Heavy eye phenomena Flashcards
what are the features of heavy eye phenomena
study conducted found that the key features was a hypephoria or hypertropia
41 pts had more than 3dioptres of anisomyopia
lower eye = more myopic eye
ahp head tilt to lower more myopic eye
list 3 key features of heavy eye syndrome
- 68 anisomyopes
61% vertical deviation relating to the amoiutnof anisometropia
bsv is absent /poor if anisometropia is more than 6 diopters
amisoymopia is mostly axial (not lenticular)
list all the features of high myopia
unilateral high myopia
reduced visual acuity
amblyopia
hypotropia
exotropia
head tilt (side to the affected eye)
limitation of upgaze
psedopropotsis
increased axial length
myopic fundus
ptosis (not previously described)
what is the astrology of heavy eye syndrome
ateiology = axial anisomyopia
anatomical factors
size and shape of anisotropic eye
orbital anatomyabnromality
facial asymmetry caused by protrusion of more myopic side
how can axial myopia cause heavy eye syndrome
axial myopia
posterior segmented amorally distended
stretch vascular nerve structures
vertical muscle imbalance due to vascular rinsiffcineecy
higher levels of myopia - more abornlities in extraoculr muscles
how can biopsies cause heavy eye syndrome
increases intrsital connective tissue (interstitial connective tissue) = forming space
irregular muscle fibre edges
irregular muscle fibre structure
what is the management of heavy eye syndrome
maintain binocular function
ocular motility
prisms
decantation off lens
contact lenses
occlusion - amblyopia
what surgical management should be considered in heavy eye syndrome
eom surgery
must consider refractive error original refractive error
vertical deviation (hypotropia)
inferior rectus recession
knapp procedure
affected eye - highly myopic
how would a patient with heavy eye syndrome with facial asymmetry and proptosis be managed
unilateral orbital 2 wall decompression
improved psedvoprotposis
reduced hypotropia
later strabismus surgery for hypotropia
lateral strabismus surgery for hypotropia
outcome improved cosmesis and improved ocular alignment
what are the differential diagnoses for progressive et with myopia
- endocrine pathology
sagging eye syndrome
uncorrected hyperopic refractive error
high accomplishment/convergence/accom ratio
Duane syndrome
Myasthenia Gravis
thyroid eye disease
cranial nerve plays - (3rd, 4th, or 6th nerve palsy)
what are the features of progressive et with high myopia
very high myopia - more than 20 diopters
axial myopia
long axial length more than 27mm
staphlyoma
gradual onset et
progresses to strabismus fixus
unilateral/bilateral
what is staphlyoma
abnormal profusion of the oval tissue through a weak point in the eye ball
The protrusion is generally black in colour, due to the inner layers of the eye. It occurs due to weakening of outer layer of eye (cornea or sclera) by an inflammatory or degenerative condition.
what is the aetiology of progressive et with myopia
MRI evidence
LR shifts inferiorly (depression of globe & decreased ABDuction)
SR shifts nasally (ADDuction of the globe & decreased elevation)
Enlarged globe prolapses out of muscle cone superotemporally
Deviation = ET & HoT
Greater prolapse & muscle pathway displacement - greater limitations of OM
(Aoki et al, 2003)
what have mri findings shown about progressive et with high myopia
mri
herniation of globe
superotemporally
how might the lateral rectus and superior rectus be affected in the development of progressive et with high myopia
lateral rectus and Superior Rectus slip
age related changes of lateral rectus and superior rectus band
band of connective tissue
permits discolation of globe out of muscle tone
could be the cause of development
mri evidence shows this
