The protective properties of liquid perfluorocarbons in phacofragmentation of dislocated lenses

Trimanual vitrectomy for severe proliferative diabetic retinopathy

PURPOSE

To describe and evaluate a novel technique of pars plana vitrectomy (PPV) under chandelier illumination which is aided with the vital dyes and perfluorocarbon liquids for the management of the complex diabetic vitrectomy cases.

METHODS

We conducted a prospective interventional comparative study on 40 eyes of 36 patients with advanced diabetic eye disease requiring PPV. The study was conducted in a single tertiary referral center. Eyes were divided on 1:1 basis by stratified randomization into two groups. Group 1 had trimanual vitrectomy done assisted with chandelier illumination, perfluorocarbon liquid (PFCL) and vital dyes. Group 2 had the conventional bimanual vitrectomy done assisted with chandelier illumination only. All patients were followed up for a minimum of 6 months after the surgery.

RESULTS

Forty eyes of 36 patients with the mean age of 51.42 years (range 28-69) were evaluated. The anatomical success at 6 months could be achieved in all the eyes in both groups. The complete removal of the pre-retinal proliferations could be accomplished in all the eyes in the trimanual PPV group, and only in 85% of the eyes in the bimanual PPV group. Operative time was significantly shorter in the trimanual PPV group (p < 0.001). More eyes in the trimanual PPV group (55.0%) could achieve better vision (> 6/60) 6 months after the operation compared to the bimanual PPV group (50.0%), but this difference was not statistically significant.

CONCLUSION

Trimanual PPV is a novel, safe and effective technique that can improve the results of the complex diabetic PPV.

FIRST-IN-HUMAN CLINICAL STUDY TO INVESTIGATE THE EFFECTIVENESS AND SAFETY OF PARS PLANA VITRECTOMY SURGERY USING A NEW HYPERSONIC TECHNOLOGY

PURPOSE

Investigate the effective performance and safety of a new hypersonic vitrector technology.

METHODS

Postapproval, prospective, single-arm, noncomparative, open-label study at one clinical site in India.

INDICATIONS

macular hole (9/20), vitreous hemorrhage (7/20), vitreomacular traction (3/20), and vitreomacular traction with pseudomacular hole (1/20). Safety endpoints included intraoperative and postoperative adverse events. Effective performance endpoints were surgeon-rated effectiveness, range of surgical time, and device settings. Other performance measures were preoperative and postoperative best-corrected visual acuity, slit-lamp and indirect ophthalmoscopy, applanation tonometry, color fundus photography, fundus fluorescein angiography, and spectral domain optical coherence tomography.

RESULTS

Core vitreous removal (20/20 subjects), peripheral vitreous removal (18/20), and posterior vitreous detachment induction (13/15) surgeries were successfully completed. Total surgical time was 22.5 minutes to 106 minutes. Serious adverse events through 3 months were 2 device-associated retinal tears and detachment (one intraoperative) and one unrelated postoperative enlargement of macular hole with subretinal fluid.

CONCLUSION

This first-in-human study suggests that this new hypersonic vitrector technology is a promising alternative to commercially available guillotine vitrectors. The hypersonic vitrector was effective in core vitreous removal in all cases. Larger-scale studies are required to expand on our initial findings for induction of a posterior vitreous detachment or peripheral vitrectomy.

PERFLUOROCARBON LIQUIDS' ABILITY TO PROTECT THE MACULA FROM INTRAOCULAR DROPPING OF METALLIC FOREIGN BODIES: A Model Eye Study

PURPOSE

To examine the utility of perfluoro-n-octane (PFO) in balanced salt solution (BSS) to shield the macula from the impact of dropped metallic intraocular foreign bodies (IOFBs) by modeling scenarios in which they may fall during surgical removal.

