Scleral Fixation Re-examined by Ultrasound Biomicroscopy

Complications of Scleral-Fixated Intraocular Lenses

INTRODUCTION

Understanding the evolution of complications after scleral-fixated lens placement demonstrates advantageous surgical techniques and suitable candidates.

MATERIALS/METHODS

A literature search in PubMed for several terms, including "scleral intraocular lens complication," yielded 17 relevant articles.

RESULTS

Reviewing complication trends over time, lens tilt and suture erosion have decreased, cystoid macular edema has increased, and retinal detachment has remained the same after scleral-fixated lens placement. The successful reduction in complications are attributed to several alterations in technique, including positioning sclerotomy sites 180 degrees apart and using scleral flaps or pockets to bury sutures. Possible reduction in retinal risks have been proposed by performing an anterior vitrectomy prior to lens placement in certain settings.

DISCUSSION

Complications after scleral-fixated lens placement should assist patient selection. Elderly patients with a history of hypertension should be counseled regarding risk of suprachoroidal hemorrhage, while young patients and postocular trauma patients should be considered for concurrent anterior vitrectomy.

In vivo analysis of glued intraocular lens position with ultrasound biomicroscopy

PURPOSE

To report ultrasound biomicroscopic (UBM) findings of glued transscleral-fixated posterior chamber intraocular lenses (IOLs) in eyes with inadequate capsules.

SETTING

Dr. Agarwal's Eye Hospital and Eye Research Centre, Chennai, India.

DESIGN

Case series.

METHODS

Eyes with glued IOLs for inadequate capsule support were examined with UBM. Optic tilt was measured in relation to the iris plane. Haptic location, iris-IOL contact, vitreous incarceration, and central anterior chamber depth (ACD) were measured and correlated clinically with vision and refractive error.

RESULTS

The mean follow-up was 24.6 months ± 14.3 (SD). Of the 46 eyes, 8 (17.4%) showed optic tilt and 38 (82.6%) showed no optic tilt. Of 92 haptics examined, 85 (92.4%) were in the ciliary sulcus and 7 (7.6%) in the pars plicata. There was no significant association between the presence of optic tilt and haptic location (P=.585, chi-square test). The mean ocular residual astigmatism (ORA) was 0.5 ± 0.2 diopter (D). There was no significant difference in ORA between eyes with tilt and eyes without tilt (P=.079). There was no significant correlation between ORA and IOL position. There was no correlation of optic tilt and postoperative vision or cylinder. Other features included iris-IOL contact (6.5%), vitreous incarceration (5.4%), and ACD difference (P=.002).

CONCLUSIONS

No significant IOL optic tilt affecting the postoperative vision was detected with glued transscleral-fixated IOLs. The technique reliability was good, with the haptics located in the intended position in more than 90% of eyes.

FINANCIAL DISCLOSURE

Dr. Amar Agarwal is a paid consultant to Staar Surgical Co. No other author has a financial or proprietary interest in any material or method mentioned.

Scleral fixation in eyes with loss of capsule or zonule support

We describe a new scleral fixation technique for posterior chamber intraocular lens (IOL) implantation in eyes with partial or total loss of the posterior capsule or zonule support. This technique uses a scleral incision that can be completed in less time than a conventional scleral flap and prevents unnecessary trauma to the eye. A double-thread, 10-0 polypropylene suture loop is introduced once through a scleral layer pathway inside the eye. The free ends of the polypropylene suture are buried between the 2 edges of the scleral incision. This technique was used in 15 eyes, with a follow-up of 6 to 30 months. Complications included iris capture, irregular pupil, hyphema, vitreous hemorrhage, choroidal hemorrhage, localized peripheral anterior synechias, and retinal detachment. The mean postoperative visual acuity was 20/40 at the last follow-up. This modified technique is an easy and effective way to achieve scleral fixation of the IOL.

