Transcript gynecology-chapter-33-mri-chapter-35-artifacts-plus-patient-care

Chapters 33, 35, and Patient Care
33: The Role of Magnetic Resonance Imaging in the Evaluation of
Gynecologic Disease
35: Artifacts, Pitfalls
Patient Care
Holdorf
ULTRASOUND OF THE FEMALE
PELVIS
Contents
 MRI and Gynecology
 Artifacts
 Patient Care
MRI and Gynecology
 MRI is a relatively new technology, which has
been in use for little more than 30 years
(compared with over 110 years for X-ray
radiography).
 The first MR Image was published in 1973 and
the first study performed on a human took
place on July 3, 1977.
 MRI is used to image every part of the body,
but is particularly useful in neurological
conditions, disorders of the muscles and
joints, for evaluating tumors and showing
abnormalities in the heart and blood vessels
Applications
 In clinical practice, MRI is used to distinguish
pathologic tissue (such as a brain tumor) from
normal tissue.
 One advantage of an MRI scan is that it is
harmless to the patient. It uses strong
magnetic fields and non-ionizing radiation in
the radio frequency range.
 Compare this to CT scans and traditional Xrays which involve doses of ionizing radiation
and may increase the risk of malignancy,
especially in a fetus.
 While CT provides good spatial resolution
(the ability to distinguish two structures an
arbitrarily small distance from each other as
separate), MRI provides comparable
resolution with far better contrast resolution
(the ability to distinguish the differences
between two arbitrarily similar but not
identical tissues).
 MRI can generate cross-sectional images in
any plane (including oblique planes).
 In the past, CT was limited to acquiring
images in the axial (or near axial) plane. The
scans used to be called Computed Axial
Tomography scans (CAT scans).
 However, the development of multi-detector
CT scanners allows the CT scanner to
produce data that can be retrospectively
reconstructed in any plane with minimal loss
of image quality.
MRI is also best suited for cases when a patient
is to undergo the exam several times
successively in the short term, because, unlike
CT, it does not expose the patient to the
hazards of ionizing radiation.
Projectile or missile effect
As a result of the very high strength of the
magnetic field needed to produce scans
(frequently up to 60,000 times the earth's own
magnetic field effects), there are several
incidental safety issues addressed in MRI
facilities.
Missile-effect accidents, where ferromagnetic
objects are attracted to the center of the
magnet, have resulted in injury and death
In order to help reduce the risks of projectile
accidents, ferrous objects and devices are
typically prohibited in proximity to the MRI
scanner, with non-ferromagnetic versions of
many tools and devices typically retained by the
scanning facility.
Patients undergoing MRI examinations are
required to remove all metallic objects, often by
changing into a gown or scrubs.
Pregnancy
No effects of MRI on the fetus have been
demonstrated. In particular, MRI avoids the use
of ionizing radiation, to which the fetus is
particularly sensitive.
However, as a precaution, current guidelines
recommend that pregnant women undergo
MRI only when essential.
This is particularly the case during the first
trimester of pregnancy, as organogenesis takes
place during this period.
The concerns in pregnancy are the same as for MRI
in general, but the fetus may be more sensitive to
