Propionibacterium acnes in capsular bag distension syndrome.

We report a case of capsular bag distension syndrome that developed 6 years after uneventful phacoemulsification with implantation of a foldable, single-piece acrylic intraocular lens (IOL) (AcrySof MA60BM). Slitlamp microscopy revealed a deep anterior chamber with no flare or cells. The posterior capsular bag was distended by a homogeneous milky substance between the back of the IOL and the capsular bag. Using a pars plana approach, a 23-gauge bimanual capsulotomy and anterior vitrectomy were performed. Microbiological analysis revealed Propionibacterium acnes in the material inside the capsular bag. The postoperative period was uneventful. Four weeks after surgery, visual acuity was restored and there were no signs of intraocular inflammation. The origin of late capsular bag distension is not fully understood; it may involve an infectious component with propionibacteria. A surgical approach and removal of the potentially infectious material can be considered as an alternative to neodymium:YAG capsulotomy.

Diabetic retinopathy: Early diagnosis and effective treatment.

BACKGROUND: Diabetic retinopathy is a microangiopathy of the retina from which nearly all persons with diabetes eventually suffer. Two of its complications threaten the patient's vision: diabetic macular edema and proliferative diabetic retinopathy. METHODS: Selective literature review, based on national and international guidelines and a literature search from 1981 onward. RESULTS: Diabetic retinopathy is subdivided into non-proliferative and proliferative retinopathy. Macular edema can arise at any stage of the disease and threatens visual acuity. The main risk factors for the development and progression of diabetic retinopathy are long duration of diabetes and poor control of blood sugar and arterial blood pressure. Laser photocoagulation is an evidence-based treatment for proliferative retinopathy and macular edema. Vitreous surgery is indicated in cases of worsening vision due to a non-clearing vitreous hemorrhage or tractional retinal detachment. The current options for medical treatment involve the intravitreous injection of glucocorticosteroids or of a VEGF antagonist; both of these options are "off label" at present. CONCLUSION: Diabetic retinopathy is the leading cause of blindness among persons of working age in the industrialized world. Regular ophthalmological examinations, timely laser therapy depending on the stage of the disease, and close interdisciplinary cooperation are essential to prevent loss of vision.

Amadeus II microkeratome: optimizing microkeratome settings for high flap accuracy using optical low coherence reflectometry.

PURPOSE: To investigate the impact of various experimental microkeratome settings and blade reuse on the accuracy of the flap thickness created with the new Amadeus II microkeratome (SIS, Ziemer Ophthalmic, Port, Switzerland). METHODS: In this prospective study, 120 porcine eyes were used to create corneal flaps with the Amadeus II using 2 different cutting heads (140 microm, 160 microm) with the Surepass blade. Using each blade twice, a head advance speed of 1.5 mm/s and 3.5 mm/s and oscillation rates of 8000 rpm, 10,000 rpm, and 13,000 rpm were used. Flap thickness was measured by optical low coherence reflectometry (OLCR). Descriptive statistical analysis was based on means, medians, and quartiles, with graphical representation on box plot. Pearson correlation test and Mann-Whitney U-test for unpaired samples were employed to identify the impact of different settings. RESULTS: Using the 140 microm cutting head, highest precision of the flap thickness was achieved with a head advance rate of 1.5 mm/s and an oscillation rate of 10,000 rpm (mean 132.1+/-10.0 microm; range 120.2-147.2 microm). Reusing the blade, highest accuracy (mean 130+/-6.9 microm; range 118.5-135 microm) was achieved with 8000 rpm. Using the 160 microm cutting head, an optimum flap thickness was reached with a head advance rate of 3.5 mm/s and an oscillation rate of 13,000 rpm (mean 162.4+/-7.7 microm; range 151.9-169.8 microm). Reusing the blade with the 160 microm cutting head, an adjustment to 3.5 mm/s and 10,000 rpm was necessary (mean 157.4+/-7.7 microm; range 153.7-161.8 microm). CONCLUSIONS: Optimized microkeratome settings lead to minimized deviation from the intended flap thickness and are mandatory to improve flap accuracy. OLCR is an ideal method to proof individualized settings.

Two-step LASIK after penetrating keratoplasty.

PURPOSE: The point of interest of this retrospective case review is to study refractive changes caused by the hinged lamellar keratotomy and the refractive outcome after laser ablation in a second step within the scope of laser in situ keratomileusis (LASIK) in patients with penetrating keratoplasty. METHODS: Data from eight patients obtained before lamellar keratotomy, before laser ablation, and three months later were evaluated. Keratotomies were performed with the Moria((R)) LSK one and the Amadeus((R)) 2 microkeratome, laser ablation was performed with the Schwind((R)) Keratome I and the Wavelight((R)) Allegretto WaveEyeQ. RESULTS: Uncorrected visual acuity (UCVA) improved significantly from 1 [logMar] to 0.4 [logMar] at the last visit. Median gain of UCVA was 7.38 +/- 2.96 Snellen lines. Best spectacle-corrected visual acuity did not change significantly. Preoperative manifest refraction spherical equivalent decreased from -4.02 +/- 4.77 diopters (D) to -1.11 +/- 2.45 D after laser ablation. Mean preoperative manifest astigmatism was -7.27 +/- 3.65 D, after lamellar keratotomy -6.72 +/- 3.68 D, and after laser ablation -2.08 +/- 1.80 D. Manifest astigmatism did not change significantly after the keratotomy. CONCLUSIONS: Lamellar keratotomy causes biomechanical changes to the cornea. We favor a two-step LASIK in penetrating keratoplasty patients in order to improve precision and predictability of the refractive outcome.

