This document discusses the history and evolution of iris clip intraocular lenses (IOLs). It describes generations of IOL designs from 1949 to present day. Key developments include Binkhorst's iris clip lens in 1965 and Worst's iris claw lens in 1978, which pioneered iris fixation without sutures. Modern iris clip IOLs are made of PMMA or foldable materials, have vaulted designs for clearance, and fixate to the iris periphery for unrestricted pupil function. They are indicated for lens implantation in cases of cataract or aphakia.

1. Step by Step Iris Clip
Dr Rahul Achlerkar
Dr Vijay Shetty

2. HISTORY
Italian scientist Tadini in mid 18th century first considered
intraocular lens implantation.
In 1895, Casamata implanted glass IOL which sank
posteriorly.
English ophthalmologist Sir Nicholas Harold Lloyd Ridley
is credited for first successful IOL implantation on November
29th 1949, at St. Thomas’ hospital in London.
Sir Harold Ridley (1906-2001)

3. EVOLUTION AND DEVELOPMENT
Generation-I (1949-1954)
 Biconvex PMMA PCIOL
 Implanted behind iris after ECCE
 Diameter – 8.32 mm; Power – 24 D
Complications:
•Inferior decentration
•Posterior dislocation
•Inflammation
•Secondary glaucoma

4. Generation-II (1952-1962)
 Early Anterior Chamber IOLs
 Fixation of lens in angle recess
 Advantages:
 Less decenteration
 Decreased reaction
Complications:
•Corneal decompensation
•Pseudophakic Bullous keratopathy
•Uveitis
•Secondary glaucoma
•UGH syndrome
EVOLUTION AND DEVELOPMENT

5. Generation-III (1953 – 1975)
 Iris supported or iris fixated IOLs
 Advantages:
 It is away from angle structures hence
rate of complications like secondary
glaucoma is less.
 Rate of dislocation is less.
 Less contact with corneal endothelium
hence lesser damage to it.
•Complications:
•Iris chaffing
•Pupillary distortion
•Chronic inflammation
•CME
•Distortion on pupillary dilatation
•Endothelial decompensation
EVOLUTION AND DEVELOPMENT

6. Why the Iris?
 Iris is the ”toughest” tissue within the eye
 The iris is a resilient tissue.
 Pigmented tissue in nature is usually associated with being “tough”

7. Iris
Macroscopic appearance.
1. Ciliary zone.
It presents series of radial streaks
due to underlying radial blood
vessels
2. Pupillary zone.
 Is relatively smooth and flat.

8. The Iris consists of
Pupil Border
 The sphincter mechanism of the
pupil border is functioning due to a
smooth muscle with a great
constricting and dilating capacity.

9. Anatomy of the Iris
 The stroma connects to a sphincter muscle (sphincter pupillae)
 It contracts the pupil in a circular motion, and a set of dilator muscles
(dilator pupillae) which pull the iris radially to enlarge the pupil, pulling it
in folds.

10. Anatomy of the Iris
Sphicnter pupillae muscle Dilator pupillae muscle

11. Pupil Dilatation Mechanism (3 concentric
areas)
 The central part is highly mobile dilatable and constrictable
 The paracentral thickened area lies at two-third from the iris
base
 The iris base is immobile.

12.  Binkhorst’s (1965)-
 Iridocapsular Lens
 Posterior haptics in capsular bag with anterior
loops removed.
 In 1970 Binkhorst and Worst employed a trans-
iridectomy suture for fixation mechanism-
MEDALLION lens.
EVOLUTION AND DEVELOPMENT

13. EVOLUTION AND DEVELOPMENT
Iris clip lens (Binkhorst) Iris claw lens( Worst)

14. Discovery of the Iris Claw principle
 Using an early model, the Slotted Medallion lens, Jan Worst
sometimes observed that some iris tissue was caught in the slot
of his lens.
 This clasping of iris tissue proved to be a serendipitously
discovered new possibility for stable fixation of the IOL.
 Once the efficacy of this additional fixation method had been
proven in a number of cases additional iris stitching seemed no
longer necessary.

15. Peripheral Iris Supported IOLs
 The design was relatively
simple
 One piece, one material,
without additional loops.
 The fixation mechanism is
based on the enclavation of a
fold of iris tissue.

