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Posterior chamber lens implantation combined with pars plana vitrectomy
Posterior chamber lens implantation combined with pars plana vitrectomy A.M. McElvanney, FRCOphth, E.M. Talbot, FRCOphth ABSTRACT Purpose: To assess the outcome of cataract extraction and posterior chamber intraocular lens (IOL) implantation combined with pars plana vitrectomy. Setting: Ophthalmic ward in a district general hospital. Methods: This study evaluated seven consecutive patients who had cataract extraction, IOL implantation, and pars plana vitrectomy in one procedure. Four patients were diabetic, and three had perforating eye injuries with cataract formation and intraocular foreign bodies. Results: No significant postoperative complications occurred, and the posterior chamber lenses were well tolerated. In all cases, good subjective visual improvement was achieved and visualization of the posterior pole was excellent. Conclusion: Combining cataract extraction with posterior chamber IOL implantation and vitrectomy in one procedure may be indicated, especially if there is traumatic rupture of the lens capsule. J Cataract Refract Surg 1997; 23:106-110
"\VJhen considering combined cataract surgery and W vitrectomy, there are three factors to contemplate. First, co-existing lens and vitreous pathology is considered to be the main indication for combined cataract extraction, posterior chamber intraocular lens (IOL) implantation, and vitrectomy. If lens opacities impede the view of the posterior pole, cataract removal is required to facilitate vitrectomy surgery. Extracapsular cataract extraction,I-3 phacoemulsification,4-7 and lensectomT,8 have all been described as part of the combined procedure. Second, lens opacities tend to develop or progress after pars plana vitrectomy.9,10 It may, therefore, be reasonable to remove the lens at vitrectomy if there is already moderate lens opacity, particularly if the capsule has been ruptured as a result of injury. From Royal Preston Hospital, Preston, United Kingdom. Reprint requests to E.M Talbot, FRCOphth, Comultant Ophthalmic Surgeon, Royal Preston Hospital, Sharoe Green Lane, Preston PR2 4HT, United Kingdom. 106
Finally, if cataract extraction with IOL implantation is performed at a later date after the vitrectomy, surgery is technically more difficult because of zonular weakness and absence of vitreous support for the lens. Furthermore, leaving the eye aphakic (without posterior capsule) impairs visual rehabilitation and increases the risk of neovascular glaucoma. 10-12
Materials and Methods Combined cataract extraction with posterior chamber IOL implantation and vitrectomy was performed in seven patients (six men, one woman) under general anesthesia over 10 months. Mean patient age was 53 years (range 25 to 70 years). Four patients were diabetic (three non-insulin dependent, one insulin dependent). The main indications for vitrectomy were persistent vitreous hemorrhage for 12 months in four patients (all diabetics) and perforating eye injury with cataract formation and suspected intraocular foreign body in three cases.
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
PC IOL IMPLANTATION WITH VITRECTOMY
The surgical aims were to improve the view of the posterior pole to allow a subjective improvement in visual acuity, to permit fundus assessment by removing vitreous hemorrhage and lens opacity, to allow laser treatment if required, and to enable foreign-body removal. Two patients with diabetes had extracapsular cataract extraction (ECCE), two with diabetes and one with a perforating eye injury had phacoemulsification, and two with perforating eye injury had Ocutome lens aspiration. Sodium hyaluronate (Healon®) was used in all cases. Vitrectomy was by a standard three-port pars plana procedure combined with indentation. Three patients with diabetes had laser endophotocoagulation for proliferative diabetic retinopathy. None had preoperative rubeosis. Surgical technique is shown in Figures 1 and 2. Skin and conjunctiva were prepared with aqueous povidoneiodine (Betadine®). Immediately before surgery, subconjunctival injections of mydricaine and cephradine were given. Next, the conjunctiva was opened and the port sites were prepared and cauterized. A nonpenetrating sclerolamellar flap was made. The infusion port was then inserted inferotemporally with the infusion turned off to facilitate infusion of the eye after scleral closure. The cataract was removed and a posterior chamber IOL inserted in the capsular bag in eyes with an intact posterior capsule. The scleral incision was then closed with a frequent-bite, 10-0 nylon, boo dace suture, and the two remaining ports were placed in the eye. A standard
o
o
ot
Inferotemporal infusion point
Figure 1. (McElvanney) Sclerolamellar section and position of ports.
