The Dying art of the cryo buckle for retinal detachment surgery.pptx

Most surgery for retinal detachment is now performed with vitrectomy. There are however a limited number of patients in whom vitrectomy surgery is relatively contraindicated. The technical skills of many vitreoretinal surgeons in performing cryo buckling surgery is reducing due to limited exposure to this form of surgery especially in the UK where vitrectomy surgery is the primary form of retinal detachment operation. This presentation shows useful tips and pearls on how to perform a cryo buckle procedure and when it is indicated

1. The dying art of the cryo buckle Peter Simcock William Yan West of England Eye Unit, Exeter, UK

2. Timeline of the scleral buckle Gonin - ‘Detachments do not cause tears.. and are treatable’ Pre-1935: Retinal tears are caused by detachments Scleral ‘buckle’ or ‘indent’ first described by scleral resection Resection was replaced by polyviol explant ( Custodis , 1949) and scleral coagulation Schepens and Pruett, 1951 refined technique with circular buckle + SRF drain Lincoff and Kreissig developed scleral sponge and demonstrated retinal adhesion by cryotherapy in rabbits 1972 Kreissig in Bonn begins routine repair of RDs with scleral sponge buckle and cryotherapy to breaks, without SRF drainage Modern technique of scleral buckling teaching begins out of Kreissig group in Bonn, Germany

3. What detachment patients are suitable for vitrectomy in 2025? Nearly all patients Presence of PVD is very important Ease of vitrectomy directly related to vitreous syneresis and separation In general, presbyopic patients are good candidates as subsequent cataract surgery will not be an issue and the gel is syneretic Young patients with formed, attached gel – not good candidates

4. Do we need to do cryo buckles? - yes Young patients with formed, firmly attached vitreous Pathology slowly progressive as the formed vitreous slows the spread of SRF both due to limited liquified vitreous and the remaining formed vitreous acting as a tamponade Retinal Dialysis - easy High myopia with slowly progressing RD from atrophic holes – difficult Inferior tears ? – less of a problem

5. Retinal dialysis Trauma related with forces transmitted thought the vitreous base Disinsertion of the retina at the ora serrata Vitreous base often still attached to retina posterior to the tear (unlike giant retinal tears) Inferotemporal quadrant 8 to 15% of retinal detachments

6. Lattice degeneration Abnormal vitreoretinal adhesion around the edges of lattice Frequent Acute PVD related with tear at edge of lattice Treat with vitrectomy Atrophic holes within the lattice degeneration Infrequent Not PVD related Chronic and slowly progressing May be high water marks Often high myopia and younger patients Treat with buckle

7. What does the buckle do? To reduce vitreous traction on the retina – yes Physically approximates the break in the neuroretina to the RPE To physically close a retinal break - no Does not have to be completely closed Changes in fluid dynamics can allow break to “settle” on the indent

8. What is the downside of the cryo buckle? Don’t do it very often – de-skilled Don’t like doing it – small gauge vitrectomy neat and clean Have to suture – get myself tied up in knots Back and neck ache Now presbyopic and cannot see what I am doing Struggle to drain SRF Get sub retinal haemorrhage when drains SRF More back and neck ache

9. The dying art of indirect ophthalmoscopy? We rarely do this in clinic Indentation painful Look at Optos images Wide field lenses used with slit lamp When do I do it? – bilateral PRP in diabetics under GA Chandelier systems – the game changer in cryo buckle surgery

10. What is the downside of the 29g chandelier system? Can only see the benefits! It does make it an intraocular procedure (if no SRF drainage needed) Risk of infection with such small gauge instrument very low Can remain seated at the microscope

11. Chandelier-assisted scleral buckle 2024 study Study Summary Meta-analysis of 33 studies with 1130 eyes 30% shorter surgery with chandelier (77 min vs. 96 min) 91.7% primary anatomical success, no statistical difference vs. standard external buckle technique No statistically significant difference pseudophakic vs. phakic in primary anatomical re-attachment endpoint No cases endophthalmitis reported

12. Decision time Vitrectomy or chandelier buckle? No need for pre-op indentation as do internal search Conventional buckle? Detailed pre op examination with indirect ophthalmoscopy with indentation Triple mirror contact lens exam If you miss a single small break – the operation will fail

13. Concerns with vitrectomy Inadvertent retinectomy Retinal incarceration in entry site Entry site break Cataract formation BUT Reduced with high speed, small gauge systems Most patients have presbyopia Cataract surgery very successful

14. Concerns with buckle Inadvertent deep suture with SRF release +/- subretinal haem especially if thin sclera Ocular motility restriction with diplopia Change in refraction Vortex vein compression with choroidal effusion

15. Concerns with encirclement of the eye Support vitreous base Often multiple small breaks at posterior border of vitreous base in aphakia and pseudophakia If too tight Anterior segment ischaemia / band pain Ocular motility issues Retinal folds If too loose No indent and does not work If too far back or too far forward No support of the vitreous base

16. Segmental buckles Radial Sponge Tear between muscles Needs accurate localization of break Circumferential Multiple tears Less accurate localization but redundant folds More prone to diplopia if underneath rectus muscle

17. Concerns with external sub-retinal fluid drainage Do you have to drain? Needle drain if watery SRF Laser drain with cut down if viscous SRF Complications Haemorrhage Retinal incarceration Avoid hypotony (hypotony = haemorrhage) Pre-place sutures and tighten buckle or encirclement Have air injection at the ready (on 30 g needle) but last resort as formed gel

