Congenital Cataract Surgery, Dr. Prabhat Devkota.pptx

DR.PRABHAT KIRAN DEVKOTA,
MBBS(TU), MD(NAMS)
PEDIATRIC CATARACT SURGERY

1. Management Of Congenital Cataract DR. PRABHAT DEVKOTA MBBS(TU ), MD(NAMS) 1 8/14/2024

2. CONTENT Types Clinical Features History Examination Investigation Management Complications Bibliography 2

3. 3

4. 4

5. 5

6. Symptoms of Pediatric Cataract White reflex in the pupillary area Poor vision Unsteady/ Shaky eyes Deviation/Crossing of the eyes Aversion to bright light Problems with night vision 6

7. Signs of Poor Vision Lenticular opacity Nystagmus Strabismus Child’s Behavior 7

8. Ocular Associations of Congenital Cataract Anterior Segment Microphthalmos E .g . Rubella Microcornea and S clerocornea Cloudy cornea ( Lowe syndrome and Fabry’s disease ) Glaucoma : Aniridia , Peters anomaly, Rubella, Lowe syndrome and Edward syndrome Uveitis : Fuchs H eterochromic I ridocyclitis and J uvenile C hronic A rthritis Iris C oloboma 8

9. Posterior Segment Vitreous strands: Sticklers syndrome Retinal abnormalities: – Retinopathy of P rematurity – Transient lens vacuoles – Retinal flecks: Alport syndrome – Salt pepper retinopathy of Rubella – Retinoblastoma: usually less common ( unaffected eye) 9

10. Systemic Associations of Congenital Cataract Maternal D rug I ngestion Maternal r adiation exposure Maternal infection E.g . Rubella Hereditary disorders E.g . Neurofibromatosis Metabolic disorders: Galactosemia , Fabry’s disease and Mannosidosis Chromosomal abnormalities: Down syndrome and Nance-Horan syndrome Dermatological conditions: Atopic dermatitis Systemic medications: Steroids Systemic I nfections Musculoskeletal disorders: Myotonic Dystrophy Other congenital abnormalities 10

11. PEDIATRIC CATARACT EVALUATION 11

12. History Age of onset Progression Birth history: birth trauma, birth anoxia, prematurity Antenatal history: maternal fever, rashes and drug intake Perinatal history Developmental milestones and developmental regression Family history of pediatric cataracts, pediatric ocular surgeries, thick glasses Prior ocular and systemic medications Systemic complains like seizures, joint pain and hematuria H/o trauma H/o radiation exposure H/o severe diarrhoea 12

13. Examination Visual acuity assessment Fixation and Following Teller cards test From birth to 3 years of age Optokinetic Reflex Vestibulo -ocular Reflex Visually Evoked Potential 13

14. 14 From 3years to 6years children

15. 15 For children >6 years

16. Distant direct Ophthalmoscopy: It is performed by using the direct ophthalmoscope to obtain a red reflex from both eyes simultaneously . This is a screening test that identifies strabismus and pathology like anisometropia , gross retinal pathology, large retinal detachment, and corneal, lenticular, or vitreous opacities. 16

17. Pupillary Response Retinoscopy Intraocular pressure (IOP) Ocular motility: Strabismus & Nystagmus 17

18. Anterior segment examination Fundus examination in undilated pupil (gives an idea of the significance of the cataract ) Dilated slit lamp examination for morphology of cataract. Dilated fundus examination 18

19. B-scan USG (only if posterior segment not visible) Observe for associated ocular anomalies Screening for any gross systemic associations Examination of parents and siblings 19

20. Biometry: Hand-held Keratometer , A-Scan axial length, IOL calculation with SRK II IOL formula IOL Master in co-operative children (if available) 20

21. Axial Length Measurement Ultrasonic method: Immersion technique Contact technique Optical method: Uses partial coherence laser Biometer measure time required for infrared light to travel to retina 21

22. Keratometry Reading 22

23. Factors to be taken into consideration in ???calculating the IOL power : Age Unilateral/Bilateral cataract Presence of A mblyopia Refractive error of other eye Refractive error of the earlier operated pseudophakic eye Whether the IOL implantation is primary or secondary Strabismus & Nystagmus 23

