ABSTRACT
Hemoderivative tear substitutes contain various ephiteliotrophic factors, such as growth factors (GF), involved in ocular surface homeostasis without immunogenic properties. The aim of the present work was the loading of platelet lysate into contact lenses to improve the precorneal permanence of platelet lysate growth factors on the ocular surface to enhance the treatment of corneal lesions. To this purpose, chondroitin sulfate, a sulfated glycosaminoglycan, which is normally present in the extracellular matrix, was associated with platelet lysate. In fact, chondroitin sulfate is capable of electrostatic interaction with positively charged growth factors, in particular, with bFGF, IGF, VEGF, PDGF and TGF-ß, resulting in their stabilization and reduced degradation in solution. In the present work, various types of commercially available contact lenses have been loaded with chondroitin sulfate or chondroitin sulfate in association with platelet lysate to achieve a release of growth factors directly onto the corneal surface lesions. One type of contact lenses (PureVision(®)) showed in vitro good proliferation properties towards corneal cells and were able to enhance cut closure in cornea constructs.
Subject(s)
Blood Platelets/metabolism , Chondroitin Sulfates/administration & dosage , Cornea/drug effects , Corneal Diseases/drug therapy , Intercellular Signaling Peptides and Proteins/administration & dosage , Animals , Cell Proliferation/drug effects , Cells, Cultured , Contact Lenses , Extracellular Matrix/metabolism , Human Umbilical Vein Endothelial Cells , Humans , Rabbits , Wound Healing/drug effectsABSTRACT
PURPOSE: To assess the sensitivity and specificity of Pentacam measurements in detection of occludable angles and to provide cutoff values. METHODS: Observational, single-center, cross-sectional study on 64 Caucasian eyes: 28 (43.7%) primary narrow angles or primary angle-closure glaucoma, and 36 (56.2%) controls: all subjects were evaluated and classified by gonioscopy (Shaffer classification). The following measurements have been considered: superior and inferior anterior chamber angle (ACA), temporal and nasal ACA, anterior chamber depth (ACD) using 5 value representation (central, superior, inferior, nasal, temporal), and anterior chamber volume (ACV). Validity of Pentacam parameters to detect patients in Shaffer 0 or I class was assessed by receiver operating characteristic (ROC) curves analysis; cutoffs were chosen as to maximize sensitivity and specificity. RESULTS: All the considered Pentacam measures were statistically different between the 2 groups (p<0.0001). All Shaffer grade groups differed in all parameters (p<0.001), except for grade 0 and I, which did not differ in any. Area under the curve ROC analysis revealed high discriminant power of all Pentacam measures: ACA = 0.94; ACD = 0.91; ACD central = 0.89; and ACV = 0.89. Chosen cutoff values (ACA = 22.4°; ACD = 1.12 mm; ACD central = 1.93 mm; ACV = 84 mm3) allowed correct classification of narrow angles. CONCLUSIONS: The study pointed out a high power of Pentacam AVA, ACV, and ACD in detecting occludable angles. Pentacam is simple to use, reliable, and noncontact, provides parameters in a short period, and represents a possible screening tool.
Subject(s)
Anterior Chamber/pathology , Diagnostic Techniques, Ophthalmological/instrumentation , Glaucoma, Angle-Closure/diagnosis , Photography/instrumentation , Aged , Cross-Sectional Studies , Female , Gonioscopy , Humans , Intraocular Pressure , Male , ROC Curve , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
PURPOSE: Laser iridotomy is the standard first-line intervention in both acute and chronic forms of angle closure because it prevents the recurrence of acute attacks and virtually eliminates the risk of an acute attack in the fellow eye. Pentacam is a new imaging modality which does not require probe contact or an immersion bath. The instrument will allow anterior segment morphology before and after laser peripheral iridotomy (LPI) to be quantified. The aim of the study is to evaluate the objective difference in changes of anterior chamber morphology after LPI with Pentacam. METHODS: Twenty eyes with a high risk of angle closure were evaluated with Pentacam rotating Scheimpflug camera before and after LPI. We measured anterior chamber volume, anterior chamber depth, and chamber angle before and after laser treatment. RESULTS: Statistically significant difference before and after LPI was noted in all anterior chamber measurements except central anterior chamber depth. CONCLUSIONS: This study confirms previous reports of increased anterior chamber volume and angle after LPI and Pentacam is a good objective instrument to demonstrate the efficacy of LPI.