Investigations of sleep disorders

BY

Dr.Jaidaa MekkyLecturer of NeuropsychiatrySleep Medicine Consultant

Member of the American Academy of NeurologyMember of the American Academy of Sleep

Medicine

Faculty of MedicineAlexandria University

Background

• One-half to one-third of life asleep

• Sleep medicine relatively new field

• Sleep is a co-morbidity in a long list of diseases

• It was mentioned in the holy Quran 9 times, describing the sleep fnctions and stages

  : فذلك ،� وجعا %ب يسب المزمنة األمراض فى النوم كان إذا قال أبقراط إن وقالالموت عالمات .من

Milestones

• 1837 – Dickens – describes overweight/hypersomnolent boy in the Posthumous Papers of the Pickwick Club (term “pickwickian” used by Osler)

• 1875 – Caton – EEG in dogs• 1928 – Berger – Human EEG alpha waves• 1937 – Loomis – EEG Sleep stages

described

Milestones• 1953 – Aserinsky & Kleitman – REM sleep

• 1970s – Polysomnography

• 1972 – Guilleminault – coins term OSA

• 1990 – International Classification of Sleep Disorders

Sleep Physiology

• What is Sleep?– “a reversible behavioral state of perceptual

disengagement from and unresponsiveness to the environment”

• 75% in Non-REM sleep

• 25% REM sleep – muscle atonia, autonomic activation

Sleep Architecture: NREM & REM Sleep

Pace-Schott EF, Hobson JA. Nat Rev Neurosci. 2002.

Biological rhythms (periodic physiological fluctuations)

Types of rhythms

1. Ultradian (Basic Rest-Activity Cycle)2. Circadian (sleep-wake cycle)3. Infradian (menstrual cycle)4. Circannual (annual breeding cycles)

A major input to the relay and reticular nuclei of the thalamus (yellow pathway) originates from cholinergic (ACh) cell groups in the upper pons, the pedunculopontine (PPT) and laterodorsal tegmental nuclei (LDT). These inputs facilitate thalamocortical transmission. A second pathway (red) activates the cerebral cortex to facilitate the processing of inputs from the thalamus. This arises from neurons in the monoaminergic cell groups, including the tuberomammillary nucleus (TMN) containing histamine (His), the A10 cell group containing dopamine (DA), the dorsal and median raphe nuclei containing serotonin (5-HT), and the locus coeruleus (LC) containing noradrenaline (NA). This pathway also receives contributions from peptidergic neurons in the lateral hypothalamus (LHA) containing orexin (ORX) or melanin-concentrating hormone (MCH), and from basal forebrain (BF) neurons that contain γ-aminobutyric acid (GABA) or ACh. Note that all of these ascending pathways traverse the region at the junction of the brainstem and forebrain where von Economo noted that lesions caused profound sleepiness.

Sleep architecture over the lifespan

The main sleep c/o:

• Insomnia

• EDS

• Parasomnia

• Symptoms of SDB(snoring)

ApproachSleep history( SLEEP LOG)( from the patient & bed partner)Medications ( hypnotic dependant sleep

disorder)Medical history( COPD, Hypothyroidism,

end organ failure)Neurological ( Parkinson,s disease,

dementia)Psychiatric ( depression, anexiety)Social history( marital ,social &

occupational functioning)

Sleep Diary

Sleep Log

Epworth sleepiness scaleSituation Chance of dozing

Sitting and reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Watching TV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sitting, inactive in a public place (e.g. a theatre or a meeting) . . . . . . .As a passenger in a car for an hour without a break . . . . . . . . . . . . . . .Lying down to rest in the afternoon when circumstances permit . . . . .Sitting and talking to someone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sitting quietly after a lunch without alcohol . . . . . . . . . . . . . . . . . . . . . In a car, while stopped for a few minutes in the traffic

Total . . . . . . . . . . . . . . . . . . . . . . . .

Score:

0-10 Normal range10-12 Borderline

12-24 pathological

Examination

• Body habitus( obesity, poor hygiene)• Neck( circumference ,thyroid etc.)• Craniofascial abnormalities

(retrognathia, craniosynsitosis)• Otolaryngeal examination( nasal

mucosa, tongue ,uvula)• Pulmonary & cardiac examination• Neurological & Psychiatric assessment

Mallampati classification

InvestigationsLaboratory Tests:

Thyroid functionSerum ferritin, hemoglobinHLA typing(HLA DQB1*0602 )Toxocological screeningLiver & kidney function

Investigations( cont.)Neurologic Assessment:Videomonitored EEGImaging Studies: CT& / MRI

Assessment of the upper airway

• Fluoroscopy

• Nasopharyngoscopy

• Cephalometry

• CT, Volumetric reconstruction

• MRI

Investigations( cont.)

Sleep TestsSleep Tests•Overnight PolysomnographyOvernight Polysomnography

) )VideomonitoredVideomonitored((•MSLTMSLT•MWTMWT•ActigraphyActigraphy•OSLER testOSLER test

Polysomnography

Polysomnography is a simultaneous recording of multiple physiologic parameters related to sleep and wakefulness

– EEG – EOG – EMG

Aapplication

Parameters monitored: 1-Four (EEG) channels2-Two (EOG) channels 3-One (EMG) channel4-Airflow( nasal and

oral) for the detection of apnea

5-Sound recordings to measure snoring

6-ECG 7-Pulse oximetry 8-Respiratory effort

(Thoracic and abdominal belts)

9- Tibialis anterior EMG10-Detector of the body

position 11-Esophageal

manometry

Videomonitored PSG

Neurologic monitoring Techniques

• Extended EEG ( 12-36) channel

• Repeated studies ,video monitored

DD:

• Nocturnal seizures

• Parasomnias

• REM behavioral disorders

Hypnogram

Standard Hypnogram

PositionLeft

Right

Supine Prone

Upright

PLMS

With Arousal

W/O Arousal

Respiratory EventsMixed Apnea

Obstructive Apnea

Central Apnea

Hypopnea

Staging

Stage 4Stage 3Stage 2Stage 1

REMAwake

Movement Time

06 ã05 ã04 ã03 ã02 ã01 ã12 ã11 Õ

The main data presented in PSG are:

• 1) Total sleep time, wake time, total recording time;• 2) Sleep efficiency (total sleep time/total recording time);• 3) Latency for sleep onset, latency for REM sleep and other sleep

stages.• 4) Duration (in minutes) and proportion of total-sleep-time sleep

stages (5) Frequency of apneas and hypopneas per hour of sleep • 6) Saturation values and events of oxyhemoglobin desaturation • 7) Total number and index of periodic lower limb movements per hour

of sleep.• 8) Total number and index of micro-arousals per hour of sleep and

their relationship with breathing events or lower limb movements;• 9)Esophageal ph anormalities• 10)Penile tumecence

Portable PSG

MSLT -MWT

• 4-6 naps with 2h interval• Parameters monitored:• EEG(4channel)• EOG• Chin EMG• ECG• Respiratory flow (if needed)• Microphone (if needed)

GERD

Actigraphy

Actigraphy

• Cost efficient

• Records motor movements

• Aallows estimates for several days, avoiding the sampling error of NPSG

• It gives an idea about TST,SL, Nocturnal arousals

• It is superior to sleep log

Uses:

• Used in assessment of Insomnia

• Useful in children and old age

• Circadian rhythm disorders

• Epidemiologic sleep studies

Limitations:

• It is not standardized yet for diagnosing PLMS,SDB or RBD.

Osler testThe Oxford Sleep Resistance Test

Sleep tight