16.  In 1997 an improved vaulted design of the ARTISAN®
Aphakia Lens was introduced with a number of new
characteristics.
 The lens configuration was made vaulted to create distance to
the iris
 Enclavation was made easier by using a lens with a larger and
oval aperture between optic and haptics than the original
circular shape.

17. Worst Iris Claw® IOL (left)
ARTISAN®/ Iocare Aphakia IOL

18. Lens Design
 “Iris Bridge” support
 The fixation points of these
lenses are located in the
virtually immobile part of
the peripheral iris
 The “iris bridges” form a
shield and protect the cornea
from touching the PMMA
haptics of the IOL.
The Iocare /ARTISAN® Aphakia IOL

19.  Since the start of the original design of the Iris Claw lens
(1978), the fixation concept of this lens has remained
unchanged
 Only the lens design has slightly changed in 1997 (vaulted
design and oval aperture).

20. Worst Iris Claw design
Vaulted IoCare/ ARTISAN® design

21. Unrestricted dilatation
 The haptics (fixation arms) attach to the midperipheral virtually
immobile iris stroma, thus allowing the pupil unrestricted
ability to dilate &constrict
 Fluorescein angiographic studies by Strobel1 and Izak2 have
shown no leakage of the iris vessels at the enclavation sites.
 Only a few cases of iris atrophy in the area of the fixation have
been reported in the literature

22. Unrestricted dilatation

23. Lens Manufacturing
 Compression Molding Technology
During the compression molding process the molecular
structure of PMMA is enhanced by redistributing the molecules
into longer chains, resulting in a much stronger material.

24. Compression Molding Technology
PMMA before and after compression
molding.

25. Extreme flexibility of the haptics
 Compression Molding Technology gives a high tensile
strength, combined with flexibility of the lens haptics.
 The risk of fracture is minimal.
Proprietary Tumbling Process
 The proprietary tumbling process gives a special surface
treatment to IOLs.
 An ultra smoothness of the IOL is the result.

26. Technical Specifications
 Lens type: AC/ PC Iris
Fixation (“ Iris Bridge”)
 Lens material: Perspex-CQ
UV
 Fixation: Mid-Peripheral,
 Iris Stromal Support
 Overall diameter: 8.5 mm
 Body diameter: 5.4 mm

27. Technical Specifications
 Optic diameter: 5.0 mm
 Total height: 0.76 mm
 Weight: 8mg in air (20D
lens)
 Sterilisation: Ethylene
oxide
 AC Depth: 3.3 mm
 A-constant: 115.0
(Ultrasound)
 115.7 (Optical)

30.  Powers available: +2.0 D to
+30.0 D (1.0 D increments)
 +14.5 D to +24.5 D (0.5 D
increments).

31. Versatility AC or PC fixation

32. Paediatric Aphakia IOL
 Lens type: AC Iris Fixation
(“Iris bridge”);
 Lens material: Perspex-CQ
UV;
 Overall diameter: 6.5 mm;
 Body diameter: 4.4 mm;
 Optic diameter: 4.4 mm;
 Total height: 0.56 mm;
 Weight: 8mg in air (20D
lens);
- 6.5mm overall size

33. Benefits
 The “iris bridge” protects the
endothelium from touching the
PMMA
 Safe clearance from vital
structures (corneal endothelium);
 Unrestricted pupil dilatation and
constriction (sphincter
independent)
 Excellent centration; once fixated
the lens will not decenter
“vaulted” lens configuration

34. Iris clip Angle Supported
lens
Sclera sutured PC
IOL
Safety Excellent,
predictable
Angle related
complications
Sutures can erode
and
refraction unstable
Outcomes Excellent,
predictable
Angle related
complications
Refraction not
predictable,
lens tilt,
hemorrhage and
secondary glaucoma
Clinical History 30+ years Removed from
many
markets
30+ years
Toric option Yes No No
Suturing
required IOL
No No Yes
Fixation options Iris Angle Sclera, sulcus, iris

35. Next Generation of Iris Fixated IOLs
 Foldable lens body thus
permitting a small incision.
 Small incision, 3.2 mm
 Controlled folding and
unfolding
 Reversible treatment
 Aspherical edge design
 Large optical zone

36. Toric iris clip IOLs
PMMA
Optic –Polysiloxane
Haptic-PMMA

39. Other Indications
 Iris fixated Custom-made IOLs include lenses for the
treatment of unique ocular conditions like
 Coloboma,
 Diplopia
 There are two categories of Custom-made lenses:
 Iris Reconstruction IOLs (made of coloured & clear PMMA)
 Pupil Occluder for Diplopia Correction (made of black
PMMA).

