1 Copyright © 2014 Elsevier Inc. All rights reserved. Chapter 51 Neurologic Aspects of Sleep Medicine Renee Monderer, Shelby Harris and Michael Thorpy

2 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-1 The stages of sleep. A, Stage N1. There is low-voltage mixed-frequency electrocerebral activity with ongoing muscle activity and slow, rolling eye movements. B, Stage N2 sleep showing sleep spindles. K- complexes are also classically present but are not clearly shown in this epoch. C, Stage N3 sleep, with high- amplitude, low-frequency delta activity in the electroencephalogram (EEG). The eye-movement channels reflect the EEG. D, Stage REM. The EEG is of low amplitude and mixed frequency and is accompanied by muscle atonia and rapid eye movements. (Adapted from Abad VC, Guilleminault C: Polysomnographic evaluation of sleep disorders. p In Aminoff MJ (ed): Aminoff’s Electrodiagnosis in Clinical Neurology. 6th Ed. Elsevier Saunders, Oxford, 2012.)

3 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-2 Obstructive apnea. This 2-minute screen shows complete cessation of airflow for at least 10 seconds, accompanied by persisting respiratory efforts of the thoracic (Thor Effort) and abdominal muscles (Abdo Effort). The associated oxygen desaturation (Desat) is not essential for the events to be scored as obstructive apnea (Ob.A). (From Avidan A, Barkoukis T: Review of Sleep Medicine. 3rd Ed. Elsevier, Philadelphia, 2012.)

4 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-3 Obstructive hypopnea (Hyp). This 2-minute screen shows airflow reduced by about 50 percent from baseline. There are persisting respiratory efforts of the thoracic (Thor Effort) and abdominal muscles (Abdo Effort), and a decline of more than 3 pecent in oxygen saturation. CPAP, continuous positive airway pressure; Desat, desaturation. (From Avidan A, Barkoukis T: Review of Sleep Medicine. 3rd Ed. Elsevier, Philadelphia, 2012.)

5 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-4 Actogram of a patient with severe delayed sleep phase disorder (DSPD). A, Actogram derived from actigraphy data obtained over 9 days. The yellow lines depict light exposure. The high-amplitude dense bars are representative of wakefulness, and time with little or no activity represents sleep. The average sleep onset is at 5 to 6 a.m. and wake time is from noon to 1 p.m. Note the stable delay of the sleep-wake rhythm in relation to the conventional sleep time and wake-up time. B, The 24-hour rhythm of plasma melatonin levels in this patient. The dim-light melatonin onset (DLMO) was defined as an absolute threshold at 10 pg/ml. The DLMO of this patient is delayed, at 1:23 a.m. (which is approximately 5 hours later than expected in nondelayed persons).

6 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-5 Actogram of a patient with severe advanced sleep phase disorder. A, Actogram derived from actigraphy data obtained over 9 days. The yellow lines depict light exposure. The high-amplitude dense bars are representative of wakefulness, and time with little or no activity time represents sleep. The average sleep onset is 8 to 9 p.m. and wake time is from 4 to 5 a.m. Note the stable advance of the sleep-wake rhythm in relation to the conventional sleep and wake-up times. B, The 24-hour plasma melatonin level rhythm of this patient. The DLMO was defined as an absolute threshold at 10 pg/ml. The DLMO of this patient is advanced, at 7:30 p.m. (which is approximately 2–3 hours earlier than expected in nonadvanced persons).

7 Copyright © 2014 Elsevier Inc. All rights reserved. Figure 51-6 Strategies to accelerate circadian adaption to jet lag. A, An example of a treatment strategy for jet lag associated with an eastward flight over six time zones (from Chicago to London). Adjustment requires an equal number of hours of phase advance. On arrival, the traveler should avoid bright light in the early-morning hours (before 9 a.m.) for the first 2 days so that light does not decrease before nadir of the core body temperature (which will induce a phase delay), and exposure to bright light after 9 a.m. to induce phase advances. In addition, melatonin, 1 to 5 mg taken at 6 p.m. local time on the departure day and at local bedtime (10 to 11 p.m.) on arrival for 4 days is helpful. B, Treatment strategy for jet lag associated with a westward flight over five time zones (from Chicago to Hawaii). The subject should be exposed to as much as light as possible in the late afternoon and early evening at the destination, which will result in the required phase delay.