Pakistan Journal of Ophthalmology Vol. 31, No. 1, Jan – Mar, 2015 1 Editorial Advanced Approaches for Management of Retinal Detachment Vitrectomy without scleral buckling1 for rhegmatogenous retinal detachment is often referred to as “primary vitrectomy”2; a term which at least initially implied that scleral buckling was the standard of care and should be tried before resorting to vitrectomy. This “rescue therapy” approach is considered to be “conservative” and applied in many specialties and disease processes but can produce the unintended consequence of delaying adoption of improved therapies and putting the patient through an unnecessary procedure. Anterior segment surgeons do not try intracapsular cataract extraction before resorting to phaco or RK before LASIK. Long bone fractures were not randomized to sham therapy after casts were developed. There are no high quality clinical trials comparing vitrectomy3,4, scleral buckling, and combined vit-buckle procedures for rhegmatogenous retinal detachment surgery because there are a high number of clinical variables and many treatment options which are often used in combination. Pre-operative variables include type of breaks, size of breaks, number of breaks, lens status, refractive error, vitreous hemorrhage, vitreous traction, family history, status of the other eye, medical status, and many others. Variables in scleral buckling include: hard silicone versus sponges, subretinal fluid drainage versus non-drainage, radial versus circumferential elements, encircling versus segmental buckles, use of air or gas, paracentesis and many others. Variables in vitrectomy include air, SF6, C3F8 or silicone oil, laser versus cryo, 20, 23, 25 or 27 gauge5, use of liquid perfluorocarbons, combined lensectomy6 or phacoemulsification, post-operative positioning, and many others. Scleral buckle advocates7 have stated that pneumatic retinopexy often causes PVR but they manage “fish-mouthing” in scleral buckling with gas injection; this is not rational. Some surgeons use vitrectomy only for pseudophakic eyes believing incorrectly that vitrectomy causes de novo nuclear sclerosis when, in fact, it only causes progression of pre-existing nuclear sclerosis because a permanent increase in the partial pressure of oxygen (12 mmHg). Complications of Scleral Buckling Proponents of scleral buckling often minimize the complications of scleral buckling7. And state that they “never” produce strabismus yet a high quality prospective trial reported by the late Ron Michels, an excellent surgeon, demonstrated a 50% incidence of increased tropias and phorias. Encircling buckles may result in damage to the superior oblique or superior rectus tendons producing problematic vertical strabismus. Fortunately, most buckle surgeons have given up the unnecessary practice of removing and reattaching extraocular muscles. Aggressive traction on retromuscle traction sutures, especially with small diameter sutures can damage and potentially sever intraocular muscle tendons. Aggressive stripping of the intramuscular septum, Tenon’s capsule, and episclera combined with cautery can create adhesions between these layers causing problems when there is subsequent glaucoma filtering procedures. Many surgeons use encircling bands7 in essentially all buckle cases. A circumferential buckle produces the same outcomes in most instances without inducing myopia or causing damage to extraocular muscles potentially causing diploplia or damage to the levator aponeurosis resulting in ptosis. Patients spend substantial sums of money in the pursuit of emmetropia; LASIK, PRK, and refractive lens exchange have raised patient’s expectations of life without glasses or contacts. Cataract surgery patients expect emmetropia as well; substantial effort has been applied to microincisional surgery, foldable IOLs, toric IOLs, multi-focal intraocular lenses, accommodative (minimally) IOLs, and femtosecond laser surgery. An encircling band produces 2.75 diopters of myopia on average; this is completely unacceptable to a patient that has paid for refractive cataract surgery, LASIK, or PRK. More serious complications of scleral buckling include late intrusion of the buckle and buckle extrusion and infection7. Intraoperative complications include a 5% incidence of retinal incarceration at the drainage site when using cut-down drainage as well STEVE CHARLES 2 Vol. 31, No. 1, Jan – Mar, 2015 Pakistan Journal of Ophthalmology as bleeding related to the drainage site. Scleral, choroidal, retinal