A detailed lecture about sleep physiology and an overview of some sleep disorders

1. SLEEP
DISORDERS
Dr.Jaidaa Mekky
A.Prof of Neuropsychiatry
Faculty of Medicine- Alexandria University
Member of the AAN. AASM , ESRS

2. SLEEP
 A revesible state of unresponsivnes to the enviroment
 Brain is more responsive to internal than external stimuli
 Less responsive to visual, auditory, and other environmental stimuli
during the transition from wake to sleep.

3. Milestones
 1837 – Dickens – describes overweight/hypersomnolent
boy in the Posthumous Papers of the Pickwick Club (term
“pickwickian” used by Osler)
 1928 – Berger – Human EEG alpha waves
1937 – Loomis – EEG Sleep stages
1953 – Aserinsky & Kleitman – REM sleep
 1970s – Polysomnography
 1972 – Guilleminault – coins term OSA
 1990 – International Classification of Sleep Disorders

4. 2000 B.CEgypt
 The Egyptians wrote these dreams on papyrus with dreams symbols.
 Egyptians were among the early civilizations to attempt interpretation of their dreams.
Egypt was where the process of "dream incubation" began. When a person was having
troubles in their life and wanted help from their god, they would sleep in a temple, when
they would wake the next morning a priest, which was then called a 'Master of the Secret
Things', would be consulted for the interpretations of that night's dreams.

6. Famous Dreams
‫اﺑﺮاھﯿﻢ‬ ‫ﺳﯿﺪﻧﺎ‬
ْ‫ذ‬َ‫أ‬ ‫ﻲ‬ِّ‫ﻧ‬َ‫أ‬ ِ‫م‬‫ﺎ‬َ‫ﻨ‬َ‫ﻤ‬ْ‫ﻟ‬‫ا‬ ‫ﻲ‬ِ‫ﻓ‬ ‫ى‬َ‫ر‬َ‫أ‬ ‫ﻲ‬ِّ‫ﻧ‬ِ‫إ‬ ‫ﱠ‬‫ﻲ‬َ‫ﻨ‬ُ‫ﺑ‬ ‫ﺎ‬َ‫ﻳ‬ َ‫ل‬‫ﺎ‬َ‫ﻗ‬ َ‫ﻲ‬ْ‫ﻌ‬ ‫ﱠ‬‫اﻟﺴ‬ ُ‫ﻪ‬َ‫ﻌ‬َ‫ﻣ‬ َ‫ﻎ‬َ‫ﻠ‬َ‫ﺑ‬ ‫ﺎ‬‫ﱠ‬‫ﻤ‬َ‫ﻠ‬َ‫ﻓ‬‫ﺎ‬َ‫ﻳ‬ َ‫ل‬‫ﺎ‬َ‫ﻗ‬ ‫ى‬َ‫ﺮ‬َ‫ﺗ‬ ‫َا‬‫ذ‬‫ﺎ‬َ‫ﻣ‬ ْ‫ُﺮ‬‫ﻈ‬‫ﺎﻧ‬َ‫ﻓ‬ َ‫ﻚ‬ُ‫ﺤ‬َ‫ﺑ‬‫ﺎ‬َ‫ﻣ‬ ْ‫ﻞ‬َ‫ﻌ‬ْ‫ﻓ‬‫ا‬ ِ‫ﺖ‬َ‫ﺑ‬َ‫أ‬ُ‫ﺮ‬َ‫ﻣ‬ْ‫ﺆ‬ُ‫ﺗ‬
َ‫ﻳﻦ‬ِ‫ﺮ‬ِ‫ﺑ‬‫ﺎ‬‫ﱠ‬‫ﺼ‬‫اﻟ‬ َ‫ﻦ‬ِ‫ﻣ‬ ُ‫ﻪ‬‫ﱠ‬‫ﻠ‬‫اﻟ‬ َ‫ء‬‫ﺎ‬ َ‫ﺷ‬ ْ‫ن‬ِ‫إ‬ ‫ﻲ‬ِ‫ﻧ‬ُ‫ﺪ‬ِ‫ﺠ‬َ‫ﺘ‬ َ‫ﺳ‬) .‫اﻟﺼﺎﻓﺎت‬:۱۰۲(
‫ﻳﻮﺳﻒ‬ ‫ﺳﯿﺪﻧﺎ‬ ‫روئ‬
)‫ﺳﺎﺟﺪﻳﻦ‬ ‫ﻟﻲ‬ ‫رأﻳﺘﮭﻢ‬ ‫واﻟﻘﻤﺮ‬ ‫واﻟﺸﻤﺲ‬ ‫ﻛﻮﻛﺒﺎ‬ ‫ﻋﺸﺮ‬ ‫أﺣﺪ‬ ‫رأﻳﺖ‬ ‫إﻧﻲ‬ ‫أﺑﺖ‬ ‫ﻳﺎ‬ ‫ﻷﺑﯿﻪ‬ ‫ﻳﻮﺳﻒ‬ ‫ﻗﺎل‬ ‫إذ‬(
‫ﺳﯿﺮﻳﻦ‬ ‫ﻻﺑﻦ‬ ‫اﻻﺣﻼم‬ ‫ﺗﻔﺴﯿﺮ‬