the effects—particularly to heating and to noise.
However, one additional concern is the use of
contrast agents; gadolinium compounds are known
to cross the placenta and enter the fetal
bloodstream, and it is recommended that their use
be avoided.
Despite these concerns, MRI is rapidly growing
in importance as a way of diagnosing and
monitoring congenital defects of the fetus.
MRI without contrast agents is the imaging
mode of choice for pre-surgical, in-utero
diagnosis and evaluation of fetal tumors,
primarily teratomas, facilitating open fetal
surgery, other fetal interventions, and planning
for procedures to safely deliver and treat
babies whose defects would otherwise be fatal.
For babies and young children chemical
sedation or general anesthesia are the norm, as
these subjects cannot be instructed to hold still
during the scanning session.
Obese patients and pregnant women may find
the MRI machine to be a tight fit. Pregnant
women may also have difficulty lying on their
backs for an hour or more without moving.
Cervical Cancer/ Pretherapeutic evaluation of the extent of disease
The pre-treatment evaluation of patients with
cervical cancer includes physical examination,
chest radiography, and intravenous urography
(IVU) or cross-sectional imaging (computed
tomography scanning or magnetic resonance
imaging .)
In early-stage disease with a small tumor
confined to the cervix, IVU and cross-sectional
imaging are not routinely performed because of
their relatively low yield.
MRI has excellent soft-tissue contrast
resolution, which exceeds that of CT scanning
and ultrasonography.
Consequently, MRI is significantly more
valuable than CT and US in the assessment of
the size of the tumor, the depth of the cervical
invasion, and the extent of the disease (direct
invasion of the parametrium, pelvic sidewall,
bladder, or rectum)
CT scanning and MRI are approximately
equivalent, and both are significantly superior
to US, in the detection of enlarged lymph nodes
Overall, CT scanning and MRI are accurate
staging modalities for cervical cancer
Furthermore, US is not suited for staging of the
full extent of the tumor spread because of the
inability of this technique to adequately depict
all the potential sites of metastasis or the
anatomic regions that contain lymph nodes.
Artifacts
Pelvis, gravid, and non-gravid uterus
 Soft-tissue mass vs. urine stream
 Bowel within the pelvis
 Bowel-gas artifact
 Bowel vs. large pelvic cyst
 Dilated fallopian tubes simulating ovarian cysts
 Normal sonogram vs. Ovarian torsion
 Normal prominent bowel vs. ovaries or Paraovarian masses
 Bowel simulating an ovarian cystic teratomas
 Pregnancy with a co-existent ovarian carcinoma
 Nabothian cysts vs. a low-implanted gestational sac
 Anteflexed uterus vs. mass on transverse view
 Myomatous disease vs. a hydatidiform mole
 Broad ligament myoma vs. an ovarian lesion
Artifacts homework
Bring in the following artifacts/structure classifications as they
pertain to gynecology:
 Posterior acoustic enhancement
 Edge shadowing
 Reverberation
 Posterior acoustic shadowing
 Slice thickness artifact (Caused by the increased width of the
beam beyond the focal zone of the transducer) I call it a “crosseyed beam” artifact in that several different structures are
detected by the beam simultaneously.
 Cystic structure
 Solid structure
 Complex structure
Patient care
 Electrical Safety
 Always use proper grounded




