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PurposeTo evaluate outcomes of small-gauge pars plana vitrectomy (PPV) for the treatment of rhegmatogenous retinal detachment (RD) without scleral-depressed shaving of the vitreous base.MethodsRetrospective, consecutive case series. Surgical technique included small-gauge PPV (25G, 23G, 25G+ or 27G) and wide-angle vitrectomy viewing system in all cases. No cases were excluded based on the level of complexity of RD. Outcome measures were retinal reattachment rates and Snellen visual acuity (best-corrected visual activity [BCVA]).Results312 eyes of 301 patients, mean age 60.8 years, and mean follow-up 23.1 months. Baseline characteristics included macula-off RD in 207 (66%) eyes, psudophakia in 124 (40%) eyes, high myopia in 74 (24%) eyes and giant retinal tear in 14 (5%) eyes. The retina was reattached with one procedure in 296 (95%) eyes. Final retinal reattachment was achieved in 310 (99%) eyes. The BCVA at baseline was >20/40 in 76 (24%) eyes, 20/50–20/100 in 48 (15%) eyes, 20/200–20/400 in 46 (15%) eyes and 20/40 in 168 (54%) eyes, 20/50–20/100 in 60 (19%) eyes, 20/200–20/400 in 49 (16%) eyes and ConclusionSmall-gauge PPV without scleral-depressed vitreous base shaving can be associated with good anatomical and visual outcomes. Case selection based on the complexity of RD may not be required when considering small-gauge PPV.

Objective: To evaluate the staining characteristics of bromphenol blue used during vitreoretinal surgery in humans. Patients and methods: 13 patients with epiretinal membranes were included. Before and after surgery a complete clinical examination including best corrected visual acuity, funduscopy, fluorescein angiography, OCT (Stratus), Goldmann perimetry and multifocal ERG as well as photography of the macular area was performed. Bromphenol blue was used in concentrations of 0.2% in most patients. Removed epiretinal tissue was evaluated using electron microscopy. Results: Using dye concentrations of 0.2% a good demarcation of epiretinal membranes was seen in 11/13 patients. Staining of vitreous remnants at the vitreous base was seen in all patients. No dye-related adverse events were seen during follow-up in the functional tests (VA, ERG, perimetry) performed. Histological evaluation of epiretinal membranes showed unremarkable aspects of epiretinal cellular layers and unremarkable retinal surface of the internal limiting membrane (ILM). Conclusion: Bromphenol blue appears to be a very helpful and safe tool in posterior segment surgery. The staining characteristics need to be further evaluated in prospective study settings and larger numbers of patients.

To evaluate rates of vitreous relapse among retinoblastoma patients treated with primary chemotherapy and assess diode laser as a potential risk factor for relapse.Retrospective review of all patients treated with primary chemotherapy at a large ocular oncology centre. Eyes that developed vitreous relapse were coded with regard to Reese-Ellsworth Group, laterality, time to relapse, type of relapse (vitreous base or non-vitreous base relapse), treatments used (including adjuvant diode laser), and ocular preservation. Individual tumour foci treated with laser hyperthermia were also coded for laser parameters including power settings, number of treatments, and concomitant administration of systemic chemotherapy (chemothermotherapy).15 of 106 eyes (14.15%) developed vitreous relapse over a 6 year period. Mean time to relapse was 7.2 months after chemotherapy was completed. Five cases (33%) were of the vitreous base variety. Ocular salvage was attempted in 11 cases using a variety of methods; one patient was lost to follow up. Six of the remaining 10 eyes (60%) were salvaged. Eight of 38 eyes (21%) treated with systemic chemotherapy and laser hyperthermia developed vitreous relapse compared with seven of 68 eyes (10%) treated with primary chemotherapy alone (p0.005). Laser settings, number of hyperthermia treatments, and the concomitant use of systemic chemotherapy (chemothermotherapy) were not associated with higher rates of vitreous relapse.Nearly one in seven eyes with retinoblastoma treated with primary chemotherapy may develop vitreous relapse. The administration of diode laser hyperthermia appears to increase this risk. Despite additional therapy a number of these eyes succumb to enucleation.

Dislocation of the lens nucleus into the vitreous cavity is one of the most severe complications in cataract surgery.1 ,2 Incidence of nucleus drop into the vitreous cavity for phacoemulsification surgery varies between 0.3% and 1.1% depending on the surgeon's experience.1–3 Retained nuclear material in the vitreous cavity can lead to severe complications like severe inflammation, intraocular pressure increase, cystoid macular oedema and retinal detachment.1 ,2 Risk factors for dropped nuclear fragments include: inexperienced surgeon, advanced age, undilated pupil, increased axial length, posterior polar cataract, hollow orbit, pseudoexfoliation, previous trauma and previous vitrectomy surgery.3 Early recognition of posterior capsular rupture (PCR) and zonular disruptions with prevention of collapse of the anterior chamber (AC) may prevent extension of the tear, forward movement of the vitreous, and displacement of the lens posteriorly. Signs of PCR include instantaneous deepening of AC, difficulty in holding nuclear fragments with phacoemulsification tip, descent of the nucleus away from the phacoemulsification tip and momentary pupillary dilatation.4 In case of a PCR without the posterior dislocation of nuclear fragments, and without prolapse of the vitreous into the AC, the nuclear fragments can be removed by phacoemulsification, or by conversion to a conventional extracapsular technique, after injecting a viscoelastic substance behind the nuclear material.4 When vitreous is present at the AC, continued phacoemulsification can exert traction on the vitreous base, increasing the risk of retinal detachment. Under such circumstances, removal of the residual lens material should follow an initial anterior vitrectomy. If there is danger of posterior dislocation of lens fragments, a second instrument may be placed behind the fragment(s) to prevent intravitreal migration. Zonular disruption, due to trauma or pseudoexfoliation, may cause total lens dislocation with associated lens cortex and capsule. In such cases, there is no capsular support for …

