Argyrios Tzamalis

Improved reproducibility of retinal nerve fiber layer thickness measurements with the repeat-scan protocol using the Stratus OCT in normal and glaucomatous eyes

BackgroundOptical coherence tomography has become within the last years an established imaging technique with many applications in ophthalmology, and an important tool which contributes to earlier and more accurate diagnosis of glaucoma. As a consequence, detection sensitivity is highly valued. The aim of this study was to assess the reproducibility of peripapillary retinal nerve fiber layer (RNFL) thickness measurements by the Stratus Optical Coherence Tomograph (OCT) using the Fast- and Repeat-scan protocols in normal and glaucomatous eyes.MethodsIn the clinical setting, RNFL thickness measurements were obtained from a control group of 40 subjects, consisting of 20 normal volunteers and 20 glaucoma patients. One eye was randomly chosen from each subject, and underwent five RNFL thickness measurements with the Fast- and five with the Repeat-scan protocol, which was also based on the Fast-scan mode. Reproducibility was assessed by the intraclass correlation coefficient (ICC) and the coefficient of variation (CV) for the overall mean RNFL thickness and for each quadrant and clock hour of the peripapillary area.ResultsThe Repeat-scan protocol yielded higher ICC and lower CV values in all quadrants and clock hours of the peripapillary area, both in normal and glaucomatous subjects. The difference in CV values between Fast- and Repeat-scan protocol measurements reached statistical significance in the temporal quadrant (P = 0.021) and in clock hour sectors 8, 9 and 12 (P = 0.022, 0.017 and 0.03 respectively). ICC (and CV) for the temporal-, superior-, nasal- and inferior-quadrant RNFL thickness was: for the Fast-scan protocol, 0.913 (7.4%), 0.925 (6.97%), 0.828 (10.31%), 0.964 (4.89%) respectively; and for the Repeat-scan protocol, 0.965 (5.08%), 0.958 (5.26%), 0.906 (8.12%) 0.968 (4.6%) respectively.ConclusionsReproducibility of RNFL thickness measurements with the Fast- and Repeat-scan protocols by the Stratus OCT is proved to be very high both in normal and glaucomatous subjects. The Repeat-scan protocol shows higher ICC and lower CV values, statistically significant especially on the temporal side of the peripapillary area, which may indicate a higher reproducibility and greater agreement of measurements. These findings support the fact that the Repeat-scan protocol might be considered as a more precise method for evaluation of RNFL thickness.

Central corneal thickness during treatment with travoprost 0.004% in glaucoma patients.

PURPOSE Experimental studies demonstrated an alteration of corneal collagen structure by prostaglandin analogues. The possible effect of the prostaglandin F(2alpha) analogue travoprost 0.004% on the central corneal thickness (CCT) in newly diagnosed glaucoma patients was evaluated. METHODS Consecutive, interventional case series. Seventy-four patients/136 eyes with glaucoma were included in the statistical analysis. All patients received travoprost 0.004% (Travatan(R)) once daily in one or both eyes. CCT was measured by using noncontact optical low-coherence reflectometry prior to the treatment and after 6 and 12 months. RESULTS Mean CCT of all treated eyes (n = 136) was 546.71 +/- 34.63 mum at baseline, 535.14 +/- 34.78 mum after 6 months, and 532.38 +/- 34.18 mum after 12 months (ANOVA, P < 0.001). Ninety-five percent of all treated eyes showed a decrease of CCT. CCT reduction mainly developed within the first 6 months of the treatment period. After 12 months, a CCT reduction >30 mum occurred in 5.1% of all treated eyes. There was a significant correlation between the magnitude of corneal thinning and the initial CCT but not between corneal thinning and IOP reductions. CONCLUSIONS Topical therapy with the prostaglandin derivate travoprost is accompanied by a significant reduction of CCT within one year of treatment. Further clinical studies are needed to evaluate the possible long-term effects of prostaglandins on the CCT of glaucoma patients.

Self-retaining bicanaliculus stents as an adjunct to 3-snip punctoplasty in management of upper lacrimal duct stenosis: a comparison to standard 3-snip procedure.