40. Iris fixated Reconstruction IOLs
 IOLs with coloured haptics (blue, brown, green or black) are
ideal for anterior segment reconstruction when iris damage has
occurred or is already congenitally present.
 Even large iris colobomata can be covered by the coloured
haptic of the IOL.

42. Pupil Occluder for Correction of
Diplopia
 Another application of the iris base Fixation Concept is Pupil
Occlusion in case of intolerable Diplopia due to ocular muscle
imbalance.
 The Pupil Occluder functions as a cover over the pupil to
prevent double images.
 Occluder is made of black polycarbonate and covers the pupil
completely
 Due to the vaulted configuration it can be applied in both
phakic and aphakic eyes

43. 8.5mm overall size Pupil Occluder in situ

44. The main features are:
 Minimal risk surgery
 The anatomy of the iris and its specific features allow surgery
with minimal risks. Fixation is performed to the iris periphery.
 Pressure free iris fixation
 No iris atrophy when the recommended surgical technique is
used

45. indications
 Senile cataract with severe zonular dialysis
 Traumatic cataract
 Congenital or juvenile cataract with subluxation
 Secondary implantation after aphakia.

46. Contraindications
 Recurrent or chronic iritis
 Rubella cataract
 Retina and optic nerve defects;
 Corneal distrophy (except in preparation for penetrating
keratoplasty)
 Acute inflammation
 Severe iris atrophy
 Uncontrolled chronic glaucoma

47. Technique for AC iris fixated iol

50. Video of AC iris clip IOL

51. Enclavation Forceps
Enclavation Needle

52. Foldable Iris clip
Perform a main
incision of 3.2 mm Insertion Spatula

53. How to properly Enclavate the iris
Notice that the “claws” are perfectly aligned.

54. PROPER technique

55. WRONG technique

56. See damage caused by improper
enclavation

57. Peripheral iridectomy or iridotomy
 Although all Aphakia IOLs are vaulted ,it is highly
recommended to perform an iridectomy or iridotomy.
 The pigment layer needs to be perforated completely
 An iridectomy or iridotomy has to be made to avoid a postop
pupil block
 It can also be used to manage an unwanted iris prolapse.

58. Retropupillary Fixation Technique
 As recommended by A. Mohr, M.D.
 A technique is recommended with a 12 o’clock frown incision
(corneo-scleral 5.5mm)
 Authors from Bursa-Turkey use a scleral tunnel incision to
avoid the formation of postoperative astigmatism.
 The width of the incision should be 5.5 mm.

59. Do not constrict the pupil
 Leave the pupil at a minimum size of approximately 3mm to
allow the lens to reach the retropupillary position through the
pupil.
use of high viscosity viscoelastic
 Inject a small amount of viscoelastic from the periphery of the
eye, but never directly into the pupillary area

60. Implantation of the iol
 The IOL will be inserted into the anterior chamber with the
convex side downwards (upside down) holding it in the
forceps.
 With a manipulator, the IOL will be brought into the horizontal
position from 3 o’clock to 9 o’clock.

61. iol fixation on the iris
 After the IOL has been brought behind the iris and the pupil is
constricted, the IOL will be lifted and tilted slightly in order to
show the contour of the“claws” through the iris stroma.
 A fine spatula is inserted and exerts gentle pressure on the
slotted centre of the lens haptic, the “claw”.
 The same manoeuvre is now repeated on the other side.
 The IOL is now retropupillary fixated.

62. VIDEO OF RETROFIXTED IRIS
CLIP

63. Peripheral iridectomy
 It is not absolutely essential and strictly recommended to
perform an iridectomy
 removal of all viscoelastic
Carefully remove all of the viscoelastic to avoid a high pressure.
 Suturing
Close the incision with sutures.