METHODS

Model eyes were filled with various fluid mixtures (Group 1: 10% PFO/90% BSS; Group 2: 100% BSS; Group 3: 100% PFO; Group 4: 10% PFO/90% air; Group 5: 10% BSS/90% air). In Groups 1, 4, and 5, the 10% fluid volume covered the theoretical macula. For each fluid mixture, up to 30 IOFB drop scenarios were performed for each of the 5 sample IOFBs from 3 locations. Trajectories were recorded using a camera attached to a Zeiss operating microscope (Carl Zeiss, Jena, Germany). The percentages of IOFBs impacting the macula were calculated and Fisher exact test was used to assess differences.

RESULTS

In Group 1, 93% (417/450) of the dropped IOFBs were deflected by the PFO-BSS interface compared with 0% (0/500) in Groups 2, 3, 4, and 5 (P < 0.01). With the exception of the heaviest IOFB (24.4 mg), which impacted the macula in 30% of tests when dropped from the superior posterior segment (P < 0.01), all other IOFBs (2.8-13.4 mg) were deflected by the PFO-BSS interface in 100% of Group 1 drops (P < 0.01).

CONCLUSION

As demonstrated by these simulations, the PFO-BSS interface can deflect IOFBs dropped during surgery in a wide range of scenarios, especially when the IOFB is of lower mass.

Multiple methods of surgical treatment combined with primary IOL implantation on traumatic lens subluxation/dislocation in patients with secondary glaucoma

AIM

To describe clinical findings and complications from cases of traumatic lens subluxation/dislocation in patients with secondary glaucoma, and discuss the multiple treating methods of operation combined with primary intraocular lens (IOL) implantation.

METHODS

Non-comparative retrospective observational case series.

PARTICIPANTS

30 cases (30 eyes) of lens subluxation/dislocation in patients with secondary glaucoma were investigated which accepted the surgical treatment by author in the Ophthalmology of Xi'an No.4 Hospital from 2007 to 2011. According to the different situations of lens subluxation/dislocation, various surgical procedures were performed such as crystalline lens phacoemulsification, crystalline lens phacoemulsification combined anterior vitrectomy, intracapsular cataract extraction combined anterior vitrectomy, lensectomy combined anterior vitrectomy though peripheral transparent cornea incision, pars plana lensectomy combined pars plana vitrectomy, and intravitreal cavity crystalline lens phacofragmentation combined pars plana vitrectomy. And whether to implement trabeculectomy depended on the different situations of secondary glaucoma. The posterior chamber intraocular lenses (PC-IOLs) were implanted in the capsular-bag or trassclerally sutured in the sulus decided by whether the capsular were present.

MAIN OUTCOME MEASURES

visual acuity, intraocular pressure, the situation of intraocular lens and complications after the operations.

RESULTS

The follow-up time was 11-36mo (21.4±7.13). Postoperative visual acuity of all eyes were improved; 28 cases maintained IOP below 21 mm Hg; 2 cases had slightly IOL subluxation, 4 cases had slightly tilted lens optical area; 1 case had postoperative choroidal detachment; 4 cases had postoperative corneal edema more than 1wk, but eventually recovered transparent; 2 cases had mild postoperative vitreous hemorrhage, and absorbed 4wk later. There was no postoperative retinal detachment, IOL dislocation, and endophthalmitis.

CONCLUSION

To take early treatment of traumatic lens subluxation/dislocation in patients with secondary glaucoma by individual surgical plan based on the different eye conditions would be safe and effective, which can effectively control the intraocular pressure and restore some vision.

Perfluorocarbon liquid: its application in vitreoretinal surgery and related ocular inflammation

The application of perfluorocarbon liquids has been well acclaimed in vitreoretinal surgery. Its unique physical properties make it an ideal intraoperative tool to improve the efficiency and safety of surgical procedures in complicated cases. The main functions of perfluorocarbon liquids in vitreoretinal surgery include relocating and fixing the detached retina, displacing the subretinal and subchoroidal to fluid anteriorly, revealing proliferative vitreous retinopathy (PVR) for further maneuvers, protecting the macula from exposure to chemicals with potential toxicity, and assisting the removal of foreign body. The related clinical applications include retinal detachment with severe proliferative vitreoretinopathy, giant tear, diabetic retinopathy (DR), retinopathy of prematurity (ROP), and posterior dislocated crystalline and intraocular lenses. The application of perfluorocarbon liquids has been expended over the past fewer years. Several PFCLs related ocular inflammations have been observed in in vitro studies, animal studies, and clinical follow-up. The complete removal of PFCLs is recommended at the end of the surgery in most cases.

