1. Phacoemulsification some Basic Ideas… Khalid M. Al-Arfaj, MD Dammam University

2. 3-Vedio … 1-Quiz … 2- lecture …

3. Case selection … Anesthesia …

4. Antibiotics Control blepharitis well before surgery (endophthalmitis usually results from lid flora)! Fluoroquinolones Povidone-iodine inexpensive extremely broad-spectrum irritating to eye in undiluted (10%) solution; dilute to 5% irrigate fornices with solution paint, do not scrub, eyelashes when prepping Pre-operative Eyedrops

5. History of small incisions 1977: Scleral tunnel 1990: Sclerocorneal 1991: Clear corneal 1991-present: Variations in clear corneal

6. Conjunctival peritomy Dissection through Tenon’s fascia Cautery Scleral groove 1-2 mm posterior to the limbus Scleral tunnel Keratome to enter the AC

7. Advantages: Wound can be safely enlarged for conversion to ECCE Conjunctiva covers the wound Potentially less endothelial damage Astigmatically neutral

8. Disdvantages: Surgical exposure Sunken eyeball Prominent brow Potential damage to ciliary body Iris prolapse Filtering blebs and scarring make it difficult

9. Keratome to tunnel and enter the eye. Clear cornea

10. Advantages: Can use topical anesthesia Faster Better surgical exposure Filtering blebs and scarring irrelevant No subconjunctival hemorrhages

11. Disadvantages: Pre-existing corneal problems a relative contraindication: Fuchs Previous PK Possible higher rate of endophthalmitis in unsutured cases Ballooning of conjunctiva if incision too posterior Conversion to ECCE more problematic

12. Astigmatism Pre-existing ocular disease: Pterygia Filtering blebs Tubes Endothelial disease Wound location

13. Tunnel length Goal to be self-sealing “Square” incision Depends on width Generally want at least 2.0-2.5 mm long Sharp entry through Descemet’s membrane Wound architecture

14. External incision Too anterior or too posterior Internal incision Too anterior or too posterior Tunnel Too long or too short Incision width Too narrow or too wide Problems with the wound

16. Wound Final Thoughts The wound may be one of the easiest steps of cataract surgery, but it sets the stage for the entire case Everyone may have a different phaco wound Principles the same

17. Capsulorrhexis Continuous curvilinear capsulorrhexis (CCC) It is a continuous tear capsulotomy. It can be made in the anterior capsule or both anterior and posterior capsules. It confines the IOL to the capsular bag. It assures long-term centration of the IOL.

18. Technique Completely fill the anterior chamber with viscoelastic agent. Flatten the dome of the anterior lens capsule Puncture the anterior capsule with a bent 30-gauge needle or sharp-tipped capsulorhexis forceps. Start a flap that flops over toward the incision.

19. Technique Grasp the flap with capsulorrhexis forceps (Utrata forceps). Spiral out to the desired diameter. Tear tangentially all the way around (no radial forces). Regrasp the flap as necessary. Keep an equal distance from the pupil margin while tearing.

20. Hydrodissection & Hydrodelineation Goals Nucleus rotation Epinucleus rotation Loosen cortex

21. Used to separate lens nucleus from surrounding cortex and capsule Creates a freely mobile nucleus Facilitates nucleus rotation during phacoemulsification Hydrodissection

22. Used to separate epinucleus from harder nuclear material Creates an epinuclear bowl that protects lens capsule during phacoemulsification Hydrodelineation

23. Hydrodissection cannula 25- to 30- gauge Flattened tip with angled or curved shaft Facilitates placement under anterior capsule J-shaped cannula may be used for sub-incisional area Background Technique …

24. Complete several fluid waves to ensure adhesions to capsule broken Proceed to hydrodelineation Inject fluid into edge of nucleus “ Golden ring ” sign indicates epinuclear separation Confirm that nucleus rotates

25. Lens nucleus occludes capsulorhexis Trapped BSS expands posterior capsule, AC shallows Posterior capsule may rupture Intraoperative Capsular Block Syndrome

26. PHACODYNAMICS

27. Two Basic Elements US → Emulsify the Cataract Fluid circuit → cooling and remove the Emulsified Cataract

28. Three Main Machine Functions US Flow Irrigation

29. Fluidics Irrigation Flow Vacuum

30. Fluidics Flow → peristaltic → vacuum only at occlusion Vacuum → venture → continuous vacum BOTH → millennium Flow control mode Vacuum control mode Type of Pumps

31. Irrigation Amount of fluid that enters the eye Depend on:  Bottle height  pressure on the eye  flow from the eye Tip diameter Wound leak

32. Flow Fluid leaving the eye ml/min Speed with which the material is sucked to the tip Control pump speed No-occlusion → current and attraction force With occlusion → rise time (time for maximum preset vacum) Flow rate Surge Vacum rise Safety

33. Vacuum Holding power With occlusion → No flow but pump will continue → negative pressure at aspiration line → vacum → Stop pump at maximum preset vacum

34. Good Fluidics Irrigation Wound Leak Aspiration (flow) Vacum

36. Surge Sudden ↓ of A/C pressure → collapse Dynamic ↓ of vacum by surgeon by deocclusion Bottle height Machine compliance Vacum and flow rate Tip diameter → resistance

37. Flow Flow depends on pump speed not on bottle height

38. US Power mode of delivery

40. US Safest phaco is with appropriate power not with the lower power

41. Mechanism of Action Jackhammer → direct contact Cavitation → with cavitational bubbles Sonic wave

42. Mode = US Delivery Continuous Pulse Burst

43. Pulse Fixed interval but linear power Fixed duty cycle

45. Burst Mode Fixed power of linear interval Variable duty cycle

48. Repulsion Chatter → flaying of peace away from the PHACO tip Mode - ↓ by Pulse, Burst and WS