Researchers at Imperial College London have developed ‘The Intelligent Knife’ also known as the sniffing scalpel.
Inventor: Dr Zolkan Takats
Device = Electrosurgical knife + mass spectrometer
How does it work?
The electrosurgical knife burns through tissue, creating smoke (a gaseous sample) which is carried through to a mass spectrometer; an analytical instrument.
A mass spectrometer is widely used in the chemical industry as it provides accurate data on the chemical composition of measured compounds on a graph such as those shown below.
There are numerous types of mass spectrometers which measure different types of samples; solid, liquid, gas. Essentially, the sample is ionised by breaking the compound into fragments which are charged. These fragments are then measured according to their mass:charge ratio, x axis in the graphs above, which can then be identified to prove its chemical composition. The peaks in the graphs, y axis, show the abundance of each fragment.
(This device in particular uses a Rapid Evaporative Ionisation Mass Spectrometer, REIMS)
This is a major breakthrough as it takes seconds for the analytical measurement to be completed. The readings are then matched against a reference library of cancerous and healthy cells. A traffic light signal is used to direct the surgeon whether or not to continue cutting.
On screen signal:
Red – Cancerous cells still present; keep cutting.
Green- Healthy cells present; stop cutting.
In its first study, with 81 cases, the iKnife proved 100% accurate. This device has cut down surgery time where it took ≤30 mins for lab results to analyse samples and increased efficiency as fewer patients require a second surgery for successful removal of cancerous tissue.
In the past, studies show that 20% of breast cancer patients required a second operation for complete success. The iKnife shows promising statistics to relieve patients from going under the knife several times. However, the device does not come cheap, at over £250,000 a piece. This could drop should it be commercialised for wider use.
We may see the iKnife being used for a whole range of tests soon as it can also detects the difference between horsemen and beef which could have prevented some scandals!
J. Balog et al. ‘Intraoperative tissue identification using rapid evaporative ionization mass spectrometry.’ Sci. Transl. Med. 5, 194ra93 (2013).