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Vitrectomy
Kinds of Vitrectomy Selected Abstracts1231: How to identify retinal tears?ACTA OPHTHALMOLOGICA, Issue 2010JP BERROD Purpose Locating the retinal tear(s) in rhegmatogenous retinal detachment witout PVR is the first step of a successful treatment. The purpose of the course is to present the different techniques and rules to examine the retina in order to detect and locate all the tears. Methods We emphasised the 3 Lincoff's rules that permit concentration of the efforts to a small area of the periphery to identify the breaks. More than one break is present in 50% of eyes. Hence, there is a need to inspect the rest of the fundus including areas of attached retina. Results In the evaluation, one needs to stress the importance of good binocular indirect ophthalmoscopy with scleral depression or direct ophthalmocopy with slitlamp and 3 mirror contact lens. Vitrectomy can be indicated in certain cases of failure to detect breaks. In the presence of severe PVR the surgery would involve thorough cleaning of the entire retina, hence it may not be so important to identify all breaks preoperatively. Conclusion A minimal rate of postoperative failure for rhegmatogenous retinal detachment can only be achieved if a maximal preoperative search for the retinal breaks has been performed. [source] 1233: How to choose the best surgical procedure?ACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose Dealing to the localization and sealing retinal breaks, the surgical success rate for the cure of rhegmatogenous retinal detachment greatly changed with the introduction of scleral buckling (SB), intraocular gas injection, and pars plana vitrectomy (PPV). Methods In localized cases, pneumatic retinopexy and scleral buckling surgery (SB) remains the most popular surgical methods. Complicated cases with PVR grade B or C, giant tears, or macular holes are most commonly treated with primary pars plana vitrectomy. A large group of rhegmatogenous RDs with medium severity that comprise about 30% of all primary rhegmatogenous RDs in the Scleral Buckling versus Primary Vitrectomy in Rhegmatogenous Retinal Detachment recruitment study, were treated by SB and PPV. Advances in vitrectomy instrumentation and wideangle imaging systems have increased the popularity of PPV. Results The decision by the surgeon to use scleral buckling rather than PPV depends on a number of factors, including the lens status, size and location of breaks, patient compliance, and individual experience. Initial PPV may be successful for phakic patients. However, the SPR study shows a benefit of SB in phakic eyes with respect to BCVA improvement. Although no difference in BCVA was demonstrated in the pseudophakic trial, PPV was recommend for pseudophakic RD based on a better anatomical outcome. Conclusion There was a significant trend towards more frequently employing primary PPV (with or without SB) for the management of primary RRD. A significant improvement in the primary success rates for RD, were shown for all retinal surgical modalities applied for the treatment of rhegmatogenous retinal detachment. [source] 3121: Oxygen and treatment of ocular ischemic diseasesACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose In ischemia, reduced blood flow results in hypoxia. Hypoxic cells make hypoxia inducible factor (HIF), which controls many of the adaptive responses of tissue to ischemia. This includes vasodilatation, production of vascular endothelial factor (VEGF) with neovascularization and leakage, and finally apoptosis and tissue atrophy. Methods If hypoxia is improved this will reduce the production of VEGF and thereby reduce new vessel formation on one hand and vascular leakage and edeam formation on the other. Several methods are available to improve retinal hypoxia, including laser treatment, vitrectomy, vasodilatory drugs such as carbonic anhydrase inhibitors in addition to breathing oxygen. These treatment methods have been studied by many research groups with invasive polarographic electrodes and optical probes as well as noninvasive oxymetry in human patients and animal subjects. Results We will review experimental and clinical studies, which confirm that oxygen tension of the retina is increased following 1. retinal laser treatment 2. Vitrectomy 3. carbonic anhydrase inhibitors Conclusion Oxygen is the natural control of VEGF. VEGF levels in the retina and other ocular tissues are affected by oxygen levels and ischeimc diseases are currently treated with methods that affect oxygen and consequently VEGF. The addition of anti VEGF drugs to oxygen directed treatment such as laser and vitrectomy further influences the oxygen-HIF-VEGF-neovascularization/edema axis in ischemic retinopathies. [source] 3416: Surgical therapy of macular edemaACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose Persistent macular oedema (ME) is the main cause of poor visual outcome during the evolution of retinal ischemic microangiopathies and traction related macular distortion. Among multiples treatment approaches, vitreoretinal surgery is applied with the goal to achieve the release of a traction related component of macular oedema . Methods Vitrectomy with peeling of the posterior hyaloid, epiretinal membranes, vitreoretinal tractions and/or internal limiting membrane removal, were studied in numerous nonrandomized cases series. Results Pars plana vitrectomy has been shown to reduce macular oedema with significant change in best corrected visual acuity, in epiretinal membranes, vitreoretinal traction syndrome and ischemic microangiopathies related macular thickening central, hemiretinal, branch retinal vein occlusion and diabetic macular edema). Evidence to date does not support any therapeutic benefit from radial optic neurotomy and arteriovenous crossing sheathotomy for BRVO and CRVO related macular oedema. Conclusion In the era