Hopefully you can help me with a query of mine. I’m currently intersted in purchasing an Embla N7000 EEG/PSG with all relevant software (Sandmand Elite) and hardware. This would be used to perform a private study on multiple areas of sleep phenomena and hopefully capture the events. It would possibly be the longest sleep study of it’s kind.
Although I would consider myself well versed techinically, I don’t actually work in medical care.
Technically the EEG would fall under consumer use.
I wondered if you could help me regarding the legalities of EEG/PSG recording at home, and whether there would be any issues on that front. I undestand that EEG’s generally fall under a medical grey when it comes to medical device regulations.
I have attempted to enquire about this through the United Kingdoms (where I’m based) MHRA (Medicines & Healthcare Products Regulatory Agency) but have yet to garner a response.
Thanks wjcroft, for the quick reply and informative post. I checked out a few of your links and they seem interesting. It’s reassuring to hear that EEG’s do fall under consumer use. If you would be able to answer one more specific question that would be grand.
I noticed that most of the links you attached seemed to be directed towards scientific as well as consumer study use.
Considering that the Embla N7000 is marketed and sold specifically as an hospital/laboratory device would there be any difference in attaining one for personal use? (I’m drooling at the 60 channels…)
It depends on the company from which you are buying the unit. In the case of medical or clinical equipment, some manufacturers only sell to licensed health practitioners or clinics. You can sometimes get around this by saying that you are going to use it for a research study at such and such an institution or lab.
Also if the equipment you are purchasing is sold on the used equipment market, then they usually are less picky about who they sell to.
Regarding this particular N7000 unit. Although the 60 channel capability looks wonderful, note that they provide no sort of “quick and easy” application cap for sleep usage. Many sleep studies are done by applying the electrodes one by one, and then sealing the electrode to skin interface with some type of binder such as collodion. So in a real sleep lab a tech would apply this to the client’s head, taking maybe 15 or more minutes for a standard set of electrodes. With 60 electrodes, that is an enormous task to do nightly.
There might be some type of dry contact elastic caps that would be much more pleasant. But unclear how they perform in sleep with your head rolling around on the pillow and increasing / decreasing the skin pressure over time.
The equipment would be used, although only (they say) used on a handful of private tests. Hopefully I’ll be able to get round this by conversing that it will be used for a research study.
I completely understand and agree that placing 60 electrodes per night would be a times and probably frustrating task. Admittedly the initial amount of electrode placement would be around the 10-20 guidelines, looking at around 24 channel. I need the extra channels for ECG placements etc. As the study continues, depending on the available data I might set to increase the amount of channels and placements.
The study that I am planning to perform would require 24/7 (or as close to) recording for a number of months, so I’ll have to see how long the initial placements last before re-applying with collodian. I will probably have to re-attach electrodes a couple if not more of times a week, depending on signal quality etc.
Thanks again for your detailed input, wjcroft, it’s greatly appreciated.
I wondered if you could help with another query of mine. I thought I would continue to use this thread rather than create another.
Could the Embla N7000 unit also be used as an ambulatory unit if it were still connected to the relative computer with all leads etc? From my understanding the software might also require an active internet connection, but if that were still permanent would there be any issues?
I attempted some research on google about this, but have struggled to gain any significant documentation.
Hi, I think you said on your original post that this was for sleep studies? What do you mean by ‘ambulatory’? EEG signals can acquire substantial artifact from cable movement and head position changes.
Did you try contacting the manufacturer? All the EEG equipment I am aware of, operates just fine without an active internet connection; by recording samples onto local disk storage. Some apps and equipment do allow cloud storage, but I’m guessing this would be an option rather than a requirement.
It would indeed still be used for a sleep study, but the study will continue into the day as a way to detect any abnormal activity. The definition of ambulatory would be to use the EEG/PSG during the day, going about normal day to day activity.
Some amplifiers as I’m sure you’re aware contain battery packs for this purpose. I can’t say that I have called the company yet, but I did look a their available documentation and it does not state ambulatory for use.
As for the internet connection and EEG equipment, that would be fine. It would be the software that might require a permanent connection, although the infomation seems here and there regarding that. Internet connection wise, there are plenty of portable ways around that of course.
The photo shows a “bedside” unit that looks pretty large and heavy. It connects to a “patient” unit (also called a head-box), with the EEG leads. Since this uses individual EEG leads to the head-box, there will be substantial cable movement if you are walking around. I doubt that this is your best bet if you are looking for 24 hour ambulatory usage.
I had a look at the aformentioned product, it definitaly seems interesting. Would it be able to record PSG? My other concern would be if this product works with either REMlogic, Sandman Elite, or Rembrant 9.1 software which are considered the standard for scoring and automatic sleep stage reporting. Everything software wise appears to be proprietry use from leading manufacturers which makes things difficult.
I’m going to look into this and do a bit more research. I wonder if there would be a way to limit cable movement if everything was strapped and worn with potentially customized holders.
Once again, thanks for the valuable reply. I’ll look into gtec more too.
Edit: To confirm the most important data will be collected at night, for a minimum of at least 12 hours. If I can manage to obtain/slightly modify something that would allow at least a few hours of out of bed/outside ambulatory movement that would be perfect.
