Lens Disorders

Lens disorders 

Marwan S.Salman M.D

Ass.Professor of Ophthalmology
Tikrit university , college of medicine 

Anatomy of crystalline lens  

Crystalline Lens Of Eye

• Transparent, biconvex, avascular structure enclosed by a 

capsule(basement membrane secreted by lens epithelium)

• Approx. diameter is 10mm

• Lens measures approximately 10 mm in diameter and 4 mm thick

• Suspended by zonular fibres

• Parts Of Lens

• Capsule

• Cortex

• Nucleus

• Anatomy Of Lens

• CAPSULE

• ANT CAPSULE

• Basement membrane of ant lens epithelium

• POST CAPSULE

• Basement membrane of cell lens that have nuclei near lens equator

• Thickest basement membrane in the body

WHAT IS A CATARACT ?

• Any opacity in the lens or it’s capsule 

whether developmental or acquired is 

called cataract

OR

Loss of transparency of crystalline lens 

is cataract

• Aging Changes

Nuclear changes (nuclear sclerosis)

• Hardening of nucleus starts as early as 20 

years of age.

• Increase in insoluble proteins

• Cholesterol level increases while 

phospholipid level decreases 

Symptoms Of Cataracts

• Hazy, fuzzy or blurred vision

• Double vision

• Frequent changes in spectacle 

prescriptions

• Feeling of having a film over the eye

• Colours appear dull

• Glare in bright daylight, and at night 

from bright light sources

Persone with cataract 

Acquired Cataract

• Senile cataract
• Presenile cataract
• Traumatic cataract
• Secondary cataract

• Age Related Cataract

Morphological classification

• Anterior subcapsular
• Posterior subcapsular
• Nuclear
• Cortical
• Christmas tree

SUBCAPSULAR CATARACT

Anterior subcapsular cataract

• Lies directly under lens capsule & there is associated 

fibrous metaplasia of anterior epithelium of the Lens

Posterior subcapsular cataract

• Lies just in front of posterior capsule

• Associated with posterior migration of epithelial cells of 

lens

• Patient troubled by headlights & bright sunlight

• Near vision is diminished more than distance Vision

NUCLEAR CATARACT

• Exaggeration of normal ageing
• May lead to 

temporary myopia from increase in 

refractive index of lens so patients 

may be able to read again without 

spectacles (second sight of the aged)

CORTICAL CATARACT

• Involves anterior, posterior or equatorial cortex.

• Opacities start as vacoules or clefts between lens fibers

• Later they may develop into radial spoke-like opacities

Christmas tree Cataract

• Uncommon

• Striking, polychromatic, needle-like deposits in the deep 

cortex or nucleus

• May be solitary or associated with other opacities 

• Nuclear sclerosis grading 

• Nuclear cataract 

• Posterior subcapsular cataract
• Abnormal red reflex 

• Hypermature  cataract
Morgagnion cataract  

Classification According To Maturity

• Immature

• Mature

• Hypermature

• Morgagnian

• IMMATURE CATARACT

Lens is partially opaque

• MATURE CATARACT

Lens is completely opaque

HISTORY

• Age of Onset

• Decreased Vision

• Painless,

• Effecting daily routine activity?

• Trauma

• Any Ophthalmological Problems

• Drugs Intake

• Exposure to Radiations

• Systemic Diseases H.T DM etc.

• Skin disease, joint pains, etc.

• Family History

EXAMINATION

• GENERAL PHYSICAL EXAMINATION

• SYSTEMIC EXAMINATION

OCULAR EXAMINATION

• Visual Acuity

• Adnexa

• Iris

• Conjunctiva

• Cornea

• Anterior Chamber

• Pupil

• Lens

• Vitrous

• Retina

INVESTIGATIONS

• Blood Glucose
• ECG
• Chest x-rays (PA view)
• Blood Complete Picture
• Any specific relevant investigation (if 

indicated)

OPTIMAL POST OP. REFRACTION

• If monocular correction is reqd.

In contralateral dense cataract or 

amblyopia ?

best post op refraction is -1DS

• If binocular correction is reqd
difference between the two eyes 

should not be more than 3DS. 

SURGICAL TECHNIQUES

• ICCE
• ECCE
• ECCE with posterior chamber
IOL implant
• Phacoemulcification

CONGENITAL CATARACT

• An opacity in the crystalline lens, 

present at the time of birth or 

appears with in first three months of 

life

• Occurs in about 3:10,000 live births
• 2/3 are bilateral
• Most common cause is genetic 

mutation, usually autosomal dominant 

(A.D)

• Congenital cataract 

AETIOLOGY

• IDIOPATHIC

35%

• HEREDITARY

25%

• INTRA-UTERINE CAUSES

20%

• Maternal infections

• Rubella

40-60%

• Mumps

10-22%

• Toxoplasmosis 5%

• Cytomegalovirus

• HSV

• Varicella

• Malnutrition

• Prematurity

• Drug induced

AETIOLOGY

• INBORN ERRORS OF METABOLISM

10%

• Lowe syndrome

• Galactosemia

• Mannasidosis

• Hypoparathyroidism

• Fabry disease

• Hypo/hyper glycemia

•

ASSOCIATED WITH OCULAR 

ANOMALIES 05%

• Microphthalmia
• Aniridia
• Coloboma

AETIOLOGY

• CHROMOSOMAL ABNORMALITIES

03%

• Down’s syndrome

• Turner syndrome

• Trisomy 13 & 18

• BIRTH TRAUMA

02%

• SKELETAL SYNDROMES

• Hallermann-Streiff-Francois syndrome
• Nance-Horan syndrome

Clinical Features

• Symptoms

– Decreased Vision
– Glare

• Signs

– Leukokoria
– Nystagmus
– Strabismus
– Amblyopia
– Microphthlamos

Morphological classification

• NUCLEAR CATARACT
• LAMELLAR (ZONULAR) CATARACT
• CORONARY CATARACT
• SUTURAL (STELLATE) CATARACT
• ANTERIOR POLAR CATARACT 