of intravitreal injection of steroids and anti VEGF substances, vitrectomy seems to have a beneficial effect in traction related, selected pathologies associated to chronic macular edema. [source] 2414: Laser and vitrectomyACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose Modern vitreous surgery involves a variety of treatment options in addition to vitrectomy itself, such as photocoagulation, anti-VEGF drugs, intravitreal steroids and release of vitreoretinal traction. A full understanding of these treatment modalities allows sensible combination of treatment options. Methods Vitrectomy reduces the risk of retinal neovascularization, while increasing the risk of iris neovascularization, reduces macular edema and stimulates cataract formation. These clinical consequences may be understood with the help of classical laws of physics and physiology. The laws of Fick, Stokes-Einstein and Hagen-Poiseuille state that molecular transport by diffusion or convection is inversely related to the viscosity of the medium. When the vitreous gel is replaced with less viscous saline, the transport of all molecules, including oxygen and cytokines, is facilitated. Oxygen transport to ischemic retinal areas is improved, as is clearance of VEGF and other cytokines from these areas, thus reducing edema and neovascularization. At the same time, oxygen is transported faster down a concentration gradient from the anterior to the posterior segment, while VEGF moves in the opposite direction, making the anterior segment less oxygenated and with more VEGF, stimulating iris neovascularization. Results Retinal photocoagulation has also repeatedly been shown to improve retinal oxygenation. Oxygen naturally reduces VEGF production and improves retinal hemodynamics. The VEGF-lowering effect of photocoagulation and vitrectomy can be augmented with anti-VEGF drugs and the permeability effect of VEGF reduced with corticosteroids Conclusion Vitrectomy and laser retinal treatment both improve oxygenation of the ischemic retina, reduce VEGF formation and thereby reduce neovascularisation and edema. [source] Vitrectomy may prevent the occurrence of diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 4 2010Audrey Navarro Abstract. Purpose:, This study aimed to demonstrate that vitrectomy may prevent the occurrence of diabetic macular oedema (DMO). Methods:, Three patients with diabetes type 1 underwent vitrectomy in one eye to treat complications of proliferative diabetic retinopathy. Results:, During follow-up, all patients suffered unilateral macular oedema in the non-vitrectomized eye as a result of general metabolic changes. In two of these patients, the DMO resolved with management of the underlying medical condition. Conclusions:, These case reports suggest the vitreous may play a role in the occurrence of DMO associated with general risk factors. Further studies are needed to increase understanding of the mechanisms involved in the development and progression of DMO. [source] Sulfur hexafluoride (SF6) versus perfluoropropane (C3F8) gas tamponade for macular hole surgeryACTA OPHTHALMOLOGICA, Issue 2009M STEFANIOTOU Purpose In Macular Hole surgery gas tamponade is hypothesized to enhance macular hole closure after removal of tangential force. Sulfur hexafluoride (SF6) was described in the initial report of Macular Hole surgery (MHS). Long lasting gas (such as C3F8) may offer more extensive tamponade . To compare outcomes of Macular Hole Surgery using SF6 gas versus C3F8 gas for idiopathic macular hole repair. Methods A consecutive group of patients undergoing MHS with SF6 group A (24 eyes of 24 patients) and a consecutive comparison group B with S3F8 was used (19 eyes of 19 patients). All patients had PP Vitrectomy, ILM peeling, using Kenacort or Blue and two different gases for internal tamponade. Results The macular hole closure rate was similar in both groups. Conclusion Macular Hole surgery using SF6 gas yields similar results as with C3F8 gas and may be a good option. [source] Is there still a place for vitrectomy in the treatment of macular edema due to venous occlusion ?ACTA OPHTHALMOLOGICA, Issue 2009CJ POURNARAS Purpose Persistent macular edema (ME) is the main cause of poor visual outcome in either non-ischemic BRVO or CRVO. Among multiples treatment approaches, vitreoretinal surgery with the goal to achieve the recanalisation of the occluded vessels and/or the resolution of ME, were proposed. Methods Vitrectomy with peeling of the posterior hyaloid and/or the internal limiting membrane,asociated to intravitreal (IVT) triamcinolone , neurotomy, sheathotomy, intravascular rtPA injection were studied in numerous nonrandomized cases series. Results Pars plana vitrectomy has been shown to reduce macular oedema and restore the normal foveal contour without significant change in best corrected visual acuity. In contrast, visual improvement occurs after vitrectomy for vitreous haemorrhage, epiretinal membrane formation and retinal detachment complicating BRVO. Evidence to date does not support any therapeutic benefit from radial optic neurotomy, optic nerve decompression, arteriovenous crossing sheathotomy or intravascular rtPA. Vitrectomy combined with IVT triamcinolone, induces a ME decrease rapidly and durably, without any improvement in visual acuity. Conclusion Vitrectomy with IVT triamcinolne seems to have a more durable effect than IVT triamcinolone alone.Vitrectomy, A-V sheathotomy combined with intravenous t-PA may offer benefits in BRVO. Despite uncertainty and open questions, surgical interventions are likely to be a therapeutic option for RVO in the future. Randomized and controlled studies are needed to confirm these results and to compare them to the natural course of the disease. [source] Primary vitrectomy in retinal detachment: is scleral buckling still indicated?ACTA OPHTHALMOLOGICA, Issue 2009CJ POURNARAS Purpose The surgical management