Plate-haptic Intraocular Lens Research Articles

Rotational stability and posterior capsule opacification of a plate-haptic and an open-loop-haptic intraocular lens

To compare the rotational stability and posterior capsule opacification (PCO) rate in eyes with a 1-piece or 3-piece acrylic intraocular lens (IOL). Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. Prospective randomized masked clinical trial. Patients with age-related cataract received a plate-haptic acrylic IOL (Acri.Smart 46S) in 1 eye and a 3-piece loop-haptic acrylic IOL (Acri.Lyc 53N) in the other eye. Retroillumination images were taken 1 hour, 1 week, and 1, 6, and 12 months postoperatively. Intraocular lens rotation was measured using standard software (Adobe Photoshop). The amount of PCO was assessed subjectively at the slitlamp and objectively using an automated image-analysis software (AQUA). The study enrolled 80 eyes of 40 patients. The IOL rotation measurements showed excellent reproducibility, with a deviation of less than 0.8 degrees. Both IOLs had comparable and good rotational stability; rotation was less than 4 degrees in 71% of eyes 1 year postoperatively. The mean absolute rotation was 2.6 degrees ± 1.9 (SD) in the plate-haptic IOL group and 3.1 ± 2.4 degrees in the loop-haptic IOL group. The mean AQUA PCO score (scale 0 to 10) was 0.4 in both IOL groups (P = .7). The 2 IOL models had comparable, excellent rotational stability and low PCO intensity 1 year postoperatively. Thus, the plate-haptic IOL may be a good platform for a toric model.

Bilateral recurrent dislocation of plate haptic intraocular lens

Bilateral recurrent dislocation of plate haptic intraocular lens

Late posterior subluxation of rollable intraocular lens after an uneventful microphacoemulsification cataract surgery

Dear Editor, We report a rare complication of late posterior subluxation of rollable intraocular lens (IOL) after an uneventful microphacoemulsification cataract surgery. A 60-year-old non-diabetic, non-hypertensive male patient was operated for microphacoemulsification, phaco chop technique for senile cataract in the right eye using 0.9 mm limbal incision which was enlarged to 1.5 mm and an acrylic rollable IOL (micriol, Eyeol, UK, optic size: 5.0 mm, overall length: 11.0 mm) was implanted in the bag. The patient regained 20/20 vision (on Snellen's chart) at the end of six weeks of follow-up and had no complaints. Then after three months the patient returned with decrease in vision in the right eye (20/200). The slit-lamp examination revealed posterior capsular opacification with shrinkage of anterior capsule. Patient underwent uneventful YAG capsulotomy (around 2 mm diameter). Patient regained 20/20 vision at two weeks follow-up. However, two months later, patient returned with painless progressive diminution of vision (finger counting at 2 meters) with glare and uniocular diplopia. There was no history of trauma. The slit-lamp examination [Fig. 1] and ultrasound biomicroscope [Fig. 2] demonstrated posterior subluxation of the rollable IOL with vitreous prolapsed in the anterior chamber. The patient was subjected to IOL exchange procedure and anterior vitrectomy. The rollable IOL was explanted through the scleral tunnel and a rigid polymethyl methacrylate (PMMA) lens was implanted in the sulcus. The patient regained 20/20 vision on the next follow-up.Figure 1: Anterior segment showing posterior subluxation of the rollable IOL and shrinkage of anterior capsuleFigure 2: UBM demonstrating posterior subluxation of the rollable IOL with vitreous prolapsed in anterior chamberMicroincisional cataract surgery is a safe procedure with a very short learning period for an experienced cataract surgeon and rollable ultrathin IOLs eliminate the need for enlargement of corneal incision.[1] However, the rollable IOLs having plate haptics have their own set of problems. The posterior dislocation of the plate haptic IOL has been known to occur after Nd:YAG capsulotomy.[2] Even the anterior luxation of plate haptic IOL has been reported.[34] It has been postulated that the shrinkage of the anterior capsule exerts centripetal forces on the ends of the plate haptics, causing the optic to move posteriorly and to exert pressure against the posterior capsule. If either the posterior or anterior capsule is disrupted by Nd:YAG laser treatment, the forces created by capsular contraction against the flexible lens may cause extension of radial tears and appear to be a substantial risk for further capsule-tearing, releasing the IOL into the vitreous cavity, even months later. The forces of capsular contraction can impart a spring-loading effect on plate haptic silicone lenses. Due to inadequate capsular adherence, these lenses are at risk of posterior dislocation from capsular rents following Nd:YAG laser treatment.[5] It is important to have a close follow-up of patients with plate haptic rollable IOLs undergoing YAG capsulotomy. Patients should be warned of this rare possible complication. Vitrectomy and IOL exchange with rigid PMMA lens implantation in the sulcus seems to be effective in tackling this complication.