24. Special ocular situations ??Special systemic status (mentally challenged) aim for slightly lesser hyperopia or more toward myopia Prior results with the equipment Intraocular lens placement (sulcus/bag) 24

25. Intraocular Lens Formulas Intraocular lens (IOL) power calculation in children should aim for moderately hypermetropic postoperative refractive outcome to compensate for myopic shift which is expected in children due to axial elongation of the globe. IOL can be implanted in eyes with an axial length of more than 17 mm and corneal diameter of more than 10 mm SRK/T and the Holladay 2 formulae best postoperative outcomes in pediatric eyes with axial length less than 20 mm axial length 25

26. Amount of U ndercorrection :- According to Dahan et al: 20 % in children < 2 years 10% in children 2-8 years Same calculated IOL power in a child above 8 years 26

27. According to Prost et al, 20% undercorrection between 1 and 2 years of age, 15% undercorrection between 2 and 4 years, and 10% between 4 and 8 years of age are adequate . Enyedi's postoperative target refraction can be used for IOL power calculation according to age ( Enyedi’s Rule of 7) Age in years + Postoperative refraction = 7 For Eg : Age of child= 3 years Undercorrection = +4 D 27

28. Method of IOL Power Calculation IOL power = A₁ – (2.5) L – 0.9 K Emmetropic power = 118 – (2.5 L) – (0.9 K) Where, K = the corneal refractive power, L = the axial length & A = the IOL specific A-constant Example, If a child with 3 years by SRK II formula has +28 diopter as the calculated IOL power , one has to deduct 10% (28.00 – 2.80 = 25.2). Hence in the example one should implant 25 diopter. If the child was 1 year of age, then one has to deduct 20% ( 28.00 -5.60 = 22.40/22.5 diopter). Younger the child, more the undercorrection . 28

29. When keratometry is not possible, the following formula is used which provides the IOL power based on axial length alone 29

30. Intraocular lens placement - Age and target postoperative refraction 30

31. Reducing Technical Errors By using handheld keratometry under anesthesia: Prior speculum Axial length while the child is sleeping/under general anesthesia : Immersion technique At least axial length should be documented even if “ K” reading is not possible By analyzing the results of earlier surgeries By combined A-scan and B-scan in children with coloboma , posterior staphylomas and disc coloboma Abstain from contact lens for 4–6 weeks prior secondary IOL . 31

32. Contraindications for PCIOL Microcornea (< 9.5 mm) Children < 6 months (controversial ) Juvenile chronic arthritis Severe and recurrent intermediate uveitis Grossly subluxated lenses where there is no zonular support Hydrophilic foldable lenses are to be avoided temporarily, if vitreoretinal intervention may be required . Traumatic cataract with doubtful support 32

33. Anterior chamber IOL (ACIOL) are contraindicated in children Iris fixated lenses can be implanted if no posterior support is available Scleral fixated IOL (SFIOL) can be planned after effective eyeball growth is complete and amblyopia is taken care earlier. 33

34. Referral to Pediatrician for Screening Children < 1 year of age Any significant Maternal, Antenatal Or Birth history Cataracts associated with other anterior segment anomalies like M icrocornea , C oloboma , Peters anomaly, A niridia Suspicion of Rubella Any syndromic children ( Eg ; Down syndrome) Developmental delay Protein Energy Malnutrition (Kwashiorkor & Marasmus) Any specific cataract morphology suggestive of metabolic etiology All children with spontaneous subluxated lens Children with dysmorphic features Associated with any systemic signs & symptoms 34

35. Investigations In the absence of a definitive hereditary etiology following investigations are recommended : Complete Blood Count Blood Sugar Serology(HIV I&II,HCV,HbsAg ) Torch Titer ( Transplacental infection) Urinary Amino acid qualitative (Lowe syndrome) Urinary Amino acid quantitative (Aminoaciduria) Renal Function Test and Urine analysis ( Alport syndrome) Urinary Copper (Wilson’s disease) Urinary sediments ( Fabry’s disease) Reducing substance other than glucose ( Galactosemia ) Serum calcium & phosphorus Chromosome analysis 35