of rhegmatogenous retinal detachment has evolved due to introduction of primary pars plana vitrectomy (PPV). The choice of primary vitrectomy has grown over recent years even for managment of simple retinal detachment. Methods Review of reports on primary vitrectomy treatment for rhegmatogenous uncomplicated retinal detachment. Evaluation of optimal indications of vitreectomy for specific types of retinal detachments. Results Comparaison of primary vitrectomy with scleral buckling had failed to demonstrate advantage of this method regarding anatomical and functional results. Vitrectomy avoids some of the complications associated with scleral buckling, such as diplopia, choroidal detachment, perforation of the sclera, abnormalities in the eyelid, but it carries higher risks of several other complications,including cataract formation in phakic eyes, glaucoma and other problems with tamponade, and new retinal breaks. Data from case series and randomized studies suggest that primary detachments in phakic eyes may be treated successfully with scleral buckling or vitrectomy, whereas vitrectomy appears to be preferable for corresponding detachments in pseudophakic eyes. Conclusion The choice of primary PPV in new uncomplicated retinal detachment remains to the surgeon's discretion and skills due to lack of controlled randomized trials covering the large spectrum of the retinal detachment pathology. [source] Micro Incisional Vitrectomy (MIVS): a new device for trocar insertionACTA OPHTHALMOLOGICA, Issue 2008S RIZZO Purpose Despite its clinical advantages, MIVS poses significant challenges in performing airtight incisions especially dealing with 23-gauge system. Aim of this paper was to assess the feasibility of performing 23-g MIVS using an injector system for trocar insertion. Methods 60 consecutive eyes of 56 patients underwent 23-g pp vitrectomy and gas endotamponade for the treatment of Regmatogenous Retinal detachment and Diabetic Prolipherative Retinopathy by the same surgeon (SD). 30 eyes were operated on with standard one-step 23-g and 30 using a prototype of injector holding the same 23-g trocar cannula system. The trocar squeezed into the plunger of the injector. The device had a metallic terminal oriented with a fix angle, allowing the insertion in the settled direction, able to fix the globe and displace the conjunctiva at the same time.Main outcome measure were sclerotomies airtightness, surgical time and complications. Results In the 30 eyes operated with the 23-g ones step system 9 sclerotomies were sutured, in 5 refilling was required. Mean surgical time were 54 minutes. In the 30 eyes operated with the new device, the inserter was easy to apply in all cases and was useful especially in the nasal quadrant. Also dealing with sunken eyes the inclination of the system 5-10° tangential to the sclera was easily achieved. No suture was placed, refilling was needed in 3 cases. Mean surgical time was 45 minutes. No complications due to these device were highlighted. Conclusion The new injector was safe and effective. The device facilitates the insertion manoeuvre allowing easier and quicker trocar positioning helping the airtight wound construction. MIVS success lie in the surgeon's skill but also in the development of the technology and instrumentations. [source] The therapeutic effects of retinal laser treatment and vitrectomy.ACTA OPHTHALMOLOGICA, Issue 5 2001A theory based on oxygen, vascular physiology ABSTRACT. The physiologic mechanism of photocoagulation can been seen in the following steps. The physical light energy is absorbed in the melanin of the retinal pigment epithelium. The adjacent photoreceptors are destroyed and are replaced by a glial scar and the oxygen consumption of the outer retina is reduced. Oxygen that normally diffuses from the choriocapillaris into the retina can now diffuse through the laser scars in the photoreceptor layer without being consumed in the mitochondria of the photoreceptors. This oxygen flux reaches the inner retina to relieve inner retinal hypoxia and raise the oxygen tension. As a result, the retinal arteries constrict and the bloodflow decreases. Hypoxia relief reduces production of growth factors such as VEGF and neovascularization is reduced or stopped. Vasoconstriction increases arteriolar resistance, decreases hydrostatic pressure in capillaries and venules and reduces edema formation according to Starling's law. Vitrectomy also improves retinal oxygenation by allowing oxygen and other nutrients to be transported in water currents in the vitreous cavity from well oxygenated to ischemic areas of the retina. Vitrectomy and retinal photocoagulation both improve retinal oxygenation and both reduce diabetic macular edema and retinal neovascularization. [source] Vitrectomy without postoperative posturing for idiopathic macular holesCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2007Adrian Rubinstein MRCSEd Abstract Purpose:, To determine the success of vitrectomy with ILM peeling and C3F8 tamponade for macular holes without the need for postoperative face-down posturing. Methods:, Twenty-four eyes of 24 consecutive patients undergoing pars plana vitrectomy with indocyanine green-assisted ILM peeling and C3F8 tamponade without prone posturing were included in the study. All patients had follow up on 1 day, 2 weeks and 3 months postoperatively. Biomicroscopy and optical coherence tomography were used to assess macular hole closure at 3 months postoperatively. Snellen visual acuity was compared pre- and postoperatively. Results:, Of the 24 eyes recruited, two (8%) had stage II, 17 (71%) had stage III and five (21%) had stage IV macular holes. Nineteen (79%) eyes were phakic and five (21%) eyes were pseudophakic at the time of surgery. The macular holes had been present for an average of 7.5 months (range 3,18 months). At 3-month follow up, 22/24 (91.6%) holes were closed. Both of the