Refractive change following pseudophakic vitrectomy: a retrospective review

Background To assess the occurrence and magnitude of refractive change in pseudophakic eyes undergoing 20 gauge pars plana vitrectomy without scleral buckling and to investigate possible aetiological factors. Methods Retrospective case note review of 87 pseudophakic eyes undergoing 20 gauge pars plana vitrectomy for a variety of vitreo-retinal conditions over a three-year period. Anterior chamber depth (ACD) was measured before and after vitrectomy surgery in 32 eyes. Forty-three pseudophakic fellow eyes were used as controls. Results Eighty-seven eyes (84 patients) were included in the study. Mean spherical equivalent refraction prior to vitrectomy was -0.20 dioptres, which changed to a mean of -0.65 dioptres postoperatively (standard deviation of refractive change 0.59, range-2.13 to 0.75 dioptres) (p < 0.001). Sixty-one of the 87(70%) eyes experienced a myopic shift and 45(52%) eyes had a myopic shift of -0.5 dioptres or more. Mean fellow eye refraction was -0.19 dioptres preoperatively and -0.17 dioptres postoperatively (p = 0.14)(n = 37) Mean ACD preoperatively was 3.29 mm and postoperatively 3.27 mm (p = 0.53) (n = 32) and there was no significant change in ACD with tamponade use. Regression analysis revealed no statistically significant association between changes in anterior chamber depth, as well as a wide variety of other pre-, intra and postoperative factors examined, and the refractive change observed. Conclusion Significant refractive changes occur in some pseudophakic patients undergoing 20 g pars plana vitrectomy. The mean change observed was a small myopic shift but the range was large. The aetiology of the refractive change is uncertain

Influence of silicone oil tamponade after vitrectomy on intraocular pressure [Tamponada silikonskim uljem i njezin utjecaj na vrijednosti intraokularnog tlaka]

The aim of this prospective study was to determine the possible influence of the silicone oil tamponade after vitrectomy on the early intraocular pressure (IOP) elevation, which is a major risk factor for developing secondary glaucoma in patients with vitreal and retinal proliferative changes. The research included 110 patients which were allocated in three groups according to the medical history data. The surgical procedures were performed at the Eye Clinic, University of Zagreb School of Medicine. The control group comprised 40 patients who underwent vitrectomy with air or saline solution tamponade. The second group consisted of 40 patients with retinal detachment and proliferative retinopathy who had vitrectomy with silicone oil tamponade and the third group were 30 patients with diabetic retinopathy who underwent vitrectomy and tamponade with silicone oil. The intraocular pressure was measured and gonioscopy was performed in all patients one month before and after vitrectomy. The results showed that there is no statistically significant difference among IOP values before and after vitrectomy in the control group (p = 0.104) as well as in the preoperative IOP values among all three groups of patients. The data analysis determined that in both groups of patients with silicone oil tamponade after vitrectomy, there is a statistically significant difference in IOP values one month after the surgical procedure (p = 0.000). The mean IOP values in those patients a month after vitrectomy were significantly higher compared to the control group (p < 0.05). Comparison of the IOP one month after vitrectomy between the patients with retinal detachment and those with diabetic retinopathy showed no statistically significant difference (p = 0.331) but the qualitative analysis showed that the IOP one month after vitrectomy was 2 mmHg higher in the diabetic retinopathy group. The results suggest that there is no difference in angle width before and after vitrectomy among different groups of patients. Emulsified silicone oil was confirmed in 18% of patients in the retinal detachment group. In 17% of patients in the diabetic retinopathy group the emulsified oil was found in the angle, whereas a 10% of patients had neovascularization of the angle one month after vitrectomy. The IOP elevation in the early postoperative course may be caused by intravitreal instillation of the silicone oil after vitrectomy. Emulsification of the silicone oil may lead to the early IOP rise; especially in the diabetic patients with angle neovascularization which itself can additionally accelerate the development of the secondary glaucoma

A Review of Innovations in Rhegmatogenous Retinal Detachment Surgical Techniques.

Rhegmatogenous retinal detachment (RRD) requires surgical intervention for its repair. There are variable techniques used for this purpose, and they are all being continuously refined. In this review, we detail the recent innovations in surgical management of RRD and proliferative vitreoretinopathy (PVR)

Comparison of Three Different Techniques of Inverted Internal Limiting Membrane Flap in Treatment of Large Idiopathic Full-Thickness Macular Hole.

