637 resultados para Aberración intraocular
Resumo:
The role played by autophagy after ischemia/reperfusion (I/R) in the retina remains unknown. Our study investigated whether ischemic injury in the retina, which causes an energy crisis, would induce autophagy. Retinal ischemia was induced by elevation of the intraocular pressure and modulation of autophagic markers was analyzed at the protein levels in an early and late phase of recovery. Following retinal ischemia an increase in LC3BII was first observed in the early phase of recovery but did not stay until the late phase of recovery. Post-ischemic induction of autophagy by intravitreal rapamycin administration did not provide protection against the lesion induced by the ischemic stress. On the contrary, an increase in the number of apoptotic cells was observed following I/R in the rapamycin treated retinas.
Resumo:
Implantation of a phakic iris claw intraocular lens is a common, effective and safe procedure to correct high myopia, hyperopia and astigmatism [2]. Due to the nature of its fixation on the iris using claws, chronic irritation and inflammation have remained a major concern with the Artisan® lens since its market introduction in 1998. Following iris claw implantation, monitoring of postoperative inflammation is mandatory [4][7]. Usually, signs of inflammation can be detected in the anterior chamber during the early postoperative period. We present here the first case of late-onset inflammation after implantation of an iris claw lens triggered by an iris varix. The iris varix is a rare benign iris vascular abnormality, with a low prevalence as a solitary primary lesion in the general population and little is known about its clinical characteristics [1][5][6]. This report shows that an iris varix could be a cause of a late onset and chronic inflammation after phakic Artisan® lens implantation.
New formulation of vasoactive intestinal peptide using liposomes in hyaluronic acid gel for uveitis.
Resumo:
We evaluated the benefits of a novel formulation of vasoactive intestinal peptide (VIP) based on the incorporation of VIP-loaded rhodamine-conjugated liposomes (VIP-Rh-Lip) within hyaluronic acid (HA) gel (Gel-VIP-Rh-Lip) for the treatment of endotoxin-induced uveitis (EIU) in comparison with VIP-Rh-Lip alone. In vitro release study and rheological analysis showed that interactions between HA chains and liposomes resulted in increased viscosity and reinforced elasticity of the gel. In vivo a single intravitreal injection of Gel-VIP-Rh-Lip was performed in rats 7 days prior to uveitis induction by subcutaneous lipopolysaccharide injection. The maximal ocular inflammation occurs within 16-24 h in controls (VIP-Rh-Lip, unloaded-Rh-Lip). Whereas intraocular injection of VIP-Rh-Lip had no effect on EIU severity compared with controls, Gel-VIP-Rh-Lip reduced significantly the clinical score and number of inflammatory cells infiltrating the eye. The fate of liposomes, VIP and HA in the eyes, regional and inguinal lymph nodes and spleen was analyzed by immunostaining and fluorescence microscopy. Retention of liposomes by HA gel was observed in vitro and in vivo. Inflammation severity seemed to impact on system stability resulting in the delayed release of VIP. Thus, HA gel containing VIP-Rh-Lip is an efficient strategy to obtain a sustained delivery of VIP in ocular and lymph node tissues.
Resumo:
BACKGROUND: The aim of this communication is to describe an unusual and serious complication of retrobulbar anaesthesia for cataract surgery. HISTORY AND SIGNS: A 78-year-old female was referred for visual loss (light perception) 24 hours after apparently uneventful cataract surgery with retrobulbar anaesthesia in her left eye. Fundus examination revealed multiple arterial emboli and a localised retinal detachment. MRI revealed a retrobulbar hypersignal of the optic nerve associated with perineuritis. The cardiovascular examination was normal. We assumed this condition resulted from injection of the anaesthetic mixture into the optic nerve. THERAPY AND OUTCOME: In order to improve retinal circulation and oxygenation, the intraocular pressure was maximally lowered and anticalcic therapy administered, expecting optimal arterial dilatation. Methylprednisolone (1 g/day 3 days i. v., then rapidly tapered) was also added. The retina slowly reattached but visual acuity remained unchanged. CONCLUSIONS: Retrobulbar anaesthesia is routinely used for ocular surgery. Serious complications may still happen, however. This case adds to the previously reported spectrum of complications from retrobulbar anaesthesia.