two holes that failed to close were stage IV macular holes. Preoperative visual acuity ranged from 6/18 to 6/60 (mean 6/36). Postoperative visual acuity ranged from 6/9 to 6/60 (mean 6/18). Eighteen eyes had improvement of visual acuity of at least one line on the Snellen chart, six eyes had no improvement. No eyes had worse vision postoperatively. Conclusion:, Macular hole surgery without face-down posturing provides anatomical and functional results comparable to those with prone posturing. Combined phacovitrectomy is not essential to avoid prone posturing. [source] Computer-assisted training system for pars plana vitrectomyACTA OPHTHALMOLOGICA, Issue 6 2003Jost B. Jonas Abstract. Purpose:,To evaluate whether microsurgical steps in vitreoretinal surgery can be taught by a computer-assisted training system. Methods:,This prospective, randomized experimental study included 14 ophthalmic residents and medical students who were completely inexperienced in microsurgery. They were randomized into two groups. The study group underwent training programmes in a computer-assisted training system for simulation of pars plana vitrectomy. The control group did not participate in any in vitro training. In the second phase of the study, participants of both groups performed a pars plana vitrectomy in three pig eyes, which included picking a metallic foreign body from the retinal surface. Results:,The amount of retinal detachment and the number of retinal defects at the end of the vitrectomies were smaller, the time needed to remove the foreign body was shorter, the number of retinal lesions associated with the foreign body removal was lower, and the mark given was better in the trained study group than in the untrained group. The relatively small number of study participants did not allow the differences between the study and control groups to reach the 5% level of error probability. Conclusions:,In an animal model, training by a computer-based medical work station for simulation of pars plana vitrectomy showed better outcome measures for trained study participants compared with untrained study participants. Future studies may show whether further refinements of such training programmes will result in statistically significantly better results in surgical outcome parameters. [source] Increased levels of monokine induced by interferon-, (Mig) in the vitreous of patients with diabetic retinopathyDIABETIC MEDICINE, Issue 7 2008Y. Wakabayashi Abstract Aim To determine the intravitreous concentration of monokine induced by interferon-, (Mig) in patients with diabetic retinopathy (DR) and the relation between Mig and vascular endothelial growth factor (VEGF). Research design and methods Vitreous samples were obtained at the time of vitrectomy from 41 eyes of 38 DR patients (30 with active DR and 11 with inactive DR) and from 15 eyes of 15 non-diabetic patients who had macular disease (control subjects). Human Mig and VEGF were quantified using a FACS Caliber® flow cytometer. Results The vitreous concentration of Mig was increased significantly in patients with both active and inactive DR [148.0 (31.6,997.2; median range) and 82.3 (25.7,347.7) pg/ml, respectively] compared with control subjects [21.0 (5.2,74.3) pg/ml; P < 0.0001 and P < 0.001, respectively]. In DR patients, a significant (P < 0.01) correlation was observed between vitreous concentrations of Mig and VEGF. Conclusion Our results suggest that Mig may play an important role in the pathogenesis of DR and works in consort with VEGF in the progression of pathological angiogenesis in DR. [source] Equine recurrent uveitis: A clinical manifestation of leptospirosisEQUINE VETERINARY EDUCATION, Issue 10 2009L. Frellstedt Summary Leptospirosis is a zoonosis of worldwide distribution affecting domestic animals, wildlife and man. The bacterial disease is caused by pathogenic Leptospira spp., which are transmitted from reservoir hosts to accidental hosts. Horses are accidental hosts and can become susceptible to leptospiral infections. Widespread exposure to leptospires exists and is significantly more common than clinical disease. Leptospirosis can have different clinical manifestations including abortion, still birth, systemic disease with hepatic or renal dysfunction, and equine recurrent uveitis (ERU). ERU is the most frequently encountered clinical manifestation and this article will focus on the review of leptospira-associated ERU. Equine recurrent uveitis is the most common cause of vision impairment and blindness in horses. The pathogenesis of leptospira-associated ERU involves direct bacterial effects and immune-mediated responses. Clinical signs vary between the acute and chronic phases of the disease and progress over time. The diagnosis of leptospira-associated ERU can be difficult and usually requires a combination of diagnostic tests. Medical and surgical treatments have been described with varying outcomes. The prognosis for sight is usually poor, although core vitrectomy may improve the outcome. Avoidance of leptospiral exposure of horses is the only reliable prevention of leptospira-associated disease. [source] Atropine-induced lens extrusion in an open eye surgeryPEDIATRIC ANESTHESIA, Issue 1 2006ANJOLIE CHHABRA MD Summary A 2-month-old male baby undergoing penetrating keratoplasty (PKP) under general anesthesia developed bradycardia and a decrease in heart rate to 53 b·min,1 when stay sutures were taken through the superior and inferior rectii. A bolus of 0.1 mg intravenous atropine resulted in tachycardia of up to 180,220 b·min,1, which persisted for 35 min. After corneal trephination was performed the eyeball seemed to pulsate with the heartbeat. Spontaneous extrusion of the lens and vitreous occurred, which necessitated a lensectomy and vitrectomy in addition to PKP. The role of atropine in corneal transplant surgery is discussed here. [source] Reducing the incidence of early postoperative vitreous haemorrhage by preoperative intravitreal bevacizumab in vitrectomy for diabetic tractional retinal detachmentACTA OPHTHALMOLOGICA, Issue 6 2010Ling Yeung Acta Ophthalmol. 