Scleral Fixation of a Silicone Plate Haptic Intraocular Lens in a Patient Showing Repeated Pupillary Intraocular Lens Capture

A 39-year-old man with Marfan syndrome underwent scleral fixation using a three-piece foldable intraocular lens and experienced repeated pupillary intraocular lens captures secondary to a pliable iris. As a result, the patient needed an additional pupilloplasty. In the opposite eye, a silicone plate haptic intraocular lens was used for scleral fixation because it was thought that the plate design could prevent pupillary intraocular lens capture, even in cases involving a pliable iris. At the 27-month follow-up examination, the patient showed good centration of the intraocular lens in the eye that used the silicone plate haptic intraocular lens without pupillary intraocular lens capture.

Anterior luxation of rollable intraocular lens

Dear Editor, Bimanual microincisional phacoemulsification surgery is a safe procedure with a very short learning period for an experienced cataract surgeon and rollable ultrathin intraocular lenses eliminate the need for enlargement of corneal incision.1 We report a rare case of late anterior subluxation of rollable plate haptic intraocular lens following an uncomplicated surgery. A 63-year-old female patient was operated for right eye cataract surgery by bimanual microphacoemulsification using stop and chop technique and an acrylic rollable plate-haptic intraocular lens (Micriol, Eyeol, UK) was implanted in the bag. The surgery was uneventful. The size of the capsulorhexis was small and so at the end of the procedure a relaxing incision was made on the superonasal part of the anterior capsule to prevent capsular phimosis. Postoperatively, the patient had best corrected visual acuity of 20/20 (on Snellen) at six weeks. Three months postoperatively; the patient came back with complaint of decreased vision in the operated eye. The patient had no history of trauma to the eye and the symptoms of blurred vision developed spontaneously over a period of few days. On examination, the visual acuity was reduced to 20/200. The slit-lamp examination revealed anterior subluxation of the nasal part of the lens with peaked pupil [Fig. 1]. This resulted in an unacceptably high astigmatic error. The patient was posted for dialing of the lens under topical anesthesia and the lens was dialed back in the bag with haptic lying away from the relaxing incision. Following the procedure the patient regained her best-corrected vision of 20/20 from day 1 and has continued to maintain her vision.Figure 1: Anterior subluxation of plate-haptic intraocular lens with peaked pupilThe posterior disclocation of the plate haptic intraocular lens has been known to occur after Yag capsulotomy.2 Anterior subluxation of the plate haptic lens is rare but has been reported in the past.3 A thin plate haptic rollable intraocular lens can get subluxated in the anterior chamber through the relaxing incision of the anterior capsulorhexis. Therefore an intact continuous curvilinear capsulorhexis and in the bag implantation is essential to prevent such a complication.

Hyperopic shift with posterior bowing of a Collamer posterior chamber intraocular lens

Two patients developed a hyperopic shift following uneventful phacoemulsification with implantation of a Collamer plate-haptic intraocular lens (Staar Surgical) in the capsular bag. Posterior bowing of the IOL was corrected by IOL exchange, achieving near emmetropia.

