slitlamp fundus exam technique tips etc.

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persikov

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Hi all.

So, I'm 3 days into my ophtho residency. I haven't done much so far, basically the attending examines the patient, then it's my turn to repeat the procedure. For some reason none of the attendings seem to fancy the BIO, they just go for the slit lamp. As I'm having some doubts regarding my technique, I'd greatly appreciate if someone could give me some tips. The docs I'm working with have 15+ years of experience, and although they're very kind and helpful, they keep repeating the obvious - do it a few hundred times, and you'll get the hang of it. I appreciate the importance of experiance, but surely there must be some useful tricks to make slitlamp fundoscopy easier for a newbie 😀

1.) I'm only able to focus on the retina in dilated patients.

2.) If I manage to focus on the retina, which can easily take a minute or so, I only observe a narrow section of the retina, corresponding to the width of the light beam (yes, I'm aware of the fact it's logical, although I did expect the field of observation to be somewhat wider). The problem is, that if I then procede to examining the periphery by asking the patient to redirect his gaze, I'm basically lost as to how much of the fundus I've "lost" between the 2 directions of his gaze, ie. I'm afraid I'll miss some important finding. Am I being paranoid?

3.) Reflections are all over the place. Adjusting the angle of the (90D) lens by tilting it along it's horiz./vertic. axis makes no difference whatsoever; neither does adjustment of the illumination angle.

The only thing I've found helpful so far, is starting with a low mag. (6x), focusing on the fundus, then increasing to 10x and 16x. It works ok, but takes time, and for some reason at times I'm not able to focus at all, even though I follow the same procedure. Any advice is greatly appreciated. 🙂

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When I was starting my first rotation in ophtho the fellow told me you just need to practice when I asked how to do the 90D exam. That really pissed me off, but now that I've have a few months under my belt, I've realized what he said is totally true. You just need to keep screwing around with it patient after patient and you just somehow get better. The one piece of advice for the undilate patient is to line everything up. Put the beam through the pupil then put the lens up right in the middle and don't move the slit lamp laterally. I usually can find it if I get the aligment straight. As frustrating as it is, it really is practice makes perfect. Good luck
 
Lining up is crucial.. not only to get a good view but also to get stereoscopic view. Once you're lined up, it's much easier to pan around and also to reduce any reflections that you might have. Way to practice lining up is to practice taking turns closing each eye and make sure you still see the fundus. If you lose the fundus, you're not lined up. Another way to help practicing lining up is try it with a 78D lens. It's easier to line up grossly.. and once you get good with that, move to a 90D. personally, i like the 78D better, butfor small pupils, you'll need the 90D.
 
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Thanks to both of you for your replies. Well, I guess practice is a key-word. I'm doing much better already, able to focus without problems with a higher mag straigh away, and the reflections don't seem too bothersome if the pupil is nicely dilated.

Thanks for Your assistance.
 
One additional pearl. I found using a filter is much better then full brightness. It helped me view the macula much better. The exception is when you have to see through a well developed cataract.
 
if you turn down the intensity of your slit beam (almost to the lowest setting if you have a rheostat) you can widen the beam to ~disc diameter to see a bit more without making the patient pass out from the intensity of the light
 
@EYESURG and ryangeraets: I discovered the beam intensity regulator only recently by... accidently burning the bulb, lol.

How much training did you guys get before going on-call?
 
we had about a month of urgent care before going on call, but it was still a bit scary being on for the first time knowing that my exam skills were sub-par at best...but that's why there is backup from the upper level residents and even the staff on call.
 
We had 3 weeks of "puppy" call--tagging along the seniors. We went solo afterwards with seniors as a back-up.
 
one other thing not mentioned, the 90D lens needs to be held a bit closer to the eye than a 78D, and a 66D held the furthest away. Technically, you are supposed to have the illumination at a slight angle to remove some of the reflections, but that doesn't always work in reality.

one silly thing, patients not holding their head on the chin rest and up against the forehead rest make it very difficult early on. Some patients tend to back away after a short time and if you don't move back and notice you can end up searching and getting frustrated easily....

just trying to remember some things from back in school. been a while.

the type of slit lamp can make a big difference, but you'll just learn on whatever you have available.

good luck.
 