2010: 88: 635,640 Abstract. Purpose:, This study aimed to evaluate whether preoperative intravitreal injection of bevacizumab reduces early postoperative vitreous haemorrhage (VH) in vitrectomy for diabetic tractional retinal detachment. Methods:, We conducted a retrospective chart review of a consecutive, interventional case series. This included 29 eyes (27 patients) in the bevacizumab group and 40 eyes (37 patients) in the non-bevacizumab group. For statistical analysis, each patient was assigned to one of four groups according to the haemostatic modalities used (group 1, none; group 2, only long-acting gas; group 3, only preoperative intravitreal bevacizumab; group 4, both long-acting gas and preoperative intravitreal bevacizumab). The primary outcome measure was the incidence of early postoperative VH. The secondary outcome measure was visual acuity (VA) at 1 month. Results:, The incidence of early postoperative VH was highest in group 1 (63%), followed by group 2 (21%), group 3 (20%) and group 4 (5%). Group 3 showed the best visual recovery in the first month. All eyes in group 3 reached VA , 1/100 at 1 month after the operation, compared with 44%, 29% and 42% in groups 1, 2 and 4, respectively. Conclusions:, Preoperative intravitreal injection of bevacizumab may be useful for reducing early postoperative VH in vitrectomy for diabetic tractional retinal detachment. Eyes receiving preoperative intravitreal bevacizumab without the use of long-acting gas achieved the best visual recovery at 1 month after the operation. [source] Increase of vascular endothelial growth factor and interleukin-6 in the aqueous humour of patients with macular oedema and central retinal vein occlusionACTA OPHTHALMOLOGICA, Issue 6 2010Hidetaka Noma Acta Ophthalmol. 2010: 88: 646,651 Abstract. Purpose:, This study aimed to investigate whether vascular endothelial growth factor (VEGF) or interleukin-6 (IL-6) influence macular oedema in patients with central retinal vein occlusion (CRVO). Methods:, Sixteen consecutive patients with unilateral CRVO and macular oedema were studied, along with eight age- and sex-matched patients without ischaemic ocular disease. Retinal ischaemia was evaluated from capillary non-perfusion on fluorescein angiography. Macular oedema was examined by optical coherence tomography. Aqueous humour (AH) samples were obtained during combined pars plana vitrectomy and cataract surgery, and were examined by enzyme-linked immunosorbent assay. Results:, Aqueous levels of VEGF and IL-6 were significantly elevated in patients compared with controls (p = 0.0142 and p < 0.0001, respectively). Aqueous levels of both molecules were significantly higher in patients with ischaemia than in those without ischaemia (p = 0.0026 and p = 0.0487, respectively). Furthermore, AH levels of VEGF and IL-6 were correlated with the severity of macular oedema (, = 0.7265, p = 0.0049, , = 0.5324, and p = 0.0392, respectively). Conclusions:, Both VEGF and IL-6 were elevated in the AH of patients with macular oedema and ischaemic CRVO, suggesting that these molecules may be related to the increase in vascular permeability in such patients. [source] Retinal sensitivity and fixation changes 1 year after triamcinolone acetonide assisted internal limiting membrane peeling for macular hole surgery , a MP-1 microperimetric studyACTA OPHTHALMOLOGICA, Issue 6 2010Hakan Ozdemir Acta Ophthalmol. 2010: 88: e222,e227 Abstract. Purpose:, To evaluate microperimetric changes 1 year after macular hole surgery with triamcinolone acetonide assisted internal limiting membrane (ILM) peeling. Methods:, Twenty-two eyes of 22 patients with stage 3 and 4 idiopathic macular holes of <6 months' duration underwent vitrectomy with triamcinolone acetonide assisted ILM peeling. Best corrected visual acuity (BCVA) (logarithm of the minimum angle of resolution), and central retinal sensitivity were documented before and 1, 3, 6, and 12 months after surgery. Macular sensitivity (mean sensitivity in decibels -dB), and stability and location of fixation (preferred retinal locus) were determined using MP-1 microperimetry (Nidek). The MP-1 microperimetry sensitivity map was overlaid onto infrared images recorded on a Heidelberg scanning laser ophthalmoscope using dedicated MP-1 software to evaluate the fixation location before surgery. Anatomical success was evaluated with optical coherence tomography (OCT). Optical coherence tomography scans were recorded on an OCT 3000 scanner. Results:, Anatomical success was achieved in all 22 eyes. All patients completed 1 year follow-up. No recurrence of macular hole was seen in any patients in the follow-up period. The mean BCVA improved from 0.75 ± 0.2 before surgery to 0.31 ± 0.1 logMAR at the last visit (p < 0.001). Mean sensitivity improved from 3.7 ± 0.6 to 5.3 ± 1.0 dB at the last visit (p < 0.001). Before surgery, the preferred retinal locus was located on the margin of the hole in all, in 18 eyes on its upper part and in four eyes to the side or on its lower part. Preoperatively, 12 eyes were stable and 10 were relatively unstable, but 12 month after surgery, fixation stability had improved, and 20 eyes were stable and two were relatively unstable. Conclusions:, MP-1 microperimetry sensitivity map overlaid onto an infrared image using dedicated MP-1 software can be used successfully to evaluate fixation location in patients with a macular hole before surgery. With microperimetry findings, we can also measure functional macular changes more precisely than using BCVA alone after macular hole surgery. Our results also showed that retinal sensitivity and fixation properties were improved after vitrectomy with triamcinolone acetonide assisted ILM peeling in patients with idiopathic