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Cone dystrophy

A cone dystrophy is an inherited ocular disorder characterized by the loss of cone cells, the photoreceptors responsible from both central and color vision. more...

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The most common symptoms of cone dystrophy are vision loss (age of onset ranging from the late teens to the sixties), sensitivity to bright lights, and poor color vision. Therefore, patients see better at dusk and have progressive difficulty with daytime vision. Visual acuity usually deteriorates gradually, but it can deteriorate rapidly to 20/200; later, in more severe cases, it drops to counting fingers vision. Color vision testing using color test plates (HRR series) reveals many errors on both red-green and blue-yellow plates.

The pathogenesis of cone dystrophy has yet to be elucidated. It appears that the dystrophy is primary, since subjective and objective abnormalities of cone function are found before ophthalmoscopic changes can be seen. However, the retinal pigment epithelium (RPE) rapidly becomes involved, leading to a retinal dystrophy primarily involving the macula. The histological examination of the eyes of one such patient showed that the outer nuclear layer of cones and rods had disappeared completely, whereas the RPE showed pronounced pigment changes. There was also atrophy of the temporal disc.

The fundus exam via ophthalmoscope is essentially normal early on in cone dystrophy, and definite macular changes usually occur well after visual loss. Fluorescein angiography (FA) is a useful adjunct in the workup of someone suspected to have cone dystrophy, as it may detect early changes in the retina that are too subtle to be seen by ophthalmoscope. For example, FA may reveal areas of hyperfluorescence, indicating that the RPE has lost some of its integrity, allowing the underlying fluorescence from the choroid to be more visible. These early changes are usually not detected during the ophthalmoscopic exam.

The most common type of macular lesion seen during ophthalmoscopic examination has a bull’s-eye appearance and consists of a doughnut-like zone of atrophic pigment epithelium surrounding a central darker area. In another, less frequent form of cone dystrophy there is rather diffuse atrophy of the posterior pole with spotty pigment clumping in the macular area. Rarely, atrophy of the choriocapillaris and larger choroidal vessels is seen in patients at an early stage. The inclusion of fluorescein angiography in the workup of these patients is important since it can help detect many of these characteristic ophthalmoscopic features. In addition to the retinal findings, temporal pallor of the optic disc is commonly observed.

As expected, visual field testing in cone dystrophy usually reveals a central scotoma. In cases with the typical bull’s-eye appearance, there is often relative central sparing.

Because of the wide spectrum of fundus changes and the difficulty in making the diagnosis in the early stages, electroretinography (ERG) remains the best test for making the diagnosis. Abnormal cone function on the ERG is indicated by a reduced single-flash and flicker response when the test is carried out in a well-lit room (photopic ERG). The relative sparing of rod function in cone dystrophy is evidenced by a normal scotopic ERG, i.e. when the test is carried out in the dark. In more severe or longer standing cases, the dystrophy involves a greater proportion of rods with resultant subnormal scotopic records. Since cone dystrophy is hereditary and can be asymptomatic early on in the disease process, ERG is an invaluable tool in the early diagnosis of patients with positive family histories.

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The sad allure of cancer quackery
From FDA Consumer, 5/1/85 by Richard Thompson

Had you called a certain 800 number a few months ago and said you were looking for treatment for cancer, you would have found yourself talking to a woman in Salt Lake City. She would have made travel arrangements and an appointment for you at one of several "cancer clinics," in particular the Universal Health Center in Matamoros, Mexico, just across the bridge from Brownsville, Texas.

The woman is no longer taking calls. She and her husband were indicted for interstate wire fraud, pleaded guilty in March 1985 to a lesser offense, and now await sentencing. Both have been arrested by Texas authorities and face state charges. A dozen other persons with ties to the center were indicted on medical fraud and drug charges. They also pleaded guilty or were found guilty at the March trials and await sentencing. The clinic itself has been closed by Mexican officials and its operator, James Gordon Keller, and his brother Ronald are wanted by the FBI on a fugitive warrant and are thought to be in Tijuana, Mexico.

Keller is a former water-softener salesman who, with a chiropractor-nutritionist, had earlier set up a similar clinic in Baton Rouge, La. When that was closed down by the Food and Drug Administration and state authorities in 1983, Keller and his associates made Brownsville their base and located the new clinic just across the Rio Grande in Matamoros. They assembled a staff of "therapists" and hired a Mexican doctor--who turned out to be unlicensed--and began advertising their services and their 800 number.

