At Press Time

Vision Loss After Non-Ocular Surgery

This Complication Has Increased in Recent Years.

By Jerry Helzner, Senior Editor

■ Almost every ophthalmologist has had the experience of a patient complaining of significant vision loss after undergoing cardiac bypass or other non-ocular surgery. Unfortunately, ophthalmologists are relatively powerless to deal with postoperative visual loss (POVL) because the damage is usually caused by an ischemic or other event that occurs during surgery and is irreversible.

Reports of POVL have become more numerous in recent years, correlating strongly with the increase in coronary bypass procedures. However, other non-ocular surgeries can also lead to POVL. Though many cases of POVL are never reported, a recent article by Molly E. Gilbert, M.D., of the Department of Neuro-Ophthalmology, University of Illinois Eye and Ear Infirmary, notes that it has been estimated that this complication is occurring in as many as 4.5% of cardiac surgeries.

Dr. Gilbert's article, which appeared in the journal Neuro-Ophthalmology, identifies a variety of factors that are believed to contribute to POVL. Some of these risks are intrinsic to the individual patient, such as diabetes, hypertension, age, vascular disease, history of smoking, optic nerve head morphology and variable optic nerve blood supply. Other risk factors are related to the surgical procedure, such as prone positioning, extraocular pressure, increased venous pressure, prolonged surgical time and hypotension.

"A variety of factors make POVL difficult to predict and prevent," writes Dr. Gilbert. "Many patients have certain clinical factors that could predispose them to developing POVL. In addition, many surgeries use deliberate hypotension, prone positioning, long surgical times or are associated with acute blood loss without leading to POVL."

Dr. Gilbert writes that direct pressure on the eye has long been associated with POVL.

"It has been noted numerous times in the medical literature and is associated with extraocular pressure leading to decreased blood flow to the central retinal artery. It is the most important cause of POVL medicolegally because it is avoidable."

Dr. Gilbert concludes that education of anesthesiologists and (non-ocular) surgeons is paramount in the prevention of POVL. Among the precautions these practitioners should take is obtaining a complete preoperative history to identify any preexisting patient risk factors that predispose to POVL, evaluating the use of deliberate hypotension in patients at risk, avoidance of compression of the eye, abdomen or chest in patients placed prone, and correction of anemia and/or hypotension as early as feasible upon identification of these risk factors.

A Mission Links Family to Its History

Dr. Conrad Brings Eye Care to Rural China.

It's no accident that William C. Conrad, M.D., of Warner Robins, Ga., is the founder of one of the few American-based eye care efforts serving China. Since 1993, Dr. Conrad has returned each summer to rural and rugged Gansu Province in northwest China, primarily to remove vision-robbing white-pupil cataracts that are prevalent in this poor and mountainous area of the country.

In all, Dr. Conrad has made 25 trips to China, while his wife Peggy has made 23 of them.

However, Dr. Conrad's link to Gansu Province actually goes back to the late 19th century when his grandparents spent 32 years as missionaries in that area.

"My mother spent her first 8 years in Gansu Province," Dr. Conrad says. "I took my family on a heritage trip to Gansu in 1987 and one of the first things I noticed was the great need for eye care. In the rural areas, many of the people had white cataracts."

It took 5 years to negotiate a contract with the provincial government to obtain permission to perform ophthalmic procedures. "We created an organization called GANSU, INC (Gaining A New Sight for Unseeing in China), and developed a proposed contract," recalls Dr. Conrad. "We negotiated for 10 days with the provincial health bureau and created a good working relationship that spelled out each party's responsibilities."

Dr. Conrad's strategy was to outfit a pop-up camping trailer as a mobile surgical cataract suite and bring eye care to the rural people who could not travel to a central location. The provincial health bureau does the initial screening of patients and provides the visiting surgical team with a list of patients to treat.

"This concept has worked out very well for us," Dr. Conrad notes. "Most of the patients need cataract surgery, but we can treat pterygium, perform iridotomies and do basic glaucoma surgery. We also have a YAG laser. At the end of the summer, we pack up the equipment, and the trailer, putting all in storage until we return the next year."

Dr. Conrad in China with a delighted cataract patient. Photo courtesy of GANSU, INC.

As the years passed, GANSU, INC has attracted an increasing number of supporters, including many Chinese-Americans. It takes more than $200,000 a year to fund the humanitarian effort. Companies such as Alcon, Abbott Medical Optics and Becton Dickinson have been exceptionally generous with supplies and IOLs.

"This summer, we expect to bring eight surgical teams, each with five people, for 4-week rotations," says Conrad. "Four of the teams will go to Gansu and four to neighboring Qinghai Province." One of the goals of GANSU, INC is to train local ophthalmologists so they can perform the extracapsular cataract procedure that the organization uses (more than 5,200 cataracts since 1993).

"We have also initiated 2-week training seminars in the provincial capital of Lanzhou," says Conrad. "We bring subspecialists in retina, pediatrics, glaucoma, phaco and oculoplastics. The seminars attract 80 to 100 local doctors who benefit from the interaction with these experts." These efforts have earned GANSU, INC the highest awards that Gansu Province, and the Central Government (The China Friendship Award) can bestow on foreigners.

Dr. Conrad, who is now 73, and retired from active practice, says there have only been two glitches in the many years that GANSU, INC has been operating in China. "In 2003, we had to shorten the mission because of the SARS epidemic and last year we had to wait until the Olympics were over because the Chinese government was concerned about the Tibetan protests. But overall, our relationships with the Chinese provincial and central governments have gone very smoothly."

Anyone interested in getting involved with GANSU, INC can go to the organization's Web site at www.gansuinc.org