This 'smart' needle senses tissue density to inject the perfect spot

Researchers with Brigham and Women's Hospital have developed a type of 'intelligent' needle that senses different tissues in order to inject the right spot. Called the intelligent-injector for tissue-targeting (i2T2), the needle is designed for delicate injections that require experts to place the needle in exactly the right spot or risk injecting the wrong tissue.

Though many people think of injections as quick jabs to the arm, there are many instances where a needle must be navigated in a very delicate area or the injection site is very slim. In these cases, highly trained professionals must rely on their expertise to perform the injection, but mistakes can still happen.

To help deal with these delicate injections is the i2T2 needle, which has a built-in sensor to detect the density of different tissues it passes through. The needle can be set to detect the density of the tissue is needs to inject, helping avoid issues with either under- or over-shooting the injection site.

The study highlights one particularly difficult injection site: the suprachoroidal space in the back of the eye. Injecting this tissue is difficult due to its less than 1mm thickness, but missing the spot may cause damage to the retina. There are other delicate injections that require precision, however, including epidurals.

The smart needle has been tested with animal models and was found to prevent over-shooting issues. No additional training or special techniques were needed to use the needle for precise injections. Additional pre-clinical work will be necessary before moving toward human use, however.