Resumo:
PURPOSE: To evaluate the long-term success rate and complications of nonpenetrating deep sclerectomy with collagen implant in open-angle glaucoma. PATIENTS AND METHODS: Clinical, prospective, monocentric, nonrandomized, unmasked study on 105 patients with medically uncontrolled glaucoma. A standard procedure deep sclerectomy with collagen implant was performed. Complete examinations were performed before surgery and postoperatively at 1 and 7 days; 1, 2, 3, 6, 9, and 12 months and then every 6 months during the 10 following years. RESULTS: The mean follow-up was 101.5+/-43.1 (3 to 144) months [mean+/-SD, (range)]. The preoperative intraocular pressure (IOP) was 26.8+/-7.7 (14 to 52) mm Hg and the best-corrected visual acuity 0.71+/-0.33 (0.02 to 1.5). Ten years after surgery IOP was 12.2+/-4.7 (6 to 20) mm Hg and best-corrected visual acuity 0.63+/-0.34 (0.01 to 1.2) (number of remaining patients=52). The mean number of medications per patient went from 2.3+/-0.7 (1 to 4) down to 1.3+/-1.1 (0 to 3). An IOP <or=21 mm Hg without medication was achieved in 47.7% patients and in 89% with or without treatment. One major complication was reported. Goniopuncture was performed in 61 eyes (59.8%), 5-fluorouracil treatment given to 25 patients postoperatively and included needling (n=5). CONCLUSIONS: On the basis of a 10-year follow-up deep sclerectomy with collagen implant demonstrated its efficacy in controlling IOP with few postoperative complications.
Resumo:
ABSTRACT : Background : The aim of this study was to evaluate the midterm biocompatibility of a new x-shaped implant made of zirconium in an animal model of glaucoma surgery. Methods : Preoperatively, ultrasound biomicroscopy (UBM), intraocular pressure (IOP) and outflow facility (OF) data were acquired. Upon surgery, one eye was chosen randomly to receive an implant, while the other received none. Ten rabbits went through a 1-, 2-, 3-, 4- and 6-month follow-up. [OP was measured regularly, UBM performed at 1, 3 and 6 months after surgery. At the end of the follow-up, OF was again measured. Histology sections were analyzed. Results : For both groups IOP control was satisfactory, while OF initially increased at month 1 to resume preoperative values thereafter. Eyes with implants had larger filtration blebs which decreased faster than in eyes without the implant. Drainage vessel density, inflammatory cell number and fibrosis were higher in tissues near the implant. Conclusions : The zirconium implant initially promoted the positive effects of the surgery (IOP control, OF increase). Nevertheless, after several months, foreign body reactions and fibrosis had occurred on some implants that restrained the early benefit of such a procedure. Modifications of the zirconium implant geometry could enhance the overall success rate.
Resumo:
Purpose: To compare the performance Glaucoma Quality of Life-15 (GQL-15) Questionnaire, intraocular pressure measurement (IOP Goldmann tonometry) and a measure of visual field loss using Moorfields Motion Displacement Test (MDT) in detecting glaucomatous eyes from a self referred population. Methods: The GQL-15 has been suggested to correlate with visual disability and psychophysical measures of visual function in glaucoma patients. The Moorfields MDT is a multi location perimetry test with 32 white line stimuli presented on a grey background on a standard laptop computer. Each stimulus is displaced between computer frames to give the illusion of "apparent motion". Participants (N=312, 90% older than 45 years; 20.5% family history of glaucoma) self referred to an advertised World Glaucoma Day (March 2009) Jules Gonin Eye Hospital, Lausanne Switzerland. Participants underwent a clinical exam (IOP, slit lamp, angle and disc examination by a general ophthalmologist), 90% completed a GQL-15 questionnaire and over 50% completed a MDT test in both eyes. Those who were classified as abnormal on one or more of the following (IOP >21 mmHg/ GQL-15 score >20/ MDT score >2/ clinical exam) underwent a follow up clinical examination by a glaucoma specialist including imaging and threshold perimetry. After the second examination subjects were classified as "healthy"(H), "glaucoma suspect" (GS) (ocular hypertension and/or suspicious disc, angle closure with SD) or "glaucomatous" (G). Results: One hundred and ten subjects completed all 4 initial examinations; of these 69 were referred to complete the 2nd examination and were classified as; 8 G, 24 GS, and 37 H. MDT detected 7/8 G, and 7/24 GS, with false referral rate of 3.8%. IOP detected 2/8 G and 8/24 GS, with false referral rate of 8.9%. GQL-15 detected 4/8 G, 16/24 GS with a false referral rate of 42%. Conclusions: In this sample of participants attending a self referral glaucoma detection event, the MDT performed significantly better than the GQL-15 and IOP in discriminating glaucomatous patients from healthy subjects. Further studies are required to assess the potential of the MDT as a glaucoma screening tool.