Two-string technique to manage dislocated posterior chamber plate-haptic intraocular lens

We describe a technique for repositioning and transscleral fixation of a dislocated plate-haptic foldable collamer posterior chamber intraocular lens (PC IOL). The displaced IOL was positioned in the anterior chamber, and a double-armed suture on a curved needle was fixed to the sclera at 10:30 o'clock. The needle then entered the globe and passed through the superior haptic eyelet of the IOL. Both were withdrawn through the scleral wound on the opposite side. The inferior haptic was fixed at 4:30 and 7:30 o'clock and provided the mirror reflection of the suture path of the upper fixed haptic. This technique may be a useful alternative to lens removal or exchange.

Long-Term Safety and Efficacy of Repositioning Dislocated Plate Haptic Intraocular Lenses in the Ciliary Sulcus

To report safety and efficacy outcomes of repositioning posterior dislocated plate haptic lenses (PHLs) in the ciliary sulcus (CS). Retrospective interventional case series. Fifteen consecutive eyes with dislocated PHL repositioned in the CS were reviewed retrospectively. Pars plana vitrectomy was required in 12 of 15 cases. The main outcome variables were initial and final best-corrected visual acuity (BCVA) and length of follow-up. All lenses remained centered for an average of 48.7 months (range 4 to 99 months) of follow-up with no recurrent dislocation, cystoid macular edema, chronic iritis, or iris chaffing. Initial and final BCVA of 20/40 or better was attained in 93.3% (14 of 15) and 66.7% (10 of 15) of eyes, respectively. Decline of final BCVA was attributable to secondary eye diseases and not related to repositioning. Our study reports dislocated PHL may be managed safely and effectively by placement in the CS with long-term stability under certain clinical scenarios.

Pilocarpine-induced shift of an accommodating intraocular lens: AT-45 Crystalens

To measure the shift of an accommodating plate-haptic intraocular lens (IOL) along the visual axis induced by ciliary muscle contraction after application of pilocarpine. Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. Fifty-four eyes of 28 patients with age-related cataract comprised this prospective study. Each patient received an AT-45 silicone accommodating IOL (Crystalens, Eyeonics Corp.) after standardized cataract surgery. In a subgroup of 24 eyes, capsular bag fibrosis was reduced by extensive polishing of the anterior capsule with a slit cannula. Assessment included measurements of anterior chamber depth, assessed with partial coherence interferometry, before and after application of pilocarpine 2% and evaluation of near visual acuity 1 month and 3 months postoperatively. A slight backward shift of the IOL of 151 mum in the nonpolished group (P < .001) and 122 mum in the polished group (P < .005) could be detected after application of pilocarpine. Polishing the capsule did not influence IOL shift. The median near visual acuity with distance correction 1 month and 3 months postoperatively was J5 and J4, respectively, in the nonpolished group and J6 at both times in the polished group. Pilocarpine induced a counterproductive active backward shift of the AT-45 IOL. Polishing of the capsular bag had no impact on accommodative ability. The reading performance of patients with the AT-45 IOL patients at 1 and 3 months was not significantly different from that of with a standard IOL under similar testing methods.

Early rotational stability of the longer Staar toric intraocular lens: fifty consecutive cases

Purpose To determine whether rotational stability is improved with the longer Staar toric intraocular lens (IOL). Setting A private practice, Los Altos, California, USA. Methods Staar Surgical manufactures toric plate-haptic IOLs under +24.0 diopters (D) in 2 lengths. Fifty consecutive eyes requiring toric IOL spherical powers less than +24.0 D received the longer toric IOL (TL; 11.2 mm) using a specific surgical protocol. The IOL axis was recorded at 1 day, 1 week, and a final follow-up visit. Five additional eyes requiring powers greater than +24.0 D received the shorter toric IOL (TF; 10.8 mm), which is the only available length in these powers. Results were compared with those in an initial consecutive series of 6 eyes having implantation of the TF IOL with a power less than +24.0 D before the TL model became available. Results Rotational stability of all 50 TL IOLs and the 5 TF IOLs of higher dioptric powers was excellent. One IOL rotated as much as 20 degrees off axis. The repositioning rate was zero in both groups. In the initial 6 eyes receiving the shorter toric IOL in powers below +24.0 D, the repositioning rate was 50%. Conclusions The longer toric IOL had excellent early rotational stability. Rotational and repositioning rates with the TL IOL were superior to those in a previous series of the TF IOL. Adequate overall length is a critical factor in the rotational stability of plate-haptic toric IOLs, and the longer IOL should be used when available.

