retina surgery global perspectives Section Editors: Stanislao Rizzo, MD; Albert Augustin, MD; J. Fernando Arevalo, MD; and Masahito Ohji, MD Combined Phacoemulsification and Pars Plana Vitrectomy
Combining these procedures benefits both the surgeon and the patient.
By Francesco Barca, MD; and Stanislao Rizzo, MD
ataract formation is the most common comor- bidity in patients with vitreoretinal disease and Performing cataract extraction the most common complication of vitreoretinal surgery. The impact on visual acuity after vit- and intraocular lens implantation Crectomy is thus remarkable and requires, within a short at the time of vitrectomy, even time, removal of the cataract in order not to negate the if the cataract is not clinically result obtained with the vitrectomy. In the United States, significant, may be preferable the most common approach to these cases is to tackle the 2 diseases in 2 distinct phases: first, cataract surgery, to a second operation. and then pars plana vitrectomy, or vice versa. Outside the United States, however, vitreoretinal surgeons often erative and postoperative observations. Intraoperatively, perform these procedures in a single combined surgery it is necessary to consider what it means to perform cat- to maximize patient recovery and improve early visual aract surgery in vitrectomized eyes and, conversely, what rehabilitation. it means to perform vitrectomy in phakic eyes. The reported incidence of cataract after vitrectomy varies considerably among studies, ranging from 17% to Phacoemulsification in previously 82%,1,2 percentages that increase significantly in patients Vitrectomized Eyes older than 50 years.3 Several studies have been con- Performing cataract surgery in previously vitrecto- ducted to compare combined surgery with consecutive mized eyes poses additional risks compared with those surgery, most of which conclude that both procedures commonly encountered during phacoemulsification are safe and effective.3,4 However, in the case of consecu- in normal eyes. Intraoperative considerations include tive surgery, it is not uncommon for a patient who, after abnormal variations in the anterior chamber depth experiencing an initial improvement in visual acuity, later during phacoemulsification, unstable zonules, flaccid complains of impaired visual acuity, raising the question posterior capsule during cortical aspiration, and possible of whether that deterioration is due to cataract or retinal damage to the posterior capsule during previous vitrec- disease. tomy.6 In all of these cases, the risk of complications such as dropped nucleus or lost nuclear fragments is higher. REASONS FOR COMBINED SURGERY Therefore, gentle nucleus manipulation is necessary to To better understand why we prefer combined surgery avoid the risk of losing the nucleus posteriorly into the to consecutive surgery, we must consider some intraop- vitreous cavity during phacoemulsification. Indeed, cata-
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ract surgery in previously vitrectomized eyes has been reported to be more challenging than in eyes without previous vitrectomy.
Vitrectomy in Phakic Eyes Performing vitrectomy in phakic patients can be com- plicated by the impairment of the surgeon’s operative and postoperative views, restricted access to peripheral vitreoretinal pathology, and unintended damage to the crystalline lens. Furthermore, after vitrectomy, it may be difficult to determine whether a patient’s worsening of vision is caused by the underlying vitreoretinal pathology or by a cataract.
Postoperative Considerations To evaluate postoperative considerations, we selected 3 articles that discuss the visual recovery of phakic Figure 1. For combined phacoemulsification and vitrectomy, patients undergoing vitrectomy. Thompson7 evaluated the microcannulas are placed before phacoemulsification is the results of vitrectomy for epiretinal membrane in started. eyes with good preoperative visual acuities (20/50) and concluded that the procedure was safe and effective for cataract extraction as a sequential procedure (vitrec- these patients; however, he added that phakic patients tomy followed by cataract surgery); patients in group 3 require cataract surgery in order to achieve long-term underwent vitrectomy only (no cataract extraction); and improvement in visual acuity. Otherwise, the improve- patients in group 4 underwent vitrectomy and cataract ment obtained with vitrectomy is nullified by the onset extraction as a combined procedure. In this series, the of cataract. incidence of macular hole reopening was 11%, but the Muselier et al8 compared the visual outcomes of greatest risk of reopening was in group 2 (20% of cases), patients with idiopathic macular hole and cataract who the consecutive surgery group. underwent combined surgery versus consecutive surgery (cataract extraction performed within the first year after Combined Surgery: Phaco Plus Vitrectomy vitrectomy). In the combined surgery group, visual acuity Performing cataract extraction and intraocular lens improved significantly during the first 6 months and then implantation at the time of vitrectomy, even if the cata- proceeded slowly until the first postoperative year, with ract is not clinically significant, may be preferable to a no significant improvement between 6 and 12 months. second operation owing to the high rate of cataract In the consecutive group, however, the improvement in progression after vitrectomy surgery. There are several visual acuity was significant only after extraction of the advantages of combined surgery, including the reduced cataract. The reason for this difference in outcomes was surgical risk of a single operation, shorter postopera- cataract progression after vitreoretinal surgery in the con- tive visual rehabilitation, faster recovery, and increased secutive group, resulting in better and faster recovery of patient satisfaction. Further, better visualization of the patients who underwent combined surgery. posterior pole and the peripheral retina during vitrec- Another important consideration is the reopen- tomy can be achieved because lens removal allows a ing of previously closed macular holes that can occur complete vitrectomy with vitreous base shaving and thus after phacoemulsification. Macular hole reopening is a better gas and oil fill-in. well-known complication with an incidence between 0% and 16%. The reasons for this range in percentages SURGICAL TECHNIQUE vary but essentially depend on the length of follow-up, In considering which surgical technique to adopt, whether internal limiting membrane peeling is per- there is still an ongoing debate about 2 aspects: (1) Is it formed, and subsequent cataract extraction. Bhatnagar better to insert microcannulas before or after cataract et al9 conducted a retrospective study in which patients extraction?, and (2) is it better implant the IOL before with macular hole were divided into 4 groups. Patients or after vitrectomy? in group 1 were pseudophakic at presentation (prior Based on our initial experience using first-generation cataract extraction); patients in group 2 underwent trocars, because of the needle-like design of the trocar
