Tag Archives: CT-scan

CT scans reveal the secrets of a 200-million-year-old dinosaur — and you can 3D print it for free

CT scans of a Jurassic dinosaur have offered paleontologists a spectacular view. The same technology also allows anyone with a 3D printer to recreate the skull, for free.

The profile view of the Massospondylus skull. Image credits: Kimberley Chapelle.

If you think about it, using CT scans for paleontology makes a lot of sense; if it’s accurate enough for human medicine, it should also work fine for ancient fossils — and it does. Paleontologists have increasingly used the technology in their research, with impressive results. So when Kimi Chapelle started analyzing Massospondylus skull, she knew this was the way to go. She managed to digitally rebuild every bone of Massospondylus‘s cranium, even revealing details such as nerves exiting the brain and the balance organs of the inner ear.

“I was amazed when I started digitally reconstructing Massospondylus‘ skull, and found all these features that had never been described,” said Chapelle, “it just goes to show that researchers still have a lot to learn about South Africa’s dinosaurs.”

Named after the celebrated anatomist Sir Richard Owen, Massospondylus is one of South Africa’s most well-represented dinosaurs. Hundreds of fossils have been discovered across the country, but even so, the dinosaur still holds some of its secrets. This is where Chapelle, a PhD student at the Evolutionary Studies Institute at the University of the Witwatersrand in Johannesburg, South Africa (Wits), enters the stage.

Using a CT machine to peer inside the dinosaur’s head, she managed to obtain an unprecedented view of the skull, revealing minute yet important features.

For instance, she revealed how the inner ear and the middle ear were connected and found that the bones that surround the brain in this specific fossil were not fully fused.

But perhaps even more excitingly, along with her published paper — which is free for anyone to read — she also released a 3D surface file of the skull. This file is available for anyone to download, which means that you, me, or anyone with a 3D printer can build his own dinosaur skull, identic with the original to the last detail.

 

The profile view of the Massospondylus skull after being scanned. Image credits: Kimberley Chapelle.

“This means any researcher or member of the public can print their own Massospondylus skull at home,” Chapelle said in a statement. “I was amazed when I started digitally reconstructing Massospondylus’ skull, and found all these features that had never been described. It just goes to show that researchers still have a lot to learn about South Africa’s dinosaurs.”

Massospondylus was a mid-size sauropodomorph, around 4 meters (13 ft) in length,  weighing approximately 1,000 kilograms (2200 lb). Researchers have long debated its diet and lifestyle, though recent studies strongly suggest that it was herbivorous or omnivorous, not carnivorous. Interestingly, scientists have also found fossils where these dinosaurs had rocks inside their stomachs. This was interpreted as a gastric mill, to aid ingestion of plant material, compensating for its inability to chew — as is common with several modern birds.

Relative scale of Massospondylus. Image credits: Matt Martyniuk / Dinoguy2.

This new type of study opens up new avenues for research. As more and more dinosaur fossils are analyzed this way, new comparisons can be made, and we can learn more about how they acted in their natural environment.

“By comparing the inner ear to that of other dinosaurs, we can try and interpret things like how they held their heads and how they moved. You can actually see tiny replacement teeth in the bones of the jaws, showing us that Massospondylus continuously replaced its teeth, like crocodiles do, but unlike humans that can only do it once,” says Chapelle.

Chappelle hopes that ultimately she will be able to answer some of the hardest questions about this intriguing species, including how such a ton-weighing giant grew from babies weighing less than 100g.

Journal Reference: Kimberley E.J. Chapelle , Jonah N. Choiniere. A revised cranial description of Massospondylus carinatus Owen (Dinosauria: Sauropodomorpha) based on computed tomographic scans and a review of cranial characters for basal Sauropodomorpha. https://doi.org/10.7717/peerj.4224

Undergoing a lung CT scan can help people quit smoking — regardless of results

British researchers have shown that something as simple as undergoing a lung CT scan might help people quit smoking. Even if it comes out fine.

Image credist: Geralt / Pixabay.

