Holz, Eric R.
2009-01-01
Purpose: To study the refractive outcomes of 3-port lens-sparing vitrectomy (LSV) for subtotal retinal detachments due to retinopathy of prematurity (ROP). Lens-sparing vitrectomy may provide superior refractive outcomes by limiting induced myopia of prematurity. Methods: This is a retrospective, consecutive, nonrandomized, comparative (paired eye) study. Entrance criteria were previous complete ablative laser for threshold ROP in both eyes, followed by LSV in one eye for stage 4A traction retinal detachment. Both eyes then maintained complete retinal attachment. Main outcome variables were cycloplegic refraction, keratometry, and biometric values for axial length, lens thickness, and anterior chamber depth. Results: Nine patients met inclusion criteria. Lens-sparing vitrectomy eyes were significantly less myopic than control eyes (−6.78 D vs −10.33 D, P < .005). The reduction in myopia in LSV eyes was predominantly due to increased anterior chamber depth (3.81 mm ± 0.217 vs 2.96 mm ± 0.232, P < .005). There was a minor contribution from reduced corneal power in LSV eyes (43.89 D ± 0.253 vs 44.20 D ± 0.265, P < .005). There was a minor negative impact from increased lens thickness in LSV eyes (3.85 ± 0.32 mm vs 3.74 ± 0.31, P < .005). There was no significant difference in axial length or lens power between the LSV and control groups. Conclusions: The data demonstrate that infant eyes undergoing 3-port LSV for stage 4A ROP develop less myopia than fellow eyes treated with laser alone. The difference is due to posterior displacement of the lens-iris diaphragm with a smaller contribution from reduced corneal power. The reduction in myopia may improve functional outcomes following 3-port LSV for stage 4A ROP. PMID:20126504
Optimized feline vitrectomy technique for therapeutic stem cell delivery to the inner retina
Jayaram, Hari; Becker, Silke; Eastlake, Karen; Jones, Megan F; Charteris, David G; Limb, G Astrid
2014-01-01
Objective To describe an optimized surgical technique for feline vitrectomy which reduces bleeding and aids posterior gel clearance in order to facilitate stem cell delivery to the inner retina using cellular scaffolds. Procedures Three-port pars plana vitrectomies were performed in six-specific pathogen-free domestic cats using an optimized surgical technique to improve access and minimize severe intraoperative bleeding. Results The surgical procedure was successfully completed in all six animals. Lens sparing vitrectomy resulted in peripheral lens touch in one of three animals but without cataract formation. Transient bleeding from sclerotomies, which was readily controlled, was seen in two of the six animals. No cases of vitreous hemorrhage, severe postoperative inflammation, retinal detachment, or endophthalmitis were observed during postoperative follow-up. Conclusions Three-port pars plana vitrectomy can be performed successfully in the cat in a safe and controlled manner when the appropriate precautions are taken to minimize the risk of developing intraoperative hemorrhage. This technique may facilitate the use of feline models of inner retinal degeneration for the development of stem cell transplantation techniques using cellular scaffolds. PMID:24661435
Optimized feline vitrectomy technique for therapeutic stem cell delivery to the inner retina.
Jayaram, Hari; Becker, Silke; Eastlake, Karen; Jones, Megan F; Charteris, David G; Limb, G Astrid
2014-07-01
To describe an optimized surgical technique for feline vitrectomy which reduces bleeding and aids posterior gel clearance in order to facilitate stem cell delivery to the inner retina using cellular scaffolds. Three-port pars plana vitrectomies were performed in six-specific pathogen-free domestic cats using an optimized surgical technique to improve access and minimize severe intraoperative bleeding. The surgical procedure was successfully completed in all six animals. Lens sparing vitrectomy resulted in peripheral lens touch in one of three animals but without cataract formation. Transient bleeding from sclerotomies, which was readily controlled, was seen in two of the six animals. No cases of vitreous hemorrhage, severe postoperative inflammation, retinal detachment, or endophthalmitis were observed during postoperative follow-up. Three-port pars plana vitrectomy can be performed successfully in the cat in a safe and controlled manner when the appropriate precautions are taken to minimize the risk of developing intraoperative hemorrhage. This technique may facilitate the use of feline models of inner retinal degeneration for the development of stem cell transplantation techniques using cellular scaffolds. © 2014 The Authors Veterinary Ophthalmology published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Ophthalmologists.
Spatula scaffold: An iris-sparing technique for lensectomy.
Narang, Priya; Agarwal, Amar
2017-12-01
Lensectomy with vitrectomy is often performed for crystalline lenticular subluxation. We report a new technique and a practical approach that involves the placement of a spatula beneath the iris tissue that facilitates retroiridial removal of subluxated lens and acts as a scaffold by protecting the iris tissue from being accidentally trapped into the vitrectomy cutter port. Our technique facilitates management of the lens and vitreous without any trauma to the iris and secondarily obviates the need to perform an iris repair procedure that may arise due to iatrogenic reasons.
Thomas, Benjamin J; Yonekawa, Yoshihiro; Trese, Michael T
2016-01-01
To describe the long-term anatomical and visual outcomes of a patient with retinopathy of prematurity characterized by a prominent retinal fold adherent to the posterior lens capsule, treated by lens-sparing vitrectomy with surgical transection of the retrolental membrane. A premature infant was born at a gestational age of 25 weeks and birthweight of 636 g. She developed threshold retinopathy of prematurity bilaterally and was subsequently treated with laser ablative therapy. The left eye responded favorably, with regression of neovascularization; however, the right eye progressed to Stage 4A with a prominent retinal fold adherent to the posterior lens capsule. The patient underwent lens-sparing vitrectomy with dissection of the retrolental membrane at postmenstrual age of 44 weeks. At 15-year follow-up, the patient has maintained a best-corrected visual acuity of 20/60 and, of note, demonstrated complete resolution of the previous retinal fold. Surgical treatment for retinopathy of prematurity was considerably advanced by the introduction of lens-sparing vitrectomy techniques; however, cases developing retrolental membranes often persisted with poor visual outcomes, and lensectomy is conventionally performed. However, in select cases of Stage 4A retinopathy of prematurity, careful transection of retrolental membranes during lens-sparing vitrectomy using the appropriate technique may provide very good anatomical and visual outcomes.
Iwase, Takeshi; Yamamoto, Kentaro; Yanagida, Kosei; Kobayashi, Misato; Ra, Eimei; Murotani, Kenta; Terasaki, Hiroko
2016-08-01
The aim of this study was to compare changes in refraction following lens-sparing vitrectomy between patients with rhegmatogenous retinal detachment (RRD) and epiretinal membrane (ERM) and to investigate factors associated with the change in refraction.We reviewed medical records of 49 eyes of 49 patients with RRD (53.6 ± 7.8 years, mean ± standard deviation) and 24 eyes of 24 patients with ERM (50.9 ± 15.7 years) who underwent lens-sparing vitrectomy. Spherical equivalent refractive power was evaluated before and up to 18 months after surgery. The relationship between the change in refraction and several parameters was evaluated.A significant progressive myopic shift in refractive power was observed after vitrectomy in operated RRD and ERM eyes (P < 0.001, P = 0.016, respectively), with no significant difference in fellow eyes. The refraction values observed at ≥3 and ≥12 months following vitrectomy were significantly different as compared with those observed at baseline in the RRD group (P < 0.001) and the ERM group (P < 0.05), respectively. The change in refraction between the RRD and ERM groups was significant (P = 0.030). The multiple linear regression analysis showed that only age was significantly correlated with the change in refraction in RRD (P = 0.018) and ERM (P < 0.001) groups. The change in refraction was significantly and positively correlated with age in RRD (r = -0.461, P = 0.001) and ERM (r = -0.687, P < 0.001) groups. Following lens-sparing vitrectomy, cataract surgery was performed on 30 eyes after 0.89 ± 0.26 years in the RRD group and on 10 eyes after 1.11 ± 0.14 years in the ERM group; there was a significant difference in time to cataract surgery between the groups (P = 0.007). Kaplan-Meier survival analysis demonstrated that there was a significant difference in the rate of cataract surgeries between the RRD and ERM groups (P = 0.022).Following lens-sparing vitrectomy for RRD and ERM, a progressive myopic shift in refraction owing to nuclear sclerosis was observed. Core vitrectomy itself would cause a myopic shift of refraction. The only risk factor associated with cataract progression following lens-sparing vitrectomy is age for both types of patients.
Iwase, Takeshi; Yamamoto, Kentaro; Yanagida, Kosei; Kobayashi, Misato; Ra, Eimei; Murotani, Kenta; Terasaki, Hiroko
2016-01-01
Abstract The aim of this study was to compare changes in refraction following lens-sparing vitrectomy between patients with rhegmatogenous retinal detachment (RRD) and epiretinal membrane (ERM) and to investigate factors associated with the change in refraction. We reviewed medical records of 49 eyes of 49 patients with RRD (53.6 ± 7.8 years, mean ± standard deviation) and 24 eyes of 24 patients with ERM (50.9 ± 15.7 years) who underwent lens-sparing vitrectomy. Spherical equivalent refractive power was evaluated before and up to 18 months after surgery. The relationship between the change in refraction and several parameters was evaluated. A significant progressive myopic shift in refractive power was observed after vitrectomy in operated RRD and ERM eyes (P < 0.001, P = 0.016, respectively), with no significant difference in fellow eyes. The refraction values observed at ≥3 and ≥12 months following vitrectomy were significantly different as compared with those observed at baseline in the RRD group (P < 0.001) and the ERM group (P < 0.05), respectively. The change in refraction between the RRD and ERM groups was significant (P = 0.030). The multiple linear regression analysis showed that only age was significantly correlated with the change in refraction in RRD (P = 0.018) and ERM (P < 0.001) groups. The change in refraction was significantly and positively correlated with age in RRD (r = −0.461, P = 0.001) and ERM (r = −0.687, P < 0.001) groups. Following lens-sparing vitrectomy, cataract surgery was performed on 30 eyes after 0.89 ± 0.26 years in the RRD group and on 10 eyes after 1.11 ± 0.14 years in the ERM group; there was a significant difference in time to cataract surgery between the groups (P = 0.007). Kaplan–Meier survival analysis demonstrated that there was a significant difference in the rate of cataract surgeries between the RRD and ERM groups (P = 0.022). Following lens-sparing vitrectomy for RRD and ERM, a progressive myopic shift in refraction owing to nuclear sclerosis was observed. Core vitrectomy itself would cause a myopic shift of refraction. The only risk factor associated with cataract progression following lens-sparing vitrectomy is age for both types of patients. PMID:27512843
[Outcomes of surgical management of retinopathy of prematurity--an overview].
Kuprjanowicz, Leszek; Kubasik-Kładna, Katarzyna; Modrzejewska, Monika
2014-01-01
According to the guidelines by the ETROP (Early Treatment for Retinopathy of Prematurity) study group, laser therapy is the gold standard in the treatment of retinopathy of prematurity. However, progression of the disease is seen in 12% of eyes despite the treatment. Since there is no causal treatment, new therapies of retinopathy of prematurity, are continually sought, such as anti-VEGF agents, beta-blockers, or insulin-like growth factor gene therapy. In cases with concomitant retinal detachment, surgery is performed. The standard therapy for retinopathy of prematurity stages 4-5 involves pars plicata vitrectomy and lensectomy (stage 5), ab externo surgery (scleral buckling) and lens-sparing vitrectomy (some cases of stage 4). Classic vitrectomy with lensectomy is reserved only for cases with advanced retinal tractions, retina-lens apposition or for cases of intraoperative lens damage during the lens-sparing vitrectomy. The ab externo surgery does not eliminate vitreous tractions, but it stabilises the neovascular membrane activity (transforming it into a scar). The indication for this type of operation is stage 4 retinopathy of prematurity with peripheral proliferations, except for the posterior--aggressive form of retinopathy of prematurity. Many papers have been published on combined therapy involving vitrectomy and conservative treatment. In conclusion, optimal timing of surgical intervention is difficult to determine in stages 4 and 5, because the anatomical and functional outcomes in stage 5 are unfavourable. Both, ab externo surgery and vitrectomy tend to produce poor macular vision in eyes with advanced retinopathy of prematurity, therefore surgical intervention at stage 4 just before the local macular retinal detachment provides better anatomical and functional outcomes.
Ravani, Raghav; Chawla, Rohan; Azad, Shorya Vardhan; Gupta, Yogita; Kumar, Vinod; Kumar, Atul
2018-01-01
Purpose: The objective of this study is to describe the removal of retained intraocular foreign body (RIOFB) by bimanual pars plana vitrectomy through midline sclerotomy in phakic patients. Technique: Four eyes with RIOFB and clear lens underwent microincision vitrectomy surgery. A chandelier illumination was placed through one of the existing ports. The foreign body (FB) was localized by direct visualization (intravitreal) or indentation (pars plana), stabilized using an intraocular magnet/FB forceps introduced through a midline sclerotomy and freed of vitreous from all sides using a vitrectomy cutter through the other port bimanually, reoriented along their long axis and extracted through the midline sclerotomy. Results: All four FBs were removed successfully without slippage or damage to the clear lens. Conclusion: Chandelier illumination-assisted removal of FB through midline sclerotomy helps in easier localization, stabilization and removal, avoiding lens touch even in anteriorly located FBs such as at pars plana. PMID:29676316
Intravitreal Phacoemulsification Using Torsional Handpiece for Retained Lens Fragments.
Kumar, Vinod; Takkar, Brijesh
2016-01-01
To evaluate the results of intravitreal phacoemulsification with torsional hand piece in eyes with posteriorly dislocated lens fragments. In this prospective, interventional case series, 15 eyes with retained lens fragments following phacoemulsification were included. All patients underwent standard three-port pars plana vitrectomy and intravitreal phacoemulsification using sleeveless, torsional hand piece (OZiL™, Alcon's Infiniti Vision System). Patients were followed up for a minimum of six months to evaluate the visual outcomes and complications. The preoperative best-corrected visual acuity (BCVA) ranged from light perception to 0.3. No complications such as thermal burns of the scleral wound, retinal damage due to flying lens fragments, or difficult lens aspiration occurred during intravitreal phacoemulsification. Mean post-operative BCVA at the final follow-up was 0.5. Two eyes developed cystoid macular edema, which was managed medically. No retinal detachment was noted. Intravitreal phacoemulsification using torsional hand piece is a safe and effective alternative to conventional longitudinal phacofragmentation.
[Dry transconjunctival sutureless 25-gauge vitrectomy in the treatment of pediatric cataract].
You, Cai-yun; Xie, Li-xin
2009-08-01
Posterior capsule opacification is the most frequent complication of pediatric cataract surgery. To prevent posterior capsule opacification, primary phacoemulsification, posterior capsulotomy and anterior vitrectomy with intraocular lens implantation is the preferred method in the treatment of pediatric cataract. Anterior vitrectomy cutter, with 18-gauge, maximum frequency at 600/min and has simultaneous cutting, irrigation and aspiration functions, is associated with more complications and poor outcomes. In 20-gauge surgery, pars plana vitrectomy is performed with two-port sclerotomy. The irrigation increases movement of vitreous and 20-gauge sclerotomy needs suture for closing. In 25-gauge surgery, the vitreous cutter can be introduced into the vitreous cavity directly though conjunctiva and sclera. The stab incision is roughly half the size of 20-gauge cutter, therefore, the sclerotomy incision can be left unsutured. Surgery with dry transconjunctival sutureless 25-gauge vitrectomy may decrease the requirement for secondary membrane surgery and the risk for retinal detachment. The application of dry transconjunctival sutureless 25-gauge vitrectomy in the treatment of pediatric cataract is reviewed.