Figure 2. (McElvanney) Stepped sclerolamellar section (cross section).
three-port pars plana vitrectomy with indentation was performed. In the three cases of perforating eye injury with intraocular foreign bodies, the foreign body was removed with forceps through a sclerotomy in two cases. In the third case, a suspected organic foreign body seen on ultrasound B-scan was found to be a dislocated lens fragment resting on the retina. The posterior chamber IOL was placed in the capsular bag in 5 cases and in front of a rim of anterior capsule in one traumatic case. In the final patient, the c. d'lU the CI'1'lary suIcus 13,14 because 0 f lU. Iens was nxate adequate capsular support. The supporting knots were buried under a scleral lamella. All IOLs were single piece; two were surface modified.
Results Table 1 summarizes the outcome of the combined procedure. All patients had a subjective improvement in visual acuity, and good visualization of the fundus was obtained. In two patients with diabetes (patients 1 and 2), visual acuity remained at counting fingers as a result of severe diabetic retinopathy and macular pathology. Visual acuity in one eye with perforating eye injury (patient 7) remained poor because of the extent of the injury and pre-existing intraocular inflammation. Only two patients (patients 5 and 6) required a further postoperative procedure. One had a neodymium:YAG (Nd: YAG) capsulotomy and suture removal at 4 months and the other, Nd:YAG division of a vitreous strand that was causing pupillary distortion. There were no significant postoperative complications; specifically, no patient developed rubeosis. There was no clinical difference in recovery between eyes with a surface-modified IOL and those with an unmodified lens.
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
107
PC 10L IMPLANTATION WITH VITRECTOMY
Table 1. Patient characteristics and outcomes.
Patient
2
3 4
5 6 7
Preop Condition Diabetes Diabetes Diabetes Diabetes Trauma' Trauma' Trauma'
Visual Acuity Preop
Postop
CF CF HM HM HM
CF
Follow-up (Months)
6 4
6/60+ 1 6/60 6/9 6/5
6/9 HM
CF
6 11
5 5 3
Comments Macular edema; thickened edematous retina; peripapillary gliosis Circinate maculopathy; gliosis Circinate maculopathy; gliosis Disciform macular degeneration; optic atrophy; venous occlusion Nd:YAG capsulotomy, suture removal Nd:YAG division of vitreous strand Severe penetrating eye injury with hypopyon
'Perforating eye injury with intraocular foreign body
Discussion When undertaking a combined procedure, the sur~ geon must decide whether to perform the cataract ex~ traction and posterior chamber 10L implantation before or after the vitrectomy. Both techniques have advantages and disadvantages. If cataract extraction and 10L implantation are performed before the vitrectomy, manipulation of the cornea and irrigation with basic salt solution may result in intraoperative corneal edema, which could hinder visualization of the retina. 4 ,7 The large corneoscleral wound required for ECCE may result in a wound leak or iris prolapse if intraocular pressure is raised during vitrec~ tomy. 4 In addition, intraoperative astigmatism might compromise the fundal view. These wound problems are minimized by using a stepped, sclerolamellar incision closed with a frequent~bite, continuous suture to produce a well~sealed wound. Other complications of combined surgery include intraoperative hyphema or miosis. 5 The use of preoperative mydricaine and 1: 1000 adrenaline infusion helps prevent miosis. Although obtaining a clear view of the retinal periphery at the optic edge may be difficult, this can be minimized if a 7.0 mm optic is used. Finally, 10L dislocation has been described. Some surgeons therefore recommend that cataract extraction and lens implanta~ tion be performed as a separate procedure 2 to 4 weeks before the vitrectomy to allow the hap tics to fix by fibrosis, reducing the risk of lens dislocation. 1 In our study, none of these problems was encountered. If cataract extraction is done after the vitrectomy, the hazy view caused by the cataract may make vitrec~ tomy hazardous. Subsequently, the absence of vitreous 108
