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base contraction at the ends of the giant tear and on the opposite side of the eye that cannot be fully relieved or that recur. A lensectomy is performed in phakic eyes with giant tears and PVR, unless there is no anterior component to the epiretinal proliferation. After lensectomy, a complete anterior vitrectomy is performed, with excision of as much tissue in the region of the vitreous base as possible. Meticulous removal of all epiretinal membranes is then performed in a posterior- to-anterior direction to make the retina as mobile as possible. This may be facilitated by injecting a small bubble of perfluorocarbon liquid on the posterior retina to partially reposition it and facilitate identification of epiretinal membranes for easier removal.
Subretinal scar tissue on the exposed outer surface of the retinal flap is also removed to increase the mobility of the retinal flap so that it can be unfolded into a more peripheral location. However, the flap may occasionally remain stiff and infolded, and in some cases excision of the peripheral part of the posterior retinal flap with the vitrectomy cutter is necessary to allow retinal flattening.
RESULTS OF VITRECTOMY
Results of vitrectomy for retinal detachment vary considerably, depending upon case selection. Durable retinal reattachment following vitrectomy for routine retinal detachments ranges from 65% to 100% in various reports, and averages approximately 85%, a figure that is quite comparable to that expected in scleral buckling surgery. One recent prospective randomized, controlled trial comparing these techniques has been performed. However, the results were quite complex and inconsistent with some additional non-controlled data.
Visual results are comparable to those seen following anatomically successful surgery with scleral buckling or pneumatic retinopexy, with the vast majority of patients with macula-off detachments experiencing a significant improvement in vision. Of the multiple factors impacting postoperative vision, preoperative vision is the most important, and ideal trials comparing the postoperative vision obtained with various techniques have not been performed.
COMPLICATIONS OF VITRECTOMY
In phakic eyes, the most important and common complication is that of progressive nuclear sclerosis; this can be expected to occur in the vast majority of cases. Importantly, the complications of altered refractive error and strabismus are quite unusual following vitreous surgery, with the exception of nuclear-sclerotic-induced myopia. Scleral perforation with a suture needle, complications of external subretinal fluid drainage and intravitreal gas injections, fish-mouthing of retinal breaks, and of course implant extrusion (all potential problems with scleral buckling) also do not generally occur with vitrectomy. Increased intraocular pressure, endophthalmitis, PVR, epimacular proliferation, recurrent retinal detachment, and choroidal
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detachment all may occur with vitrectomy as well as with scleral buckling. These complications are discussed in Chapter 7.
The most important causes of anatomical failure following retinal reattachment surgery are iatrogenic retinal breaks, new breaks, missed breaks, and PVR. The latter three problems can also be considered to be complications of the disease process that caused retinal detachment. By far the most serious of these is PVR. Severe PVR following vitreous surgery is more likely to feature a serious anterior loop component than PVR after a scleral buckle or pneumatic procedure.
SUMMARY
Vitrectomy techniques represent an elegant means of repairing retinal detachments, and are increasingly employed in the management of routine retinal detachments, particularly nonphakic cases. They are invaluable in the repair of complicated detachment cases, and with microincisional techniques they represent a lowimpact method for treatment of less complicated cases. The procedure features endoillumination, high magnification, wide-angle viewing, and vitreous cutting abilities to allow removal of opacities and membranes, unfolding of giant tears, and intraoperative retinal reattachment with the help of gas or perfluorocarbon liquids. Postoperative intraocular tamponade with a total gas fill or with silicone oil is made possible with vitrectomy techniques. Cataracts frequently develop following vitrectomy in phakic eyes.
SELECTED REFERENCES
Ah-Fat FG, Sharma MC, Majid MA et al.: Trends in vitreoretinal surgery at a tertiary referral centre: 1987 to 1996. Br J Ophthalmol 1999;83:396–398.
American Academy of Ophthalmology: The repair of rhegmatogenous retinal detachments. Ophthalmology 1990;97:1562–1572.
Brazitikos PD: The expanding role of primary pars plana vitrectomy in the treatment of rhegmatogenous noncomplicated retinal detachment. Semin Ophthalmol 2000;15: 65–77.