Resumo:
PURPOSE: To describe methods and outcomes of excisional revision of a filtering bleb (bleb revision) using free conjunctival autologous graft either for bleb repair or for bleb reduction after trabeculectomy and deep sclerectomy with an implant. METHODS: Retrospective medical records were reviewed for a consecutive non-comparative case series comprising patients who underwent excisional revision of a filtering bleb between May 1998-January 2001. Excisional revision using free conjunctival autologous graft (bleb revision) was performed either for bleb repair, to treat early and late leaks and hypotony with maculopathy, or for bleb reduction, to improve ocular pain, discomfort, burning, foreign body sensation, tearing, and fluctuations of visual acuity. The revision consisted of bleb excision and free conjunctival autologous graft. The bleb histopathology was analyzed in patients who underwent bleb repair. RESULTS: Sixteen patients were included in the study, consisting of nine patients who had a trabeculectomy and seven patients who had a deep sclerectomy with an implant. Bleb revision was necessary in 14 patients due to leaking filtering bleb (bleb repair), and in 2 patients due to bleb dysesthesia (bleb reduction). After a follow-up of 15.1 +/- 8.4 months, the mean intraocular pressure (IOP) rose from 7.8 +/- 6.3 mm Hg to 14.3 +/- 6.5 mm Hg, and the visual acuity from 0.4 +/- 0.3 to 0.7 +/- 0.3, with a P value of 0.008 and 0.03, respectively. The complete success rate at 32 months, according to the Kaplan-Meier survival curve, was 38.3%, and the qualified success rate was 83.3%. Four patients (25%) required additional suturing for persistent bleb leak. To control IOP, antiglaucoma medical therapy was needed for six patients (37.5%) and repeated glaucoma surgery was needed for one patient. CONCLUSION: Free conjunctival autologous graft is a safe and successful procedure for bleb repair and bleb reduction. However, patients should be aware of the postoperative possibility of requiring medical or surgical intervention for IOP control after revision.
Resumo:
PURPOSE: To investigate the ability of fibroblast growth factor (FGF) 2-saporin to prevent lens regrowth in the rabbit. METHODS: Chemically conjugated and genetically fused FGF2-saporin (made in Escherichia coli) were used. Extracapsular extraction of the lens was performed on the rabbit, and the cytotoxin either was injected directly into the capsule bag or was administered by FGF2-saporin-coated, heparin surface-modified (HSM) polymethylmethacrylate intraocular lenses. The potential of the conjugate was checked by slit lamp evaluation of capsular opacification and by measuring crystallin synthesis. Toxin diffusion and sites of toxin binding were assessed by immunohistochemistry. Possible toxicity was determined by histologic analysis of ocular tissues. RESULTS: FGF2-saporin effectively inhibited lens regrowth when it was injected directly into the capsular bag. However, high concentration of the toxin induced transient corneal edema and loss of pigment in the iris. Intraocular lenses coated with FGF2-saporin reduced lens regrowth and crystallin synthesis without any detectable clinical side effect. After implantation, FGF2-saporin was shown to have bound to the capsules and, to a lesser extent, to the iris; no histologic damage was found on ocular tissues as a result of implantation of drug-loaded HSM intraocular lenses. CONCLUSIONS: Chemically conjugated (FGF2-SAP) and genetically fused FGF2-saporin (rFGF2-SAP) bound to HSM intraocular lenses can prevent lens regrowth in the rabbit.
Resumo:
Two cases of idiopathic sclerochoroidal calcification are reported with follow-up of two and ten years. In addition we have reviewed 102 cases of choroidal osteoma, including six misleading case reports which actually described idiopathic sclerochoroidal calcification and not choroidal osteoma. Clinical manifestation and the angiographic features of idiopathic sclerochoroidal calcification are outlined. The differential diagnosis of intraocular deposition of calcium salts is discussed in detail.
Resumo:
Retinoblastoma is the most common eye cancer in children. Pilot studies of chemotherapy for intraocular retinoblastoma have been reported by several groups, using different combinations, dosages, schedules, and durations of carboplatin, etoposide, or teniposide, with or without vincristine, and with or without cyclosporine to counteract multidrug resistance. All studies of chemotherapy for intraocular retinoblastoma have included consolidation by focal therapy, with or without radiation. Chemotherapy alone reduces tumor size but does not cure retinoblastoma. Focal therapy, consisting of photocoagulation, thermotherapy, cryotherapy, or brachytherapy, is necessary to consolidate chemotherapy response.