7. Mechanism of
normal sleep and
wakefulness
Homeostasis
process
REM sleep NonREM sleep
Circadian process
- Melatonin
- Body
temperature
- Cortisol.

8. Homeostatic process
 Sleep homeostasis can be modeled by assuming there is a
quantitative need for sleep that builds while a person is
awake and declines during sleep.
 The homeostatic pressure to sleep depends on how long
you are awake and how active you are while awake.

9. Circadian process
 It helps keep the homeostatic process in line.
 It helps us sleep through the night and not drop off during the day.
Physiologists who use this model often call the homeostatic process "Process S" and the
circadian one "Process C."

12. HOW MUCH
SLEEP DO
WE NEED?

13. Functions of sleep
 Energy conservation
Energy is conserved during sleep: muscular tension, heart rate, blood pressure,
temperature and rate of respiration are reduced.
 Memory consolidation& learning
sleep, especially REM, may actively contribute through processes that consolidate
the learned material.
 Body restoration & Immune function

14. Theories
of
functions
of sleep
Restoration
and Recovery
Energy
conservation
Ontogenesis
(Brain
development)
Memory
processing
and
consolidation
Ecological
Hypotheses Of
Foraging and
Predator
Avoidance
10% decrease
MR, heat is
dissipated thr
peripheral VD,
which leads to a
1-2°C reduction
in body
temperature
Energy restores,
wound healing,
immune system,
GH in adult men,
Activating the
synapses,
Nerve cell dendrites'
sending of
information to the
cell body to be
organized into new
neuronal
connections.
Demands no
external information
Inactivity
during sleep
may minimize
exposure to
predators

15. SLEEP
STAGES

16. Sleep Onset
 Sleep begins at sleep onset even before a person reaches stage I NREM sleep
 heaviness and drooping of the eyelids
 clouding of the sensorium
 inability to see, hear or perceive things
in a rational or logical manner
 The person at this moment has no control of his brain and cannot respond logically and
adequately

17. Stages of Sleep
There are two general stages of sleep;
1. Rapid Eye Movement (REM) Sleep
2. Non-Rapid Eye Movement (NREM) Sleep

19. Non-REM Sleep
Stage I
• Light sleep
• Eyes &
muscle
activity slows
• 3-8% of sleep
time
Stage II
• True sleep
• Stoppage of
eye
movements
• 40-50% of
sleep time
Stage III
• Deep sleep
or Slow-
wave sleep
(SWS)
• δ waves 20-
50%
Stage IV
• Deep sleep
or SWS
• No eye &
muscle
activity
• 20% of sleep
time
• δ waves >50%
American Academy of Sleep
Medicine (AASM)
now considered stage III & IV as
STAGE III

