Does the InAlyzer2 measure muscle mass?

DEXA is known for measuring bone mineral density (BMD) and body composition (BMC, FAT, LEAN) in laboratory animals, but it can also help with an estimate of muscle mass.

While DEXA doesn’t directly measure muscle mass, it provides estimates of lean mass, which is a good indicator of muscle mass in studies of body composition.

Any DEXA based technology will output: %Fat, %Bone. Anything other than these two is considered %Lean, which includes muscles, organs, and water. Muscle doesn’t absorb X-rays differently than other non-fat soft tissues.

A conversation about the isoflurane ventilation came up. With this chamber, how do you reduce or ensure the reduction of exposure to isoflurane when using?

The majority of our InAlyzer2 DEXA users have two tubes that are inserted into the system via the inlet hole: one tube is for gas supply and the other is the waste scavenge tube.

Very few users use an external scavenger that is outside the door. Essentially, that is a giant vacuum hose that faces the door so that when the door is opened (swings open like your conventional home oven), the air is sucked up by the scavenger. READ MORE.

The best suggestion would be to reach out to the vendor of a lab’s existing isoflurane system and they certainly would have the double hose option (hose within a hose) or separate scavenger hose.

The only restriction we have is that our inlet hole for gas hoses is 25mm in diameter, so the outer diameter of whatever hose(s) must be smaller so it fits inside the system.

Is it possible to scan the mice without the introduction of isoflurane use in the InAlyzer itself? For example, if there is a separate induction chamber, can the mouse be anesthetized, then placed in the scanner, and finally returned to its home cage before it recovers?

It is very unlikely for this approach to be successful because the benefit of using isoflurane is that animals are quick to wake up, which allows for easier recovery from sedation. That same benefit would hinder returning the mouse to its cage prior to waking up.

The recommended InAlyzer 2 scan time for live animals is 84 seconds long. This mode allows the software to compensate for breathing movements. We do have a shorter 28 second scan intended for ex-vivo samples, but we don’t recommend this for live animals.

Even 28 seconds + processing time would be too short for animals to remain still without isoflurane.

A fume hood is most likely not necessary unless your IACUC safety requires it.

If you have a hose inside the system to also act as an exhaust through the provided inlet opening, this is sufficient. This exhaust hose could be snaked into the fume hood, or to a charcoal basin provided by isoflurane companies.

One alternative – instead of isoflurane, use ketamine as anesthesia. There is no hose set up required for this as injections are subcutaneous.

What is the main difference between the “M” and “S” model? Is the M just a little larger for mouse and rat use?

The box and weight for both models is the same, but the scanning areas vary, as shown here:

• DEXA InAlyzer2, Model S, Scan area 8.27in x 5.51in for small animals
• DEXA InAlyzer2, Model M, Scan area 8.27 in x 12.4 in for mid-sized animals

Is it possible to use a laptop instead of a PC if short on space?

We advise against laptops because there often can be communication issues between the scanner and the laptop (which happens via Ethernet cable).

The PC we supply is very small, about the size of a small two-bread toaster oven.

The monitor can be placed on a swivel hinge attached to the table or atop the scanner. The PC can be placed behind the scanner or on the floor.

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Contact Raj if you would like an installation guide for detailed specifications or to set up a short Zoom demonstration of the InAlyzer2 DEXA scanner.

READ MORE about the InAlyzer2 DEXA.