Abstract
Objective
To describe an optic capture pars plana lensectomy technique.
Methods
After core vitrectomy, pars plana lensectomy is performed with preservation of the anterior capsule. Capsulorhexis is performed on the preserved anterior capsule through a 2.8 mm clear corneal incision. An intraocular lens (IOL) is placed in the ciliary sulcus, and then the optic of the IOL is pushed back to the vitreous cavity so that the optic is captured by the surrounding capsulorhexis margin.
Results
The captured IOL-capsule diaphragm remained stable during air–fluid exchange and prevented air prolapse to the anterior chamber. IOL stability and a clear visual axis were preserved during the follow-up period.
Conclusion
With this modified pars plana lensectomy technique, stable IOL position and clear visual axis can be maintained when a pars plana approach is needed during combined cataract and vitreoretinal surgery.
Introduction
Phacoemulsification has become a standard method in modern combined cataract and vitreoretinal surgery due to advances in equipment and techniques. Pars plana lensectomy, however, could be a better approach in certain settings, such as existing posterior polar cataract,Citation1 pediatric patients,Citation2 or traumatic cataract in which the posterior capsule is already damaged.Citation3
Major disadvantages of pars plana lensectomy as compared to phacoemulsification include: compromised capsular bag due to the removal of the posterior capsule during lensectomy; subsequent less stable intraocular lens (IOL) position in the ciliary sulcus, with an increased risk of tilting or dislocation of the IOL; risk of air/silicone oil prolapse to the anterior chamber if a large anterior capsulotomy was made; and development of opacification of the remaining anterior capsule, if the anterior capsule was preserved.
The author introduces an optic capture pars plana lensectomy technique in which – after an anterior capsule preserving lensectomy – capsulorhexis is made on the remaining anterior capsule followed by optic capture of an IOL into the capsulorhexis to resolve the shortcomings of conventional pars plana lensectomy.
Patient and methods
The patient was a 60-year-old woman with diabetic vitreous hemorrhage and tractional retinal detachment combined with thick posterior polar cataract.
Surgical technique
Anterior capsule-preserving pars plana lensectomy
A standard preparation for 20-gauge pars plana vitrectomy was made, including conjunctival peritomy and three sclerotomies. After a core vitrectomy was performed, the nucleus of the lens was initially crushed with a microvitreoretinal blade and a 20-gauge needle introduced through a superotemporal and superonasal sclerotomies, respectively (). The nucleus was then removed with a fragmatome and a vitreous cutter through the pars plana, and cortical cleaning was performed using the active vacuum of the vitreous cutter (). The posterior capsule was removed during the procedure, but care was taken to preserve the anterior capsule.
Capsulorhexis on the remaining anterior capsule and capture of the optic of an intraocular lens to the capsulorhexis
After completion of the vitrectomy, viscoelastic material was introduced into the anterior chamber through a side-port stab incision, and a superior clear corneal incision of 2.8 mm in length was made. After complete replacement of the aqueous humor with viscoelastic material (), a small puncture was made on the preserved anterior capsule with a bent needle (). Then capsulorhexis was performed using capsulorhexis forceps ().
After a foldable IOL was inserted into the ciliary sulcus through the corneal incision, one side of the optic was pushed back into the vitreous cavity with a Sinskey hook and then the other side of the optic was pressed in the same manner, 90° from the haptic–optic junction ().
Results
Intraoperative findings
The successfully captured optic made an oval capsular configuration (). No difficulty was encountered in viewing the fundus through the captured optic. Even after fluid–air exchange, the capsule-IOL diaphragm was stable enough to prevent air in the vitreous cavity from migrating to the anterior chamber (). Additional procedures such as endolaser photocoagulation were able to be performed as usual.
Discussion
Traditional pars plana lensectomy involves removing both the anterior and posterior capsule along with the crystalline lens to prevent later development of anterior capsular opacity. An anterior chamber IOL or scleral sutured posterior chamber IOL is then used. An alternative approach was to save the anterior capsule during the lensectomy followed by placing an IOL in the ciliary sulcus. An anterior capsulotomy, either by vitreous cutter or diathermy, was then made at the center of the anterior capsule to prevent anterior capsular opacification in the visual axis.Citation1,Citation2 By creating a capsulotomy, however, another concern is raised regarding the breakage of the stable capsular barrier. This could be especially problematic during air–fluid exchange in combined cataract and vitreous surgery, since the IOL can be subluxated by the air pressure in the vitreous cavity and the air can prolapse to the anterior chamber,Citation4 increasing the risk of corneal endothelial cell loss.Citation5 Some surgeons prefer to insert an IOL in a secondary operation, when fluid–air exchange or silicone oil injection is needed.Citation4 The risk of neovascular glaucoma could also increase by free diffusion of vascular growth factors from the ischemic retina to the anterior chamber in ischemic retinal diseases, such as diabetic retinopathy.