Clinical outcomes of sleeveless phacotip assisted levitation of dropped nucleus

BACKGROUND/AIM

To demonstrate the feasibility of a sleeveless phacotip-assisted approach to levitate dropped nucleus.

METHODS

This single-centre, retrospective, interventional, non-comparative case series reviewed the medical records of 34 eyes of 34 patients. Corrected and uncorrected distance visual acuity (CDVA, UDVA), early and late postoperative complications and ultrasound biomicroscopic (UBM) evaluation of the sclerotomy site was analysed.

RESULTS

At 18 months follow-up, the mean postoperative UDVA and CDVA in Snellen's decimal equivalent was 0.42 ± 0.16 and 0.91 ± 0.2, respectively. There was a significant improvement in the UDVA (p=0.001) and CDVA (p=0.002). Nucleus drop occurred following intraoperative posterior capsular rupture in 25 eyes (73.5%), zonular weakness in 5 eyes (14.8%) and post-trauma in 4 eyes (11.7%). In the early postoperative period, corneal oedema was seen in 2 eyes, pigment dispersion in 3 eyes and vitritis in 2 eyes. There was loss of CDVA in 1 (2.9%) eye due to persistent cystoid macular oedema. UBM did not reveal any vitreous incarceration into the sclerotomy site.

CONCLUSION

Dropped nucleus was successfully levitated into anterior chamber with this technique, resulting in a significant visual outcome with a favourable complication rate.

Management of posteriorly dislocated crystalline lens with perfluorocarbon liquid and fibrin glue-assisted scleral-fixated intraocular lens implantation

We describe a technique that uses a 23-gauge transconjunctival sutureless vitrectomy with perfluorocarbon liquid (PFCL) and phacoemulsification to manage a dropped nucleus. The PFCL is injected into the vitreous space until the dislocated lens reaches the iris plane and is then removed using phacoemulsification in the anterior chamber. After intraocular lens (IOL) implantation, a 23-gauge forceps is passed through the sclerotomy to grasp the IOL haptic, which is pulled onto the ocular surface. Tunnels are made at the edge of the flap with a 26-gauge needle into which the 2 haptics are tucked for additional stability. The scleral flaps and conjunctiva are then glued using biological glue. Perfluorocarbon liquid reduces lens repulsion and blocks the transmission of the ultrasound stream to the retina. The fibrin glue-assisted sutureless IOL implantation technique could reduce complications and suture-related problems.

Clinical outcomes of intraocular lens scaffold surgery: a one-year study

PURPOSE

To evaluate the safety and 1-year outcome of the intraocular lens (IOL) scaffold technique in eyes with soft to moderate nuclear remnants after intraoperative posterior capsule rupture (PCR).

DESIGN

Single-center, retrospective, interventional, noncomparative, consecutive case series.

PARTICIPANTS

A total of 20 eyes of 20 patients who had intraoperative PCR underwent IOL scaffold surgery in a tertiary clinic.

METHODS

A retrospective analysis of medical records of a consecutive series of patients who underwent IOL scaffold surgery from August 2011 to February 2013 was reviewed. All surgeries were performed by a single surgeon, and a 3-piece, 6.0-mm optic, acrylic, foldable IOL with a modified C-loop haptic configuration was implanted in all eyes.

MAIN OUTCOME MEASURES

The preoperative and postoperative parameters evaluated were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), specular microscopy, gonioscopy, ultrasound biomicroscopy, central macular thickness, intraocular pressure (IOP), and anterior and posterior segment inflammation. The final visual outcome at 1 year was evaluated.