64. VIDEO PUPILOPLATY

65. INTRA operative problems
Macular burns
 The light of the surgical
microscope may cause
damage to the macula during
surgery
Prevention
 Use a protecting filter on the
microscope or cover the
pupil with a surgical sponge
.

66. Iris Prolapse
 An iris prolapse occurs more
often when making a
corneoscleral incision, than
making a tunnel incision
Prevention
 Place one or two sutures
after the insertion of the lens
and before the enclavation.
Solution
 Make an iridectomy as soon
as possible.

67. Lens not centered properly
 A decentered IOL may cause
glare or halos
Prevention
 Check the centration of the
IOL on the pupil after
removal of the viscoelastic.
Solution
 It can be corrected by re-
enclavation

68. Insufficient Iris Enclavation
 Insufficient Iris Enclavation
can lead to postoperative
dislocation
Prevention
 Use the specific instruments
developed for the Aphakia
IOL implantation
Solution
 Re-enclavate a dislocated
IOL

69. Subluxation
 After ocular trauma or spontaneously, luxation of one of the
claws can occur, leading to subluxation of the IOL
 when a too small amount of iris tissue is enclavated, The IOL
has to be reenclavated
 immediately to minimize endothelial damage.

70. Secondary surgical interventions
Lens repositioning
 Is necessary after lens decentration and in cases in which a
preventive repositioning was performed
 in subjects with too small amounts of enclavated iris tissue.
Lens replacement
 An IOL can be removed and replaced by a new Aphakia IOL.

71. Articles of Interest
Long-term follow-up of the corneal endothelium after
artisan lens implantation for unilateral traumatic and
unilateral congenital cataract in children: two case
series.
Odenthal MT, Sminia ML, Prick LJ, Gortzak-Moorstein N, Volker -Dieben HJ. Cornea 2006;
25(10):1173-7.
RESULTS: Endothelial cell loss 10.5 yrs after iris fixated IOL
implantation for traumatic cataract was substantial & related to the
length corneal scar of original trauma . In children operated for
congenital cataract , no difference was found in CECD in operated &
unoperated eyes after 9.5 yrs after artisan iols

72.  Penetrating keratoplasty combined with
posterior Artisan iris-fixated intraocular lens
Implantation
Dighiero P, Guigou S, Mercie M, Briat B, Ellies P, Gicquel JJ. Acta Ophthalmol
Scand. 2006; 84(2):197-200

73. Dr Vijay Shetty
Dr Suhas Haldipurkar
Dr Shweta Rao
Dr Maninder Singh Setia
A RETROSPECTIVE ANALYSIS OF IOL POWER
CALCULATION AND POSTOPERATIVE RESULTS OF
IRIS CLIP IOL
WOC 2011
Abu Dhabi

74. AIM
• To study the post operative visual outcome in retrofixed
iris clip IOLs with respect to uncorrected visual acuity and
best corrected visual acuity
• To study the refractive outcome in iris clip IOLs using IOL
master and various formulae
• To study the prevalance of PXF, Trauma, Marfan’s
syndrome, retinal tears, cystoids macular oedema and
retinal detachment in patients who underwent iris clip
IOL

75. CONCLUSION
 Retrofixed iris clip IOL is a relatively a safe procedure in
eyes with no capsular support. Trauma, PXF and Marfan’s
syndrome were associated in 41%, 14% and 14%
respectively .IOL was required in 5/26 (19%). Similar IOL
refixation was noted in both horizontal and vertical
fixation.CME: 2/26, Uveitis: 1/27, Retinal Hole: 1/27 in our
population,
 Hoffer Q formula predicted the IOL power most
accurately for iris clip IOLs consistently in eyes with
varied axial length followed by Holladay and SRK T.

76. Books
 1. Cataract and IOL
Daljit Singh, Jan Worst, Ravijit Singh, Indu R. Singh. 1993
Chapter 20: Iris Claw Lens, page 82-97
 2. A Colour Atlas of Lens Implantation
Chapter 13: Iris-fixated lenses, evolution and application – Jan
Worst, page 79-87
 3. Iris Claw Lens or Lobster Claw Lens of Worst
Alpar JJ / Fechner PV, 1986