macular hole. [source] 1233: How to choose the best surgical procedure?ACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose Dealing to the localization and sealing retinal breaks, the surgical success rate for the cure of rhegmatogenous retinal detachment greatly changed with the introduction of scleral buckling (SB), intraocular gas injection, and pars plana vitrectomy (PPV). Methods In localized cases, pneumatic retinopexy and scleral buckling surgery (SB) remains the most popular surgical methods. Complicated cases with PVR grade B or C, giant tears, or macular holes are most commonly treated with primary pars plana vitrectomy. A large group of rhegmatogenous RDs with medium severity that comprise about 30% of all primary rhegmatogenous RDs in the Scleral Buckling versus Primary Vitrectomy in Rhegmatogenous Retinal Detachment recruitment study, were treated by SB and PPV. Advances in vitrectomy instrumentation and wideangle imaging systems have increased the popularity of PPV. Results The decision by the surgeon to use scleral buckling rather than PPV depends on a number of factors, including the lens status, size and location of breaks, patient compliance, and individual experience. Initial PPV may be successful for phakic patients. However, the SPR study shows a benefit of SB in phakic eyes with respect to BCVA improvement. Although no difference in BCVA was demonstrated in the pseudophakic trial, PPV was recommend for pseudophakic RD based on a better anatomical outcome. Conclusion There was a significant trend towards more frequently employing primary PPV (with or without SB) for the management of primary RRD. A significant improvement in the primary success rates for RD, were shown for all retinal surgical modalities applied for the treatment of rhegmatogenous retinal detachment. [source] 4235: Vitreoretinal considerations in OOKPACTA OPHTHALMOLOGICA, Issue 2010E HUGHES Purpose To present the difficulties of managing vitreoretinal complications in patients with OOKP and open a discussion about future strategies to prevent and deal with these problems. Methods Retrospective review of cases. Results Vitreo-retinal complications occurred in 14 of 54 patients receiving OOKP surgery. These included vitreous hemorrhage (4 patients), rhegmatogenous retinal detachment (3 patients), endophthalmitis with retinal detachment (5 patients), endophthalmitis without retinal detachment (1 patient) and intraoperative choroidal hemorrhage (1 patient). Most cases of endophthalmitis presented late and may result from lamina resorption, leak and hypotony. The prognosis of retinal detachment in an eye with OOKP was poor with successful repair in 1 of 3 cases not related to endophthalmitis and 0 of 5 cases with endophthalmitis. Overall, pars plana vitrectomy was performed on 10 occasions (8 patients), of which 2 were endoscopic and 2 utilised a temporary keratoprosthesis. Conclusion There is a relatively high rate of posterior segment problems in OOKP patients and their management is challenging both in assessment (limited view and ultrasound amenability) and surgical approach. Surgical outcomes were poor for these complications. Other concepts in management, including endoscopic vitrectomy at stage I surgery should be considered, which will be discussed. [source] 3315: Transconjunctival sutureless 20GACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose To evaluate a trocar system that allows the use of the regular 20-gauge vitrectomy instruments for a transconjunctival sutureless surgery for the treatment of various surgically treated vitreo-retinal pathologies. Methods The 20-gauge trocar system uses a 10° self-sealing tunneled incision made with trocars introduced with a inserter blade of 0.9 mm diameter. Incisions are radially made at 3.5 mm from the limbus and tunnels are made limbus-parallel. Evaluation of the surgical procedure, sclerotomies closure by OCT, anatomical and visual outcomes in various vitreoretinal pathologies treated in current vitreoretinal practice. Results Postoperative patient comfort and less eye inflammation are provided by the sutureless technique, allthough small conjunctival hemorrhage caused by the grasping forceps used to hold the eye during the insertion of the trocars may occur. The 20-gauge trocar system using 10° self-sealing tunneled incision remains very stable in the eye even during peripheral vitrectomy with indentation and they also decrease the surgical induced trauma at the entry sites. The use of nonflexible instruments, the same as in 20-gauge conventional vitrectomy, provides easy access to the entire periphery.thus the system can be used in almost all vitreoretinal surgeries. It allows the use of phragmatome and is easy to work even with 5,000 centistokes silicone oil. Conclusion In the era of sutureless surgeries, the 20-gauge trocar system is a safe, comfortable, convinient with current instrumentation and less expensive alternative to 25- and 23-gauge vitrectomy. [source] 3121: Oxygen and treatment of ocular ischemic diseasesACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose In ischemia, reduced blood flow results in hypoxia. Hypoxic cells make hypoxia inducible factor (HIF), which controls many of the adaptive responses of tissue to ischemia. This includes vasodilatation, production of vascular endothelial factor (VEGF) with neovascularization and leakage, and finally apoptosis and tissue atrophy. Methods If hypoxia is improved this will reduce the production of VEGF and thereby reduce new vessel formation on one hand and vascular leakage and edeam formation on the other. Several methods are available to improve retinal hypoxia, including laser treatment, vitrectomy, vasodilatory drugs such as carbonic anhydrase inhibitors in addition to breathing oxygen. These treatment methods have been studied by many research groups with invasive polarographic electrodes and optical probes