A smoking gun

The World Health Organization estimates that there are 1.1 billion smokers in the world — that’s every one in three adults. China is by far the biggest producer and consumer of cigarettes, with more than 350 million residents being smokers. India follows with 120 million smokers, while the US can ‘boast’ 36.5 million smokers. Tobacco ends up killing half of its users.

In recent times, smoking rates have gone down dramatically in the developed world. Countries like England and Australia are reporting all-time lows in smoking rates, partially fueled by higher taxes. In the European Union, banning smoking inside bars and clubs also played a vital role, but still — a worrying number of people still smoke, ignoring the numerous and far reaching health hazards.

The reasons why people start smoking aren’t really that varied. Most people start smoking in their teens, due to peer or cultural pressure (the smoking is cool idea). Almost 90% of smokers picked up the habit by 18, and 99% of smokers picked it up by the time they were 26. Usually, when smokers reach adulthood, they’re already addicted and find it very hard to quit. If you talk to most smokers, they’ll tell you they’ve tried quitting at least once but failed for one reason or another. There are countless books and ‘methods’ to quit smoking, but there’s no silver bullet. But we may be missing out on something fairly simple, a new study found: medical tests.

To quit or not to quit

Researchers from Cardiff University, King’s College London, Queen Mary University of London and the University of Liverpool’s Institute of Translational Medicine studied 4,055 participants aged 50 to 75. They were split into two groups: one that underwent low-dose CT screenings for their lungs, and a control group who didn’t undergo screening.

Right-sided pneumothorax (right side of image) on CT scan of the chest. Image via Clinical Cases / Wikipedia.

The control group reported cessation rates of five percent after two weeks and ten percent after two years. For the CT scan group, rates were ten percent and fifteen percent respectively — that’s a 100% and a 50% increase.

Perhaps most interestingly, this happened regardless of the study results. It was just the medical test itself that persuaded people to give up the nasty habit. Dr Kate Brain, from Cardiff University comments:

‘Our trial shows that CT lung cancer screening offers a teachable moment for smoking cessation among high-risk groups in the UK. We now need evidence about the best ways of integrating lung cancer screening with stop-smoking support, so that services are designed to deliver the maximum health benefits for current and future generations.’

Because this study actually had two groups (a CT scan and a control group), researchers also bypassed the “correlation is not causality” debate. Without this, you could have argued that people who opt for a CT scan care more about their health and are more likely to give up smoking — but this is a significant indication that the CT is causing the increased cessation rate.

It might not seem like much, but considering the sheer damage that smoking does, it’s an avenue that’s worth investigating. Prof John Field, University of Liverpool’s clinical professor of molecular oncology, chief investigator of the UK Lung Cancer Screening Trial believes that this can make a significant difference in tackling lung cancer.

‘The findings of this study dispute the belief that a negative screening result offers a “licence to smoke.” Engaging with lung screening can give smokers an opportunity to access smoking cessation support — at a time when they are likely to be more receptive to offers of help.’

However, CT scans are not easily available in all countries. It can be expensive, it can take months and months of waiting, or it may simply not be available. It would be interesting to see if results are similar for other, perhaps simpler tests.

Journal Reference: Kate Brain et al — Impact of low-dose CT screening on smoking cessation among high-risk participants in the UK Lung Cancer Screening Trial. http://dx.doi.org/10.1136/thoraxjnl-2016-209690

Is the light still on if you close the door? CT-scan looks at the inside of a walnut

CT-Scans (standing for computerized tomography scans) are a series of X-ray images of an object, taken from different angles to produce cross-section images (topographies) of an object. It allows you to look inside most objects without having to cut them open, very handy in fields like medicine or security, to name a few.

They create an image by using Röntgen radiation, more widely known as X-rays — having a much higher energy than visible light, they penetrate through most materials and are captured by a special film on the other side.

They also damage living cells much in the same way as other types of radiation, but for now let’s not think of that and enjoy this strangely relaxing CT of an unopened walnut.

 

Three Egyptian mummies receive CT scans

The Washington University received some unusual patients to scan: three Egyptian mummies.