RESULTS

At 1-year follow-up, the mean postoperative UDVA and CDVA in Snellen's decimal equivalent was 0.58 ± 0.15 and 0.90 ± 0.17, respectively. The IOL was placed in the sulcus for 14 eyes and in the capsular bag for 3 eyes, and glued intrascleral fixation of IOL was performed in 3 eyes. The mean postoperative refractive error at the final examination was -0.4 ± 0.05 diopter (standard error of mean). Postoperative CDVA of 20/20 and 20/30 was achieved in 75% (15 eyes) and 25% (5 eyes), respectively. There was no correlation between preoperative specular count and percentage loss of cells (P = 0.602; r(2)=0.015). The mean central macular thickness at 1 year was 182.5 ± 11.79 μm. Clinical macular edema was observed in 1 of 20 eyes (5%).

CONCLUSIONS

The IOL scaffold provided an effective, relatively noninvasive means of emulsifying moderate to soft nuclear remnants in eyes with intraoperative PCR, with a good visual outcome and a favorable complication rate.

Experimental measure of retinal impact force resulting from intraocular foreign body dropped onto retina through media of differing viscosity

BACKGROUND

To evaluate and compare the perfluorocarbon liquid, silicone oil, and viscoelastic against standard saline, in their ability to dampen the impact force of a foreign body, dropped within the eye. In an experimental surgical model in where cohesive and adhesive forces of the substances are not enough to float heavy-than-water foreign bodies.

METHODS

A model of ophthalmic surgery was constructed. A BB pellet was dropped from 24 mm onto a force transducer through four different fluids: balanced salt solution, perfluoro-n-octane, viscoelastic, and silicone oil. The impact energy (force) for each case was measured and recorded by the force transducer. The mean force of impact for each fluid was compared using the Student t-test.

RESULTS

Silicone oil resulted in the lowest force of impact. Both silicone oil and viscoelastic dampened the impact an order of magnitude more than perfluoro-n-octane and balanced salt solution.

CONCLUSIONS

Silicone oil and viscoelastic cushioned the force from a dropped BB. They may be useful adjuncts to prevent iatrogenic retinal injury during vitrectomy for intraocular foreign body removal.

Phacoemulsification with perfluorocarbon liquid using a 23-gauge transconjunctival sutureless vitrectomy for the management of dislocated crystalline lenses

BACKGROUND

We describe the modified technique of phacoemulsification in dislocated crystalline lenses.

METHODS

After the vitreous and posterior hyaloid membrane were removed using a 23-gauge three-port vitrectomy, perfluorocarbon liquid (PFCL) was injected at the posterior pole in order to fill the vitreous cavity. The dislocated lens floated on the PFCL, and the injection was ceased once the lens had risen to the iris plane. The lens was then removed from the anterior chamber using standard phacoemulsification procedures. During the phacoemulsification, the PFCL provides a support underneath the nucleus, like a trampoline, and even small fragments can be completely removed.

RESULTS

The final best-corrected visual outcome was more than 20/40 in 11 eyes. Although two eyes showed LP(-) due to optic neuropathy, those eyes showed a remission in inflammation and an increase in IOP.

CONCLUSION

This modified use of PFCL in the removal of dislocated lenses fragments may overcome the limitation of earlier management of dislocated lenses.

[Perfluorocarbon liquids and vitreoretinal surgery in 2011]

Perfluorocarbon liquids (PFCLs) are one of the most innovative recent tools for vitreoretinal surgery. PFCLs are characterized by their number of carbon atoms, which has an impact on the density, viscosity, surface tension, vapor pressure, the boiling point, and the refraction index. PFCLs are routinely used because of their high gravity (double that of water) and their low viscosity. Furthermore, they are immiscible in water, optically clear with refraction indices similar to that of water, allowing visualization of an interface between the PFCL and saline. The use of intravitreally injected liquid PFCLs as adjunctive agents to vitreoretinal surgery plays an important role in facilitating retinal reattachment, especially in cases of giant retinal tear, trauma, and/or proliferative vitreoretinopathy. PFCLs are also used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina (in proliferative diabetic retinopathy, for example), and manage the dislocated crystalline lens and intraocular lens.