Their brochure was not modest in its claims. The center, it said, offered "an effective therapeutic approach to treatment of cancer and other diseases, including multiple sclerosis, lupus erythematosis, Parkinson's, muscular dystrophy, rheumatoid arthritis, cardiovascular and other degenerative diseases," with cancer control their specialty.

For cancer therapy, Keller was using virtually all the popular but unproved remedies. His brochure listed "tumorex and other support modalities, including DMSO, live cell therapy, Gerovital, enzyme therapy, cardiovascular chelation, nutritional education, colonic irrigation, reflexology, iridology, and deep nerve, deep tissue, lymphatic and Shiatzu massage therapies."

Keller bought 10 condominiums when he arrived in Brownsville, using one and renting the others to patients whose course of treatment would run about two weeks and cost some $3,000. The operation grossed over $100,000 a month.

Patients came from throughout the United States, with 20 or more in the reception room at a given time. Many were elderly and in the late stage of terminal cancer. If they appeared too near death, Keller might tell them they were anemic and needed a blood transfusion, which he could not give because, he said, "the medical establishment has a monopoly on blood." He would then refer them to a Brownsville physician, who began to find these confused people in his waiting room. The physician could not be a party to what Keller was doing; these people did not need transfusions; they were dying of their disease. The physician's encounters with these patients became part of the case that was developed against Keller.

Some patients coming to the clinic were not actually ill but had convinced themselves they were and were fearful of doctors. Keller would then diagnose a condition they did not have and "cure" them of it. Some, however, were truly ill and could have been helped with conventional medicine. Among these was a child with leukemia--a very treatable condition today--whose parents refused an offer by a pediatrician to send the child, at the doctor's expense, to a hospital specializing in that disease. Instead, they took heraway from this doctor's care and over to Keller's clinic. The outcome of her illness is unknown.

All of this may have been too much for Keller's chiropractor-nutritionist partner, Barbara Masse. Police records show that she attempted suicide in her motel in Brownsville. She survived, however, and is among those to be sentenced from the March 1985 trials.

At some point earlier in his career, Keller, the chiropractor and a third person operated in Oklahoma as a sales team offering a small, cone-shaped device that they claimed would diagnose and treat cancer. According to the sheriff in Idabelle, two of the team would go door to door and, if residents did not wish to buy the $70 device (or a deluxe model that went for $3,000), Keller would shortly appear with a pistol tucked in his waistband and try to persuade them they really wanted it after all.

Among those indicted was Keller's brother, a medical device salesman who had set up the Matamoros clinic by installing diagnostic and therapeutic equipment that was nothing more than dials, switches and colored lights. The equipment supposedly indicated the kind of cancer a patient had and the treatment that was needed.

The clinic staff also diagnosed disease by studying full-length photographs of patients and by swinging a pendulum over various foods in the presence of the patient. Foods over which the pendulum stopped were the ones the patient should be eating.

Federal and state officials, aided by FDA's resident investigator in Brownsville, built the case against the clinic. They were helped by the Brownsville Herald newspaper, which was doing its own investigation. To close the case, an FBI agent and a member of the Texas attorney general's staff posed as husband and wife seeking cancer treatment for their son. Keller said he could cure the child--who did not exist--for $3,000, paid in advance. This claim of being able to cure cancer triggered a court injunction, closing of the clinic by the Mexican government, seizure of drugs and equipment kept at the condominiums, and indictment and arrest of the clinic operators and staff.

Many of Keller's patients are unwilling to discuss their experiences, some because they continue to believe in him, others because they may be afraid. He reportedly walked about the clinic with a pistol stuck in his belt, and signs at his earlier clinic in Baton Rouge announced, "All the staff in this place are armed."

Keller's clinic in Matamoros operated far outside the legitimate practice of medicine, promising cures for cancer and other illnesses that would be laughable if they were not so dangerous. It used fear and intimidation to attract patients who were often near death from their disease.

Keller's clinic is an extreme example, but unfortunately it represents of only one small part of a much larger market for unorthodox treatments being promoted for cancer and other serious diseases. Many of these treatments have elaborate--but unproved--theories as to the cause of human illnesses and how they can be cured. And despite real advances in conventional medicine and technology, a researcher in Pennsylvania believes that more and more people are being attracted to unscientific, unproven, and often dangerous therapies.

