Comparison of postoperative refractive outcome in eyes undergoing combined phacovitrectomy vs cataract surgery following vitrectomy

Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate the accuracy of preoperative biometry in eyes undergoing combined phacovitrectomy and to compare it with eyes...     

Retinal complications of phakic intraocular lenses

High myopia has always been a challenge for refractive correction. Current laser surgical techniques, however, fall short of correcting high refractive errors due to lack of predictability, regression, corneal ectasia, and introduction of high order optical aberration. Phakic intraocular lenses (IOL) have been proposed as an effective refractive surgical procedure for the correction of severe myopia, but, despite recent advances in implant material technology and design, their concept is still under clinical investigation. Most of the concern regarding the complications of phakic IOLs focuses on the anterior segment of the eye. This review examines the posterior segment complications associated with phakic IOL implantation, evaluates possible pathogenetic mechanisms and discusses posterior segment complications, prevention and management.     

Retinal complications of phakic intraocular lenses

High myopia has always been a challenge for refractive correction. Current laser surgical techniques, however, fall short of correcting high refractive errors due to lack of predictability, regression, corneal ectasia, and introduction of high order optical aberration. Phakic intraocular lenses (IOL) have been proposed as an effective refractive surgical procedure for the correction of severe myopia, but, despite recent advances in implant material teachnology and design, their concept is still under clinical investigation. Most of the concern regarding the complications of phakic IOLs focuses on the anterior segment of the eye. This review examines the posterior segment complications associated with phakic IOL implantation, evaluates possible pathogenetic mechanisms and discusses posterior segment complications, prevention and management.     

Non-contact holmium:YAG laser thermal keratoplasty for hyperopia: two-year follow-up

PURPOSE: We evaluated the safety and efficacy of the non-contact holmium:YAG laser thermal keratoplasty (LTK) for the treatment of mild to moderate hyperopia without astigmatism. METHODS: A prospective, non-comparative case series included 50 eyes of 28 patients (aged > or =40 years) who had stable refraction and an astigmatic component < +0.50 diopters (D). We applied the non-contact pulsed holmium:YAG laser to treat the hyperopic spherical component using the Hyperion LTK System. All patients had minimum 12-month follow-up and 64% (18 patients) had 24-month follow-up. RESULTS: The mean age of patients was 48.4 +/- 8.23 years (range: 40 to 62 years). The preoperative hyperopic mean spherical equivalent refraction was +2.32 +/- 0.975 D (range: +1.00 to +4.75 D). Postoperatively, the subjective manifest refraction decreased from the preoperative mean value of +2.32 D to a mean -0.09 D at 1 month after surgery and regressed to +0.315 D at the last follow-up examination, resulting in a mean correction of +2.005 +/- 0.81 D at 24 months after surgery. Preoperatively, mean uncorrected visual acuity in LogMAR units was 0.798 +/- 0.353 and at 12 months after surgery, it was a mean 0.108 +/- 0.136. Keratometric power increased from 42.595 +/- 1.949 D before surgery to 44.605 +/- 1.626 D at 24 months after surgery. CONCLUSIONS: Holmium:YAG LTK was an acceptable alternative for the correction of mild to moderate hyperopia in this middle-aged population.     

Iris configuration in accommodation in pigment dispersion syndrome

PURPOSE: This study was conducted in order to investigate the effect of accommodation on the iris morphology and iridolenticular contact, in eyes with Pigment Dispersion Syndrome and Pigmentary Glaucoma, using high-resolution ultrasound. METHODS: We performed a prospective observational study, examining a group of 30 Pigment Dispersion Syndrome and Pigmentary Glaucoma patients (49 eyes) and a smaller group of eight 'normals' non-Pigment Dispersion Syndrome patients (8 eyes). All patients underwent ultrasound biomicroscopy, before and during accommodation. RESULTS: The iris profile before accommodation was found convex in 48.5%, flat in 19.7% and concave in 31.8%. Following accommodation the iris configuration remained unchanged in 66.2%, increased in concavity in 20.3% and decreased in concavity in 13.5%. CONCLUSIONS: The effect of accommodation on iris configuration and accommodation is highly variable. From our experience the measurement of iris configuration using ultrasound biomicroscopy may not be a useful method of evaluating the effect of different treatments on iris configuration.     