Purpose: To evaluate and compare three different techniques of inverted internal limiting membrane (ILM) flap in the treatment of large idiopathic full-thickness macular hole. Methods: In a comparative interventional case series, 72 eyes from 72 patients with large (\u3e 400 µm) full-thickness macular hole were randomly enrolled into three different groups: group A - hemicircular ILM peel with temporally hinged inverted flap; group B - circular ILM peel with temporally hinged inverted flap; and group C - circular ILM peel with superior inverted flap. Best-corrected visual acuity (BCVA), anatomical closure rate, and ellipsoid zone (EZ) or external limiting membrane (ELM) defects were evaluated preoperatively, at week 1, and months 1, 3 and 6 after surgery. Results: There were 24 eyes in group A, 23 in group B, and 25 in group C. In all three groups, larger diameter macular hole was associated with worse preoperative visual acuity (r=0.625, P\u3c0.001). Mean BCVA improved significantly in all three groups 6 months after surgery (0.91vs 0.55, p\u3c0.001). 6 months after surgery, mean BCVA improved from 0.91 logMAR to 0.52±0.06 in group A, 0.90 to 0.53±0.06 in group B, and 0.91 to 0.55±0.11 in group C. In group A vs. B vs. C, improvement of BCVA was 0.380±0.04 vs. 0.383±0.04 vs. 0.368±0.11 logMAR, with no statistically significant difference between groups (P=0.660). The rate of successful hole closure was 87.5% vs. 91.3% vs. 100%. Although the closure rate was 100% in Group C (circular ILM peel with superiorly hinged inverted flap), this difference was not statistically significant (P=0.115). Conclusion: ILM peel with an inverted flap is a highly effective procedure for the treatment of large, full-thickness macular hole. Different flap techniques have comparable results, indicating that the technique can be chosen based on surgeon preference

Rapid and Accurate Pressure Sensing Device for Direct Measurement of Intraocular Pressure.

PurposeIntraocular pressure (IOP) is the primary modifiable risk factor for glaucoma. Current devices measure IOP via the dynamic response of the healthy cornea and do not provide the accurate IOP measurements for patients with altered corneal biomechanics. We seek to develop and test an accurate needle-based IOP measurement device that is not cornea dependent.MethodsOur device combines a high-resolution pressure microsensor with 30- and 33-gauge Luer lock needles to provide IOP measurements via a microcontroller and USB interface to a computer. The device was calibrated in a membrane chamber and then tested and validated in the anterior chamber and post-vitrectomy vitreous chamber of rabbit eyes. The results were compared to Tonopen readings across a pressure range of 0 to 100 mm Hg, imposed in increments of 10 mm Hg.ResultsBoth the needle based sensor device and the Tonopen demonstrated a linear relationship with changes in imposed pressure. The Tonopen was found to consistently underestimate the IOP both in the anterior and vitreous chambers. The Tonopen exhibited a significantly greater error than our needle-based sensor device. With increased pressure (&gt;30 mm Hg), the error of the Tonopen increased, whereas the error of our device did not. The 30-gauge needle produces an insignificant improvement in accuracy over the 33-gauge needle.ConclusionsA needle-based sensor device enables accurate IOP measurements over a broad range of induced IOP.Translational relevanceDirect measurement of IOP in the anterior chamber circumvents the influence of corneal parameters on IOP measurement

Ocriplasmin in the treatment of vitreomacular traction in a patient with central retinal vein occlusion. a case report

Aim: To investigate the efficacy of intravitreal injection of ocriplasmin (JETREA®) in the treat-ment of vitreomacular traction (VMT). Materials and Methods: An 81-year-old man with VMT associated with central retinal vein occlusion in his left eye, was treated with a single intravitreal injection of ocriplasmin (25 μg). Best corrected visual acuity (BCVA), ocular fundus, and optical coherence tomography were examined before and after treatment. Results: Complete release of VMT produced a reduction of central macular thickness, ranging from 459 to 141 μm. BCVA remained stable. Discussion and Conclusions: The use of ocriplasmin was effective in the treatment of VMT. Ocriplasmin represents a valid alternative to conventional pars plana vitrec-tomy

Handheld forward-imaging needle endoscope for ophthalmic optical coherence tomography inspection

We report the narrowest to-date (21 gauge, 820-µm-diam) handheld forward-imaging optical coherence tomography (OCT) needle endoscope and demonstrate its feasibility for ophthalmic OCT inspection. The probe design is based on paired-angle-rotation scanning (PARS), which enables a linear B-scan pattern in front of the probe tip by using two counterrotating angle polished gradient-index (GRIN) lenses. Despite its small size, the probe can provide a numerical apertune (NA) of 0.22 and an experimental sensitivity of 92 dB at 0.5 frames. The feasibility of retinal imaging is tested on enucleated ex vivo porcine eyes, where structural features including remnant vitreous humor, retina, and choroid can be clearly distinguished. Due to its imaging quality comparable to a commercial OCT system and compatibility with the current ophthalmic surgery standard, the probe can potentially serve as a better alternative to traditional visual inspection by white light illumination during vitreoretinal surgery (e.g., vitrectomy)