Download - The Slit Lamp Exam

Carla’nne Dukes, DO, MBA, FACEPCarla’nne Dukes, DO, MBA, FACEP Emergency Medicine Residency DirectorEmergency Medicine Residency Director St. Joseph’s Mercy of MacombSt. Joseph’s Mercy of Macomb Clinton Twp, MIClinton Twp, MI [email protected]@trinity-health.org

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http://eyelearn.med.utoronto.ca/default.htmhttp://eyelearn.med.utoronto.ca/default.htm University of TorontoThe Ophthalmology University of TorontoThe Ophthalmology

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The Slit Lamp ExamThe Slit Lamp Exam

Although the slit lamp Although the slit lamp has become almost has become almost universally available universally available to the emergency to the emergency room physician, a room physician, a reluctance on the part reluctance on the part of many physicians to of many physicians to use this device persists use this device persists

MagnificationMagnification

a patient who came to a patient who came to the emergency with a the emergency with a sensation of a foreign sensation of a foreign body in the eye. The body in the eye. The emergency physician, emergency physician, without the aid of without the aid of magnification, spent 20 magnification, spent 20 to 30 minutes trying to to 30 minutes trying to remove the small remove the small brown dot that is just brown dot that is just visible in this slide. visible in this slide.

MagnificationMagnification

the same patient the same patient using the using the magnification, the magnification, the brown dot can brown dot can actually be seen to actually be seen to be two brown nevi, be two brown nevi, benign pigmented benign pigmented accumulations of accumulations of cells cells

FluoresceinFluorescein & Cobalt Blue Filter & Cobalt Blue Filter

By the fluorescence elicited by the cobalt By the fluorescence elicited by the cobalt blue illumination, subtle lesions of the blue illumination, subtle lesions of the cornea, including smaller corneal cornea, including smaller corneal abrasion, herpes simplex, dendritic ulcers abrasion, herpes simplex, dendritic ulcers and foreign bodies can be easily seenand foreign bodies can be easily seen

Landmark IdentificationLandmark Identification

Landmark 1 will be the anterior surface Landmark 1 will be the anterior surface of the cornea, the first to be struck by the of the cornea, the first to be struck by the slit lamp beam. slit lamp beam.

Landmark 2 will be the posterior surface Landmark 2 will be the posterior surface of the cornea where the slit lamp beam of the cornea where the slit lamp beam exits from the cornea.exits from the cornea.


Landmark 3 will be the plane of the iris Landmark 3 will be the plane of the iris and lens surface. and lens surface.

Landmark 4 will be the posterior surface Landmark 4 will be the posterior surface of the lens which has a reverse curve and of the lens which has a reverse curve and can be most easily seen with the beam can be most easily seen with the beam angled more closely to the line of angled more closely to the line of observationobservation


landmarks 1, 2 and 3 landmarks 1, 2 and 3 are out of focus but are out of focus but landmark 4 is in focus landmark 4 is in focus and a white opacity and a white opacity on landmark 4 is seen on landmark 4 is seen - the typical posterior - the typical posterior subcapsular cataract subcapsular cataract produced by extended produced by extended use of topical steroids use of topical steroids and easily identified and easily identified with the slit lamp with the slit lamp


The nature of these The nature of these lines becomes lines becomes apparent with the apparent with the angled slit beam angled slit beam


Between landmarks 2 Between landmarks 2 and 3 a vertical and 3 a vertical transparent membrane transparent membrane may be seen which may be seen which peels off the back of peels off the back of the cornea superiorly the cornea superiorly and curls up upon itself and curls up upon itself inferiorly. The upper inferiorly. The upper line seen in the flat- line seen in the flat- illumined view was illumined view was where the endothelium where the endothelium had been peeled off the had been peeled off the back of the cornea back of the cornea


Landmarks 4 and 3 can Landmarks 4 and 3 can be seen, 1 and 2 are out be seen, 1 and 2 are out of focus. Between of focus. Between landmarks 4 and 3 there landmarks 4 and 3 there is a big, diffuse yellow is a big, diffuse yellow haze. Its position haze. Its position relative to landmarks 3 relative to landmarks 3 and 4 reveals that it is and 4 reveals that it is right in the center of the right in the center of the lens and hence it is the lens and hence it is the nucleus. nucleus.


