Eye on Vision April 2015 Newsletter
In this issue:
Of the three main aspects of visual performance: VISUAL ACUITY, CONTRAST SENSITIVITY and VISUAL FIELD, Contrast Sensitivity is often the least understood. Precision Vision offers a variety of tests. Over the next several months Dr. August Colenbrander will answer some of your most frequently asked questions concerning contrast sensitivity.
Q: Can you tell me the difference between Contrast and Contrast Sensitivity?
A: Contrast describes a property of the object that is looked at. Contrast sensitivity describes a property of the eye that is looking. While the reflectivity of the various parts of the object, and hence their contrast, does not change when the illumination changes, the contrast sensitivity of the person does depend on illumination. Print with poor contrast that is not legible in poor light, may become legible when the illumination is increased.
That the human visual system spontaneously adapts to an enormous range of light levels, from a sunlit beach to a moonlit forest, which complicates measurements on an absolute scale. Most contrast tests are designed for an environment with good average illumination, but for persons with contrast problems changing the general illumination or providing task lighting may increase visibility. For some, like albinos, decreased illumination may increase visibility.
In next month’s issue of Ask Precision Vision Dr. Colenbrander answers your questions concerning Sine-Wave grating vs. Letter tests.
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Precision Vision ETDRS Cabinet Replacement Bulbs – Ask for them by Name!
Your Precision Vision ETDRS Cabinet and all its components, including bulbs, have been very specifically calibrated to suit your ETDRS testing needs.
We’d like to take this opportunity to caution you regarding substandard counterfeit bulbs and components. We have been made aware of bulbs very similar to those we provide that are marketed as suitable replacements for an ETDRS cabinet utilizing two bulbs. Be aware that bulbs from a source other than Precision Vision, Inc. are very likely not going to produce the proper light level or uniformity. When utilizing a Precision Vision Cabinet, please be sure to only use replacement parts and consumable products from Precision Vision, Inc.
When ordering replacement bulbs, please include your cabinet voltage, model number and Lot number found on your cabinet label near the on/off switch. See below for reference.
If you have concerns or questions regarding counterfeit bulbs or other components, please contact our office and we’d be happy to discuss this in further detail and make sure you get the proper products.
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The Industry Loses an Icon, Dr. Alfred A. Rosenbloom, OD, FAAO
On April 7, 2015 one of our industry’s most noted experts on Low Vision, Dr. Alfred Rosenbloom of the The Chicago Lighthouse passed away at the age of 94. A member of the National Optometry Hall of Fame, Dr. Rosenbloom was known for his visionary leadership and contributions in the field of optometric education with an emphasis in the area of Low Vision.
Dr. Rosenbloom is survived by his wife of 66 years, Sarah, two children Alfred the third and Susan and two Grandchildren, Aaron and Jessie . Dr. Tracy Matchinski, OD is quoted as saying, “His passing is a sad event, but it also allows reflection on his many accomplishments and contributions. Dr. Rosenbloom…a life well lived.”
Condolences should be sent to the Rosenbloom Residence: 910 N. Lake Shore Drive, #1819, Chicago, Illinois 60611 and Memorials to the: Alfred & Sarah Rosenbloom Center on Vision and Aging, Illinois College of Optometry, 3241 S. Michigan Ave, Chicago, Illinois 60611.
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Dr. Hoggat and the MacKinneys Return from Nepal!
Last month we sent out our well wishes to Dr. Judy Hoggatt of the Suson Eye Specialists, M.D. S.C. and Ted and Rachel MacKinney with TEAM | The Evangelical Alliance Mission who embarked on their journey March 12th, to the remote Sankhuwasabha district in Nepal just east of Mt. Everest to establish Mercy Clinic, a permanent medical clinic in the small village of Chepuwa.
This group returned to the United States from their mission. Upon their return Rachel dropped us a note to recap their trip.
My husband and I started working in Nepal in 1993. We raised our 3 kids here. Ted is a doctor and I am a nurse. We established our first hospital in the foothills of the Himalayan Mountains in 1994. For the last 3 years we have been making treks up the mountains, east of Mt. Everest, in preparation to establish Mercy Clinic. Just a few weeks ago, this clinic opened up.
Our friend, Dr. Judy Hoggatt, flew up in a helicopter and helped us the first week that the clinic opened. We want to thank you for your generous donation that Judy brought with her. Judy used the visual acuity charts while she was there and then taught our local health worker how to use them. Your donation will be used for many years.
Thank you so much!
Ted and Rachel MacKinney
Thank you Rachel! Precision Vision was happy to help you all in this worthy cause!
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