AIM To evaluate frequency and risk factors of retinal redetachment after removal of intraocular silicone oil tamponade. METHODS The study included 225 patients who consecutively underwent intraocular silicone oil removal at a mean interval of 10 months after pars plana vitrectomy had been performed by one of two surgeons. Mean follow up time was 17.37 (SD 14.40) months (range 3.02–67.42 months). RESULTS In 57 of 225 (25.3%) patients, the retina detached after removal of silicone oil. Risk factors for retinal redetachment were the following: number of previously unsuccessful retinal detachment surgeries (p=0.0008); surgeon (p=0.007); visual acuity before silicone oil removal (p=0.009); incomplete removal of vitreous base (p=0.01); absence of an encircling band in eyes with proliferate vitreoretinopathy in which an inferior retinotomy had not been performed (p=0.01); and indication for pars plana vitrectomy. Rate of retinal redetachment was statistically (p>0.05) independent of the technique of silicone oil removal and duration of silicone oil endotamponade. CONCLUSION Retinal redetachment after removal of silicone oil endotamponade can occur in approximately a fourth of patients, depending on the criteria to use and to remove silicone oil. Risk factors for recurrent detachment included the following: number of previously unsuccessful retinal detachment surgeries, surgeon, preoperative visual acuity, incomplete removal of the vitreous base, absence of an encircling band, and reason for pars plana vitrectomy. The rate of retinal redetachment is independent of the technique of silicone oil removal and duration of silicone oil endotamponade, with a minimal duration of silicone oil tamponade of about 3 months in the present study.

AIMS—To investigate the ultrastructure of the vitreoretinal interface following plasmin induced posterior vitreous detachment. METHODS—Plasmin (1 or 2 U/0.1 ml) was injected into the vitreous cavity of 24 eyes of freshly slaughtered pigs. The 24 fellow eyes received calcium-free and magnesium-free PBS and served as a control. After incubation at 37°C for 30 and 60 minutes, the globes were placed in fixative and hemisected. Specimens for light, scanning, and transmission electron microscopy were obtained from the posterior pole, the equator, and the vitreous base using a corneal trephine. RESULTS—All plasmin treated eyes showed posterior vitreous detachment. However, the inner limiting membrane (ILM) was covered by remnants of cortical vitreous at the posterior pole and at the equator. There was a direct correlation between the concentration and exposure times of plasmin and the degree of vitreoretinal separation. Eyes exposed to 1 U plasmin for 30 minutes had a dense network of residual collagen fibrils while those exposed to 1 U plasmin for 60 minutes had only sparse collagen fibrils covering the ILM. Eyes treated with 2 U plasmin for 60 minutes had a smooth retinal surface, consistent with a bare ILM. At the vitreous base there was no vitreoretinal separation. In all control eyes the vitreous cortex was completely attached to the retina. There was no evidence of retinal damage in any plasmin treated eye. CONCLUSION—Plasmin induces a cleavage between the vitreous cortex and the ILM without morphological changes to the retina. In contrast with previous reports, plasmin produces a smooth retinal surface and additional surgery is not required in this experimental setting. The degree of vitreoretinal separation depends on the concentration and length of exposure to plasmin.

Purpose To describe a technique of vitreous base visualisation through trans-scleral illumination using a standard 25-gauge light probe. Methods All vitrectomies are performed using 25-gauge+ instruments and valved trocars. A non-contact viewing system is used to visualise the retina. After core vitrectomy and the necessary additional procedures, triamcinolone acetonide (Kenacort) is injected in the vitreous cavity. Then, the standard 25-gauge light pipe is covered with a sleeve obtained from a 20-gauge venflon cannula. The light brightness is increased to 100%, and the light probe used to indent the sclera and trans-illuminate the vitreous base. The vitreous cutter is activated between the crystals of triamcinolone acetonide and the retinal surface. Complete vitreous base shaving is carried out for 360°. Results Iatrogenic peripheral retinal tears, as a result of vitreous shaving, occurred in 4.1% of cases with this technique. Conclusions This method represents a valid and low-cost option to achieve accurate vitreous base shaving.

The pathology of pars plana incisions of four patients is described: three with light microscopy and one with light and electron microscopy. Two eyes were removed because of choroidal melanoma, immediately and 8 days after vitrectomy and transvitreous retinal biopsy. Considerable disruption of tissues surrounding the pars plana incisions was observed. Vitreous was incarcerated in the wounds, which healed with granulation tissue. One eye was examined 4 months after vitrectomy for diabetic retinopathy and a failed pars plana filtering operation. It contained fibrovascular ingrowth from all the incisions, infiltrating the vitreous base with granulation tissue and causing vitreous haemorrhage and retinal detachment. One eye was removed 1 year after vitrectomy for anterior hyaloidal fibrovascular proliferation and early phthisis. The wound had fibrous ingrowth histologically and evidence of active fibroplasia.