Hello! My name's Sirjhun Patel and i'm ophthalmology doctor.
In this short video i'll be giving an introduction on the basics of using a slit lamp
i'll be showing you how to perform a systematic approach to the anterior segment examination
this video won't include an introduction to the posterior segment examination
as this is a more advanced skill using an extra lens this is not expected at a basic level
now keep in mind that this is a practical skill and the video is adjunct so after you've
watched this video i strongly recommend heading down to the clinical skills area
and practicing in pairs if safe to do so the slit lamp allows detailed visualization of the anterior
and posterior segment of the eye it uses the binocular compound microscope and adjustable
illumination system it provides a stereoscopic or 3d view and a magnified view it also facilitates
for the patient and the examiner to be seated comfortably so let's talk about the main features
first keep in mind that there are slightly different models of slit lamps available but
in general they have similar layouts the on off switch is under the table and can be found here
next we need to set up our eyepieces set your interpolated distance by moving the eyepieces
in and out then if you have a prescription you can put it in here personally i prefer to keep
it at zero and keep my glasses on if you have a glasses prescription you can try keeping your
glasses on and off and i would recommend trying both and find what's more comfortable for yourself
before you start make sure you unlock the locking screw to loosen the slit lamp to
move the slit lamp you have two options large movements or fine movements by using the joystick
to move the slit lamp up and down you rotate the joystick clockwise and anti-clockwise
turn this lever all the way to the left for unfiltered white beam you can adjust the
brightness with this control here to adjust the beam height turn this control clockwise
and anti-clockwise adjust the beam height to its highest which is about eight millimeters
using the measurement on the bean height can also be used to measure lesions in the eye such as
corneal ulcers the control for the beam width is found here on the illumination arm and you
should try and become comfortable in moving the illumination arm around as you will find us doing
in this examination it should be noted that if you do increase the width of the beam too much it does
become uncomfortably bright for the patient and you should be mindful of this throughout your
examination the magnification can be adjusted by turning this control here there's also a
teaching observation arm here this allows the second person to observe the examination through
another eyepiece like all patient interactions make sure you use appropriate hand hygiene and ppe
introduce yourself to the patient and explain to them you'll be performing an eye exam using a
microscope answer any questions they may have and make sure they're happy before you proceed adjust
the patient's chair and the slit lamp to ensure that it's comfortable height for the patient you
can move the slit lamp up and down as shown here note that some slit lamps have a lever instead
of buttons you should also remember to adjust your own seat to ensure that you're comfortable
before you begin you need the patient's eyes to be at the level of the markers shown here
you can adjust the patient's chin rest by rotating this control here
ideally you should be in a dimly lit room but for teaching purposes we're leaving the light on
when examining the anterior segment it's important to take a systematic approach
when using a slit lamp the basic approach for anterior segment is looking at the eyelids
the conjunctiva and sclera the cornea anterior chamber the iris and then finally the lens
ideally you want to begin with a low magnification to get your bearings and
then increase when appropriate you should try and become comfortable in moving the illumination arm
and adjusting the beam properties throughout the examination as we show in this example
start with the eyelids examine both the upper and lower eyelids look at the eyelashes
are there any loss of lashes changing color or malposition of eyelashes to note
at the eyelid margin look for signs of inflammation or any visible lumps
then move on to the conjunctiva beneath this is the white sclera look for redness hemorrhage
foreign bodies or any other lesions or lumps ask the patient to look in all directions of gaze for
full assessment next move on to examining the cornea this is the clear window at the front of
the eye and can be slightly more challenging to examine as it requires accurate focus
move the illumination arm so that it's at an offset from your view
and then turn the brightness up you should see a cross-section of the cornea in clinical practice
you can increase the magnification and you should be able to visualize the different layers such
as the epithelium stroma and endothelium as shown here if you shorten the beam and turn
up the illumination you can assess the anterior chamber you should look for cells flare or blood
adjust your beam again to examine the iris assess the structure colour and movement of the pupil
finally examine the lens moving your beam at angle and focusing beyond the pupil you should
be able to visualize the crystalline lens and assess for a pacification
note that if the patient has had cataract surgery an intraocular lens implant may be in place
then repeat this process for the other eye an additional test which
you should be aware of is use the floor scene in assessing epithelial defects on the cornea
instill one drop of one percent fluorescein into the patient's eye to make fluorescein fluoresce
bright yellow green you need to use a cobalt blue filter turn the beam height control through one
hard click and it should turn this color then widen the beam width and increase the brightness
if there is an epithelial defect then the fluorescein will uptake in the area
where it fluoresces bright yellow green this method
can be helpful to detect pathology such as corneal abrasions and corneal ulcers
so this concludes the basic anterior segment examination using a slit lamp note that there
are many more illumination and viewing techniques to use with a sit lamp but in this video we just
showed the basic technique in examining the anterior segments we suggest that you try
and practice on your colleagues and peers and put this theory into practice many thanks for watching
we hope this video was helpful and informative and we're very open to any feedback thank you