20. Sleep spindles K
complex
Alpha
waves
Theta
waves
Delta
waves

21. Evolution of sleep patterns with age
Newborns
Polyphasic, 16hrs/day, REM sleep : 50%,
Infants
3 months of age the NREM-REM cyclic pattern of adult
sleep is established
Preschool
Biphasic , 10hrs/day, REM sleep : 25%, high arousal
threshold
Adults
Monophasic, 8hrs/night, REM sleep: 25%, 40% reduction in
the time spent in the stage 3 & 4 of NREM & replaced by
stage 2
Elderly
Biphasic, marked attenuation of the amplitude of delta
waves , increased sleep fragmentation, Alzheimer's and
Parkinson's are characterized by decreasing amounts of
REM sleep as the diseases progress

22. REM SLEEP = Paradoxical sleep
The brain waves had a high frequency and low voltage = normal
awake state
 A desynchronized EEG - fast rhythms & θ activity, sawtooth
appearance
 20-25% of sleep time, in infants it is about 40%

23. REM sleep can be subdivided into two stages :
•Hypotonia or atonia of the major muscle
groups
•Depression of monosynaptic and
polysynaptic reflexes
Tonic
•Rapid eye movements in all directions
•Phasic swings in blood pressure & heart rate,
irregular respiration, spontaneous middle ear
muscle activity & tongue movements
•Few periods of apnea or hypopnea
Phasic

24. Dreams

25. Neurobiology

33. Insomnia is a sleep disorder that is characterized by difficulty
falling and/or staying asleep. People with insomnia have one
or more of the following symptoms:
Difficulty falling asleep
Waking up often during the night and having trouble going
back to sleep
Waking up too early in the morning
Feeling tired upon waking

34. Insomnia may be divided into three classes based on the duration
of symptoms.
•Insomnia lasting one week or less may be termed transient
insomnia
•short-term insomnia lasts more than one week but resolves
in less than three weeks
•long-term or chronic insomnia lasts more than three
weeks.

35. Transient and short-term insomnia
• Jet lag
• Changes in shift work
• Excessive or unpleasant noise
• Uncomfortable room temperature (too hot or
too cold)
• Stressful situations in life (exam preparation, loss
of a loved one, unemployment, divorce, or
separation)
• Presence of an acute medical or surgical
illness or hospitalization
• Withdrawal from drug, alcohol, sedative, or
stimulant medications
• Insomnia related to high altitude (mountains)
Causes

36. Chronic or Long-Term Insomnia
• Psychological
• Physiological
Psychological
• anxiety,
• depression
• stress (mental, emotional, situational, etc),
• schizophrenia, and/or
• mania (bipolar disorder)

37. Physiological
• Chronic pain syndromes
• Chronic fatigue syndrome
• Congestive heart failure
• Night time angina (chest pain from heart disease
• Acid reflux disease (GERD)
• Chronic obstructive pulmonary disease (COPD)
• Nocturnal asthma (asthma with night time breathing
symptoms
• Obstructive sleep apnea
• Degenerative diseases, such as Parkinson's disease and
Alzheimer's disease (Often insomnia is the deciding factor
for nursing home placement.)
• Brain tumors, strokes, or trauma to the brain

38. Medication Related
Insomnia
• Asthma preparations
• high blood pressure
• depression, anxiety, and
schizophrenia.
Other Causes
• Caffeine and nicotine
• Alcohol
• A disruptive bed partner
with loud snoring or
periodic leg movements

39. Complete
medical
history and
physical
examination
Sleep history
The Epworth
Sleepiness
Scale
Actigraphy A sleep diary

40. Stick to a sleep schedule
Get out of bed when you're not sleeping
Avoid trying to sleep
Use your bed and bedroom only for sleeping
Find ways to relax
Avoid or limit naps
Make your bedroom comfortable for sleep
Exercise and stay active
Avoid or limit caffeine, alcohol and nicotine
Avoid large meals and beverages before bed
Check your medications
Don't put up with pain
Hide the bedroom clocks