That researcher, Dr. Barrie Cassileth of the University of Pennsylvania Cancer Center, set out to determine who seeks such treatments, how and by whom they are rendered, and why they are becoming more accepted. The findings were reported in the June 1984 Annals of Internal Medicine.

The study showed that persons receiving unorthodox therapy were not necessarily poorly educated, desperate, even dying patients who had exhausted all methods of conventional care. Instead, most were people who felt--rightly or wrongly--that they were taking a broad view of their own health and their responsibility for it. They were deliberately moving away from conventional medicine into programs of their own choosing.

Most were attracted to these unorthodox therapies because they believed the treatments were "natural and nontoxic" and would control their cancer. They seemed untroubled that the treatments have no basis in science. Forty percent had used but then abandoned conventional care; almost 10 percent had never tried conventional care. and about half of those receiving proved conventional treatment were also using some form of unorthodox therapy, such as extremely large doses of vitamins.

The unorthodox practitioners also did not fit the expected portrait of quack and charlatan. Many were well-trained (over half of them medical doctors), not all charged high fees, and most seemed to believe in the rationale and effectiveness of their work.

The Pennsylvania researchers identified six major types of unorthodox treatments among the patients studied. These were, in descending order of use, metabolic therapy, diet therapies, megavitamins, mental imagery, spiritual or faith healing, and immune therapy.

Metabolic therapy assumes that waste materials in the patient's body interfere with metabolism and healing and that the body's cells lack the nutrients essential to health. Cancer and other chronic illnesses are thought to be caused by degeneration of the liver and pancreas and of the immune and what metabolic therapists call the "oxygenation" systems. Treatment includes "detoxification," typically through "colonic cleansing" (enemas); special diets; vitamins and minerals; enzymes; and occasionally Laetrile, an unapproved and toxic substance made from apricot pits. Most of the patients using metabolic therapy received it from medical doctors and were treated in the United States.

The second most used treatment--diet therapy--consists of eating specified foods prepared and consumed in a specified way. A "macrobiotic" diet of whole grains and soybeans with purported anticancer properties was most popular. The diet is based on the Far Eastern concept of natural balance (yang and yin) and the belief that body cells, organs and tissue originate in a "mother red blood cell" in the intestine, hence the need for a careful diet.

Use of megavitamins was the third most popular therapy. It involves taking one or several vitamins in extremely large doses in the belief that this will strengthen the body's ability to destroy malignant cells.

Mental imagery as a cancer therapy requires patients to visualize the destruction of cancer cells in the body, thereby reversing the malignant process. Faith or spiritual healing involves the use of prayer, laying-on of hands, and other actions, without the help of conventional medicine, to cure the cancer through divine intervention or to exorcise the evil that is believed to be the disease.

Immune therapy here refers to injections of interferon, animal fetal tissue, autogenous vaccines (made from the patient's own body fluids), and other agents. The claim is that cancer develops because of defective immune mechanisms and that this treatment strengthens those systems. (Immune therapy on a more scientific basis is used in clinical trials and conventional medical settings.)

In addition to these six most popular unorthodox therapies, over 40 other treatments and their variants were used by one or more of the patients interviewed. They included botanical (plant-derived) treatments, often based on folklore; colonic cleansing and eating raw foods to overcome intestinal poisons; and detoxification, often with coffee enemas to stimulate bile production and eliminate "intestinal poisons."

Unorthodox therapies are attractive because they offer explanations of disease that are simple and persuasive, even though they have no basis in science. The treatment itself, though not proved effective, is more pleasant and comfortable than, say, chemotherapy. Since patients increasingly want to share in the responsibility for their own health, the emphasis on prevention attracts already healthy individuals who welcome the implied promise of continued good health.

Although the Pennsylvania study was done with cancer patients, it may apply to other conditions as well. One difference between past and present unorthodox therapies is that today's are not always directed toward a particular disease. Instead they are usually based on a prescribed lifestyle and promoted for the prevention, treatment and cure of most chronic diseases. This, says Dr. Cassileth, has serious implications for conventional medicine, as patients abandon treatment that is known to be effective for the often dangerous promises of unproven unorthodox therapies.

COPYRIGHT 1985 U.S. Government Printing Office
COPYRIGHT 2004 Gale Group

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