Intravitreal bimanual surgery for residual lens fragments and displaced crystalline lenses

The authors have developed a new technique for removing large and hard lens fragments or crystalline lenses with hard nuclei dislocated into the vitreous cavity using an optic fiber-free intravitreal surgical system (OFFISS). The OFFISS visualizes the fundus without a fiberoptic and facilitates the bimanual technique. The lens materials are stabilized with one hand and the fragmatome to emulsify the lens fragments is controlled with the other. The lens fragments or subluxated crystalline lenses can be removed through 20-gauge incisions. This technique was used in 14 cases and was found to be safe and not invasive.

Clinical predictors and outcomes of pars plana vitrectomy for retained lens material after cataract extraction

PURPOSE

To determine current clinical predictors and visual outcomes of patients who undergo pars plana vitrectomy (PPV) for retained lens material.

DESIGN

Retrospective, noncomparative, consecutive case series.

METHODS

Medical records of 166 patients with complicated cataract surgery who underwent PPV for retained lens material at Retina Vitreous Consultants of Pittsburgh between January 1, 2001 and January 1, 2007 were reviewed. Main outcome measures include final visual acuity, development of glaucoma, retinal detachments, and cystoid macular edema.

RESULTS

At the final examination, 120 patients (72.3%) had a visual outcome of 20/40 or better and 18 patients (10.8%) had a visual outcome of 20/200 or worse. In patients without any preoperative eye conditions, 82.6% achieved a final vision of 20/40 or better. Multivariable analysis showed that predictors for visual outcomes of 20/40 or better were better presenting vision (P = .001), insertion of a posterior chamber lens (P = .005), and absence of preoperative eye disease (P = .001). Predictors for visual outcomes of 20/200 or worse were the absence of an anterior vitrectomy at cataract surgery (P = .005), absence of a sulcus lens (P = .011), presence of preexisting eye disease (P = .02), and development of glaucoma (P = .001). Performing a PPV within 7 days of cataract surgery was associated with a lower risk of developing glaucoma (P = .005).

CONCLUSIONS

Current techniques for management of retained lens material may contribute to improved visual outcomes based on our series. We recommend that the cataract surgeon perform an anterior vitrectomy, place a posterior chamber lens if possible, and consult a retina specialist for a PPV within 7 days to decrease the risk of developing secondary glaucoma.

Visual outcome of pars plana vitrectomy for retained lens fragments after phacoemulsification

Purpose:

To evaluate the visual outcome of patients who underwent pars plana vitrectomy (PPV) for posteriorly dislocated lens fragments after phacoemulsification.

Methods:

A retrospective chart review was conducted of all patients who had PPV for posteriorly dislocated lens fragments after phacoemulsification between January 2000 and September 2004 in the Vitreoretinal Service at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia. Demographics, preexisting eye diseases, details of the previous cataract surgery, findings at presentation, details of the vitreoretinal procedures, final visual acuity, and complications observed during the follow-up were evaluated.

Results:

Of the 60 patients identified, 37 patients (37 eyes) had a full set of data and were included in the study. In 21 eyes (56.8%), PPV was performed within 1 week of cataract extraction; in 15 eyes (40.5%), PPV was performed more than 1 week postcataract extraction. An initial visual acuity of 20/200 or worse was found in 34 eyes (91.9%). The final visual acuity was 20/40 or better in 10 eyes (27%), and 20/200 or worse in 13 eyes (35.1%). Retinal detachments were found in 3 eyes (8.1%): 1 before and 2 after vitrectomy.

Conclusion:

There was no statistically significant difference in outcome between those having vitrectomy the first week after cataract surgery and those having it later; however, there was a trend of better visual outcome in early vitrectomy patients (within 1 week).

Phacofragmentation with perfluorocarbon liquid and anterior chamber or scleral-fixated intraocular lens implantation for the management of luxated crystalline lenses

PURPOSE

To present a complex surgical technique used for the management of luxated crystalline lenses and evaluate treatment results.

SETTING

Department of Ophthalmology, Medical University of Lodz, Lodz, Poland.