electrical devices with threeprong plugs.
Avoid the use of extension
cords.
Do not use any device with
frayed cords.
Inspect systems routinely.
During an ECG, patient
should not be grounded, but
chassis of ECG machine
should be grounded.
Patient relations, confidentiality & Assessment
 In 1996, Congress enacted the
Health Insurance Portability and
Accountability Act, or HIPAA.
 The primary purpose was
continuity of health insurance
coverage if you change jobs, but
is also provided for standards for
health information transactions
and confidentiality and security
of
patient
data.
This
confidentiality portion will most
affect the day-to-day workflow
among
health
care
professionals.
Privacy
 Privacy
is somewhat different than
confidentiality. It refers to individuals’
right to keep some information to
themselves and to have it used only with
their approval. Under HIPAA, physicians
must use and disclose only the minimum
necessary amount of patient information
needed fro the purpose in question. The
institution may use and disclose patient
information for treatment, payment, and
health care operations without patient
authorization. Most other uses and
disclosures of patient information require
such an authorization.
 Liability
 Holds each individual responsible for
their actions.
 Negligence
 Doing something that a reasonable
person will not do or Not doing
something that a reasonable person
would do.
 Informed consent
 Protects doctor from claims of
unauthorized procedure. In order to be
legally binding, patient must be
capable of giving consent (before given
morphine, etc.) For invasive
procedures, informed consent should
be given to operating physician or
cardiologist.
 Interpretation of exams
 Sonographers cannot provide
interpretation of exam to
patient. Interpretation must
come from physician.
 Malpractice
 Claims can be avoided by
effective communication
between patients and medical
personnel.
 Denial
 The refusal to acknowledge the
existence or severity of
unpleasant external realities or
internal thoughts and feelings.
 Initial assessment
 Including vitals, are used to
establish a baseline to
compare future results.
 Wheelchair
 Moving a patient in or out-
brakes engaged, footrests
retracted.
Foley Catheter
 An indwelling Foley catheter is a flexible
plastic tube that is inserted through the
urethra into the bladder, to drain urine.
 To keep the catheter for slipping out, it as
a balloon on the end that is inflated with
sterile water or saline once the end is
inside the bladder.
 Keep the urinary drainage bag below the
level of he bladder to keep the fluid
flowing from the bladder into the
collection bag. If the bag is elevated above
the bladder, urine will collect in the
bladder.
Sterilization
 Sterilization is the elimination of all
transmissible agents (such as bacteria and
viruses) from a surface or a piece of
equipment. This is different from
disinfection, where only organisms that
can cause disease are removed by a
disinfectant.
 In general, any instrument that enters an
already sterile part of the body (such as
the blood, or beneath the skin, should be
sterilized. This includes equipment like
scalpels, hypodermic needles, and
artificial pacemakers.
 Pathogens
or
infectious
agents are biological agents
that causes disease or illness
to its host. Pathogens disrupt
the normal physiology or an
animal or plant. The term
pathogen is derived from the
Greek “Birth of Pain”.
 The human body has many
natural defenses against
some of the more common
pathogens in the form of the
human immune system and
by some helpful bacterial
present in the human body’s
normal flora.
 However, if the immune system or good
bacteria is damaged, pathogenic bacteria
that were being controlled can multiply
and cause harm to the host. Such cases
are called opportunistic infections.
 Flora- Mucus membranes, such as the
intestinal lining, are constantly in contact
with environmental organisms and
become readily colonized by various
microbial species, called flora.
 Pathogens are responsible fro massive
amounts of casualties and have harmful
effects on affected groups. (AIDS)
Methods of Sterilization
Preferred principle for sterilization is through
heat and pressure. There are also chemical
methods of sterilization.
1. Autoclaves
A widely-used method for heat sterilization
is the autoclave. Autoclaves use steam
heated to 121 degrees C (250 F)and pressure
at 103 kPa (15 psi) above atmospheric, for 15
minutes. The steam and pressure transfer
heat into organisms to kill them. Useful
parameters – time and temperature.
2. Chemical Sterilization
Chemicals are also used for
sterilization. Although heating
provides the most effective way
to destroy transmissible agents,
it is not always appropriate,
because it destroys objects such
as fiber optics, electronics, and
plastics.
Ethylene oxide (EO) gas is
commonly used to sterilize
objects that cannot survive
temperatures greater than 60
degrees C, such as plastics,
optics, and electrics.
 Sepsis
 Means to soil or dirty. “A”
means without.
 Aseptic means without
microorganisms.
Aseptic
technique
refers
to
practices that reduce post
procedure infection
in
patients by decreasing the
likelihood
that
microorganisms will enter
the body during clinical
procedures.
Sterile Fields
 A sterile field is an area created
by placing sterile towels or
surgical drapes around the
procedure site and on the stand
that holds sterile instruments
used during the procedure.
 The doctor’s sterile area is the
only area that should come in
contact with the sterile field.
Only sterile objects and
personnel may be allowed in the
sterile field. The sterile area
should be draped starting from
the area closest to the person
and extending outward.