a mature cataract a mature cataract is being viewed is being viewed with flat with flat illumination. illumination. This reveals no This reveals no information with information with regard to the regard to the position of the position of the cornea relative to cornea relative to the lens and iris, the lens and iris,

Landmark IdentificationLandmark Identification the line of slit beam the line of slit beam

on the front of the on the front of the iris is seen to be iris is seen to be coincident with the coincident with the slit beam exit on the slit beam exit on the back of the cornea, back of the cornea, indicating no indicating no anterior chamber at anterior chamber at this site and the iris this site and the iris is plastered against is plastered against the back of the the back of the cornea.cornea.


Observe the relation Observe the relation between landmarks 1 between landmarks 1 and 2. One and 2 and 2. One and 2 proceed from above to proceed from above to below with uniform below with uniform separation until just separation until just below the mid-point. below the mid-point. Landmark 1 can be seen Landmark 1 can be seen to dip in and out, to dip in and out, revealing a shallow pit revealing a shallow pit which was left after which was left after foreign body removal. foreign body removal.


landmarks 1 and 2 can landmarks 1 and 2 can be seen coming out be seen coming out from below and from below and joining, indication that joining, indication that the stroma of the the stroma of the cornea is gone in the cornea is gone in the central portion as a central portion as a result of multiple result of multiple surgical procedures on surgical procedures on this cornea this cornea


The light is coming The light is coming from the observer's from the observer's right-hand side and right-hand side and strikes first of all the strikes first of all the cornea, and then the cornea, and then the iris and lens. A large iris and lens. A large gap may easily be gap may easily be seen between the slit seen between the slit beam on the cornea beam on the cornea and the slit beam on and the slit beam on the lens. the lens.

Thinning the CutThinning the Cut

DepthDepth

the cornea of an the cornea of an eight-year-old boy is eight-year-old boy is demonstrated in demonstrated in which the wound to which the wound to his cornea is V-his cornea is V-shaped and resulted shaped and resulted from a brass hose from a brass hose coupling slipping coupling slipping and flying up and and flying up and cutting the front of cutting the front of his cornea his cornea

DepthDepth

the slit lamp beam the slit lamp beam has been moved has been moved further to the left further to the left and the line of the and the line of the cut in the cornea cut in the cornea again is again is demonstrated to be a demonstrated to be a shelving rather than shelving rather than a penetrating a penetrating incision. incision.

DepthDepth

Easy Miss without Slit LampEasy Miss without Slit Lamp

An enamel flake cut the eye in a shelving An enamel flake cut the eye in a shelving manner which was self-sealing so that there manner which was self-sealing so that there was no pupillary distortion. There was no was no pupillary distortion. There was no prolapsed iris, and without the application of prolapsed iris, and without the application of the angled slit beam to achieve serial optic the angled slit beam to achieve serial optic sections the discovery of the wound which did sections the discovery of the wound which did in fact penetrate to the interior of the eye could in fact penetrate to the interior of the eye could not have been discerned at the initial not have been discerned at the initial encounter. encounter.


A nail slipped and stuck in the patient’s eye. He came A nail slipped and stuck in the patient’s eye. He came to the emergency department, but the emergency to the emergency department, but the emergency intern, who was on his first week in service, had no intern, who was on his first week in service, had no facility with the slit lamp. He did use fluorescein dye facility with the slit lamp. He did use fluorescein dye and found that there was staining, but was and found that there was staining, but was unsuccessful in reaching the ophthalmologist on call. unsuccessful in reaching the ophthalmologist on call. He brought the patient back to the clinic two days He brought the patient back to the clinic two days later at which time the typical iris distortion, linear later at which time the typical iris distortion, linear discontinuity on the cornea and protruding iris discontinuity on the cornea and protruding iris indicated a penetrating wound of the eye. indicated a penetrating wound of the eye.


Magnication would have revealed protruding Magnication would have revealed protruding iris tissue and the diagnosis could have been iris tissue and the diagnosis could have been made at the initial encounter. After the eye made at the initial encounter. After the eye was sewn up the patient was found to have a was sewn up the patient was found to have a vitreous abscess. This was removed surgically vitreous abscess. This was removed surgically following which the retina detached. following which the retina detached.