Week 3- Ultrasound and Laser, Thermo/Cold Therapy and Short Wave Diathermy Flashcards
ULTRASOUND AND LASER
ULTRASOUND AND LASER
What is ultrasound?
- Therapeutic modality where high-frequency sound waves are transmitted through a wand or probe into the body.
- Sound waves lead to vibrations of the molecules in the body.
Sound waves can be either _______,__________, or ____________.
- reflected
- refracted
- absorbed
What are the 2 main equipment components for ultrasound?
- generator
- applicator
The generator is the “___ ____” of the US device that generates the high-frequency alternating current that is transmitted through the applicator.
“big box”
The applicator is composed of __________ and ___________ crystal in the soundhead.
- soundhead
- piezoelectric
What does the piezoelectric crystal do?
Expansion and compression of the crystal produces the sound waves.
What does the soundhead do?
Acoustic energy from the crystal is conducted to the sound head then through a conductive gel into the skin.
Is the crystal perfectly uniform? What does this lead to?
- No
- Leads to nonuniformity of the intensity of the beam (beam nonuniformity ratio (BNR))
What is spatial peak intensity?
Power of beam at highest point of effective radiating area.
What is spatial average intensity?
total power (watts) across the transducer head (cm²) usually what is recorded for intensity during treatment. (W/cm²)
What is beam non-uniformity ratio?
Ratio of spatial peak intensity and spatial average intensity.
What does a beam non-uniformity ratio of 1:1 mean?
Means the beam is close to uniform throughout.
- What is absorption?
- What is refraction?
- What is Reflection?
Absorption
-When the kinetic energy of movement is absorbed by tissue and transformed into thermal energy.
Refraction
-Ultrasound signal is deflected from a straight path and the angle of deflection is away from the transducer.
Reflection
-Ultrasound waves are deflected towards the transducer.
What are standing waves? What reduces them?
- Standing waves are when reflected waves interact with waves going in and creates more energy.
- This is reduced by keeping the sound head moving.
Intensity is the power of the ultrasonic energy and is expressed as __/____. There are no difinitive guidelines for intensity but continuous (thermal) is typically __-__ W/cm².
- W/cm²
- 0.5-3 W/cm²
What is attenuation in regards to US?
-Reduction of acoustical energy as it passes through soft tissue.
- Do absorption, reflection, and refraction affect attenuation?
- Absorption is highest in tissues of ________ density.
- Reflection of acoustic waves can create ________ waves and thus an increased intensity.
- Yes
- greater
- standing waves
Rate these in order from low attenuation to high attenuation:
- Muscle
- Skin/Tendon
- Bone
- Cartilage
- Blood/Fluids
LOW 1.) Blood/Fluids (3%) 2.) Muscle (24%) 3.) Skin (39%)/Tendon (59%) 4.) Cartilage (68%) 5.) Bone (96%) HIGH
- Frequency is the _______ of waves per second delivered.
- What are the 2 most common frequencies and how deep do they penetrate?
-number
- 3MHz (UP TO 2.5cm DEEP)
- 1MHz (UP TO 5cm DEEP)
3MHz leads to greater heat production in _________ layers due to increase in scatter (________) of sound waves in superficial tissue.
- superficial
- attenuation
1MHz heats _______ layers due to less scatter in superficial tissue, thus more energy able to penetrate deeper.
deep
What is duty cycle (mode) of US?
Fraction of time the US energy is on over one pulsed period (time on + time off)
What are the types of duty cycles (modes)?
- Continuous (thermal)- US is applied at a constant energy level; duty cycle 100%
- Pulsed (nonthermal)- duty cycle range usually 5%-50%.
What are the 3 most common duty cycle mode %’s seen?
20%, 50%, and 100%
Indications for Use of US:
- Modulate _____
- Increase ____________ extensibility
- Reduce muscle ______
- Increase tissue _________
- Increase blood ____
- Facilitate ________
- pain
- connective tissue (CT)
- spasm
- temperature
- flow
- healing
Contraindications for US:
- Impaired ________
- Impaired _________ function
- Absent _________
- Cancer
- Joint cement
- Directly over ________ components
- Over ______ areas (brain, eyes, heart, ear, reproductive organs)
- Pregnancy
- circulation
- cognitive
- sensation
- plastic
- vital
Precautions for US:
- Acute __________
- Open ________ Plates
- Healing ________
- Breast Implants
- inflammation
- epiphyseal
- fracture
What is the intention of thermal (continuous) US?