Silicone plate-haptic lens injection without prior incision enlargement

Injection devices are routinely used to implant silicone plate-haptic intraocular lenses (IOLs). The injector cannula is normally introduced directly into the anterior chamber prior to injection, either after deliberate wound enlargement or by forcible entry with significant wound stretching. We present a technique for injecting the lens through the wound in which apposition is maintained between the injector tip and the unenlarged phaco incision. In 25 eyes, the wound enlarged after IOL implantation by a mean of 0.13 mm ± 0.05 (SD), representing a 4.0% increase in width. We have found this modified technique to be safe, effective, and reproducible.

Dislocation of a plate-haptic silicone intraocular lens into the anterior chamber

Posterior dislocation is a well-described complication of plate-haptic intraocular lenses (iols). it usually occurs after an opening in the posterior capsule, either intraoperatively or after a neodymium YAG capsulotomy occurs. We report a case of anterior luxation of a plate-haptic silicone IOL occurring 4 months after uneventful cataract surgery. This case emphasizes the need for a small and continuous capsulorhexis as well as in-the-bag implantation of plate-haptic IOLs.

Effect of large positioning holes on capsule fixation of plate-haptic intraocular lenses

Purpose To compare the centration and fixation of silicone plate-haptic intraocular lenses (IOLs) with different-sized positioning holes. Setting Eye Clinic of the Johannes Gutenberg-University Mainz, Mainz, Germany. Methods In a prospective randomized study, 51 Chiroflex C10 and 56 Chiroflex C11 IOLs were implanted under standardized conditions by the same surgeon. The IOL position was documented at the end of surgery and by retroillumination on the first day and 5 months postoperatively. The positioning-hole area was evaluated by ultrasound biomicroscopy (50 MHz) 5 months postoperatively. Results One day postoperatively, no IOL in either group was decentered more than 1.0 mm. After 5 months, 33% of the C10 and 42% of the C11 IOLs were decentered between 0.5 and 1.0 mm, and 11% of the C10 and 8% of the C11 IOLs were decentered more than 1.0 mm (maximum 1.23 mm and 1.41 mm, respectively). Up to the first postoperative day, 20% of the C10 and 22% of the C11 lenses were rotated more than 15 degrees. At 5 months, an additional 15% of the C10 and 19% of the C11 lenses were rotated. Ultrasound biomicroscopy showed no tissue or capsule adhesion in the holes in most cases (85% C10 group; 71% C11 group). No difference was statistically significant. Conclusions Larger positioning holes did not prevent IOL decentration or rotation; thus, this IOL design appears unsuitable for correcting astigmatism. Because tissue in the positioning hole was rare with both lens types, it is doubtful that enlarged plate-haptic perforations will prevent IOL luxation into the vitreous cavity after capsulotomy.

Delayed posterior dislocation of silicone plate-haptic lenses after neodymium:yag capsulotomy

We report 4 cases of posterior dislocation of silicone plate-haptic intraocular lenses (iols) into the vitreous cavity occurring a mean of 16 months after neodymium:YAG laser posterior capsulotomy. In each case, no peripheral capsule defect was observed at the time of laser capsulotomy or at subsequent follow-ups. One case was treated with sulcus implantation of a 3-piece IOL, with the plate-haptic IOL left in the vitreous cavity. The other cases were managed with vitrectomy (2 pars plana, 1 anterior) to remove the plate-haptic lens with subsequent sulcus placement of a 3-piece IOL. Patients should be informed that posterior dislocation is an infrequent but possible complication of these lenses and may occur months and even years after implantation or laser capsulotomy.