41. TREATMENT

42. Cognitive behavior therapy
Helps change incorrect beliefs and attitudes about sleep (e.g., unrealistic
expectations, misconceptions, amplifying consequences of sleeplessness);
techniques include reattribution training (i.e., goal setting and planning coping
responses), decatastrophizing (aimed at balancing anxious automatic thoughts),
reappraisal, and attention shifting.
Moderate-intensity exercise (should not occur just before bedtime)
Relaxation therapy : Tensing and relaxing different muscle groups; biofeedback or imagery
(visual and auditory feedback) to reduce somatic arousal; meditation; hypnosis
Sleep restriction (paradoxical intention therapy) Uses a paradoxical approach in which the
patient spends less time in bed .This state of minimal sleep deprivation eventually leads to
more efficient sleep
Stimulus control therapy :Avoid bright lights (including television); noise and temperature
extremes; and large meals, caffeine, tobacco, and alcohol at night
Minimize evening fluid intake; leave the bedroom if unable to fall asleep within 20 minutes;
limit use of the bedroom to sleep and intimacy

43.  Initiate hypnotic use with identifying and addressing specific behaviors, circumstances,
and underlying disorders contributing to insomnia
 Prescribe the lowest effective dose of the hypnotic
 Prescribe hypnotics for short durations (two to four weeks) and intermittently
 Avoid hypnotic use or exercise caution if patient has a history of substance abuse,
myasthenia gravis, respiratory impairment, or acute cerebrovascular accident
 Watch for requests for escalating doses or resistance to tapering or discontinuing
hypnotic
 Hypnotics should be discontinued gradually (i.e., tapered); physician should be alert for
adverse effects (especially rebound insomnia) and withdrawal phenomena
Guidelines for Prescribing Hypnotics

44.  Antihistamenics
 NAIDS
 Muscle relaxants
 Antidepressants: trazodone , miratzilpine ,. Amitryptiline
 Antiepileptics: gabapentine
 Mood stabilizers : valproate , olanzapine
 Antipsychotics : reperidone ,quatiapene

45. Insomnia
Medcications
AVOID BENZODIAZEPINES

48. An apnea, which is the
cessation of breathing for
at least 10 seconds, can
occur as many as 20 to 60
times within an hour
The quality of one's sleep is
greatly compromised
leading to numerous
health conditions and a
decline in the quality of life

49. Obstructive sleep apnea - the most common type.
Occurs when the soft tissue in the back of throat relaxes
during sleep, causing a blockage of the airway and
snoring.
Central sleep apnea - much less common type.It involves
the CNS. It occurs when the brain fails to signal the
muscles that control breathing. Seldomly snore.
Complex sleep apnea – combination of both.

52. Definitions
 Apnea Cessation of airflow for >10 s
 Hypopnea A reduction in but not complete cessation of
airflow to <50% of normal, usually in association with a
reduction in oxyhemoglobin saturation
 AHI The frequency of apneas and hypopneas per hour of
sleep; a measure of the severity of sleep apnea
 OSA and hypopnea Apnea or hypopnea resulting from
complete or partial collapse, respectively, of the pharynx
during sleep
 CSA and hypopnea Apnea or hypopnea resulting from
complete or partial withdrawal of central respiratory drive,
respectively, to the muscles of respiration during sleep
 Oxygen desaturation Reduction in oxyhemoglobin
saturation, usually as a result of an apnea or hypopnea

53. Loud and
chronic
snoring
Choking,
snorting, or
gasping
during sleep
Long pauses
in breathing
Daytime
sleepiness, no
matter how
much time
you spend in
bed

55. Mixed apnea

56. Symptoms

57.  overweight
 male
 over the age of 65
 black, Hispanic, or a Pacific Islander
 related to someone who has sleep apnea
 a smoker
 certain physical attributes - thick neck, deviated septum, receding
chin, or enlarged tonsils or adenoids.
 Allergies or other medical conditions that cause to nasal congestion

59.  Polysomnography is usually done to diagnose sleep apnea.
 There are two kinds of polysomnograms
 An overnight polysomnography test involves monitoring brain waves,
muscle tension, eye movement, respiration, oxygen level in the blood
and audio monitoring. Home monitoring respiratory test.
 They are painless tests.