Intravitreal Phacoemulsification Using Torsional Handpiece for Retained Lens Fragments
Kumar, Vinod; Takkar, Brijesh
2016-01-01
Purpose: To evaluate the results of intravitreal phacoemulsification with torsional hand piece in eyes with posteriorly dislocated lens fragments. Methods: In this prospective, interventional case series, 15 eyes with retained lens fragments following phacoemulsification were included. All patients underwent standard three-port pars plana vitrectomy and intravitreal phacoemulsification using sleeveless, torsional hand piece (OZiL™, Alcon's Infiniti Vision System). Patients were followed up for a minimum of six months to evaluate the visual outcomes and complications. Results: The preoperative best-corrected visual acuity (BCVA) ranged from light perception to 0.3. No complications such as thermal burns of the scleral wound, retinal damage due to flying lens fragments, or difficult lens aspiration occurred during intravitreal phacoemulsification. Mean post-operative BCVA at the final follow-up was 0.5. Two eyes developed cystoid macular edema, which was managed medically. No retinal detachment was noted. Conclusion: Intravitreal phacoemulsification using torsional hand piece is a safe and effective alternative to conventional longitudinal phacofragmentation. PMID:27621783
Gadkari, Salil Sharad; Deshpande, Madan
2017-01-01
Purpose: We sought to document the difference in the vitreoretinal configuration of Stage 4 retinopathy of prematurity (ROP) in photocoagulated and treatment naive eyes undergoing vitrectomy and to correlate it with surgical complexity. Methods: Consecutive eyes posted for vitrectomy with Stage 4 ROP were documented preoperatively using a RetCam for the presence of peripheral traction (PT), presence of central traction just outside the arcades, and presence of traction extending to the lens. A note was made of the following intraoperative events: lensectomy, intraoperative bleeding, and iatrogenic breaks. Wilcoxon rank-sum test was used for analysis. Results: From a total of 46 eyes, 16 and 30 eyes were from the treated and treatment naive group, respectively. More eyes in the treated group had central (P < 0.0001) and lenticular traction (P = 0.022). More eyes in the untreated group had PT (P < 0.0001). A significant number of eyes without photocoagulation needed lensectomy (P = 0.042), and no difference in intraoperative bleeding (P = 0.94) was demonstrable. Iatrogenic retinotomy occurred in three eyes, all naive. Notably, age at surgery was more in the untreated group (P = 0.00008). Conclusion: Vasoproliferative activity in all retinopathies occurs at the junction of the ischemic and nonischemic retina. In the natural course of ROP, this takes place peripherally, at the ridge. In photocoagulated eyes, this junction is displaced posteriorly due to peripheral ablation. Treated eyes manifested with posterior proliferative changes and were more amenable to lens-sparing vitrectomy. Naive eyes were older when they underwent surgery to relieve PT with greater chances of lensectomy and iatrogenic breaks. PMID:28905829
Kweon, Eui Yong; Ahn, Min; Lee, Dong Wook; You, In Cheon; Kim, Min Jung; Cho, Nam Chun
2009-01-01
The purpose of this study is to report the features of operating microscope light-induced retinal phototoxic maculopathy after transscleral sutured posterior chamber intraocular lens (TSS PC-IOL) implantation. The charts of 118 patients who underwent TSS PC-IOL implantation surgery at Chonbuk National University Hospital (Jeonju, Korea) between March 1999 and February 2008 were retrospectively reviewed. Fourteen patients underwent combined 3-port pars plana vitrectomy and TSS PC-IOL implantation (vitrectomy group), and 104 patients underwent TSS PC-IOL implantation only (nonvitrectomy group). All surgeries were performed under the same coaxial illuminated microscope. All diagnoses were confirmed through careful fundus examination and fluorescein angiography (FA). Diagnoses of retinal phototoxic maculopathy were established in 10 (8.47%) of 118 TSS PC-IOL implantation cases. Phototoxic maculopathy occurred more frequently in the vitrectomy group than in the nonvitrectomy group (6/14 versus 4/104, respectively; P < 0.001, chi-square = 24.21). Affected patients reported decreased vision and were found to have coarse alterations of the retinal pigment epithelium (RPE). In 5 of the phototoxic maculopathy cases (50%), the visual acuity was 20/200 or worse. Operating microscope light-induced retinal phototoxic maculopathy can occur more frequently after TSS PC-IOL implantation than after casual cataract surgery, especially when TSS PC-IOL is combined with vitrectomy surgery. Surgeons should take precautions to prevent retinal phototoxicity after TSS PC-IOL implantation and vitrectomy.
Wu, Jian-Guo; Wei, Rui-Hua; Liu, Ai-Hua; Zhou, Xiao-Xu; Sun, Guo-Ling; Li, Xiao-Rong
2011-01-01
Background: The purpose of this prospective, interventional, comparative case series was to evaluate the efficiency and feasibility of a disposable sutureless silicone lens ring for corneal contact lens stabilization during combined 23-gauge vitrectomy and cataract surgery. Methods: We developed a ring consisting of a single silicone component with three footplates along the ring margin to fit cannulae for holding conventional contact lenses. Thirty eyes from 30 patients with cataract and vitreoretinal disease were included, and divided into two matched groups according to disease type and ring used. In Group A, we used a 23-gauge transconjunctival vitrectomy system and a disposable sutureless silicone lens ring (n = 15). In Group B, we used a 23-gauge transconjunctival vitrectomy system and a conventional metal lens ring (n = 15). The main outcome measures were: time required for vitrectomy preparation, rate of intraoperative corneal limbus bleeding, and limbus scar rate at the final follow-up visit. Results: Thirty cases were successfully completed. The average vitrectomy preparation time was less in Group A than in Group B (P < 0.01), and the average preparation time saved was 3.94 minutes. None of the Group A patients had intraoperative bleeding or postoperative scarring, whereas all 15 Group B cases had bleeding and five had scarring. There was a statistically significant difference between Group A and Group B for these complications (P ≤ 0.05). Conclusion: This report demonstrates the advantages of using a sutureless silicone ring during combined 23-gauge vitrectomy and cataract surgery. Using this method could allow extra time for the surgeon to pay more attention to complex vitreoretinal procedures. PMID:21760720
Wu, Jian-Guo; Wei, Rui-Hua; Liu, Ai-Hua; Zhou, Xiao-Xu; Sun, Guo-Ling; Li, Xiao-Rong
2011-01-01
The purpose of this prospective, interventional, comparative case series was to evaluate the efficiency and feasibility of a disposable sutureless silicone lens ring for corneal contact lens stabilization during combined 23-gauge vitrectomy and cataract surgery. We developed a ring consisting of a single silicone component with three footplates along the ring margin to fit cannulae for holding conventional contact lenses. Thirty eyes from 30 patients with cataract and vitreoretinal disease were included, and divided into two matched groups according to disease type and ring used. In Group A, we used a 23-gauge transconjunctival vitrectomy system and a disposable sutureless silicone lens ring (n = 15). In Group B, we used a 23-gauge transconjunctival vitrectomy system and a conventional metal lens ring (n = 15). The main outcome measures were: time required for vitrectomy preparation, rate of intraoperative corneal limbus bleeding, and limbus scar rate at the final follow-up visit. Thirty cases were successfully completed. The average vitrectomy preparation time was less in Group A than in Group B (P < 0.01), and the average preparation time saved was 3.94 minutes. None of the Group A patients had intraoperative bleeding or postoperative scarring, whereas all 15 Group B cases had bleeding and five had scarring. There was a statistically significant difference between Group A and Group B for these complications (P ≤ 0.05). This report demonstrates the advantages of using a sutureless silicone ring during combined 23-gauge vitrectomy and cataract surgery. Using this method could allow extra time for the surgeon to pay more attention to complex vitreoretinal procedures.
Hayashi, Ken; Ogawa, Soichiro; Manabe, Shin-Ichi; Hirata, Akira; Yoshimura, Koichi
2016-03-01
The aim of this study was to examine the recent status of intraocular lens (IOL) dislocation according to a classification system based on vertical dislocation position, as well as the surgical techniques and outcomes of IOL exchange surgery. The medical records of 230 eyes from 214 consecutive patients who experienced IOL dislocation and underwent exchange surgery between 2006 and 2014 were reviewed. Vertical dislocation sites observed preoperatively under operating microscopy were examined, along with the surgical techniques and outcomes of IOL exchange. Dislocation sites included (1) the anterior chamber (12.2 %), (2) pseudophakodonesis (19.1 %), (3) the anterior vitreous cavity (47.4 %), (4) trap door-like dislocation (dangling in the peripheral vitreous cavity; 16.1 %), and (5) the retinal surface (5.2 %). The IOL retained in the anterior segment was moved onto the iris by pulling it up through the limbal side ports with an anterior vitrectomy (67.8 %), or by pushing it up from the pars plana with an anterior vitrectomy (26.5 %), while the IOL dropped on the retina was lifting it up from the retina after pars plana vitrectomy (5.7 %). Mean uncorrected and distance-corrected visual acuity significantly improved postoperatively (p < 0.0001). Major complications included a marked elevation in intraocular pressure (7.8 %), pupillary capture (6.5 %), and vitreous hemorrhage (2.6 %). Based on the classification system, approximately 95 % of dislocated IOLs were retained in the anterior segment, and these IOLs were exchanged using an anterior approach through limbal incisions with an anterior vitrectomy. Visual acuity improved significantly, and serious complications were uncommon, probably because the IOL exchange techniques were standardized and simplified without pars plana vitrectomy.
Treatment of dystrophic calcification on a silicone intraocular lens with pars plana vitrectomy
Mehta, Nitish; Goldberg, Roger A; Shah, Chirag P
2014-01-01
Purpose Dense, vision-obscuring calcification on the posterior aspect of silicone intraocular lenses (IOLs) is often not amenable to neodymium:yttrium-aluminum-garnet capsulotomy, and, in prior reports, has required IOL exchange. We report the successful removal of dense calcium deposition on the posterior surface of a three-piece silicone lens using pars plana vitrectomy (PPV). Materials and methods A 23-gauge PPV was performed using the Stellaris® vitrectomy system. A light pipe was used to retroilluminate the IOL, and a dense fibrous tissue setting with a low cut-rate and high aspiration rate was able to clear the visual axis of the dystrophic calcification without damaging the IOL optic. Results Visual acuity improved from 20/100 to 20/25. Conclusion Small-gauge PPV may be utilized to remove dense dystrophic calcium deposits on the lens surface in lieu of IOL exchange. PMID:25045246
[Four-port pars plana vitrectomy for severe proliferative diabetic retinopathy].
Wei, Wen-bin; Yang, Qiong; Mo, Jing; Zhou, Dan
2008-01-01
To investigate the 4-port pars plana vitrectomy in eyes with severe proliferative diabetic retinopathy (PDR). It was a case-control study. Twenty-eight eyes in 27 patients with extensive fibrovascular proliferation associated with PDR were retrospectively collected, who were undergone 4-port pars plana vitreous surgery with bimanual manipulation techniques, such as membrane dissections and enbloc membranectomy. The control group consisted of 30 eyes in 30 patients with PDR which were undergone 3-port pars plana vitrectomy by the same surgeon. Twenty-eight eyes were undergone membrane dissection and enbloc membranectomy smoothly during 4-port pars plana vitrectomy, 2 iatrogenic holes occurred in 1 eye. During the follow up 7 months to 4.5 years, the retina was fully attached in all eyes, visual acuity had improved except 1 eye which complicated with neovascular glaucoma. In the control group, membranes partially remained in 2 eyes, 4 iatrogenic holes appeared in 3 eyes, neovascular glaucoma occurred in 3 eyes, the retina was reattached during the follow-up time from 12 to 34 months. For severe proliferative diabetic retinopathy, the 4-port pars plana vitrectomy with bimanual manipulations of membrane peeling is safe and efficiency.
Four-port bimanual 23-gauge vitrectomy for diabetic tractional retinal detachment.
Wang, Zhao-Yang; Zhao, Ke-Ke; Li, Jia-Kai; Rossmiller, Brian; Zhao, Pei-Quan
2016-06-01
Four-port bimanual vitrectomy is a surgical technique that facilitates removal of epiretinal membranes in severe proliferative diabetic retinopathy (PDR). As the illumination is held by the assistant through the fourth scleral incision, fibrovascular membranes are removed by bimanual manipulation techniques. The objective of this study was to evaluate the safety and efficacy of four-port bimanual 23-gauge vitrectomy for patients with tractional retinal detachment (TRD) in severe PDR. Retrospective, comparative, consecutive, interventional case series. Sixty-six eyes of 58 consecutive patients who underwent primary vitrectomy for severe diabetic TRD. Thirty-six eyes of 31 cases that were treated with four-port 23-gauge vitrectomy were compared with 30 eyes of 27 cases that were treated with 23-gauge pars plana vitrectomy (PPV). Main outcome measures were best-corrected visual acuity (BCVA), retinal status, intraocular pressure, and incidence of intraoperative and postoperative complications with at least 6 months of follow-up. The primary and ultimate anatomic success rates (94.4% versus 93.3%, and 100% in both groups, respectively) and the mean BCVA changes did not differ significantly between groups. The whole surgical time and the membrane removal time were significantly (p < 0.001, respectively) shorter in the four-port 23-gauge group than in the 23-gauge group. There was no difference in the incidence of intraoperative and postoperative complications in both groups. Four-port bimanual 23-gauge vitrectomy offers comparable anatomic success and shortens the surgical time compared with conventional 23-gauge PPV in patients with TRD resulting from severe PDR. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
IN VITRO FLOW ANALYSIS OF NOVEL DOUBLE-CUTTING, OPEN-PORT, ULTRAHIGH-SPEED VITRECTOMY SYSTEMS.
Zehetner, Claus; Moelgg, Marion; Bechrakis, Emmanouil; Linhart, Caroline; Bechrakis, Nikolaos E
2017-10-09
To analyze the performance and flow characteristics of novel double-cutting, open-port, 23-, 25-, and 27-gauge ultrahigh-speed vitrectomy systems. In vitro fluidic measurements were performed to assess the volumetric aspiration profiles of several vitrectomy systems in basic salt solution and egg white. Double-cutting open-port vitrectomy probes delivered stable aspiration flow rates that were less prone to flow variation affected by the cutting speed. Increase in cutting frequency to the maximum level resulted in flow reduction of less than 10% (0.0%-9.5%). Commercially available 23-, 25-, and 27-G double-cutting probes exhibited higher egg-white and basic salt solution flow rates at all evaluated cut rates, with aspirational efficiencies being 1.1 to 2.9 times the flow rates of standard single-blade vitrectomy probes of the same caliber at the maximum preset vacuum. The highest relative differences were observed at faster cut rates. The newly introduced double-cutting open-port vitrectomy probes delivered stable aspiration flow rates that were less prone to flow variation affected by the cutting speed. The fluidic principle of constant flow even at the highest cut rates and low vacuum levels might impact surgical strategies, especially when performing manipulations close to the retina.
Wang, Rui; Bi, Chun-Chao; Lei, Chun-Ling; Sun, Wen-Tao; Wang, Shan-Shan; Dong, Xiao-Juan
2014-01-01
AIM To describe clinical findings and complications from cases of traumatic lens subluxation/dislocation in patients with secondary glaucoma, and discuss the multiple treating methods of operation combined with primary intraocular lens (IOL) implantation. METHODS Non-comparative retrospective observational case series. Participants: 30 cases (30 eyes) of lens subluxation/dislocation in patients with secondary glaucoma were investigated which accepted the surgical treatment by author in the Ophthalmology of Xi'an No.4 Hospital from 2007 to 2011. According to the different situations of lens subluxation/dislocation, various surgical procedures were performed such as crystalline lens phacoemulsification, crystalline lens phacoemulsification combined anterior vitrectomy, intracapsular cataract extraction combined anterior vitrectomy, lensectomy combined anterior vitrectomy though peripheral transparent cornea incision, pars plana lensectomy combined pars plana vitrectomy, and intravitreal cavity crystalline lens phacofragmentation combined pars plana vitrectomy. And whether to implement trabeculectomy depended on the different situations of secondary glaucoma. The posterior chamber intraocular lenses (PC-IOLs) were implanted in the capsular-bag or trassclerally sutured in the sulus decided by whether the capsular were present. Main outcome measures: visual acuity, intraocular pressure, the situation of intraocular lens and complications after the operations. RESULTS The follow-up time was 11-36mo (21.4±7.13). Postoperative visual acuity of all eyes were improved; 28 cases maintained IOP below 21 mm Hg; 2 cases had slightly IOL subluxation, 4 cases had slightly tilted lens optical area; 1 case had postoperative choroidal detachment; 4 cases had postoperative corneal edema more than 1wk, but eventually recovered transparent; 2 cases had mild postoperative vitreous hemorrhage, and absorbed 4wk later. There was no postoperative retinal detachment, IOL dislocation, and endophthalmitis. CONCLUSION To take early treatment of traumatic lens subluxation/dislocation in patients with secondary glaucoma by individual surgical plan based on the different eye conditions would be safe and effective, which can effectively control the intraocular pressure and restore some vision. PMID:24790868
Takkar, Brijesh; Azad, Rajvardhan; Azad, Shorya; Rathi, Anubha
2015-01-01
AIM To describe a new surgical technique for managing dislocated sclerotic cataractous lens. METHODS Six patients with advanced posteriorly dislocated cataracts were operated at a tertiary care centre and analyzed retrospectively. After standard 3 port 23 G pars plana vitrectomy and perfluorocarbon liquid (PFCL) injection, the dislocated white cataract was held with occlusion using phaco fragmatome and then chopped into smaller pieces with a sharp tipped chopper using 25 G chandelier endoilluminator. Each piece was emulsified individually. Following aspiration of PFCL, Fluid Air Exchange was done in all the cases and surgery completed uneventfully. RESULTS Best corrected visual acuity (BCVA) in all the patients was better than 6/12 after one month of follow up. No serious complications were noted till minimum 6mo of follow up. CONCLUSION Four port posterior segment nucleotomy with a chandelier endoilluminator, fragmatome and a chopper appears to be a safe, easy and effective procedure for managing dislocated sclerotic cataractous nuclei. Ultrasonic energy used and adverse thermal effects of the fragmatome on the sclera may be lesser. PMID:26309887
Beebe, David C; Shui, Ying-Bo; Siegfried, Carla J; Holekamp, Nancy M; Bai, Fang
2014-05-01
Oxygen levels in the eye are generally low and tightly regulated. Oxygen enters the eye largely by diffusion from retinal arterioles and through the cornea. In intact eyes, oxygen from the retinal arterioles diffuses into the vitreous body. There is a decreasing oxygen gradient from the retina to the lens, established by oxygen consumption by ascorbate in the vitreous fluid and lens metabolism. Age-related degeneration of the vitreous body or removal during vitrectomy exposes the posterior of the lens to increased oxygen, causing nuclear sclerotic cataracts. Lowering oxygen in the vitreous, as occurs in patients with ischemic diabetic retinopathy, protects against cataracts after vitrectomy. Vitrectomy and cataract surgery increase oxygen levels at the trabecular meshwork and with it the risk of open angle glaucoma. Two additional risk factors for glaucoma, African heritage and having a thinner cornea, are also associated with increased oxygen in the anterior chamber angle. Preservation of the vitreous body and the lens, two important oxygen consumers, would protect against nuclear sclerotic cataracts and open angle glaucoma. Delaying removal of the lens for as long as possible after vitrectomy would be an important step in delaying ocular hypertension and glaucoma progression.
