Evaluation of a Novel Blue-Colored Ophthalmic Viscoelastic Device Applied during Phacoemulsification in Eyes with Pseudoexfoliation Syndrome

Recently, a new development in the field of ophthalmic viscoelastic devices (OVDs) has been introduced. The blue-colored OVD Pe-Ha-Blue® PLUS combines the viscoelastic properties of OVD together with trypan blue for better visualization during surgery. The objective of this case series is to investigate whether the use of a blue-colored OVD during cataract surgery in patients with pseudoexfoliation syndrome (PXF) and narrow pupils (miosis) has advantages over the use of a clear standard OVD in combination with trypan blue. We included 52 eyes of 52 consecutive cataract patients diagnosed with PXF. Study participants were divided into two groups of 26 patients each, depending on which OVD was used during surgery (group A: blue-colored OVD; group B: standard clear OVD). Intraoperatively, we evaluated the operation time (surgery start to the beginning of phacoemulsification) and the surgeon’s satisfaction with the surgical workflow. Postoperative examinations were performed 6 h, 20 h, and 4 weeks after surgery and included corrected distance visual acuity (CDVA) and intraocular pressure (IOP). Our results show that there was a statistically significant time gain in group A in terms of surgery time. In addition, findings on surgeon satisfaction, postoperative CDVA and IOP suggest further benefits in group A. We discuss further properties and possible advantages which may result from the use of a blue-colored OVD. In summary, a blue-colored viscoelastic device can be a helpful alternative to clear OVD especially in challenging cases to improve the surgical workflow and make the whole procedure even safer and faster

Comparison of Wash-out Properties after Use of the Vital Dye Trypan Blue in the Form of an Ophthalmic Dye and Bound in a Sodium Hyaluronate by Raman Spectroscopy

In cataract surgery, the creation of the anterior capsulorhexis as one of the critical steps is of most importance for the surgical success. In challenging initial situations (e.g. in eyes with pseudoexfoliation syndrome, mature, brunescent cataract, juvenile cataract, corneal opacities, or in post-traumatic and postuveitic cases), vital dyes are used as a routine to increase the visibility and plasticity of the ocular structures in the anterior chamber. The range of applications of the vital dye trypan blue (TB) has expanded considerably in recent years due to its excellent staining properties.1 However, its use in ophthalmology as an effective and useful tool requires that the dye has no adverse effects on the cell structures of the eye. As two laboratory studies on cell cultures showed, the time of exposure to TB plays an important role in addition to concentration.2,3 The in vitro studies by Chang et al. with rabbit corneal endothelial cell cultures, and van Dooren et al.3 demonstrated no toxicity of TB with a maximum concentration of 0.4% after 1 minute in cell cultures of human corneal fibroplasts. A significant toxicity of a TB concentration of 0.01% or higher after exposure was observed. At 24-hour exposure, a TB concentration of 0.005% was found to be the threshold for a significant cytotoxicity index. In principle, it is important to note that trypan blue can be cytotoxic at a certain concentration. Monoazo, the most toxic of known impurities found in trypan blue dyes can be carcinogenic. However, the TB concentrations used in eye surgery do not have undesirable effects on the cell structures of the eye and are therefore generally considered safe.3,4 However, a case report showed a transient retinal toxic reaction in the form of transient visual field defect following the entry of TB into the vitreous body space.5 In modern intraocular procedures viscoelastic substances (OVDs, ophthalmic viscoelastic devices) are widely used. Since their introduction in the 1970s, they have been routinely used in cataract surgery and serve to protect sensitive eye structures from mechanical injuries or to create and maintain anatomical spaces such as the anterior chamber or the capsular bag. They increase safety during the procedure and can also shorten overall surgery time by improving visibility and simplifying some surgical steps for the surgeon.6 A shorter surgery time is associated with a lower degree of trauma and a lower risk of complications, and may ultimately be associated with faster recovery and a better final outcome and satisfaction for the patient. In addition, from an economic point of view, the time saving factor is particularly important for high-volume facilities. After the introduction of Healon® in 1979, sodium hyaluronate became the most widely used biopolymer for OVDs in intraocular surgery. Since then, the pharmacological, physiological, and clinical aspects of sodium hyaluronate for ophthalmic applications have been assessed in a large number of studies.7,8 Recently, a combination of a viscoelastic with the vital dye TB has been introduced (Pe-Ha-Blue®PLUS, Albomed, Schwarzenbruck, Germany) and has already been clinically investigated in a prospective case series of 52 eyes with pseudoexfoliation syndrome.6 In addition to a significantly shorter surgery time (due to fewer individual surgical steps) with cost- and safety-relevant advantages of Pe-Ha-Blue®PLUS compared to separate administration of OVD (POLY-HYL® 1. 6%; Polytech Domilens GmbH) and TB (Vision Blue®; DORC, Holland/Blue Color Caps®), the surgeon gains better control over whether the OVD is removed completely at the end of surgery by using the blue OVD. This should also reduce postoperative complications such as hypertension due to OVD residues remaining in the eye. The aim of the present in vitro study was to determine by Raman spectroscopy the amount of residue of the TB dye that remains on a slide during the routine application of two commercial products (TB dye Vision Blue® and Pe-Ha-Blue®PLUS). In Raman spectroscopy, the interaction of light and matter is used to investigate, for example, the properties of a material or to enable the microscopic examination of materials. Excited by monochromatic light, the sample emits scattered light with a specific frequency shift. The frequency shift (the so-called Raman shift) contain information about the vibrational states of the molecules and thus about the chemical composition and structure of the sample. This phenomenon was discovered by Sir C. V. Raman in the early 20th century. Since the beginning of the 20th century, the method, today mostly stimulated by a laser light source, is widely used in fields such as industry, chemistry, archaeology or for the qualitative and quantitative analysis of products in the pharmaceutical industry