60.  Mild Sleep Apnea is usually treated by some behavioral changes
 Losing weight, sleeping on your side
 oral mouth devices (that help keep the airway open) help to reduce snoring in three different ways.
 Some devices
 bring the jaw forward
 elevate the soft palate
 retain the tongue (from falling back in the airway and blocking breathing).

61. Moderate to severe Sleep
Apnea is usually treated with a
C-PAP (continous positive
airway pressure). C-PAP is a
machine that blows air into your
nose via a nose mask, keeping
the airway open and
unobstructed.
For more severe apnea, there is
a Bi-level (Bi-PAP) machine. The
Bi-level machine is different in
that it blows air at two different
pressures. When a person
inhales, the pressure is higher
and in exhaling, the pressure is
lower

62.  TRACHEOSTOMY
 UVULOPALATOPHARYNGOPLASTY
(UPPP)
 MANDIBULAR MYOTOMY
 LASER ASSISTED UVULOPLASTY
(LAUP)
 RADIO FREQUENCY (RF)
PROCEDURE OR SOMNOPLASTY
Unfortunately, at this time the
procedure is so new and is still
seen as an experimental
procedure.

64. What is RLS?
 Neurological disorder characterized by
 Uncontrollable, overwhelming urge to move leg (akathisia)
 Occur at night or when relaxing or at rest
 Movement → immediate relief of symptoms
 Movement stop → return of symptoms
 Ignoring symptoms → ↑ akathisia
 Difficulty falling & staying asleep → exhaustion & daytime fatigue

65. ETIOLOGY
 Related to dysfunction of basal ganglia circuits that use dopamine as neurotransmitter
 In the evening dopamine levels fall → symptoms of RLS are often worse in the evening &
night
 Brain iron depletion causes alteration of brain dopaminergic system .

66. TYPES
Primary RLS
• Idiopathic
• Gradual onset
• Before age 40-45
• Progressive with age
Secondary RLS
• 2ry to other conditions
• Sudden onset
• After age 40
•

67. 2ry RLS
Neurological
Medical
Drugs
✿ Multiple sclerosis
✿ Parkinson's
✿ Peripheral neuropathy
✿ Anaemia – iron & folate
✿ Uremia & renal failure
✿ Magnesium deficiency
✿ Hypothyroidism, DM
✿ Pregnancy
✿ Auto-immune - RA, celiac
disease, Sjögren’s syndrome
✿ Anti –nausea
✿ Anti –psychotic
✿ Alcohol
✿ Withdrawal from sedatives
or narcotic
✿ Ca channel blocker
May associated with these conditions

68. Diagnosis of primary RLS
Essential criteria
An urge to move the legs usually accompanied or caused by
uncomfortable sensations in the legs
The urge to move or unpleasant sensations beginning or worsening
during periods of rest or inactivity such as lying or sitting
The urge to move or unpleasant sensations are partially or totally
relieved by movements, such as walking or stretching, at least as
long as the activity continues
The urge to move or unpleasant sensations are worse in the evening
or night than during the day or only occur in the evening or night
Supportive features
Dopaminergic responsiveness
Presence of periodic limb movements in sleep or in wakefulness
Positive family history
Associated features
Usually progressive clinical course
Normal neurological examination in the idiopathic form
Sleep disturbance

69. Investigations
 Blood
 Fasting blood glucose
 Serum ferritin
 Folate
 Magnesium
 TSH,T3,T4
 Renal function
 Electromyography & nerve conduction studies

71.  abnormal movements or behavior
 intruding into sleep
 during the night intermittently or episodically
 without disturbing the sleep architecture