Gadkari, Salil S; Kulkarni, Sucheta R; Kamdar, Rushita R; Deshpande, Madan
2015-01-01
The management of retinopathy of prematurity (ROP) can be challenging in preterm babies with a gestational age <30 weeks, those with very low birth weight and multiple risk factors (eg., oxygen therapy for respiratory distress, sepsis, neonatal jaundice). A premature infant presented with "hybrid" zone 1 disease in the right eye and aggressive posterior ROP in the left eye. Both eyes were adequately treated with laser photocoagulation; however, the eyes deteriorated and progressed to stage 4 ROP. Both eyes eventually underwent intravitreal bevacizumab followed by lens sparing vitrectomy with good anatomical and visual outcome. Anticipation of progression despite laser photocoagulation in certain clinical scenarios, frequent follow-up and timely surgical intervention is paramount.
Lam, Dennis S C; Leung, Hiu Ying; Liu, Shu; Radke, Nishant; Yuan, Ye; Lee, Vincent Y W
2017-01-01
To study the safety and efficacy of 2-port pars plana anterior and central core vitrectomy (Lam floaterectomy) in combination with phacoemulsification (phaco) and intraocular lens implantation (IOL) for patients with cataract and significant floaters under topical anesthesia. Retrospective review of the first 50 consecutive cases. A standardized treatment protocol was used for patients with cataract and significant (moderate to severe) floaters (duration > 3 months). Data analysis included intraoperative and postoperative complications, floater status, and patient satisfaction. There were 50 eyes (38 patients) with a male-to-female ratio of 1 to 2.3. Twelve patients had bilateral eye surgeries. Mean age was 58.10 ± 9.85 years (range, 39-83). All patients completed the 3-month follow-up. One eye had mild vitreous hemorrhage at the end of surgery arising from sclerotomy wound oozing. No other intraoperative compli-cations were encountered. Postoperatively, there was 1 case of transient hypotony and 1 case of congestion at sclerotomy wound. No cases of retinal break or detachment, or clinically significant macular edema, were reported. There were 5 cases (10%) of mild residual floaters and 1 case (2%) of floater recurrence. Total floater clearance rate was 88%. Patient satisfaction rates were 80%, 14%, 6%, and 0% for very satisfied, satis-fied, acceptable, and unsatisfied, respectively. The 3-month results in terms of safety and efficacy of the Lam floaterectomy in combination with phaco and IOLfor patients with cataract and significant floaters under topical anesthesia are encouraging. Further larger-scale, prospective, multicenter studies seem warranted. Copyright© 2017 Asia-Pacific Academy of Ophthalmology.
Yeung, Ling; Wang, Nan-Kai; Wu, Wei-Chi; Chen, Kuan-Jen
2018-04-23
To evaluate the safety and efficacy of combined 23-gauge transconjunctival pars plana vitrectomy and scleral fixation of intraocular lens (IOL) without conjunctival dissection. A retrospective study in Chang Gung Memorial Hospital, Keelung and Taoyuan, Taiwan. Patients receiving combined 23-gauge transconjunctival pars plana vitrectomy and scleral fixation of IOL without conjunctival dissection were enrolled. The ocular findings, causes of lens complication, surgical procedures, type of IOL used, and complications were documented. We included 40 eyes from 39 patients (27 male, 12 female) with a mean age of 59.5 [standard deviation (±) 14.8] years old. The mean follow-up duration was 6.8 ± 5.4 months. The cause of lens complications was ocular trauma in 24 (60%) eyes, cataract surgery complications in 11 (28%) eyes, and spontaneous subluxation of crystalline lens in 5 (13%) eyes. The overall best corrected visual acuity (BCVA) (logMAR) improved from 1.359 ± 0.735 to 0.514 ± 0.582 (p < 0.001). The BCVA also improved significantly in each group with different causes of lens complications. Preoperative BCVA was the only factor associated with the postoperative visual outcome (p = 0.008). Most surgery-related complications were self-limited, including mild vitreous hemorrhage (5%), microhyphema (5%), transient elevated intraocular pressure (3%), and transient hypotony (3%). Cystoid macular edema and IOL decentration was found in 3 (8%) eyes and 1 (3%) eye respectively. Combined 23-gauge transconjunctival vitrectomy and scleral fixation of IOL without conjunctival dissection is effective and safe in managing a wide variety of lens complications, with good postoperative comfort and visual recovery. Retrospective study, not applicable.
Globe stability during simulated vitrectomy with valved and non-valved trocar cannulas
Abulon, Dina Joy; Charles, Martin; Charles, Daniel E
2015-01-01
Purpose To compare the effects of valved and non-valved cannulas on intraocular pressure (IOP), fluid leakage, and vitreous incarceration during simulated vitrectomy. Methods Three-port pars plana incisions were generated in six rubber eyes using 23-, 25-, and 27-gauge valved and non-valved trocar cannulas. The models were filled with air and IOP was measured. Similar procedures were followed for 36 acrylic eyes filled with saline solution. Vitreous incarceration was analyzed in eleven rabbit and twelve porcine cadaver eyes. Results In the air-filled model, IOP loss was 89%–94% when two non-valved cannulas were unoccupied versus 1%–5% when two valved cannulas were unoccupied. In the fluid-filled model, with non-valved cannulas, IOP dropped while fluid leaked from the open ports. With two open ports, the IOP dropped to 20%–30% of set infusion pressure, regardless of infusion pressure and IOP compensation. The IOP was maintained in valved cannulas when one or two ports were left open, regardless of IOP compensation settings. There was no or minimal fluid leakage through open ports at any infusion pressure. Direct microscopic analysis of rabbit eyes showed that vitreous incarceration was significantly greater with 23-gauge non-valved than valved cannulas (P<0.005), and endoscopy of porcine eyes showed that vitreous incarceration was significantly greater with 23-gauge (P<0.05) and 27-gauge (P<0.05) non-valved cannulas. External observation of rabbit eyes showed vitreous prolapse through non-valved, but not valved, cannulas. Conclusion Valved cannulas surpassed non-valved cannulas in maintaining IOP, preventing fluid leakage, and reducing vitreous incarceration during simulated vitrectomy. PMID:26445520
Kim, Yong Joon; Ha, Seung Joo
2013-01-01
To report a case of pupillary block glaucoma associated with spontaneous crystalline lens subluxation into the anterior chamber in a 34-year-old man. Dry vitrectomy was performed for securing enough retrolental space, and an intracapsular lens extraction was then performed via a corneolimbal incision. Additional endothelial cell damage was avoided with an injection of viscoelastics and gentle extraction of the crystalline lens. After deepening of the anterior chamber, scleral fixation of the intraocular lens was performed with an ab externo technique. Two months after the operation, a well-fixated intraocular lens was observed and intraocular pressure was stable. The postoperative corneal astigmatism was -3.5 dpt, and the patient had a best-corrected visual acuity of 20/25. Postoperative complications included decreased endothelial cell count and sector iris paralysis near the incision site. An anteriorly subluxated crystalline lens can cause pupillary block glaucoma in healthy young adults. To prevent intraoperative complications, intracapsular lens extraction with dry vitrectomy can be a good surgical option. The endothelial cell density should be closely monitored after surgery.
Cywinski, Adam; Piwonska-Lobermajer, Anna; Penter, Sandra
2016-08-01
A retrospective analysis of visual function and postoperative complaints in patients after posterior vitrectomy and multifocal Mplus or MplusX intraocular lens implantation. 14 patients (14 eyes) were enrolled in the study. All patients underwent posterior vitrectomy due to underlying retinal pathologies. A combined procedure of phacovitrectomy was performed in some patients, whereas others underwent a separate cataract extraction as a second stage of treatment. The Mplus or MplusX intraocular lenses were implanted in all cases and the postoperative visual function and patient complaints were analysed. Multifocal lens explantation was not necessary in any case. Good uncorrected distance and near visual acuity was achieved in most cases. When implanted prior to vitrectomy, the intraocular lenses did not limit the view into the posterior segment, so precise manipulations within the macula and peripheral retina were feasible. The right choice between Mplus and MplusX minimises the rate of postoperative complaints. Conslusions: The multifocal Mplus and MplusX intraocular lenses offer a good alternative for patients who need posterior vitrectomy and still want to achieve good uncorrected distance and near visual acuity.
Adhi, Mohammad Idrees; Siyal, Nisar; Aziz, Sumbul
2017-01-01
To study anatomical and functional outcomes of retinectomies in rhegmatogenous retinal detachments complicated by proliferative vitreoretinopathy. This is a retrospective interventional consecutive case series of eyes with rhegmatogenous retinal detachments complicated by advanced proliferative vitreoretinopathy and managed by relaxing retinectomy over a period of seventeen years. Three-port pars plana vitrectomy included core vitrectomy and removal of all epi-retinal membranes. On failure to flatten, retina was cut and excised. Basal vitrectomy and removal of anterior flap of retina then followed. Silicone oil was used as temponade in majority of cases. The dependent variables were anatomical and functional outcomes. The statistical analysis was performed on SPSS 21. Series included 370 eyes of 337 patients. Mean follow up was 39 months. Scleral explant was used in 90(24.39%) cases. Two hundred and nine (56.49%) eyes were operated with trans conjunctival sutureless vitrectomy technique. Procedure was bilateral in 33 patients (09.79%). Retina attached in 311(84.05%) eyes after initial surgery. Final re-attachment after one or more surgeries was achieved in 344(92.97%) eyes. Two hundred and eleven (57.02%) cases achieved visual acuity of 6/60 or better. Relaxing retinectomies have good and encouraging anatomical and functional outcomes. This surgery can be effectively carried out with trans conjunctival sutureless vitrectomy technique.
[Pars plana vitrectomy with the vitreous stripper].
Klöti, R
1975-01-01
We report on the construction and the function of a new microsurgical instrument for vitrectomy. The instrument is introduced into the vitreous cavity through a small scleral incision in the pars plana area. Microscope observation with slit-lamp illumination and a specially designed contact lens are used for this surgical procedure. Our clinical experiences and the indications are discussed.
Al-Badawi, Amer Hamad; Abdelhakim, Mohamad Amr Salah Eddin; Macky, Tamer Ahmed; Mortada, Hassan Aly
2018-04-30
To study anatomical and visual outcomes of pars plana vitrectomy (PPV) with non-fovea-sparing (entire) internal limiting membrane (ILM) peeling in eyes with myopic foveoschisis (MF). Prospective interventional case series of eyes undergoing PPV with entire ILM peeling for symptomatic MF. Preoperative spectral domain optical coherence tomography (SD - OCT) epiretinal membrane, anomalous posterior vitreous detachment, vitreoschisis and postoperative changes in SD-OCT central foveal thickness (CFT), ellipsoid zone defect, foveal detachment (FD), macular hole (MH) diameter (if present) and best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (logMAR). This study included 21 eyes (21 patients) with mean age 60.4±13.1, 15 females (71.4%). All patients achieved complete postoperative reattachment by SD-OCT (no FD) 6 months post vitrectomy, with no iatrogenic intraoperative or postoperative MH, and with significant improvement in final BCVA from 1.6±0.30 to1.0±0.2 logMAR, and in CFT from 918.2±311.4 to182.3±33.1 µm. Patients were subdivided into subgroup A: 11 eyes without MH; and subgroup B: 10 eyes with MH, the latter had significant improvement in MH diameter (p=0.005). Preoperative BCVA was a significant risk factor for visual gain, while preoperative FD and CFT were significant for CFT change. Vitrectomy with non-fovea-sparing (entire) ILM peeling resulted in a significant functional and anatomical improvement in eyes with MF with/without MH with no reported complications. Results are comparable to fovea-sparing ILM peeling. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Effect of humidity on posterior lens opacification during fluid-air exchange.
Harlan, J B; Lee, E T; Jensen, P S; de Juan, E
1999-06-01
To study the relationship of humidity and the rate of lens opacity formation during fluid-air exchange using an animal model. Vitrectomy and fluid-air exchange was carried out using 16 eyes of 8 pigmented rabbits. One eye of each rabbit was exposed to dry air and the fellow eye received humidified air using an intraocular air humidifier. In each case, the percent humidity of the intraocular air was measured using an in-line hygrometer. Elapsed time from initial air entry to lens feathering was recorded for each eye, with the surgeon-observer unaware of the percent humidity of the air infusion. In each rabbit, use of humidified air resulted in a delay in lens feathering (P<.02), with an overall increase in time to feathering of 80% for humidified air vs room air. Use of a humidifier during fluid-air exchange prolongs intraoperative lens clarity in the rabbit model, suggesting that humidified air should prolong lens clarity during phakic fluid-air exchange in patients. Use of humidified air during vitrectomy and fluid-air exchange may retard the intraoperative loss of lens clarity, promoting better visualization of the posterior segment and enhancing surgical performance.
Curvularia lunata endophthalmitis.
Berbel, Rodrigo Fabri; Casella, Antonio Marcelo Barbante; de Freitas, Denise; Höfling-Lima, Ana Luisa
2011-10-01
The aim of this study was to report a case of a 52-year-old man with a rare fungal endophthalmitis after penetrating ocular trauma with a fish hook. The patient was submitted to wound repair and hook extraction. Three weeks after the trauma, a cataract extraction with phacoemulsification and in-the-bag intraocular lens implantation was performed. After the development of endophthalmitis, vitrectomy and lens explantation with positive culture for Curvularia lunata were carried out. The infection was controlled with the administration of systemic itraconazole and intraocular voriconazole. The use of intravitreal voriconazole injection is a viable option in cases of Curvularia fungal endophthalmitis.
Caça, Ihsan; Sakalar, Yildirim Bayezit; Ari, Seyhmus; Alakus, Fuat; Dogan, Eyüp
2008-01-01
We evaluated the results of simultaneous bilateral cataract extraction with intraocular lens (IOL) inplantation 32 pediatric cataract patients. Simultaneous cataract extraction and posterior capsulotomy with anterior vitrectomy and IOL implantation is an effective and safe procedure in bilateral pediatric cataracts treatment.
One hundred consecutive cases of pars plana vitrectomy with the vitreous stripper.
Syrdalen, P
1979-01-01
The results of 100 consecutive cases of pars plana vitrectomy are reported. Vitrectomy was performed on accunt of complications of diabetic retinopathy (37 eyes), complicated retinal detachment (28 eyes), vitreous haemorrhage of various causes (17 eyes), vitreous haemorrhage and complications secondary to injuries (13 eyes) and secondary cataract or vitreous in the anterior chamber creating corneal dystrophy (5 eyes). With an average follow-up time of 14.2 months, vitrectomy resulted in visual improvement in 55 eyes, unchanged visual acuity in 24 eyes and reduced visual acuity in 21 eyes. The operative and postoperative complications were: secondary vitreous haemorrhage (11 eyes), retinal detachment (8 eyes), haemorrhagic glaucoma (7 eyes), retinal tears (5 eyes), lens injury (4 eyes), corneal dystrophy (2 eyes) and endophthalmitis (1 eye).