Natus do create a product similar for this purpose. http://www.natus.com/index.cfm?page=products_1&crid=809
but it’s only 24 channels, and only works with their SleepWorks software, which to me, doesn’t seem as user friendly as Remlogic or Rembrant 9.1, or does it appear to contain any form of automatic sleep staging report, which would absorb a huge amount of manual data analyses for me.
Implies that PSG can be done with something around 24 channels. So 60 channels may be paying for more than you need. The photo in the article showing an ambulatory setup I found to be honestly daunting. Getting hooked up like that for more than a couple days would put a huge crimp in anyone’s lifestyle, that is for sure.
The g.tec link I provided is for EEG only. They do have a Mobilab unit that does various other biosignals. As you say, the processing of the collected data seems to be the most proprietary link, and may force selection of the corresponding hardware.
You’re right, a full Type 1 PSG can indeed be completed with 24 channels. 60 Channels would be quite specific and specialist I would imagine, but I would like to potentially keep the door open for extended and general EEG use as well. At the moment the price diference between 32 channel and 60 channel seems fairly negligible.
As for the all the wires on a daily basis, I can’t say I’m too phased by it. I would imagine there ways to increase comfort with certain customized support holders etc.
I had another brief look at g.tec, and although it seems interesting I’m not convinced it reaches my requirements for full PSG analyses.
There is another product that caught my attention a short while ago, and one that I’m considering.
Full wireless Type 1, PSG. I’d imagine this would be easier for (potential) ambulatory use, but the motion artifacts need addressing. Also, it’s batteries are only capable of recording 12 hours of continous recording before recharge. It might be possible to purchase batteries that can record for 24 hours of continous use, but I can’t confirm that.
Lastly, to those who are interested, there’s an interesting theses
(https://spiral.imperial.ac.uk/handle/10044/1/38556)
written by ‘Rajagopal, Mohan Kumar’, Imperial College London. He covers quite a number of areas on various PSG systems, and touched briefly on different types of electrode contacts, wet and dry, and even foam, some of which I recognise mentioned, Wjcrof.
I’ll do some more research and make a decision. The next line of interest will probably be what type of electrode contact to use.
Dr. Mark Hyman just completed presenting a free docuseries on how Functional Medicine can address a wide range of neurological and metabolic conditions. Not sure what led you to consider the considerable expense of long term PSG monitoring. But there are likely some experts out there who can work with underlying causes.
Functional Medicine is a new perspective on how the big picture integrated system influences overall health.
There are multiple abnormal and potentially unique, as well as poorly understood and undocumented sleep phenomena occuring. I’ve spoken to a few specialists in my country, and it’s clear that their knowledge is limited on a few specific areas of interest. I would personally like to capture and study these events, but for now I’m waiting until I obtain data from PSG analyses.
You certainly presented some interesting links, I can’t say I know or have heard much about Functional Medicine, but I’ll also look into that too.
As for the EEG/PSG to buy:
I’ve removed the Saphire Wireless PSG from my list. I’m unsure about the software and the documentation about the device on the internet is limited, meaning lack of resources for research.
I’m still highly interested in the Natus Embla N7000 Unit.
I am also very interested in Compumedics Grail EEG/PSG
I don’t think either of these are going to give you the ambulatory aspect you said you wanted. The Grail uses Power over Ethernet (POE), which requires generally a POE ethernet switch powered by a wall outlet. Not sure if there are any battery versions of this.
I looked at the spec sheet for the Grail. It mentions the 4K sample rate, but never directly. I assume they mean 4096 or 4000 sps for the 19 EEG channels. This is why they likely chose Ethernet for the fast transmission rate. But your sleep scoring doesnt really need that high a sample rate; might be useful for certain unusual brain conditions.
I’ve had to decide to cut off the ambulatory element for the moment which is dissapointing. But I could still manage 16 hours of recorded data per day which is still substantial. I’ll have to invest in a dedicated ambulatory EEG/PSG later, hopefully at a reduced price if new models are released.
I’ve decided on the Embla N7000 EEG/PSG. It’s slightly cheaper than Compumedics Grail counterpart and I like the documentation on RemLogic software, although Compumedics PSG Profusion 4 software does look equally as intuitive.
I know of a company that is also UK based for technical software support, which would be useful for me. 60 channels also allows of plenty of breathing room for expanded studies if required.
I’ve enjoyed the exchange of knowledge, wjcroft, so thank you for that. As siad previously, the next decision will be what type of electrode connection to use. I’ll probably attempt wet electrode placement initially.
I have both the Natus N7000 unit, and Natus Titanium unit now, with Rembrandt 9.1 and Remlogic software (although I will use remlogic). Both devices should work seamlessly with Remlogic.
I also purchased the Natus Grass Electrodes (https://stowood.com/product/genuine-grass-electrodes/) which to my knowledge are some of the best electrodes to buy.
They will be attached using the Weaver Ten20 conductive paste http://www.weaverandcompany.com/ten20.html
I also have the neccesary ECG leads and electrodes, as well as Pulse Oximetry, respiritory flow and effort belts.