Correlación clínico-patológica de las microvacuolas o ‘glistenings’ en 100 lentes intraoculares (lios) AcrySof® explantados

Propósito:analizar los LIOs acrílicos hidrofóbicos AcrySof® de nuestro banco de lentes explantados para establecer la presencia de microvacuolas (glistenings), determinar su frecuencia y definir si existe una correlación con los datos clínicos para cada uno.Materiales y Métodos: se realizó análisis clínico-patológico de todos los lentes hidrofóbicos AcrySof® (n=100) que hacen parte del banco de más de 5.000 explantes de nuestro laboratorio. Se efectuó evaluación microscópica y se determinó la presencia de las microvacuolas; adicionalmente se estimó la severidad de las mismas y se hizo una correlación con los datos clínicos para cada lente.Resultados:el análisis foto microscópico reveló la presencia de microvacuolas en 43 de los 100 LIOs evaluados. Las microvacuolas fueron clasificadas como eves en 14 casos, moderadas en 17 y marcadas en 12. Del total de lentes con microvacuolas solamente en 6 casos se hizo el diagnóstico clínico de las mismas.Conclusiones: estas observaciones nos permiten concluir que a menudo se pasa por alto el diagnóstico de esta entidad. Esta entidad es más común de lo que muchos estiman. No existen en la actualidad criterios uniformes sobre el tiempo de seguimiento posoperatorio; de ahí la razón por la que no se diagnostican correctamente las microvacuolas y la controversia entre los cirujanos y los investigadores persist

Patient and Surgeon Satisfaction Levels after Using an Acrylic, Hydrophobic, Monofocal IOL and the Malyugin Ring in Pseudoexfoliation Syndrome Patients

Purpose. The purpose of this prospective analysis was to evaluate the patient and surgeon satisfaction levels after using a fully preloaded acrylic, hydrophobic, monofocal “premium” IOL in pseudoexfoliation syndrome. Materials and Methods. 42 eyes of twenty-eight patients with progressed cataract formation and pseudoexfoliation syndrome (PXF) or pseudoexfoliation glaucoma and best corrected distance visual acuity (BCDVA) between 0.30–1.00 logMAR were enrolled. After a detailed preexamination, they underwent phacoemulsification and implantation of the acrylic, hydrophobic, heparin-coated, single-piece, monofocal intraocular lens (CT LUCIA 601P, Zeiss, Germany) with 360° square edge and ultraclear purity aspheric ZO optic. We evaluated the visual performance of the IOL and the patient satisfaction. We also evaluated the intraoperative handling of the injector and the behavior of the IOL in these complicated cases (PXF). Results. The BCDVA increased from mean 0.48 logMAR (range 0.30–1.00 logMAR) preoperatively to −0.05 ± 0.13 logMAR postoperatively. The mean IOL power was 23.5 D (range 16.5–27.5 D). The target refraction using the Haigis formula within ±0.5 D was reached by 92.9% (n=39) and by 100% (n=42) within 1.0 D of all cases, respectively. Patient satisfaction was very high, and no halos or glare were reported in any case. The fully preloaded injector system enabled an easy IOL preparation and safe implantation. Conclusion. Our results show that the implantation of the fully preloaded CT LUCIA 601P (Zeiss, Germany) is safe and enhances OR workflow in complicated cases as pseudoexfoliation. In these cases, an adapted approach (special preoperative, intraoperative, and postoperative regime) with considering possible complications is necessary to achieve best outcomes