METHODS

This prospective study involved 29 consecutive patients (30 eyes) with the mean age of 60.3 years. The applied surgical technique comprised pars plana vitrectomy, perfluorocarbon liquid injection, and crystalline lens phacofragmentation in the vitreous cavity. Simultaneously, anterior chamber intraocular lenses (IOLs) were implanted in 10 eyes, and scleral-fixated posterior chamber IOLs in 20 eyes. The follow-up mean was 5.2 month (range 1 to 16 months).

RESULTS

No complications were observed during phacofragmentation. Visual acuity improved in 22 cases and did not change in the other 8 eyes. The mean visual acuity was 0.40 +/- 0.37 (SD) (range between hand movements and 1.0) preoperatively and 0.68 +/- 0.34 (range 0.05 to 1.0) postoperatively. In 22 cases (73%), very good or good visual acuity (6/6 to 6/12) was achieved. There were no intraoperative complications. Postoperatively, transient hypotony was observed in 10 eyes, fibrinous reaction in the anterior chamber in 1 eye, dispersed blood in the vitreous cavity in 8 eyes, hyphema in 1 eye, corneal edema in 1 eye, vitritis in 3 cases, iris tug in 1 eye with an anterior chamber IOL, and slight dislocation of the scleral-fixated IOL in 1 case. Intraocular pressure was elevated in 11 eyes preoperatively; postoperatively, it normalized in 7 eyes without medication.

CONCLUSION

Phacofragmentation with perfluorocarbon liquid and IOL implantation for the management of luxated crystalline lenses was safe and effective method, providing good functional results.

Illuminated endochopper in the management of posteriorly dislocated lens nucleus

We describe the use of an illuminated endochopper (a prototype instrument produced by DORC International) in the management of a posteriorly dislocated lens nucleus or lens particles. This instrument helps to divide the lens nucleus or its fragments into small pieces and thus reduces time and ultrasound energy.

Retinal protection using a viscoadaptive viscoelastic agent during removal of a luxated crystalline lens by intravitreal phacoemulsification

PURPOSE

To report a method of retinal protection using a viscoadaptive viscoelastic agent during removal of a luxated crystalline lens by intravitreal phacoemulsification.

DESIGN

Interventional case report.

METHODS

A 65-year-old man presented with a totally luxated crystalline lens in the vitreous cavity of the left eye. After total vitrectomy was performed, a viscoadaptive viscoelastic agent was applied over the retina and optic disk. Then the luxated lens was removed by intravitreal phacoemulsification. The lens dropped several times during the surgery but the thick viscoadaptive viscoelastic agent protected the posterior retina.

RESULTS

In two cases treated this way, no complications occurred at six months after surgery.

CONCLUSION

This method may be useful for protecting the retina from damage by a luxated crystalline lens and is less costly than perfluorocarbon liquid.

Pars plana vitrectomy in the management of retained intravitreal lens fragments after cataract surgery

PURPOSE

To assess the outcome of patients who underwent pars plana vitrectomy for retained lens fragments after cataract surgery.

METHODS

A retrospective study of all consecutive cases with pars plana vitrectomy performed for retained lens fragment was conducted. Twenty-seven eyes of 27 patients were included in the study.

RESULTS

Twenty-four (89.9%) eyes received phacoemulsification. Pars plana vitrectomy was performed at the same sitting, or ranged from day 1-70 after cataract surgery. The mean follow up was 31.1 months. Final visual acuity of 6/12 or better was achieved in 15 (55.6%) patients. After excluding patients with pre-existing eye diseases, 68.4% of patients had visual acuity 6/12 or better. Complications after pars plana vitrectomy included glaucoma (22.2%), retinal detachment (11.1%) and surgically induced necrotizing scleritis (3.7%).

CONCLUSION

Ocular complications with poor visual outcome can occur after removal of intravitreal retained lens fragments complicating cataract surgery.

