Arabinogalactan and hyaluronic acid in ophthalmic solution: Experimental effect on xanthine oxidoreductase complex as key player in ocular inflammation (in vitro study).

Dry eye syndrome is a common disease associated to eyes inflammation, irritation and tear film instability. The enzymatic complex of xanthine oxidoreductase (XOR) is involved in the generation of reactive oxygen species (ROS) and uric acid that, in the end, can cause reperfusion injuries, irritation and pathological conditions. Furthermore, in the eye, it has been proposed that oxygen free radicals might play a significant role in retinal ischemic damage. A new artificial drop formulation based on arabinogalactan and hyaluronic acid has been proposed in this article. The uric acid and the ROS formation have been monitored. The effect of the arabinogalactan, the hyaluronic acid and their mixture has been studied. The arabinogalactan entails a uric acid and ROS reduction of 27% and 38% respectively; no significant reduction of uric acid or ROS has been observed after the addition of hyaluronic acid alone. Notably the combination of arabinogalactan and hyaluronic acid involves the reduction of uric acid and ROS equal to 38% and 62%, namely. This study demonstrates that this artificial drop formulation can markedly reduce the uric acid and ROS formation in vitro; thus, the use of this formulation may contribute in the resolution of the dry eye syndrome.

Intraocular lens power calculation by ray-tracing after myopic excimer laser surgery.

PURPOSE: To investigate the refractive outcomes of intraocular lens (IOL) power calculation by ray-tracing after myopic excimer laser surgery. DESIGN: Prospective, interventional case series. METHODS: setting: Multicenter study. participants: Twenty-one eyes of 21 patients undergoing phacoemulsification and IOL implantation after myopic laser in situ keratomileusis or photorefractive keratectomy were enrolled. intervention: IOL power calculation was performed using internal software of a Scheimpflug camera combined with a Placido disc corneal topographer (Sirius; CSO). Exact ray-tracing was carried out after the axial length (measured either by immersion ultrasound biometry or partial coherence interferometry), target refraction, and pupil size had been entered. main outcome measures: Median absolute error, mean absolute error, and mean arithmetic error in refraction prediction, that is, the difference between the expected refraction (as calculated by the software) and the actual refraction 1 month after surgery. RESULTS: The mean postoperative refraction was -0.43 ± 1.08 diopters (D), with a range between -1.28 and 0.85 D. The mean arithmetic error was -0.13 ± 0.49 D. The median and mean absolute errors were +0.25 D and 0.36 D, respectively. Also, 71.4% of the eyes were within ± 0.50 D of the predicted refraction, 85.7% were within ± 1.00 D, and 100% within ± 1.50 D. CONCLUSIONS: Ray-tracing can calculate IOL power accurately in eyes with prior myopic laser in situ keratomileusis and photorefractive keratectomy, with no need for preoperative data.

Repeatability and agreement of 2 Scheimpflug analyzers in measuring the central corneal thickness and anterior chamber angle, volume, and depth.

PURPOSE: To evaluate the repeatability and agreement of 2 Scheimpflug tomographies (Pentacam HR, Oculus GmbH; Sirius, CSO Inc.) in measuring the central corneal thickness (CCT) and depth (ACD), volume (ACV), and angle (ACA) of the anterior chamber. METHODS: Three consecutive measurements were performed in one eye of each subject, with both instruments. The following were evaluated: CCT, ACD, ACV, and ACA. Repeatability was assessed by the Friedman test and agreement was assessed by 4 different Wilcoxon tests for paired data. RESULTS: The study enrolled 30 patients. With Sirius tomography the Friedman test p values for testing homogeneity across measurements was with respect to CCT 0.320, ACD 0.315, ACV 0.171, and ACA 0.020; and with Pentacam CCT 0.191, ACD 0.010, ACV 0.704, and ACA 0.150. The Wilcoxon test p values for testing the measurement homogeneity between the corneal tomography Sirius and Pentacam showed the following: ACD 0.000, ACD 0.000, ACV 0.853, and ACA 0.000. CONCLUSIONS: The measurements may be considered substantially stable for each corneal tomography and each variable, but the 2 corneal tomographies do not produce statistically equivalent measurements.

The use of the orbital septum in inferior palpebral reconstruction: the pocket technique.

BACKGROUND: Surgery involving massive inferior palpebral demolition often imposes the use of free flaps for the reconstruction of the anterior and posterior lamellae. PURPOSE: We describe a surgical technique which provides for the use of a homologous pedunculated elastic flap on which we wrap the free flap as in a pocket, in order to guarantee that the free flap itself takes root better. METHODS: A study of 10 patients admitted to our hospitals for massive inferior palpebral demolition surgery between March 2002 and November 2004 was undertaken, and clinical records (age, sex, involved site of lesions, surgery technique) were accurately noted: in all patients we performed the 'pocket technique'. RESULTS: The pocket technique has encouraged optimal attachment of the implanted free tissue, in absence of necrotic phenomena or tissue extrusion. CONCLUSIONS: Reconstructive surgery of the inferior eyelid avails itself of consolidated techniques. In case of extreme tissue reduction, the variation we wish to suggest is simple to understand and easy to perform, significantly reducing inflammatory reaction and/or post-surgical rejection, allowing excellent aesthetic results.

Stenosis of the lachrymal system in Rubinstein-Taybi syndrome.

In this article the authors describe a case of atypical stenosis of the lachrymal excretory system in Rubinstein-Taybi syndrome (RTS) characterised by morphologic anomalies of the lachrymal bag and by alterations of the osseous structure of the nose. A 9-year-old girl, with typical findings of RTS, was affected by recurrent acute dacryocystitis and tearing. Ocular examination revealed bilateral reflux with mucous and purulent material flowing back after digital pressing: low and bilateral nose-lachrymal duct obstruction was the main cause of the reflux as confirmed by orifice probing, lachrymal drainage system irrigation and spiral CT examination using hydrosoluble contrast medium. The multiplanar reconstruction obtained from CT scanning shows that the right lachrymal sac has an abnormal shape ('grape-bunch' image) and that the left one has various bulgings, or swellings, in its shape. The 'grape-bunch' lachrymal bags are the most unusual features of our patient's lachrymal system and it is important to consider the difficulties that could occur during surgery because of the abnormal bag shape and because of the increased bone thickness in RTS patients. The 'grape-bunch' lachrymal sac is a truly unusual anatomical feature and, most probably, it could be distinctive of this syndrome.