Fall 2014: Lecture 5: Diplopia and CN Palsies LECTURE!!! Flashcards
Diplopia
- Monocular
a. Ocular Problems
b. What else?
- a. Corneal, Cataract, Refractive, Maculopathy
b. Cerebral
Diplopia
- Binocular
a. The BIG one…
b. CNs? (3)
c. Supranuclear (4)
d. Neuro Muscular Junction (1)
e. What else?
- a. Strabismus
b. 3,4,6
c. INO, 1/2 Syndrome, Gaze Paresis, Skew Deviation
d. Myasthenia Gravis
e. EOMs
CASE HISTORY:
What should you ask? (First 4 are the TOP 4 QUESTIONS you SHOULD ASK!!!)
- Mono or Bino
- Direction
- Which Direction of Gaze is Worse
- Worse at DISTANCE of NEAR
* Onset, Frequency, When does it occur, Ocular and/or Neuro symptoms, Medical Hx, Hx of Trauma and Ocular Sx’s, Do u observe a Head turn or tilt.
GOALS of CASE Hx
- The Examiner should decide 3 things. What are they?
- a. If Diplopia or misalignment is Neurologic, ocular, or childhood strabismus problem
b. Which EOMs are involved
c. Cause
* Need to figure out what they mean by “DOUBLE” (True double or is it a GHOST IMAGE, SHADOW, HAZE, BLUR, or METAMORPHOPSIA)
Monocular Diplopia
- What are some causes?
a. Should find out if it improves with what test?
b. Confirm by covering what?
- RE, Cataracts, Irregular Astigmatism, Corneal Scars, Tear Film Irregularities, ERMs, Iridotomy
a. w/Pinhole
b. an Eye
Treatment Options for Monocular Diplopia
- What should u do?
- What is the NUMBER 1 CAUSE of MONOCULAR DIPLOPIA?
- Treat Underlying Problem!
a. Correct Refraction
b. Rigid CLs
c. Cataract Extraction
* *EDUCATION is KEY! - CATARACTS!!
Physical Examination
- External Examination
a. What should you assess?
- a. Eye movements individually (DUCTIONS) and together (VERSIONS) as well as in all positions of Gaze.
* Establish if Ocular misalignment is Comitant or Incomitant
Comitance
- Comitant: Define
a. 3 Examples - Noncomitant: Define
a. Most Commonly due to what?
b. Where is DEVIATION LARGEST?
c. Deviation will VARY with what?
- Magnitude of Deviation is SAME in ALL DIRECTIONS of GAZE
a. Decompensating Phoria
b. Congenital Strabismus
c. Less than 5 PD!!! - a. a Muscle or Nerve Problem (Acquired)
b. in the direction of action of the affected muscle
c. Deviation varies w/the eye used for fixation
Tests for Comitancy
- What 2 tests?
- COVER TEST and MADDOX ROD!
Testing a Pt with Double Vision
- What tests should be done?
- What should be done in cases of unexplained diplopia?
- What else could be done if needed?
- What other tests?
- VAs, VFs, Color Vision, Pupils, EOMs, BP
Ocular Health Exam (special Attention to eyelids, orbits, and Optic Nerve)
- CN TESTING
- FORCED DUCTION TESTING
- NPC, Saccades (HORIZONTAL, THEN VERTICAL!!), Vergence Ranges, Stereopsis, Hirshberg/Krimsky, CT, Maddox Rod, Parks 3 Step (I think it helps tell us if it’s a 4 CN Palsy), Worth 4 Dot
Hirshberg/Krimsky
- Which eye do u put the Prism over?
- Over the FIXATING EYE
Park’s 3-Step
- Step 1: What do you look for?
- Step 2: What are you looking for?
- Step 3: What kind of deviation are you looking for?
- Which eye has the HYPER DEVIATION? (Rt eye or Lt Eye?)
- Is DEVIATION GREATER on Rt GAZE or Lt GAZE?
