Stanislao Rizzo

Autologous plasmin for pharmacologic vitreolysis prepared 1 hour before surgery.

Purpose: To evaluate the safety and efficacy of intravitreal injection of autologous plasmin enzyme (APE) in inducing a posterior vitreous detachment (PVD). APE was obtained by a modified method 1 hour before surgery. Methods: APE was obtained by centrifugation of autologous whole blood from the patients 1 hour before surgery and by incubation with streptokinase. APE was injected in the vitreous cavity 20 minutes before surgery. This procedure was applied for 20 patients who underwent vitrectomy for macular pucker, macular hole, and macular edema due to vitreoretinal traction. The status of PVD was graded intraoperatively. The plasmin concentration obtained by this method and the plasminogen titer of the plasma from each patient were compared. Activated partial thromboplastin time was controlled before surgery and 1, 6, 12, and 24 hours after surgery to evaluate alteration of the coagulation due to systemic absorption of the plasmin. Results: Preparation of APE was easy and took on average 45 minutes for all patients. A PVD with an evident Weiss ring was observed during surgery in 17 eyes (85%). The average plasmin activity was 0.26 IU/0.2 mL activated plasma. The partial thromboplastin time did not show any alteration in any of the patients with respect to preoperative values. Conclusion: APE obtained by this method can lead to a PVD and facilitate the complete remotion of vitreous cortex. The intravitreal injection does not lead to alteration of systemic blood coagulation.

Incidence of retinal detachment after small-incision, sutureless pars plana vitrectomy compared with conventional 20-gauge vitrectomy in macular hole and epiretinal membrane surgery.

Purpose: The purpose of this study was to evaluate the incidence of retinal detachment (RD) after a small-incision, sutureless vitrectomy compared with conventional 20-gauge vitrectomy in macular hole and epiretinal membrane surgery and to investigate the clinical features and possible causative agents. Methods: The authors performed a computerized database analysis to retrospectively identify all patients who underwent vitrectomy at our institution between March 2001 and March 2009 for epiretinal membrane and macular hole. The authors further investigated the clinical features of patients who showed RD within 6 months postoperatively in the study eye. The incidence rate and clinical features of the affected eyes were analyzed. Results: During the study period, 2,432 vitrectomies were performed for epiretinal membrane and macular hole. The incidence of RD was 1.7% (31 of 1,862) after sutureless 25- or 23-gauge vitrectomy and 1.2% (7 of 570) after conventional 20-gauge vitrectomy. The difference was not statistically significant. Moreover, the difference between 25-gauge surgery (28 of 1,580) and 23-gauge surgery (3 of 282) was not statistically significant. In 9 of 38 cases (24%), the RD was probably attributable to the underlying pathology (e.g., an unclosed macular hole and reopening of preexisting retinal tears). Twenty-one eyes (76%) presented new retinal tears that were not related to the sclerotomies in both groups. Conclusion: The incidence of RD after macular surgery is not increased in small-gauge, sutureless vitrectomy compared with the standard 20-gauge procedure. In most cases, the RD is not caused by the surgical technique itself but caused by new retinal breaks.

General Pathophysiology of Macular Edema

Macular edema represents a common final pathway for many ocular diseases. Related ocular disorders include diabetic retinopathy, vascular occlusions, postsurgical situations, and uveitic diseases. The key pathophysiologic process is a breakdown of the blood-retinal barrier, normally preventing water movement in the retina, thus allowing fluid to accumulate in the retinal tissue via special water fluxes. Inflammatory processes and an increase in vascular permeability play a central role. Different mechanisms, complicated by ischemic conditions, interact in a complex network. Key factors are angiotensin II, prostaglandins, and the vascular endothelial growth factor. The various pathogenetic mechanisms and their contribution to the edema process are described in detail in this article.