Factors leading to lens implant decentration and exchange.

To examine the intra- and post-operative factors leading to posterior chamber intraocular lens (IOL) decentration in patients requiring IOL exchange, and to identify avoidable causes of IOL decentration. Case records of 17 patients who had undergone posterior chamber IOL exchange were examined for: (i) any complication or alteration to the original intended surgical procedure, (ii) IOL type and position at the completion of initial surgery, (iii) IOL position at the time of re-operation. The decentred lens implants were injected silicone plate-haptic IOLs in 10 patients, small (5.5 mm) optic diameter PMMA IOLs in 4 patients and large (7 mm) optic diameter PMMA IOLs in 3 patients. In all cases, decentration was due to IOL subluxation. Early decentration of the injected lenses was due to IOL implantation in eyes without a continuous capsulorrhexis. In contrast late decentration was due to subluxation associated with capsule fibrosis. Decentration of small optic PMMA IOLs was found to be associated with an anterior capsule tear and haptic malposition in the ciliary sulcus. Decentration of large optic PMMA IOLs was associated with posterior displacement of one haptic through a posterior capsule defect, zonule dehiscence or fixation of one haptic in the sulcus and one in the capsule bag. Clinically significant post-operative subluxation of injected silicone IOLs may be minimised by implanting only into a lens capsule bag with an intact capsulorrhexis. The risk of decentration of small optic PMMA IOLs may be minimised by positioning the haptics at 90 degrees to any capsulorrhexis tear. After cataract surgery complicated by posterior capsule rupture or zonule dehiscence, it is important to assess the remaining capsule support and, where sufficient, implant a large optic diameter posterior chamber IOL in the ciliary sulcus.

Postoperative intraocular lens rotation: A randomized comparison of plate and loop haptic implants

Objective To compare the postoperative rotation of plate and loop haptic implants of spherical power to ascertain the optimal design appropriate for toric intraocular lenses (IOLs). Design Randomized, controlled trial. Participants Forty-eight patients attending for routine cataract surgery by phacoemulsification. Method Patients with cataract as the only ocular disease were randomly implanted with plate or loop haptic implants after uncomplicated phacoemulsification. The baseline position of the IOL was determined from a video frame acquired at the conclusion of surgery. Postoperative IOL position was documented using digital retroillumination images at 2 weeks and 6 months after surgery. Capsular fusion patterns were recorded using slit-lamp biomicroscopy. Correlation of IOL rotation with axial length, capsular contraction, and fusion was attempted. Main outcome measures Early IOL rotation, occurring between surgery and 2 weeks after surgery, was graded as mild (<10°), moderate (10°< to <30°), or severe (>30°) by a semiobjective online comparison of the images. Late IOL rotation, occurring between 2 weeks and 6 months, was measured more precisely using software developed specifically for the study. Results Twenty-three patients were allocated the loop haptic and 25 the plate haptic IOL. The groups were comparable for demographic variables and numbers of patients excluded from analysis ( P > 0.05). Five (24%) of 21 of plate haptic IOLs underwent severe early rotation compared to 2 (9%) of 22 loop haptics ( P = 0.36). The median late rotation was 6.8° for loop haptics compared to 0.6° for plate haptics ( P = 0.0073). Between 2 weeks and 6 months, anticlockwise rotation had occurred in 16 (89%) of 18 loop haptic IOLs compared to 11 (52%) of 21 plate haptic IOLs ( P = 0.0081). Conclusions Plate haptic IOLs show greater rotational stability than do loop haptics made from polypropylene once capsular fusion has taken place. Loop haptics invariably rotate anticlockwise after 2 weeks.