Anterior segment sparing to reduce charged particle radiotherapy complications in uveal melanoma
NASA Technical Reports Server (NTRS)
Daftari, I. K.; Char, D. H.; Verhey, L. J.; Castro, J. R.; Petti, P. L.; Meecham, W. J.; Kroll, S.; Blakely, E. A.; Chatterjee, A. (Principal Investigator)
1997-01-01
PURPOSE: The purpose of this investigation is to delineate the risk factors in the development of neovascular glaucoma (NVG) after helium-ion irradiation of uveal melanoma patients and to propose treatment technique that may reduce this risk. METHODS AND MATERIALS: 347 uveal melanoma patients were treated with helium-ions using a single-port treatment technique. Using univariate and multivariate statistics, the NVG complication rate was analyzed according to the percent of anterior chamber in the radiation field, tumor size, tumor location, sex, age, dose, and other risk factors. Several University of California San Francisco-Lawrence Berkeley National Laboratory (LBNL) patients in each size category (medium, large, and extralarge) were retrospectively replanned using two ports instead of a single port. By using appropriate polar and azimuthal gaze angles or by treating patients with two ports, the maximum dose to the anterior segment of the eye can often be reduced. Although a larger volume of anterior chamber may receive a lower dose by using two ports than a single port treatment. We hypothesize that this could reduce the level of complications that result from the irradiation of the anterior chamber of the eye. Dose-volume histograms were calculated for the lens, and compared for the single and two-port techniques. RESULTS: NVG developed in 121 (35%) patients. The risk of NVG peaked between 1 and 2.5 years posttreatment. By univariate and multivariate analysis, the percent of lens in the field was strongly correlated with the development of NVG. Other contributing factors were tumor height, history of diabetes, and vitreous hemorrhage. Dose-volume histogram analysis of single-port vs. two-port techniques demonstrate that for some patients in the medium and large category tumor groups, a significant decrease in dose to the structures in the anterior segment of the eye could have been achieved with the use of two ports. CONCLUSION: The development of NVG after helium-ion irradiation is correlated to the amount of lens, anterior chamber in the treatment field, tumor height, proximity to the fovea, history of diabetes, and the development of vitreous hemorrhage. Although the influence of the higher LET deposition of helium-ions is unclear, this study suggests that by reducing the dose to the anterior segment of the eye may reduce the NVG complications. Based on this retrospective analysis of LBNL patients, we have implemented techniques to reduce the amount of the anterior segment receiving a high dose in our new series of patients treated with protons using the cyclotron at the UC Davis Crocker Nuclear Laboratory (CNL).
Tissue glue in sutureless vitreoretinal surgery for the treatment of wound leakage.
Batman, Cosar; Ozdamar, Yasemin; Aslan, Ozlem; Sonmez, Kenan; Mutevelli, Seda; Zilelioglu, Guler
2008-01-01
To assess the surgical outcomes of the use of tissue glue to close sclerotomy sites when required and the views of ultrasound biomicroscopy of the sclerotomy sites in 23- and 25-gauge vitrectomy systems. A 25-gauge transconjunctival sutureless vitrectomy was performed in 38 eyes and a 23-gauge transconjunctival sutureless vitrectomy was performed in 46 eyes for various vitreoretinal diseases. Wound leakage occurred at the sclerotomy sites at the end of the surgery in 6 eyes with 23-gauge transconjunctival sutureless vitrectomy and 7 eyes with 25-gauge transconjunctival sutureless vitrectomy. The sclerotomy sites were closed by using tissue glue to prevent wound leakage and evaluated with ultrasound biomicroscopy postoperatively. No wound leakage was observed at the end of the surgical procedure or during the follow-up period. Abnormal fibrous ingrowth was not detected at the sclerotomy sites by means of ultrasound biomicroscopy. The results demonstrated the efficacy of tissue glue for closing site ports when wound leakage is observed in transconjunctival sutureless vitreoretinal surgery.
Sun, I-Ting; Lee, Tsung-Han; Chen, Chih-Hsin
2017-01-01
We report a case of rapid cataract progression after Nd:YAG vitreolysis for vitreous floaters. A 55-year-old man presented with acute onset of blurred vision following Nd:YAG vitreolysis for symptomatic floaters in the left eye. His initial best corrected visual acuity (BCVA) was 20/1,000 in the left eye. Ocular examinations showed frost-like opacities of the lens and a suspected break of the posterior capsule in the left eye. There were no detectable retinal lesions. Cataract surgery was then arranged. Posterior capsular rupture and vitreous loss occurred during surgery, which required a subsequent pars plana vitrectomy. After the surgery, BCVA in the left eye gradually improved to 20/20 and was maintained during a 1-year follow-up period. Crystalline lens injuries and rapid cataract progression may occur following Nd:YAG vitreolysis. While dealing with this type of complicated cataract, clinicians should be aware of the possibility of posterior lens capsule rupture during surgery and the need for combined vitrectomy.
Corneal approach 20 Guage vitrectomy system for the management of congenital cataract
Memon, Mariya Nazish; Bukhari, Sadia; Bhutto, Israr Ahmed
2016-01-01
Objective: To evaluate the efficacy and complications of 20 gauge vitrectomy via corneal approach for the management of congenital cataract. Method: We performed anterior capsular vitreorhexis, lens matter aspiration (LMA), primary posterior vitrectorhexis and anterior vitrectomy via corneal approach using 20 gauge vitrectomy system in children younger than two years of age with congenital cataract between January 2014 to December 2014. The intra and postoperative complications were observed. Results: Twenty nine eyes of 21 children were included in this study. Congenital cataract surgery using 20 gauge vitrectomy system via corneal approach did not reveal any intra operative complication. Post operatively all children were able to freely open their operated eyes. Conjunctival congestion at the incision site in four eyes and mild anterior chamber reaction in 8 eyes were seen on 1st daywhich resolved at one week follow up. Other major post operative complications such as inflammatory membrane, irregular pupil, posterior/anterior syneache and opacification of visual axis were not seen during follow up period. Conclusion: The 20-gauge vitrectomy system via corneal approach is easy to perform, is less time consuming, safe and effective for the management of congenital cataract in younger children. PMID:27182257
Corneal approach 20 Guage vitrectomy system for the management of congenital cataract.
Memon, Mariya Nazish; Bukhari, Sadia; Bhutto, Israr Ahmed
2016-01-01
To evaluate the efficacy and complications of 20 gauge vitrectomy via corneal approach for the management of congenital cataract. We performed anterior capsular vitreorhexis, lens matter aspiration (LMA), primary posterior vitrectorhexis and anterior vitrectomy via corneal approach using 20 gauge vitrectomy system in children younger than two years of age with congenital cataract between January 2014 to December 2014. The intra and postoperative complications were observed. Twenty nine eyes of 21 children were included in this study. Congenital cataract surgery using 20 gauge vitrectomy system via corneal approach did not reveal any intra operative complication. Post operatively all children were able to freely open their operated eyes. Conjunctival congestion at the incision site in four eyes and mild anterior chamber reaction in 8 eyes were seen on 1(st) daywhich resolved at one week follow up. Other major post operative complications such as inflammatory membrane, irregular pupil, posterior/anterior syneache and opacification of visual axis were not seen during follow up period. The 20-gauge vitrectomy system via corneal approach is easy to perform, is less time consuming, safe and effective for the management of congenital cataract in younger children.
Owens, S L; Lam, S; Tessler, H H; Deutsch, T A
1993-04-01
Late endophthalmitis, due to Propionibacterium acnes, developed in three patients following uncomplicated extracapsular cataract extraction and posterior chamber intraocular lens (PC-IOL) insertion. Cultures from the capsular bag yielded P. acnes in all three. With topical anesthesia and through an anterior chamber paracentesis, culture specimens were taken from and clindamycin irrigated into the capsular bag. Filtered 100% oxygen was introduced into the anterior chamber in two; the third also received an injection of gentamicin and dexamethasone into the capsular bag. After treatment, two patients received oral antibiotics; one received hyperbaric oxygen therapy. Visual acuity was improved and inflammation reduced in all three. However, after treatment, ocular toxic effects due to clindamycin were suspected in one. This approach offers several clear advantages, including topical anesthesia, outpatient management, elimination of the need for vitrectomy, and retention of the intraocular lens (IOL).
Yu, Jianchun; Chen, Xing; Zhou, Danying; Shen, Jian; Wu, Yanbing; Sun, Qingzhu
2018-06-10
BACKGROUND Currently, safe and effective surgical treatment of malignant glaucoma is still under investigation. This study evaluated the clinical efficacy of ciliary ring incision combined with modified partial pars plana vitrectomy in the treatment of malignant glaucoma. The technique is particularly useful in the treatment of "phakic" patients with malignant glaucoma, especially those who wish to preserve the natural lens. MATERIAL AND METHODS We retrospectively analyzed 13 cases (16 eyes) of malignant glaucoma in which patients underwent ciliary ring incision combined with modified partial pars plana vitrectomy based on follow-up data collected from May 2004 to March 2017. The data we analyzed included postoperative best-corrected visual acuity(BCVA), intraocular pressure (IOP), anterior chamber depth (ACD), optic cup changes, and surgical complications; some patients underwent visual field tracking. The mean follow-up period was 33.1±10.6 (range, 19-46) months. RESULTS A statistically significant number of eyes had improved visual acuity 1 year after surgery compared with the preoperative difference (Z=-3.853, P=0.000). Increases in the mean anterior chamber depth and decreases in the mean IOP measured at the 1-week and the 1-year follow-ups were also statistically significant. There were no serious complications during the follow-up period. CONCLUSIONS Ciliary ring incision combined with modified partial pars plana vitrectomy for malignant glaucoma not only provided a clear and reliable intraoperative vitrectomy channel, but it also caused less disturbance of intraocular tissue structure and fewer complications. It also has the advantage of preserving the lens and avoiding further damage to the anatomy in the anterior segment of the eye.
Vitrectomy-assisted phacoemulsification for lenticular coloboma.
Agarwal, Ashvin; Narang, Priya; Agarwal, Amar
2017-02-01
We describe a technique to prevent continuous vitreous hydration during phacoemulsification in eyes with lenticular coloboma. The hydration results from communication between the anterior and posterior chambers from the edges of the colobomatous defect. To avoid this, a valved trocar is placed at the pars plana site around the area of the lenticular defect, which allows a limited dry vitrectomy during phacoemulsification. Intermittent vitrectomy with a moderate cutting rate and low vacuum parameters accompanied by temporary halting of the phacoemulsification procedure prevents vitreous herniation into the anterior chamber and limits the extension of zonular compromise, facilitating safe phacoemulsification with appropriate capsule expansion and fixation devices and implantation of an intraocular lens. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Duwel, D; Lamba, M; Elson, H
Purpose: Various cancers of the eye are successfully treated with radiotherapy utilizing one anterior-posterior (A/P) beam that encompasses the entire content of the orbit. In such cases, a hanging lens shield can be used to spare dose to the radiosensitive lens of the eye to prevent cataracts. Methods: This research focused on Monte Carlo characterization of dose distributions resulting from a single A-P field to the orbit with a hanging shield in place. Monte Carlo codes were developed which calculated dose distributions for various electron radiation energies, hanging lens shield radii, shield heights above the eye, and beam spoiler configurations.more » Film dosimetry was used to benchmark the coding to ensure it was calculating relative dose accurately. Results: The Monte Carlo dose calculations indicated that lateral and depth dose profiles are insensitive to changes in shield height and electron beam energy. Dose deposition was sensitive to shield radius and beam spoiler composition and height above the eye. Conclusion: The use of a single A/P electron beam to treat cancers of the eye while maintaining adequate lens sparing is feasible. Shield radius should be customized to have the same radius as the patient’s lens. A beam spoiler should be used if it is desired to substantially dose the eye tissues lying posterior to the lens in the shadow of the lens shield. The compromise between lens sparing and dose to diseased tissues surrounding the lens can be modulated by varying the beam spoiler thickness, spoiler material composition, and spoiler height above the eye. The sparing ratio is a metric that can be used to evaluate the compromise between lens sparing and dose to surrounding tissues. The higher the ratio, the more dose received by the tissues immediately posterior to the lens relative to the dose received by the lens.« less
Das, T; Sharma, S; Singh, J; Rao, V; Chalam, K V
2001-01-01
Wide-field vitrectomy contact lenses are currently sterilized with ethylene oxide gas, and other lenses with autoclaving. To maintain a large inventory or possibly run the risk of loss of lens quality with repeated autoclaving, glutaraldehyde 2% and povidone iodine 5% solution were evaluated as possible sterilizing agents. Ethylene oxide presterilized lenses were contaminated with known concentrations (10(5) organisms/mL) of bacteria (S. epidemidis, P. aeruginosa, B. subtilis), and fungi (A. flavus, C. albicans) for 5 minutes. The test lenses were treated with glutaraldehyde or povidone iodine for 5, 10, 30, 60, and 120 minutes, and controls with sterilized water for a similar duration. Following treatment, both test and control lenses were sampled with sterile cotton swabs. The swabs were cultured for bacteria (tryptone soya broth 48 hours), and fungi (Saubourd's dextrose broth 5 days). The culture was negative for both glutaraldehyde- and povidone iodine-treated lenses against all organisms at all time points except B subtilis, which needed 120 minutes treatment. Two hours contact time with glutaraldehyde 2% or providone iodine 5% can sterilize vitrectomy contact lenses against common bacteria and fungi without affecting lens quality.
Bajgai, Priya; Tigari, Basavraj; Singh, Ramandeep
2017-10-04
To compare the outcome of 23-gauge as compared with 25-gauge transconjunctival sutureless vitrectomy (TSV) in the management of dislocated intraocular lenses (IOLs). Retrospective, non-consecutive, comparative, interventional case series. Patients with dislocated intraocular lens who underwent sutureless PPV using either 23-gauge or 25-gauge instruments. The patients who presented with a dislocated IOL, underwent TSV with repositioning of the intraocular lens, either in the sulcus or scleral-fixated sutured/glued. Of the total 61 eyes, 33 (54.09%) underwent 23-gauge TSV and 28 (45.90%) underwent 25-gauge TSV. The mean logMAR BCVA at baseline and 6 months after surgery was 0.8 and 0.46 in the 23-gauge group, and 0.82 and 0.47 in the 25-gauge group. There was no significant difference in logMAR BCVA values between the two groups at any time point of time during the follow-up. The mean postoperative IOP on postoperative day 1 was 14.76 ± 5.4 in 23-gauge group and 17.57 ± 7.9 in the 25-gauge group (p = 0.10). Retinal break was noticed intraoperatively in two cases in 23-gauge group and in three cases in 25-gauge group (p = 0.509). Postoperative complications included IOL decentration in one case of 23-gauge vitrectomy and two cases in 25-gauge group (p = 0.5), cystoid macular edema in four patients in 23-gauge group and six cases of 25-gauge group (p = 0.3) and retinal detachment in one case in each group (p = 0.9). 25-gauge appears to be as safe and as effective as 23-gauge TSV in the management of dislocated intraocular lenses.
Sun, I-Ting; Lee, Tsung-Han; Chen, Chih-Hsin
2017-01-01
Purpose We report a case of rapid cataract progression after Nd:YAG vitreolysis for vitreous floaters. Case Report A 55-year-old man presented with acute onset of blurred vision following Nd:YAG vitreolysis for symptomatic floaters in the left eye. His initial best corrected visual acuity (BCVA) was 20/1,000 in the left eye. Ocular examinations showed frost-like opacities of the lens and a suspected break of the posterior capsule in the left eye. There were no detectable retinal lesions. Cataract surgery was then arranged. Posterior capsular rupture and vitreous loss occurred during surgery, which required a subsequent pars plana vitrectomy. After the surgery, BCVA in the left eye gradually improved to 20/20 and was maintained during a 1-year follow-up period. Conclusion Crystalline lens injuries and rapid cataract progression may occur following Nd:YAG vitreolysis. While dealing with this type of complicated cataract, clinicians should be aware of the possibility of posterior lens capsule rupture during surgery and the need for combined vitrectomy. PMID:28626418
Tognetto, Daniele; Pastore, Marco R; Cirigliano, Gabriella; DʼAloisio, Rossella; Borelli, Massimo; De Giacinto, Chiara
2017-11-16
To investigate long-term intraocular pressure trends after uncomplicated pars plana vitrectomy for idiopathic epiretinal membrane. Three hundred and sixty-eight eyes of 368 consecutive patients were enrolled. Changes in intraocular pressure 1, 3, 6, and 12 months after surgery and during the final follow-up visit were evaluated in vitrectomized eyes and nonvitrectomized fellow eyes. The median follow-up period was 36 months (range 12-92 months). Longitudinal data analysis evidenced a 2.5-mmHg (2.2 mmHg; 2.7 mmHg, 95% confidence interval) statistically significant difference in intraocular pressure 30 days after surgery between treated and fellow untreated eyes, gradually recovering to a not significant 0.2-mmHg (-0.1 mmHg; 0.4 mmHg, 95% confidence interval) difference within 26 months. The incidence of late-onset ocular hypertension was 5.7% (21 over 347, 2%; 12%, 95% confidence interval) without difference between the treated eyes and the group control. No significant difference in the incidence of late-onset ocular hypertension and sex, lens status, or gauge of vitrectomy instruments was detected. Only patient's age was significantly higher (mean difference 4.2 years; 0.1-8.0 years, Monte Carlo, 95% confidence interval) in those who developed late-onset ocular hypertension in the vitrectomized eye. Uncomplicated pars plana vitrectomy for idiopathic epiretinal membrane seems not to increase the risk of late-onset ocular hypertension or open-angle glaucoma development.