36. Treatment Options Pharmacological Optical Amblyopia Surgical options Pharmacological dilation is useful in visually insignificant cataracts ( Eg Anterior polar). Tropicamide (TDS) or homatropine (BD/TDS) a day can be used for dilatation. Appropriate optical correction, patching the better seeing eye, ensuring good compliance with the treatment recommendations and periodic follow-up improves the chances of attaining a better visual acuity outcome. 36

37. Indications for Surgery Cataract >3 mm in size Posterior location (close to nodal point) In the pupillary area Dense Nuclear cataract Posterior subcapsular / posterior polar cataract Retinal and fundus details not visible by Indirect Ophthalmoscopy Presence of Nystagmus or Strabismus Poor central fixation Reduced near vision, significant glare and a drop in stereopsis attributable to cataract 37

38. Visually Significant Cataract A cataract is said to be visually significant if it is: >3 mm in size Located in the pupillary area ( ie visual axis) More posterior location Not able to observe the disc and macula with direct ophthalmoscope . 38

39. Timing of Surgery Surgery is advised in visually significant opacities, i.e . >3 mm central opacity. Unilateral cataracts should be operated as early as possible 4 to 6 weeks of age and bilateral cataracts should be operated within 6 to 8 weeks of age Cataract surgery is planned after 6 weeks of age and if the child is fit for general anesthesia. 39

40. Poor Prognostic Indicators Dense cataract Central cataract Unilateral dense cataract (amblyopia is dense) Nystagmus Strabismus Late presentation Associated ocular anomalies. 40

41. Informed consent Written consent is required from the parents / guardians after having been informed about the risks and benefits of the surgery. Explain Prognosis Need for permanent (bifocal) spectacles Need for frequent topical medications postoperatively Signs of complications Schedule for follow-up visits 41

42. Treatment Aim: The main aim of the treatment is to clear the visual axis followed by postoperative visual rehabilitation with minimum associated complications. Principles : Urgent removal of visually significant congenital cataracts Immediate aphakic optical correction Amblyopia management 42

43. Historical Aspect From early to mid-20 th century , needling was performed for treatment of pediatric cataract. 1960 Scheie popularized the aspiration procedure where 2 mL syringe with 19 gauze needle used to aspirate the lens matter. Later with the evolution of ECCE and phacoemulsification in adult phacoaspiration & irrigation and aspiration was started. 43

44. 1978 With the development of automated vitrectors , Peyman used pars plicata approach where posterior capsule is removed, so chances of PCO significantly reduced . 1990 BenEzra utilized the anterior route ( limbal ) to perform posterior capsulotomy with anterior vitrectomy. 1997 Gimbal described posterior capsulorhexis with optic capture of intraocular lens (IOL ) for pediatric cataract. 44

45. Anaesthesia General Anaesthesia with paralysis and mechanical ventilation N il per oral (NPO ) is required Meals Hour of Fasting Heavy meals 8 hours Light meals/Formula Milk 6 hours Breast Milk 4 hours Clear Liquid 2 hours 45

46. Two main A pproach Pars Plana Appoach : Lensectomy through pars plana (being abandoned gradually) Corneolimbal Approach: Lens aspiration through limbal incision 46

47. Pars Plana Approach: Indicated mainly for neonates and infants under 2 years of age for whom IOL implantation is not intended immediately Requires vitrectome Location of pars plana in infant 1.5 to 3.5 mm from the limbus Advantages- can be performed relatively rapidly less iatrogenic damage to corneal endothelium and the iris two eyes can be operated at the same sitting Disadvantages- incarceration of the vitreous in the scleral incisions difficult in case of insufficiently dilated pupil 47

48. Corneolimbal Approach Sclero -corneal tunnel : When Rigid IOL implantation is intended, a larger limbal wound is needed to introduce the IOL. Clear Corneal Incision : When foldable IOL implantation is planned, the incision of <3 mm is required. 48