72.  5 – 12 years old
 abrupt motor activity arising out of
SWS during the first one third of
sleep
 < 10 minutes
 complex behavior, nonsensical talking,
eyes are commonly open
In the 2nd sleep cycle

73.  fearful, vivid, and often frightening
dreams, mostly visual but sometimes
auditory, seen during REM sleep
 accompany sleep talking and body movements
 Begin 3-5 years

74.  SE of certain medications
 sudden withdrawal certain drugs
 Reassurance
 behavioral or psychotherapy
 REM sleep-suppressant medications

75. 1. Excessive daytime sleepiness
2. Cataplexy
3. Hypnagogic hallucination
4. Sleep paralysis.
Narcolepsy is characterized by the classic tetrad of:

76. Incidence
US : 1 over 2000
Japan : 1 over 600

77. Etiology
Defect in
hypocretin
• Autoimmune reaction
• Genetic predisposition

78. Diagnosis
Clinical evaluation
Lab test:
1. Multiple sleep latency
tests
2. Blood test for a type of
HLA
Specific
questionaires

82. Symptoms
 Difficulty initiating sleep
 Difficulty maintaining sleep
 Nonrestorative sleep
 Daytime sleepiness
 Poor concentration, learning problem
 Impaired performance, including a decrease in cognitive skills
 Poor psychomotor coordination, depression
 Headaches
 Gastrointestinal distress

83. INITIALLY
-reviewing your
symptoms
-taking a medical
history
-performing a physical
examination
SLEEP LOGS
SLEEP STUDIES EPWORTH
SLEEPINESS SCALE
ACTIGRAPHY

84. •Chronotherapy
•Bright light therapy
•Enhancing environmental cues
Behavioral
Treatment
•Sleep hygiene (avoid
napping,sleep & wake up on
same time each day, etc…)
Promoting A
Sound Sleep
•melatonin
•Melatonin receptor stimulantMedication

85. Outline
 Sleep history
 Clinical examination
 Investigation

86. Sleep history
 Patient bed time, time taken to fall asleep and duration of sleep
 Sleep position
 Detailed history of daytime sleepiness and how it affects individual
quality of life
 How patient feels upon awakening
 Any sleep behavior
 Other history
 History of CVD, nasopharyngeal problems, cerebral vascular disease
 Family history:
 Sleep apnea syndrome
 Narcolepsy
RLS

87. Clinical examination
 Mainly focus on:
 Respiratory system
 CVS
 GIT
 Endocrine
 Neurological

88. Investigation
1. Polysymnography (PSG)
2. Multiple sleep latency test (MSLT)
3. Maintenance of wakefulness test (MWT)
4. Actigraphy
5. Others

89. 1. Polysomnography
Sleep-related
breathing disorders
 Obstructive sleep
apnea
 Central sleep
apnea syndrome
 Obesity
hypoventilation
syndrome
 Upper airway
resistance
syndrome
Neurologic and
movement disorders
 Periodic limb
movement disorder
 Seizure disorders
 Parasomnias such as
 — sleepwalking
 — nocturnal
movements
 Narcolepsy or
hypersomnolence
 REM-behavior
disorder
Therapeutic indications
 Continuous positive
airway pressure
titration
 Assessment of
adequacy of sleep-
related interventions
 Respiratory
insufficiency (that is,
amyotrophic lateral
sclerosis) and the
titration of
noninvasive
ventilatory support
Indication

90. Polysomnography
This test records several body functions during sleep
 brain activity
 eye movement
 oxygen and carbon dioxide blood levels
 heart rate and rhythm
 Respiratory rate and rhythm
 The flow of air through your mouth and nose
 Snoring
 Body muscle movements
 Respiratory effort: Chest and abdominal movement
Principle