Purpose: To evaluate the efficacy of self-retaining bicanaliculus stents when used as an adjunct to 3-snip punctoplasty in comparison with standard 3-snip procedure between fellow eyes. Methods: Prospective, randomized, comparative study. Thirty-two eyes of 16 consecutive patients with acquired, nontraumatic stenosis of the proximal lacrimal duct were randomly distributed into 2 equal study groups. Lower punctal stenosis was a standard prerequisite. Group A (16 eyes) received a simple 3-snip punctoplasty, while group B (16 fellow eyes) underwent a modified 3-snip punctoplasty combined with insertion of self-retaining bicanaliculus stents. Duration of follow ups: 6 months. Anatomical, functional, and subjective parameters were evaluated. Results: A statistically significant difference in anatomical success rates was observed in favor of group B (p = 0.011) 6 months postoperatively. Complete relief from epiphora was noted in 8 eyes of group B compared with 2 eyes of group A (p = 0.057). In regard to mixed (absolute and partial) functional success rates, group B exceeded with statistically significant difference (15 eyes group B vs. 6 eyes group A; p = 0.002). A nasolacrimal duct obstruction was subsequently diagnosed in 3 of the nonpatient eyes. Reintroduction of silicone tubes was required in 4 eyes of group B. Conclusions: The use of self-retaining bicanaliculus stents seems to improve anatomical, functional, and subjective scores when combined with standard 3-snip punctoplasty in patients with acquired upper lacrimal duct stenosis.

Diode laser cyclophotocoagulation versus cyclocryotherapy in the treatment of refractory glaucoma.

Purpose The aim of the present study was to evaluate the efficacy of diode laser cyclophotocoagulation (DCPC) and cyclocryotherapy (CCT) in the treatment of refractory glaucoma and compare the postoperative complications and discomfort rates. Methods In a prospective, randomized, controlled clinical study, 40 eyes of 40 patients with refractory glaucoma were randomly assigned in 2 groups of 20 eyes each to receive either DCPC or CCT. Patients underwent follow-up examinations on the first 3 days and then 1 week and 1, 3, 6, and 12 months after initial treatment. Complications and discomfort after treatment using a visual pain analogue scale were recorded. Results In the DCPC group, the mean intraocular pressure (IOP) decreased (p<0.05) from 44.3±16.4 mmHg preoperatively to 24.1±7.6 mmHg, 22.8±5.6 mmHg, and 22.5±5.1 mmHg 3, 6, and 12 months posttreatment, respectively. Regarding the CCT group, the mean IOP was reduced (p<0.05) from 46.5±10.4 mmHg to 26.6±12.2 mmHg, 21.2±7.7 mmHg, and 20.6±5 mmHg at the same time intervals. In the DCPC group, the mean IOP reduction was strongly correlated with the number of laser effects (r=0.65; p<0.01), but 35% needed retreatments. The mean postoperative pain was 5.6±2.9 (DCPC) vs 5.7±2.3 (CCT) (p=0.91). No severe complications were observed. Conclusions Both DCPC and CCT proved to be safe and effective IOP-lowering methods in patients with refractory glaucoma. Diode laser cyclophotocoagulation should be considered as the primary treatment option in refractory glaucoma using an individual treatment dosage.

Peripapillary Neovascular Membrane in a Young Pregnant Woman and Prompt Response to Ranibizumab Injections following Uneventful Delivery

Purpose: Occurrence of choroidal neovascularization (CNV) during pregnancy has been reported as a complication of presumed ocular histoplasmosis syndrome or punctuate inner chorioretinopathy. To our knowledge, idiopathic CNV (ICNV) during pregnancy has only been reported once in the relevant literature. Bevacizumab has been used for the treatment of ICNV in small case series. However, there is limited experience regarding the use of ranibizumab for the management of ICNV. Case Report: A 31-year-old woman in the eighth month of her second pregnancy was diagnosed with mild macular and papillary edema. She was followed up using biomicroscopy, fluorescein angiography (FA), and optical coherence tomography (OCT). After 3 months, visual acuity further deteriorated and funduscopy, FA and OCT findings revealed a juxtapapillary choroidal neovascular membrane (CNVM). After two ranibizumab injections, best-corrected visual acuity increased significantly, physiological macular anatomy was restored and no subretinal fluid was observed. Discussion: In this case report, we present a young pregnant patient with peripapillary ICNV and neurosensory detachment involving the macula, and treatment of the eye with intravitreal ranibizumab following uneventful delivery. Increased angiogenic factor levels associated with pregnancy may contribute to the onset of CNV although this relationship has to be investigated experimentally. The rapid response to ranibizumab suggests that this anti-VEGF agent may be an alternative treatment option in the management of peripapillary ICNV.