support for the lens may cause difficulty in nuclear expression, necessitating use of additional surgical instrumentation. 15 ,16 Furthermore, capsule rupture would result in a loss of lens fragments posteriorly.17,l8 However, if aspiration is maintained, the lens fragments will return to the aspiration port. Phacoemulsification was done in three of our patients with diabetes. Theoretical advantages are that the smalllimbal incision reduces intraoperative corneal dis~ tortion and ensures a sutured, watertight wound during vitrectomy. However, phacoemulsification is not suitable for very dense, nuclear, sclerotic cataracts and is contraindicated in traumatic cataracts in the presence of a lens/vitreous mixture, evidence of zonular dehiscence, or a large posterior capsule tear. In these circumstances, phaco-probe aspiration ofvitreous would cause excessive vitreous traction and might result in a retinal tear? When an intraocular foreign body is suspected, preoperative ultrasonography is usually helpful in detecting a ruptured posterior capsule or associated retinal detachment; however, it can be misleading. For example, a localized vitreous blood clot (Figure 3, leftJ or gas bubble or lens matter (Figure 3, right) can be mistaken for an intraocular foreign body. When performing cataract surgery in diabetics, it is important to try to preserve the posterior capsule to reduce the risk of rubeosis.1 2 ,19,20 ' Several advantages of the combined procedure have been oudined. 1- s A better view of the posterior pole is obtained during vitrectomy if cataract surgery is performed immediately. Also, the posterior capsule does not have time to opacify. The improved fundal view allows laser photocoagulation to be performed im-
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
PC IOL IMPLANTATION WITH VITRECTOMY
/
/~~l !~
),
~\
I
I
\
(
\
~
Blood clot in vitreous
\ Lens matter
Figure 3. (McElvanney) Ultrasound artifacts mistaken as foreign bodies. Left: Linear blood clot in vitreous. Right: Gas bubble and lens matter.
mediately, reducing the risk of rubeosis and vitreous hemorrhage from proliferative retinopathy. Other considerations are patient convenience and reduced total operating time. Finally, insertion of a posterior chamber IOL allows better visual rehabilitation than leaving the patient aphakic. It should be remembered that diabetic keratopathy may lead to contact lens intolerance. 21 Our cases suggest that performing cataract extraction, IOL implantation, and vitrectomy in one operation is safe and allows speedy visual recovery with few complications and a good technical result. However, it remains the surgeon's preference whether to carry out a combined procedure or to perform surgery at two sittings.
References 1. Benson WE, Brown GC, Tasman W, McNamara ]A.
Extracapsular cataract extraction, posterior chamber lens insertion and pars plana vitrectomy in one operation. Ophthalmology 1990; 97:918-921 2. Menchini U, Azzolini C, CameSasca FI, Brancato R. Combined vitrectomy, cataract extraction, and posterior chamber intraocular lens implantation in diabetic patients. Ophthalmic Surg 1991; 22:69-73 3. Kokame GT, Flynn HW, Blankenship GW. Posterior chamber intraocular lens implantation during diabetic pars plana vitrectomy. Ophthalmology 1989; 96: 603610 4. Koenig SB, Mieler WF, Han DP, Abrams GW. Combined phacoemulsi6cation, pars plana vitrectomy, and posterior chamber intraocular lens insertion. Arch Ophthalmol 1992; 11 0: 11 0 1-11 04
