The first experience of using a direct fundoscope is tedious but if successful, it's rewarding.Because apart from the importance of clinical signs in retina/fundus, we find that retina is an elegant tissue. Behind the lens there is big world of vessels, and a world of clinical signs. No doubt eye is a window to brain, but to see through this window, we need a good practice with the use of direct opthalmoscope, and patience if our patient is non-cooperative(specially kids). Indirect opthalmoscopy may be easier. However, the instrument for (bedside) fundoscopy is quite complex in its optics, and needs good expertise to use it rapidly to see retina.
During my house job rotation in East Medical Ward, Mayo Hospital,Lhe, my seniors introduced me to this instrument, direct opthalmoscope. The model they carried back then was the same one as in photograph above.
With simple instructions given by them, after an effort of 2 minutes , i was able to see just a glimpse of vessels in retina. It was all very beautiful. But i could not locate fundus or track vessels.
Very few doctors carried the instrument with them as it was ëxpensive. And so, everyone relied on eye department for trivial retinal findings.
The physics that is involved in opthalmoscope is a really simple one. I illustrate it here as :
The rays of light from bulb(a) get collimated(parallel) by lens(b) , mirror(c) deflects them 90 degrees towards patient's eye which then go through patient's pupil>lens>strike retina > return from retina>lens>pupil and come back just near to mirror of ophtalmoscope, and physician sees those light rays through aperture(g).
From this physics, i ascertained the issue, an issue that"direct opthalmoscopy is hard to learn ,and not everyone can do it in the first go".
I guessed that the distance "i" is making the job tedious.
The second issue , "expensive" instrument, was because of the optics used in the instrument.
To eliminate all optics, i came up with an idea, to use Surface Mount Device type Light Emitting Diode as a light source, on a piece of card or preferably Printed Circuit Board, and make an aperture in it so that the distance "i"is considerably reduced.
I also found out that , if SMD LED is placed close to cell phone camera , very close , then cellphone camera works like a fundoscope. If you understand photography, then you know that FLASH is placed a bit far from Camera so that RED EYE REFLEX is minimized. I brought LED closer to camera, to make RED REFLEX more pronounced , and once very close to eye, to see through eye.
Follow below.
The above two diagrams illustrate well the idea. Distance "i"is considerably reduced.
The initial version made according to the plan looked very much like this :
This device was named as OptiCard, it had an aperture in its upper piece for direct fundoscopy (without cell phone camera), and the device could be attached to cellphone camera by folding the upper piece of card, as below :
The image of retina visualized using cellphone :
By reducing the distance "i", everyone can do fundoscopy in the first go.
More research data is needed however, to prove my point.
(I have shared the link to my research paper below).
So the instrument as per end of year 2017 , looked very much similar to the one in above photos.
It had two pieces.
In 2018,
I came up with another idea, to make aperture in the card below LED.
I used printed circuit board, and SMD switch and the final device looks like :
Front
Back
Attached to cellphone Camera
The video demonstration of the gadget is as :
With the intent to create a less expensive device I found an easier way too , to visualize retina, a very simple device, getting rid of complex(& expensive optics).
Dr M. Tauseef Omer
FCPS Resident
Dept of Paediatric Medicine & Neonatology
MAYO Hospital,King Edward Medical University,
Lahore, Pakistan.
contact@tlabs.pk
tauseef_ravian153@hotmail.com
www.tlabs.pk
During my house job rotation in East Medical Ward, Mayo Hospital,Lhe, my seniors introduced me to this instrument, direct opthalmoscope. The model they carried back then was the same one as in photograph above.With simple instructions given by them, after an effort of 2 minutes , i was able to see just a glimpse of vessels in retina. It was all very beautiful. But i could not locate fundus or track vessels.
Very few doctors carried the instrument with them as it was ëxpensive. And so, everyone relied on eye department for trivial retinal findings.
The physics that is involved in opthalmoscope is a really simple one. I illustrate it here as :
The rays of light from bulb(a) get collimated(parallel) by lens(b) , mirror(c) deflects them 90 degrees towards patient's eye which then go through patient's pupil>lens>strike retina > return from retina>lens>pupil and come back just near to mirror of ophtalmoscope, and physician sees those light rays through aperture(g).
From this physics, i ascertained the issue, an issue that"direct opthalmoscopy is hard to learn ,and not everyone can do it in the first go".
I guessed that the distance "i" is making the job tedious.
The second issue , "expensive" instrument, was because of the optics used in the instrument.
To eliminate all optics, i came up with an idea, to use Surface Mount Device type Light Emitting Diode as a light source, on a piece of card or preferably Printed Circuit Board, and make an aperture in it so that the distance "i"is considerably reduced.
I also found out that , if SMD LED is placed close to cell phone camera , very close , then cellphone camera works like a fundoscope. If you understand photography, then you know that FLASH is placed a bit far from Camera so that RED EYE REFLEX is minimized. I brought LED closer to camera, to make RED REFLEX more pronounced , and once very close to eye, to see through eye.
Follow below.
The above two diagrams illustrate well the idea. Distance "i"is considerably reduced.
The initial version made according to the plan looked very much like this :
This device was named as OptiCard, it had an aperture in its upper piece for direct fundoscopy (without cell phone camera), and the device could be attached to cellphone camera by folding the upper piece of card, as below :
The image of retina visualized using cellphone :
By reducing the distance "i", everyone can do fundoscopy in the first go.
More research data is needed however, to prove my point.
(I have shared the link to my research paper below).
So the instrument as per end of year 2017 , looked very much similar to the one in above photos.
It had two pieces.
In 2018,
I came up with another idea, to make aperture in the card below LED.
I used printed circuit board, and SMD switch and the final device looks like :
Front
Back
Attached to cellphone Camera
The video demonstration of the gadget is as :
The research paper published in Journal of College of Physicians and Surgeons Pakistan (JCPSP) is here:
The project is still ongoing, and I have multiple updates in my mind.
I have started collecting a digital record of retinal findings of patients , the "Photo FollowUp".With the intent to create a less expensive device I found an easier way too , to visualize retina, a very simple device, getting rid of complex(& expensive optics).
Dr M. Tauseef Omer
FCPS Resident
Dept of Paediatric Medicine & Neonatology
MAYO Hospital,King Edward Medical University,
Lahore, Pakistan.
contact@tlabs.pk
tauseef_ravian153@hotmail.com
www.tlabs.pk
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