Medical

Analysis of speckled laser light could help prevent heart attacks

Analysis of speckled laser lig...
Scientists are using a laser-equipped catheter to identify arterial plaque deposits (pictured) that may be about to rupture
Scientists are using a laser-equipped catheter to identify arterial plaque deposits (pictured) that may be about to rupture
View 2 Images
A close-up view of the catheter
1/2
A close-up view of the catheter
Scientists are using a laser-equipped catheter to identify arterial plaque deposits (pictured) that may be about to rupture
2/2
Scientists are using a laser-equipped catheter to identify arterial plaque deposits (pictured) that may be about to rupture

Heart attacks often occur when plaque deposits break off of blood vessel walls, subsequently blocking arteries that carry oxygen to the heart. A new imaging process could identify those unstable deposits, allowing them to be treated before they rupture.

Developed by scientists at Massachusetts General Hospital, the experimental "intravascular laser speckle imaging" (ILSI) technique utilizes a special small-diameter catheter, which is inserted into the blood vessel in question.

An optical fiber within that device emits laser light onto the vessel walls – that light is partially absorbed and partially scattered back by any plaque deposits it encounters. The scattered light forms a continuously fluctuating speckle pattern, which passes through a lens and onto a CMOS image sensor within the catheter.

Using a linked high-speed camera, it's possible to measure the rate at which the speckle pattern fluctuates over a given time period. If that rate exceeds a certain threshold, it means that the deposit is becoming loose and elastic in structure, and thus likely to rupture soon. Given that advance warning, physicians could then proceed to dissolve the plaque via medication, or surgically remove it.

A close-up view of the catheter
A close-up view of the catheter

The technology has already been successfully tested on human coronary arteries transplanted onto the hearts of live anesthetized pigs. Further animal studies are planned, after which human preclinical trials could begin.

"Reducing mortality from heart attacks in the general population requires a comprehensive screening strategy to identify at-risk patients and detect high-risk vulnerable plaques while they can be treated," says the lead scientist, Assoc. Prof. Seemantini Nadkarni. "By providing the unique capability to measure mechanical stability – a critical metric in detecting unstable plaques – ILSI is poised to provide a new approach for coronary assessment."

The research is described in a paper that was recently published in the journal Biomedical Optics Express.

Source: The Optical Society

4 comments
4 comments
paul314
Somebody''s going to have to be pretty high risk before you do that kind of catheterization. But you could still likely save lives by distinguishing the difference between "sometime soon" and "now".
Douglas Rogers
In the 90's, I epoxied a GRIN lens onto the end of a fiber optic to make a fiber optic pigtail to scan laser diode fields. Maximizing the signal was pretty much a miracle!
Don Duncan
Why not reverse plaque buildup by slowly dissolving it with Dr. Pauling's formula?
Jinpa
Why not just take a blood sample and analyze that using this equipment or some other method? As DVT problems prove, it doesn't matter where the clots come from.