Positive Occipital Sharp Transients of Sleep, Posterior slow-wave transients associated with eye movements and Occipital Slow Transients

Positive Occipital Sharp Transients of Sleep, Posterior slow-wave transients associated with eye movements and Occipital Slow Transients

By: Mohibullah Fazli KakarFrench Medical Institute for ChildrenKabul Afghanistan

Positive occipital sharp transientsof Sleep

Best seen at the age of 15–35 years and rarely <3 years. Seen in 50–80% of healthy adults. Amplitude 20–75 μV; duration 80–200 msec. Absent in individuals with poor central vision. Sharply-contoured, surface positivity, occurring in trains with a repetitive rate of 4–5 Hz, and monophasic checkmark-like waveform seen singularly or in clusters over the occipital regions.

Positive occipital sharp transientsof Sleep

Always bilaterally synchronous but are commonly asymmetric on the two sides. Asymmetry of 50% is normal. POSTS occur during deep drowsiness and stage 2 sleep. Rare in REM sleep.

Posterior slow-wave transientsassociated with eye movements

Seen in children age 6 months to 10 years, but most commonly in children aged 2–3 years. Consisting of a monophasic or biphasic slow transient with a duration of 200–400 msec and a voltage of up to 200 μV in the occipital regions. A latency of 100–500 msec is noted after the eyeblinks or eye movements. The initial component of the transient is surface positive. The ascending phase is steeper than the descending phase

Occipital slow transients

Physiologic waves presenting during non-REM sleep, especially a transition from light to deep sleep in infancy until 5 years of ageBilateral, isolated, medium- to high-amplitude, monomorphic, triangular-shaped, delta waves with a typical duration greater than 250 msec in the occipital regions. These waves vary from a cone-shaped confi guration (cone waves or “O” waves) to a biphasic slow transient. These transients occur every 3–6sec during light sleep and more frequently during deeper stages of sleep.

Positive Occipital Sharp Transients of Sleep (POSTs)

EEG of a 4-year-old asymptomatic male during drowsiness. Characteristics of POSTS includesharply-contoured, surface positive, occurring in trains with a repetitive rate of 4–5 Hz, and monophasic checkmark-like waveform seen singularly or in clusters over the occipitalregions. POSTS are always bilaterally synchronous but are commonly asymmetric on the two sides and should not be misinterpreted as epileptiform activity or focal nonepileptiformactivity.10,14 POSTS occur during drowsiness and stage 2 sleep.



EEG of a 3-year-old asymptomatic male during stage 2 sleep. Characteristics of POSTS are sharp-contoured,surface positivity, occurring in trains with a repetitive rate of 4–5 Hz, and monophasic checkmark-like waveform seen in singly or in clusters over the occipital regions. POSTS arealways bilaterally synchronous but are commonly asymmetric on the two sides and should not be misinterpreted as epileptiform activity or focal nonepileptiform activity.10,14POSTS occur during, drowsiness and stage 2 sleep.



POSTS (Box) can simulate epileptiform activity. Their triangular morphology, persistent lack of slow wave following sharp transients, positive polarity, constant symmetry, and occurrence during sleep differentiate them from epileptiform activity.


Asymmetric Posterior Occipital Sharp Transient of Sleep (POSTS)

A 7-year-old boy with recurring staring episodes and behavioral issues. The routine EEG during sleep shows bilaterally synchronous but asymmetric POSTS. Characteristics of POSTS are surface positivity, occurring in trains with a repetitive rate of 4–5 Hz, and monophasic checkmark-like waveforms. POSTS are always bilaterally synchronous but are commonly asymmetrical on the two sides and should not be misinterpreted as epileptiform activity or focal nonepileptiform activity.