The Argus II Retinal Prosthesis: 12-Month Outcomes from a Single-Study Center

PURPOSE To study the anatomic and functional outcomes of Argus II Retinal Prosthesis System implantation in patients with retinitis pigmentosa. DESIGN Interventional case series. METHODS The study population included 6 patients with visual acuity no better than light perception. After the Argus II Retinal Prosthesis System was implanted, complications and anatomic and functional results were studied. The main outcome measures were mobility, square localization, direction of motion, grating visual acuity, and Goldmann visual field, all of which were assessed. Optical coherence tomography was performed. RESULTS Implantation of the Argus II Retinal Prosthesis System was safely performed in all patients. One patient experienced postoperative elevation in intraocular pressure, which was controlled medically. In 1 patient, moderate detachment of the choroid occurred postoperatively, and it resolved spontaneously. One patient withdrew from the study. Wound dehiscence, endophthalmitis or retinal detachment was not observed. All patients were able to locate a bright light on the ceiling and a dark line on the floor after the surgery. Performance in square localization tests improved in 4 patients, and direction of motion improved in 3 patients. One patient achieved grating visual acuity. Goldmann visual field test results improved in all patients. CONCLUSIONS The patients showed improvement in visual tasks after the surgery, and the device was well tolerated and functional over a 1-year follow-up period. A rigorous patient-selection process is necessary to maximize patient compliance with the rigorous follow-up testing schedule. Both patients and medical staff should be prepared for a lengthy, arduous rehabilitation process.

Successful treatment of persistent macular holes using "heavy silicone oil" as intraocular tamponade.

Background: Silicone oil tamponade has been suggested in the treatment of persistent macular hole, but visual outcome is often poor. We describe two patients who underwent reoperation for persistent macular hole using “heavy silicone oil” (HSO) tamponade. Methods: Two patients who underwent vitrectomy, removal of the posterior vitreous cortex, peeling of the internal limiting membrane, and long-acting gas tamponade had persistent macular hole 3 months after surgery. The patients underwent reoperation using an HSO (Oxane Hd, Bausch & Lomb) as internal tamponade. This tamponade did not require postoperative posturing and was removed after 3 months. Optical coherence tomography (OCT) was performed, and visual outcome was determined. Results: OCT images showed that the HSO bubble conformed well with the retinal surface in the foveal region. Closure of the macular hole was achieved in both patients. Visual acuity increased from 20/100 to 20/40 in Patient 1 and from 20/600 to 20/100 in Patient 2. Conclusion: HSO can be a useful tool in the treatment of persistent macular hole. OCT images showed that the tamponade was effective in the upright position in the foveal region. OCT allowed determination of the time of tamponade removal according to the anatomical stage of hole closure.

A pilot study on the use of silicone oil–RMN3 as heavier-than-water endotamponade agent

AimsThis work was conducted to report an interventional non-comparative pilot study using Oxane HD, a mixture of ultra-purified silicone oil and RMN3, a partially fluorinated olefin, as heavier-than-water internal tamponade.MethodsTwenty-eight consecutive patients were recruited for this study. Indications included recurrent retinal detachment (RD) with proliferative vitreoretinopathy (PVR) (stage ≥C2) arising from inferior or posterior tears, recurrences after vitreoretinal surgery, penetrating trauma and combined rhegmatogenous and choroidal detachment. The patients underwent a pars plana vitrectomy, membrane peeling, and Oxane HD was used as long-term internal tamponade.ResultsOxane was removed after 88 days (range 45–96 days) and exchanged with BSS in five eyes, long-acting gas in 14 eyes and with silicone oil in nine eyes. Retinal reattachment was achieved in 15 eyes. The overall anatomical success rate obtained using Oxane HD was 53.5%. In 15 patients with previous marked scleral buckling, the success rate was 26%: in nine patients recurrent RD occurred in the inferior sector, in five patients new tears were detected in the lower sectors; membrane formation was observed in 15 eyes. In 13 patients without marked scleral indent, the success rate was 84.6%. There was no evidence of dispersion and excessive inflammation.ConclusionOxane HD may be a useful tool in complicated RD with large inferior breaks, inferior PVR or combined rhegmatogenous, and choroidal detachment without marked scleral buckling, which put the eye profile out of shape, led to a higher failure rate and reduced the tamponading effectiveness of Oxane HD.

