Who could have imagined that kosher cow brains would help lead to the development of the CT scan, one of the most critical diagnostic tools in use today?
In fact, according to a recent article in the international radiological publication American Journal of Roentgenology, kosher bovines played a key role in the advent of the CT scan, an X-ray machine that rotates around the patient's body, yielding cross-sectional views.
Before CT (computerized tomography, formerly known as a CAT scan), many body parts were inaccessible to radiography.
The CT scan-kosher cow connection is "absolutely fascinating, intriguing," said Dr. Gerald Friedland, a professor emeritus of radiology at Stanford University School of Medicine and a co-author of the AJR article, which traces in detail the birth of the CT.
The little-known kosher cow story, part of that history, goes like this:
In the late 1960s, a team of doctors was working to perfect computer-assisted tomographic scanning. At that time, the machine was being formulated to reveal brain activity; later it was expanded to examine other parts of the body, as well.
To determine precisely what the CT could observe in the brain, British doctor Godfrey Hounsfield and South African doctor James Ambrose attempted to test the device on human brains that had been preserved in the chemical formalin.
The doctors had little luck. The formalin had hardened the brain tissues in such a way that they no longer resembled normal brain matter. Given that the CT scan would be used on living brains, the doctors needed to be able to test their instrument on brains of similar structure.
So the doctors decided to test the device on fresh cow brains, which they obtained from a local butcher in England, where the research was being performed.
The results were not what the doctors had hoped for. Before they kill the cows, British slaughterers use electric shock to stun them; law dictates that method as a way of preventing cruelty to animals. This process of stunning, however, causes the ventricles of the cow brain to fill with blood and also causes hemorrhages in the brain itself.
The blood in the brain obstructed the doctors' view; they had no way of seeing the nuances the CT scan was capable of showing.
"They were very disappointed," Friedland says of the researchers.
But then Ambrose, who is part Jewish, remembered that British law allowed shochets, or Jewish ritual slaughterers, to kill cattle by cutting the great vessel of the neck without first stunning the animals. This kosher method of slaughter drains blood away from the brain, thus preventing unwanted bleeding there.
Following Ambrose's hunch, the doctors examined the brains of kosher cows using the CT scan, and were the first to see the clear anatomic detail yielded by a CT scan of a fresh specimen of the brain.
"Without the kosher brains, they would never have tried it on a patient," says Friedland, a member of Congregation Kol Emeth in Palo Alto.
In January 1970, Ambrose and a team of doctors met to review the results of the CT scan thus far and agreed that the company EMI should build a head scanner. This decision paved the way for the first head CT scan on a patient, which took place in October 1971.
Since then, the CT scan's capabilities have expanded dramatically. "It has become an amazing tool," Friedland says.