Globetrotting radiologist tackles hemorrhagic telangiectasia

February 4, 2004

For researchers confronting some rare, unusual diagnoses, building a case library could be the work of a lifetime. With electronic links to colleagues around the world and the ability to store images and information digitally for remote viewers, experts

For researchers confronting some rare, unusual diagnoses, building a case library could be the work of a lifetime. With electronic links to colleagues around the world and the ability to store images and information digitally for remote viewers, experts can share their findings more quickly than ever.

Dr. Robert White has focused his globetrotting career in interventional radiology on repairing complex arterial malformations. This work has taken him to Japan, Thailand, Italy, and Argentina.

"Medicine is a great nonpolitical, nonthreatening method of globalization that is especially needed for today's world," said White, former chair of radiology at Yale University.

White, director of the Yale Vascular Malformation Center, serves as chair of the scientific and medical advisory board of the Hereditary Hemorrhagic Telangiectasia (HHT) International Foundation. Since the creation of the Foundation in 1990, White has helped to develop a worldwide network of multidisciplinary centers that are devoted to the research and treatment of HHT, a hereditary disease characterized by malformations in the blood vessels.

HHT is a "rare but common" genetic disorder, White said. It affects about one in 5000 people. Men and women from all racial and ethnic groups are affected, but many practitioners are unfamiliar with the disease, and it is often undetected or misdiagnosed in its later stages as a stroke or brain abscess.

"Particularly in cases of less common diseases such as HHT, global collaboration is key in collecting data and working toward treatment," White said.

White and his colleagues have established HHT Centers in Italy, Canada, Denmark, England, Ireland, Japan, and Australia. The centers work together in tracking and treating HHT patients.

HHT causes an abnormality in a small percentage of the blood vessels: It creates blood vessels that lack connecting capillaries between an artery and a vein. As a result, arterial blood flows directly into a vein without first having to slow down while squeezing through the small capillaries. This high-pressure blood flow creates fragile places in the blood vessels that are prone to rupturing and bleeding.

An abnormal blood vessel of this kind is called a telangiectasia if it involves small blood vessels, such as the skin and mucous membrane that lines the nose, and an arterioveneous malformation if it involves larger blood vessels, as in the brain, lung, or liver.

Brain and pulmonary AVMs are often treated (with a 90% success rate) by performing an embolization procedure on the affected blood vessels. In 1978, White developed the technique of pulmonary AVM embolization along with Dr. Peter Terry at Johns Hopkins University. Much of White's global work began with his interest in Japanese embolization techniques.

Although nosebleed caused by telangiectasia in the nose (recurring in about 95% of patients) is the most common sign of HHT, an additional 25% of those with HHT will develop gastrointestinal bleeding, 30% will have one or more AVMs in the lungs, and 15% will develop brain AVMs, according to White.

Since every HHT patient has different organs involved, each is required to have a complete "fingerprint," or personal diagnosis to find out which organs are involved. Many patients are required to have an MRI to screen for brain AVM, in addition to some combination of contrast echocardiography, chest CT, or chest x-ray and arterial blood-gas determination to screen for pulmonary AVM.

Global HHT centers employ a multidisciplinary team of doctors and specialists in order to accommodate the condition's complexity. Centers generally include a genetics counselor, respirologist, gastroenterologist, otolaryngologist, neurologist, and cardiologist, as well as an interventional radiologist.

"HHT has got something for everybody," White said. "There are no turf issues with this disease."

Dr. Carlo Sabba, an associate professor of urgency medicine at University of Bari, Italy, and the director of Italy's only HHT center, describes the multidisciplinary approach to medicine as one that works in many applications and has been particularly successful in the Italian center.

"We have established an efficient and enthusiastic team of specialists who are extremely active in following the patients and in the research necessary to improve the situation of these patients," Sabba said. "The interdisciplinary approach has been very successful for us."

Besides the already established worldwide HHT centers, White hopes to help create additional centers in Argentina and Israel in the near future.

Dr. Meir Mei-Zahav, a pediatric pulmonology consultant in Kefar Saba and Tel Aviv University in Israel, has been instrumental in working toward the establishment of an HHT center in Israel.

"We all tend to look at everything from a certain perspective, underestimating the importance of other perspectives," Mei-Zahav said. "Many subjective opinions will sometimes give the most objective approach."

Medicine was and is still built on experience and on pure science - trials and collecting evidence for better care, Mei-Zahav said. Sharing the information always leads to better care for the patients.

That is the bottom line for White: better information, diagnosis, and treatment for the patient. Besides, he finds it a pleasure to travel and work with doctors in other countries.

"This is a great to do if you have time in your career - traveling to these countries, scrubbing up and doing some cases together," he said. "We have just as much to learn from them as they do from us."