Intraobserver and interobserver reliability of the R/D score for evaluation of iris configuration by ultrasound biomicroscopy,in patients with pigment dispersion syndrome

The work has been presented at The Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting, Fort Lauterdale, Florida, May 1999. PURPOSE: To evaluate inter- and intraobserver variability of the R/D score in assessing the iris configuration in Pigment Dispersion Syndrome patients. METHODS: Fifty-seven high-resolution ultrasound biomicroscopy images were obtained by a single ophthalmologist. All images were examined twice by each of three ophthalmologists, the second assessment being at least 2 weeks after the first. Each observer was masked to their colleagues' and their previous measurements. R/D scores were calculated at each examination. Agreement between and amongst observers was assessed using Bland-Altman plots. In addition, the R/D scores were categorised and reassessed using the Kappa statistic. RESULTS: Intraobserver variability was small, the average differences between first and second scores of each observer being less than 0.01 units. Agreement within observers was 89% or higher, with Kappa values of 0.8 or higher, indicating almost perfect agreement. Interobserver variability was, however, greater. Although there was substantial agreement between two of the observers (87% agreement, first assessment; 80%, second assessment with respective kappa statistics of 0.78 and 0.66), they only moderately agreed with the other observer (kappa statistics between 0.55 and 0.68). CONCLUSIONS: This study suggests that when using R/D scores to demonstrate changes in iris configuration, assessments should preferably be made by the same observer.     

Functional and anatomic results of macular hole surgery complicated by massive indocyanine green subretinal migration

PURPOSE: To report the functional and anatomic results of macular hole (MH) surgery complicated by massive subretinal migration of indocyanine green (ICG) dye. DESIGN: Interventional case report. METHODS: We performed standard pars plana vitrectomy surgery for a stage 3, senile idiopathic MH. After posterior vitreous detachment and vitreous removal, we instilled 2 ml of ICG (0.5%, 270 mOsm); the surgery was complicated by diffuse subretinal migration of the ICG dye but peeling of the internal limiting membrane (ILM) was performed (despite the obvious difficulties from the low contrast between the green-stained ILM overlying a green-stained subretinal space) and the rest of the procedure was completed with a final injection of 16% C3F8. RESULTS: Post-surgical optical coherence tomography confirmed the anatomic closure of the MH. Digital photography with the excitation and barrier filters for ICG showed a striking autofluorescence along the inferior vascular arcade, which remained intense 7 months after surgery. Despite the massive subretinal migration of ICG, visual acuity (VA) improved to 20/30. CONCLUSIONS: This is the first report of VA recovery despite massive subretinal migration of ICG dye during MH surgery. Subretinal migration of ICG dye may be a potential complication during MH surgery; this should alert the surgeon to limit its use, despite the possible absence of clinically apparent toxic effects.     

Sulcus implantation of a 3-piece, 6.0 mm optic,hydrophobic foldable acrylic intraocular lens in phacoemulsification complicated by posterior capsule rupture

To evaluate the safety of implanting a 3-piece, 6.0 mm optic, foldable acrylic intraocular lens (IOL) in cases of posterior capsule rupture during phacoemulsification.Department of Ophthalmology, Ahepa Hospital, Aristotle University Medical School, and Interbalkan Medical Center, Thessaloniki, Greece.This prospective noncomparative case series included 28 eyes (28 patients) having phacoemulsification complicated by extensive posterior capsule rupture with or without vitreous loss. In all eyes, a 3-piece, 6.0 mm optic, foldable acrylic IOL (AcrySof MA60BM, Alcon) was implanted in the sulcus. Postoperative examination included best corrected visual acuity (BCVA), anterior segment biomicroscopy, IOL centralization and position, intraocular pressure (IOP), and fundus biomicroscopy. The follow-up was 6 months.The most common postoperative complications were transient corneal edema in 12 eyes and increased IOP in 11 eyes. Slight asymptomatic decentralization from the center of the pupil (1.0 to 2.0 mm) and pseudophacodonesis were observed in 5 eyes each. Friction of the IOL with the iris occurred in 1 eye. Clinically significant cystoid macular edema occurred in 3 eyes. The final BCVA was between 20/15 and 20/25 in 18 patients, 20/30 in 2, between 20/40 and 20/50 in 4, and between 20/60 and 20/200 in 4.AcrySof IOL implantation in the sulcus during phacoemulsification complicated by posterior capsule rupture preserved the advantages of small-incision surgery. The postoperative behavior and centralization of the IOLs resembled those of poly(methyl methacrylate) lenses.