Friday, December 3, 2010

11.5 FAQ5 - The Third I

CNN reports on 12/2/2010:

* A New York University Professor [Wafaa Bilal] installed a thumb-sized camera in back of his head for art exhibit
* Iraqi born photography professor had the procedure done at a piercing studio last month
* The camera will take a single snap-shot each minute of everyday activities for one year

This is an implanted mini-camera, no less. Incredibly, the procedure was done at a "piercing studio", an accident, in many forms, waiting to happen. It also begs the question: "why not a head-mounted camera":

Just point it the other way?

Tentative answer: An artist's mind works differently from yours and mine?

Thursday, October 28, 2010

11.4 FAQ4 - Gucci 3D glasses

It finally happened. Time Magazine reports today:

3-D technology just got a whole lot sexier.

"Gucci has stamped out its own corner in the tech market with a new line of luxury 3-D glasses. The 80s-style aviator plastic specs will retail for $225, and feature that coveted (for some) Gucci logo. Technically speaking, the glasses feature 6-base curved lenses that operate with circular polarized technology, allowing images to trick your eyes into seeing a 3-dimensional picture, and a mirrored coating to help with color contrast. (Most complaints with modern 3-D film conversion focus on how dark or dingy the picture appears.)"

Questions: (1) 6-base curved lenses? And (2) Circular polarized technology allowing images to trick your eyes into seeing a 3-dimensional picture?

Answers: (1) Optician lingo referring to the curvature of a lens with no refractive power (i.e., a plano lens, used in sunglasses). A 0=totally flat, an 8=very curved, and a 6=cool-looking curved lens. And (2) A better way than linear polarization of allowing each eye to see a different image, or together, a stereo pair. The stereo view is retained even if you tilt your head a little, hence more comfortable when watching 3D movies. However, it is the brain (in the intraparietal sulcus area), not the eyes, that is tricked into seeing 3D.

We have no comments on the US$225 a pair price tag.

Wednesday, October 13, 2010

11.3 FAQ3 - Sunglasses

CNN reports:

[Updated at 5:55 a.m. ET, 6:55 a.m. Chile time] Dawn is breaking in Copiapo, Chile and the miners will be facing a change in light as they emerge from the rescue chamber.
All of the miners now will likely be wearing sunglasses so they can adjust after being underground in darkness for more than two months.

So far, eight miners have been rescued, in a little under eight hours.

Our congratulations to the 33 miners for having survived 69 days underground and to the rescuers for accomplishing an almost impossible mission.

Q: Why the sunglasses?

A: Sunglasses are intended for protection from solar UV, both UV-A and UV-B. However, in the present case, they seem to be for acclimation to light from prolonged dark-adaptation. If so, then tinted goggles make more sense than sunglasses; the latter still allow lights from the sides. On the other hand, light-adaptation per se does not require much effort, the photo-receptors know what they are doing. Perhaps the purpose is simply for the miners to avoid photophobic irritation from sudden pupil constriction - again, a transient event - although it beats squinting into the sunlight/limelight.

In any case, it is apparent that a lot of thoughts have been put into preserving the well-being of the miners including their eyes. This deserves our appreciation and applause.

Monday, September 13, 2010

11.2 FAQ2 - gene of the week

The "gene of the week" phenomenon finally catches up with myopia. In headlines around the world today, news under the heading, e.g., "Genes for Myopia discovered" spreads like wildfire.

According to

"Researchers from the Department of Twin Research at King’s College London have identified genes associated with two common eye problems, myopia and glaucoma. The findings have been published in this week’s edition of Nature Genetics [see ‘A genome-wide association study for myopia and refractive error identifies a susceptibility locus at 15q25’. Pirro Hysi et al. Nature Genetics, 12 September 2010, doi:10.1038/ng.664]."

"In their study of over 4,000 twins, the researchers identified a myopia susceptibility gene called RASGRF1, which has been replicated in over 13,000 other people from the UK, the Netherlands and Australia."

According to Daily Mail, "Within just ten years, a drug that prevents short-sightedness or stops it in its tracks could be in widespread use."

However, "A second study, by Dutch researchers, identified a second short-sightedness gene. Ultimately, there could be dozens behind the condition."