Management of dislocated lens material

Posterior dislocation of lens fragments is a well-known complication of phacoemulsification. Retained lens material in the vitreous cavity can lead to poor visual acuity related to inflammation, corneal edema, and glaucoma. Pars plana vitrectomy is frequently necessary to remove the dislocated lens fragments. The optimal timing of vitrectomy has not been firmly established. Several large studies have failed to establish an association between timing of vitrectomy and visual outcome. However, others suggest that earlier vitrectomy may lead to improved visual outcomes and lower rates of chronic glaucoma. Excellent outcomes are possible for patients undergoing vitrectomy for retained lens fragments. Retinal detachment is the most common cause of poor visual acuity in these patients. The risk of retinal detachment is correlated with vitreous manipulation by the cataract surgeon in attempts to retrieve dislocated lens material. Therefore, if both the anterior segment and vitreoretinal surgeons rigorously avoid vitreous traction in these cases, a good visual prognosis is expected.

Phacofragmentation without perfluorocarbon liquid for dislocated crystalline lenses or lens fragments after phacoemulsification

PURPOSE

To evaluate the clinical outcome of vitrectomy with phacofragmentation without perfluorocarbon liquid (PFCL) in the management of dislocation of the crystalline lens, caused by trauma, hereditary disorders, or hypermature cataracts, and lens fragments due to phacoemulsification.

METHODS

A prospective study was conducted to evaluate 30 eyes of 29 patients who had undergone standard pars plana vitrectomy with phacofragmentation without PFCL in the vitreous cavity, for the removal of dislocated crystalline lenses or lens fragments, from January 1998 to July 2000. All cases were followed for more than six months.

RESULTS

Final best corrected visual acuity of 0.5 or better increased from 0% preoperatively to 36.7% postoperatively, and 0.2 or better rose to 76.7%. The mean IOP was significant reduced, from 26.35 mmHg to 12.75 mmHg. No intraoperative complications occurred. Although two eyes (6.7%) developed retinal detachment, one (3.3%) had cystoid macular edema (CME) and one (3.3%) had a transient intraocular pressure increase (to 25 mmHg) postoperatively, all others had a favorable outcome.

CONCLUSIONS

Standard pars plana vitrectomy with phacofragmentation without PFCL in the vitreous cavity is a safe, simple, and effective method for removing a dislocated crystalline lens or lens fragments, with good visual outcome.

Determinants of visual outcome after pars plana vitrectomy for posteriorly dislocated lens fragments in phacoemulsification

PURPOSE

To evaluate the visual outcome of patients with posteriorly dislocated lens fragments after phacoemulsification managed with pars plana vitrectomy (PPV) and identify risk factors for poor visual outcome.

SETTING

Vitreo-Retinal Service, St. Paul Eye Unit, Liverpool, United Kingdom.

METHODS

The medical records of all patients who had PPV for posteriorly dislocated lens fragments after phacoemulsification between March 1993 and August 1998 were retrospectively reviewed. Demographics, preexisting eye conditions, details of the previous cataract surgery, findings at presentation, details of the vitreoretinal procedure, final visual acuity, and complications observed during the follow-up were evaluated. Univariate and multiple regression analyses were used to determine the significance of these clinical variables as determinants of poor visual outcome (visual acuity 6/12 or worse).

RESULTS

Of the 106 patients identified, 89 had a full set of data and were included in the study. In 79 patients (89%), PPV was performed from 1 to 357 days (median 15 days) after cataract extraction. In 10 patients (11%), PPV was done on the same day as the cataract surgery. Sixty-two patients (69%) had a final visual acuity of 6/12 or better. Preexisting eye disease (P <.01), PPV delayed for more than 4 weeks (P <.03), occurrence of retinal detachment after vitrectomy (P <.01), and the use of ultrasound (US) fragmentation (P <.01) were statistically significantly correlated with a poor visual outcome.

CONCLUSIONS

Posterior dislocated lens fragments after phacoemulsification were safely retrieved using PPV. It appears that intervening early (within 4 weeks) and avoiding the use of US fragmentation are associated with a better visual outcome and reduced rate of postoperative complications.