Preservation of the anterior capsule after the lensectomy could have merits in this regard. Pars plana vitrectomy combined with pars plana lensectomy with anterior capsular preservation can facilitate sufficient removal of anterior and peripheral vitreous, allow sufficient application of endolaser photocoagulation, and prevent acute increase of vascular endothelial growth factor and inflammatory cytokine production postoperatively.Citation6
Another option is to polish the posterior surface of the anterior capsule in the visual axis to remove as many endothelial cells as possible, using either the vacuum of the vitreous cutter or polishing instruments.Citation4 Still, concerns exist regarding tilting or decentration of the IOL, due to the less stable location in the ciliary sulcus than in the capsular bag.
The modified technique described here can solve all these problems. The captured IOL in the capsulorhexis can work like an IOL in the capsular bag, keeping a tight seal of the lens-iris diaphragm intraoperatively and postoperatively, and reduces concerns about dislocation or subluxation of the IOL and capsular opacity in the visual axis.
The optic-capture technique was originally used in pediatric cataract surgeries on the posterior capsule to preserve a clear visual axis.Citation7 Numerous variations of this technique have been reported so far.Citation8–Citation12 Likewise, performing a capsulorhexis on the remaining anterior capsule after all the lens material has been removed could be done in the same fashion as during conventional phacoemulsification. The size of the capsulorhexis is ideal to achieve a secure capture if it is 1–2 mm smaller than the IOL optic.Citation13
In summary, in a situation when pars plana lensectomy is needed, anterior capsule-preserving pars plana lensectomy followed by capsulorhexis and optic capture on the preserved capsule could be a useful option. This technique offers maintenance of stable IOL position and a clear visual axis. Long-term follow-up in more patients will be needed to address possible complications related to this technique and long-term outcomes.
Disclosure
The author has no financial interest related to the article.
References
- GhoshYKKirkbyGRPosterior polar cataract surgery – a posterior segment approachEye (Lond)200822684484817332769
- MillerDMMurrayTGCicciarelliNLCapoHMarkoeAMPars plana lensectomy and intraocular lens implantation in pediatric radiation-induced cataracts in retinoblastomaOphthalmology200511291620162416024083
- YasukawaTKitaMHondaYTraumatic cataract with a ruptured posterior capsule from a nonpenetrating ocular injuryJ Cataract Refract Surg19982468688699642603
- MacCumberMWPackoKHCivantosJMGreenbergJBPreservation of anterior capsule during vitrectomy and lensectomy for retinal detachment with proliferative vitreoretinopathyOphthalmology2002109232933311825819
- MitamuraYYamamotoSYamazakiSCorneal endothelial cell loss in eyes undergoing lensectomy with and without anterior lens capsule removal combined with pars plana vitrectomy and gas tamponadeRetina2000201596210696749
- KinoshitaNOtaAToyodaFYamagamiHKakehashiASurgical results of pars plana vitrectomy combined with pars plana lensectomy with anterior capsule preservation, endophotocoagulation, and silicon oil tamponade for neovascular glaucomaClin Ophthalmol201151777178122267911
- GimbelHVDeBroffBMPosterior capsulorhexis with optic capture: maintaining a clear visual axis after pediatric cataract surgeryJ Cataract Refract Surg19942066586647837081
- MenapaceRPosterior capsulorhexis combined with optic buttonholing: an alternative to standard in-the-bag implantation of sharp-edged intraocular lenses? A critical analysis of 1000 consecutive casesGraefes Arch Clin Exp Ophthalmol2008246678780118425525
- JonesJJOettingTARogersGMJinGJReverse optic capture of the single-piece acrylic intraocular lens in eyes with posterior capsule ruptureOphthalmic Surg Lasers Imaging Epub September 6, 2012
- LeeJEAhnJHKimWSJeaSYOptic capture in the anterior capsulorhexis during combined cataract and vitreoretinal surgeryJ Cataract Refract Surg20103691449145220692553
- VasavadaARPraveenMRTassignonMJPosterior capsule management in congenital cataract surgeryJ Cataract Refract Surg201137117319321183112
- TassignonMJDe VeusterIGodtsDKosecDVan den DoorenKGobinLBag-in-the-lens intraocular lens implantation in the pediatric eyeJ Cataract Refract Surg200733461161717397732
- GimbelHVDeBroffBMIntraocular lens optic captureJ Cataract Refract Surg200430120020614967291