Evaluation of a new IOL scleral fixation technique without capsular support

PURPOSE

The purpose of this study was to compare a new intraocular lens (IOL) scleral fixation technique (scleral incision) with the scleral flap surgical technique as regards to efficacy, surgical complications, advantages, disadvantages, and surgery costs in cases with no capsular support.

MATERIAL AND METHODS

This was a retrospective study conducted on thirty patients (30 eyes), ten of whom were aphakic, eleven had traumatic cataract, seven had post-phacoemulsification complications, and two had lens luxation. The patients were divided into two groups (I - scleral incision technique and II - scleral flap technique) of fifteen patients each, during a study period lasting eighteen months. The great majority of the procedures were performed under general anesthesia and by the same surgeon. Statistical analysis was done using SPSS. The numerical variables were compared using the t test and the categorical ones using the Fisher exact test. We performed multifactorial analysis to build a model that could predict and compare the complications associated with each technique. An explicative model was built using logistic regression.

RESULTS

We observed a threefold higher rate of complications associated with the scleral flap technique when compared to the scleral incision technique. This difference was particularly relevant as regards the occurrence of free scleral flap and hyphema. No statistically significant differences were observed regarding vitreous hemorrhage, choroidal hemorrhage, retinal detachment, difficulty in the external pulling of the Prolene suture, breaking of the Prolene suture, and anterior chamber collapse. We found a significant association between intraoperative complications and the technique used (higher number of complications with the scleral flap) and also with some systemic diseases (patients with hypertension had more intraoperative complications). The number of late complications resulting from the scleral flap technique was much higher than those observed with the scleral incision technique; however, the number of the cases we studied is insufficient to reach statistical significance.

CONCLUSION

The duration of the procedure using the IOL scleral incision technique is significantly lower than using the scleral flap technique. Intraoperative complications were significantly associated with the technique used: more frequent with scleral flap. Late complications were mainly associated with systemic and previous ocular diseases.

Techniques of intraocular lens suspension in the absence of capsular/zonular support

Implantation of intraocular lenses has become the standard of care in the aphakic state. Ideally, the lens is placed in the capsular bag, which affords stable fixation at a position closest to the nodal point of the eye. However, there will always be instances where this will not be possible. Congenital weakness of the lens zonules in various conditions, trauma, and surgical complications of cataract surgery are just some examples. In this article, we review the methods that have been devised to allow intraocular lens implantation in the absence of capsular or zonular support. These include anterior chamber angle and iris-fixated lenses, as well as posterior chamber iris- and scleral-sutured lenses. The various lenses are described, and the techniques involved, advantages and disadvantages, complications, and results of each method are discussed. It is hoped that this article will provide a comprehensive overview of ways to deal with a problem that can still result in a very good visual outcome for the patient. This is particularly relevant given the many recent developments and refinements of methods in implanting intraocular lenses.

Ultrasound biomicroscopy of haptic position after transscleral fixation of posterior chamber intraocular lenses

PURPOSE

To determine the haptic position of ab externo transsclerally fixated posterior chamber intraocular lenses (PC IOLs) by ultrasound biomicroscopy (UBM).

SETTING

Mansoura Ophthalmic Center, Mansoura University, Mansoura, Egypt.

METHODS

Ultrasound biomicroscopy was used to determine the haptic position in relation to the ciliary sulcus, iris, and ciliary body in 20 patients with transsclerally fixated PC IOLs. The patients ranged in age from 10 to 65 years.

RESULTS

All IOL haptics were easily visualized and imaged by UBM. Of the 40 IOL haptics, 22 (55.0%) were located in the sulcus, 11 (27.5%) anterior to the sulcus, and 7 (17.5%) posterior to the sulcus region.

CONCLUSIONS

Ab externo scleral fixation of PC IOLs is a blind procedure in most cases. Ultrasound biomicroscopy showed the difficulty in reliably placing the haptics in the ciliary sulcus using this technique. Thus, endoscopic visualization of the iridociliary angle during surgery is recommended.