5. Mamalis N, Teske MP, Kreisler KR, et al. Phacoemulsification combined with pars plana vitrectomy. Ophthalmic Surg 1991; 22:194-198 6. Mackool R]. Pars plana vitrectomy and posterior chamber intraocular lens implantation in diabetic patients (letter). Ophthalmology 1989; 96:1679-1680 7. Koenig SB, Han DP, Mieler WF, et al. Combined phacoemulsification and pars plana vitrectomy. Arch Ophthalmol 1990; 108:362-364 8. Slusher MM, Greven CM, Yu DD. Posterior chamber intraocular lens implantation combined with lensectomy-vitrectomy and intraretinal foreign-body removal. Arch OphthalmoI1992; 110:127-129 9. Blankenship GW, Machemer R. Long-term diabetic vitrectomy results; report of 10 year follow-up. Ophthalmology 1985; 92:503-506 10. SchachatAP, Oyakawa RT, Michels RG, Rice TA. Complications of vitreous surgery for diabetic retinopathy. II. Postoperative complications. Ophthalmology 1983; 90: 522-530 11 . Blankenship G, Cortez R, Machemer R. The lens and pars plana vitrectomy for diabetic retinopathy complications. Arch Ophthalmol1979; 97:1263-1267 12. Rice TA, Michels RG, Maguire MG, Rice EF. The effect of lensectomy on the incidence of iris neovascularization and neovascular glaucoma after vitrectomy for diabetic retinopathy. Am] Ophthalmol1983; 95:1-11 13. Lamkin ]C, Azar DT, Mead MD, Volpe NJ. Simultaneous corneal laceration repair, cataract removal, and posterior chamber intraocular lens implantation. Am ] OphthalmoI1992; 113:626-631 14. Berger RR, Meyers M. Ciliary sulcus fixation-still a shot in the dark (letter). ] Cataract Refract Surg 1991; 17: 864-865 15. Smiddy WE, Stark WJ, Michels RG, et al. Cataract extraction after vitrectomy. Ophthalmology 1987; 94: 483-487
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
109
PC IOL IMPLANTATION WITH VITRECTOMY
16;' Sneed S, Parrish RK II, Mandelbaum S, O'Grady G. Technical problems of extracapsular cataract extractions after vitrectomy (letter). Arch Ophthalmol 1986; 104: 1126-1127 17. Hutton WL, Pesicka GA, Fuller DG. Cataract extraction in the diabetic eye after vitrectomy. Am J Ophthalmol 1987; 104:1-4 18. Meyers SM, Klein R, Chandra S, Myers FL. Unplanned extracapsular cataract extraction in postvitrectomy eyes. Am J Ophthalmol 1978; 86:624-626
110
19. Blankenship GW. The lens influence on diabetic vitrectomy results; report of a prospective randomized study. Arch Ophthalmol1980; 98:2196-2198 20. Poliner LS, Christianson DJ, Escoffery RF, et al. Neovascular glaucoma after intracapsular and extracapsular cataract extraction in diabetic patients. Am J Ophthalmol 1985; 100:637-643 21. Schultz RO, Van Horn DL, Peters MA, et al. Diabetic keratopathy. Trans Am Ophthalmol Soc 1981; 79: 180199
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
"\VJhen considering combined cataract surgery and W vitrectomy, there are three factors to contemplate. First, co-existing lens and vitreous pathology is considered to be the main indication for combined cataract extraction, posterior chamber intraocular lens (IOL) implantation, and vitrectomy. If lens opacities impede the view of the posterior pole, cataract removal is required to facilitate vitrectomy surgery. Extracapsular cataract extraction,I-3 phacoemulsification,4-7 and lensectomT,8 have all been described as part of the combined procedure. Second, lens opacities tend to develop or progress after pars plana vitrectomy.9,10 It may, therefore, be reasonable to remove the lens at vitrectomy if there is already moderate lens opacity, particularly if the capsule has been ruptured as a result of injury. From Royal Preston Hospital, Preston, United Kingdom. Reprint requests to E.M Talbot, FRCOphth, Comultant Ophthalmic Surgeon, Royal Preston Hospital, Sharoe Green Lane, Preston PR2 4HT, United Kingdom. 106
Finally, if cataract extraction with IOL implantation is performed at a later date after the vitrectomy, surgery is technically more difficult because of zonular weakness and absence of vitreous support for the lens. Furthermore, leaving the eye aphakic (without posterior capsule) impairs visual rehabilitation and increases the risk of neovascular glaucoma. 10-12
Materials and Methods Combined cataract extraction with posterior chamber IOL implantation and vitrectomy was performed in seven patients (six men, one woman) under general anesthesia over 10 months. Mean patient age was 53 years (range 25 to 70 years). Four patients were diabetic (three non-insulin dependent, one insulin dependent). The main indications for vitrectomy were persistent vitreous hemorrhage for 12 months in four patients (all diabetics) and perforating eye injury with cataract formation and suspected intraocular foreign body in three cases.