There is more: "We hope that by understanding the mechanisms we can stop children from becoming shortsighted and stop short-sighted children from becoming more short-sighted."

Question: "Even though the mechanisms are still unknown, and yet, in 10 years, a drug can be developed to stop myopia?"

Answer: "Don't hold your breath."

Saturday, August 28, 2010

11.1 FAQ1 - cataracts

[Three major types of cataracts, cortical, nuclear, and subcapsular.
Occasionally, numerous vacuoles can be seen in the cortex that eventually evolve into opacities. In the image above, light comes in from the right. ]

Whenever a doctor informs an elderly patient of the presence of cataracts, the patient will inevitably asks "what do I do now?". His/her real question is "what can I do to reverse or remove the cataracts without surgery". And the honest answer is "nothing you can do". Since age-related cataracts are caused by cumulative events leading up to irreversible protein aggregation and disruption of cellular integrity, there is nothing in the form of eyedrops that can repair these damages.

What about preventing cataracts from further progression? Perhaps, if the current thinking of the causative factor of age-related cataracts, oxidative stress, holds up. Oxidative stress has been blamed for many human illnesses and is becoming a favorable catch phrase for the for-profit anti-aging industry. There is nothing wrong as far as oxidation and cataractogenesis. In fact, hydrogen peroxide in relatively high concentrations has been discovered in the aqueous humor of the human eye. And solar radiation of the lens, particularly that from the ultraviolet, starts soon after birth. Logically, anti-oxidants should then retard the progression of cataracts. The problem is: "which ones that work". This is where the unproven therapeutics with fraudulent claims come in. Any proof of efficacy must be based on large-scale clinical trials and yet, none have been done thus far. On the other hand, dietary intake balanced with natural food produce rich in anti-oxidants is not a bad idea. Stay out of the sun, if you remember to take your vitamin D or wear UVA and UVB-blocking sunglasses.

Surgery? Sure, when the decreasing visual acuity meets the screen guidelines. Cataract extraction is a low-risk highly effective procedure. However, the outcome will depend on (1) the skill and the experience of the surgeon; (2) the status of the macula/retina; (3) structural integrity of the eye globe; (4) underlying systemic diseases if any; (5) management of interim and final binocular vision; and (6) possible complications and treatments. A pre-op consultation with your trusted ophthalmic surgeon is of course indispensable.

Monday, August 9, 2010

10.16 Berklee adds a Braille beat

Boston Globe Aug 9, 2010:

Wayne Pearcy, a Berklee College of Music student, sits hunched before a console buried under a mountain of keyboards, wires, computer monitors, and microphones. A thin 23-year-old Louisianan with strawberry-blond hair, Pearcy is enthusiastically explaining his plan to write the next number one hit single.

[Complete article here.]

Monday, July 19, 2010

10.15 Who needs eyes anyway?

In the deep caves of Madagascar, absolute darkness led to the development of eye-less creatures, hence this:

Blind Shrimp Flee from Blind Cave Fish

Thursday, June 17, 2010

10.14 EYE in Chicago

EYE is a three-story tall eyeball sculpture that artist Tony Tasset will install in Chicago's Pritzker Park next month. You can see it, and it can see you, until the end of October. Some may find it creepy - Tasset acknowledged, calling it "surrealist-noir."

And the reason why it is a blue eye? Well, it is modeled after the artist's own eye. Is it anatomically correct? Most likely not. Would have been an educational opportunity if there is a door opening into a world of the intricate inner structure of the eye. One such model used to locate on the first floor of Singapore National Eye Centre. It may still be there. Check it out.

Wednesday, June 2, 2010

10.13 Bob Cousy on vision

Bob Cousy in his heyday, now 81

There is a fascinating comment by Bob Cousy that appears in Boston Globe [6/2/2010]:

“Vision, I think, for a point guard, is the most important thing. I was constantly being told I had eyes behind my head. It would seem that way to people who didn’t know that much about basketball who couldn’t believe that I could see things I could see. It’s exceptional peripheral vision.

“People who have tunnel vision don’t usually become point guards. That happened with [Chauncey] Billups here before they traded him. I think it was the only thing [Rick] Pitino ever asked me. I didn’t think Billups would make a good point guard because he would penetrate and then run into people. Billups proved me and Pitino both wrong, but I still don’t see him as a great creator in the vein of Rondo.’’