Sakamoto, Masashi; Hashimoto, Ryuya; Yoshida, Izumi; Maeno, Takatoshi
2018-01-01
We retrospectively reviewed patients with postoperative neovascular glaucoma (NVG) after vitrectomy for proliferative diabetic retinopathy to investigate how variables assessed before, during, and after vitrectomy are associated with the requirement for filtration surgery. The subjects in this retrospective, observational, comparative study were 55 consecutive patients (61 eyes) who underwent vitrectomy for proliferative diabetic retinopathy at Toho University Sakura Medical Center between December 2011 and November 2016, were followed up for at least 6 months after surgery, and developed NVG within 2 years after surgery. They comprised 44 men and 11 women of mean age 52.4±9.1 years, who were followed up for a mean 7.1±6.1 months. We collected data on the following 16 variables: sex, age, history of panretinal photocoagulation completed within 3 months before vitrectomy, presence/absence of a lens, obvious iris/angle neovascularization, tractional retinal detachment, diabetic macular edema, vitreous hemorrhage, visual acuity and intraocular pressure before vitrectomy and at the onset of NVG, glycated hemoglobin, fasting blood glucose, estimated glomerular filtration rate, and use of intraoperative gas tamponade. Logistic regression analysis with the backward elimination method identified preoperative fasting hyperglycemia ( P =0.08), high intraocular pressure at the onset of NVG ( P =0.04), and use of gas tamponade during vitrectomy ( P =0.008) to be significant risk factors for requirement of filtration surgery. Preoperative fasting hyperglycemia, high intraocular pressure at the onset of NVG, and use of gas tamponade during vitrectomy predispose patients to require filtration surgery in the event of postoperative NVG.
Traumatic anterior dislocation of the crystalline lens and its surgical management.
Srećković, Sunčica; Janićijević Petrović, Mirjana; Jovanović, Svetlana; Paunović, Svetlana; Sarenac, Tatjana
2012-02-01
This paper reports a case of a 57-year old female who had sustained a blunt ocular trauma resulting in anterior dislocation of the crystalline lens and acute painful visual loss in the left eye. The patient was managed with anterior chamber intracapsular phacoemulsification through a small anterior capsulotomy, pars plana vitrectomy, and surgical iridotomy. Aphakia was corrected by a contact lens. Two months after the surgery, the best corrected visual acuity was 0.9 in the left eye. The vision and retina remained stable in her follow-up examination 1 year later. Anterior dislocation of the crystalline lens can cause severe complications so that dislocated lens should be removed immediately.
Cornut, P-L; Soldermann, Y; Robin, C; Barranco, R; Kerhoas, A; Burillon, C
2013-12-01
To report the financial impact of using modern lens and vitreoretinal surgical techniques. Bottom-up sterilization and consumables costs for new surgical techniques (microincisional coaxial phacoemulsification and transconjunctival sutureless vitrectomy) and the corresponding former techniques (phacoemulsification with 3.2-mm incision and 20G vitrectomy) were determined. These costs were compared to each other and to the target costs of the Diagnosis Related Groups for public hospitals (Groupes Homogènes de Séjours [GHS]) concerned, extracted from the analytic accounting data of the French National Cost Study (Étude Nationale des Coûts [ENC]) for 2009 (target=sum of sterilization costs posted under medical logistics, consumables, implantable medical devices, and special pharmaceuticals posted as direct expenses). For outpatient lens surgery with or without vitrectomy (GHS code: 02C05J): the ENC's target cost for 2009 was 339€ out of a total of 1432€. The cost detailed in this study was 4 % higher than the target cost when the procedure was performed using the former technique (3.2mm sutured incision) and 12 % lower when the procedure was performed using the new technique (1.8mm sutureless) after removing now unnecessary consumables and optimization of the technique. For level I retinal detachment surgeries (GHS code: 02C021): the ENC's 2009 target cost was 641€ out of a total of 3091€. The cost specified in this study was 1 % lower than the target cost when the procedure was done using the former technique (20-G vitrectomy) and 16 % less when the procedure was performed using the new technique (transconjunctival vitrectomy) after removal of now unnecessary consumables and optimization of the technique. Contrary to generally accepted ideas, implementing modern techniques in ocular surgery can result in direct cost and sterilization savings when the operator takes advantage of the possibilities these techniques offer in terms of simplification of the procedures to do away with consumables that are no longer necessary. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
[Surgical managment of retinal detachment].
Haritoglou, C; Wolf, A
2015-05-01
The detachment of the neurosensory retina from the underlying retinal pigment epithelium can be related to breaks of the retina allowing vitreous fluid to gain access to the subretinal space, to exudative changes of the choroid such as tumours or inflammatory diseases or to excessive tractional forces exerted by interactions of the collagenous vitreous and the retina. Tractional retinal detachment is usually treated by vitrectomy and exudative detachment can be addressed by treatment of the underlying condition in many cases. In rhegmatogenous retinal detachment two different surgical procedures, vitrectomy and scleral buckling, can be applied for functional and anatomic rehabilitation of our patients. The choice of the surgical procedure is not really standardised and often depends on the experience of the surgeon and other more ocular factors including lens status, the number of retinal breaks, the extent of the detachment and the amount of preexisting PVR. Using both techniques, anatomic success rates of over 90 % can be achieved. Especially in young phakic patients scleral buckling offers the true advantage to prevent the progression of cataract formation requiring cataract extraction and intraocular lens implantation. Therefore, scleral buckling should be considered in selected cases as an alternative surgical option in spite of the very important technical refinements in modern vitrectomy techniques. Georg Thieme Verlag KG Stuttgart · New York.
Station Module Move in 4K Video Resolution
2015-06-09
Robotics flight controllers in Mission Control Houston and Canada detached the large Permanent Multipurpose Module (PMM), used as a supply depot on the orbital laboratory, from the Earth-facing port of the Unity module and robotically relocated it to the forward port of the Tranquility module. This move cleared the Unity port for its conversion into the spare berthing location for U.S. cargo spacecraft; the Earth-facing port on Harmony is the primary docking location. Harmony’s space-facing port currently is the spare berthing location for cargo vehicles, so this move frees that location to be used in conjunction with Harmony’s forward port as the arrival locations for commercial crew spacecraft.
Wong, Robert W; Rhodes, Kyle M
2015-01-01
To describe a case of endophthalmitis after cataract surgery caused by Staphylococcus hominis and two separate colony types of Staphylococcus haemolyticus. Retrospective chart review including ophthalmic examination, intraocular biopsy and cultures, and anterior segment photography. A patient presented with endophthalmitis 1 month after cataract surgery. The patient underwent pars plana vitrectomy with vitreous fluid, aqueous fluid, and lens capsule biopsy with injection of intravitreal antimicrobials with full resolution of the infection. Cultures isolated grew S. hominis and two different colonies of S. haemolyticus, all sensitive to vancomycin. To the best of the authors' knowledge, this is the first case of endophthalmitis due to lens capsule seeding from three different types of bacteria, S. hominis and two different colony types of S. haemolyticus. Prompt diagnosis and treatment can be associated with good visual outcomes.
Management of corneal decompensation 4 decades after Sputnik intraocular lens implantation.
Hirji, Nashila; Nanavaty, Mayank A
2015-01-01
We report an unusual case of corneal decompensation occurring four decades after complicated cataract extraction with implantation of a Sputnik intraocular lens (IOL) and highlight the clinical and practical issues faced in managing corneal decompensation with a Sputnik IOL. A 72-year-old woman presented with deterioration of the vision in her left eye, four decades after intracapsular cataract extraction with Sputnik IOL implantation. Ocular examination revealed diffuse corneal edema and thickened vitreous strands in the anterior chamber. Her best-corrected visual acuity (BCVA) worsened to 6/60 within 3 months. Anterior vitrectomy and inferior iridectomy combined with Desçemet-stripping automated endothelial keratoplasty was performed. The procedure was successful, with the patient achieving best-corrected visual acuity of 6/6 at 8 months postoperatively. Corneal decompensation after Sputnik IOL implantation can occur four decades later. When the historical preoperative visual acuity is good in such cases, careful anterior vitrectomy with Desçemet-stripping automated endothelial keratoplasty provides good visual rehabilitation.
Management of iatrogenic crystalline lens injury occurred during intravitreal injection.
Erdogan, Gurkan; Gunay, Betul Onal; Unlu, Cihan; Gunay, Murat; Ergin, Ahmet
2016-08-01
To evaluate the approach to management of iatrogenic crystalline lens injury occurred during intravitreal injection (IVI). The patients who were managed operatively or followed-up without intervention after the iatrogenic lens injury due to IVI were included in the study. Capsular breaks remained either quiescent or resulted in cataract formation in the patients with inadvertent crystalline lens capsule damage. Phacoemulsification surgery was performed in patients with cataract formation with lower fluidic settings. A total of 9 cases included in the study. Seven cases underwent phacoemulsification with intraocular lens implantation. Two cases remained as quiescent lens injury during the follow-up. In 2 cases, dislocation of lens fragments occurred during phacoemulsification where pars plana vitrectomy was performed at the same session. After iatrogenic crystalline lens injury, capsular damage could remain quiescent or progress to cataract formation. Although phacoemulsification surgery can be performed with appropriate parameters, lens fragment dislocation can be observed in cases with traumatic lens damage secondary to IVI.
Kiyokawa, Masatoshi; Sakuma, Toshiro; Hatano, Noriko; Mizota, Atsushi; Tanaka, Minoru
2009-06-01
The purpose of this article is to report the characteristics and advantages of using a newly designed quartz contact lens with slit illumination from an operating microscope for intraocular surgery. The new contact lens is made of quartz. The lens is convex-concave and is used in combination with slit illumination from an operating microscope. The optical properties of quartz make this lens less reflective with greater transmittance. The combination of a quartz contact lens with slit illumination provided a brighter and wider field of view than conventional lenses. This system enabled us to perform bimanual vitrectomy and scleral buckling surgery without indirect ophthalmoscope. Small intraocular structures in the posterior pole or in the periphery were detected more easily. In conclusion, the newly designed quartz lens with slit beam illumination from an operating microscope provided a bright, clear and wide surgical field, and allowed intraocular surgery to be performed more easily.
Cataract Avoidance With Proton Therapy in Ocular Melanomas.
Thariat, Juliette; Jacob, Sophie; Caujolle, Jean-Pierre; Maschi, Celia; Baillif, Stéphanie; Angellier, Gaelle; Mathis, Thibaud; Rosier, Laurence; Carnicer, Adela; Hérault, Joel; Salleron, Julia
2017-10-01
The lens is a radiosensitive organ. Any dose of cephalic irradiation can give rise to radiation-induced cataracts. Contrary to other forms of radiotherapy, proton therapy (PT) can spare all or part of the lens due to accurate dose deposition. We investigated whether a lens-sparing approach was relevant to avoid cataracts in uveal melanoma patients. Patients were referred for PT from onco-ophthalmologists of private and academic institutions. Patients without preexisting cataracts or implants were entered in a prospective database. Dose thresholds responsible for cataracts were investigated in volumes of lens or lens periphery. Lens opacifications and de novo vision-impairing cataracts (VICs) had biannual follow up by ophthalmologists blinded to lens dose. Correlations between dose-volume relationships and VICs were assessed using univariate/multivariate regressions. Between 1991 and 2015, 1696 uveal melanoma patients were consecutively treated with PT. After a median follow up of 48 months, 14.4% and 8.7% of patients had cataracts and VIC within median times of 19 and 28 months, respectively. Median values of mean lens and lens periphery doses were 1.1 (radiobiologically effective [RBE] dose in photon-equivalent grays [GyRBE]) and 6.5 GyRBE, respectively. The lens received no dose in 25% of the patients. At an irradiated lens volume of ≤5%, there was no significantly increased risk for VIC below a dose of 10 GyRBE. A lens-sparing approach is feasible and results not only in reduced need for cataract surgery but also in better fundus-based tumor control. Reassessment of radioprotection rules for lens dose thresholds may follow.
Yokoyama, Sho; Kojima, Takashi; Kaga, Tatsushi; Ichikawa, Kazuo
2015-01-01
We report three asteroid hyalosis cases in which internal higher-order aberrations (HOAs) were improved concomitant with improved visual symptoms after vitrectomy. Cases 1 and 2 reported severe floaters and glare disability, although their visual acuities were fairly good. Case 3 showed poor visual acuity since this patient also suffered from mild macular degeneration. For these three asteroid hyalosis cases, we were unsure if treatment with vitrectomy could improve visual symptoms. Therefore, we measured internal HOAs with an aberrometer, and found that the internal HOA values in these cases were high. We suspected that internal high HOAs values were associated with visual disturbance, and performed vitrectomy. After the vitrectomy, the internal HOA values in these three asteroid hyalosis cases markedly decreased, and visual symptoms improved. These observations suggested that measurement of internal HOAs may be useful to determine the indication for vitrectomy. PMID:26698200
Yokoyama, Sho; Kojima, Takashi; Kaga, Tatsushi; Ichikawa, Kazuo
2015-12-23
We report three asteroid hyalosis cases in which internal higher-order aberrations (HOAs) were improved concomitant with improved visual symptoms after vitrectomy. Cases 1 and 2 reported severe floaters and glare disability, although their visual acuities were fairly good. Case 3 showed poor visual acuity since this patient also suffered from mild macular degeneration. For these three asteroid hyalosis cases, we were unsure if treatment with vitrectomy could improve visual symptoms. Therefore, we measured internal HOAs with an aberrometer, and found that the internal HOA values in these cases were high. We suspected that internal high HOAs values were associated with visual disturbance, and performed vitrectomy. After the vitrectomy, the internal HOA values in these three asteroid hyalosis cases markedly decreased, and visual symptoms improved. These observations suggested that measurement of internal HOAs may be useful to determine the indication for vitrectomy. 2015 BMJ Publishing Group Ltd.
Retinal damage caused by air-fluid exchange during pars plana vitrectomy.
Yang, Sam S; McDonald, H Richard; Everett, A I; Johnson, Robert N; Jumper, J Michael; Fu, Arthur D
2006-03-01
To report two cases of retinal damage associated with air infusion during pars plana vitrectomy. Observational case report. The authors reviewed the course of two patients who had retinal damage during par plana vitrectomy and air-fluid exchange for the treatment of macular hole and optic pit-related macular detachment, respectively. The intraoperative observations, postoperative course, and outcomes were reported. As a result of high air infusion flow during air-fluid exchange, retinal damage was created in the area contralateral to the infusion port. In Case 1, an oval area of whitening was noted on the first postoperative day. This area subsequently developed into a large retinal break associated with retinal detachment. In the second case, retinal whitening was noted intraoperatively. This region of pallor resolved quickly during the early postoperative period but resulted in a corresponding inferotemporal visual field defect. High infusion flow during air-fluid exchange in eyes undergoing vitrectomy surgery may result in significant retinal damage. This pressure-induced trauma initially causes retinal whitening that may be seen intraoperatively or during the early postoperative period. The region of damaged retina may develop a retinal break and detachment or a corresponding visual field defect.
INTRAOCULAR LENS SCAFFOLD TO PREVENT INTRAOCULAR FOREIGN BODY SLIPPAGE.
Agarwal, Amar; Ashok Kumar, Dhivya; Agarwal, Athiya
2017-01-01
To report the application of intraocular lens (IOL) scaffold technique in intraocular foreign body (IOFB) removal. Patient with IOFB in posterior segment is included. The IOFB is retrieved from the posterior segment (pars plana vitrectomy and exteriorization of the IOFB from the retinal surface using an intravitreal forceps via the posterior capsulotomy) and placed on the iris. A three-piece posterior chamber IOL is placed in the sulcus via the clear corneal incision. IOFB is then removed from the anterior chamber over the IOL by forceps. Metallic IOFB of 4 mm × 3 mm has been retrieved by IOL scaffold technique after rescuing it from the posterior segment. There has been no drop or slip of IOFB in the vitreous during removal. Posterior chamber IOL served as scaffold during IOFB removal from anterior chamber. The IOL scaffold maneuver has shown to prevent slippage by acting as a barrier between the IOFB and the vitreous.
Lens-induced astigmatism after perforating scleral injury.