Heavy silicone oil versus standard silicone oil in as vitreous tamponade in inferior PVR (HSO Study): interim analysis.

Purpose:  The Heavy Silicone Oil versus Standard Silicone Oil Study (HSO study) is designed to answer the question whether a heavier‐than‐water tamponade improves the prognosis of eyes with proliferative vitreoretinopathy (PVR) of the lower retina.

Effects of strabismus surgery on corneal topography

BACKGROUND Changes in refraction follow surgery on the extraocular muscles. We examined corneal topography before and after medial or lateral rectus muscle recession using a computer-assisted topographic analysis system. METHODS A total of 36 patients (52 eyes) were examined. Measurements were taken 1 day before surgery and 1, 15, and 30 days after surgery. RESULTS A significant change in astigmatic power was detected 1 day after surgery in the meridian of the recessed muscle, evidencing a localized flattening of the cornea. Induced astigmatism decreased over time. At 30 days following surgery, 6% of patients evidenced a residual change higher than 1 diopter (D); 12% evidenced a residual change higher than 0.5 D. CONCLUSION The increase of astigmatic power recorded 1 day after surgery is higher for medial rectus muscle recession than for lateral rectus muscle recession. Corneal topography changes, located mainly in the meridian of the recessed muscle and the optical zone, are greatly reduced or gone within 1 month of surgery.

Safety of Submacular Suprachoroidal Drug Administration via a Microcatheter: Retrospective Analysis of European Treatment Results

Purpose: To investigate the safety and feasibility of using a microcatheter for drug delivery in the suprachoroidal space in eyes with advanced, exudative, age-related macular degeneration (AMD) unresponsive to conventional therapy. Procedures: A unique microcatheter was used to deliver a drug combination consisting of bevacizumab and triamcinolone to the submacular suprachoroidal space. Twenty-one eyes of 21 patients with choroidal neovascularization (CNV) secondary to advanced, exudative AMD were followed over a 6-month postprocedure period. Results: The microcatheter was successfully and atraumatically inserted into the suprachoroidal space of all eyes. No serious intraoperative or postoperative complications including suprachoroidal hemorrhages were encountered. Postsurgically, complications consisted of 1 eye experiencing a transient elevation in intraocular pressure at 3 months, which was medically controlled, and 2 eyes (10.5%) with an apparent increase in nuclear sclerotic cataracts. Conclusions: Suprachoroidal drug administration was achieved without serious complication using a novel microcatheter. Direct drug delivery to the choroid can potentially increase local tissue drug levels and drug efficacy for the treatment of AMD and other diseases associated with CNV.

Safety profile of ocriplasmin for the pharmacologic treatment of symptomatic vitreomacular adhesion/traction.

Purpose: To report the safety of intravitreal ocriplasmin injection based on 2 Phase 3 clinical trials in patients with symptomatic vitreomacular adhesion/vitreomacular traction, including when associated with full-thickness macular holes. Methods: Safety analyses were based on 2 completed Phase 3 studies assessing intravitreal ocriplasmin injection. Adverse events (AEs), serious AEs, and suspected adverse drug reactions are reported. The authors also report AEs of special interest from 8 other completed Phase 2 studies and 2 ongoing studies. Results: A total of 465 eyes were injected with ocriplasmin (125 µg), and 187 eyes were treated with placebo injection in Phase 3 studies. Overall AE rate was 69.0% in the placebo group and 76.6% for ocriplasmin-treated patients. Most AEs were in the study eye, mild or moderate in severity, and transient. All suspected adverse drug reactions were ocular; the majority was nonserious, of mild intensity, and transient. Conclusion: Intravitreal ocriplasmin injection provides a generally well-tolerated pharmacologic treatment option for patients with symptomatic vitreomacular adhesion/vitreomacular traction, including when associated with full-thickness macular holes ⩽400 µm in diameter.