Cedar-Sinai the technology being used to fail. In


The factors leading to radiation
overdose at Cedar-Sinai

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!

order now

Alipayman Ramazani


of engineering

Upon Tyne, England

[email protected]



Abstract Given the rapid improvements in technology and machinery that
are used in health Centre’s across the globe, companies face huge pressures to
develop and engineer new and more innovative products, with the aim of aiding
hospitals and professionals to be more efficient when examining and diagnosing
patients. However, it should not come as a huge surprise for the technology
being used to fail. In this article, I will be investigating the main causes
that lead to 206 patients at Cedar-Sinai health center being examined for
potential stroke, where new CT machines recently installed was used that lead
to these patients being to a dangerous dose of radiation eight times the
prescribed limit, also I will be outlining the measures which are now in place
to reduce such incidents happening in the future.



Introduction Clinical medicine has without doubt been revolutionized with the aid
of medical imaging. Modern-day imaging continues to provide detail and accuracy
beyond believe, reflected in reduced hospital stays, more effective surgical
treatments, improved treatment of cancer, elimination of exploratory surgery
and treatment of stroke patients just to list a few.


first Computed tomography scanner developed by Godfrey Hounsfield backed by EMI
Central Research Laboratories based in Hayes, West London, produced its first
image on the 1st October 1971 at Atkinson Morley’s Hospital, located
in London, England. The image produced was an 80 x 80 matrix, taking roughly 5
minutes to generate by the prototype scanner, however in today’s technology, CT
scanners are able to produce images with a 1024 x 1024 matrix from a few
million data points, in a few seconds, making it a crucial and valuable asset
to the medical centers around the world.


1,5 A computed
tomography fires narrow beams of x-rays at a patient, while rotating around the
body, this results in signals which can be detected by the x-ray detectors
located directly opposite the x-ray beams and is processed by the computer to
generate a cross-sectional “slices ” of the body part, given the term
tomographic images, these images contain a greater amount of detail than that
found in x-ray images making them very useful tools to physicians, the slices
produced are then “stacked” in the order produced by the machines computer to
produce a three dimensional image showing the inner structures as you would see
if you were to physically perform a surgical operation, so the doctors can
identify and locate any abnormalities or damage to the patient’s internal


Overtime CT
scanners have become far more advanced the first clinical CT scanner was
dedicated to only producing head images only, as the effectiveness of these
machines became more recognized around the world, in less than 6 years and
there are about 6000 Computed tomography scanners installed worldwide, and were
able to take whole body images.


During its
45-year history, Computed tomography functions at a far greater speed, and
improvement in resolution and patient comfort. As Computed tomography are able
to produce images faster, more anatomy can be scanned in far less time than
before this is important as it helps to eliminate any artefacts

that can arise
from the patient motion.


The CT machines
used to produce these images require the technicians to be fully trained in
operating them and understand the safe limits of radiation to which patients
can be exposed to, because of the dangerously high dosage of radiation these
machines are capable and could be programmed to emit. But during an
eighteen-month period at Cedars-Sinai Medical center, where 206 patients were
exposed to eight times the normal radiation dose, and 20% directly to their



reports by IMV (Medical information division) in figure 2 shows the
rapid increase in the use of CT imaging in the United states, the radiation
exposure associated with them over the last decade outline the dangers which
could arise, clearly shown in the radiation overdose incident that took place
at Cedar-Sinai beginning February 2008 and after 18 months, for such a major
incident to occur indicates there are multiple causes which can be classified
in two very different categories being the Medical Centre and the manufactures.


Many sources
such as the ‘New York Times’ related the main cause to mainly human ‘error’,
this came about as a result of the
hospital started to use a new protocol for a specialized form of scan which was believed to provide doctors with more useful
information in their effort to treat stroke patients. So that meant resetting
the CT machines to be able to override the pre-programmed instructions which
accompanied the scanner when it was first installed.

Once these new
instructions were programmed into the machines, they were essentially locked
in. The machine was used for other types of scans which the ‘error’ did not


The 10’Swiss cheese’ model of organizational accidents, is an
excellent procedure which can be used to reduce the likelihood of accidents
occurring in large organizations, the model is built on the idea of having
barriers at each step in a process to eliminate any potential error before the
final outcome, so in an event of a major error to occur all the holes will have
to line up this would be the case in a flawed system that would allow an error
or mistake at the beginning to reach and affect the outcome. So, to reduce the
chances of an error effecting the outcome the more cheese slices used the
smaller the chances of errors and also the smaller the holes the better as
smaller holes could imply a more detailed analysis at each stage of the process
that would ultimately catch or even stop the error becoming an accident.


The incident at Cedar-Sinai could be linked to the system failing,
because of the difficulty in detecting errors during the process of CT imaging,
unlike errors that lead to physically visible outcomes, that can easily be found,
an example being a plane engine failing due to internal faults causing it to
explode during the testing period, can be investigated quicker and
instantaneous safe guarding actions could be taken to prevent any casualties,
however with CT scanners the accidents could take years before they are
detected, so it’s crucial the system in place has virtually no flaws and any
human errors don’t become accidents. This is where the problem starts, 9
‘INSIDE SCIENCE’ reported that Medical Centre Cedar Sinai were not accredited
by American College of Radiology, who offers guidelines for standards and
protocols, and obviously the process used for CT scans at Cedar-Sinai was not
effective in preventing errors progressing through its successive layers of


The system as a
whole failed because individual parts that make it did not carry out their
roles effectively and this could be linked to the team, management,


technologist has responsibility to ensure patients under their care are not
exposed to dangerous levels of radiation (ARRT Code of Ethics). This implies
practicing with integrity, only using equipment that is serviced properly and
maintained locally or by vendor.