Curators and radiologists examine the mummy of Pet-Menekh on Sunday, Oct. 12, at Washington University Medical Center. From left are Lisa Çakmak, PhD, assistant curator of ancient art at Saint Louis Art Museum; Karen K. Butler, PhD, associate curator of Washington University’s Mildred Lane Kemper Art Museum; Sanjeev Bhalla, MD, professor of radiology and chief of cardiothoracic imaging at the School of Medicine; and Vincent Mellnick, MD, a Washington University radiologist. Pet-Menekh was scanned in a computerized tomography (CT) scanner at the medical center.

The scanning took place Sunday, Oct. 12, at the Center for Advanced Medicine on the Medical Campus. The mummies, two of which are on long-term loan to the Saint Louis Art Museum from the Kemper Art Museum, were scanned using state-of-the-art CT scans.

CTs and mummies

According to Wikipedia, X-ray computed tomography (x-ray CT) is a technology that uses computer-processed x-rays to produce tomographic images (virtual ‘slices’) of specific areas of the scanned object. Basically, CT scans allow you to see “slices” of the inside of a human body without actually having to cut. It’s not the first time this technique has been used for archaeological purposes.

CT scanners use special equipment that emits a narrow X-ray beam to obtain images from different angles around the body, generating 3-D images that can show the skeleton, tissues and organs. Photo of scan: Robert Boston

The first scan revealed that the mummy still had its brain, heart and lungs; this is pretty unusual, because the heart and the lungs were usually taken out in Ancient Egypt’s mummification. The study also revealed that the mummy had several other objects in its head – but what they are is not clear. It may be something to do with the mummification technique, or it could simply be debris.

The second mummy revealed a much more gruesome truth. It appeared to be significantly shorter than the sarcophagus, and researchers quickly observed that it lacked a head. The head was probably removed when grave robbers ransacked his tomb. They found an item on his chest that may have been a burial amulet missed by grave robbers. They plan to reconstruct the item using 3-D printing.

Karen K. Butler, PhD, associate curator of the Kemper Art Museum, said Pet-Menekh and Henut-Wedjebu were donated to the university in 1896 by Charles Parsons, a St. Louis banker and prominent art collector. Since then, they pretty much became an important part of the University.

The computer adds color to the 3-D images to exaggerate differences in tissue. Photo of scan: Robert Boston

“The mummies have been part of Washington University for more than 100 years,” Butler said. “Faculty from anthropology, classics, art history and archaeology all take students to see them. They are very much part of university life.”

When the old meets the new


The use of CT scans in mummies has been used for over 20 years but the technology is developing all the time. Now, we are able to study them in much more detail, focusing and zooming in on any points of interest; this wouldn’t have been possible a couple of decades ago – and this is really important.

Mummies present archaeologists with an extremely rare opportunity – they are actually time capsules, giving clues of societies and life habits long gone. They can show us not only the life style and spiritual beliefs, but also a number of disease, habits and even general lifestyle. Cutting them open is not an option, as it would not only desecrate the memory of these people, but also possibly destroy unique cultural treasures. This is why non-invasive techniques are used in modern mummy research.

More than 2,000 years after his body was wrapped in bandages, the mummy of Pet-Menekh is eased into a state-of-the-art CT scanner at Washington University Medical Center. Photo: Robert Boston

For example, an indication of ancient lifestyle is artery hardening. Indicators of heart disease have been detected in prior mummy scans, but it’s not clear yet if this is reflective of the elite lifestyle – that is, if people rich enough to be mummified were more likely to suffer from heart disease.

Sanjeev Bhalla, MD, professor of radiology and chief of cardiothoracic imaging lead this study.

“This new CT scanner has higher spatial resolution and quickly can assemble slices in a variety of ways, providing more medical details about the mummies,” Bhalla said.

Logistically, the study was very difficult. They had to be removed from their display cases, and it wasn’t clear if each sarcophagus would fit in the machine, but they ultimately did. Also, there was the problem of being humane. Bhalla viewed this as the most challenging aspect.