Brazitikos PD, Androudi S, D’Amico DJ et al.: Perf uorocarbonl liquid utilization in primary vitrectomy repair of retinal detachment with multiple breaks. Retina 2003;23:615–621.
Brazitikos PD, D’Amico DJ, Tsinopoulos IT et al.: Primary vitrectomy with perfluoro- n-octane use in the treatment of pseudophakic retinal detachment with undetected retinal breaks. Retina 1999;19:103–109.
Campo RV, Sipperley JO, Sneed SR et al.: Pars plana vitrectomy without scleral buckle for pseudophakic retinal detachments. Ophthalmology 1999;106:1811–1815.
Chang S: Low viscosity liquid fluorochemicals in vitreous surgery. Am J Ophthalmol 1987;103:38–43.
Escoffery RF, Olk RJ, Grand MG et al.: Vitrectomy without scleral buckling for primary rhegmatogenous retinal detachment. Am J Ophthalmol 1985;99:275–281.
Heimann H, Hellmich M, Bornfeld N et al.: Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment (SPR Study): Design issues and implications. SPR Study report no. 1. Graefes Arch Clin Exp Ophthalmol 2001;239:567–574.
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Heimann H, Kirchhof B: Primary vitrectomy in rhegmatogenous retinal detachment. In: Ryan SJ, Wilkinson CP (eds). Retina. St Louis: CV Mosby Co; 2005; pp. 2085–2094.
Heimann H, Ulrich Bartz-Scmidt K, Bornfeld N et al.: Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment. A prospective randomized multicenter clinical study. Ophthalmology 2007;114:2142–2154.
Leaver P. Expanding the role of vitrectomy in retinal reattachment surgery.
Br J Ophthalmol 1993;77:197.
Machemer R, Buettner H, Norton EW et al.: Vitrectomy: A pars plana approach. Trans Am Acad Ophthalmol Otolaryngol 1971;75:813–820.
Minihan M, Tanner V, Williamson TH: Primary rhegmatogenous retinal detachment: 20 years of change. Br J Ophthalmol 2001;85:546–548.
Schepens CL, Hartnett ME, Hirose T: Schepens’ Retinal Detachment and Allied Diseases. 2nd Edition. Boston: Butterworth-Heinemann, 2000; pp. 325–346.
Wilkinson CP: Wanted: Optimal data regarding surgery for retinal detachment. Retina 1998;18:199–201.
Wilkinson CP, Rice TA: Michels Retinal Detachment. St Louis: CV Mosby Co; 1997; pp. 773–906.
10
Selection of Surgery for “Routine” Retinal Detachment
Most rhegmatogenous retinal detachments are blinding disorders unless they are successfully repaired. They were regarded as incurable until the seminal work of Jules Gonin in the 1920s, when an anatomical success
rate approaching 50% was first described (see Chapter 1). Anatomical results for routine retinal detachments slowly improved through several decades, reaching the current 85%–90% single-operation success figure for scleral buckling by the 1980s. Unfortunately, a similar improvement in visual results has not occurred because of the profound influence of preoperative macular detachment.
Scleral buckling, once the sole standard of care for uncomplicated cases, has become much less popular worldwide with the development of alternative options starting in the mid 1980s. The most enduring of these are pneumatic retinopexy (PR) (described in Chapter 8) and vitrectomy (described in Chapter 9). Vitrectomy was originally reserved for complicated detachments but became popular for more routine cases as experience and equipment improved. Today, particularly in the United States, scleral buckling, PR, and vitrectomy are standards of care that are widely employed in the management of “routine” or “uncomplicated” retinal detachment, but how frequently each is used varies among different demographic groups. For instance, the popularity of PR varies by geographical location and scleral buckling appears less popular in the hands of relatively young vitreoretinal specialists.
It can be useful to discuss objective clinical criteria that may favor one technique over another. Demarcation, scleral buckling, PR, vitrectomy, and vitrectomy plus scleral buckling have relative indications and contraindications (Table 10–1), as well as limitations and complications. In this brief chapter, clinical factors that may influence the choice of one technique over another, for the types of cases
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