Endoscopic technique for suturing posterior chamber intraocular lenses

A challenge of the sutured posterior chamber intraocular lens (IOL) technique is to perform blind actions behind the iris. To avoid imprecise transscleral sutures and complications, we use an endoscopic procedure with 2 goals: to control the entry site of the needle penetration and of the haptic location. The endoscopic technique allows retroiris control during transscleral suturing and iridociliary IOL implantation. It is a safe, precise method that avoids the risks of blind procedures behind the iris.

Intraocular lens tilt and decentration, anterior chamber depth, and refractive error after trans-scleral suture fixation surgery

OBJECTIVES

To compare the extent of intraocular lens (IOL) tilt and decentration, as well as the anterior chamber depth after trans-scleral suture IOL fixation after either secondary out-of-the-bag or primary in-the-bag IOL implantation.

DESIGN

Retrospective, comparative, nonrandomized, interventional study.

PARTICIPANTS

Fifty-two eyes that underwent scleral suture fixation were compared with 51 eyes that underwent secondary out-of-the-bag implantation and 50 eyes that underwent in-the-bag implantation.

INTERVENTION

One-piece polymethyl methacrylate IOL implantation by three different techniques.

MAIN OUTCOME MEASURES

The tilt angle and decentration length of the IOL, as well as the anterior chamber depth, were measured by the Scheimpflug videophotography system. The spherical equivalent error from the predicted value was also examined.

RESULTS

The mean tilt angle in the scleral suture fixation group was significantly greater than that in either the out-of-the-bag or the in-the-bag implantation group (P<0.0001). The mean decentration length was also largest in the suture group, followed by the out-of-the-bag group and the in-the-bag group (P<0.0001). The anterior chamber depth in the suture group and the out-of-the-bag group was significantly smaller than that in the in-the-bag group (P<0.0001). The spherical equivalent error in the suture group and the out-of-the-bag group was also greater than that in the in-the-bag group (P<0.0001).

CONCLUSIONS

The extent of both tilt and decentration after scleral suture fixation was greater than that observed after either out-of-the-bag or in-the-bag implantation. The anterior chamber depth with the sutured or out-of-the-bag fixated IOL was shallower than that with the in-the-bag fixated IOL, which resulted in a significant myopic shift.

Secondary implantation of scleral-fixated intraocular lenses

PURPOSE

To evaluate the results of a large series of secondary implantations using scleral-fixated posterior chamber intraocular lenses (IOLs).

SETTING

Bellevue Eye Hospital, Kiel, Germany.

METHODS

This retrospective review comprised 624 consecutive patients who had secondary implantation of a posterior chamber IOL with scleral fixation between 1988 and 1995. All patients had been aphakic for at least 1 year. An ab interno or ab externo suture technique through the ciliary sulcus was used. Visual outcome and complications 1 year after surgery were determined.

RESULTS

Best corrected visual acuity improved or remained unchanged in 92.0% of eyes; 8.0% lost one or two lines. Intraocular lens decentration of more than 1.5 mm occurred in 1.9% of eyes. Suture erosion was observed in 17.9%, cystoid macular edema in 5.8%, retinal detachment in 1.4%, and vitreous hemorrhage in 1.0%. Severe uveitis occurred in 0.5%.

CONCLUSION

Secondary IOL implantation with scleral fixation was a safe procedure. Although there was a small risk of significant complications, more than 90% of patients regained or improved their preoperative visual acuity.

Sutureless scleral fixation of intraocular lenses

A technique is presented in which pars plana fixation of a posterior chamber intraocular lens (IOL) is achieved by the transscleral passage of the haptics. The IOL used has three equidistant supple loops, each attached to an armed suture, which serve as haptics. A specially designed needle driver is used to pass the sutures into and out of the eye through the pars plana and along the surface of the sclera, where they are severed by cautery. Stable fixation is achieved without contact with the inner tissues of the eye, and no additional sutures are necessary. Lens stability is maintained even in the presence of asymmetrical fibrosis of the capsular remnants.