Scintillator Phosphors for Medical Imaging

Steven J. Duclos

doi:10.1149/2.f07982if

Scintillator Phosphors for Medical Imaging

The Electrochemical Society Interface ◽

10.1149/2.f07982if ◽

1998 ◽

Vol 7 (2) ◽

pp. 34-38

Author(s):

Steven J. Duclos

Keyword(s):

Medical Imaging ◽

Visible Light ◽

Medical Diagnostics ◽

Turn Of The Century ◽

High Density ◽

Luminescent Materials ◽

X Rays ◽

Photomultiplier Tubes ◽

Electrical Signals ◽

Charge Coupled Devices

Scintillators are high density luminescent materials that convert X-rays to visible light. These materials have been used since the turn of the century to dramatically enhance the sensitivity of film cartridges used in medical diagnostics. Coupling scintillators to photodiodes, charge coupled devices (CCDs), and photomultiplier tubes (PMTs) is an efficient way to convert X-rays to electrical signals.

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Studies of metaphase chromosomes in the scanning transmission x-ray microscope: Image fidelity, radiation damage and specimen preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129826 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1038-1039

Author(s):

Shawn Williams ◽

Xiaodong Zhang ◽

Susan Lamm ◽

Jack Van’t Hof

Keyword(s):

Visible Light ◽

Radiation Damage ◽

Cross Section ◽

Imaging Techniques ◽

Dose Range ◽

Specimen Preparation ◽

X Rays ◽

Metaphase Chromosomes ◽

X Ray ◽

Scanning Transmission

The Scanning Transmission X-ray Microscope (STXM) is well suited for investigating metaphase chromosome structure. The absorption cross-section of soft x-rays having energies between the carbon and oxygen K edges (284 - 531 eV) is 6 - 9.5 times greater for organic specimens than for water, which permits one to examine unstained, wet biological specimens with resolution superior to that attainable using visible light. The attenuation length of the x-rays is suitable for imaging micron thick specimens without sectioning. This large difference in cross-section yields good specimen contrast, so that fewer soft x-rays than electrons are required to image wet biological specimens at a given resolution. But most imaging techniques delivering better resolution than visible light produce radiation damage. Soft x-rays are known to be very effective in damaging biological specimens. The STXM is constructed to minimize specimen dose, but it is important to measure the actual damage induced as a function of dose in order to determine the dose range within which radiation damage does not compromise image quality.

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X-ray Microscopy in your Lab

Microscopy Today ◽

10.1017/s1551929513000163 ◽

2013 ◽

Vol 21 (2) ◽

pp. 7-7

Author(s):

Charles Lyman

Keyword(s):

Grain Size ◽

Point Source ◽

Visible Light ◽

Light Microscope ◽

Construction Materials ◽

X Rays ◽

X Ray ◽

Projection Images ◽

Straight Lines

Using X rays to produce magnified images of objects has been a goal for 150 years. Ever since Ernst Abbe declared in 1873 that light microscope resolution was limited by the wavelength of light, the search was on for a microscopy medium with a wavelength shorter than visible light (<500 nm). When Roentgen discovered X rays in 1895, it was thought that the new medium may have been found. Soon it was clear, however, that it was not easy to construct a physical lens for X rays because the rays penetrated all lens construction materials. X-ray “radiography images” of a few times magnification were possible but only as projection images, formed as X rays from millimeter-sized sources traveled in straight lines through the specimen to be captured on film. Unfortunately, even in the best cases, useful magnification was limited by the relatively large “point source” of X rays and the large grain size of X-ray film (both about 0.1–1.0 mm).

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Nicht nur Slapstick: Stummfilme als unterschätzte Zeugen der Medizingeschichte

DMW - Deutsche Medizinische Wochenschrift ◽

10.1055/a-1160-1493 ◽

2020 ◽

Vol 145 (25) ◽

pp. 1818-1827

Author(s):

Dennis Henkel ◽

Eelco M. Wijdicks ◽

Axel Karenberg

Keyword(s):

