Abstract:
:A bright flash of light is emitted by the plasma formed at the focus of an ophthalmic Nd: YAG laser. The purpose of this investigation is to determine whether the plasma flash constitutes a hazard to the operator. The intensity of the flash at the slit lamp eyepiece was measured and the experimentally derived value was verified by independent calculation. For hazard assessment purposes, the concept of a spectrally weighted maximum permissible exposure (MPE) is described in the paper. Based on the MPE and our measurements and calculations our conclusion is that viewing the flash in a patient's eye through the microscope would not be considered hazardous to the operator. In contrast, during technical procedures, targets in air are used to produce a plasma and in this situation eye protection is recommended when viewing the flash through the microscope.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Moseley H,Allan Ddoi
10.1088/0031-9155/32/9/009subject
Has Abstractpub_date
1987-09-01 00:00:00pages
1159-66issue
9eissn
0031-9155issn
1361-6560journal_volume
32pub_type
杂志文章abstract::A multicentre phase II trial of stereotactic body radiotherapy for T1N0M0 non-small cell lung cancer was initiated in Japan as the Japan Clinical Oncology Group trial (JCOG0403). Before starting the trial, a decision was made to evaluate the treatment machine and treatment planning in participating institutions to min...
journal_title:Physics in medicine and biology
pub_type: 杂志文章,多中心研究
doi:10.1088/0031-9155/51/21/002
更新日期:2006-11-07 00:00:00
abstract::Andreo and Benmakhlouf (2017 Phys. Med. Biol. 62 1518-32) have disputed a finding of Scott et al (2012 Phys. Med. Biol. 57 4461-76) that the variation with field-size of the response of small ion chambers and solid-state dosimeters in small megavoltage photon radiation fields can largely be attributed to density. Furt...
journal_title:Physics in medicine and biology
pub_type: 评论,杂志文章
doi:10.1088/1361-6560/aae0e4
更新日期:2018-10-03 00:00:00
abstract::We recently started orthogonal two-port carbon ion therapy for choroidal melanoma with the intent to reduce the incidence of radiation complications that occur with mono-port therapy. Treatment planning techniques involving therapeutic beam characteristics are described here. The vertical (140 MeV/u) and horizontal (1...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/17/016
更新日期:2007-09-07 00:00:00
abstract::Factors influencing the precision of measuring changes in the calcium content of sections of bone, including vertebrae, using reactor neutrons for partial body in vivo activation analysis have been examined and quantified. These factors include (a) the choice of incidient neutron spectrum, (b) the uniformity of activa...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/20/1/007
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/35/9/009
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/55/3/023
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/55/8/N02
更新日期:2010-04-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/abb7c1
更新日期:2020-09-11 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/60/18/7165
更新日期:2015-09-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/28/12/005
更新日期:1983-12-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/56/13/011
更新日期:2011-07-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/57/23/8099
更新日期:2012-12-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/42/7/005
更新日期:1997-07-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/61/11/4141
更新日期:2016-06-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa5452
更新日期:2017-04-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/60/10/4033
更新日期:2015-05-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/13/002
更新日期:2007-07-07 00:00:00
abstract::A water calorimeter has been used for the direct measurement of absorbed dose to water in a d(15) + Be neutron beam. The absorbed dose measured with the calorimeter was compared with that measured with an Exradin ionisation chamber, constructed of A-150 plastic. The doses measured by the ionisation chamber were calcul...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/31/4/005
更新日期:1986-04-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/55/22/007
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journal_title:Physics in medicine and biology
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:2006-03-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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abstract::A new mathematical model of the head has been constructed from a set of serial MRI slices from one subject. Finite-difference time-domain (FDTD) calculations of the specific energy absorption rate (SAR) have been performed on this model with a 2 mm resolution for a generic mobile communication transceiver represented ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/39/10/003
更新日期:1994-10-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:1991-08-01 00:00:00
abstract::A micro-multileaf collimator (microMLC) for stereotactic radiosurgery is used for determination of the spatial intensity distribution of the photon source of a linear accelerator. The method is based on grid field dose measurements using film dosimetry and is easy to perform. Since the microMLC does not allow 'direct'...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:2003-08-07 00:00:00
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journal_title:Physics in medicine and biology
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更新日期:1985-02-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:1980-09-01 00:00:00
abstract::Online adaptive radiation therapy (ART) based on real-time magnetic resonance imaging represents a paradigm-changing treatment scheme. However, conventional quality assurance (QA) methods based on phantom measurements are not feasible with the patient on the treatment couch. The purpose of this work is to develop a fa...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa6e38
更新日期:2017-06-21 00:00:00