Ludwig, Klaus; Moradi, Said; Rudolph, Guenther; Boergen, Klaus Peter
2002-10-01
Within 6 weeks of a penetrating scleral injury that included vitreous prolapse, a 6-year-old boy developed lenticular astigmatism with a regular component of 5.5 diopters (D). Visible indentational folds in the posterior lens capsule, caused by anterior vitreous fibers and anterior hyaloid, were presumed to be the origin of the astigmatism. Because of decreased visual acuity and the suspicion of early amblyopia, a pars plana vitrectomy with removal of the anterior hyaloid and the critical anterior vitreous fibers was performed. Dense fibrotic tissue between the lens equator and the site of the original scleral perforation limited reduction of the preoperative astigmatism to 4.0 D. However, the striae-like lenticular deformation disappeared completely, and full visual acuity was restored. During the 12-month follow-up, the lens remained clear
[Maculopathy in case of the pit of the disc].
Kolár, P
2005-09-01
The pit of the disc is a congenital anomaly of the optic nerve disc. The prevalence is 1/11 000 patients. On the affected side, the optic disc is in 85% of cases larger than the disc of the other healthy eye. The pit of the disc is very often associated with the presence of the cilioretinal artery. Maculopathy in congenital pit of the optic nerve disc was described in the early 30's of the last century by Calhoun. The average age of the patients is roughly 30 years of age (20-40 years). The complementary examination method, which may help to clarify anatomical conditions of the macular region, is the optical coherence tomography. The defect of the optic disc of different depth caused by the pit and maculopathy caused by retinoschisis communicating with the temporal rim of the disc are found. This case report refers to a 29 years old man with disturbing relative central scotoma and decreased vision for one month in his right eye, who underwent classical three-ports pars plana vitrectomy with expansive gas tamponade. On the basis of differential diagnosis discretion, the temporally localized pit of the disc accompanied by maculopathy due to retonoschisis was detemined. The surgical treatment by means of three-ports pars plana vitrectomy and peeling of the inner limiting membrane with expansive gas tamponade restored in our patient the physiological macular structure followed by improvement of the best-corrected visual acuity. No complications were noticed during the surgery or after it as well. Among the differential diagnoses, it is necessary to eliminate other possible causes of maculopathy in young patients as well as other congenital anomalies of the optic disc, which may be related to the maculopathy. Maculopathy following the pit of the optic nerve disc represents relatively rare diagnostic entity. According to the literature, the natural course of this disease results in very low final best-corrected visual acuity, often worse than 5/50 (0,1 or 20/200). The therapeutic possibility for patients with this disease is operative approach by means of pars plana vitrectomy with peeling of the inner limiting membrane and accompanied by expansive gas tamponade as already mentioned in our case report.
Liu, Xing; Li, Mei; Cheng, Bing; Mao, Zhen; Zhong, Yimin; Wang, Dandan; Cao, Dan; Yu, Fenfen; Congdon, Nathan G
2013-11-01
To describe sequential phacoemulsification-intraocular lens (IOL) implantation-posterior capsulorhexis-anterior vitrectomy in the management of phakic malignant glaucoma. Twenty consecutive patients (25 eyes) with phakic malignant glaucoma were enrolled at the Zhongshan Ophthalmic Center, Sun Yat-sen University. All patients underwent phacoemulsification, IOL implantation and posterior capsulorhexis together with anterior vitrectomy via a clear corneal paracentesis. Visual acuity, intraocular pressure (IOP), anterior chamber depth (ACD), surgical complications and medications required after the surgery were recorded. After surgery, the mean LogMAR visual acuity and ACD increased significantly (visual acuity from -1.56 ± 1.17 to -0.54 ± 0.81, p < 0.001; ACD from 0.367 ± 0.397 mm to 2.390 ± 0.575 mm, p < 0.001), and mean IOP decreased significantly (from 39.6 ± 10.6 mm Hg to 14.5 ± 4.1 mmHg, p < 0.001). No serious perioperative complications occurred, and only five eyes required topical glaucoma medications after surgery. Combined phacoemulsification-IOL implantation-posterior capsulorhexis-anterior vitrectomy surgery is a safe and effective method for treating patients with phakic malignant glaucoma. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.
Videoendoscopic Single-Port Nipple-Sparing Mastectomy and Immediate Reconstruction
Ozden, Burcu Celet; Agcaoglu, Orhan; Kecer, Mustafa; Ozmen, Vahit; Muslumanoglu, Mahmut; Igci, Abdullah
2014-01-01
Abstract Purpose: Single-incision videoendoscopic surgery has recently become popular as a result of the ongoing search for less invasive procedures. The aim of this study was to evaluate the safety and efficacy of endoscopic single-port nipple-sparing mastectomy, axillary lymphadenectomy, and immediate reconstruction in patients with breast cancer. Patients and Methods: From May 14, 2012 through January 23, 2013, 10 patients underwent videoendoscopic single-port nipple-sparing mastectomy and axillary dissection via a single, limited incision and immediate prosthetic reconstruction. Patient charts were reviewed, and demographic data, operative time, complications and pathology results were analyzed. Results: In all patients, videoendoscopic surgery was performed successfully. Of 10 patients, 7 were diagnosed as having invasive ductal carcinoma, 2 had a ductal carcinoma in situ, and 1 underwent bilateral prophylactic mastectomy. The weight of the resected gland was 300–650 g, with a mean of 420 g. There were no operative complications, and the mean operative time was 250 minutes (range, 160–330 minutes). One-stage reconstruction with implants was performed on 4 patients, whereas expanders were placed in the remaining 6. Surgical margins of all cases were pathologically negative, and there were no recurrences observed during the early follow-up period. Conclusions: Videoendoscopic single-port nipple-sparing mastectomy is technically feasible even in larger breasts, enabling immediate reconstruction with good cosmetic outcomes. However, further studies with larger clinical series and long-term follow-up are required to compare the safety and efficacy of the technique with those of the standard nipple-sparing mastectomy. PMID:24401140
Dhoble, Pankaja; Khodifad, Ashish
2018-01-01
To study the outcomes of combined cataract extraction with pars plana vitrectomy (PPV) and metallic intraocular foreign body (IOFB) removal through a sclerocorneal tunnel using the "magnetic handshake" technique. A retrospective review. Retrospective review of case records of 14 patients from 2010 to 2016 with metallic IOFB and traumatic cataract was performed. Cataract extraction was combined with PPV. Two intraocular magnets (IOMs) introduced through 20-gauge vitrectomy port and sclerocorneal tunnel helped achieve safe delivery of IOFB outside the globe by the "magnetic handshake" technique. All patients were males with a mean age of 33.04 years. A final best corrected visual acuity (BCVA) of 20/60 or better was noted in 10 (71.42%) of 14 patients. Final reattachment with more than 1 surgery was achieved in 13 (92.85%) patients. Postoperative complications included retinal detachment (RD) and phthisis bulbi in 1 (14.28%) patient each. Combined cataract extraction with PPV and metallic IOFB removal through sclerocorneal tunnel using the "magnet handshake" technique gives good visual and surgical outcomes. Copyright 2017 Asia-Pacific Academy of Ophthalmology.
Krueger, Ronald R; Uy, Harvey; McDonald, Jared; Edwards, Keith
2012-12-01
To demonstrate that ultrashort-pulse laser treatment in the crystalline lens does not form a focal, progressive, or vision-threatening cataract. An Nd:vanadate picosecond laser (10 ps) with prototype delivery system was used. Primates: 11 rhesus monkey eyes were prospectively treated at the University of Wisconsin (energy 25-45 μJ/pulse and 2.0-11.3M pulses per lens). Analysis of lens clarity and fundus imaging was assessed postoperatively for up to 4½ years (5 eyes). Humans: 80 presbyopic patients were prospectively treated in one eye at the Asian Eye Institute in the Philippines (energy 10 μJ/pulse and 0.45-1.45M pulses per lens). Analysis of lens clarity, best-corrected visual acuity, and subjective symptoms was performed at 1 month, prior to elective lens extraction. Bubbles were immediately seen, with resolution within the first 24 to 48 hours. Afterwards, the laser pattern could be seen with faint, noncoalescing, pinpoint micro-opacities in both primate and human eyes. In primates, long-term follow-up at 4½ years showed no focal or progressive cataract, except in 2 eyes with preexisting cataract. In humans, <25% of patients with central sparing (0.75 and 1.0 mm radius) lost 2 or more lines of best spectacle-corrected visual acuity at 1 month, and >70% reported acceptable or better distance vision and no or mild symptoms. Meanwhile, >70% without sparing (0 and 0.5 mm radius) lost 2 or more lines, and most reported poor or severe vision and symptoms. Focal, progressive, and vision-threatening cataracts can be avoided by lowering the laser energy, avoiding prior cataract, and sparing the center of the lens.
Krueger, Ronald R.; Uy, Harvey; McDonald, Jared; Edwards, Keith
2012-01-01
Purpose: To demonstrate that ultrashort-pulse laser treatment in the crystalline lens does not form a focal, progressive, or vision-threatening cataract. Methods: An Nd:vanadate picosecond laser (10 ps) with prototype delivery system was used. Primates: 11 rhesus monkey eyes were prospectively treated at the University of Wisconsin (energy 25–45 μJ/pulse and 2.0–11.3M pulses per lens). Analysis of lens clarity and fundus imaging was assessed postoperatively for up to 4½ years (5 eyes). Humans: 80 presbyopic patients were prospectively treated in one eye at the Asian Eye Institute in the Philippines (energy 10 μJ/pulse and 0.45–1.45M pulses per lens). Analysis of lens clarity, best-corrected visual acuity, and subjective symptoms was performed at 1 month, prior to elective lens extraction. Results: Bubbles were immediately seen, with resolution within the first 24 to 48 hours. Afterwards, the laser pattern could be seen with faint, noncoalescing, pinpoint micro-opacities in both primate and human eyes. In primates, long-term follow-up at 4½ years showed no focal or progressive cataract, except in 2 eyes with preexisting cataract. In humans, <25% of patients with central sparing (0.75 and 1.0 mm radius) lost 2 or more lines of best spectacle-corrected visual acuity at 1 month, and >70% reported acceptable or better distance vision and no or mild symptoms. Meanwhile, >70% without sparing (0 and 0.5 mm radius) lost 2 or more lines, and most reported poor or severe vision and symptoms. Conclusions: Focal, progressive, and vision-threatening cataracts can be avoided by lowering the laser energy, avoiding prior cataract, and sparing the center of the lens. PMID:23818739
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rudoltz, Marc S.; Ayyangar, Komanduri; Mohiuddin, Mohammed
Radiotherapy for lymphoma of the orbit must be individualized for each patient and clinical setting. Most techniques focus on optimizing the dose to the tumor while sparing the lens. This study describes a technique utilizing magnetic resonance imaging (MRI) and three dimensional (3D) planning in the treatment of orbital lymphoma. A patient presented with an intermediate grade lymphoma of the right orbit. The prescribed tumor dose was 4050 cGy in 18 fractions. Three D planning was carried out and tumor volumes, retina, and lens were subsequently outlined. Dose calculations including dose volume histograms of the target, retina, and lens weremore » then performed. Part of the retina was outside of the treatment volume while 50% of the retina received 90% or more of the prescribed dose. The patient was clinically NED when last seen 2 years following therapy with no treatment-related morbidity. Patients with lymphomas of the orbit can be optimally treated using MRI based 3D treatment planning.« less
Mardelli, Pierre G; Mardelli, Marc E
2018-04-01
We present a case of persistent aqueous misdirection, after Ahmed glaucoma valve surgery, despite undergoing an anterior vitrectomy with hyaloido-zonulectomy and iridectomy. A 73-year-old female patient, 4 months after phacotrabeculectomy, was referred with persistent high intraocular pressure (IOP). Postoperatively, she developed aqueous misdirection with a flat anterior chamber (AC) but with an IOP of 15 mm Hg. On presentation, her AC was shallow with peripheral iris-cornea touch, and her IOP was 39 mm Hg. Posterior Nd:Yag capsulotomy with disruption of anterior hyaloid face partially deepened the AC. With failure of the trabeculectomy and high IOP, an Ahmed valve was placed. On the first operative day the AC was deep with an IOP of 10 mm Hg. On day 6 the patient presented with pain, flat AC, and an IOP of 10 mm Hg. Fundus examination revealed no choroidal effusion. Despite repeated reformation with viscoelastic, the AC failed to deepen. An anterior vitrectomy with hyaloido-zonulectomy was performed. Initially, the AC was deep, but, a few days later, it was flat. Multiple reformations and vitreous tap failed to keep the AC deep. A 30-G needle was passed at the slit lamp across the temporal cornea, iris, and anterior capsule into the anterior vitreous cavity. The needle was then partially withdrawn and used to create a space between the intraocular lens and anterior capsule. This immediately deepened the AC and remained so for the duration of follow-up (4 mo). Slit-lamp needling of the anterior lens capsule can be successfully performed to help resolve a persistent case of aqueous misdirection after anterior vitrectomy.
Efficient Switching Arrangement for (N + 1)/N Redundancy
NASA Technical Reports Server (NTRS)
Lux, James; McMaster, Robert
2007-01-01
An efficient arrangement of four switches has been conceived for coupling, to four output ports, the output powers of any subset of four devices that are members of a redundant set of five devices. In normal operation, the output power of each of four of the devices would be coupled to one of the four output ports. The remaining device would be kept as a spare: normally, its output power would be coupled to a load, wherein that power would be dissipated. In the event of failure of one of the four normally used devices, that device would be disconnected from its output port and connected to the load, and the spare device would be connected to the output from which the failed device was disconnected. Alternatively or in addition, the outputs of one or more devices could be sent to ports other than the ones originally assigned to them.
Vanner, Elizabeth A; Stewart, Michael W
2014-01-01
Purpose/design We aimed to perform a systematic review and meta-analysis comparing the risk difference of clinical outcomes for same-day (SD) vs delayed (DEL) pars plana vitrectomy (PPV). Methods We searched MEDLINE (English; January 1, 1985 to July 16, 2013) and article reference lists, for patients with crystalline retained lens fragments and discussion of SD-PPV vs DEL-PPV. For the meta-analysis, articles needed the number of patients receiving SD-PPV and DEL-PPV, and the number, in each group, who experienced one or more of the outcomes: not good visual acuity (VA) (<20/40), bad VA (≤20/200), retinal detachment, increased intraocular pressure/glaucoma, intraocular infection/inflammation, cystoid macular edema, and corneal edema. Results Of 304 articles identified, 23 provided data for the meta-analysis. Results were mixed, indicating 1) neither vitrectomy time produced better outcomes in all studies (not good VA risk difference =10.3% [positive numbers favored SD-PPV; negative numbers favored DEL-PPV], 95% confidence interval [CI] = [−0.4% to 21.0%], P=0.059; and bad VA risk difference =−0.3%, 95% CI = [−10.7% to 10.1%], P=0.953); 2) better outcomes with immediate SD-PPV compared with all DEL-PPV (not good VA risk difference =16.2%, 95% CI = [0.8% to 31.5%], P=0.039; and bad VA risk difference =8.5%; 95% CI = [0.8% to 16.2%], P=0.030); and 3) immediate SD-PPV and prompt DEL-PPV (3 to 14 days after cataract surgery) had no significant differences and so may produce similar outcomes (not good VA risk differences range = [−19.9% to 6.5%], 95% CI = [−59.9% to 36.4%]; and bad VA risk differences range = [−6.9% to 7.4%], 95% CI = [−33.1% to 31.8%]). Conclusion Perhaps SD-PPV should be limited to facilities at which a vitreoretinal surgeon is immediately available. Otherwise, these results support referring a patient with retained lens fragments promptly to a vitreoretinal surgeon but do not support interfacility transport for SD-PPV. PMID:25429196
Building 904, oblique view to southeast, 135 mm lens. ...
Building 904, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA
Building 904, oblique view to northwest, 135 mm lens ...
Building 904, oblique view to northwest, 135 mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA
Comparison of clinical outcome between 23-G and 25-G vitrectomy in diabetic patients
Taleb, Eman Abo; Nagpal, Manish P.; Mehrotra, Navneet S.; Bhatt, Kalyani; Goswami, Sangeeta; Babalola, Yewande O.; Noman, Abdulrahman
2017-01-01
PURPOSE: To compare the clinical outcomes and complications between 23-G and 25-G vitrectomy in patients with diabetic vitreous hemorrhage (VH). MATERIALS AND METHODS: A retrospective comparative study comprising 69 eyes (36 eyes in 23-G group and 33 eyes in 25-G group) of 65 patients who underwent vitrectomy with air tamponade for diabetic vitreous hemorrhage (VH) with at least 6 months of follow-up was conducted. RESULTS: There were no significant differences between the two groups in age, gender, bilaterality, type of diabetes, presence of hypertension, lens status, and previous argon laser photocoagulation state (P > 0.05). Best-corrected visual acuity (BCVA) of both groups at postoperative 1 month logarithm of the minimum angle of resolution (logMAR) (1.06 ± 0.99, 0.90 ± 0.96), 3 months logMAR (1.07 ± 0.93, 0.83 ± 0.85), and 6 months logMAR (1.03 ± 0.89, 0.83 ± 0.85) significantly improved from the preoperative BCVA logMAR (2.03 ± 0.83, 2.15 ± 0.99) for 23-G group, 25-G group, respectively (P < 0.0001). There was no significant difference in BCVA between the two groups preoperatively and at 1, 3, and 6 months postoperatively (P = 0.566, 0.506, 0.333, and 0.445, respectively), incidence of intraoperative wound suturing (21.4%, 15.2%), postoperative hypotony (0.0%, 0.0%), early postoperative VH (POVH) (11.1%, 15.2%), late POVH (5.6%, 0.0%), retinal detachment (2.8%, 6.1%), neovascular glaucoma (92.8%, 9.1%), and endophthalmitis (0.0%, 0.0%) for 23-G group, 25-G group, respectively (P > 0.05). CONCLUSION: 25-G vitrectomy is as effective for PDR as 23-G vitrectomy. PMID:29118498
Comparison of clinical outcome between 23-G and 25-G vitrectomy in diabetic patients.