Management of posterior capsule tears

Any breach in the continuity of the posterior capsule is defined as a posterior capsule tear. Posterior capsule tears can be preexisting (congenital or traumatic), spontaneous, or intrasurgical. Preexisting/congenital posterior capsule tears have been related to an intrauterine insult. Posterior capsule tears due to trauma may occur as a consequence of direct mechanical impact due to perforation or blunt injury. Depending on the duration of time between the posterior capsular trauma and the cataract surgery, these posterior capsule tears can have different features. Intrasurgical posterior capsule tears are the most common and can occur during any stage of cataract surgery. Also, they may be planned in the form of primary posterior capsulorhexis. The conventional management consists of prevention of mixture of cortical matter with vitreous, dry aspiration, and anterior vitrectomy, if required. In addition, during phacoemulsification low flow rate, high vacuum, and low ultrasound are advocated if a posterior capsule tear occurs. Dislocated nucleus or nuclear fragments require vitrectomy and the use of perfluorocarbon liquids. In the presence of a posterior capsule tear, the IOL can be placed in the sulcus, if the capsular rim is available, or in the bag, if the tear is small. Scleral fixated posterior chamber lenses and anterior chamber IOLs can be implanted when the posterior capsule tear is large.

Management of retained intravitreal lens fragments after cataract surgery

With the rise of popularity of phacoemulsification as the preferred surgical method for cataract extraction, there has been an increased incidence of posterior dislocation of lens fragments. The appropriate management of this complication both during and after cataract extraction is discussed in this review. It is suggested that vigorous attempts by the cataract surgeon to retrieve intravitreal lens fragments should be avoided. Timely referral to a posterior segment surgeon for pars plana vitrectomy and removal of lens fragments can result in good visual outcome. Complications, such as glaucoma and retinal detachment, may develop in some cases. The importance of careful clinical follow-up is emphasized.

The management of dislocated lens material after phacoemulsification

PURPOSE

To determine the visual outcome, prognostic factors, and effect of timing of surgical intervention in patients with retained lens fragments after phacoemulsification.

METHODS

A retrospective review was carried out of the notes of 44 consecutive patients who suffered posterior dislocation of lens fragments during phacoemulsification, of whom 34 underwent vitrectomy.

RESULTS

The presence of severe uveitis at presentation was a significant predictor of a final visual acuity of less than 6/60 (p = 0.002). A raised intraocular pressure at presentation (> 29 mmHg) significantly increased the risk of chronic glaucoma (p = 0.0279), but there was no association between glaucoma and delay in vitrectomy. Patients operated on within 1 week of cataract surgery obtained a better visual outcome (64.7%) of patients achieved 6/12 or better visual acuity) than those operated on later than 1 week (41% obtained 6/12), but this difference did not reach statistical significance.

CONCLUSIONS

The trend towards a better visual outcome with early vitrectomy was not statistically significant. A large prospective trial is indicated to determine the optimum time for vitrectomy in these patients.

Phacoemulsification of a nucleus in the vitreous cavity

Loss of the crystalline lens into the vitreous cavity can lead to corneal damage and expulsive hemorrhage. In this technique, the lens is released from adhesions by vitrectomy and then extracted from the vitreous cavity by phacoemulsification using a special tip. No protective liquids are used to cover the retina. This technique was successful in 44 patients.

Outcomes of dropped nucleus during phacoemulsification

PURPOSE

To evaluate the clinical outcome of vitrectomy in the management of dropped nucleus during phacoemulsification.

METHOD

Twenty-five consecutive patients who underwent pars plana vitrectomy for the management of dropped nucleus from phacoemulsification, over a 36-month period, were studied. Twenty-two patients underwent vitrectomy within 15 days of cataract surgery. Most of the patients were followed for more than 6 months.

RESULTS

Final visual acuity was 20/40 or better in 71% (17/24) of eyes and 20/50 in 8% (2/24). Visual acuity was 20/70 or worse in 21% (5/24) of patients. Complications included persistent cystoid macular edema in three eyes, epimacular proliferation in two eyes, and a choroidal detachment in one eye.

CONCLUSION

Poor visual outcome after dropped nucleus at phacoemulsification cataract extraction can be avoided if managed by prompt pars plana vitrectomy.