- Is DEVIATION LARGER on RIGHT HEAD TILT or LT HEAD TILT?
Park’s 3-Step
- Which muscles are affected in a Pt w/a LEFT HYPERTROPIA, GREATER in RIGHT GAZE, and Greater on Left Head Tilt?
- If Left HYPER: Then it’s SO and IR. (Then you pick the OPPOSITE PAIR in the other EYE!)
Forced Duction Test
- Performed to determine what?
a. POSITIVE TEST = ?
b. Negative = ?
- If Restriction of Eye Movement is due to a Neurological Disorder or a mechanical Restriction
a. NO MOVEMENT = MUSCLE RESTRICTION (ORBITAL MASS)
b. MOVEMENT = NERVE PALSY
Treatment
- If Ischemic?
- Occlusion (4)
- Prism (2)
- Treat Systemic Risk Factors
- Eye Patch (Deprivation)
Bangerter Foil (Graded Occlusion…look at actual foil, doesn’t occlude 100% (can simulate a 20/25-20/400 occlusion)
Spot Patch (Scotch tape over the center of the lens. Still allows input, but disrupts enough signal to stop the double vision)
Tape
- Fresnel, Ground in Prism
Horizontal Diplopia Major Causes
- Name them (7)
- CI
- DI
- Decompensated Strabismus
- CN 6 Palsy
- CN 3 Palsy
- INO
- MG
Vertical Diplopia Major Causes
- Name them (4)
- CN 4 Palsy
- Thyroid-Associated Ophthalmopathy
- MG
- Skew Deviation
Horizontal Diplopia: CI
- What is it?
- Test results?
- Symptoms?
- Primary CI
- Secondary CI
- Eyes cant come inward.
- Eso greater at NEAR than distance, RECEDED NPC and BO RANGES
- Horizontal, INTERMITTENT DIPLOPIA at NEAR, HAs, Eyestrain, difficulty w/Near Work
- No abnormalities on Neuro-ophthalmic Exam
- Some other detectable Abnormality (Parkinson’s, Dorsal Midbrain Syndrome, Partial 3rd Nerve Palsy)
Horizontal Diplopia: DI
- Kind of disorder?
- Signs?
- Symptoms?
- Gradual Onset..Test?
- Acquired that causes COMITANT ESODEVIATION!!!
- Greater ESO at DISTANCE than at NEAR. Usually BENIGN
- Asthenopia, Motion Sickness, HAs, Photophobia, DIPLOPIA at DISTANCE!
- Imaging (MRI w/Contrast…Skull BASE TUMOR causing Partial 6th nerve palsy)
Horizontal Diplopia: Decompensating Phoria
- What happens when Fusion breaks Down?
- Type of DIPLOPIA SEEN?
- Pt may give Hx of DOING WHAT?
- Pt may have what type of Eso or Exo tropia?
- Latent Strabismus becomes a MANIFEST TROPIA and pt sees Diplopic
- At first, it’s Intermittent Horizontal Diplopia
- Intermittently Closing one eye to see clearly
- Comitant. May be able to “straighten” Eye w/Effort
EOMs Actions
- SR
a. Primary
b. Secondary
c. Tertiary - IR
- LR
- MR
- SO
- IO
- a. Elevate
b. Intort
c. Adduct - a. Depress
b. Extort
c. Adduct - a. Abduct
- a. Adduct
- a. Intort
b. Depress
c. Abduct - a. Extort
b. Elevate
c. Abduct
Etiologies of Palsies: Most common Identifiable Causes
- CN3
- CN 4
- CN 6
- Multiple (Any combo of 3rd, 4th, and 6th)
- Vascular
- Head Trauma
- Neoplasm
- Neoplasm
* All of them…Most common Group is UNDETERMINED
* Except of the Multiple…Most common is same as Most common identifiable cause.
CN 3 Palsy
- Where does it start?
- CN 3 Travels DOWN and thru what?
