Results of a modified non-penetrating deep sclerectomy in the treatment of open angle glaucoma with or without cataract

PURPOSE: To present the technique of a modified deep sclerectomy, which we will call "reversed" deep sclerectomy (RDS) and the results and our observations of its use in patients with open angle glaucoma (OAG) and with or without cataract extraction (phacoemulsification). MATERIALS AND METHODS: This prospective study included 132 eyes which underwent RDS: 37 eyes (group A) with uncontrolled OAG and 95 eyes (group B) with OAG and visually significant cataract. Mean pressure preoperatively for group A was 24.48 +/- 4.92 mmHg and for group B was 22.99 +/- 3.00. The mean number of antiglaucoma drugs received was 2.97 +/- 0.69 and 2.56 +/- 0.73 for groups A and B respectively. The RDS was performed where the deep scleral stroma is prepared in 2 parts, folded and inserted under the lateral sides of the sclerectomy, and the Schlemm's canal is opened prior to deep scleral stroma preparation. Cataract was extracted by phacoemulsification through the same scleral opening. The follow-up for group A was 22.23 +/- 10.18 months and for group B, 25.36 +/- 10.12 months. RESULTS: Postoperative intraocular pressure (IOP) </= 21 mmHg was achieved for group A in 40.5% without antiglaucoma drugs and 94.6% with antiglaucoma drugs, and for group B in 66.3% and in 94.7% respectively. Mean IOP reduction was 7.02 +/- 6.35 mmHg (28.67%, P < 0.05) for group A and 5.26 +/- 3.72 mmHg (25.06%, P </= 0.05) for group B, while mean drug reduction was 1.97 +/- 1.09 (P < 0.01) and 2.14 +/- 0.95 (P </= 0.01) respectively. 5-Fluorouracil was used in 8 eyes of group A and in 5 eyes of group B. CONCLUSION: In the follow-up time during which the two groups were under study, the RDS was effective with a few complications, similar to the classic deep sclerectomy using implants or not, with the advantage, in our opinion, of a short learning curve.Clin Ophthalmo

Distinct gene subsets in pterygia formation and recurrence: dissecting complex biological phenomenon using genome wide expression data

<p>Abstract</p> <p>Background</p> <p>Pterygium is a common ocular surface disease characterized by fibrovascular invasion of the cornea and is sight-threatening due to astigmatism, tear film disturbance, or occlusion of the visual axis. However, the mechanisms for formation and post-surgical recurrence of pterygium are not understood, and a valid animal model does not exist. Here, we investigated the possible mechanisms of pterygium pathogenesis and recurrence.</p> <p>Methods</p> <p>First we performed a genome wide expression analysis (human Affymetrix Genechip, >22000 genes) with principal component analysis and clustering techniques, and validated expression of key molecules with PCR. The controls for this study were the un-involved conjunctival tissue of the same eye obtained during the surgical resection of the lesions. Interesting molecules were further investigated with immunohistochemistry, Western blots, and comparison with tear proteins from pterygium patients.</p> <p>Results</p> <p>Principal component analysis in pterygium indicated a signature of matrix-related structural proteins, including fibronectin-1 (both splice-forms), collagen-1A2, keratin-12 and small proline rich protein-1. Immunofluorescence showed strong expression of keratin-6A in all layers, especially the superficial layers, of pterygium epithelium, but absent in the control, with up-regulation and nuclear accumulation of the cell adhesion molecule CD24 in the pterygium epithelium. Western blot shows increased protein expression of beta-microseminoprotein, a protein up-regulated in human cutaneous squamous cell carcinoma. Gene products of 22 up-regulated genes in pterygium have also been found by us in human tears using nano-electrospray-liquid chromatography/mass spectrometry after pterygium surgery. Recurrent disease was associated with up-regulation of sialophorin, a negative regulator of cell adhesion, and <it>never in mitosis a</it>-5, known to be involved in cell motility.</p> <p>Conclusion</p> <p>Aberrant wound healing is therefore a key process in this disease, and strategies in wound remodeling may be appropriate in halting pterygium or its recurrence. For patients demonstrating a profile of 'recurrence', it may be necessary to manage as a poorer prognostic case and perhaps, more adjunctive treatment after resection of the primary lesion.</p

Factors influencing the accuracy of the SRK formula in the intraocular less power calculation