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
PC IOL IMPLANTATION WITH VITRECTOMY
The surgical aims were to improve the view of the posterior pole to allow a subjective improvement in visual acuity, to permit fundus assessment by removing vitreous hemorrhage and lens opacity, to allow laser treatment if required, and to enable foreign-body removal. Two patients with diabetes had extracapsular cataract extraction (ECCE), two with diabetes and one with a perforating eye injury had phacoemulsification, and two with perforating eye injury had Ocutome lens aspiration. Sodium hyaluronate (Healon®) was used in all cases. Vitrectomy was by a standard three-port pars plana procedure combined with indentation. Three patients with diabetes had laser endophotocoagulation for proliferative diabetic retinopathy. None had preoperative rubeosis. Surgical technique is shown in Figures 1 and 2. Skin and conjunctiva were prepared with aqueous povidoneiodine (Betadine®). Immediately before surgery, subconjunctival injections of mydricaine and cephradine were given. Next, the conjunctiva was opened and the port sites were prepared and cauterized. A nonpenetrating sclerolamellar flap was made. The infusion port was then inserted inferotemporally with the infusion turned off to facilitate infusion of the eye after scleral closure. The cataract was removed and a posterior chamber IOL inserted in the capsular bag in eyes with an intact posterior capsule. The scleral incision was then closed with a frequent-bite, 10-0 nylon, boo dace suture, and the two remaining ports were placed in the eye. A standard
o
o
ot
Inferotemporal infusion point
Figure 1. (McElvanney) Sclerolamellar section and position of ports.
Figure 2. (McElvanney) Stepped sclerolamellar section (cross section).
three-port pars plana vitrectomy with indentation was performed. In the three cases of perforating eye injury with intraocular foreign bodies, the foreign body was removed with forceps through a sclerotomy in two cases. In the third case, a suspected organic foreign body seen on ultrasound B-scan was found to be a dislocated lens fragment resting on the retina. The posterior chamber IOL was placed in the capsular bag in 5 cases and in front of a rim of anterior capsule in one traumatic case. In the final patient, the c. d'lU the CI'1'lary suIcus 13,14 because 0 f lU. Iens was nxate adequate capsular support. The supporting knots were buried under a scleral lamella. All IOLs were single piece; two were surface modified.
Results Table 1 summarizes the outcome of the combined procedure. All patients had a subjective improvement in visual acuity, and good visualization of the fundus was obtained. In two patients with diabetes (patients 1 and 2), visual acuity remained at counting fingers as a result of severe diabetic retinopathy and macular pathology. Visual acuity in one eye with perforating eye injury (patient 7) remained poor because of the extent of the injury and pre-existing intraocular inflammation. Only two patients (patients 5 and 6) required a further postoperative procedure. One had a neodymium:YAG (Nd: YAG) capsulotomy and suture removal at 4 months and the other, Nd:YAG division of a vitreous strand that was causing pupillary distortion. There were no significant postoperative complications; specifically, no patient developed rubeosis. There was no clinical difference in recovery between eyes with a surface-modified IOL and those with an unmodified lens.
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
107
PC 10L IMPLANTATION WITH VITRECTOMY
Table 1. Patient characteristics and outcomes.