Medical Profession ◽

Silent Film ◽

Turn Of The Century ◽

Short Film ◽

X Rays ◽

Silent Cinema ◽

Feature Films ◽

Illegal Abortion ◽

Art Form ◽

Short Films

AbstractMedicine in silent film has a long history. Although the silent era in cinema was dominated by burlesques (using escaped “lunatics”) a number of themes emerged after systematic review. The cinematic representation of medicine coincided with the discovery of X-rays. During this “roentgenomania”, short films were produced showing groundbreaking X-ray images, which fitted perfectly into needs of dramatic cinema. But soon the “cinema of narration” evolved: Starting just after the turn of the century, the short film “The Country Doctor” was able to address complex interplay between duties and limitations of the medical profession. This was followed by numerous feature films on infectious diseases, which often used tuberculosis as a centerpiece of its story. Directors often took advantage of the well-known stereotype of the omnipotent physician. But in certain medical fields, such as psychiatry or surgery, a more ambivalent figure of the doctor was portrayed, f. e. in “Hands of Orlac” (1924). Silent cinema also offered interesting ideas on the healing powers of the medium itself: in “The Mystery of the Kador Cliffs” (1912) a film screening could cure the patient of fears after reenactment. Finally, a closer look at the early era of film echoes how social conflicts where dramatized, especially in the case of nationwide birth control. How illegal abortion kept the society on its edge, was most clearly shown in the adaption of the scandalous play “Cyankali” (1930).In addition to discussing various topics in the cinematic representation of medicine, this brief overview shows that silent movies were a new and true art form, representing an exceptional resource for historians of film and medicine.

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HEALTH HAZARDS FROM MOBILE TOWER: A REVIEW

10.36106/gjra/8410069 ◽

2021 ◽

pp. 78-79

Author(s):

Avni KP Skandhan ◽

Skandhan KP ◽

Prasad BS

Keyword(s):

Ionizing Radiation ◽

Ultraviolet Radiation ◽

Visible Light ◽

Mobile Phone ◽

Gamma Rays ◽

Health Hazards ◽

X Rays ◽

Radio Waves ◽

Fm Radio ◽

Smart Tv

Our knowledge on X-rays, gamma rays and ultraviolet radiation is ionising . Non-ionising gadget radiation is from Mobile Phone, Laptop, Tablet Smart TV etc. and harmful radiations is from mobile towers . FM radio waves, Microwaves, Visible light are also other forms of non-ionizing radiation.

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4113. Two-phase high-density charge coupled devices fabricated by electron-beam lithography. (USA)

Vacuum ◽

10.1016/0042-207x(79)90223-9 ◽

1979 ◽

Vol 29 (8-9) ◽

pp. 329

Keyword(s):

Electron Beam ◽

Electron Beam Lithography ◽

High Density ◽

Two Phase ◽

Charge Coupled Devices

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New photomultiplier tubes for medical imaging

IEEE Transactions on Nuclear Science ◽

10.1109/23.34608 ◽

1989 ◽

Vol 36 (1) ◽

pp. 1078-1083 ◽

Cited By ~ 13

Author(s):

T. Hayashi

Keyword(s):

Medical Imaging ◽

Photomultiplier Tubes

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Electrical Impedance Tomography (EIT)

Research Developments in Computer Vision and Image Processing - Advances in Computational Intelligence and Robotics ◽

10.4018/978-1-4666-4558-5.ch013 ◽

2014 ◽

pp. 235-273 ◽

Cited By ~ 5

Author(s):

Tushar Kanti Bera ◽

J. Nagaraju

Keyword(s):

Medical Imaging ◽

Electrical Impedance Tomography ◽

Electrical Impedance ◽

Optical Tomography ◽

Body Part ◽

Imaging Modalities ◽

X Rays ◽

Science And Engineering ◽

Impedance Tomography ◽

Anatomy And Physiology

Looking into the human body is very essential not only for studying the anatomy and physiology, but also for diagnosing a disease or illness. Doctors always try to visualize an organ or body part in order to study its physiological and anatomical status for understanding and/or treating its illness. This necessity introduced the diagnostic tool called medical imaging. The era of medical imaging started in 1895, when Roentgen discovered the magical powerful invisible rays called X-rays. Gradually the medical imaging introduced X-Ray CT, Gamma Camera, PET, SPECT, MRI, USG. Recently medical imaging field is enriched with comparatively newer tomographic imaging modalities like Electrical Impedance Tomography (EIT), Diffuse Optical Tomography (DOT), Optical Coherence Tomography (OCT), and Photoacaustic Tomography (PAT). The EIT has been extensively researched in different fields of science and engineering due to its several advantages. This chapter will present a brief review on the available medical imaging modalities and focus on the need of an alternating method. EIT will be discussed with its physical and mathematical aspects, potentials, and challenges.

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