from a CTA head for customer who needed the skull in rigid plastic and the vessels and aneurysm in flexible material. The model will be used by neurosurgeons to practice intracranial aneurysm clipping surgery. To properly simulate the surgery, the skull needs to be hard and the vessels elastic. Combining two materials (and two printers!) provides the best solution. The model was created on democratiz3D. You can learn more about embodi3D's printing service here.
  9. I receive a lot of inquiries to my account. I'm going to try to share them with the community in the hope that any information that is shared can help many others. A member recently contacted me and asked the following: "I am a Biomaterials and Tissue Engineer by profession and recently got into 3d printing of medical implants. I would be greatly obliged if you could please advice me on designing 'cranial mesh' My task is to design titanium based cranial mesh. I would like to know if you can suggest me any tutorial on the same." Another member asks, " I am a resident in neurosurgery in Brazil and I have a dream to allow cheap cranioplasty for those in need that depend on Brazilian public health system. If you have some sort of tutorial using free software to make those prosthetic cranial grafts of a cheap way to make a mold out of it I will be glad to hear from you. I am planning on buying the ultimaker 2 printer which allows direct PEEK print and also PLA print for mold to go through autoclave." I must admit that I have limited experience with craniofacial implants. I know that the physicians at Walter Reed Army Medical Center in Bethesda Maryland are doing pioneering work in the field. Regarding making titanium-based implants I am unaware of any tutorials, but a search on Pubmed has yielded a few helpful articles. Here is one https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4073471/ From what I have seen most of these implants are designed using the Mimics system by Materialise. Regarding the low-cost solution for cranial implants, I'm not familiar with any freeware software that specifically does implants. From the hardware perspective, you may want to consider a Form 2 stereolithographic printer in addition to the Ultimaker 2 (FYI, there is a new Ultimaker 3 printer out). Formlabs, the makers of the Form 2 have a tutorial on using their printer to make molds for casting. https://formlabs.com/blog/3d-printing-for-injection-molding/ Formlabs has a dental biocompatible resin that I know some hospitals (Mayo Clinic) are using for in-surgery cutting guides. I heard them talk about that at a conference I recently attended. Whatever you do, make sure you follow the health safety rules in your country and take all necessary steps for patient safety.
  10. Version

    1,004 downloads

    -> IMPROVED VERSION OF THIS FILE IS AVAILABLE HERE <-- This 3D printable model of a human heart was generated from a contrast enhanced CT scan. The model comes in 4 slices, and demonstrates the detailed anatomy of the human heart in exquisite detail. Each slice stacks on top of the prior slice to form a complete human heart. Individual slices show the detailed cardiac anatomy of the right and left ventricles, and right and left atria, and outflow tracts. Perfect for educational purposes. Download this model for free and 3D print the model yourself! If you find this and other free medical models available for download on Embodi3d.com useful, please give back to the community by uploading and sharing a medical model of your design.

    $4.99

  11. Version

    205 downloads

    Normally there are two main blood vessels leaving the heart: the aorta, carrying blood to the body, and the pulmonary artery that branches immediately to carry blood to each lung. Instead of having a separate pulmonary artery and aorta, each with its own three-leafed valves, a baby with truncus arteriosus has only one great blood vessel or trunk leaving the heart, which then branches into blood vessels that go to the lungs and the body. This great vessel usually has one large valve which may have between two and five leaflets. Usually this great vessel sits over both the left and right ventricle. The upper portion of the wall between these two chambers is missing, resulting in what is known as a ventricular septal defect (VSD). There are 3 separate files as well as a fourth STL file for 3D printing the whole model. The three part model has holes for magnets, which can be used to connect and separate the pieces. All the STL files have been zipped to conserve space. The model is provided for distribution on Embodi3D with the permission of the author, pediatric cardiologist Dr. Matthew Bramlet, MD, and is part of the Congenital Heart Defects library. We thank Dr. Bramlet and all others who are working to help children with congenital heart problems lead normal and happy lives. It is distributed by Dr. Bramlet under the Creative Commons license Attribution-NonCommercial-NoDerivs. Please respect the terms of the licensing agreement. A US quarter is shown for scale in the images below.