Patient
2
3 4
5 6 7
Preop Condition Diabetes Diabetes Diabetes Diabetes Trauma' Trauma' Trauma'
Visual Acuity Preop
Postop
CF CF HM HM HM
CF
Follow-up (Months)
6 4
6/60+ 1 6/60 6/9 6/5
6/9 HM
CF
6 11
5 5 3
Comments Macular edema; thickened edematous retina; peripapillary gliosis Circinate maculopathy; gliosis Circinate maculopathy; gliosis Disciform macular degeneration; optic atrophy; venous occlusion Nd:YAG capsulotomy, suture removal Nd:YAG division of vitreous strand Severe penetrating eye injury with hypopyon
'Perforating eye injury with intraocular foreign body
Discussion When undertaking a combined procedure, the sur~ geon must decide whether to perform the cataract ex~ traction and posterior chamber 10L implantation before or after the vitrectomy. Both techniques have advantages and disadvantages. If cataract extraction and 10L implantation are performed before the vitrectomy, manipulation of the cornea and irrigation with basic salt solution may result in intraoperative corneal edema, which could hinder visualization of the retina. 4 ,7 The large corneoscleral wound required for ECCE may result in a wound leak or iris prolapse if intraocular pressure is raised during vitrec~ tomy. 4 In addition, intraoperative astigmatism might compromise the fundal view. These wound problems are minimized by using a stepped, sclerolamellar incision closed with a frequent~bite, continuous suture to produce a well~sealed wound. Other complications of combined surgery include intraoperative hyphema or miosis. 5 The use of preoperative mydricaine and 1: 1000 adrenaline infusion helps prevent miosis. Although obtaining a clear view of the retinal periphery at the optic edge may be difficult, this can be minimized if a 7.0 mm optic is used. Finally, 10L dislocation has been described. Some surgeons therefore recommend that cataract extraction and lens implanta~ tion be performed as a separate procedure 2 to 4 weeks before the vitrectomy to allow the hap tics to fix by fibrosis, reducing the risk of lens dislocation. 1 In our study, none of these problems was encountered. If cataract extraction is done after the vitrectomy, the hazy view caused by the cataract may make vitrec~ tomy hazardous. Subsequently, the absence of vitreous 108
support for the lens may cause difficulty in nuclear expression, necessitating use of additional surgical instrumentation. 15 ,16 Furthermore, capsule rupture would result in a loss of lens fragments posteriorly.17,l8 However, if aspiration is maintained, the lens fragments will return to the aspiration port. Phacoemulsification was done in three of our patients with diabetes. Theoretical advantages are that the smalllimbal incision reduces intraoperative corneal dis~ tortion and ensures a sutured, watertight wound during vitrectomy. However, phacoemulsification is not suitable for very dense, nuclear, sclerotic cataracts and is contraindicated in traumatic cataracts in the presence of a lens/vitreous mixture, evidence of zonular dehiscence, or a large posterior capsule tear. In these circumstances, phaco-probe aspiration ofvitreous would cause excessive vitreous traction and might result in a retinal tear? When an intraocular foreign body is suspected, preoperative ultrasonography is usually helpful in detecting a ruptured posterior capsule or associated retinal detachment; however, it can be misleading. For example, a localized vitreous blood clot (Figure 3, leftJ or gas bubble or lens matter (Figure 3, right) can be mistaken for an intraocular foreign body. When performing cataract surgery in diabetics, it is important to try to preserve the posterior capsule to reduce the risk of rubeosis.1 2 ,19,20 ' Several advantages of the combined procedure have been oudined. 1- s A better view of the posterior pole is obtained during vitrectomy if cataract surgery is performed immediately. Also, the posterior capsule does not have time to opacify. The improved fundal view allows laser photocoagulation to be performed im-
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
PC IOL IMPLANTATION WITH VITRECTOMY
/
/~~l !~
),
~\
I
I
\
(
\
~
Blood clot in vitreous
\ Lens matter
Figure 3. (McElvanney) Ultrasound artifacts mistaken as foreign bodies. Left: Linear blood clot in vitreous. Right: Gas bubble and lens matter.
mediately, reducing the risk of rubeosis and vitreous hemorrhage from proliferative retinopathy. Other considerations are patient convenience and reduced total operating time. Finally, insertion of a posterior chamber IOL allows better visual rehabilitation than leaving the patient aphakic. It should be remembered that diabetic keratopathy may lead to contact lens intolerance. 21 Our cases suggest that performing cataract extraction, IOL implantation, and vitrectomy in one operation is safe and allows speedy visual recovery with few complications and a good technical result. However, it remains the surgeon's preference whether to carry out a combined procedure or to perform surgery at two sittings.
References 1. Benson WE, Brown GC, Tasman W, McNamara ]A.