perforation with scleral sutures is a not uncommon as well; sometimes with serious consequences. Vit-Buckles Many vitreoretinal surgeons use encircling bands in conjunction with vitrectomy for repair of rhegmatogenous retinal detachment; so called vit- buckles8. I have not used this approach for two decades in order to eliminate buckling induced refractive errors, strabismus, ptosis, and pain as well to reduce operating times and therefore labor costs. Patients would not want a vitreoretinal surgeon to use encircling bands when having vitrectomy repair of retinal detachment if they were informed about outcomes and complications. There is no level one evidence that vit-buckles produce better outcomes than vitrectomy without scleral buckles, even in PVR cases. Vitrectomy Techniques Wide-angle visualization techniques and/or scleral depression are essential if vitrectomy is to be used for retinal detachment repair.9 Contact-based wide-angle visualization (Volk, AVI) produces 10 degrees greater field of view than non-contact (BIOM, ReSight, Merlin and eliminates all corneal asphericity (keratoconus, LRI, RK, PK, cataract surgery, LASIK, PRK). In addition, contact-based wide-angle visualization greatly reduces the need for ocular rotation to view the periphery which reduces flexural forces on 25/27 gauge tools. Just as with scleral buckling, all retinal breaks must be identified and treated with retinopexy.10 Traction to the flap as well as vitreous traction surrounding all breaks must be eliminated to produce ~90% single procedure success rates. Internal drainage of subretinal fluid performed simultaneously with fluid-air exchange with a soft-tip cannula usually drains most of the subretinal fluid. If internal drainage is initiated prior to fluid-air exchange, posterior migration of subretinal fluid is reduced. Drainage retinotomy can be used if substantial posterior migration of subretinal fluid occurs or the retinal breaks are very small and far peripheral which can make internal drainage challenging. Another option for removal of subretinal fluid is perfluorocarbon liquids; N-perfluorooctane (PFO) is the preferred agent because the interface is visible unlike perflurodecalin. PFO will remove all subretinal fluid if the optimal techniques are utilized while internal drainage of subretinal fluid plus fluid-air exchange always leaves a thin layer of fluid which must be pumped out by the RPE. Because PFO causes subretinal fluid to float anteriorly, care must be taken to remove all SRF anterior to the retinal breaks to enable surrounding all breaks with endolaser. This can be done by extending the break to the ora or making a very peripheral, small drainage retinotomy but the best approach is to slowly drain SRF through the retinal break using a 25G soft-tip cannula just when the PFO reaches the break12. Care must be taken to not remove any PFO. The MedOne 25G dual-bore VFI is ideal to inject PFO while allowing infusion fluid egress to maintain optimal IOP. 25/27 Gauge Sutureless Vitrectomy The author utilizes 25/27G sutureless13 approach for all vitrectomies including rhegmatogenous retinal detachments, PVR, giant breaks, and diabetic traction retinal detachments. Just as today’s patients expect emmetropia without strabismus or ptosis as discussed above, they expect a painless procedure and a non- inflamed eye. A non-inflamed, pain-free eye is not achievable with 20G sutured wounds or vit-buckles. Contrary to what some surgeons believe, 25G vitrectomy fluidics are preferable to 23G or 20G fluidics for RD14 cases because port-based flow limiting due to a smaller lumen reduces pulsatile vitreoretinal traction. The author strongly recommends use of the highest possible cutting rate for all tasks and all cases; especially for giant breaks and other retinal detachment cases. The author uses the Alcon Constellation Vision System at 7500 cuts/minute. Sutured-on contact lenses damage the conjunctiva, cause sub-conjunctival bleeding, and are inappropriate for sutureless, trans-conjunctival surgery. Medium Term PFO for Inferior Retinal Detachments The author developed and has used medium term PFO for virtually all inferior retinal detachments including phakic and pseudo-phakic eyes, young myopes without PVDs, giant breaks and early PVR. Vitrectomy, PFO injection and laser is performed at the initial procedure; the PFO is removed at 14 days. The patients can sit, stand, work and fly; no bedrest is required. PFO is not toxic; it causes a reversible foreign body response in some patients with no long term sequela. Retained small bubbles in the anterior chamber must be removed with a 30 gauge needle at the slit lamp to prevent long term glaucoma. If PVD if ADVANCED APPROACHES FOR MANAGEMENT OF RETINAL DETACHMENT Pakistan Journal of Ophthalmology Vol. 31, No. 1, Jan – Mar, 2015 3 not present at the initial procedure, it will slowly and safely occur during the 14 days the PFO is in place. Silicone Oil Silicone oil injection is not difficult with the Alcon 25/27 gauge tools; there is no need for reverting to 20 or 23 gauge surgery for silicone oil cases. 