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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 "expert beginner." - Victoria Bondoc's Gemini Industries Inc - Company Profile
From Nation's Business, 1/1/95 by Harriet Webster

Apparently nothing could stop Victoria R. Bondoc from starting--and succeeding at--a business.

Bondoc was 26 when, in 1986, using $1,500 in personal savings, she founded Gemini Industries, Inc. Today her company, a full-service information systems and facilities management firm based in Burlington, Mass., employs 110 people and operates out of six offices in Massachusetts, New York, Virginia, and the Philippines. Nearly 95 percent of the company's work is in the form of government contracts, many with branches of the military. Revenues for 1994 are expected to reach $5 million.

Bondoc, the daughter of Philippine immigrants, is legally blind. When she reads, the page nearly touches her face. But she has never let her lifelong vision impairment--called cone dystrophy--deter her. When she went job hunting after earning degrees in mathematics and computer science from MIT and Boston University, respectively, she didn't mention her disability to potential employers. She worked for two major consulting firms; both assigned her to military projects.

Put off by the bureaucracy inherent in huge companies and frustrated by the difficulty of commuting several hours a day by public transportation--her poor eyesight makes driving impossible--Bondoc decided to start her own company.

Through the network of contacts she had established at the consulting firms, she won her first contract--setting up a computer system to help the Navy evaluate proposals it received from different types of companies. "It was a very small job," Bondoc says. But she impressed her client by offering to set up an office near its site in Maine for six months to provide the necessary support. "A bigger company probably wouldn't have been willing to do that," she says.

At first, Bondoc's potential military customers were reluctant to contract with a firm headed by a young woman who had never been in the military. "What they would typically do," she recalls, "is say, 'Why don't you team up with this big company, in whom we have a lot of confidence?' So they would give us a small part of a larger job." As Gemini developed a success record, customers gave it a bigger slice of the pie.

Bondoc met her biggest challenge in 1991 when a major contract was awarded to a competing firm. She heard rumors that the client's senior staff preferred not to deal with a company headed by an outsider--a minority woman with a physical handicap and no military background. Morale at Gemini plummeted. Several key staff members left to join other firms. Annual revenues fell 33 percent in 1992.

Bondoc confronted the crisis by meeting intensively with her management team and with customers to pinpoint what led Gemini both to its successes and to its present difficulties. The key to Gemini's eventual revitalization, she found, was to capitalize on--not minimize--the qualities that set her apart. "Ultimately," she says, "the value of what our organization brings to customers stems from the fact that I never was an insider." To recast Gemini's image, Bondoc began to market her company as the "expert beginner."

"The strength of the 'expert beginner' is that we're not predisposed to the traditional ways of solving problems. We come into the situation with a fresh perspective," says Bondoc.

The company has since won contracts with the Department of Transportation, the Air Force, Unisys Corp., Digital Equipment Corp., and even a promoter staging performances by Prince.

Earlier in 1994, Gemini was named a state honoree in the Blue Chip Enterprise Initiative. The program, sponsored by Nation's Business, the Connecticut Mutual Life Insurance Co., and the U.S. Chamber of Commerce, recognizes businesses that have overcome adversity.

Gemini emphasizes its ability to design technology to meet a customer's distinct needs. That's what it did at Hanscom Air Force Base in Massachusetts, where the staff was responsible for building major command-and-control systems. There, Bondoc says, Gemini developed a program "to keep track of their ongoing tasks--who was developing software, who was reviewing data, whether tasks were being accomplished on time, and so forth."

In a world characterized by rapidly developing technology, Bondoc believes the success of an organization will be determined by its attitude toward change. Gemini, she says, helps its clients "attempt to maximize their ability to initiate change, adapt to change, use change to their advantage, and work within the continuing chaos that characterizes the world."

COPYRIGHT 1995 U.S. Chamber of Commerce
COPYRIGHT 2004 Gale Group

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