Rondo is of course the 6-1, 175-pound Celtic point guard Rajon Rondo. And here we go again: Game 1 of NBA Championship - June 3, 2010.

Beat LA!!

Saturday, April 24, 2010

10.12 Watch it at your own risk

3D TV has finally arrived. In an apparent attempt to ward off potential lawsuits, Samsung has publicized the dangers of 3D TV watching:

Photosensitive Seizure Warning and Other

CNN has an analysis: "Can 3-D movies, television make you sick?". In part, it says

[Samsung] cautions that certain flashing images or lights could induce epileptic seizure or stroke, and that "motion sickness, perceptual aftereffects, disorientation, eye strain and decreased postural stability" may result.

In addition: As for long-term effects of watching 3-D television instead of regular television, no one knows for sure because it's too new. concerned about serious consequences for children who watch 3-D television for long periods of time -- 'a continuous abnormal stimulus may possibly have long-term effects that are yet to be studied'...

So 3D TV watching can be hazardous to your health. Does it really? More research, please.

Wednesday, February 17, 2010

10.11 Avatar

According to China Daily [see here], a middle-aged female developed acute angle-closure glaucoma after attending a 3D showing of the movie Avatar. Presumably, pupil dilation induced by the dark environment for a lengthy period of time precipitated this attack. Curiously, however, the patient must have been staring at the bright movie screen; this, by itself, should have caused pupil constriction unless totally negated by the Polaroid glasses worn for the 3D effect. Unfortunately, no experimental data are available for a reasonable explanation.

Ultimately, the deciding factor is the structure of the angle in the eyes of each individual. A patient with extremely narrow angle will have a higher risk that often can be confirmed with the darkroom test. Intermittent narrow angle glaucoma cases can be examined with the darkroom prone-position test in which the patient stays for 45 min without going to sleep. And the IOP measured immediately after. An increase of 8 mm Hg is considered positive.

Not only the movies, 3D TVs are rapidly moving into the consumer products arena. The common complaint of asthenopia owing to the contraction of medial recti can be resolved with the incorporation of base-out prisms in the 3D glasses. Strangely, no manufacturers have bothered with this implementation thus far even though the cost is minimal.

A recent report of stroke/death of a hypertensive man in Taiwan [see here] after watching Avatar is most likely coincidental. It could have been from seeing any exciting movies, not necessarily the 3D effect per se; although medical issues do await further investigation.

All new technologies will have unintended side-effects, real or imagined, e.g., the much disputed correlation between cell phone use and brain tumor (there is none, BTW). The introduction of the pseudo-3D visual world to the populace is no exception. This may spur some much-needed research. Very simply put: who wouldn't want to enjoy 3D in both comfort and safety.

Sunday, January 17, 2010

10.10 Alzheimer's eye test


The headline of The Daily Mirror "High street eye test for Alzheimer's within five years" (Jan 14, 2010) is so tantalizing that prompts a further reading:

"A test for Alzheimer's could be carried out by shop opticians within five years. Scientists have found a way to detect the disease before any symptoms emerge during eye exams.

"By putting harmless fluorescent dye on the retina, they can spot dying cells - an early indication of Alzheimer's.

"The technique could end the need for costly MRI scans.

"Prof Francesca Coredeiro, of University College London, said: "Few people realise the retina is a direct, albeit thin, extension of the brain." and "It's entirely possible a visit to a high-street optician to check your eyesight in five years will also be a check on the state of your brain."

Wow, that is certainly progress; although a careful reading of the original research paper [here] raises some issues:

1. The high-street optician must own and be proficient in operating a confocal scanning laser ophthalmoscope to take the pictures of the retina through dilated pupils plus knowledge in interpreting the images;
2. To put the "harmless fluorescent dye on the retina" requires an intravenous injection of the dye, much like fluorescein angiography; the widely reported eye drops approach simply does not work; and
3. What evidence is there to support death and necrosis of the retinal photoreceptors in mice predates brain cell deaths, and even if true, does that apply to Alzheimer's in humans.

In five years? Maybe not.