Acute postoperative Staphylococcus schleiferi endophthalmitis following uncomplicated cataract surgery: first report in the literature.

Purpose We report a rare case of acute postoperative Staphylococcus schleiferi endophthalmitis following an uneventful cataract extraction. Methods An 83-year-old woman underwent uneventful phacoemulsification without receiving the usual intracameral cefuroxime solution due to cephalosporin intolerance. Two days postoperatively, she presented with acute ocular pain and blurred vision in the operated eye. Ophthalmic examination revealed signs of acute keratitis and endophthalmitis. Corneal scrapes and vitreous taps were sent for cultivation and analysis. The patient received intravitreal antibiotics at the same time. Results Cultivation grew S schleiferi, a pathogen commonly found in dogs. Following microbiological report, the patient received a repeated intravitreal injection of 1 mg/0.1 mL vancomycin combined with fortified topical vancomycin drops. One week later, the inflammation subsided completely while the corneal ulcer healed and visual acuity improved dramatically. Further examination revealed the existence of the same pathogen in a specimen obtained from the dog owned by the patients family. Conclusions This description of S schleiferi endophthalmitis highlights the need to provide alternative intracameral antibiotic solution in the operating room and avoid direct contact with dogs during the first postoperative period after intraocular surgery.

Safety and efficacy of combined immunosuppression and orbital radiotherapy in thyroid-related restrictive myopathy: two-center experience

Purpose To evaluate the safety and efficacy of oral steroids when combined with long-term oral azathioprine (AZA) and orbital radiotherapy in patients with active thyroid-related restrictive myopathy. Methods A total of 88 patients from adnexal outpatient clinics of Bristol Eye Hospital, UK, and 2nd Department of Ophthalmology at Aristotle University of Thessaloniki, Greece, were enrolled in a retrospective, twin-center study. All patients were diagnosed with active thyroid eye disease and concomitant restrictive myopathy. Treatment included oral AZA, low-dose steroids, and orbital radiotherapy (20 Gy). Clinical activity scores as well as orthoptic assessments were consistently evaluated. Clinical activity scores, improved levels of diplopia, and single muscle excursions were considered major criteria for treatment success. Results Clinical success was achieved in 54 (61.4%), 57 (64.8%), and 61 (69.3%) patients at 3-, 6-, and 12-month time points, respectively, after the initiation of the combined treatment. At 18 months following initiation of treatment, the percentage of treatment success reached 73.9% (n = 65). Nine patients developed AZA-related side effects. In 4 patients the drug had to be discontinued. Conclusions Combined immunosuppression with orbital radiotherapy appears to reduce morbidity in patients with marked restrictive myopathy by improving major motility parameters such as diplopia and duction amplitude.

Decreased ocular pulse amplitude associated with functional and structural damage in open-angle glaucoma.

Purpose To assess the relationship of ocular pulse amplitude (OPA), as measured by dynamic contour tonometry (DCT), with structural and functional damage in patients with open-angle glaucoma (OAG). Methods In this cross-sectional, observational study, 242 eyes of 139 patients with OAG underwent Goldmann applanation tonometry (GAT), DCT, central corneal thickness (CCT) measurement, visual fields examination (Octopus, Haag Streit), and complete ophthalmologic examination. Linear regression analysis was used to analyze the effect of OPA, DCT, GAT, and CCT to the mean defect (MD) of the visual fields and to the vertical cup to disc ratio (CDR). Results Ocular pulse amplitude was the only variable that showed a significant association with MD (slope=–1.1, p=0.012), in contrast to GAT (p=0.98), DCT (p=0.32), and CCT (p=0.42). Ocular pulse amplitude was also negatively associated with CDR (slope=–0.028, p=0.0001). Additional multiple regression analysis revealed that OPA (R2=0.12, r=–0.25, slope=–0.02, p=0.033), GAT (r=–0.27, slope=–0.01, p=0.027), and CCT (r=–0.18, slope=–0.001, p=0.012) were statistically significantly correlated to CDR, while DCT was not (r=–0.20, slope=0.003, p=0.46). Ocular pulse amplitude did not differ statistically significantly (p=0.93) between eyes with (2.79±1.42) and without (2.77±1.21) prior trabeculectomy. No statistically significant difference of OPA was observed between diagnosis groups (p=0.255). Conclusions Decreased OPA seems to be correlated with increased glaucomatous functional and structural damage in OAG. Assessment of OPA by DCT could therefore serve as an important additional parameter in the evaluation of glaucoma patients.

