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This presentation is orginaly uploaded to http://kpkmedicalcolleges.tk by Dr.Suleman
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Lens & Cataract
Congenital Defects of Lens
Congenital Aphakia Lenticonus and Lentiglobus Lens Coloboma Mittendorf’s Dot (Hyaloid Corpuscle) Epicapsular Star Micro-sphero Phakia Ectopia Lentis
Components of tunica vasculosa lentis
Congenital Defects of Lens
Congenital Aphakia Very rare Associated other eye malformations ± Primary: Lens plate fails to form Secondary:
More common than primary aphakia
It occurs when developing lens is
spontaneously absorbed
Congenital Defects of Lens
Lenticonus and Lentiglobus Lenticonus
UL
Axial in location
Localized cone-shaped deformation of
anterior / posterior lens surface
Posterior more common
Anterior (Alport syndrome) and often BL.
Posterior lenticonus viewed by retroillumination
Congenital Defects of Lens
Lenticonus and Lentiglobus Lentiglobus
Shperical localized lens surface deformation
Posterior> anterior May be associated with lens opacities Retinoscopy – distorted/Myopic reflex
(center) Retroillumination – Deformation visible
in red reflex as “Oil droplet” (cf. “Oil droplet” of galactosemia)
Congenital Defects of Lens
Lens Coloboma An anomaly of lens shape
Primary: wedge shaped defect in lens
periphery (isolated anomaly)
Secondary: flattening/indentation of
lens periphery due to lack of ciliary body
or zonular development
Coloboma of the lens (arrow) viewed by retroillumination
Congenital Defects of Lens
Lens Coloboma Location:
Inferiorly May be associated with uveal
colobomas
Adjascent lens opacities ±
Cortical/capsular thickening
Zonular attachments in the region of
coloboma usually show some defects
Congenital Defects of Lens
Mittendorf’s Dot (Hyaloid corpuscle)
Common anomaly observed in many
healthy eyes Remnant of posterior vascular capsule of
tunica vaculosa lentis Small, dense white spot inferior nasal to
posterior pole of lens Sometimes associated with a fibrous tail
projecting into the vitreous body
Components of tunica vasculosa lentis
Congenital Defects of Lens
Epicapsular Star
Remnant of tunica vasculosa lentis
(common)
Star shaped brown/golden flecks on
the central anterior capsule
Often called chicken tracks
Congenital Defects of Lens Micro-sphero-phakia
Lens spherical and small in diameter (Eye highly myopic)
Entire lens visible through dilated pupil Isolated anomaly/associated with other
anomalies like: Marfan syndrome Peter’s anomaly Alport syndrome Weill-Marchesani syndrome Congenital rubella Lowe syndrome
Congenital Defects of Lens Micro-sphero-phakia
Lens may block pupil (ACG):
Miotics aggrevate
Cycloplegics relieve an attack of ACG
Treatment: Laser iridotomy
Developmental defects
Ectopia lentis Ectopia lentis: Displacement of the lens
Congenital Developmental Acquired
Subluxation: Partial displacement from its normal position but remains in the pupillary area
Upward lens subluxation in Marfan syndrome
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