Increasing tissue temperature through friction (aka vibration) between molecules (1-5cm depth dependent on frequency)
Proposed impacts of thermal US:
- Increased pain _________
- Increased collagen extensibility
- Alteration of nerve conduction velocity
- Increased enzymatic activity
- Increased tissue _________
- threshold
- perfusion
Excessively high temperatures of thermal US may produce sudden strong ache caused by overheating of periosteal tissue (periosteal pain); if occurs reduce __________ or increase treatment ___________.
- intensity
- surface area
Insufficient coupling agent may produce discomfort due to a “hot spot” (periosteal pain) which is uneven distribution of the acoustic energy through the sound head; if occurs add more _________ and ensure ___________ movement.
- coupling
- soundhead
What are the 2 theories for the intention of non-thermal (pulsed) US?
Cavitation
-Alternating compression and expansion of small gas bubbles in tissue fluids due to the mechanical pressure waves of the acoustic waves.
Acoustic Streaming
-Forward movement of fluid and ions along boundaries of cell membranes.
What are the 2 types of cavitation?
Stable Cavitation
-Gas bubbles resonate without tissue damage; may be responsible for diffusional changes in cell membranes.
Unstable Cavitation
-Severe collapse of gas bubbles during compression phase of pulsed US which can results in local tissue damage due to high temperatures.
Application Techniques:
- ) Explain procedure and explain they must tell operator if discomfort or painful.
- ) Select soundhead; should be about __ treatment area; if area to be treated is greater than 2 times the size of the soundhead perform two separate treatments
- ) Cover area or sound head with generous amount of gel medium
- ) Turn on unit and set timer
- ) Set _________ and _______
- ) Place sound head firmly on patient and begin motion in overlapping circles or longitudinal strokes; each motion should cover ½ of previous circle or stroke
- ) Adjust intensity as desired
- ) Begin timer countdown
- ) Treatment ends with timer sounding and shut off unit
- ) Remove soundhead and clean gel from patient
- ½
- frequency and mode
- When is the Immersion Technique US indicated?
- Imemrsion technique is useful for ________ surfaces, _______ or broken integument.
- When criteria for direct contact can not be safely met.
- irregular, sensitive
How is the immersion technique performed?
-Patient area placed in water in plastic containter.
-Immersion of US head in basin and hover 1cm from treatment area.
-Perform same rhythmic movement over area as you would with direct contact.
Remove and dry patient and equipment.
What are some things you would document when performing US?
- Treatment area
- Patient position
- Parameters (frequency, mode, duty cycle, intensity, treatment time, transducer size)
- Outcome measures (pain, tenderness on palpation, tenderness with resisted motion, ROM)
What is phonophoresis?
- Using US sound waves to attempt to deliver medications through skin.
- Very limited/weak evidence of efficacy
What does Laser stand for?
Light Amplification by Stimulated Emission of Radiation
- The amount of laser light energy absorbed by biological tissues depends on the ________ of light.
- What is the power output measured in?
- wavelength
- W or mW
Low-Level Lasers = peak power equal or less than ____mW
High-Intensity Lasers = peak power greater than _____mW
- 500mW
- 500mW
What are the main uses of laser treatment?
- tissue repair
- increased vasodilation
- reducing inflammation
- reducing pain
Contraindications for Laser:
- Direct ____ exposure
- Pregnancy
- Malignancy
- Following ______ injury where hemorrhage is possible or suspected
- Open _______ plates
- Over the ________ or other endocrine gland
- eye
- acute
- growth
- thyroid
How to explain laser treatment?
- Energy going in, cells absorb allowing to work longer and harder to speed up healing process.
- Safe
- Minimal amount of time
THERMO AND CRYO THERAPY
THERMO AND CRYO THERAPY
What are the 3 ways heat/cold are transmitted?
Conduction
-Transfer from a one object to a another by direct physical contact; effective 1-3cm depth
Convection
-Transfer by movement of air or fluid moving past a body part; affective 1-3cm depth
Radiation
-Transfer from one object to another object by transmission of electromagnetic energy
What are the goals of heat (thermo) therapy?
- Decrease pain and stiffness
- Alleviate muscle spasms
- Increase ROM and tissue extensibility
- Improve tissue healing by increasing blood flow
What are the INCREASED physiological responses to local heat?
- blood flow
- capillary permeability
- elasticity of nonelastic tissue
- metabolism
- vasodilation
- edema
What are the DECREASED physiological responses to local heat?