Several intraocular lens (IOL) power calculation formulas (either theoretical or empirical) are used to determine the emmetropic IOL power) The Sanders-Retzlaff-Kraff (SRK) linear regression formula is among the most widely recognized empirical ones. In the present study intraocular lens power calculation aiming at emmetropia was performed, using SRK formula, in 145 cataractous eyes undergoing lens implantation. The final refraction was evaluated at 8 to 12 months after surgery. The purpose of this study was the identification and quantitative evaluation of the factors which influence significantly the accuracy of SRK in the intraocular lens power calculation. The following factors were studied: (1) the error in preoperative biometry with regard to the difference between post and preoperative axial length measurements, (2) the position of the implantation of the intraocular lens (anterior versus posterior chamber), (3) the intraocular lens style, (4) the intraocular lens power level, (5) the preoperative corneal astigmatism, (6) the surgically induced corneal astigmatism, and (7) the postoperative astigmatism. Multiple regression and stepwise regression analysis showed a strong correlation (R2 = 0.65; p < 0.001) between postoperative refractive error (Rf) and error in preoperative biometry (delta AL), surgically induced corneal astigmatism (SIA) and postoperative astigmatism (Ap) only. This correlation is expressed by the following equation: Rf = 0.07 -2.55 delta AL -0.42 SIA + 0.34 Ap. This equation indicates the quantitative effect of each factor on the accuracy of the SRK formula, by defining the pattern of the fluctuations of the amount or state (myopic or hyperopic) of refractive error induced by changes of variables delta AL, SIA and Ap.Doc Ophthalmo

Treatment of toxoplasmosis. The treatment of toxoplasmic chorioretinitis

Toxoplasmosis is the commonest cause of inflammatory disease of the posterior segment of the eye. We treated 23 patients with acute toxoplasma chorioretinitis with sulfonamides, pyrimethamine and corticosteroids for a period of 4 weeks. All patients with acute disease had characteristic foci and a positive titer on the Sabin-Feldman dye test. In all patients, we observed clinical improvement within 2 weeks, but one patient with a lesion larger than 2 disc diameters improved after the third week. During the follow-up period ranging from 6 months to 6 years (mean 2.5 years), there have been four recurrences (17%). No serious side effects of treatment were observed in our patients.J Fr Ophtalmo

Self-healing of cementitious materials

89 σ.Εθνικό Μετσόβιο Πολυτεχνείο--Μεταπτυχιακή Εργασία. Διεπιστημονικό-Διατμηματικό Πρόγραμμα Μεταπτυχιακών Σπουδών (Δ.Π.Μ.Σ.) “Επιστήμη και Τεχνολογία Υλικών”Αντικείμενο της εργασίας, είναι η διερεύνηση της αυτο-ίασης (self-healing) τεχνητών ρωγμών σε κονιάματα τσιμέντου, τα οποία παρασκευάσθηκαν με χρήση εμπορικών προσθέτων. Οι σύγχρονες απαιτήσεις για την εκπλήρωση του σχεδιασμένου χρόνου ζωής των κατασκευών, έχουν ως αποτέλεσμα τη διάθεση σημαντικών πόρων για τη συντήρηση και την επισκευή αυτών. Δομικά στοιχεία με δυνατότητες αυτο-ίασης έχουν θετική επίδραση στο κόστος, στην ποιότητα και στη διάρκεια ζωής των δομικών έργων, ενώ θα πρέπει οπωσδήποτε να συνεκτιμούνται και τα αναμενόμενα περιβαλλοντικά οφέλη. Παρασκευάσθηκαν 7 διαφορετικές συνθέσεις κονιαμάτων με χρήση, τσιμέντου τύπου Ι, ασβεστολιθικής άμμου, ινών και δυο διαφορετικών εμπορικών προσθέτων. Ο λόγος νερού προς τσιμεντοειδή υλικά (W/B) και η ποσότητα του υπερρευστοποιητή βελτιστοποιήθηκαν με δοκιμαστικά αναμίγματα. Μετά τη συντήρηση των δοκιμίων για 28 ημέρες, γίνονται τεχνητές ρωγμές (μέσω δοκιμής σε διάρρηξη) και τα δοκίμια συντηρούνται σε νερό για κατάλληλο χρονικό διάστημα. Σε τακτά χρονικά διαστήματα (10, 20, 40 ημέρες) ελέγχεται η πρόοδος της αυτο-ίασης (κλείσιμο) των ρωγμών με στερεοσκόπιο. Ακόμη, με την τεχνική SEM προσδιορίζεται η φύση των ορυκτολογικών φάσεων που αναπτύσσονται στις ρωγμές και τελικά αξιολογούνται οι συνθέσεις που μελετήθηκαν. Παρατηρήθηκε σημαντική μείωση του πλάτους των ρωγμών, ενώ σε κάποιες συνθέσεις η αυτο-ίαση ήταν σχεδόν πλήρης. Χρήσιμο και αξιοποιήσιμο ακόμη στοιχείο είναι η χρονική εξέλιξη του φαινόμενου της αυτο-ίασης στις διάφορες συνθέσεις, ενώ η ηλεκτρονική μικροσκοπία SEM αξιοποιήθηκε ιδιαίτερα στην ερμηνεία του μηχανισμού δράσης των χρησιμοποιηθέντων προσθέτων. Τέλος, από τις πειραματικές μετρήσεις διευκρινίστηκε η συμβολή καθενός από τα πρόσθετα που χρησιμοποιήθηκαν στη διαδικασία της αυτο-ίασης των κο-νιαμάτων.The subject of this thesis is the self-healing of cementitious materials. Seven mortars (W/B=0.38) were prepared using cement type I, calcareous sand, polypropylene fibers, superplasticizer and two commercial additives. The first one was a crystalline waterproofing admixture (Penetron® Admix), while the second one was a special expansive hydraulic binder (DENKA CSA#20). Specimens were water cured for 28 days and then artificially cracked (crack width up to 120 μm) in order to clarify the self-healing process. After cracking, the specimens were water-cured and the residual crack width was measured after 10, 20 and 40 days using a stereomicroscope. In addition, the mineral phases that precipitated in the cracks were examined by SEM-EDS. Significant reduction of crack width was observed, while in some mixes the cracks were completely sealed. The mix containing 10% CSA and 1.5% Penetron showed the best self-healing behavior.Κωνσταντίνος Μ. Ασπιώτη