    Free

  12. Version 1.0.0

    311 downloads

    There are four STL files for 3D printing demonstrating a moderate secundum atrial septal defect (ASD) and a mild coarctation. An atrial septal defect is a birth defect of the heart in which there is a hole in the wall (septum) that divides the upper chambers of the heart (atria). A hole can vary in size and may close on its own or may require surgery. If one of these openings does not close, a hole is left, and it is called an atrial septal defect. The hole increases the amount of blood that flows through the lungs and over time, it may cause damage to the blood vessels in the lungs. Damage to the blood vessels in the lungs may cause problems in adulthood, such as high blood pressure in the lungs and heart failure. Other problems may include abnormal heartbeat, and increased risk of stroke. MRI obtained for evaluation of distal arch and pulmonary veins due to findings of pulmonary overcirculation out of proportion to typical ASD pathophysiology. The MRI provided a complete anatomic overview and quantified the right sided enlargement from the 2:1 shunt through the ASD. Due to saturation band nulling of blood returning through the right sided pulmonary veins, there was excellent definition of the ASD due to the "dark" blood mixing with the "bright" blood and outlining the borders of the ASD which transfers to the model very well. Please keep in mind, that the model represents a heart in end-systole rather than diastole. Disclaimer: The available model has been validated to demonstrate the case’s pathologic features on a Z450 3D printer, (3DSystems, Circle Rock Hill, South Carolina)(or other printer as appropriate). While the mask applied to the original DICOM images accurately represents the anatomic features, some anatomic detail may be lost due to thin walled structures or inadequate supporting architecture; while other anatomic detail may be added due to similar limitations resulting in bleeding of modeling materials into small negative spaces. However, intracardiac structures, relationships, and pathologic features represent anatomic findings to scale and in high detail. Credit: The model is provided for distribution on Embodi3D with the permission of the author, pediatric cardiologist Dr. Matthew Bramlet, MD, and is part of the Congenital Heart Defects library. We thank Dr. Bramlet and all others who are working to help children with congenital heart problems lead normal and happy lives. It is distributed by Dr. Bramlet under the Creative Commons license Attribution-NonCommercial-NoDerivs. Please respect the terms of the licensing agreement.

    Free

  13. valchanov

    Project Fancy Skull

    I decided to give my Prusa MK3 printer a real challenge, so I cut my best skull model, I added some slots for neodymium magnets and I started to print the parts. I'm done with the half of them and I'll update my post when I'm done.
  14. Dr. Mike

    Lumbar Vertebra

    Version 2.0

    482 downloads

    Anatomically accurate full-size human lumbar vertebra created from a real CT scan. File in Collada format. See the video here: Copyright 2013 Embodi3d

    Free

  15. Currently, Ebola is the most dreaded epidemic in the world which accounts to more than 5,000 lives lost mainly in Africa. As of this writing, the Ebola disease does not have any vaccines available. Those who are inflicted with this virus are treated based on their symptoms. To make matters worse, the scientists all over the world is running a race against a global Ebola pandemic threat that is about to become a reality. However, the spread of the Ebola virus has also given the opportunity for DIY enthusiasts to find a cure for the virus using DIY biotech experimentation. In fact, fighting Ebola using digital fabrication maybe one of the solutions to the alarming problem. So how will DIY biotech come into the fore when it comes to treating Ebola virus? One of the experimental treatments show that transfusion of blood from survivors is the best medical practice that can cure victims afflicted with this disease. Since there is a 24-day incubation, the DIY bio movement can help a lot by creating digitally fabricated centrifuges to help with plasma separation. Toolkits should be built around the centrifuge using digital open source software so that it will be easier for people to sterilize, draw blood and do blood typing. These kits should be able to run on locally available energy sources like solar power and car or motorcycle batteries. With the use of available local energy sources, this technology will be accessible to areas hard hit by Ebola. The more these DIY-fabricated component are available to third world countries in Africa, the more lives will be saved, the higher the chances of containing the virus and prevention of a global Ebola pandemic.
  16. Version 1.0.0

    180 downloads

    This is an anonymized CT scan DICOM dataset to be used for teaching on how to create a 3D printable models.

