Development of ocular hypertension secondary to tamponade with light versus heavy silicone oil: A systematic review.

Aim: The intraocular silicone oil (SO) tamponades used in the treatment of retinal detachment (RD) have been associated with a difference ocular hypertension (OH) rate. To clarify, if this complication was associated to use of standard SO (SSO) versus heavy SO (HSO), we performed a systematic review and meta‑analysis of comparative study between two kind of SO (standard or light vs. heavy) for the treatment of RD and macular hole, without restriction to study design. Materials and Methods: The methodological quality of two randomized clinical trials (RCTs) were evaluated using the criteria given in the Cochrane Handbook for Systematic Reviews of Intervention, while three non‑RCTs were assessed with the Newcastle– Ottawa Scale and Strengthening the Reporting of Observational Studies in Epidemiology checklists. We calculated Mantel–Haenszel risk ratio (RR) with 95% confidence intervals (95% CIs). The primary outcome was the rate of patients with OH treated with SSO compared to HSO. Results: There were a higher number of rates of OH in HSO compared to SSO. This difference was statistically significant with the fixed effect model (Mantel–Haenszel RR; 1.55; 95% CI, 1.06–2.28; P = 0.02) while there was not significative difference with the random effect model (Mantel–Haenszel RR; 1.51; 95% CI, 0.98–2.33; P = 0.06). Conclusion: We noted a trend that points out a higher OH rate in HSO group compared to SSO, but this finding, due to the small size and variable design of studies, needs to be confirmed in well‑designed and large size RCTs.

Quality of vision in patients implanted with aspherical and spherical intraocular lens: Intraindividual comparison.

Aims: To compare the quality of vision in pseudophakic patients implanted with aspherical and spherical intraocular lenses (IOLs). Materials and Methods: Randomized prospective longitudinal intrapatient comparison between aspherical and spherical IOLs performed on 22 patients who underwent bilateral cataract surgery. Best corrected visual acuity, subjective contrast sensitivity, Strehl ratio and spherical aberrations (SA), and higher order wavefront aberrations for a 3.5 mm and a 6.0 mm pupil were measured after 3 months of cataract surgery. Results: SA (Z4,0) decreased significantly in eyes with aspherical IOL implant (P = 0.004). Modulation transfer function (MTF) and point spread function (PSF) resulted no significant difference between the two groups (P = 0.87; P = 0.32). Conclusion: Although the SA is significantly lower in eyes implanted with aspherical IOL, the quality of vision determined with MTF and PSF does not significantly differ for subjective and objective parameters that were analyzed.

Analysis of photoastigmatic keratectomy with the cross-cylinder ablation.

Aim: The aim was to evaluate the safety and efficacy of the “cross-cylinder” technique in the correction of astigmatism. Setting and Design: A prospective interventional study from a university eye department was conducted. Material and Methods: The photoastigmatic refractive keratectomy (PARK) using the “cross-cylinder” technique was performed in 102 eyes of 84 patients with at least 0.75 D of astigmatism. The study population was divided into two groups: in the first group the preoperative astigmatic power ranged from –0.75 D to –3.00 D (group 1), in the second group it ranged from –3.25 D to –6.00 D (group 2). Group 1 included 82 eyes of 67 patients (29 males and 38 females) with a mean cylinder power of –1.90 ± 0.63 D, group 2 included 20 eyes of 17 patients (13 males and 4 females) with a mean cylinder power of -4.28 ± 0.76 D. All eyes were targeted for emmetropia. The results were evaluated using Calossi's vector analysis method. Six-month postoperative outcomes are presented. Results: Six months after PARK the mean sphere for the entire cohort was +0.28 ± 0.75 D (range +2.5 to –2 D), the mean cylindrical power was +0.33 ± 0.51 D (range +2.5 to –1.25 D) and the mean spherical equivalent refraction was +0.73 ± 0.81 D (range +1.75 to –2 D). Conclusions: The cross-cylinder technique may be safely used with predictable results for the correction of astigmatism.

Primary 23-gauge sutureless vitrectomy for rhegmatogenous retinal detachment.

Aims: To report a prospective non-comparative consecutive interventional study on the safety and efficacy of 23-Gauge transconjunctival sutureless pars plana vitrectomy for primary rhegmatogenous retinal detachment (RRD). Materials and Methods: Fifty eyes of 50 consecutive patients were recruited between June 2007 and January 2008. All surgeries were performed using the one-step 23-Gauge system with angled incisions. The surgical protocol consisted of a minimum of eight clinical visits: baseline, 1 day, 1 week, 1-, 3- and 6- months after the initial surgery. The endpoints were anatomical, functional results and complications arising from the surgery. Results: Anatomical success was achieved in 82% of cases (41 out of 50) with single surgery and rose to 98% (49 out of 50) with additional surgery. Mean visual acuity improved from logMAR 0.48(SD 0.36) to 0.26(SD 0.31), P < 0.001. Two cases with ocular hypotony, defined as an intraocular pressure ≤ 6mmHg, that were associated with a choroidal detachment were seen. Conclusions: Acceptable anatomical and functional success rates can be achieved with primary 23-Gauge transconjunctival sutureless vitrectomy for RRD. We found that the approach technique is different from conventional vitrectomy and the complications arising from post surgical hypotony and leakage from sclerotomies are potentially higher compared to 20-Gauge vitrectomy.