49. Painting & Draping done Wire speculum / Universal eye speculum is applied Superior rectus bridle suture applied Conjunctival Peritomy is done Cautery of bleeding points is done 49

50. Limbal Paracentesis is performed Staining of the anterior capsule with Trypan blue dye is done. Air bubble is introduced to enhance staining Trypan blue is washed out AC maintained with viscoelastics   50

51. Sclero -corneal tunnel is constructed 3 components: External scleral incision Sclerocorneal tunnel Internal corneal incision 51

52. Anterior Capsulorhexis Highly elastic anterior capsule poses challenges Manual Capsulorhexis with cystitome or Utrata Capsulorhexis forceps. The soft-shell technique uses cohesive and dispersive viscoelastics and Balanced Salt solution to form the chamber and protect corneal endothelium. 52

53. Aspiration of lens material: Multiquadrant hydrodissection with a cannula on a 2cc syringe with balanced salt solution (Ringers Lactate). Lens aspiration with coaxial/bimanual irrigation and aspiration cannula (Simcoe cannula). 53

54. If PPC is planned, Primary Posterior Capsulotomy (PPC) with Anterior Vitrectomy ( AV) is done. The posterior capsule may be left intact in some cases according to the patient's age and the type of cataract. A ccording to Age : PPC with AV :<8 years Intact posterior capsule : >8 years 54

55. IOL implantation : Primary IOL implantation is the preferred choice in child >6mo. Rigid IOL (PMMA), foldable hydrophobic/hydrophilic IOLs are used in children Viscoelastics are injected 'In-the-bag‘/ ‘Sulcus’ implantation of IOL The IOL is dialed into position 55

56. Lens-in-the-bag : The IOL haptics are placed in the bag fornices , while the optic is protruded through both capsulorrhexes to be captured beneath the posterior capsule remnants Bag-in-the-lens : The specially designed IOL has, at its periphery, a groove that contains both anterior and posterior capsule rims. 56

57. Wound Closure: Wash the viscoelastics Checking the Wound Integrity: Gently tap on dome of cornea or at limbus opposite to wound with hydro- cannula. Hydration of the side port Suturing is done with 10-0 Nylon Intracameral & Subconjunctival antibiotics is injected Antibiotic ointment and eyeshield is placed. 57

58. Indications for Primary P osterior Capsulorhexis Children < 8 years of age Children > 8 years who have a posterior capsule plaque. Corneal opacity/scar in pupillary area Nystagmus Children with poor vision in the other eye Mentally challenged children Patient coming from very remote areas and follow-up is difficult despite the best counseling services Other eye very early and dense PCO that was not amenable to YAG capsulotomy 58

59. Postoperative care: Post operative treatment Daily examination (torch, direct ophthalmoscope, Slit Lamp) Combination of antibiotic and corticosteroids drops every 1-2 hourly with mydriatic agent Retinoscopy Tapered gradually Follow up on 2 weeks, 6weeks, Monthly & Yearly 59

60. Amblyopia management: Patching of the better eye is frequently indicated in cases of unilateral cataracts or asymmetric bilateral cataracts Occlusion should be instituted soon after the surgery Treatment should continue for at least 8-10 years of age Overpatching should be avoided as it may hamper the development of binocular vision . 60

61. Time Interval between Cataract Surgeries There is at least 1 month interval In the presence of strabismus, the second eye surgery is delayed till the first eye takes up fixation Simultaneous bilateral IOL implantation is usually not performed 61

62. Bilateral Simultaneous Cataract Surgery Advantages: -Reduces the risk of subjecting the child to multiple anesthesia procedures -Shorter stay in hospital -Reduces the cost of 2 nd general anesthesia . Disadvantages: -Potential threat of bilateral endophthalmitis and bilateral blindness -Exposes the child for longer duration of anesthetia 62

63. Timing of Secondary PCIOL Implantation 3–4 years of age Planned earlier in :- – Unilateral cataract – Poor compliance with glasses – Contact lens intolerance 63

64. Intraoperative Complications Superior rectus bridle suture: Hematoma formation Tunnel related: Premature entry and button hole Difficulty in capsulorrhexis formation Iris prolapse Bleeding Collapse of the anterior chamber/ wound leak Positive intravitreal pressure ( Vitreous Upthrust ) 64