Pseudoexfoliation syndrome and diabetes mellitus

The frequency of pseudoexfoliation syndrome (PXF) was determined prospectively in 2 outpatient cohorts: a normal control group and a diabetic group with or without evidence of diabetic retinopathy. Four hundred and eighty-nine normal patients over the age of 50 years (group A) were compared with 325 diabetic patients of comparable age (group B). Within the diabetic cohort 121 patients did not exhibit signs of diabetic retinopathy, whereas the rest were suffering from either background diabetic retinopathy (143), or proliferative diabetic retinopathy (61). Pseudoexfoliation syndrome was present in 23.7% of patients in group A and 11% of patients in group B. Within the latter group, PXF was significantly less prevalent in the subgroup consisting of patients with proliferative diabetic retinopathy (3.2%). Correlating well to the age, PXF was significantly less prevalent for the age group 60-70 and greater than 70 for these patients. These results indicate that PXF occurs less frequently in diabetics with background diabetic retinopathy and even less so in the presence of proliferative diabetic retinopathy.Acta Ophthalmol (Copenh

Shock-Wave Generation In Transparent Media From Ultra-Fast Lasers

Laser interactions with bulk transparent media have long been investigated for material processing applications involving ablation and shock wave generation in both the nanosecond and femtosecond pulse width regimes 1. Shock waves have been studied in fused silica and other optical glasses but previously have been characterized by the morphology of the concurrent ablation. We perform ablation at distances of 30 meters using the non-linear self-channeling effect. Using silicon wafers as targets because of their clearly defined ablation zones, we examine the effect that the filament has on the thin SiO 2 layer coating the wafer\u27s surface. It is observed that the surface layer experiences a shock wave resulting from the explosive forces produced by the plasma. The use of several laser pulses in burst mode operation leads to the observation of multiple shock fronts in the material, and the possibility of shock wave addition for higher damage. Optical interferometry will be used to characterize the shock wave dynamics, using both traditional means of focusing in the near field and at 30 meters using propagating self-channeled femtosecond pulses. The novelty of using self-channeling laser pulses for shock wave generation has many implications for military applications. These experiments are to be performed in our secure test range using intensities of 10 14 W/cm 2 and higher incident on various transparent media. Interferometry is performed using a harmonic of the pump laser frequency. Experiments also include burst-mode operation, where a train of ultra-fast pulses, closely spaced in time, and novel new beam distributions, strike the sample

Timing of dislocated nuclear fragment management after cataract surgery

PURPOSE: To determine the timing of vitrectomy in patients with dislocated nuclear fragments after phacoemulsification and to correlate timing with visual outcomes. SETTING: University Eye Clinic of Ioannina, Ioannina, Greece. METHODS: This was a retrospective review of the records of 26 patients who had phacoemulsification at the University Eye Clinic of Ioannina over a 5-year period. The mean age of the 13 men and 13 women was 66.9 years (range 59 to 80 years). All patients had nucleus or nuclear fragment dislocation into the vitreous cavity during phacoemulsification and had vitrectomy and removal of the dislocated nucleus. The postoperative follow-up ranged from 3 to 9 months. RESULTS: Eight patients (30.8%) had vitrectomy at the time of phacoemulsification (Group A), 8 (30.8%) within 3 weeks (Group B), and 10 (38.5%) after more than 3 weeks (Group C). Patients in Group A did not develop complications, and 87.5% achieved a final visual acuity of 5/10 or better. In Group B, 4 patients (50%) developed moderate intraocular inflammation and 5 patients achieved a final visual acuity of 5/10 or better. Six patients in Group C (60%) had phacoanaphylactic glaucoma and 3 (30.0%), retinal detachment; 70.0% had a final visual acuity of 3/10 or worse. CONCLUSION: Early vitrectomy (fewer than 3 weeks postoperatively) was associated with better visual results, while late vitrectomy resulted in limited visual acuity in a high percentage of patients and increased the risk for glaucoma and retinal detachment.J Cataract Refract Sur