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emulsification and the second for vitrectomy. Thus, after phacoemulsification, the surgeon was forced to wait for the operating room staff to relocate the 2 machines, remove the phaco, and approach the vitrector before proceeding to the posterior segment. Those movements were often obsolete and unnecessary and increased surgical time. The alternatives were combined machines that did not guarantee effective phacoemulsification. Today, having an instrument that effectively combines the 2 technologies makes the entire procedure more homogeneous and orderly. Figure 2. During combined surgery, the IOL should be implanted before vitrectomy. CONCLUSIONS Vitrectomy in phakic patients can be complicated by and the stepped-up diameter at the transitional area impairment of the surgeon’s operative and postopera- from the trocar to the cannula, relatively high force tive views, restricted access to peripheral vitreoretinal is required for insertion. Therefore, 3 microcannulas pathology, and unintended damage to the crystalline should be set up before making the corneal incision lens. Phacoemulsification following vitrectomy carries and performing cataract procedures, as this step could increased risks of posterior capsular tears, zonular dialy- increase IOP, leading to possible dehiscence of the sis, and loss of lens particles posteriorly. prior corneal wound and collapse of the anterior cham- Combined surgery has many advantages for both the ber (Figure 1). The current second-generation trocars are patient and the surgeon. The patient does not have to sharper and easier to introduce, but puncturing an eye return to the operating room for an additional surgical immediately after phacoemulsification with relatively low procedure, and the surgeon does not have to perform IOP may be difficult in any case, and, in addition, a previ- a potentially technically difficult second operation. ously positioned infusion line can permit a safer anterior Combining phacoemulsification with vitrectomy can vitrectomy if a rupture of the posterior capsule occurs. potentially hasten visual rehabilitation and prevent the In determining when to place the IOL, it is better to increased physical risks and medical costs associated insert the lens before vitrectomy (Figure 2) for 3 main with a second procedure in select patients. n reasons: First, the IOL opens and maintains the cap- sular bag opening. Second, if the implantation of the Francesco Barca, MD, is a vitreoretinal lens is postponed until the end of vitrectomy, it can be surgery fellow at the Academic Medical Centre, easy to damage the capsular bag during the maneuvers University of Amsterdam, Netherlands. of vitreous shaving, making it difficult if not impos- Stanislao Rizzo, MD, is Director of U.O. sible to insert the IOL. Third, in Chirurgia Oftalmica, Ospedale Cisanello,
our opinion, it is not true that the et Azienda Ospedaliero Universitaria Pisana in
presence of the IOL hinders the be .n Pisa, Italy. Dr. Rizzo is a member of the Retina tu
surgeon’s view of the fundus. e Today Editorial Board. He can be reached via For a video demonstration of a ey email at [email protected]. combined procedure, visit eyetube. eyetube.net/?v=kupen 1. de Bustros S, Thompson JT, Michels RG, et al. Nuclear sclerosis after vitrectomy for idiopathic epiretinal membranes. net/?v=kupen. Am J Ophthalmol. 1988;15:105(2):160-164. 2. Cherfan GM, Michels RG, de Bustros S, et al. Nuclear sclerotic cataract alter vitrectomy for idiopathic epiretinal membranes causing macular pucker. Am J Ophthalmol. 1991;15:111(4):434-438. SYSTEMS FOR COMBINED SURGERY 3. Thompson JT. The role of patient age and intraocular gas use in cataract progression after vitrectomy for macular A suitable machine for combined surgery must have a hole and epiretinal membranes. Am J Ophthalmol. 2004;137(2):250-257. 4. Rivas-Aguino P, Garcia-Amaris RA, Berrocal MH, Sanchez JG, Rivas A, Arevalo JF. Pars plana vitrectomy, good phacoemulsification system and the ability to have phacoemulsification and intraocular lens implantation for the management of cataract and proliferative diabetic 2 infusion lines, 1 for the anterior chamber and 1 for the retinopathy: comparison of a combined versus two-step surgical approach. Arch Soc Esp Oftalmol. 2009;84(1):31-38. 5. Sood V, Rahman R, Denniston K. Phacoemulsification and foldable intraocular lens implantation combined with posterior segment; it should be possible to activate these 23-gauge transconjunctival sutureless vitrectomy. J Cataract Refract Surg. 2009;35(8):1380-1384. infusion lines at the same time, simultaneously and inde- 6. Braunstein RE, Airiani S. Cataract surgery results after pars plana vitrectomy. Curr Opin Ophthalmol. 2003;14:150- 154. pendently providing infusion for the vitreous cavity and 7. Thompson JT. Epiretinal membrane removal in eyes with good visual acuities. Retina. 2005;25:875-882. irrigation for the anterior chamber. 8. Muselier A, Dugas B, Burelle X, et al. Macular hole surgery after cataract extraction: combined vs consecutive surgery. Am J Ophthalmol. 2010;150(3):387-391. Until a few years ago, combined surgery was per- 9. Bhatnagar P, Kaiser PK, Smith SD, Meisler DM, Lewis H, Sears JE. Reopening of previously closed macular holes after formed using 2 different machines, the first for phaco- cataract extraction. Am J Ophthalmol. 2007;144(2):252-259.
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