Deck 6: Electromagnetic Modalities: Laser, Diathermy, and Pulsed Electromagnetic Fields

Question 1

The physiological effect of low-level laser therapy (LLLT) can be attributed to which of the following?

A) Thermal effects on treated tissues
B) Activation of photosensitive neurons in the dermis
C) Photochemical activation of enzymes that catalyze processing of molecular substrates
D) Vasodilation of capillary beds

Answer 1

C

Question 2

At thermal intensities, therapeutic effects of diathermy include

A) Promotion of bony healing after total joint arthroplasty
B) Increased collagen elasticity in soft-tissue contractures
C) Decreased amount of adipose tissue in obese individuals
D) Decreased back pain typical during the third trimester of pregnancy

Answer 2

B

Question 3

Which of the following is true about electromagnetic energy?

A) Has matter that is equal in mass to its frequency
B) Transfers heat via conduction
C) Travels through space without a transport medium
D) Requires contact with the body or another conducting pathway

Answer 3

C

Question 4

Which of the following answers includes only contraindications and precautions for diathermy?

A) Metal implants, pacemaker, muscle spasm
B) Over cancerous tissue, hemophilia, over testes
C) Pregnancy, pelvic inflammatory disease, non-acute inflammation
D) Infection, chronic obstructive pulmonary disease (COPD), mechanical joint pain

Question 5

Which is true regarding the physical properties of laser light?

A) Laser light is generated by spontaneous emission.
B) Light from a laser scatters like an overhead lamp.
C) The color of laser light depends on the medium through which it travels.
D) Laser light is monochromatic and coherent.

Question 6

Which of the following should not be treated with LLLT?

A) Chronic epicondylitis
B) Herpes simplex wounds
C) Carpal tunnel syndrome
D) Open growth plates of bones

Question 7

Which of the following best describes the results of research studies on the effects of diathermy on pain?

A) Reduction of pain occurred in studies using thermal and nonthermal diathermy.
B) Reduction of pain occurred only in studies using thermal diathermy.
C) Studies are inconclusive.
D) Insignificant changes in pain levels occurred following diathermy.

Question 8

Your patient has lumbar spine pain. She has heard about LLLT and asks you if it will help relieve her pain. The most appropriate response to her question would be

A) Many research studies have found LLLT to effectively relieve low back pain.
B) Recent evidence has found that LLLT combined with massage will decrease low back pain.
C) A randomized controlled trial study found LLLT to be ineffective for lumbar spine pain.
D) Daily treatments using LLLT to trigger points in the low back will likely decrease your pain.

Question 9

Which is true regarding pulsed shortwave diathermy (PSWD)?

A) Mild heat sensation occurs when the mean power of PSWD exceeds 38 watts.
B) The power output monitor on the device is more accurate than patient perception of tissue heating.
C) The amount of heating of tissues is inversely related to tissue resistance.
D) PSWD is capable of performing vigorous heating of soft tissue.

Question 10

What is the primary difference between lasers and light-emitting diodes (LEDs)?

A) Laser light is monochromatic and LED light is polychromatic.
B) Light emitted by LEDs has limited coherence and directionality.
C) Laser light can produce heat in biological tissues and LEDs cannot produce heat.
D) LED light is produced by radio waves emitted by supra-luminous diodes.

Question 11

Which of the following electromagnetic waves travel through space at the speed of light?

A) Ultraviolet waves
B) Radio waves
C) Infrared waves
D) All electromagnetic waves travel at the speed of light.

Question 12

Which of the following best describes the results of research studies on the effects of diathermy on tissue flexibility?

A) There was insignificant changes in flexibility of soft tissues.
B) It must be combined with frequent, brief-duration stretching to be effective.
C) Studies are inconclusive.
D) There was increased flexibility with or without stretching of tissues.

Question 13

You have decided to use LLLT for treatment of lateral epicondylitis. Which of the following lasers is the best choice for absorption of light energy in the tissues attached to the lateral epicondyle at a depth of 2 to 3 millimeters from the skin?

A) HeNe red laser at 632 nm
B) GaAs infrared laser at 830 nm
C) GaAl laser at 930 nm
D) Nd-YAG pulsed laser at 1,200 nm

Question 14

Which of the following modalities would be the best choice to heat the posterior hip joint capsule prior to joint mobilization?

A) Pulsed electromagnetic fields (PEMFs)
B) Continuous shortwave diathermy (CSWD)
C) Low-level laser therapy (LLLT)
D) 3 MHz continuous ultrasound

Question 15

Why must all external metallic objects be removed in the vicinity of diathermy treatments?

A) Metals can interfere with the flow of electromagnetic waves.
B) Metallic objects will block the transmission of electromagnetic waves.
C) Metals will heat faster than tissues, which may cause burns.
D) Metallic objects will prevent proper positioning of the capacitive plates or inductive drums.

Question 16

Your patient has a medical history of impaired sensation in her lower extremities. If you chose laser for treatment of a condition in her lower extremities, which of the following laser therapy treatments must be performed with caution?

A) High-intensity lasers and superluminescent light-emitting diode (SLED) arrays
B) Infrared laser at a dosage of 2 J/point
C) HeNe laser at a dosage of 8 J/point
D) Nd-YAG pulsed laser at 12 J/point

Question 17

Which of the following correctly describes the inductive method of diathermy?

A) Creation of electromagnetic eddy currents in conductive tissues
B) Preferential heating of tissues with high electrical resistance
C) Induction of capacitive currents around the electrical field
D) Body part between electrodes becomes part of the electrical field

Question 18

Dosage for LLLT should be documented as which of the following?

A) Watts per square centimeter or point
B) Joules per square centimeter or point
C) Photons per centimeter or point
D) Milliamps per centimeter or point

Question 19

Your patient has a chronic flexion contracture of the left knee. Which of the following dosages would be most appropriate if you chose to apply diathermy prior to stretching the knee?

A) Nonthermal
B) Mild heat sensation
C) Moderate heat sensation
D) Vigorous heating

Question 20

Thermal effects of diathermy are believed to be caused by which of the following?

A) Accelerated motion of ions, dipoles, and/or electron clouds
B) Depolarization of peripheral neurons, resulting in vasodilation
C) Magnetic optimization of resonance frequencies
D) Attenuation of energy beam as it travels through tissue interfaces