Taleb, Eman Abo; Nagpal, Manish P; Mehrotra, Navneet S; Bhatt, Kalyani; Goswami, Sangeeta; Babalola, Yewande O; Noman, Abdulrahman
2017-01-01
To compare the clinical outcomes and complications between 23-G and 25-G vitrectomy in patients with diabetic vitreous hemorrhage (VH). A retrospective comparative study comprising 69 eyes (36 eyes in 23-G group and 33 eyes in 25-G group) of 65 patients who underwent vitrectomy with air tamponade for diabetic vitreous hemorrhage (VH) with at least 6 months of follow-up was conducted. There were no significant differences between the two groups in age, gender, bilaterality, type of diabetes, presence of hypertension, lens status, and previous argon laser photocoagulation state ( P > 0.05). Best-corrected visual acuity (BCVA) of both groups at postoperative 1 month logarithm of the minimum angle of resolution (logMAR) (1.06 ± 0.99, 0.90 ± 0.96), 3 months logMAR (1.07 ± 0.93, 0.83 ± 0.85), and 6 months logMAR (1.03 ± 0.89, 0.83 ± 0.85) significantly improved from the preoperative BCVA logMAR (2.03 ± 0.83, 2.15 ± 0.99) for 23-G group, 25-G group, respectively ( P < 0.0001). There was no significant difference in BCVA between the two groups preoperatively and at 1, 3, and 6 months postoperatively ( P = 0.566, 0.506, 0.333, and 0.445, respectively), incidence of intraoperative wound suturing (21.4%, 15.2%), postoperative hypotony (0.0%, 0.0%), early postoperative VH (POVH) (11.1%, 15.2%), late POVH (5.6%, 0.0%), retinal detachment (2.8%, 6.1%), neovascular glaucoma (92.8%, 9.1%), and endophthalmitis (0.0%, 0.0%) for 23-G group, 25-G group, respectively ( P > 0.05). 25-G vitrectomy is as effective for PDR as 23-G vitrectomy.
Citirik, Mehmet; Batman, Cosar; Bicer, Tolga; Zilelioglu, Orhan
2009-09-01
To assess the alterations in keratometric astigmatism following the 25-gauge transconjunctival sutureless pars plana vitrectomy versus the conventional pars plana vitrectomy. Sixteen consecutive patients were enrolled into the study. Conventional vitrectomy was applied to eight of the cases and 25-gauge transconjunctival sutureless vitrectomy was performed in eight patients. Keratometry was performed before and after the surgery. In the 25-gauge transconjunctival sutureless pars plana vitrectomy group, statistically significant changes were not observed in the corneal curvature in any post-operative follow-up measurement (p > 0.05); whereas in the conventional pars plana vitrectomy group, statistically significant changes were observed in the first postoperative day (p = 0.01) and first postoperative month (p = 0.03). We noted that these changes returned to baseline in three months (p = 0.26). Both 25-gauge transconjunctival sutureless and conventional pars plana vitrectomy are effective surgical modalities for selected diseases of the posterior segment. Surgical procedures are critical for the visual rehabilitation of the patients. The post-operative corneal astigmatism of the vitrectomised eyes can be accurately determined at least two months post-operatively.
Scleral fixation of foldable acrylic intraocular lenses in aphakic post-vitrectomy eyes
Mutoh, Tetsuya; Matsumoto, Yukihiro; Chikuda, Makoto
2011-01-01
Purpose To evaluate the outcome for scleral fixation of a foldable acrylic intraocular lens (IOL) in aphakic post-pars plana vitrectomy eyes for vitreoretinal disease. Methods The medical records of 15 patients were reviewed. We evaluated such factors as the underlying vitreoretinal disease, preoperative expected refraction and postoperative actual refraction, best corrected visual acuity (BCVA), corneal endothelial cell density, and intraoperative and postoperative complications. Results The most common cause of underlying vitreoretinal disease was retinal detachment, which was found in 8 cases. The mean refractive error was −0.10 diopters (D). The mean minimum angle of resolution (logMAR) values of BCVA were 0.27 preoperatively and 0.14 postoperatively. The mean corneal endothelial cell density was 2400 cells/mm2 preoperatively and 2187 cells/mm2 postoperatively. No significant differences were observed in either the logMAR values of BCVA or the corneal endothelial cell density before and after surgery. No intraoperative complications occurred in any of the patients. Postoperative complications occurred in a total of 7 eyes, and the most severe complications comprised 4 cases of transient ocular hypertension. Conclusion The results for the scleral fixation of foldable acrylic IOLs were good in aphakic post-vitrectomy eyes. PMID:21311652
Short-term in vivo evaluation of novel vital dyes for intraocular surgery.
Haritoglou, Christos; Tadayoni, Ramin; May, Christian A; Gass, Carolin A; Freyer, Wolfgang; Priglinger, Siegfried G; Kampik, Anselm
2006-01-01
To evaluate the staining characteristics and safety of potential new dyes for intraocular surgery in porcine eyes. Four dyes in different solutions (light green SF yellowish [LGSF]: 2%; copper(II) phthalocyanine-tetrasulfonic acid [E68]: 2% and 0.5%; bromophenol blue [BPB]: 2%, 1%, and 0.2%; and Chicago blue [CB]: 2% and 0.5%) were included in this investigation. All dyes were dissolved and diluted using balanced salt solution (BSS plus; Alcon Laboratories, Inc., Fort Worth, TX). After triamcinolone-assisted vitrectomy on 10 porcine eyes in vivo, the dyes were first injected into the air-filled vitreous cavity. After 1 minute, the dye was removed by irrigation with BSS, and the staining effect was graded by two examiners. After vitrectomy, the same dyes and concentrations were injected in the air-filled anterior chamber to stain the lens capsule of the same eye. After surgery, the eyes were enucleated and underwent fixation for light and electron microscopy. The animals were killed by injection of pentobarbital (50 mg/kg). For controls, each BSS plus alone and indocyanine green 0.5% were applied in one eye. On the retinal surface, bright staining of the retinal surface was seen after application of BPB 2% and 1%. The staining effect was less pronounced but still very good using E68 2%, and CB 2% and weak using BPB 0.2%, E68 0.5% and CB 0.5% as well as indocyanine green 0.5%. No staining of the retinal surface but of the vitreous was seen after application of LGSF 2%. The lens capsule stained very well with E68 2%, CB 2% and 0.5%, and BPB 2%, 1%, and 0.2% but not with LGSF. No histologic abnormalities were seen after the application in any eye after dye injection. No dye-related complications occurred during surgery. In this study, we identified three dyes with satisfying staining characteristics in both anterior and posterior segments. Because BPB stained the retinal surface and lens capsule at a low concentration (0.2%) with no signs of toxicity, this dye seems to be the most promising candidate for application in humans.
Le Rouic, J-F; Ducournau, D; Becquet, F
2006-09-01
To report the use of triamcinolone-assisted vitrectomy to assess the cause of vitrectomy failure in the treatment of retinal detachment due to myopic macular hole. We report the cases of three myopic patients presenting with recurrent retinal detachment due to macular hole after initial vitrectomy treatment with posterior vitreous detachment, a systematic attempt at membrane peeling, and gas injection (SF6). No retinal traction or tear other than the macular hole was observed. The recurrence of retinal detachment was treated with vitrectomy and intraoperative use of triamcinolone, which demonstrated persistent posterior hyaloid and thin and strongly adherent membrane remnants in each case. Anatomic success was obtained after peeling these structures. Intraoperative use of triamcinolone reduces the risk of overlooking hyaloid or membrane remnants during vitrectomy for the treatment of myopic retinal detachment. Transparent remnants of posterior hyaloid and membranes were visualized by triamcinolone-assisted vitrectomy. They could lead to traction on the retina and explain the failure of the initial vitrectomy. Anatomic success was obtained after peeling these structures.
Asian society of gynecologic oncology workshop 2010
Suh, Dong Hoon; Kim, Jae Weon; Aziz, Mohamad Farid; Devi, Uma K.; Ngan, Hextan Y. S.; Nam, Joo-Hyun; Kim, Seung Cheol; Kato, Tomoyasu; Ryu, Hee Sug; Fujii, Shingo; Lee, Yoon Soon; Kim, Jong Hyeok; Kim, Tae-Joong; Kim, Young Tae; Wang, Kung-Liahng; Lee, Taek Sang; Ushijima, Kimio; Shin, Sang-Goo; Chia, Yin Nin; Wilailak, Sarikapan; Park, Sang Yoon; Katabuchi, Hidetaka; Kamura, Toshiharu
2010-01-01
This workshop was held on July 31-August 1, 2010 and was organized to promote the academic environment and to enhance the communication among Asian countries prior to the 2nd biennial meeting of Australian Society of Gynaecologic Oncologists (ASGO), which will be held on November 3-5, 2011. We summarized the whole contents presented at the workshop. Regarding cervical cancer screening in Asia, particularly in low resource settings, and an update on human papillomavirus (HPV) vaccination was described for prevention and radical surgery overview, fertility sparing and less radical surgery, nerve sparing radical surgery and primary chemoradiotherapy in locally advanced cervical cancer, were discussed for management. As to surgical techniques, nerve sparing radical hysterectomy, optimal staging in early ovarian cancer, laparoscopic radical hysterectomy, one-port surgery and robotic surgery were introduced. After three topics of endometrial cancer, laparoscopic surgery versus open surgery, role of lymphadenectomy and fertility sparing treatment, there was a special additional time for clinical trials in Asia. Finally, chemotherapy including neo-adjuvant chemotherapy, optimal surgical management, and the basis of targeted therapy in ovarian cancer were presented. PMID:20922136
27-Gauge Vitrectomy for Symptomatic Vitreous Floaters with Topical Anesthesia
Lin, Zhong; Moonasar, Nived; Wu, Rong Han; Seemongal-Dass, Robin R.
2017-01-01
Purpose Traditionally acceptable methods of anesthesia for vitrectomy surgery are quite varied. However, each of these methods has its own potential for complications that can range from minor to severe. The surgery procedure of vitrectomy for symptomatic vitreous floaters is much simpler, mainly reflecting in the nonuse of sclera indentation, photocoagulation, and the apparently short surgery duration. The use of 27-gauge cannulae makes the puncture of the sclera minimally invasive. Hence, retrobulbar anesthesia, due to its rare but severe complications, seemed excessive for this kind of surgery. Method Three cases of 27-gauge, sutureless pars plana vitrectomy for symptomatic vitreous floaters with topical anesthesia are reported. Results The vitrectomy surgeries were successfully performed with topical anesthesia (proparacaine, 0.5%) without operative or postoperative complications. Furthermore, none of the patients experienced apparent pain during or after the surgery. Conclusion Topical anesthesia can be considered for 27-guage vitrectomy in patients with symptomatic vitreous floaters. PMID:28203195
27-Gauge Vitrectomy for Symptomatic Vitreous Floaters with Topical Anesthesia.
Lin, Zhong; Moonasar, Nived; Wu, Rong Han; Seemongal-Dass, Robin R
2017-01-01
Traditionally acceptable methods of anesthesia for vitrectomy surgery are quite varied. However, each of these methods has its own potential for complications that can range from minor to severe. The surgery procedure of vitrectomy for symptomatic vitreous floaters is much simpler, mainly reflecting in the nonuse of sclera indentation, photocoagulation, and the apparently short surgery duration. The use of 27-gauge cannulae makes the puncture of the sclera minimally invasive. Hence, retrobulbar anesthesia, due to its rare but severe complications, seemed excessive for this kind of surgery. Three cases of 27-gauge, sutureless pars plana vitrectomy for symptomatic vitreous floaters with topical anesthesia are reported. The vitrectomy surgeries were successfully performed with topical anesthesia (proparacaine, 0.5%) without operative or postoperative complications. Furthermore, none of the patients experienced apparent pain during or after the surgery. Topical anesthesia can be considered for 27-guage vitrectomy in patients with symptomatic vitreous floaters.
Panek, Wojciech; Lewandowski, Jaroslaw; Tuchendler, Tomasz; Urbańczyk, Grzegorz; Litarski, Adam; Apoznański, Wojciech
2013-01-01
The aim of the study was to describe simultaneous laparoscopic adrenalectomy and laparoscopic nephron-sparing surgery, to discuss the details of a convenient laparoscopic approach and the way of port placement, as well as to present a review of the literature concerning combined laparoscopic procedures. A 72-year-old woman was admitted to our department because of a tumor of the right adrenal gland and a small tumor of the right kidney. The patient underwent simultaneous laparoscopic adrenalectomy and laparoscopic nephron-sparing surgery. The postoperative period was uncomplicated. The patient was discharged from the hospital on the 4th postoperative day. We believe that the proposed way of trocar placement would help to avoid a ‘rollover’ problem between the laparoscope and a Satinsky clamp or a ‘crossing swords’ problem between a Satinsky clamp and manipulators. PMID:24501608
Clinically undetected retinal breaks causing retinal detachment: A review of options for management.
Gupta, Deepak; Ching, Jared; Tornambe, Paul E
2017-08-12
The successful detection of retinal breaks is a critical step in rhegmatogenous retinal detachment surgery in order to prevent persistent/recurrent retinal detachments. Not all retinal breaks causing retinal detachments are obvious. Retinal breaks may be obscured by opacities that are either anterior segment related, lens related, or posterior segment related. Rules to identify breaks based on subretinal fluid configuration are more difficult to apply in pseudophakic, aphakic, and scleral buckle encircled eyes-and in eyes with repeat detachments and those with proliferative vitreoretinopathy. Exudative detachments exhibit characteristic features and must be ruled out. A thorough clinical examination preoperatively is important even if a vitrectomy is planned. We review the incidence and causes of undetected breaks, along with preoperative/clinical issues that may hinder break detection. We review the literature with respect to investigative approaches and techniques that are available to the vitreoretinal surgeon when primary breaks remain clinically undetected during the preoperative examination. We broadly divide the surgical approaches into ones where the surgeon utilizes techniques to pursue actively a search for breaks versus adopting a purely speculative approach. Advantages and disadvantages of various techniques are appraised. Intuitively one might argue that an encircling scleral buckle combined with vitrectomy would give higher single operation success than pars plana vitrectomy alone because "undetected" retinal breaks would be addressed by a 360° plombage. We could not confirm this concept. Newer techniques, such as pars plana vitrectomy augmented with dye extrusion or endoscopic-assisted pars plana vitrectomy, show encouraging results. Technological advances such as intraoperative optical coherence tomography will also help to broaden the vitreoretinal surgeon's armamentarium. At this time, there is no gold standard in terms of the recommended approach, and this is reflected in the many options that are available for management. The surgeon must consider the benefits versus the risk of their preferred approach. Copyright © 2017 Elsevier Inc. All rights reserved.
Supine craniospinal irradiation in pediatric patients by proton pencil beam scanning.
Farace, Paolo; Bizzocchi, Nicola; Righetto, Roberto; Fellin, Francesco; Fracchiolla, Francesco; Lorentini, Stefano; Widesott, Lamberto; Algranati, Carlo; Rombi, Barbara; Vennarini, Sabina; Amichetti, Maurizio; Schwarz, Marco
2017-04-01
Proton therapy is the emerging treatment modality for craniospinal irradiation (CSI) in pediatric patients. Herein, special methods adopted for CSI at proton Therapy Center of Trento by pencil beam scanning (PBS) are comprehensively described. Twelve pediatric patients were treated by proton PBS using two/three isocenters. Special methods refer to: (i) patient positioning in supine position on immobilization devices crossed by the beams; (ii) planning field-junctions via the ancillary-beam technique; (iii) achieving lens-sparing by three-beams whole-brain-irradiation; (iv) applying a movable-snout and beam-splitting technique to reduce the lateral penumbra. Patient-specific quality assurance (QA) program was performed using two-dimensional ion chamber array and γ-analysis. Daily kilovoltage alignment was performed. PBS allowed to obtain optimal target coverage (mean D98%>98%) with reduced dose to organs-at-risk. Lens sparing was obtained (mean D1∼730cGyE). Reducing lateral penumbra decreased the dose to the kidneys (mean Dmean<600cGyE). After kilovoltage alignment, potential dose deviations in the upper and lower junctions were small (average 0.8% and 1.2% respectively). Due to imperfect modeling of range shifter, QA showed better agreements between measurements and calculations at depths >4cm (mean γ>95%) than at depths<4cm. The reported methods allowed to effectively perform proton PBS CSI. Copyright © 2017 Elsevier B.V. All rights reserved.