    Free

  17. Mezoforta

    3D Printing My Skull

    I'm trying to 3d print my own skull just for fun and well I have the DCOM file but every time when I try and convert it the whole skull doesn't come out. Whenever I convert the DCOM file any of them it only gives me from the top do about the middle of the eye socket and i want the whole thing. Can someone please help me and tell me what i might be doing wrong.
  18. Hello the Biomedical 3D Printing community, it's Devarsh Vyas here writing after a really long time! This time i'd like to share my personal experience and challenges faced with respect to medical 3D Printing from the MRI data. This can be a knowledge sharing and a debatable topic and I am looking forward to hear and know what other experts here think of this as well with utmost respect. In the Just recently concluded RSNA conference at Chicago had a wave of technology advancements like AI and 3D Printing in radiology. Apart from that the shift of radiologists using more and more MR studies for investigations and the advancements with the MRI technology have forced radiologists and radiology centers (Private or Hospitals) to rely heavily on MRI studies. We are seeing medical 3D Printing becoming mainstream and gaining traction and excitement in the entire medical fraternity, for designers who use the dicom to 3D softwares, whether opensource or FDA approved software know that designing from CT is fairly automated because of the segmentation based on the CT hounsifield units however seldom we see the community discuss designing from MRI, Automation of segmentation from MRI data, Protocols for MRI scan for 3D Printing, Segmentation of soft tissues or organs from MRI data or working on an MRI scan for accurate 3D modeling. Currently designing from MRI is feasible, but implementation is challenging and time consuming. We should also note reading a MRI scan is a lot different than reading a CT scan, MRI requires high level of anatomical knowledge and expertise to be able to read, differentiate and understand the ROI to be 3D Printed. MRI shows a lot more detailed data which maybe unwanted in the model that we design. Although few MRI studies like the contrast MRI of the brain, Heart and MRI angiograms can be automatically segmented but scans like MRI of the spine or MRI of the liver, Kidney or MRI of knee for example would involve a lot of efforts, expertise and manual work to be done in order to reconstruct and 3D Print it just like how the surgeon would want it. Another challenge MRI 3D printing faces is the scan protocols, In CT the demand of high quality thin slices are met quite easily but in MRI if we go for protocols for T1 & T2 weighted isotropic data with equal matrix size and less than 1mm cuts, it would increase the scan time drastically which the patient has to bear in the gantry and the efficiency of the radiology department or center is affected. There is a lot of excitement to create 3D printed anatomical models from the ultrasound data as well and a lot of research is already being carried out in that direction, What i strongly believe is the community also need advancements in terms of MRI segmentation for 3D printing. MRI, in particular, holds great potential for 3D printing, given its excellent tissue characterization and lack of ionizing radiation but model accuracy, manual efforts in segmentation, scan protocols and expertise in reading and understanding the data for engineers have come up as a challenge the biomedical 3D printing community needs to address. These are all my personal views and experiences I've had with 3D Printing from MRI data. I'm open to and welcome any tips, discussions and knowledge sharing from all the other members, experts or enthusiasts who read this. Thank you very much!
  19. If you are planning on using the democratiz3D service to automatically convert a medical scan to a 3D printable STL model, or you just happen to be working with medical scans for another reason, it is important to know if you are working with a CT (Computed Tomography or CAT) or MRI (Magnetic Resonance Imaging) scan. In this tutorial I'll show you how to quickly and easily tell the difference between a CT and MRI. I am a board-certified radiologist, and spent years mastering the subtleties of radiology physics for my board examinations and clinical practice. My goal here is not to bore you with unnecessary detail, although I am capable of that, but rather to give you a quick, easy, and practical way to understand the difference between CT and MRI if you are a non-medical person. Interested in Medical 3D Printing? Here are some resources: Free downloads of hundreds of 3D printable medical models. Automatically generate your own 3D printable medical models from CT scans. Have a question? Post a question or comment in the medical imaging forum. A Brief Overview of How CT and MRI Works For both CT (left) and MRI (right) scans you will lie on a moving table and be put into a circular machine that looks like a big doughnut. The table will move your body into the doughnut hole. The scan will then be performed. You may or may not get IV contrast through an IV. The machines look very similar but the scan pictures are totally different! CT and CAT Scans are the Same A CT scan, from Computed Tomography, and a CAT scan from Computed Axial Tomography are the same thing. CT scans are based on x-rays. A CT scanner is basically a rotating x-ray machine that takes sequential x-ray pictures of your body as it spins around. A computer then takes the data from the individual images, combines that with the known angle and position of the image at the time of exposure, and re-creates a three-dimensional representation of the body. Because CT scans are based on x-rays, bones are white and air is black on a CT scan just as it is on an x-ray as shown in Figure 1 below. Modern CT scanners are very fast, and usually the scan is performed in less than five minutes. Figure 1: A standard chest x-ray. Note that bones are white and air is black. Miscle and fat are shades of gray. CT scans are based on x-ray so body structures have the same color as they don on an x-ray. How does MRI Work? MRI uses a totally different mechanism to generate an image. MRI images are made using hydrogen atoms in your body and magnets. Yes, super strong magnets. Hydrogen is present in water, fat, protein, and most of the "soft tissue" structures of the body. The doughnut of an MRI does not house a rotating x-ray machine as it does in a CT scanner. Rather, it houses a superconducting electromagnet, basically a super strong magnet. The hydrogen atoms in your body line up with the magnetic field. Don't worry, this is perfectly safe and you won't feel anything. A radio transmitter, yes just like an FM radio station transmitter, will send some radio waves into your body, which will