While a sterile field is created around a
procedure site, items below the level of the
draped client are outside the field and are not
sterile. A properly gowned and gloved person’s
sterile area extends from the chest to the level
of the sterile field. Sleeves are sterile from 5
cm ( 2 inches) above the elbow to the cuff.

Once a sterile object comes in contact with a
non-sterile object or person or with dust or
other airborne particles, the object is no longer
sterile. If even one non-sterile object or person
enters the sterile field, the field is no longer
sterile. For example, sterile objects become
contaminated if you touch the object with your
bare hand, if the object comes into contact
with dust or other airborne particles, or if the
object is held below the level of the sterile
field.

The spike of an IV set is sterile and must not
come in contact with non-sterile objects.
To maintain the Sterile Field
1. Do not place sterile items near
2.
3.
4.
5.
open window or doors
Place only sterile items within
the sterile field
Do not contaminate sterile
items when opening,
dispensing, or transferring them
Consider items located below
the level of the drape to be
unsterile.
Do not allow sterile personnel
to reach across unsterile areas
or to touch unsterile items.
6. Do not allow unsterile personnel to reach
across the sterile field or to touch unsterile
items.
7. Recognize and maintain the provider’s
sterile area.
8. Recognize that the edges of a package
containing a sterile item are considered
unsterile.
9. Recognize that a sterile or high-level
disinfected (HLD) barrier that has been
penetrated (wet, cut, or torn) is considered
contaminated
10. Be conscious of where your body is at all
times, and move within or around the sterile
or HLD field in a way that maintains sterility or
HLD status.
Radiopaque objects: block radiation and
appear white on a x-ray film.
Bodily Fluid Spills
 Care must be taken with
blood, vaginal secretions,
saliva in dental procedures or
any body fluid that is visibly
contaminated with blood. In
addition, care must be taken
in situations where it is
difficult or impossible to
differentiate between body
fluids.
 Universal
precautions
in
emergency situations suggest
that all body fluids are
potentially infected material
(PIM).
Infectious fluids can enter our
bodies through:

Absorption through mucus
covering the body openings

Through an open, bleeding wound

Through damaged areas of the skin, caused by
other severe skin diseases.

Mucus membranes are much thinner than
normal skin. Microscopic cuts in the
membranes can allow germs to cross the
membrane and enter the blood stream. Also,
fluids can be absorbed through these
membranes even without any cuts or breaks.

Normal skin is much thicker than mucous
membranes and provides a good barrier to
blood diseases. Infectious fluids cannot be
absorbed through skin that is intact.
membranes
Have these materials on hand for cleaning up spills:

A durable container to store the clean up supplies

Several biohazard labeled bags

Disinfectant-freshly prepared 10% solution of
household breach ( 1 part bleach and 9 parts water,
or add ½ cup bleach to 1 quart water) or other
commercial chlorine or iodine based disinfectant

Inert absorbing material (Kitty litter)

A small dust pan and hand brush

Personal protective equipment, including several
pairs of latex gloves, goggles, face masks, coveralls,
and paper boots.

A roll of paper towels

Antiseptic wipes
Cleaning a Blood Spill
1.
If blood has spilled onto you, it should be
thoroughly washed off as soon as
possible. If the material has spilled on
your clothing and soaked through so that
that is skin contact, the cloths must be
removed. Following removal, wash those
areas where exposure is evident, even to
the point of taking a shower. If blood or
PIM has come into contact with any of the
mucous membranes (eyes, nose, lips)
they need to be thoroughly rinsed. If
there is contact with open wounds or
cracks (chapped skin) in the skin, there is
a risk of exposure. Immediately and
thoroughly wash your hands with water
and soap or an antiseptic cleaner if
contaminated with a body fluid.
2. When clean up involves blood or a flat surface, you
should first delineate and mark the spill area so that
others do not inadvertently enter the area until clean up is
complete.
3. Soak the area for at least 20 minutes with a disinfectant
(freshly prepared 10% bleach solution). You can be liberal
with disinfectant but don’t apply so heavily that it begins
to run.
4. Allow at least 20 minutes with a disinfectant to
complete the decontamination. You can use the small
hand broom and dustpan to clean up the spill.
5. Deposit all clean up material in bio-waste disposal bag
and close tightly. The bag should be secured in a
biohazard BURN BOX. Carefully remove gloves, coveralls,
and boots (if used) and discard in a bio-waste bag. If used,
the facemask should also be disposed. Goggles can be
disinfected, rinsed, and reused. The dustpan and broom
can be disinfected and reused.
6. Record and report the incident to your supervisor.