65. Postoperative Complications Early – Post - operative bleeding – Increased IOP – Corneal Edema – Post-op Uveitis – Postoperative iritis and fibrin membrane formation – Endophthalmitis – Iris prolapse – Pupil peaking – Hyphema – Glaucoma 65

66. 66

67. Late: – Posterior capsule opacification – Optic/Pupillary capture – Decentration of IOL – Capsular phimosis – Refractive surprises – Cystoids macular edema (very less) – Secondary glaucoma – Steroid-induced glaucoma – Iridocapsular adhesions – Secondary membrane formation – Synechiae formation – Corneal decompensation – Suture infiltrate – Retinal detachment 67

68. Posterior Capsule Opacification Primary posterior capsulorhexis and good anterior vitrectomy reduces the chances of PCO . Posterior capsule opacification occurs faster in children operated for traumatic cataract and complicated cataract. Slit lamp gives the best judgment on the nature of capsular opacification and direct ophthalmoscope examination gives the best guidance on the effect of PCO on the vision. 68

69. Guidelines for ndYAG Capsulotomy Direct Ophthalmoscope is the best guide for the visually significant PCO Least amount of energy is used initially and gradually increased Aiming at the center is avoided to avoid lens pitting A steroid antibiotic drop is given for a week following the procedure Refraction is differed for 2 weeks to allow settling of the dispersed membrane . Membanectomy is required if the PCO is dense 69

70. Visual rehabilitation after Cataract Surgery • Residual refractive error should be corrected as early as possible • Parents should be counselled for the need of regular follow ups and refractions . • Aphakia Unilateral Aphakia - Contact lenses preferred to avoid distortion due to glasses. Bilateral Aphakia - Spectacles and Contact lens • Pseudophakia - Spectacles and Contact lens 70

71. • Refractive error should overcorrected to leave the child slightly myopic. • Ensures relatively better vision for near and intermediate distances until around 3-5 years, when a bifocal segment may be prescribed . • Amblyopia prevention and treatment should start immediately with patching and topical cycloplegics . 71

72. • Patching regimen in the IATS study (Infant Aphakia Treatment Study) for unilateral cataracts: 1 hour/day for every month of age up to 8 months, the patch 50% of all waking hours . • Consider a secondary IOL in children not tolerating aphakic contact lenses or glasses 72

73. Aphakic Correction: Choices- Spectacles Contact lenses Intraocular Lens 73

74. Spectacles- Considered to be safest method Suitable for bilateral aphakia Advantages : Ability to change power to accommodate changing refractive error Less costly Disadvantages : Visual field restriction to about 30 degree High magnification 30 % Increases nystagmus Prismatic effect shifts the retinal perception leading to strabismus Cosmetically , optically and psychologically debilitating High weight and thicker glass 74

75. Contact lenses: Advantages Better optical correction than spectacles Can be used in unilateral/bilateral aphakia Power can be adjusted throughout Disadvantages Frequent losses Difficult & costly management Recurrent infections Corneal vascularizations Requires dedicated parents 75

76. Intraocular Lenses Best in unilateral cataract after 1 year of age. (<1 year, the IOL power is unpredictable) One time cost. Require less compliance than contact lens and glasses Optically best as it induces the least anisometropia Faster visual rehabilitation Cosmetically best Excellent choice in mentally challenged children as it avoids compliance issues . 76

77. 77

78. Challenges In Pediatric Cataract Surgery Low scleral rigidity Increased elasticity of anterior capsule High vitreous pressure Small, soft and poorly developed eye Increase post-operative inflammation Changing refractive state Higher re-surgery rate Risk of amblyopia 78

79. Pediatric Vs. Adult Cataract surgery Small eyeball so difficult manipulation Poor pupil dilation Less scleral rigidity so more chance of wound leakage , collapse of anterior chamber and raised IOP during the surgery Use of highly cohesive viscoelastic Difficult capsulorrhexis Difficulties about IOL implantation Higher rate of PCO Amblyopia management 79

80. 80