CLINICAL FEATURES

• White pupillary reflex

• Poor Visual Acuity

• Nystagmus

• CLINICAL EVALUATION

• Purpose:

To know:

• Cataract density

• Type of cataract

• Condition of retina and optic nerve

• Any associated ocular anomaly

•

CLINICAL EVALUATION

• Purpose:

To know:

• Cataract density
• Type of cataract
• Condition of retina and optic nerve
• Any associated ocular anomaly

Steps:

• Torch examination
• Examination under Anesthesia

• Ophthalmoscopy direct / indirect
• Associated ocular pathology

• Corneal clouding

• Microphthalmos

• Glaucoma

• Persistent anterior fetal vasculature

• Chorioretinitis

• Rubella retinopathy

• Foveal or optic nerve hypoplasia
• PAEDIATRIC CONSULTATION

• Dysmorphic features or suspicion of associated 

systemic diseases

LABORATORY 

INVESTIGATIONS

• TORCH screening
• Blood Complete picture

• Blood Glucose levels

• Serum calcium and phosphorus

• Urine:for reducing substances after drinking milk 

(glactosaemia) and chromatography for amino 

acids (lowe syndrome ) . 

• Chromosome analysis 

• Refer for syspicious other systemic diseases 

VISUAL FUNCTION 

EVALUATION

• Visual Acuity
• Follows light or not
• Colour targets
• Reaction to occlusion
• Pupillary Reflexes
• Fixation Reflex
• Visual Evoked Potentials(VEP)

DIFFERENTIAL DIAGNOSIS

• LEUKOCORIA

• Retinoblastoma

• Retinopathy of Prematurity

• Persistent Hyperplastic Primary Vitreous

• Retrolental Fibroplasia

• Toxocariasis

• Toxoplasmosis

• Incontinentia pigmenti

• Retinal Detachment

• Cytomegalovirus Retinitis

• RETINOBLASTOMA

• RETINAL DETACHMENT WITH A MITTENDORF SPOT

• PERSISTENT HYPERPLASTIC PRIMARY VITREOUS

• TOXOPLASMOSIS

• RETROLENTAL FIBROPLASIA

PROGNOSIS

• Visual morbidity may result from deprivation amblyopia, 

refractive amblyopia, glaucoma (10% post surgical 

removal), squint, secondary cataract and retinal 

detachment

• Mental retardation, deafness, kidney disease, heart disease, 

and metabolic disorders may be part of the presentation

Preoperative assessment for cataract surgery 

• Visual symptoms  

blur/glare ,distortion, color perception ,second sight

• POM

history of amblyopia, stabismus ,previous surgery e.g refractive 

surgery, trauma ,concorrent eye disease.

• PMH  

DM, HT,COAD, anasthetic history if GA considered . 

• SH 

occupation and daily task .

• DH  

warfarin , antiplatelet agent,topical medication . 

• VA 
• Cover/uncover test. 
• PUPILS

check RAPD , adequate dilitation

.

• Cataract

morphology ,density, maturity

• Others factors

• globe (deep set,small /large),
•

lids (blepharitis ,ectropion, entropion),

•

nasolacrimal (mucocele), 

• Cornea (scarring ,guttata)
• Anterior champer depth

• IOP
• IRIS ( PXS,iridodonesis,posterior synchiae, inducable mydrasis .
• Lens (PXS, phacodonesis, sublxation,type of cataract )
• Optic disc e.g glaucoma, neuropathy, macula (AMD ),fundus .  

• Complications 

Intra operative :
• Posterior capsule rupture without vitreous loss (2%)
• Posterior capsule rupture with vitrous loss(1%)
• Anterior capsule problem 
• Zonular dehiscence.
• Loss of nuclear fragment posteriorly  0.3%
• Choroidal haemorrhage 0.1%
Post operative early 
• corneal odema 
• Elevated IOP   

• Increase anterior inflammation 
• Wound leake 
• Iris prolapse 
• Endophthalmitis 
Post operative late
• Posterior capsule opacification 
• Cystoid macular odema 
• Retinal detachement 
• Corneal decompensation 
•

Ectopia lentis 

Displacement of the lens from its normal position . Te lens may 

be completely dislocated,rendering the pupil aphakic 

(luxated) , or partially displaced still remaining in the 

pupillary area (subluxated) ,ectopia lentis may be 

herediatory or acquired . Acquired causes included trauma,  

a large eye (i.e high myopia , buphthalmos), anterior uveal 

tumor and hypermature cataract . 

Without systemic association

1- familial ectopia lentis 
2- ectopia lentis et pupillae 

Ectopia lentis et pupillae 

With systemic association 
1- marfan syndrome 
2- weill - marchesani syndrome 
3-homocystineuria
4- hyperlysinaemia
5-stickler- syndrome 

• Mangement

The main complication of ectopia lentis are a-

refractive error (lenticular myopia ) b-optical 

distortion due to astigmatism c-glaucoma and 

rarely d- lens induse uveitis 

1- spectacele correction may correct astigmtism 

induced by tilt or the edge effect in the eye with 

mild subluxation aphakic correction may also 

afford good visual result if significant portion of 

visual axis is aphakic in the undilated state . 

2-Surgical removal of lens is indicated for cataract , 

lens induced glaucoma ,uveitis or endothelial touch