Training of Resident Ophthalmologists in Cataract Surgery: A Comparative Study of Two Approaches

Purpose. To evaluate and compare the efficacy of two different training methods in resident-performed phacoemulsification surgery. Methods. 502 eyes of 467 patients who underwent resident-performed phacoemulsification were included in the study by reviewing their medical records. Residents were allocated into two groups according to the method applied during their training in cataract surgery; Group A included residents that were trained with the “step-by-step” method and Group B those trained with the “one-step” method. Primary outcome was the incidence of main complications, defined as posterior capsular ruptures and/or zonular dehiscence with vitreous loss. Results. Each resident performed a median of 63 phacoemulsification surgeries. A statistically significant difference (p = 0.0032) was noted in the main complications rate between the two groups, yielding a mean of 17.3% in Group A and 7.25% in Group B. Other intraoperative complications were not shown to differ statistically significantly between study groups (p > 0.05). Among the first 40 surgeries of each resident, main complications rate differed also statistically significantly (p = 0.0048) between Group A (21.67%) and Group B (8.5%), while a better surgical performance-yielding statistical significance in Group A (p = 0.017) was indicated in both groups between the 20th and the 30th procedure. Conclusions. Training in cataract surgery using the “one-step” method may lead to an improvement in surgical competency, when measured by complications rates and, therefore, to significantly better quality of training for resident ophthalmologists.

Association of Ocular Hypotensive Medication Types with Dynamic Contour Tonometry and Goldmann Applanation Tonometry Measurements in a Glaucoma and Ocular Hypertensive Population

PURPOSE The aim of this study was to evaluate the association between different intraocular pressure (IOP)-lowering medications and IOP measurements by dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT) in a glaucoma and ocular hypertensive population. METHODS In a prospective, observational case series study, 410 eyes from 410 consecutive patients with open-angle glaucoma (OAG) or ocular hypertension (OHT), were enrolled. All eyes included in the study received unaltered ocular hypotensive medication for at least 6 months before IOP measurement. All eyes underwent 2 GAT and 3 DCT measurements, and their means were used for the analysis. RESULTS DCT-GAT IOP difference (ΔIOP) did not differ statistically significantly (P=0.49) between OAG and OHT group yielding a mean±SD of 4.26±2.02 mmHg and 4.41±2.25 mmHg, respectively. The number of IOP-lowering agents did not have any statistically significant influence on ΔIOP (p=0.177), DCT (P=0.28) and GAT (P=0.13) measurements. A statistically higher ΔIOP was revealed in monotherapy patients receiving Carbonic Anhydrase Inhibitors (CAIs) (ΔIOP=5.75 mmHg) in comparison to patients receiving Prostaglandin Analogs (ΔIOP=4.09 mm Hg) or beta Blockers (ΔIOP=3.78 mmHg) as single topical therapy (F=4.373, P=0.005). Eyes treated with CAIs as a part of the ocular hypotensive therapy yielded a significantly greater ΔIOP (P=0.0035) than those without CAIs in the therapeutic schema. CONCLUSIONS The difference between DCT and GAT IOP measurements is found to be statistically significantly higher in patients receiving CAIs either as monotherapy or as a part of a combined ocular hypotensive treatment, while DCT and GAT readings remain unaffected. The type of diagnosis and the number of ocular hypotensive medications had no statistically significant influence on ΔIOP.