- While traveling down, it will pass what arteries?
a. Why is this so important?
b. If u have an Aneurysm and it compresses on CN3, what will u see? - After traveling thru the Cavernous Sinus it gets to what next?
- What happens here?
- What does the CILIARY GANGLION CONTROL?
- With CN 3, which Fibers cross and innervate muscles CONTRALATERALLY?
a. and Ipsilaterally?
- Midbrain
- Thru the CAVERNOUS SINUS
- Post. Cerebral Artery, Post. Communicating Artery, and the ICA.
a. Because the Pupillary fibers will lie along side these arteries!
b. a DILATED PUPIL - The Superior Orbital Fissure
- It branches into a SUPERIOR DIVISION (Controls SR and LEVATOR) and an INFERIOR DIVISION (MR, IR, IO)
- Sphincter and Accommodation
- SR
a. IO, IR, MR, and P… (reason y Pt can have a Bilateral Ptosis)
3rd Nerve Palsy Classficiations
- Complete
a. What muscles affected?
b. Where does the EYE SIT?
c. Ptosis?
d. Diplopia? - Partial
a. Muscles affected?
b. Ptosis?
c. Diplopia?
- a. ALL innervated by CN 3
b. “Down and Out”
c. YES
d. Usually don’t notice it due to I/L PTOSIS - a. 1 or more CN3 muscles affected (Mild to severe)
b. Yes and No (Mild to severe)
c. Can cause HORIZONTAL, VERTICAL, and/or OBLIQUE DIPLOPIA
3rd Nerve Palsy Classficiations
- Pupil Sparing
a. How do pupils react to light? - Pupil involved
a. LARGER PUPIL on what side of the PALSY?
b. Reaction to Light?
- a. Symmetric pupils and react BRISKLY to light
- a. on the same SIDE of the PALSY
b. POORLY REACTIVE to light.
Etiology of CN 3 Palsies
- Most Life Threatening?
- Best Px
- Most common cause in adults
- Most common acquired cause in kids?
- Most likely pupil sparing?
- Aneurysm
- Ischemic
- Ischemic/Vascular
- Traumatic
- Ischemic/Vascular
Etiologies of CN 3
Name them
- Ischemic/Vascular
- Compressive (Aneurysm, Neoplasm)
- Traumatic
- Inflammatory (MS)
- Infectious (Meningitis)
Nuclear 3rd Nerve Palsy
- Common?
- Ipsilateral Palsy?
- Contralateral?
- Levators involved?
- Causes? (3)
- RARE
- MR, IR, IO
- SR
- Yes… Bilateral Ptosis
- MS, Stroke, Tumor
Fascicular 3rd Nerve Palsies
- Often Associated w/”Crossed” Neurologic Signs
a. Benedikt’s Syndrome
b. Weber’s Syndrome
c. Claude Syndrome
- a. Lesion in RED NUCLEUS. (3rd nerve palsy w/a CONTRALATERAL ARM or LEG TREMOR)
b. Near CEREBRAL PEDUNCLE (3rd nerve palsy w/CONTRALATERAL ARM or LEG WEAKNESS)
c. 3rd nerve Palsy w/CONTRALATERAL TREMOR and ATAXIA!!!
Compressive 3rd Nerve Palsy! (KNOW THIS INFO!!)
- Aneurysm
a. MOST COMMONLY where?
b. Acute/Late Onset?
c. % Pupil Involved?
d. Pain?
e. Emergency?
f. Dilate? - Neoplasm
a. Fast/Slow progressing?
b. Primary tumors of Oculomotor Nerve?
c. Tumors Adjacent to Nerve?
- a. at Junction of IC and Pos Communicating ARTERY!!!!
b. ACUTE
c. 86%
d. Yes…Persisting SEVERE PAIN
e. YES!
f. NO! Want doctor to see what is going on. - a. Slow
b. Neurinomas and SCHWANNOMAS
c. PITUITARY and Sphenoid Wing Meningioma