“It was very important for us to remember that these were human beings we were scanning,” he said. “We had to do the scanning in an atmosphere of spiritual and physical respect, and with the help of museum staff who acted as a kind of surrogate family for the mummies, we did that.”

 

Penn Research Indentifies Bone Tumor in 120,000-Year-Old Neandertal Rib

The first known case of a bone tumor has been discovered in a Neanderthal who lived about 120,000 years ago in what is now present-day Croatia. The bone samples come from the already famous cave/archaeological site Krapina, which now hosts a Neanderthal Museum.

micro ct scan krapina

MicroCT scan of Krapina 120.71 showing the deterioration of the bone inside the rib neck. (Courtesy of GW Weber, U. Vienna)

Bone tumors are exceptionally rare finds in fossils and archaeological records, with the previous earliest records being approximately 4.000 years old. Even in today’s world, cases of bone tumors are relatively rare.

Using a CT scan and an X-ray, researchers identified a fibrous dysplastic neoplasm – an abnormal bone growth where normal bone is replaced with fibrous bone tissue. Today, this is the most common form of benign bone tumor in humans. The tumor was located on a Neandertal left rib fragment that measured 30 mm (4 ½ inches) long. Judging by the size and shape of the fragment, the Neanderthal was probably a young male.

BoneTumorwebJoining Penn Museum Associate Curator and Paleoanthropologist Janet Monge on the research team were Morrie Kricun, Department of Radiology, University of Pennsylvania; Jakov Radovcic and Davorka Radovcic, Croatian Natural History Museum; Alan Mann, Department of Anthropology, Princeton University, and David Frayer, Department of Anthropology, University of Kansas. The confirmation of this tumor, Monge claims, has significant implications for archaeologists, anthropologists and geneticists studying the connections between Neanderthals and humans.

“This tumor may provide another link between Neandertals and modern peoples, links currently being reinforced with genetic and archaeological evidence. Part of our ancestry is indeed with Neandertals—we grow the same way in our bones and teeth and share the same diseases.”

Full study: Fibrous Dysplasia in a 120,000+ Year Old Neandertal from Krapina, Croatia

World’s oldest tootache revealed in ancient reptile fossils

The Labidosaurus Hamatus jaw examined

Paleontologists turned into dentists after an examination of the fossilized jaw of a reptile from the Paleozoic era revealed what’s considered to be the world’s oldest tootache.

Dated back 275 million years ago, the Oklahoma found Labidosaurus hamatus must have had some serious issues with its sugar tooth, as researchers  observed missing teeth and  eroded bones in its jaw, which poissed them to dwell a bit further. Led by Robert Reisz, the chair of the Department of Biology at the University of Toronto Mississauga, scientists decided to investigate further with a CT-scan – they  soon found evidence of a major infection that had caused the loss of several teeth and a massive abscess.

“Not only does this fossil extend our understanding of dental disease, it reveals the advantages and disadvantages that certain creatures faced as their teeth evolved to feed on both meat and plants,” said lead researcher Robert Reisz. “In this case, as with humans, it may have increased their susceptibility to oral infections.”

What apparently happened, researchers conclude, is that the reptile lost a tooth, which consequently became a hole, and through that hole a heck load of bacteria flooded and extended itself to other adjacent healthy teeth. This is exactly what Reisz was pointing out, since it shows how important evolution influenced this particular case. Because the Labidosaurus’ diet was plant based, ergo a lot of chewing was involved, it gradually evolved from the primivitive dental setup in which teeth were loosely attached to the jaws and continuously replaced (see sharks) to teeth that were strongly attached to the jaw, with little or no tooth replacement.

The downside to this, however, is pretty evident as outlined, which in way explains why humans are also very susceptible to dental infections if a parallel is to be made.

“Our findings suggest that our own human system of having just two sets of teeth, baby and permanent, although of obvious advantage because of its ability to chew and process many different types of food, is more susceptible to infection than that of our distant ancestors that had a continuous cycle of tooth replacement,” Reisz said.

The study is detailed online in the journal Naturwissenschaften — The Science of Nature.