91. Brain activity (EEG): Sleep time, stages of sleep(NREM and REM),
and awake time
Abnormal brain activity (such as a seizure) is
noted.
Eye movement (EOG): Slow eye movements are present at the
start of sleep and change to rapid eye
movements during REM sleep.
Muscle movement (EMG): Leg jerking or other abnormal muscle
movement
Blood oxygen (O2) level: Blood O2 level is greater than 90% in normal
Heart rate and rhythm (ECG): Heart rate changes (arrhythmias), such as
an abnormally slow or fast heart rate, are
noted.
Breathing effort (RDI): Reduced air flow (hypopnea) or no air flow
(apnea) to the lungs occurs fewer than 5
times in 1 hour in normal
Chest and abdominal movements: Observe for abnormal chest and abdominal
movement throughout the study.
Audio and video recordings: Observe for restful or disturbed sleep such as
night terrors, sleepwalking, and sleep
talking.
Snoring monitor: Observe for excessive snoring or abnormal
snoring patterns.
More than 5 times in an hour mean
the patient have sleep apnea
Epileptiform ECG finding diagnose
seizure
If present diagnose parasominia of
corresponding type.
Finding

93. 2. Multiple sleep latency test (MSLT)
 Patient complaining or suspected of having excessive daytime
sleepiness (EDS)
Indication

94. Multiple sleep latency test (MSLT)
 It is a nap study.
 The test consists of four to five daytime EEG, EMG, and EOG
recordings at 2-hour intervals
 Each recording lasting for a maximum of 20 minutes
 The test measures
 The average sleep-onset latency
 The presence of SOREMs (timed from sleep onset to the first REM sleep)
Principle

95.  Patient is placed in a darkened room and asked to lie back, relax,
and to sleep if they feel like it.
 They are allowed 20 minutes to achieve sleep
 The time to falling asleep and the type of sleep that the patient goes
into is determined
 This is repeated for 4 to 5 times at interval of 2 hours
How it is done?

96. Normal Abnormal
More than 10 minutes to
fall asleep
Mean of 5 minutes to fall
asleep
At most, one nap episode
with REM sleep in 4 to 5
naps opportunity
Two naps or more with
REM sleep in 4 to 5 naps
opportunity is indicative of
pathology
Finding

97. 3. Maintenance of wakefulness test (MWT)
 Variation of MSLT
 The principle is the same with MSLT except
 Patient adopts a semireclining position in a chair and is instructed to resist
sleep
 If the patient fall asleep, the time from lights out to the onset of sleep
for each nap is recorded
Principle

98. Normal Abnormal
Will not falling asleep in
less than 25 minutes after
light off
Falling asleep less than 25
minutes
The MWT is of most value in determining the
effects of treatment to relieve daytime
sleepiness.
Finding

99. 4. Actigraphy
 Is a technique of motion detection that records activities during sleep
and waking
 It complements a sleep diary or sleep log data.
 The actigraphic instrument worn generally on the wrist and ankle for
1-2 weeks.
 It is a cost-effective method for assessing a sleep-wake pattern.
Principle

101. Actigraphy
 circadian rhythm sleep disorders
 sleep-state misperception
 other types of insomnia.
 To detect and quantify PLMS
Indication

102. Other investigation
 Thyroid function test to confirm hypothyroidism
 Liver functions
 Biochemical screening done in patient with RLS to exclude renal impairment and
chemical abnormality

103. References
 http://www.patient.co.uk/doctor/Restless-Legs-Syndrome.htm
 http://www.ninds.nih.gov/disorders/restless_legs/detail_restless_legs.h
tm
 http://www.hkresp.com/index.php/administrator/93-sleep-
medicine/337-2008-restless-leg-syndrome-an-overview
 http://help-me-to-sleep.com/restless-leg-syndrome/
 http://www.restlesslegs.com/hcp/diagnose-restless-legs-
syndrome.html>
 http://www.nhs.uk/Conditions/Restless-leg-
syndrome/Pages/Causes.aspx
 http://www.medicinenet.com/sleep/article.htm#stages
 http://www.sleepdex.org/stages.htm

104. Thank you