Scoring of Self-Applied Somnography (SAS) studies in Noxturnal 6.3

Please contact us on sleepsupport@ru.is if you have any questions or need help!

The SAS system and the differences in scoring rules for EEG between the SAS and PGS are described in the following video: https://sleeprevolution.eu/en/sas-video/ Please start out by watching the video.

The SAS scoring procedure

Acceptable recording:

  1. At least 4 hours of sleep and with good quality EEG signal
  2. With valid signal from oximeter during the 4 hours mentioned
  3. With at least two out of three signals from
    • Cannula
    • Thorax belt
    • Abdomen belt

The downloaded recordings can be found in the recording library. Start by choosing an unscored recording, marked as “New” in the Status column, to work with (fig 1.). Double click on the recording to open it.

Figure 1
Figure 1: Choose the SAS recording you want to score from the recording library.

The work order you should use can be seen in our SR scoring layout (fig.2- SR SAS Scoring layout).

Figure 2
Figure 2: In the worksheet layout you can see 5 tabs that are in the following order: SAS-EEG, Respiratory, PLM sheet, Arousal and ECG sheet.

We have already have imported the SleepRevolution workspace (SR scoring layout). You can also set it up locally on your computer. See separate instruction “How to import SR ESADA scoring layout” link To select the correct layout you click on the icon as seen in Figure 3 and select SR ESADA scoring layout. IT IS VERY IMPORTANT TO USE THE SLEEP REVOLUTION WORKSPACE NOT THE ONE THAT OPENS AUTOMATICALLY!

Figure 3
Figure 3: SR scoring layout.

In the worksheet layout you can see 5 tabs that are in the following order: SAS-EEG, Respiratory, PLM, Arousal and ECG sheet. This is the same order as our scoring procedure, we start by scoring the EEG and arousals (sleep staging) in the first tab, then we score breathing events (the EEG channels and arousal scoring can be seen at the top the page), next up is scoring of leg movements and finally we classify the arousals (see fig. 2). It is easy to rearrange the signals within each tab if you want it to look the way you are used to but keep all filter settings like they are in the SR ESADA scoring layout.

The study opens automatically as “default-scoring -1” – you need to choose aSAGAalgorithm_uncertain. There are tabs on the right side of the screen and one of them is called “Scoring” – you click on the tab and there you can chose the correct scoring file to work on, you can then or later save the scoring as shown in point 9 below.

1. Start by running automatic analysis (it is needed for the respiratory and arousal scoring): Analysis → “Nox SAS and Respiratory Analysis” (fig. 4). It will not overwrite the previous sleep staging.

Figure 4
Figure 4: Nox SAS and Respiratory analysis.

2. Adjust the timeframe (start and stop times for the correct analysis period) on the Recording results tab by dragging the analysis start and stop bar on each side of the study overview, this can be adjusted further when you are in the scoring tabs.

3. Score sleep epochs marked as “_uncertain”. Other parts should not need editing but ok to do a quick review. (tab: SR SAS EEG), see fig 5.

Figure 5
Figure 5: Grey areas appear as “uncertain” epochs in the EEG sheet.

4. Score respiratory events using the recommended rules by the latest AASM version (currently v.3.0). (tab: SR Respiratory)

5. Score LM events (tab: SR PLM)

6. Use Tools → Update PLM (PLM events are made from the LM events where appropriate) (fig 6). LM events that are counted in the PLM series are changed to PLMS events, whereas those that are not a part of the series are still labelled as LM events (they don´t fit the criteria and are therefore not counted in the series, like an event that occurs during a respiratory event). See fig.7 and text below for clarification. Unmark the “starting in a movement event” when running the Update PLM tool (fig. 8) since it often causes many actual LM events to be left out.

Figure 6
Figure 6: Under Tools you can update PLM.
Figure 7
Figure 7: The light-green labelled events are PLMS events. One LM event (purple) is seen, and that one is less than 5 sec from the start of the prior event and therefore not counted as a part of the PLM series (grey bar seen between the right and left leg).
Figure 8
Figure 8: Update PLM settings.

7. Use Tools - > Arousal Tool (fig. 9) (arousals are classified: respiratory arousals, LM arousals, PLM arousals). Before running the tool change the <5 by clicking on the number and write 10 instead (fig.10).

Figure 9
Figure 9: Under Tools you use the Arousal Tool.
Figure 10
Figure 10: Arousal Tool settings.

8. Review the arousals in the arousal classification tab to review if the arousals are correctly classified and correct if needed (SR Arousals).

9. To save the scoring choose: “Save scoring as”: use your initials (fig. 11) and be careful to save it in the end so there is not “(modified)” behind your initials.

Figure 11
Figure 11: Save scoring.

10. In the “Recording Results” tab change the status of the scored recording from “New” to “Scored” (fig. 12). This will help you keep an overview of your scored studies in the recording library.

Figure 12
Figure 12: Set the appropriate status of the scoring.

11. Reports: see separate instructions.

12. To end scoring chose File → Close & Save Workspace (fig. 13).

Figure 13
Figure 13: Close and save workspace.