Thursday, November 11, 2010

Doctors Appointments and Laser Safety

Yesterday was a long day of doctors appointments for me.  Since I was preoccupied much of this summer with my kidney stone, a few of my maintenance doctors visits got pushed to the back burner.

Appointment #1 - Family Medicine

My first appointment of the day started at the family doctor where both my husband and I had appointments (we try to sync appointments like this together since we only have one car and work far away from our doctors).  I was there for blood work and to have my new doctor work with me to get me off some of the many prescriptions my old doctor had me on (this is one of the reasons I changed doctors).  Everything is looking good there and I am pleased with the plan we are working on.

Appointment #2 - Dentist

I had an appointment with my dentist about a month and a half ago to have a filling fixed.  I was in the chair and all of the odds and ends and drill bits were set out when I mentioned to my dentist that, from time to time, I get a slight twitch under my right eye.  It was happening right then and he declared that he wouldn't touch me until I get confirmation from my neurologist that this dental work would not make it worse (he was worried that the anesthetic he intended to use would effect the same nerve he believed to be causing the twitch).  I told him that this is related to my TMJ and if I relax my jaw, it goes away.  He was still uncomfortable and sent me home.

So, with a note from my neurologist in hand, I returned and finally had this taken care of.

Appointment #3 - Eye Doctor

It has been a little over a year since I blew a blood vessel behind my retina and since I wore my contacts (the eye drops they had me used could not be used with contacts).  Now that my retina in better, I needed to see the eye doctor again to have my prescription renewed so I can order new contacts!  To my surprise, my prescription hasn't changed at all!  Yea!

My visit to my eye doctor reminded me of why I go to this particular doctor.  And the story starts the laser safety at LIGO...

Laser Safety at LIGO

When a new employee, student or visitor starts working at one of the LIGO observatories, they must undergo laser safety training especially if they will be working directly with the lasers or if they will be working around the lasers.

The laser used in the last data run here at LIGO was a 35 Watt Nd:YAG laser.  The first thing that makes this laser particularly dangerous is that it is powerful.  35 Watts is the equivalent of shining 35,000 of the common red laser pointers on the same spot (so that the dot is no bigger than if you were only using one laser).  That is plenty powerful enough to burn a hole in your retina and this is an injury that will NEVER heal.  If you are lucky you will simply have a blind spot in your peripheral vision and if you are unlucky you will be permanently blinded.  The other aspect that makes this laser dangerous is that is a wavelength (color) that you can't see.  The laser produces 1064 nm (about 0.0000419 in) wavelength light which is infrared.  Since we can't see the laser at all, it can be especially difficult to avoid it.  If even the reflection of this light (that you cannot see) enters your eye, you will have a burned retina.

For these and other reasons, everyone who will work with or around the lasers must undergo laser safety training, have their eyes examined, their retina photographed and wear laser safety goggles when around the detector.  That is how I came to see my eye doctor here in Baton Rouge for the first time.  This will also not be the last time I see this doctor...  Any time a that there is a suspected laser injury to the eye, that person is sent back to the eye doctor for the whole exam again.  They then compare the how the retina looks now to how it looked before the person started working around lasers (that's why they took the first retina picture) to determine what, if any, damage was done.  Also, when someone no longer works at LIGO, they must go for an exit exam to make sure that there was no damage done that they were unaware of.

I don't have any recent pictures of me in the awful green laser safety glasses, but I do have an old one from the first time I got to take a tour of the inner workings of LIGO.  Below, is a picture of me [right] when I was a graduate student and a very good friend (and fellow graduate student) Tiffany Summerscales [left] by one of the vacuum chambers inside the LIGO Hanford Observatory (the sister observatory in Washington state to the Louisiana one).  This picture is from August 2004: