IOL Placement Research Articles

Results with a modified method for scleral suturing of intraocular lenses.

The long-term results obtained by a modified method of scleral suturing of posterior chamber lenses (PCLs) (Behndig & Otto 1997) were retrospectively registered and evaluated. Forty-four patients with insufficient capsular support for ordinary PCL implantation were included. Mean follow-up time was 13.1 +/- 6.4 months and registered parameters included visual acuity, deviation from planned refractive outcome, induced astigmatism, and complications. The results were comparable to those reported earlier for this type of surgery. It has previously been stated that scleral suturing of posterior chamber lenses is a safe procedure with good long-term results. This modified method produces comparable results while being more surgically simple and reproducible.

Older age as risk factor for deviation from emmetropia in pseudophakia.

To find risk factors for deviation from emmetropia after cataract surgery in clinical practice. We evaluated the refractive outcome in 106 patients who had underone phacoemulsification and in-the-bag IOL placement 115 +/- 10 days after surgery. Postoperative optical correction and refractive error (diopters of spherical equivalent--ED) were related to age and sex, pre-operative axial length and keratometric diopter power, and operative incision technique. Emmetropia was achieved in 15% of cases; 65% of eyes needed a myopic correction, averaging = 0.46 +/- 0.91 ED. The refractive error was 0.74 +/- 0.61 ED (< or = 1 ED in 77% of cases, < or = 2 ED in 97%). Both optical correction and refractive error were correlated to older age at the time of surgery (p=0.002 and p=0.001, respectively). Astigmatism appeared greater in clear-cornea incision than in limbar incision cases (p=0.05). The higher refractive error in patients aged over 73 years suggests that age may be a risk factor for deviation from emmetropia after cataract surgery.

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.

Intraocular lens explantation in uveitis.

Visual rehabilitation after cataract surgery has been improved with the development of IOLs. These lenses are well tolerated in many uveitis patients when complete control of preoperative inflammation is achieved. However, in some patients, IOL placement after cataract extraction results in chronic inflammation, deposition of inflammatory cells and debris on the IOL surface, and inflammatory membrane formation despite antiinflammatory coverage. Patients with systemic diseases characterized by chronic inflammation, such as sarcoidosis and JRA, and those with chronic ocular inflammatory conditions or inflammation involving the intermediate segment of the eye may be at high risk for these complications. In patients in whom antiinflammatory therapy fails, adequate control of inflammation may be achieved after lens explantation.

Incidence of retinal detachment following Nd:YAG capsulotomy after cataract surgery

In a retrospective study, we reviewed 218 consecutive Nd:YAG laser posterior capsulotomies performed at the Gimbel Eye Centre between June 1987 and November 1989 for the incidence of retinal detachment (RD) following treatment. Matched controls were found for 198 YAG cases. The median post-surgical follow-up for the YAG cases was 49.5 months; for the controls, 50.0 months. The median time between cataract extraction and YAG laser posterior capsulotomy was 24.8 months. The median follow-up after YAG was 24.2 months. Two of the 198 YAG cases (1.0%) and one of the 198 controls (0.5%) had RD. In the YAG cases, RD occurred 54.8 and 36.5 months after cataract surgery; in the control cases, 51.8 months after cataract surgery. Retinal detachment occurred at 15.0 and 17.0 months after YAG capsulotomy. These rates were lower than those reported in the literature. We feel that the surgical techniques of continuous circular capsulorhexis and in-the-bag IOL placement reduce the risk of RD following Nd:YAG posterior capsulotomy.

Posterior Chamber Intraocular Lens Implantation during Diabetic Pars Plana Vitrectomy

Combined cataract removal, posterior chamber intraocular lens (PC IOL) implantation, and pars plana vitrectomy were performed in 15 diabetic patients who presented with coexisting cataract and vitreoretinal complications from proliferative diabetic retinopathy (PDR). Posterior chamber IOLs were placed anterior to the anterior lens capsule after pars plana lensectomy and vitrectomy in nine eyes, whereas extracapsular cataract extraction (ECCE) with PC IOL placement was performed before vitrectomy in six eyes. Panretinal laser endophotocoagulation was applied in 13 of the 15 eyes as an important part of the operative procedure. Because of. inactive diabetic retinopathy or satisfactory preoperative panretinal photocoagulation, 2 of the 15 eyes did not receive laser endophotocoagulation. Visual acuity was improved in 12 eyes and was similar to preoperative vision in 3 eyes. After a minimum of 6 months and a maximum of 28 months of follow-up, the visual results are the following: 20/40 or better (4 eyes), 20/50 to 20/200 (5 eyes), 20/400 to 5/200 (5 eyes), and hand motions (1 eye). Although 5 of the 15 eyes required secondary vitreoretinal procedures, neovascular glaucoma and complications attributable to the IOL did not occur. A recurrent postoperative retinal detachment (RD) developed with subsequent hypotony and rubeosis iridis in 1 of the 15 eyes.

A new phacoemulsification technique for in-the-bag IOL placement.

The standard phacoemulsification procedure includes capsulotomy with an irrigating cystotome and cortical cleanup with an irrigation/aspiration handpiece. While this is an effective technique, it produces ill-defined capsule edges that make in-the-bag placement of the implant difficult. We describe a technique that facilitates identification of capsular flaps by using scissors for the anterior capsulotomy, followed by cortical cleanup with the Gills technique and in-the-bag placement of the implant.

Intraocular Lenses and Experimental Bacterial Endophthalmitis

To determine if an intraocular lens renders bacterial endophthalmitis more resistant to therapy, an animal model was developed. Nine rabbits underwent bilateral extracapsular lens extraction with placement of a Simcoe posterior chamber IOL in one eye. Approximately 170 organisms of Staphylococcus aureus were inoculated into both eyes. The eyes of seen animals were treated with intravitreal and subconjunctival gentamicin after 24 and 48 hours. Vitreous cultures remained sterile in all treated eyes for one week after antibiotic therapy. Two animals that did not receive antibiotics showed persistent infection. There was no difference between aphakic and pseudophakic eyes in terms of clinical response or onset of negative cultures.

Infective Endocarditis: Diagnosis and Management

To determine if an intraocular lens renders bacterial endophthalmitis more resistant to therapy, an animal model was developed. Nine rabbits underwent bilateral extracapsular lens extraction with placement of a Simcoe posterior chamber IOL in one eye. Approximately 170 organisms of Staphylococcus aureus were inoculated into both eyes. The eyes of seven animals were treated with intravitreal and subconjunctival gentamicin after 24 and 48 hours. Vitreous cultures remained sterile in all treated eyes for one week after antibiotic therapy. Two animals that did not receive antibiotics showed persistent infection. There was no difference between aphakic and pseudophakic eyes in terms of clinical response or onset of negative cultures.