I used this tutorial to learn on the 78.
The 90 is more difficult, and yes, it needs to be just about touching the eyelashes.
When first learning, I found it easier to use the pull all the way back and then slowly move forward technique. Because you continuously see the inverted image of the eye, you can maintain alignment, until you hit the macula, then the macula just springs into view.

http://www.academy.org.uk/tutorials/volklens.htm
 
Reflection glare is a big problem, and can be minimized by keeping the optical path (bio/lamp, cornea/pupil, viewing lens) in perfect allignment. Practice makes perfect.

However, there is another trick that may help. You can insert a polarizing filter (circular polarizer works best) into the light path. This cuts down on reflective glare (it also reduces light transmission a bit, but the trade-ff is worth it). This trick is not well-known, but it does work.

Nick
 
Thanks to all for the advices given.
 
Reviving this baby...

So, I'm one month into my residency and slowly things are getting better with the BIO and anterior segment, but I still feel there's some trial and error for me with the posterior segment SLE.

Here are some specifics...

I line things up. Generally I use a 78 and if not dilated I use a 90. When I line things up, I either see a reddish background (almost like when I first look at the red reflex w just the beam and no lens in front) through my lens or black background through my lens. When I see the black background I usually get to the red reflex/retina image easier. What am I doing differently between the two background appearances? I'm guessing it's my lens tilt or something.

What color background/light should I see first when lining up before I begin to pull back?

Im frustrated because sometimes things pop into view perfectly and other times they don't. I know it takes practice but I WISH I understood what adjustments could make it better...
 
Easiest way I found when I was starting was to:

1) First focus the SL on the iris at the centre of the pupil
2) Look around the SL and align the Volk lens so that it's perfectly straight and the light passes straight through to the patient's pupil
3) Look through the eyepieces and pull the SL all the way back.
4) Move the Volk lens back and forth as well as up and down so the pupil and iris come into focus
5) Move the SL forward and the Volk lens forward (at about 1/10 the rate you move the SL)
6) You should hit the fundus now - move the SL laterally to try and find the disc (using just fine movements from the joystick)

After I did the above 20 or 30 times on undilated pupils (practice on your friends/ colleagues), I had no problem just telling the patient to look past my ear, holding the lens up and then pulling the SL back to get a view of the fundus.

If you're not tall rest your elbow on the Volk case. The steadier the hand you have, the better (but you'll be a surgeon so you should have no worries there).

Also for some reason, I find holding the lens so my fingertips are at the very edge of the flange helps (almost to the point where if feels like it might pop out of your grasp).

I learned all of this on a digital wide field so your mileage may vary.
 
practice is really the key.
my tips.
1. make sure patient is confortable and cathus is in line with the black mark and foreheard touching the plastic band.
2. be efficient. patients will get tired and start to slouch. that is why number 1 is important. make sure chair/table adjusted so patient is comfortable.
3. focus at iris plane with a good red reflex, place the the lens in front of the eye (you start to know how far away from the eye it should be with practice), then slowly pull back and get the virtual view of the retina in focus.
 
Most everyone has been recommending aligning the slit beam and bio to minimize glare. I used to do this but found a little trick that really helps to keep glare down. I turn the bio and slit beam both about 10 degrees off center (say slightly to my left for the patients right eye and slightly right for the patients left eye). I then line up the pupil and my lens to get a red reflex then pull back to focus on the retina. I turn the light down a bit as well. I then turn light up as needed though you would be surprised how little light you need to visualize what you need and not make the patient miserable. It's a fine balancing act. I avoid filters if I can as I feel this does degrade the image a bit. Most slit lamps allow you to control the intensity of the light and I rather control that. Also, a thinner beam is better than an ultra wide beam to minimize glare. Lastly, you don't need a lot of magnification. Don't want to miss the forest for the trees. I rarely go to max magnification, but I use a 78D which I think provides excellent mag for most macula exams. Perhaps with a 90D I might use a bit more mag or with a macula lens to perform focal etc.
 
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