Extracapsular cataract extraction, posterior chamber lens insertion and pars plana vitrectomy in one operation. Ophthalmology 1990; 97:918-921 2. Menchini U, Azzolini C, CameSasca FI, Brancato R. Combined vitrectomy, cataract extraction, and posterior chamber intraocular lens implantation in diabetic patients. Ophthalmic Surg 1991; 22:69-73 3. Kokame GT, Flynn HW, Blankenship GW. Posterior chamber intraocular lens implantation during diabetic pars plana vitrectomy. Ophthalmology 1989; 96: 603610 4. Koenig SB, Mieler WF, Han DP, Abrams GW. Combined phacoemulsi6cation, pars plana vitrectomy, and posterior chamber intraocular lens insertion. Arch Ophthalmol 1992; 11 0: 11 0 1-11 04
5. Mamalis N, Teske MP, Kreisler KR, et al. Phacoemulsification combined with pars plana vitrectomy. Ophthalmic Surg 1991; 22:194-198 6. Mackool R]. Pars plana vitrectomy and posterior chamber intraocular lens implantation in diabetic patients (letter). Ophthalmology 1989; 96:1679-1680 7. Koenig SB, Han DP, Mieler WF, et al. Combined phacoemulsification and pars plana vitrectomy. Arch Ophthalmol 1990; 108:362-364 8. Slusher MM, Greven CM, Yu DD. Posterior chamber intraocular lens implantation combined with lensectomy-vitrectomy and intraretinal foreign-body removal. Arch OphthalmoI1992; 110:127-129 9. Blankenship GW, Machemer R. Long-term diabetic vitrectomy results; report of 10 year follow-up. Ophthalmology 1985; 92:503-506 10. SchachatAP, Oyakawa RT, Michels RG, Rice TA. Complications of vitreous surgery for diabetic retinopathy. II. Postoperative complications. Ophthalmology 1983; 90: 522-530 11 . Blankenship G, Cortez R, Machemer R. The lens and pars plana vitrectomy for diabetic retinopathy complications. Arch Ophthalmol1979; 97:1263-1267 12. Rice TA, Michels RG, Maguire MG, Rice EF. The effect of lensectomy on the incidence of iris neovascularization and neovascular glaucoma after vitrectomy for diabetic retinopathy. Am] Ophthalmol1983; 95:1-11 13. Lamkin ]C, Azar DT, Mead MD, Volpe NJ. Simultaneous corneal laceration repair, cataract removal, and posterior chamber intraocular lens implantation. Am ] OphthalmoI1992; 113:626-631 14. Berger RR, Meyers M. Ciliary sulcus fixation-still a shot in the dark (letter). ] Cataract Refract Surg 1991; 17: 864-865 15. Smiddy WE, Stark WJ, Michels RG, et al. Cataract extraction after vitrectomy. Ophthalmology 1987; 94: 483-487
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997
109
PC IOL IMPLANTATION WITH VITRECTOMY
16;' Sneed S, Parrish RK II, Mandelbaum S, O'Grady G. Technical problems of extracapsular cataract extractions after vitrectomy (letter). Arch Ophthalmol 1986; 104: 1126-1127 17. Hutton WL, Pesicka GA, Fuller DG. Cataract extraction in the diabetic eye after vitrectomy. Am J Ophthalmol 1987; 104:1-4 18. Meyers SM, Klein R, Chandra S, Myers FL. Unplanned extracapsular cataract extraction in postvitrectomy eyes. Am J Ophthalmol 1978; 86:624-626
110
19. Blankenship GW. The lens influence on diabetic vitrectomy results; report of a prospective randomized study. Arch Ophthalmol1980; 98:2196-2198 20. Poliner LS, Christianson DJ, Escoffery RF, et al. Neovascular glaucoma after intracapsular and extracapsular cataract extraction in diabetic patients. Am J Ophthalmol 1985; 100:637-643 21. Schultz RO, Van Horn DL, Peters MA, et al. Diabetic keratopathy. Trans Am Ophthalmol Soc 1981; 79: 180199
J CATARACT REFRACT SURG-VOL 23, JANUARY/FEBRUARY 1997