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Cataract. Dr/ Mervat El-Shabrawy Ass. Prof. of Ophthalmology- Faculty of Medicine Suez Canal University. Definition:. Opacity of the lens. What is the origin of the term Cataract? In the past, there is a wrong believe that the humor of the brain falling inside the eye. Classifications:.
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Cataract Dr/ Mervat El-Shabrawy Ass. Prof. of Ophthalmology- Faculty of Medicine Suez Canal University
Definition: • Opacity of the lens. What is the origin of the term Cataract? • In the past, there is a wrong believe that the humor of the brain falling inside the eye.
Classifications: (1) Etiological: Congenital Acquired 1- Senile 2- Traumatic 3- Complicated 4- Pathological 5- Deficiency 6- Occupational 7-Radiation 8- Toxic
(2) According to the age (Surgical classification) Soft Hard Below 25 Y.O. After 25 Y.O. (3) According to the site Capsular Nuclear Cortical
* CongenitalCataract * • N.B.: - Congenital Cataract:= Lens opacity present at birth. - Infantile Cataract:= Lens opacity that develop during the 1st year of life. - These 2 terms are fused together & some physicians preferthe termdevelopmental cataract.
Morphological types : • Anterior polar cataract. • Posterior polar cataract. • Zonular cataract. • Coronary cataract. • Punctate cataract. • Total cataract.
1- Anterior Polar Cataract • Etiology: * Congenital - Bilateral. - Occurring at the time of the lens vesicle separation from surface ectoderm resulting in delayed formation ant. Chamber with contact between ant. Pole & cornea. * Acquired - Unilateral. - Due to small central perforation of corneal ulcer.
Clinical Picture: * Symptoms(By parents) -White dot at the center of the pupil * Signs -Small white opacity in the center of the pupil at the ant. pole of the lens. - No marked visual affection (as it is far from the nodal point).
2- Posterior Polar Cataract • Etiology: -Persistence of hyaloid artery. • Clinical Picture: * Symptoms:Usually no symptoms. * Signs: -Disc shaped opacity at the post. Pole. - Marked visual affection due to it is near to nodal point.
3- polar Cataract • Etiology: 1)Hereditary. 2) Malnutrition of the mother during pregnancy. • Clinical Picture: * Symptoms: -White colour of the pupil. - Child doesn’t see well.
* Signs: 1) Diffuse illumination: -Central disc opacity with clear lens around it. - There may be linear extensions. 2) Slit lamb examination: -Opacity arranged in one or many concentric zones. - lens substance outside & inside the affected zones are clear. 3) Red Reflex: - Dim central. - Bright peripheral
4- Coronary Cataract • DevelopmentalCataract. • Appears at puberty due to defect in the growth of lens fibers at childhood. • Appear clinically as a corona of oval opacities near the periphery.
5- Punctate Cataract • DevelopmentalCataract. • Multiple small bluish dots scattered all over the lens. 6- Total Cataract • The lens is opaque. • Etiology: Infection of the mother in the first 3 months of pregnancy by Rubella virus.
Complications of congenital cataract: • Occurs only if the opacity affects the vision: - Unilateral cataract: Squinting of the eye. - Bilateral cataract: Nystagmus.
Management of a case of congenital Cataract Evaluation Indication of surgery Surgical techniques Correction of Aphakia
(1) Evaluation: A- The Eyes: - unilateral versus Bilateral. - Density. - Morphology. - Visual functions. Q) How can you test visual acuity during infancy? - By special tests as Preferential looking. B- The patient: • Examined by Pediatrician for any congenital anomaly. • C- Parents: • May gives clue to the etiology.
(2) Indications of surgery: A) Bilateral advanced cataract:surgery at once. B) Bilateral & fundus can be seen:don’t require surgery. C- Bilateral & fundus seen only by indirect ophthalmoscope: - Good near vision: Postpone surgery. - Poor near vision: Surgery at once.
(3) Surgical techniques: • Old Operations: 1- Needling operation. 2- Needling & curette op. * Complications of old operations: - dense after cataract. - Secondary iritis. - Secondary glaucoma. - Delayed unexplained retinal detachment.
Recent Operations: 1- Simple Aspiration. (irrigation & aspiration) 2- Lensectomy.
(4) Correction of Aphakia 1- Contact lens. 2- Epikeratophakia. Q) Why we don’t do ICCE??? - Presence of strong zonules & strong hyaloid capsular ligament.
Acquired Cataract1- Senile Cataract: • Def. - Bilateral progressive lens opacity affecting the old people not suffering from local or general diseases. • Etiology:Unknown But theories: 1- Disturbance of lens capsule permeability. 2- Disturbance in lens metabolism. 3- Ultraviolet rays. 4- Endocrinal disturbance. 5- Hereditary.
