teeth featured

source: animalnewyork

No, these aren’t those way-trippy black light dorm posters they sell at Spencer’s Gifts. They’re actually software-enhanced medical images of teeth, rotting teeth, the inside of a left nostril, heart valves, the brain’s fourth ventricle, stress lines in the skull, and cranial blood vessels; respectively. They just happen to be really, really, mind-meltingly psychedelic.

Hong-Kong based radiologist Dr. Kai-hung Fung had no intention of producing “art” when he generated these images. The project came about purely by accident when he was asked to generate complex 3-D anatomical images for surgeons to visually prepare themselves before operating. He stacked up CT scans of different organ “slices” shot from different angles, indicating changes in depth by using different colors and contour lines.

According to Slate, “Dr. Fung’s ’4-D visualizations’ (short 3-D videos) aid surgeons by ‘showing changing perspectives and relative relationships of various anatomical structures … [matching] the surgical or endoscopic field of view.’”. Don’t you love when things that are sweet to stare at also benefit society?

Dr. Fung is currently working on producing 3-D CT images of flowers and biological specimens.
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source: 3dvisacchkclacuk

Tomography Art by Kai-hung Fung

Kai-hung Fung is a medical doctor and a specialist in diagnostic radiology at Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR, China. He also applies radiology to visual arts. Using his experience of 3D Computer Tomography (CT) for medical diagnosis, he creates artistic images of the human body based on data acquired from CT scanners.

Dr Kai-hung Fung is a winner of the 5th annual International Science and Engineering Visualization Challenge 2007, sponsored by Science, the journal of the American Association for the Advancement of Science (AAAS), and the National Science Foundation (NSF). His entry, entitled What lies behind our nose?, has been awarded the first prize (tie) in the photography category. It was created using 3D computed tomography (CT) of the human nose and paranasal sinuses, and a special rendering method developed by Dr Kai-hung Fung, known as ‘rainbow technique’. He is also interested in developing stereoscopic artwork using 3D CT.

The ‘rainbow technique’ is a new method of art representation using contour lines to define 3D space or object, each contour line being in the form of a colourful rainbow. Similar to pointillism, this new concept of colour representation vitalize the artwork transforming it into one that sparkle with colours. Due to its complexity, it is only made possible with modern computer technology.

My interest in using 3D computed tomography (CT) as a tool for creative art originated just a few years ago, perhaps around 2003 when we acquired a Toshiba 16-slice multi-detector row CT in our hospital for medical imaging. With this new line of CT scanner, high resolution reconstructed 3D images can be obtained due to the improved performance of the CT scanner (thinner slices, faster scanning time) coupled with availability of more powerful computer workstation and more sophisticated software for 3D reconstruction. We used Vitrea®2 software by Vital Images, Inc.

Although most people are quite satisfied with the preset range of colour rendering provided by the 3D software (usually involving a limited choice of colours), I tried to explore how I can utilize the full colour spectrum in my 3D rendering. With perseverance and a lot of luck, I was able to realise the concept of the ‘rainbow technique’ and produce 3D CT artworks successfully with this technique in 2005.

In fact 3D image in CT is formed by staking together hundreds of very thin slices (about 0.5 to 1 mm in thickness). Stepping artefacts are inherent in this staking process particularly along sloping edges. The stepping artefacts will show up as contour lines in the 3D object only at certain critical settings.

The CT image in fact is a plot of the CT values in small picture elements called voxels. The usual rendering method is to apply a grey-scale to these values to form the image. The grey-scale can be manipulated by shifting the window level and window width in CT just like changing the gamma and latitude in a film. The manipulation could help to show different structures (e.g. air, fat, soft tissue or bone) with different CT values.

In colour 3D rendering, different colour spectra are applied instead of a grey scale. Before applying the colour, an algorithm in the form of a curve can be applied to bias the colour rendering towards specific CT range.

So by adjusting the window level and window width together with the use of a very narrow band width algorithm, a critical level could be reached for structures showing specific CT values so that the surface of the 3D structure starts to break up into contour lines. Applying a rainbow spectrum at this point produces the ‘rainbow technique’.

The rainbow effect is particularly noticeable in strongly curved surface and at close-up. It adds to the 3D perception by showing up as contour lines instead of smooth surface with gradation. Furthermore it acts like a shutter blind instead of a curtain in separating 3D space. Structures behind can be clearly seen instead of blurred. Those structures that have CT values outside the critical range will be rendered in the usual way, giving additional room for artistic creativity. The rainbow effect can also be perceived stereoscopically in virtual reality if stereoscopic pair of images is obtained and viewed with appropriate tools such as a stereoscope.

Of course, apart from the ‘rainbow technique’ there are many ways in rendering the 3D CT e.g. using semi-transparency to produce artistic effect. However, in my opinion the ‘rainbow technique’ is particularly appealing aesthetically.
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source: mdig

Além de médico especialista em radiologia, o doutor Kai-hung Fung é “o cara” na chamada “arte tomográfica”. Emprega o TAC (tomografia axial computarizada) não só para observar o organismo senão para fazer verdadeiras peças de arte, em três e quatro dimensões. Sua principal inovação: o uso da chamada “técnica arco íris”, com a qual modifica as cores da tomografia para lhe conferir maior valor artístico.

O que tem debaixo do nariz?
Uma das obras mais conhecidas do artista. Esta imagem ganhou o primeiro prêmio do Quinto Concurso Internacional de Visualização de Ciência e Engenharia, patrocinado pela revista “Science”.

Umbigo
Para além da psicodelia que pode emergir desta imagem, nesta ocasião o TAC foi empregado para mostrar o umbigo. É um claro exemplo da “técnica arco íris”, criada por este médico.

Dentes
Kai-hung Fung mostra assim a mandíbula de um humano, vista pelas gengivas dos dentes de baixo. Os dentes aparecem destacados em violeta, as raízes em azul e os ossos em verde.

Curvas na orelha
Esta imagem em 3D, feita graças a um TAC, mostra a parte central do ouvido externo direito.

Um ovo fertilizado
Em laranja, o esqueleto de um embrião de galinha dentro de seu ovo. Além da coluna, que se vê claramente, a imagem deixa intuir a cabeça, o bico e os ossos das pernas.