as well as noninvasive oxymetry in human patients and animal subjects. Results We will review experimental and clinical studies, which confirm that oxygen tension of the retina is increased following 1. retinal laser treatment 2. Vitrectomy 3. carbonic anhydrase inhibitors Conclusion Oxygen is the natural control of VEGF. VEGF levels in the retina and other ocular tissues are affected by oxygen levels and ischeimc diseases are currently treated with methods that affect oxygen and consequently VEGF. The addition of anti VEGF drugs to oxygen directed treatment such as laser and vitrectomy further influences the oxygen-HIF-VEGF-neovascularization/edema axis in ischemic retinopathies. [source] 3415: Treatment of postoperative macular edemaACTA OPHTHALMOLOGICA, Issue 2010I PETROPOULOS Purpose Cystoid macular edema (CME) is a frequent complication of a number of interventions in ophthalmology, such as cataract surgery (Irvine-Gass syndrome), laser procedures, and trabeculectomy. The purpose of this talk is to present the latest bibliographic data regarding the appropriate treatment of postoperative CME. Methods A review of the existing literature concerning the treatment of postoperative CME is performed. Characteristic personal cases are presented. Results In more than two-thirds of the cases, postoperative CME resolves spontaneously within weeks or months. Prophylactic topical treatment with indomethacin or flurbiprofen seems to reduce the frequency of clinical and angiographic CME, but its beneficial effect on final visual acuity is not established. Curative therapy includes topical corticosteroids; topical non-steroidal anti-inflammatory drugs (e.g. ketorolac); oral acetazolamide; sub-Tenon or intravitreal injection of triamcinolone acetonide; intravitreal injection of anti-VEGF drugs; and pars plana vitrectomy. The indications, role, and efficacy of each of the above treatment modalities are discussed, based on the latest bibliographic data. Conclusion Most cases of postoperative CME are mild and resolve spontaneously. In refractory cases, sub-Tenon or intravitreal injection of triamcinolone acetonide can be effective, but the risk of ocular hypertony is high. Intravitreal injection of anti-VEGF drugs offers promising results, yet large-scale randomized studies are necessary to validate their utility. Finally, pars plana vitrectomy is the treatment of choice when vitreomacular traction and/or epiretinal membrane is present. [source] 3416: Surgical therapy of macular edemaACTA OPHTHALMOLOGICA, Issue 2010CJ POURNARAS Purpose Persistent macular oedema (ME) is the main cause of poor visual outcome during the evolution of retinal ischemic microangiopathies and traction related macular distortion. Among multiples treatment approaches, vitreoretinal surgery is applied with the goal to achieve the release of a traction related component of macular oedema . Methods Vitrectomy with peeling of the posterior hyaloid, epiretinal membranes, vitreoretinal tractions and/or internal limiting membrane removal, were studied in numerous nonrandomized cases series. Results Pars plana vitrectomy has been shown to reduce macular oedema with significant change in best corrected visual acuity, in epiretinal membranes, vitreoretinal traction syndrome and ischemic microangiopathies related macular thickening central, hemiretinal, branch retinal vein occlusion and diabetic macular edema). Evidence to date does not support any therapeutic benefit from radial optic neurotomy and arteriovenous crossing sheathotomy for BRVO and CRVO related macular oedema. Conclusion In the era of intravitreal injection of steroids and anti VEGF substances, vitrectomy seems to have a beneficial effect in traction related, selected pathologies associated to chronic macular edema. [source] 2414: Laser and vitrectomyACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose Modern vitreous surgery involves a variety of treatment options in addition to vitrectomy itself, such as photocoagulation, anti-VEGF drugs, intravitreal steroids and release of vitreoretinal traction. A full understanding of these treatment modalities allows sensible combination of treatment options. Methods Vitrectomy reduces the risk of retinal neovascularization, while increasing the risk of iris neovascularization, reduces macular edema and stimulates cataract formation. These clinical consequences may be understood with the help of classical laws of physics and physiology. The laws of Fick, Stokes-Einstein and Hagen-Poiseuille state that molecular transport by diffusion or convection is inversely related to the viscosity of the medium. When the vitreous gel is replaced with less viscous saline, the transport of all molecules, including oxygen and cytokines, is facilitated. Oxygen transport to ischemic retinal areas is improved, as is clearance of VEGF and other cytokines from these areas, thus reducing edema and neovascularization. At the same time, oxygen is transported faster down a concentration gradient from the anterior to the posterior segment, while VEGF moves in the opposite direction, making the anterior segment less oxygenated and with more VEGF, stimulating iris neovascularization. Results Retinal photocoagulation has also repeatedly been shown to improve retinal oxygenation. Oxygen naturally reduces VEGF production and improves retinal hemodynamics. The VEGF-lowering effect of photocoagulation and vitrectomy can be augmented with anti-VEGF drugs and the permeability effect of VEGF reduced with corticosteroids Conclusion Vitrectomy and laser retinal treatment both improve oxygenation of the ischemic retina, reduce VEGF formation and thereby reduce neovascularisation and edema. [source] 2122: Role of prophylactic topical nepafenac in prevention of post pars-plana vitrectomy macular edemaACTA OPHTHALMOLOGICA, Issue 2010S MISHRA Purpose To evaluate the effects of topical nepafenac in patients undergoing