RPSGT Technology & Tools 4

Question 1

The International 10-20 electrode placement system divides the head based on measurements that are what percentage of total skull dimensions?

Accepted Answer

10% and 20%

Answer

The 10-20 system uses 10% and 20% intervals of total nasion-to-inion and preauricular distances to place electrodes.

Question 2

Which electrode placement is used for the left eye's recording derivation (E1) in standard AASM PSG montages?

Accepted Answer

1 cm below and 1 cm lateral to the outer canthus of the left eye

Answer

AASM recommends E1 placement 1 cm below and 1 cm lateral to the left outer canthus to capture both horizontal and vertical eye movements.

Question 3

Respiratory inductance plethysmography (RIP) measures thoracoabdominal movement by detecting changes in:

Accepted Answer

Inductance of wire coils embedded in elastic bands

Answer

RIP bands contain sinusoidally wound wires whose inductance changes as cross-sectional area of the thorax or abdomen changes with breathing.

Question 4

A patient's PAP device data shows a residual AHI of 15 events/hr despite a fixed CPAP pressure of 12 cmH2O. The waveform pattern shows clustered events. This pattern is MOST consistent with:

Accepted Answer

Treatment-emergent central sleep apnea

Answer

Clustered central events emerging after initiation of CPAP therapy for OSA is the hallmark of treatment-emergent (complex) central sleep apnea.

Question 5

What is the primary purpose of using a reference electrode (e.g., M1 or M2) in EEG derivations during PSG?

Accepted Answer

To serve as the electrically inactive reference point for differential amplification

Answer

Reference electrodes (mastoids) provide a relatively electrically quiet site for differential amplification, allowing the active electrode's signal to dominate the derivation.

RPSGT Exam Practice Test

RPSGT Exam Practice Test

RPSGT Technology & Tools 4