Nano-Indentation to Determine Mechanical Properties of Intraocular Lenses: Evaluating Penetration Depth, Material Stiffness, and Elastic Moduli

Abstract Introduction Intraocular lenses (IOL) should remain in the eye for life after implantation into the capsular bag during cataract surgery. The material must meet various requirements. It is crucial that the material has the best biocompatibility, and it should be flexible and soft for best possible implantation process but also sufficiently stable and stiff for good centering in the eye and posterior capsule opacification prevention. Methods In this laboratory experiment, we used nano-indentation for the mechanical assessment of three hydrophobic acrylic (A, B, C), three hydrophilic acrylic (D, E, F), and one silicone (G) intraocular lens. We wanted to determine whether some react more sensitively to touching/handling than others. The indentation elastic modulus and the creep were obtained from the force displacement curve. For measuring penetration depth and testing of possible damage to the intraocular lenses, the samples were measured at room temperature. A 200-µm-diameter ruby spherical tipped indenter was used for all the tests. Indentations were made to three different maximum loads, namely 5 mN (milli Newton), 15 mN, and 30 mN and repeated three times. Results The lowest penetration depth (12 µm) was observed with IOL B. However, IOL A, D, and F showed similar low penetration depths (20, 18, and 23 µm, respectively). Lenses C and E showed slightly higher penetration depths of 36 and 39 µm, respectively. The silicone lens (G) showed the greatest penetration depth of 54.6 µm at a maximum load of 5 mN. With higher maximal loads (15 and 30 mN) the penetration depth increased significantly. Lens C, however, showed the same results at both 15 and 30 mN with no increase of penetration depth. This seems to fit well with the material and manufacturing process of the lens (lathe-cut). During the holding time of 30 s at constant force all six acrylic lenses showed a significant increase of the creep (C IT 21–43%). Lens G showed the smallest creep with 14%. The mean indentation modulus (E IT) values ranged from 1 to 37 MPa. IOL B had the largest E IT of 37 MPa, which could be caused by the low water content. Conclusion It was found that results correlate very well with the water content of the material in the first place. The manufacturing process (molded versus lathe-cut) seems to play another important role. Since all included acrylic lenses are very similar, it was not surprising that the measured differences are marginal. Even though hydrophobic materials with lower water content showed higher relative stiffness, penetration and defects can also occur with these. The surgeon and scrub nurse should always be aware that macroscopic changes are difficult to detect but that defects could theoretically lead to clinical effects. The principle of not touching the center of the IOL optic at any time should be taken seriously

Video analysis of optic-haptic-interaction during hydrophobic acrylic intraocular lens implantation using preloaded injectors

Abstract Objective To compare the optic-haptic interaction of different hydrophobic acrylic IOLs after using six preloaded injectors. Methods We reviewed the video-recordings of procedures on a total of 388 eyes that underwent phacoemulsification and intraocular lens (IOL) implantation. For six preloaded injectors: multiSert (Hoya Surgical Optics) [System 1], TECNIS Simplicity (Johnson & Johnson Vision) [System 2], TECNIS iTec (Johnson & Johnson Vision) [System 3], AutonoMe (Alcon, Laboratories) [System 4], Bluesert (Carl Zeiss Meditec) [System 5], and Prosert (OphthalmoPro GmbH) [System 6], we noted in each case the time of IOL delivery and made a descriptive observation of IOL insertion and optic-haptic-interaction. Results We defined standard haptic behavior where the haptics emerged “folded” from the injector and quickly recovered their pre-implantation appearance. The incidence where the leading haptic emerged in a deformed way for System 1 was 20%, System 2: 19%, System 3: 14%, System 4: 56%, System 5: 24% and System 6: 5%. For trailing haptic deformed behavior, the incidence was 36%, 6%, 4%, 8%, 18% and 2%, respectively for Systems 1 to 6. Optic-haptic adhesion occurred in 2% of cases for System 1, 44% for System 2, 52% for System 3, 48% for System 4, and 11% for System 6 (P < 0.05). Adhesion was not found with System 5. Conclusions We observed different deformed behavior for leading and trailing haptics in the six preloaded systems, some systems had as much as 52% optic-haptic adhesion