Customizing the Amadeus II microkeratome: evaluation of cut quality with various settings using electron microscopy.

PURPOSE: To evaluate the cut quality of keratectomy specimens created with the new Amadeus II microkeratome (SIS, Ziemer Ophthalmic, Port, Switzerland) using scanning electron microscopy (SEM). Methods. Corneal cuts were performed in 24 freshly enucleated porcine eyes using the Amadeus II microkeratome with combinations of cutting-head depth, oscillation rate, head-advance speed, and reuse of the blade. For the cutting trials, a 140-microm and 160-microm cutting head with three oscillation rates of 8,000, 10,000, and 13,000 rpm and two head-advance speed rates of 1.5 and 3.5 mm/s were chosen. In each setting, the blade was reused for a second time. All eyes were included, resulting in 4 groups with 6 eyes for each configuration. The surface and edge of the corneal cut was examined using SEM. RESULTS: At fixed oscillation rates, an increase in head-advance speed led to lower quality cuts, higher surface roughness, and irregular cut edges for both cutting heads (140 microm/160 microm), especially when using the blade for a second time. At fixed head-advance speeds an increase in oscillation rates improved the cut quality for both cutting heads (140 microm/160 microm). This results in smoother surface characteristics and more regular cut edges, especially when using the blade for the first time. CONCLUSIONS: Using the Amadeus II microkeratome for laser in situ keratomileusis procedures, the optimum oscillation rate, the optimum head-advance speed, and a single use of the blade will produce a very smooth and regular surface and cut edge for safe, comfortable, and improved customized refractive surgery.

Epi-LASIK using the Amadeus II microkeratome: evaluation of cut quality using light and electron microscopy.

PURPOSE: To investigate the cut quality and surface characteristics of the epithelial flap and underlying Bowman's membrane created by the Amadeus II (AMO) microkeratome on human corneas using light and electron microscopy. SETTING: Center for Refractive Therapy, Department of Ophthalmology, Ludwig-Maximilians University, Munich, Germany. METHODS: Using a 9.0 mm type II suction ring and settings, as recommended by the manufacturer, epithelial laser in situ keratomileusis (epi-LASIK) was performed in 2 fresh human eyes of 1 donor. Ocular pathology and previous ocular surgery were ruled out. Tissues for light microscopy were examined using hematoxylin-eosin and periodic acid-Schiff reaction staining. Further tissue samples were examined using scanning electron microscopy and transmission electron microscopy. RESULTS: Light microscopy showed a thoroughly separated epithelial sheet with no evident anatomical abnormalities. Stratification of the separated epithelium layer and cell shape was conserved. The cleavage plane was located at Bowman's membrane. Scanning electron microscopy showed a consistent transition from adherent epithelium to the denuded area. Bowman's layer showed a very smooth surface without remains of basal lamina. Transmission electron microscopy examination showed interruptions of the basement membrane at high magnification. CONCLUSIONS: This in vitro study found a high cut quality using the epi-LASIK separator of the Amadeus II microkeratome. The resulting cleavage plane at Bowman's membrane was well suited for the subsequent laser ablation.

Phototherapeutic keratectomy in children.

PURPOSE: Children with dense superficial opacities of the cornea are at risk for developing amblyopia. This study evaluated the efficacy of phototherapeutic keratectomy (PTK) in severe cases of anterior stromal scarring. METHODS: Five eyes of five patients, aged 6 to 8 years, were included. Three children suffered from uveitis-associated band keratopathy, one child had anterior corneal stromal scarring due to viral infection, and one child had anterior basement membrane dystrophy. Phototherapeutic keratectomy was performed under general anesthesia using the 200 Hz ALLEGRETTO excimer laser. Optical treatment zone was 7.0 mm (one eye) and 8.0 mm (four eyes), and ablation depths were between 20 and 100 microm. Postoperative treatment consisted of bandage soft contact lens, topical preservative-free antibiotics, steroids, and artificial tears. Part-time occlusion therapy was continued, as prior to PTK. Because of the small cohort, statistical evaluation was not performed. RESULTS: Mean follow-up was 23.4 +/- 13.7 months (range: 10 to 41 months). Surgery and postoperative follow-up were uneventful, and no signs of infection or haze were noted. Preoperative best spectacle-corrected visual acuity was 0.4 to 3.0 logMAR (mean: 1.22 +/- 1.07 logMAR). Best spectacle-corrected visual acuity improved in four eyes and stabilized in one eye due to uveitis recurrence (mean 0.64 +/- 0.65 logMAR). Mean preoperative keratometric values changed from 45.60 +/- 0.90 to 44.90 +/- 3.00 diopters postoperatively. CONCLUSIONS: Dense superficial corneal opacity in children may be successfully treated with PTK. Phototherapeutic keratectomy was performed to increase corneal transparency and corneal surface smoothing thereby avoiding amblyopia.