- joint stiffness
- muscle spasm
- pain
Rate the structures in order from which gets the most heat to the least heat from localized heat:
- Muscles and joints
- Skin
- Subcutaneous tissue
MOST
1.) Skin (greatest temp change)
2.) Subcutaneous tissue (less rapid temp rise)
3.) Muscles and joints (depends on size and depth)
LEAST
Contraindications for Localized Heat:
- Acute __________ conditions
- Absent _______
- DVT
- Impaired _______ function
- Malignant tumor in area of application
- Tendency toward ___________
- inflammatory
- sensation
- cognitive
- hemmorhage
Precautions for Localized Heat:
- Cardiac insufficiency
- Decreased ________
- Decreased mentation
- Impaired _________
- Impaired thermal regulation
- _______ in treatment area
- Open wounds
- Demyelinated nerves
- sensation
- circulation
- metal
What are 3 methods used for localized heat?
- Moist Hot Pack
- Paraffin Bath
- Whirlpool
Moist Hot Packs method of transmission is ________. They are stored in a hydrocollator (165-170 degrees) and MUST BE WRAPPED IN - layers (hydrocollator covers = 2 layers
- conduction
- 6-8 layers
What are the precautions of moist hot packs?
- weight of MHP
- position of patient
- if patient falls asleep
Paraffin Bath method of transmission is _________. It is useful in treatment of _______ joints.
- conduction
- small joints
- What are 2 methods of use for paraffin bath?
- How long is a paraffin bath usually?
- ) Glove- dip 5-6 times then wrap with plastic or towel
- ) Immersion- suspend in wax
-15-20 minutes
What are the contraindications for paraffin bath?
- allergic rash
- open wounds
- recent scars
- skin infections
Whirlpool method of transmission is ________. This involves partial or total immersion of body part in water which is agitated with air against or around body part. The treatment time is ___ minutes.
- convection
- 20 minutes
What are the precautions for whirlpool?
- decreased sensation
- decreased cognition
- recent skin graft
What is the contraindication for whirlpool?
open wound
What are the goals of cold (cryo) therapy?
- decrease pain
- reduce inflammation or swelling
- alleviate muscle spasm
- reduce spasticity
- management in MS
- cryostretch
Cryotherapy method of transmission is primarily ________ and _____________.
- conduction
- evaporation
What are the INCREASED physiological responses to local cold?
- increased muscle strength (only 1-5 minutes)
- increases joint stiffness
What are the DECREASED physiological responses to local cold?
- decrease muscle spasm
- decreases nerve conduction velocity
- decreases pain/increases pain threshold
- decreases metabolism
How is cold treatment used in acute trauma?
- Vasoconstriction and decreases fluid filtration into interstitial tissue
- Decreased metabolism and vasoactive agents = decreased inflammation and edema
- Increases pain threshold
Rate the structures in order from which gets the most affected to the least affected from cryotherapy:
- Muscles and joints
- Skin
- Subcutaneous tissue
MOST
1.) Skin (greatest temp change)
2.) Subcutaneous tissue (less rapid temp fall)
3.) Muscles and joints (requires long cold exposure)
LEAST
Skin blanching can occur from small area cold application, what is this?
Vasoconstriction of skin capillaries; hyperemia around edge of contact area in normal tissue due to a decreased rate of oxyhemoglobin dissociation.
Cold-induced ________ can occur following prolonged cold exposure occuring most often in the hands, feet, and face.
vasodilation
Can there be a histamine (allergic) reaction to cold application? If so, what can occur?
-Yes
- Facial flush, puffiness eyelids, respiratory problems, in severe cases anaphylaxis with syncope
- Cold urticarial: erythema of the skin with wheal formation associated with severe itching due to histamine reaction
Contraindications for Cold Therapy:
- Cold _____sensitivity (_________)
- Cold intolerance
- Cryoglobulinemia
- ________ vascular disease
- Severe impaired temperature sensation
- _________ diseases
- Paroxysmal cold hemoglobinuria
- Over regenerating peripheral nerves
- hypersensitivity (urticarial)
- peripheral
- Raynaud’s
Precautions for Cold Therapy:
- ______tension
- Impaired temperature sensation
- Open wound
- Over _________ nerve
- Cognitive changes
- hypertension
- superficial
- What is the duration of cryotherapy?
- What are the post treatment precautions?
- 10-30 minutes (longer if casts/bandages), ice massage can be shorter
- avoid excess stresses to area 1-2 hours post-treatment
What are 3 methods used for cryotherapy?
- Ice Massage
- Vapo-coolant
- Contrast Bath
Ice massage method of transmission is ________. Ice is applied to an area no larger than x inches in slow overlapping circles or longitudinal strokes.