Explantation of Silicone Plate Haptic Intraocular Lenses

The stress on small self-sealing incisions in cataract surgery has resulted in the increased use of foldable intraocular lenses (IOL). Plate haptic silicone IOLs implanted with the help of an injector require extremely small incision lengths and are extensively used. The authors discuss difficulties in explanting such lenses, especially in inflamed eyes. Two patients who underwent plate-haptic silicone IOL explantation for postoperative bacterial endophthalmitis are described. Plate haptic IOLs have a tendency to dislocate posteriorly because of poor capsular fixation and increased posterior bowing. Enlarging a small rhexis prior to attempting explantation of these lenses reduces this complication. Difficulties inherent in explanting plate haptic silicone IOLs in inflamed eyes are discussed, along with suggestions to overcome them.

Complete capsulorhexis opening occlusion despite capsular tension ring implantation

An 89-year-old woman and an 86-year-old woman had continuous curvilinear capsulorhexis, phacoemulsification, and implantation of a silicone plate-haptic intraocular lens. Because of presumed weak zonules (high age, pseudoexfoliation), a poly(methyl methacrylate) capsular tension ring was also implanted. Despite this, both patients reported deterioration in visual acuity that was the result of complete occlusion of the anterior capsule opening by fibrotic tissue 4 and 3 months postoperatively, respectively.

Changes in intraocular lens position after neodymium:YAG capsulotomy

Purpose To quantify changes in intraocular lens (IOL) position caused by neodymium:YAG (Nd:YAG) capsulotomy with 3 IOL styles. Setting Department of Ophthalmology, University of Vienna, Austria. Methods In a prospective study, anterior chamber depth (ACD) was measured by dual-beam partial coherence interferometry (PCI) in 32 pseudophakic eyes of 32 patients with posterior capsule opacification before and immediately after planned capsulotomy under mydriasis. Patients were divided into 3 groups with the following IOL styles: 1-piece poly(methyl methacrylate) (PMMA), 3-piece foldable, and plate haptic. Results The capsulotomy induced a backward IOL movement in all 32 eyes (mean 25 μm; range 9 to 55 μm). It was more pronounced in eyes with plate-haptic IOLs than in those with the other styles. Precision of ACD measurement by PCI was 4 μm. Changes in ACD correlated significantly with capsulotomy size but not with preoperative lens–capsule distance. Conclusion Capsulotomy caused a backward movement of the IOL, which was more pronounced with plate-haptic IOLs than with 1-piece PMMA and 3-piece foldable IOLs. Since the magnitude of IOL movement in this study population was small, a hyperopic shift in refraction after capsulotomy will usually be small and not clinically relevant.

Decentration of 3-piece versus plate-haptic silicone intraocular lenses

Purpose: To compare the incidence of decentration with 2 types of silicone intraocular lenses (IOLs).Setting: John A. Moran Eye Center, University of Utah Medical Center, Salt Lake City, Utah, USA.Methods: Selection criteria for this retrospective study included patients who had uncomplicated cataract surgery with a clear cornea or seieral tunnel incision with a curvilinear capsulorhexis and capsular bag implantation of a silicone IOL. After a mean follow-up of 14 months (range 12 to 18 months), 54 eyes implanted with a 3-piece lens (AMO SI-30) and 58 eyes implanted with a plate-haptic lens (Staar AA403) were examined for posterior chamber IOL decentration. The decentration criterion was 0.5 mm or more from the center of the pupil. Detailed chart review of preoperative and postoperative measurements was performed for each patient.Results: Eighteen of the 3-piece IOLs (33%) and 11 of the plate-haptic IOLs (20%) were decentered 0.5 mm or more (P = .129). Using photographic analysis, the mean IOL decentration with the 3-piece IOL (1.12 mm ± 0.198 [SD]) was significantly greater than with the plate-haptic IOL (0:632 ± 0.278 mm) (P < .001). No statistically significant correlation was found between the centered or decentered IOL groups' preoperative refraction, axial length, capsulorhexis size, type of incision, or rate of neodymium:YAG laser capsulotomy.Conclusions: No statistically significant difference was seen between the decentration rates of 3-piece and plate-haptic IOLs; however, the amount of decentration with the 3-piece IOL was significantly greater than with the plate-haptic IOL. Other factors did not contribute to IOL decentration.