pars plana vitrectomy (PPV) with special emphasis on its role in post PPV macular edema. Methods 108 patients undergoing PPV were randomized to receive either topical nepafenac 0.3% (53 eyes) or placebo (55 eyes) from 3 days preoperatively till 4 weeks postoperative in addition to topical steroids and antibiotics in this single center investigator masked study. Optical coherence tomography (OCT) was done at week 2,4,6 and 8 post operatively. Results Patients taking nepafenac and those taking placebo had mean postoperative day 1 pain scores of 0.25 and 1.08 (P=0.03) and mean inflammation grades of 0.49 and 1.34 (P=0.002) respectively. Although centre subfield macular thickness (CSMT) was lesser in nepafenac group as compared to placebo group (260.56 µm Vs 270.70 µm at week 2, 228.44 µm Vs 236.21 µm at week 4, 215.02 µm Vs 218.74 µm at week 6 and 205.35 µm Vs 205.17 µm at week 8 respectively), the difference did not reach statistically significant levels (P>0.05) at any visit. There was also, no statistically significant improvement in best corrected visual acuity between the nepafenac group and the placebo group at any postoperative visit. Conclusion Although addition of 0.3% nepafenac decreased postoperative pain and inflammation, it did not reduce incidence of macular edema in patients undergoing PPV. Topical nepafenac was well tolerated and safe but did not improve visual recovery in this set of patients. [source] 4333: How does scleral buckling affect the anterior segment of the eye?ACTA OPHTHALMOLOGICA, Issue 2010FJ ASCASO Purpose To describe the modifications produced in the anterior segment of the eye after placing an encircling scleral buckling (SB) in terms of corneal morphology, biomechanics and intraocular pressure. Methods A prospective study of 15 eyes with rhegmatogenous retinal detachment who underwent pars plana vitrectomy combined with a scleral buckle (PPV/SB), and 12 eyes with vitreous hemorrhage treated with PPV alone. We measured preoperatively and 1-month after surgery the corneal biomechanical properties using the Ocular Response Analyzer (ORA), including corneal hysteresis (CH), corneal resistance factor (CRF), intraocular pressure (IOPg), and corneal compensated IOP (IOPcc). Moreover, we defined the corneal morphology by 4 parameters provided by the topographer Orbscan IIz: mean corneal power (dioptres), standard deviation, thinnest point (µm), and anterior chamber depth (ACD) (mm). Results Mean CH values were significantly diminished following PPV/SB (p=0.003). We found no significant changes in CRF. IOPg and IOPcc mean values were significantly increased only in the PPV/SB group (p=0.019 and p=0.010, respectively) but not in PPV group (p=0.715 and p=0.273, respectively). In PPV/SB group, IOPcc mean values were significantly higher than IOPg before (p=0.001) and after surgery (p=0.003), but not in the other group. None of the morphological parameters were modified after surgery in any of the two study groups (p>0.05) Conclusion Anterior segment morphology was not modified after placing a SB. Corneal biomechanical properties showed a reduction in CH, probably due to a vascular constriction and reduction of the eye compliance. PPV might be considered a less invasive approach for the repair of noncomplex retinal detachments than PPV/SB. [source] Vitrectomy may prevent the occurrence of diabetic macular oedemaACTA OPHTHALMOLOGICA, Issue 4 2010Audrey Navarro Abstract. Purpose:, This study aimed to demonstrate that vitrectomy may prevent the occurrence of diabetic macular oedema (DMO). Methods:, Three patients with diabetes type 1 underwent vitrectomy in one eye to treat complications of proliferative diabetic retinopathy. Results:, During follow-up, all patients suffered unilateral macular oedema in the non-vitrectomized eye as a result of general metabolic changes. In two of these patients, the DMO resolved with management of the underlying medical condition. Conclusions:, These case reports suggest the vitreous may play a role in the occurrence of DMO associated with general risk factors. Further studies are needed to increase understanding of the mechanisms involved in the development and progression of DMO. [source] Involvement of intraocular structures in disseminated histoplasmosisACTA OPHTHALMOLOGICA, Issue 4 2010Marianne Ala-Kauhaluoma Abstract. Purpose:, To describe ocular involvement and response to treatment in a patient with human immunodeficiency virus (HIV) infection with severe progressive disseminated histoplasmosis (PDH). Methods:, We report a 35-year-old HIV-infected patient seen in our clinics over a period of 4 years. During antiretroviral treatment (ART), the HIV load became undetectable at 3 months; however, CD4 T-cell count increased slowly and rose to 100 cells/,l. Histoplasma capsulatum was cultured from skin pustules, cerebrospinal fluid (CF) and aqueous humour. Results:, The patient developed central nervous system (CNS) involvement 2 months and panuveitis in both eyes 4 months after the initiation of ART. With intravenous liposomal amphotericin B followed by oral voricanozole, the chorioretinal lesions of the right eye (RE) became inactivated and magnetic resonance imaging (MRI) lesions of CNS disappeared. Relapse of the inflammation in the anterior segment of the left eye (LE) resulted in a total closure of the chamber angle and severe glaucoma. Despite medical therapy, two cyclophotocoagulations, total vitrectomy and repeated intravitreal amphotericin B injections, LE became blind. Histoplasma capsulatum was cultured from the aqueous humour after antifungal therapy of 16 months' duration. Conclusion:, PDH with intraocular and CNS manifestations was probably manifested by an enhanced immune response against a previous subclinical disseminated infection. It seems difficult to eradicate H. capsulatum from the anterior segment of the eye in an immunocompromised patient. [source] | ||||||||||