Classification: - Cortical: Most common type. - Nuclear. - Cortico-nuclear. • Pathology: • Hydration. • Coagulation of lens proteins.
Senile Cortical Cataract • C/P: - Symptoms – 1) gradual painless diminution of vision. 2) Fixed black spots. 3) Diminution of vision at night??. 4) Uniocular diplopia or polyopia. 5) Index myopia??. 6) Change in colour value.
N.B. • Secondary glaucoma in intumescent cataract due to Phacomorphic glaucoma. • Secondary glaucoma due to hypermature cataract is called phacolytic glaoucoma. • Morgagnian cataract: one of hypermature stage. If present = Atypical hypermature. • Incipient cataract & senile nuclear sclerosis = Grey pupil. Differentiated by red reflex.
Complications • Sec. glaucoma. • Subluxation or dislocation of the lens due to degenerations of the zonules. • Sec. uveitis. • Endophthalmitis phacoanaphylactica.
Senile Nuclear Cataract • Senile nuclear sclerosis: - Physiological process. - Old lens fibers becomes compressed towards the center with loss water. So nucleus increase in size & volume but remains transparent.
Senile nuclear cataract - Pathological senile nuclear sclerosis in which the transparency is affected. • Symptoms: 1) Gradual diminution of vision. 2) Defective vision at day “Photopic vision” 3) Index myopia.
Signs: • Do not the stages of cortical cataract. • Red reflex: red ring around opacity. • Due to deposition of melanin formed tyrosine, Lens may have a color: • 1- Black: Cataract nigra. • 2- Brown: Cataracta Brunescence.
-Differential Diagnosis:1- Gradual painless diminution of vision: 2- Incipient from senile nuclear sclerosis: By R. reflex.
Treatment • I.C.C.E with or without I.O.L implantation. • E.C.C.E // // // // // • Phaco-emulsification with or without I.O.L implantation.
Traumatic Cataract • Lens opacity as a result of ocular trauma. According to the type of trauma Sharp trauma Blunt trauma Small but high speed F.B Linear opacity Usually cause post. Cortical rosette shaped Cat. Large but low speed F.B Cloudy swollen with rupture capsule
Complications: • - Iritis. • - 2ry glaucoma Treatment: • 1- Medical: Immediately after trauma, * Rest * Atropine * Cortisone. • 2- Surgical: Later, * If light projection is good, indicating good retinal function.
N.B.1 : In Blunt trauma we may find Vossius ring “ Brown ring on the ant. Lens capsule cue to impress of the pupillary border or the iris on the lens. • N.B.2 : Electrical trauma: - Due to passage of high electric current through the body. - May occur within days or after years. - Pathology: Change in lens capsulepermeability. - Morphology: Subcapsular vacuoles causing opacity.
Complicated Cataract • Lens opacity due to local disease in the eye. • Etiology: - Conjunctiva. - Cornea: Sever corneal ulcer. - Sclera: Acute scleritis. - Uveal tract: Iridocyclitis. - Lens: Subluxation & dislocation. - Glaucoma. - Retina: R.D. , R.P. & retinoblastoma.
Pathology: - Interference with lens nutrition. - Effect of toxins present in aqueous or vitreous. • N.B. Why lens opacity is usually posterior cortical?? • Thin posterior capsule. • No protective subcaosular epithelium.
Types: 1) Anterior segment. 2) Posterior segment. • In both types:When the whole lens become opaque, it may be difficult to differentiate from senile cataract. • Treatment: • Cataract operation. • According to the cause.
Pathological Cataract • Lens opacity due to systemic disease. • Diabetic Cataract: a- True: - Young patient with uncontrolled D.M. - Milky white dots under ant. & post. capsule. - Soon, the whole lens become opaque. b- False:The same as senile but earlier. * Treatment: Cataract extraction after control of diabetes.
2) Hypoparathyroid Cataract: - Low serum calcium which is important for lens metabolism. - Subcapsular opacities “Malformation of new lens fibers”. - Treatment:E.C.C.E & I.O.L. 3) Ankylostoma Cataract: Due to: - Anemia “Malnutrition of the lens”. - Ankylostoma toxins.
Deficiency cataract - Interfere with normal lens nutrition or metabolism. a- Galactosaemia. b- Mannosidosis. c- Fabry’s disease. d- Deficiency of vit. C or D. Occupational cataract - Glass blowers cataract.
Radiation Cataract X-rays & Gamma rays • Pathology: * Injury to the lens fibers directly. * Injury to the cilliary body: Abnormal aqueous Disturbance of lens nutrition Opacity in posterior cortex. Toxic cataract - Anterior subcapsular:Miotics, Gold. • Posterior subcapsular:Corticosteroids “ topically or systematically”.