1000 cS oil has the same emulsification rate as 5000 cS oil and is 5X faster to inject and remove; there is no need for 5000 cS oil. Oil should be injected with a short thin wall cannula after fluid air-exchange not through infusion cannula tubing system. Removal of oil is not necessary or advantageous for PVR re-operation or epimacular membrane; forceps membrane peeling with Alcon 25G DSP ILM forceps, retinectomy, removal of subretinal fluid an endophotocoagulation can all be performed handily “under” oil. Summary Sutureless, trans-conjunctival microincisional vitrectomy is ideal for retinal detachment repair. In the author’s opinion, vit-buckles are no longer indicated; the focus should be on microincisional vitrectomy techniques and wide-angle visualization to repair retinal detachments without causing pain, refractive error, strabismus, ptosis, cosmetic problems and longer, more costly operating times. REFERENCES 1. Goezinne F, La Heij EC, Berendschot TT, Kessels AG, Liem AT, Diederen RM, Hendrikse F. Acta Incidence of redetachment 6 months after scleral buckling surgery. Scleral Buckling versus Vitrectomy, Brazitikos P., Ophthalmology. 2006; 113: 1245. 2. Ho JD, Kuo NW, Tsai CY, Liou SW, Lin HC. Surgeon age and operative outcomes for primary rhegmatogenous retinal detachment: a 3-year nationwide population-based study. Ophthalmol. 2009; 23. 3. Von Fricken MA, Kunjukunju N, Weber C, Ko G. 25- Gauge sutureless vitrectomy versus 20-gauge vitrectomy for the repair of primary rhegmatogenous retinal detachment. Eye. 2009 May 1. 4. D'Amico DJ. Clinical practice. Primary retinal detachment. Retina. 2009; 29: 444-50. 5. Heimann H. [Primary 25- and 23-gauge vitrectomy in the treatment of rhegmatogenous retinal detachment-- advancement of surgical technique or erroneous trend?] N Engl J Med. 2008; 27: 359. 6. Acar N, Kapran Z, Altan T, Unver YB, Yurtsever S, Kucuksumer Y. Primary 25-gauge sutureless vitrectomy with oblique sclerotomies in pseudophakic retinal detachment. Retina. 2008; 28: 1075-81. 7. Hedaya J, Nigam N, Freeman WR. Scleral Buckling versus Vitrectomy. Retina. 2008; 28: 1068-74. 8. Miller DM, Riemann CD, Foster RE, Petersen MR. Primary repair of retinal detachment with 25-gauge pars plana vitrectomy. Ophthalmology. 2008; 115: 1634-5. 9. Lai MM, Ruby AJ, Sarrafizadeh R, Urban KE, Hassan TS, Drenser KA, Garretson BR. Repair of primary rhegmatogenous retinal detachment using 25-gauge transconjunctival sutureless vitrectomy. Retina. 2008; 28: 931-6. 10. Dubey AK, Dubey B. Primary 25-guage trans- conjunctival sutureless vitrectomy in pseudophakic retinal detachment. Retina. 2008; 28: 729-34. 11. Zhou P, Zhao MW, Li XX. Re: Phacovitrectomy for primary retinal detachment repair in presbyopes. Retina. 2008; 28: 666. 12. Mendrinos E, Dang-Burgener NP, Stangos AN, Sommerhalder J, Pournaras CJ. Primary vitrectomy without scleral buckling for pseudophakic rhegmatogenous retinal detachment. Retina. 2008; 28: 665. 13. Pastor JC, Fernández I, Rodríguez de la Rúa E, Coco R, Sanabria-Ruiz Colmenares MR, Sánchez-Chicharro D, Martinho R, Ruiz Moreno JM, García Arumi J, Suárez de Figueroa M, Giraldo A, Manzanas L. 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Steve Charles, MD FACS, FICS Clinical Professor of Ophthalmology University of Tennessee Founder & CEO, Charles Retina Institute www.charlesretina.com http://www.ncbi.nlm.nih.gov/pubmed/19432848?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum http://www.ncbi.nlm.nih.gov/pubmed/19432848?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum http://www.ncbi.nlm.nih.gov/pubmed/19432848?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum http://www.ncbi.nlm.nih.gov/pubmed/19407840?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum http://www.ncbi.nlm.nih.gov/pubmed/19407840?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum 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