18. Problems with high myopes Thin sclera Increased haemorrhage risk Increased choroidal effusion risk

19. Movement towards vitrectomy surgery Retinal detachment surgery in district general hospitals: an audit of changing practice. Ling R, James C, Simcock P, Gray R, Shaw Br J Ophthalmol . 2002 Jul;86(7):827-9. 85% Primary reattachment rate 58% Had vitrectomy

20. Is it time to call time on the scleral buckle? Br J Ophthalmol . 2004 Nov;88(11):1357-9 Editorial by Prof David McLeod 2 papers ( Moorfields and St Thomas’) on vity gas without buckle for retinal detachment with inferior retinal breaks Primary reattachment rate 89% and 81%

21. Inferior breaks and support with buckle Gas gives better tamponade to superior breaks Large inferior breaks need support with buckle? Large inferior buckles often difficult to place Increased complications with larger buckles Inferior PVR needs support with buckle? Other options Do vity peel or retinectomy and oil Subsequent oil removal +/- cataract surgery

22. Phacovitrectomy for Primary Retinal Detachment Repair in Presbyopes Retina 27(4):p462-467, April 2007 M Smith, S Raman, G Pappas, P Simcock, R Ling 93 patients having combined Phaco vity for primary RD Re-attachment rate 88.2% Fibrinous uveitis 16.2% Iris capture 8.6% No longer do combined phaco vity for retinal detachment!

23. Use of the operating microscope for scleral buckling Eye 2007 21, 103-104. V Raman, S Smith, P Simcock 377 patients 2 patients 0.53% had inadvertent scleral perforation by VR fellow Previous studies have suggested rate is up to 6%

24. Use of the operating microscope for scleral buckling Variable magnification Just enough to get the “job done” Over magnification = reduced depth perception Constant illumination Excellent visualization Better assessment of depth of needle pass through sclera Better recognition of surgical anatomy and tissue planes Better posture, sitting upright and stays in one position Better for teaching as assistant looks though teaching arm of microscope Good for presbyopia!

25. Use of the operating microscope for scleral buckling - tips 200mm objective on microscope Try and open the conjunctiva and Tenon’s with the same cut so straight into the sub-Tenon’s space Tissue plane is a few mm back from corneal limbus and preserves limbal stem cells Get a good right angle between the circumferential and radial conjunctival cuts Consider an 8/0 marker suture at this right angle

26. Use of the operating microscope for scleral buckling - tips Clip two adjacent black silk muscle traction sutures to head drape whilst assistant retracts the conjunctiva Surgeon then has both hands available for surgical manipulations Holding muscle insertion with forceps in non dominant hand improves proprioceptive input to dominant hand when placing the suture in the sclera Must develop ambidexterity and pass sutures forehand and backhand

27. Use of the operating microscope for scleral buckling - tips Blunt dissection is key to opening the tissue planes between the muscles Pass curved scissors closed into space between muscle insertions then open them wide to separate the tissue planes Do not worry about small bleeds, they will stop especially if you are only using blunt dissection Cutting tissue with scissors increases the risk of significant bleeding that needs diathermy

28. Use of the operating microscope for scleral buckling - tips Look for clues for muscle insertion position – anterior ciliary vessels Tenon’s and check ligaments are white, clean only amount required to place black silk traction suture and buckle Clean muscle with further blunt dissection (grasp check ligaments with forceps and pull back or brush tissue back with cotton bud) Do not go too for back with your squint hook, you should ideally already see the muscle insertion. Its not a “luck dip” or you can be unlucky and pull up an oblique muscle or damage a vortex vein

29. Use of the operating microscope for scleral buckling - tips Only sling all 4 muscles if doing an encirclement Do horizontal recti first so can rotate the eye up and down to expose the vertical recti Do the superior rectus last. Its furthest back Take care with superior rectus and make sure you have not caught the superior oblique. Sequential squints hooks from each side can help

30. Use of the operating microscope for scleral buckling - tips SRF drainage Find a site with deep SRF Try “prang drain” with 5/0 Ethibond needle Must keep the pressure up Tighten pre-placed sutures on buckling elements Have air to inflate the eye on a 30g needle (but care if formed vitreous)

31. Suture placement for circumferential buckle Many different options – my technique (from Prof McLeod) Posterior suture – circumferential orientation Operating microscope facilitates this as this is a relatively long pass through the sclera Just keep needle tip visible under the scleral fibers. If it disappears its too deep Keep the needle flat to the sclera as it’s a spatulate needle and do not pull the needle up until you are out of the sclera otherwise the back end of the needle can push on the choroid causing haemorrhage Do this suture first Anterior suture – anteroposterior orientation The wider the distance between the anterior and posterior sutures, the greater the indent

32. Tying the sutures 2, 2, 1 with 5/0 Ethibond Get the assistant to press on the buckle to create the indent, then take up the slack with the sutures Do not pull on the sutures to tighten the indent, there is risk of them pulling out especially if thin sclera Always check the patency of the CRAO after tightening the sutures Always have an AC paracentesis needle available if the CRAO is occluded

33. Closing the wounds Do a 2-layer closure with 8/0 Vicryl Make sure Tenon’s covers the edges of the buckle (reduces extrusion) Take care with the conjunctiva Marker sutures are invaluable in recognizing what goes where after extensive surgery Sometimes limbal sutures are needed to prevent conjunctival hooding over the cornea or to take up “stretched” conjunctiva

34. Resuscitating the cryo buckle Limited opportunity for exposure to this sort of surgery Wet lab / Simulator experience helpful Practice tying knots and placing sutures (done less and less) Microsurgical courses Use the microscope for your cryo buckles (even if you are not presbyopic ) A well performed cryo buckle in a young patient is a thing of beauty!