knock some of the hydrogen atoms out of alignment. As the hydrogen nuclei return back to their baseline position they emit a signal that can be measured and used to generate an image. MRI Pulse Sequences Differ Among Manufacturers The frequency, intensity, and timing of the radio waves used to excite the hydrogen atoms, called a "pulse sequence," can be modified so that only certain hydrogen atoms are excited and emit a signal. For example, when using a Short Tau Inversion Recovery (STIR) pulse sequence hydrogen atoms attached to fat molecules are turned off. When using a Fluid Attenuation Inversion Recovery (FLAIR) pulse sequence, hydrogen atoms attached to water molecules are turned off. Because there are so many variables that can be tweaked there are literally hundreds if not thousands of ways that pulse sequences can be constructed, each generating a slightly different type of image. To further complicate the matter, medical scanner manufacturers develop their own custom flavors of pulse sequences and give them specific brand names. So a balanced gradient echo pulse sequence is called True FISP on a Siemens scanner, FIESTA on a GE scanner, Balanced FFE on Philips, BASG on Hitachi, and True SSFP on Toshiba machines. Here is a list of pulse sequence names from various MRI manufacturers. This Radiographics article gives more detail about MRI physics if you want to get into the nitty-gritty. Figure 2: Examples of MRI images from the same patient. From left to right, T1, T2, FLAIR, and T1 post-contrast images of the brain in a patient with a right frontal lobe brain tumor. Note that tissue types (fat, water, blood vessels) can appear differently depending on the pulse sequence and presence of IV contrast. How to Tell the Difference Between a CT Scan and an MRI Scan? A Step by Step Guide Step 1: Read the Radiologist's Report The easiest way to tell what kind of a scan you had is to read the radiologist's report. All reports began with a formal title that will say what kind of scan you had, what body part was imaged, and whether IV contrast was used, for example "MRI brain with and without IV contrast," or "CT abdomen and pelvis without contrast." Step 2: Remember Your Experience in the MRI or CT (CAT) Scanner Were you on the scanner table for less than 10 minutes? If so you probably had a CT scan as MRIs take much longer. Did you have to wear earmuffs to protect your hearing from loud banging during the scan? If so, that was an MRI as the shifting magnetic fields cause the internal components of the machine to make noise. Did you have to drink lots of nasty flavored liquid a few hours before the scan? If so, this is oral contrast and is almost always for a CT. How to tell the difference between CT and MRI by looking at the pictures If you don't have access to the radiology report and don't remember the experience in the scanner because the scan was A) not done on you, or you were to drunk/high/sedated to remember, then you may have to figure out what kind of scan you had by looking at the pictures. This can be complicated, but don't fear I'll show you how to figure it out in this section. First, you need to get a copy of your scan. You can usually get this from the radiology or imaging department at the hospital or clinic where you had the scan performed. Typically these come on a CD or DVD. The disc may already have a program that will allow you to view the scan. If it doesn't, you'll have to download a program capable of reading DICOM files, such as 3D Slicer. Open your scan according to the instructions of your specific program. You may notice that your scan is composed of several sets of images, called series. Each series contains a stack of images. For CT scans these are usually images in different planes (axial, coronal, and sagittal) or before and after administration of IV contrast. For MRI each series is usually a different pulse sequence, which may also be before or after IV contrast. Step 3: Does the medical imaging software program tell you what kind of scan you have? Most imaging software programs will tell you what kind of scan you have under a field called "modality." The picture below shows a screen capture from 3D Slicer. Looking at the Modality column makes it pretty obvious that this is a CT scan. Figure 3: A screen capture from the 3D Slicer program shows the kind of scan under the modality column. Step 4: Can you see the CAT scan or MRI table the patient is laying on? If you can see the table that the patient is laying on or a brace that their head or other body part is secured in, you probably have a CT scan. MRI tables and braces are designed of materials that don't give off a signal in the MRI machine, so they are invisible. CT scan tables absorb some of the x-ray photons used to make the picture, so they are visible on the scan. Figure 4: A CT scan (left) and MRI (right) that show the patient table visible on the CT but not the MRI. Step 5: Is fat or water white? MRI usually shows fat and water as white. In MRI scans the fat underneath the skin or reservoirs of water in the body can be either white or dark in appearance, depending on the pulse sequence. For CT however, fat and water are almost never white. Look for fat just underneath the skin in almost any part of the body. Structures that contained mostly water include the cerebrospinal fluid around the spinal cord in the spinal canal and around the brain, the vitreous humor inside the eyeballs, bile within the gallbladder and biliary tree of the liver, urine within the bladder and collecting systems of the kidneys, and in some abnormal states such as pleural fluid in the thorax and ascites in the abdomen. It should be noted that water-containing structures can be made to look white on CT scans by intentional mixing of contrast in the structures in highly specialized scans, such as in a CT urogram or CT myelogram. But in general if either fat or fluid in the body looks white, you are dealing with an MRI. Step 6: Is the bone black? CT never shows bones as black. If you can see bony structures on your scan and they are black or dark gray in coloration, you are dealing with an MRI. On CT scans the bone is always white because the calcium blocks (attenuates) the x-ray photons. The calcium does not emit a signal in MRI scans, and thus appears dark. Bone marrow can be made to also appear dark on certain MRI pulse sequences, such as STIR sequences. If your scan shows dark bones and bone marrow, you are dealing with an MRI. A question I am often asked is "If bones are white on CT scans, if I see white bones can I assume it is a CT?" Unfortunately not. The calcium in bones does not emit signal on MRI and thus appears black. However, many bones also contain bone marrow which has a great deal of fat. Certain MRI sequences like T1 and T2 depict fat as bright white, and thus bone marrow-containing