Aymmetric Posterior Occipital Sharp Transient of Sleep (POSTS)

Pathologically Asymmetry of Positive Occipital Sharp Transients of Sleep (POSTS)

A 7-year-old girl born 24 weeks gestational age with grade 4 intraventricular hemorrhage (IVH). Subsequently, she developed spastic quadriparesis and global developmental delay. Cranial MRI showed periventricular leukomalacia with bilateral white matter involvement, greater on the left. Prolonged 72-h-video-EEG demonstrates persistent suppression of POSTS and anterior beta activity in the left hemisphere throughout the drowsy and sleep EEG recording. Although persistent asymmetric POSTS in this case are pathologic, physiologic POSTS can be quite asymmetric and may be present on only one side in the routine EEG. Therefore, asymmetric POSTS without other associated abnormalities should not be misinterpreted as abnormal

Pathologically Asymmetry of Positive Occipital Sharp Transients of Sleep (POSTS)

Posterior Slow-Wave Transients (Occipital Sharp Transients); Associated with Eye Movements

Posterior slow-wave transients associated with eye movements is an EEG pattern consisting of a monophasic or biphasic slow transient with a duration of 200–400 msec and a voltage of up to 200 μV in the occipital regions (*).The latency of 100–500 msec is noted after the eye blinks or eye movements. The initial component of the transient is surface positive. The ascending phase is steeper than the descending phase. This EEG pattern is seen in children age 6 months to 10 years, but seen most commonly in children aged 2–3 years. This EEG pattern is a normal phenomenon but may be misinterpreted as epileptiform activity



Posterior slow-wave transients associated with eye movements is an EEG pattern consisting of a monophasic or biphasic slow transient with a duration of 200–400 msec and a voltage of up to 200 μV in the occipital regions (open arrow). The latency of 100–500 msec is noted after the eyeblinks or eye movements. The initial component of the transient is surface positive. The ascending phase is steeper than the descending phase. This EEG pattern is seen in children age 6 months to 10 years, but seen most commonly in children aged 2–3 years. This EEG pattern is a normal phenomenon but may be misinterpreted as epileptiform activity



Posterior slow-wave transients associated with eye movements is an EEG pattern consisting of a monophasic or biphasic slow transient with a duration of 200–400 msec and a voltage of up to 200 μV in the occipital regions (*).The latency of 100–500 msec is noted after the eyeblinks or eye movements. The initial component of the transient is surface positive. The ascending phase is steeper than the descending phase. This EEG pattern is seen in children age 6 months to 10 years, but seen most commonly in children aged 2–3 years. This EEG pattern is a normal phenomenon but may be misinterpreted as epileptiform activity



Posterior slow-wave transients associated with eye movements is an EEG pattern consisting of a monophasic or biphasic slow transient with a duration of 200–400 msec and a voltage of up to 200 μV in the occipital regions.The latency of 100–500 msec is noted after the eyeblinks or eye movements. The initial component of the transient is surface positive. The ascending phase is steeper than the descending phase. This EEG pattern is seen in children aged 6 months to 10 years, but seen most commonly in children aged 2–3 years. This EEG pattern is a normal phenomenon but may be misinterpreted as epileptiform activity


Occipital Slow Transients; Cone Wave and Diphasic Slow Transient

In children, the transition from light to deep sleep may be associated with bilateral high-voltage slow transients in the occipital regions. These waves vary from a cone-shaped configuration (double arrows) to a biphasic slow transient (open arrow). These transients occur every 3–6 sec during light sleep and more frequently during deeper stage of sleep

Occipital Slow Transients; Cone Wave and Diphasic Slow Transient

Occipital Slow Transients; Cone Waves

In children, the transition from light to deep sleep may be associated with bilateral high-voltage slow transients in the occipital regions. These waves vary from a cone-shaped configuration to a biphasic slow transient. These transients occur every 3–6 sec during light sleep and more frequently during deeper stages of sleep.10 Cone waves or “O” waves (arrow) are physiologic waves presenting during non-REM sleep from infancy until 5 years of age. They are isolated, medium- to high-amplitude, monomorphic, triangular shaped, delta waves with a typical duration greater than 250 msec that occur over the occipital region

Occipital Slow Transients; Cone Waves

Occipital Slow Transients; Cone Wave

In children, the transition from light to deep sleep may be associated with bilateral high-voltage slow transients in the occipital regions. These waves vary from a cone-shaped configuration to a biphasic slow transient. These transients occur every 3–6 sec during light sleep and more frequently during deeper stage of sleep. Cone waves or “O” waves (arrow) are physiologic waves presenting during non-REM sleep from infancy until 5 years of age. They are isolated, medium- to high-amplitude, monomorphic, triangular shaped, delta waves with a typical duration greater than 250 msec that occur over the occipital region

Occipital Slow Transients; Cone Wave

Health & Medicine

Positive Occipital Sharp Transients of Sleep, Posterior slow-wave transients associated with eye movements and Occipital Slow Transients