Resumo:
PURPOSE: Ocular anatomy and radiation-associated toxicities provide unique challenges for external beam radiation therapy. For treatment planning, precise modeling of organs at risk and tumor volume are crucial. Development of a precise eye model and automatic adaptation of this model to patients' anatomy remain problematic because of organ shape variability. This work introduces the application of a 3-dimensional (3D) statistical shape model as a novel method for precise eye modeling for external beam radiation therapy of intraocular tumors. METHODS AND MATERIALS: Manual and automatic segmentations were compared for 17 patients, based on head computed tomography (CT) volume scans. A 3D statistical shape model of the cornea, lens, and sclera as well as of the optic disc position was developed. Furthermore, an active shape model was built to enable automatic fitting of the eye model to CT slice stacks. Cross-validation was performed based on leave-one-out tests for all training shapes by measuring dice coefficients and mean segmentation errors between automatic segmentation and manual segmentation by an expert. RESULTS: Cross-validation revealed a dice similarity of 95% ± 2% for the sclera and cornea and 91% ± 2% for the lens. Overall, mean segmentation error was found to be 0.3 ± 0.1 mm. Average segmentation time was 14 ± 2 s on a standard personal computer. CONCLUSIONS: Our results show that the solution presented outperforms state-of-the-art methods in terms of accuracy, reliability, and robustness. Moreover, the eye model shape as well as its variability is learned from a training set rather than by making shape assumptions (eg, as with the spherical or elliptical model). Therefore, the model appears to be capable of modeling nonspherically and nonelliptically shaped eyes.
Resumo:
Two cases of a benign form of optic disc edema after successful trabeculectomy are reported. In both patients, optic disc edema was noted 2 to 4 weeks after trabeculectomy. The edema occurred without loss of visual acuity or field. The absolute intraocular pressure and intracranial pressure were normal--that is, the edema was not a syndrome of hypotony or pseudotumor cerebri. However, both patients had intracranial pressure in the high-normal range. The decrease in intraocular pressure into the low normal range after trabeculectomy may have altered the intracranial pressure:intraocular pressure ratio at the lamina cribrosa enough to produce optic disc edema.
Resumo:
PURPOSE: To study the influence of retinal structural changes on oxygen saturation in retinitis pigmentosa (RP) patients. METHODS: Oximetry measurements were performed on 21 eyes of 11 RP patients and compared to 24 eyes of 12 controls. Retinal oxygen saturation was measured in all major retinal arterioles (A-SO₂) and venules (V-SO₂) with an oximetry unit of the retinal vessel analyser (IMEDOS Systems UG, Jena, Germany). Oximetry data were compared with morphological changes measured by Cirrus optical coherence tomography (OCT) (Carl Zeiss Meditec, Dublin, CA, USA, macular thickness protocol). RESULTS: In RP patients, the retinal A-SO₂ and V-SO₂ levels were higher at 99.3% (p = 0.001, anova based on mixed-effects model) and 66.8% (p < 0.001), respectively, and the difference between the two (A-V SO₂) was lower at 32.5% (p < 0.001), when compared to the control group (92.4%; 54.0%; 38.4%, respectively). With the RP group, the A-V SO₂ correlated positively, not only with central macular thickness, but also with retinal thickness, in zones 2 and 3 (p = 0.006, p = 0.007, p = 0.014). CONCLUSION: These data indicate that oxygen metabolism was altered in RP patients. Based on our preliminary results, retinal vessel saturation correlated with structural alterations in RP. This method could be valuable in monitoring disease progression and evaluating a potential therapeutic response.
Resumo:
Trilateral retinoblastoma (TRb) is a rare disease associating intraocular retinoblastoma with intracranial primitive neuroectodermal tumor. Treatment is difficult and prognosis is poor. This multicenter study evaluates clinical findings and MR imaging characteristics of associated intracranial tumors in Rb patients. Clinical data of 17 patients (16 TRb and 1 quadrilateral Rb patients) included time intervals between Rb and TRb diagnosis and presence of baseline brain-imaging (BBI). Two reviewers reviewed all images individually and one reviewer per center evaluated their images. Consensus was reached during a joint scoring session. Studies were reviewed for tumor location, size and imaging characteristics (signal intensity (SI) on T1- and T2-weighted images, enhancement pattern and cystic appearance). Of 18 intracranial tumors, 78 % were located in the pineal gland and 22 % suprasellar. All tumors showed well-defined borders with mostly heterogenous enhancement (72 %) and isointense SI on T1- (78 %) and T2-weighted images (72 %) compared to gray matter. The majority of pineal TRbs showed a cystic component (57 %). TRb detected synchronously with the intraocular tumors on BBI (n = 7) were significantly smaller (P = 0.02), and mainly asymptomatic than TRb detected later on (n = 10). Overall, 5-year-survival of TRb patients detected on BBI was 67 % (95 % CI 29-100 %) compared to 11 % (95 % CI 0-32 %) for the group with delayed diagnosis. TRb mainly develops in the pineal gland and frequently presents with a cystic appearance that could be misinterpreted as benign pineal cysts. Routine BBI in all newly diagnosed Rb patients can detect TRb at a subclinical stage.