bone will look white on the scans. An expert can look carefully at the bone and discriminate between the calcium containing cortical bone and fat containing medullary bone, but this is beyond what a layperson will notice without specialized training. Self Test: Examples of CT and MRI Scans Here are some examples for you to test your newfound knowledge. Example 1 Figure 5A: A mystery scan of the brain Look at the scan above. Can you see the table that the patient is laying on? No, so this is probably an MRI. Let's not be hasty in our judgment and find further evidence to confirm our suspicion. Is the cerebrospinal fluid surrounding the brain and in the ventricles of the brain white? No, on this scan the CSF appears black. Both CT scans and MRIs can have dark appearing CSF, so this doesn't help us. Is the skin and thin layer of subcutaneous fat on the scalp white? Yes it is. That means this is an MRI. Well, if this is an MRI than the bones of the skull, the calvarium, should be dark, right? Yes, and indeed the calvarium is as shown in Figure 5B. You can see the black egg shaped oval around the brain, which is the calcium containing skull. The only portion of the skull that is white is in the frontal area where fat containing bone marrow is present between two thin layers of calcium containing bony cortex. This is an MRI. Figure 5B: The mystery scan is a T1 spoiled gradient echo MRI image of the brain. Incidentally this person has a brain tumor involving the left frontal lobe. Example 2 Figure 6A: Another mystery scan of the brain Look at the scan above. Let's go through our process to determine if this is a CT or MRI. First of all, can you see the table the patient is lying on or brace? Yes you can, there is a U-shaped brace keeping the head in position for the scan. We can conclude that this is a CT scan. Let's investigate further to confirm our conclusion. Is fat or water white? If either is white, then this is an MRI. In this scan we can see both fat underneath the skin of the cheeks which appears dark gray to black. Additionally, the material in the eyeball is a dark gray, immediately behind the relatively white appearing lenses of the eye. Finally, the cerebrospinal fluid surrounding the brainstem appears gray. This is not clearly an MRI, which further confirms our suspicion that it is a CT. If indeed this is a CT, then the bones of the skull should be white, and indeed they are. You can see the bright white shaped skull surrounding the brain. You can even see part of the cheekbones, the zygomatic arch, extending forward just outside the eyes. This is a CT scan. Figure 6B: The mystery scan is a CT brain without IV contrast. Example 3 Figure 7A: A mystery scan of the abdomen In this example we see an image through the upper abdomen depicting multiple intra-abdominal organs. Let's use our methodology to try and figure out what kind of scan this is. First of all, can you see the table that the patient is laying on? Yes you can. That means we are dealing with the CT. Let's go ahead and look for some additional evidence to confirm our suspicion. Do the bones appear white? Yes they do. You can see the white colored thoracic vertebrae in the center of the image, and multiple ribs are present, also white. If this is indeed a CT scan than any water-containing structures should not be white, and indeed they are not. In this image there are three water-containing structures. The spinal canal contains cerebrospinal fluid (CSF). The pickle shaped gallbladder can be seen just underneath the liver. Also, this patient has a large (and benign) left kidney cyst. All of these structures appear a dark gray. Also, the fat underneath the skin is a dark gray color. This is not in MRI. It is a CT. Figure 7B: The mystery scan is a CT of the abdomen with IV contrast Example 4 Figure 8A: A mystery scan of the left thigh Identifying this scan is challenging. Let's first look for the presence of the table. We don't see one but the image may have been trimmed to exclude it, or the image area may just not be big enough to see the table. We can't be sure a table is in present but just outside the image. Is the fat under the skin or any fluid-filled structures white? If so, this would indicate it is an MRI. The large white colored structure in the middle of the picture is a tumor. The fat underneath the skin is not white, it is dark gray in color. Also, the picture is through the mid thigh and there are no normal water containing structures in this area, so we can't use this to help us. Well, if this is a CT scan than the bone should be white. Is it? The answer is no. We can see a dark donut-shaped structure just to the right of the large white tumor. This is the femur bone, the major bone of the thigh and it is black. This cannot be a CT. It must be an MRI. This example is tricky because a fat suppression pulse sequence was used to turn the normally white colored fat a dark gray. Additionally no normal water containing structures are present on this image. The large tumor in the mid thigh is lighting up like a lightbulb and can be confusing and distracting. But, the presence of black colored bone is a dead giveaway. Figure 8B: The mystery scan is a contrast-enhanced T2 fat-suppressed MRI Conclusion: Now You Can Determine is a Scan is CT or MRI This tutorial outlines a simple process that anybody can use to identify whether a scan is a CT or MRI. The democratiz3D service on this website can be used to convert any CT scan into a 3D printable bone model. Soon, a feature will be added that will allow you to convert a brain MRI into a 3D printable model. Additional features will be forthcoming. The service is free and easy to use, but you do need to tell it what kind of scan your uploading. Hopefully this tutorial will help you identify your scan. If you'd like to learn more about the democratiz3D service click here. Thank you very much and I hope you found this tutorial to be helpful. Nothing in this article should be considered medical advice. If you have a medical question, ask your doctor.
  20. I receive a lot of inquiries to my account. I'm going to try to share them with the community in the hope that any information that is shared can help many others. A member recently contacted me and asked the following: "Do you have any experience in dicom images by TUI mode in Voluson E10, for print 3d fetus models" Unfortunately, I don't personally have experience with 3D printing ultrasound images. I'm not sure how the slice-by-slice registration will work as ultrasound images are not in fixed orthographic planes. However, I know it must be possible since there is a company that is 3D printing fetuses. http://www.3ders.org/articles/20160118-3d-printed-fetuses-the-hottest-parenting-trend-of-2016.html Anyone in the community have experience with converting ultrasound to STL?
  21. Version 1.0.0