- conduction
- 4x6
Ice massage is continued until anasthesia is achived which is generally within - minutes.
-5-10 minutes
What is the patient experience with ice massage?
- cold
- burning
- aching
- numbness
Vapo-coolant method of transmission is ________. The goal is to reduce muscle ______ and/or desensitize trigger points.
- evaporation
- spasm
For vapo-coolant, we want to hold the can __-__ in from the treatment area at a ___ degree angle and sweep spray over the treatment area.
- 18-24 inches
- 30 degree
With vapo-coolant we allow the liquid to completely evaporate before applying next sweep, DO NOT _____ skin.
frost
After application of vapo-coolant, we _________ stretch then apply moist heat. After application of moist heat we want the patient to perform ______ exercise.
- passively
- active
Contrast Bath method of transmission is __________. This involves the alternating immersion of body part between warm and cold water. The goal is to produce vascular exercise through active ____________ and ___________ of blood vessels; may help with pain modulation.
- conduction
- vasodilation and vasoconstriction
What are the indications for the use of a contrast bath?
- any condition requiring peripheral circulation stimulation
- sprains
- strains
How is the contrast bath treatment performed?
- Place part in cold water (50-64 degrees) for 1 minute, then transfer to warm water (100-111 degrees) for 3-4 minutes then transfer back.
- Continue 5-6 times of 4:1 (warm:cold) usually ending in warm, but may end in cold if goal is edema reduction
- treatment time is 25-30 minutes
Is short wave diathermy for heating or cooling?
- Heating
- Electromagnetic energy produces deep heat within tissues
What are the 2 types of short wave diathermy?
Continuous (thermal)
-Increases temp in deeper structures
Pulsed (nonthermal)
-Allows dissipation of heat during the off cycle and can result in other physiological/therapeutic effects
What are the 2 methods of short wave diathermy?
- Electrical field (Capacitive) method
- Magnetic field (Inductive) method
What are the physiological effects of Continuous (Thermal) Short Wave Diathermy?
- Increased temperature to deep and superficial tissues
- Increased soft tissue extensibility
- Increased nerve conduction
- Vasodilation
What are the indications and goals of Continuous (Thermal) Short Wave Diathermy?
- Increased joint ROM
- Pain management
- Increased tissue healing
What are the physiological effects of Pulsed (Nonthermal) Short Wave Diathermy?
- Increased microvascular perfusion
- Increased local tissue oxygenation
- Increased cell growth and phagocytosis
- May help healing of wounds and diabetic ulcers
What are the indications and goals of Pulsed (Nonthermal) Short Wave Diathermy?
- Pain control
- Decrease edema
- Resolution of acute and chronic infections
- Wound control and soft tissue healing
Contraindications to Diathermy:
- Pregnancy- Patient or _________
- Implanted neural or cardiac _________
- Specific to continuous (thermal): open epiphyses, metal implants and jewelry, malignancy, near the testes or eyes
- Specific to pulsed (nonthermal): over diseased internal organs, over metal loops that secure plates or rods
- therapist
- stimulators
Precautions to Diathermy:
- Use of equipment near _________ or magnetic equipment
- Patients or nearby personal with _______ bearing intrauterine devices
- electronics
- metal
What is the Capacitive Method of Short Wave Diathermy?
- Body part being treated is placed between 2 electrically charged plates.
- Patient becomes part of the circuit
- Charged particles oscillate and tissue temp increases
- Can cause electrical burn if patient’s skin touches electrode/plate
- Heat produced is more superficial under each plate
The Capacitive Method can be divided into _____planer or ____planar. What is the difference?
Contraplanar
-Plates positioned on each side of the body part.
Coplanar
-Parallel to one another on the same body surface.
What is the Inductive Method of Short Wave Diathermy?
- Alternating current in a coil produces a magnetic field which creates an oscillating magnetic field (“eddy” current); vibration causes temperature to rise in tissue
- Strength of magnetic field and distance of the applicators and conductivity of the tissue determine degree of heat generation
- Collagen, fat, and bone = _____ conductivity
- Muscle, synovial tissue = _____ conductivity
- low
- high
Summary:
- What are the 2 types of Diathermy? (Know the Physiological Effects, Contraindications, and Precautions)
- What method of diathermy involves use of an electrical field?
- What method of diathermy involves use of a magnetic field?
- Continuous (Thermal) and Pulsed (Nonthermal)
- Capacitive Method
- Inductive Method