Although in the
investigation carried out by the FDA and GE healthcare the product
manufacturers, they did not find any faults with the machines itself, but
recommendations included there could have been an improvement in safety
features built in the scanners, one of the obvious features the GE scanners had
is a feature called automatic exposure control. The feature automatically
adjusts the radiation dose according to a person’s body part and their size so
smaller children receive less radiation, because their body is growing and
radiation is more likely to cause cancer, rather than using a pre-determined
radiation level, the aim of the feature being to reduce the doses. But when the
feature is used with certain machine settings which governed image clarity, the
effect was to drastically increase the radiation dose delivered to the

scanners have a feature called automatic exposure control. It automatically
adjusts the radiation dose according to a person’s size and the body part being
scanned, rather than using a fixed, predetermined radiation level. Its intent
is to lower radiation doses. But when used in combination with certain machine
settings that govern image clarity, its effect was to significantly raise the
dose of radiation delivered to a patient.

to Cedar-Sinai the GE manual as part of the CT scanner failed to state the
feature was not designed to be used in brain scans. And the GE trainers failed
to fully explain the feature.

After many
high-profile incidents of radiation overdose leading to patient harm during CT
imaging, it’s not a secret that ionizing radiation used by medical imaging have
many harmful effects associated to them, but their benefits to medical centers
far outweigh the risks posed. However due to the heavily reported incident, at
cedar-Sinai. National organizations such as the Medical Imaging and Technology
Alliance, American College of Radiology and the joint Commission have devised
various standards linked to radiation safety.


One of the
changes coming in the form of a SB 1237 in 2010 to ensure radiation dose are monitored
better for CT scans. The law going into effect from July 1st, 2012
involve a number of components:

Hospitals and
clinics are required by law to record dose of every procedure performed using a
CT scanner, Especially volume of volume of CT dose index. And the dose length

The dose
information has to be sent to the Picture Archiving and Communication System
(PAC) when possible also the information must be part of the patient’s report
helping to determine their radiation dose received over their lifetime.

In an event
where patents receive excessive dose of radiation must be reported to the
California Department of Public Health (CDPH); and radiation physicist to
annually verify dose levels annually.



Conclusion during an
18-month period 206 suspected stroke patients underwent CT scans, as a result
of resetting the default settings on the machine, physicians being under the
assumption that increasing the radiation dosage to supply eight times the
recommended for the specific scan on the machines, believing it could provide
highly detailed images, as the settings on the CT scanner was changed to
reflect their theory, lead to the machine being locked in with the new
settings. Both the manufactures and Cedar-Sinai could have taken steps to help
prevent the accident occurring as ‘human error’ is essentially unavoidable, in
such high pressure and complexity situations.


After patients
started reporting hair loss, the Health care center began their own
investigation which found the incident was caused by the CT machine and
therefore investigation carried by the Food and Drug Administration (FDA)
concluded the error was due to operator error, and the FDA issued
recommendations to both the manufactures and Cedar-Sinai to help tackle such
incidents developing in the future.


In my opinion,
the main cause for the incident came about because there were not enough safety
features that could have prevented the incident and the lack of regular machine
checks and failure to record the radiation dose patients were being scanned
with as one of the primary reasons the incident went unnoticed for 18 months, I
cannot find a reason to why a product that is capable of providing dangerous
levels of radiation directly at specific body parts allows users to make
changes, or only allow lead technologists and supervisors access to changing
settings on the machine, it’s important that users are not fully locked out of
the system as that’s impractical, considering the number of CT scans carried
out in health centers users should be allowed to make changes but not any that
could pose a risk to the patient, as well as having warnings built in the
system to alert users of changes to the protocols that could lead to


I believe the
changes and new laws which are implemented as a direct result of the incident
at cedar Sinai will help reduce the incidents occurring in the future but I
believe these laws will only be effective if the medical centers are educated
in maintaining the CT machines, and the new technology used in them must be
explained to and be part of the manual issued to the medical centers
furthermore the manufacturers should perform frequent machine tests to test for
any flaws or changes made to the system.






1  https://www.radiologyinfo.org/en/info.cfm?pg=safety-hiw_04

Accessed on 9th
December 2017


2 http://www.impactscan.org/CThistory.htm

Accessed on 9th
December 2017


3 http://www.mcgeorge.edu/Documents/Publications/08_HealthandSafetyMaster4-5-11.pdf

produced by health and safety author 
Christopher Braniff

4 https://www.medpagetoday.com/Radiology/DiagnosticRadiology/16455



5 https://www.nibib.nih.gov/science-education/science-topics/computed-tomography-ct


6 http://www.imaginis.com/ct-scan/brief-history-of-ct


7 http://www.nejm.org/doi/full/10.1056/NEJMra072149#t=article


8 http://www.imvinfo.com/user/documents/content_documents/nws_rad/MS_CT_DSandTOC.pdf


9 https://www.insidescience.org/news/medical-physicists-ct-scans-safe


10  “Swiss Cheese” Model – James Reason, 1990.  The book
reference is: Reason, J. (1990) Human Error. Cambridge: University Press,


11 http://patientsafetyed.duhs.duke.edu/module_e/swiss_cheese.html


12 http://www.thedoctorwillseeyounow.com/content/stroke/art3145.html


13 https://www.arrt.org/docs/default-source/Governing-Documents/arrt-standards-of-ethics.pdf?sfvrsn=12


14 https://www.itnonline.com/article/states-making-difference-radiation-safety

accessed on 13 December 2017.





I'm Alfred!

Would you like to get a custom essay? How about receiving a customized one?

Check it out