    48 downloads

    This 3D printable STL file contains a model of the torso, neck, and arms was derived from a real medical CT scan and shows anatomic structures in great detail. This model was created using the democratiz3D free online 3D model creation service. QIN-HN-01-0003

    Free

  22. Version 1.0.0

    18 downloads

    This 3D printable STL file contains a model of the right shoulder was derived from a real medical CT scan. It shows the pectoralis, deltoid, biceps, and triceps muscles, as well as musculature of the chest wall. This model was created using the democratiz3D free online 3D model creation service. QIN-HN-01-0003

    Free

  23. Version 1.0.0

    8 downloads

    This 3D printable STL file contains a model of the muscles of the chest and back was derived from a real medical CT scan. The pectoralis, latissimus dorso, scalene and other muscles are shown in great detail. This model was created using the democratiz3D free online 3D model creation service. QIN-HN-01-0003

    Free

  24. Version 1.0.0

    9 downloads

    This 3D printable STL file contains a model of the left shoulder was derived from a real medical CT scan. It shows the deltoid, pectoralis, triceps, and biceps muscles in great detail. Also, the muscles of the chest wall and ribs are also shown. This model was created using the democratiz3D free online 3D model creation service. QIN-HN-01-0003

    Free

  25. Version 1.0.0

    31 downloads

    This 3D printable STL file contains a model of the torso, including the spine, shoulders and arms, pelvis, and proximal legs. It was derived from a real medical CT scan. This model was created using the democratiz3D free online 3D model creation service. QIN-HN-01-0003

    Free

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