Performance analysis of a new hypersonic vitrector system.
Stanga, Paulo Eduardo; Pastor-Idoate, Salvador; Zambrano, Isaac; Carlin, Paul; McLeod, David
2017-01-01
To evaluate porcine vitreous flow and water flow rates in a new prototype hypersonic vitrectomy system compared to currently available pneumatic guillotine vitrectors (GVs) systems. Two vitrectors were tested, a prototype, ultrasound-powered, hypersonic vitrector (HV) and a GV. Porcine vitreous was obtained within 12 to 24 h of sacrifice and kept at 4°C. A vial of vitreous or water was placed on a precision balance and its weight measured before and after the use of each vitrector. Test parameters included changes in aspiration levels, vitrector gauge, cut rates for GVs, % ultrasound (US) power for HVs, and port size for HVs. Data was analysed using linear regression and t-tests. There was no difference in the total average mean water flow between the 25-gauge GV and the 25-gauge HV (t-test: P = 0.363); however, 25-gauge GV was superior (t-test: P < 0.001) in vitreous flow. The 23-gauge GV was only more efficient in water and vitreous removal than 23-gauge HV needle-1 (Port 0.0055) (t-test: P < 0.001). For HV, wall thickness and gauge had no effect on flow rates. Water and vitreous flows showed a direct correlation with increasing aspiration levels and % US power (p<0.05). The HV produced consistent water and vitreous flow rates across the range of US power and aspiration levels tested. Hypersonic vitrectomy may be a promising new alternative to the currently available guillotine-based technologies.
Management of nucleus loss into the vitreous: long term follow up in 63 patients
Romero-Aroca, Pedro; Fernández-Ballart, Juan; Méndez-Marín, Isabel; Salvat-Serra, Merce; Baget-Bernaldiz, Marc; Buil-Calvo, Jose A
2007-01-01
Background: The aim of present study is to determine the long-term results of patients who undergo pars plana vitrectomy after retained nucleus into the vitreous. Setting: Service of Ophthalmology, Hospital Universitari St Joan, Reus (Barcelona), Spain. Methods: Retrospective, noncomparative, consecutive case series. Medical records were reviewed of all patients who underwent pars plana vitrectomy for retained nucleus into the vitreous after complicated cataract surgery, over a 9-year period between August 1, 1997 and July 31, 2005. Result: The incidence of retained lens fragments was 0.57% (63 patients), the postoperative visual acuity was higher than 20/40 in 59.60% and fell to 48.93% by the end of the study, and was related to the presence of CME and retinal detachment. The CME appeared in 31.91% of the patients and was related to preoperative uveitis an corneal edema. In the group of patients on whom the vitrectomy was performed at the time of cataract complication, visual acuity was higher than 20/40 in 77.77%, and no one developed secondary glaucoma or uveitis. Conclusion: Being retrospective, our study was not result conclusive. Despite the initial good results of these patients after PPV surgery, follow-up should be accurate and over a long period of time in order to minimize postoperative complications such as retinal detachment, retinal breaks, secondary glaucoma and CME. PMID:19668529
2009-11-27
CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Atlantis is towed from the Shuttle Landing Facility to Orbiter Processing Facility-1, or OPF-1. Atlantis touched down on Runway 33 after 11 days in space, completing the 4.5-million mile STS-129 mission to the International Space Station on orbit 171. In OPF-1, processing will begin for Atlantis' next mission, designated STS-132. The 34th shuttle mission to the International Space Station, Atlantis will deliver an Integrated Cargo Carrier and Russian-built Mini Research Module, or MRM, to the orbiting laboratory on STS-132. The second in a series of new pressurized components for Russia, the MRM will be permanently attached to the bottom port of the Zarya module. The Russian module also will carry U.S. pressurized cargo. Three spacewalks are planned to stage spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-Purpose Laboratory Module also are payloads on the flight. Photo credit: NASA/Jack Pfaller
2009-11-27
CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Atlantis begins its slow trek from the Shuttle Landing Facility to Orbiter Processing Facility-1, or OPF-1. Atlantis touched down on Runway 33 after 11 days in space, completing the 4.5-million mile STS-129 mission to the International Space Station on orbit 171. In OPF-1, processing will begin for Atlantis' next mission, designated STS-132. The 34th shuttle mission to the International Space Station, Atlantis will deliver an Integrated Cargo Carrier and Russian-built Mini Research Module, or MRM, to the orbiting laboratory on STS-132. The second in a series of new pressurized components for Russia, the MRM will be permanently attached to the bottom port of the Zarya module. The Russian module also will carry U.S. pressurized cargo. Three spacewalks are planned to stage spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-Purpose Laboratory Module also are payloads on the flight. Photo credit: NASA/Jack Pfaller
2009-11-27
CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Atlantis arrives at Orbiter Processing Facility-1, or OPF-1. Atlantis touched down on Runway 33 at the Shuttle Landing Facility after 11 days in space, completing the 4.5-million mile STS-129 mission to the International Space Station on orbit 171. In OPF-1, processing will begin for its next mission, designated STS-132. The 34th shuttle mission to the International Space Station, Atlantis will deliver an Integrated Cargo Carrier and Russian-built Mini Research Module, or MRM, to the orbiting laboratory on STS-132. The second in a series of new pressurized components for Russia, the MRM will be permanently attached to the bottom port of the Zarya module. The Russian module also will carry U.S. pressurized cargo. Three spacewalks are planned to stage spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-Purpose Laboratory Module also are payloads on the flight. Photo credit: NASA/Jack Pfaller
2009-11-27
CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Atlantis arrives at Orbiter Processing Facility-1, or OPF-1. Atlantis touched down on Runway 33 at the Shuttle Landing Facility after 11 days in space, completing the 4.5-million mile STS-129 mission to the International Space Station on orbit 171. In OPF-1, processing will begin for its next mission, designated STS-132. The 34th shuttle mission to the International Space Station, Atlantis will deliver an Integrated Cargo Carrier and Russian-built Mini Research Module, or MRM, to the orbiting laboratory on STS-132. The second in a series of new pressurized components for Russia, the MRM will be permanently attached to the bottom port of the Zarya module. The Russian module also will carry U.S. pressurized cargo. Three spacewalks are planned to stage spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-Purpose Laboratory Module also are payloads on the flight. Photo credit: NASA/Jack Pfaller
Yonemoto, Yumiko; Morishita, Seita; Fukumoto, Masanori; Mimura, Masashi; Sato, Takaki; Kida, Teruyo; Kojima, Shota; Oku, Hidehiro; Sugasawa, Jun; Ikeda, Tsunehiko
2018-06-01
The aim of this study was to report a case of Down syndrome (DS) complicated with bilateral retinal detachment (RD) due to unusual retinal degeneration. A 9-year-old girl complained of bilateral visual disturbance during a follow-up examination for myopia and strabismus. Slit-lamp examination revealed moderate posterior subcapsular cataract in both eyes. B-mode echography showed bilateral bullous RD; however, it was difficult to detect the causal retinal breaks due to poor mydriasis. For treatment, the patient underwent bilateral lensectomy, vitrectomy, and silicone oil tamponade. Intraoperative findings revealed symmetrical retinal breaks and unusual caterpillar-like retinal degeneration on the upper temporal side of both eyes. Three months later, the patient underwent bilateral silicone oil removal and intraocular lens implantation. In this case, the retinal degeneration was morphologically different from retinal lattice degeneration, thus suggesting that it might be involved in the onset of DS-related bilateral RD.
18. Detail, typical quarryfaced ashlar blocks, convextooled mortar joints, on ...
18. Detail, typical quarry-faced ashlar blocks, convex-tooled mortar joints, on pillars in former porte porte cochere area, view to southeast, 135mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA
Aging and Age-Related Diseases of the Ocular Lens and Vitreous Body
Petrash, J. Mark
2013-01-01
Reduced quality of life and financial burden due to visual impairment and blindness begin to increase dramatically when individuals reach the age of 40. The major causes of age-related vision loss can be traced to changes to the structure and function of the lens, one of the tissues responsible for focusing light on the retina. Age-related nuclear cataracts, which are caused by aggregation and condensation of proteins, diminish vision because they impede the transmission and focusing of light on the retina. In addition to the slow-developing age-related form, cataracts often develop rapidly as a complication of ocular surgery, such as following vitrectomy or as a consequence of vitreous gel degeneration. Posterior capsular opacification, which can develop following cataract removal, is caused by proliferation and inappropriate accumulation of lens epithelial cells on the surfaces of intraocular lenses and the posterior lens capsule. Presbyopia is a loss of accommodative amplitude and reduced ability to shift focus from far to near objects. Onset of presbyopia is associated with an increase in lens hardness and reduced ability of the lens to change shape in response to ciliary muscle contraction. Avenues of promising research that seek to delay or prevent these causes of low vision are discussed in light of our current understanding of disease pathogenesis and some challenges that must be met to achieve success. PMID:24335070
Hirata, Akira; Hayashi, Ken; Murata, Kazuhisa; Nakamura, Kei-Ichiro
2018-03-01
The formation of macular hole after receiving anti-vascular endothelial growth factor (anti-VEGF) therapy is rare. We report a case of macular hole that occurred after intravitreal injection of an anti-VEGF agent for age-related macular degeneration (AMD) in a patient, who underwent vitrectomy combined with choroidal neovascularization (CNV) removal. A 64-year-old female with AMD affecting her right eye received an intravitreal injection of an anti-VEGF agent. After treatment, we identified a full thickness macular hole (MH) that was associated with the rapid resolution of the macular edema and contraction of the CNV. After performing vitrectomy combined with CNV removal, the MH closed and her visual acuity improved. Examination of the removed CNV revealed a network of microvessels devoid of pericytes. and Importance: The present findings suggest that rapid resolution of macular edema and contraction of the CNV and/or mild increase in the vitreous traction after anti-VEGF therapy could potentially cause MH. CNV removal via the MH may be an acceptable procedure, if the MH remains open, the CNV is of the classic type, and it spares a central portion of the fovea.
Bar-Sela, Shai M; Har-Noy, Nurit Birman; Spierer, Abraham
2014-08-01
To evaluate the risk factors for secondary membrane (SM) formation after congenital cataract surgery with intraocular lens (IOL) implantation. A retrospective non-interventional comparative study. Thirty-nine patients (63 eyes) aged 1-135 months. The study included patients who underwent cataract extraction and primary IOL implantation between 1994 and 2001 at the University Hospital. The postoperative follow-up was 6-24 months. Thirty-three eyes received a poly(methyl methacrylate) (PMMA) IOL without square edges, 29 eyes received a hydrophobic acrylic IOL with truncated square edges (AcrySof), and there was no data for IOL type in one eye. Thirty-nine eyes had primary posterior capsulotomy (PPC) and anterior vitrectomy (AV) and in 24 eyes the posterior capsule was left intact. Cox proportional hazard regression analysis was performed to identify significant risk factors for SM formation, and Wilcoxon test to evaluate the difference in time from surgery to SM formation. SM developed in 24 eyes (38 %)--58 % of eyes with an intact posterior capsule and 26 % of eyes having PPC and AV, 42 % of eyes with a PMMA IOL, and 34 % of eyes with an AcrySof lens. In multivariate Cox regression analysis intraoperative PPC and AV (P = 0.02) and AcrySof lens implantation (P = 0.097) were associated with decreased postoperative incidence of SM formation. Median time until SM development was 2.9 months with PMMA IOLs (range 1-17 months) and 6 months with AcrySof lenses (range 1-21.8 months) (P = 0.037). Posterior capsule management as well as IOL design and material influence the incidence and the timing of SM formation after primary IOL implantation in children.
Scott, Nathan L; Sridhar, Jayanth; Flynn, Harry W
2018-06-01
To describe the management of a giant retinal tear with retinal detachment in a patient with active toxoplasmosis retinochoroiditis. While receiving systemic medications for toxoplasmosis, the patient underwent scleral buckling, pars plana vitrectomy, and C3F8 gas tamponade without removal of the lens. At last follow-up, best corrected visual acuity was 20/20 with an attached retina and the toxoplasmosis lesion was inactive. and Importance: Using modern surgical techniques, anatomic and clinical success is possible during active retinochoroiditis.
Odell, Kelly R
2009-01-01
Historically, treatment for choroidal melanomas was surgical enucleation. Currently, treatment methods such as stereotactic radiosurgery and brachytherapy are being used to spare the eye. The poster "Dosimetric Comparison of Gamma Knife Radiosurgery vs. I-125 Plaque Brachytherapy in a Cohort of Choroidal Melanomas" presented at ASTRO 2007 by Anderson et al. provides a comparison of these methods. The dose to disk, fovea and lens in 29 patients from a simulated I-125 treatment and a delivered Gamma Knife radiosurgery was compared. Thirty Gy was prescribed to the 50% Isodose line in the radiosurgery and 85 Gy was prescribed to the apex of the tumor in the I-125 simulation. It was found that the Gamma Knife spares the disk better in 59% of the tumors, including those >or=6.5 mm in height; spares the fovea better in 69% of the tumors, including those >or=5.5 mm; and spares lens better in only 30% of the tumors, with no distinction in size. Tumor location was not taken into account for this study, which could explain the variations in smaller tumors. For larger tumors, gamma knife will protect most organs at risk more effectively. This study shows how a tumor's parameters can be used in selecting treatment modality.
Surgical management of malignant glaucoma: a retrospective analysis of fifty eight eyes.
Balekudaru, S; Choudhari, N S; Rewri, P; George, R; Bhende, P S; Bhende, M; Lingam, V; Lingam, G
2017-06-01
PurposeTo assess outcomes of surgical management of malignant glaucoma in terms of re-formation of anterior chamberMethodsThis was a retrospective analysis of consecutive patients who underwent surgical treatment for malignant glaucoma between January 1995 and December 2013 at a tertiary care ophthalmic institute, with a minimum follow up of 2 months.ResultsFifty eight eyes of 58 patients were included. Fifty two (89.7%) patients had primary angle closure glaucoma. The majority had undergone glaucoma filtration surgery earlier (n=53, 91.4%). Lensectomy and anterior vitrectomy was performed in 15 (25.9%) eyes (Group 1). Vitrectomy and anterior chamber re-formation was performed in 27 (46.6%) eyes (Group 2). Vitrectomy-phacoemulsification-vitrectomy was performed in 16 (27.6%) eyes (Group 3). Communication between the two segments of eye through anterior hyaloid, lens capsule complex and/or iris was achieved in all groups. The median follow-up (Inter-quartile range) was 30 (71.5) months. Anterior chamber re-formation was achieved in 56 (96.5%) eyes at final visit. The improvement in mean±SD LogMAR visual acuity (1.1±1 to 0.7±0.8) and reduction in number ±SD of anti-glaucoma medications (2.1±1.1 to 1±1.6) between onset and final visit were significant (P=0.02 and <0.01, respectively). The intraocular pressure (mm Hg) at onset and at final visit was 30.7±17.4 and 14±6.2, 32.8±12.6 and 15.3±7.4, and 27.2±14 and 10.9±3 in groups 1-3, respectively (all P<0.01).ConclusionOur anatomical success rate was high. The key element in achieving this outcome was the establishment of a patent communication between the vitreous cavity and the anterior chamber.
Matsuo, Toshihiko; Takeda, Yoshimasa; Ohtsuka, Aiji
2013-01-01
The purpose of this study was to develop a series of stereoscopic anatomical images of the eye and orbit for use in the curricula of medical schools and residency programs in ophthalmology and other specialties. Layer-by-layer dissection of the eyelid, eyeball, and orbit of a cadaver was performed by an ophthalmologist. A stereoscopic camera system was used to capture a series of anatomical views that were scanned in a panoramic three-dimensional manner around the center of the lid fissure. The images could be rotated 360 degrees in the frontal plane and the angle of views could be tilted up to 90 degrees along the anteroposterior axis perpendicular to the frontal plane around the 360 degrees. The skin, orbicularis oculi muscle, and upper and lower tarsus were sequentially observed. The upper and lower eyelids were removed to expose the bulbar conjunctiva and to insert three 25-gauge trocars for vitrectomy at the location of the pars plana. The cornea was cut at the limbus, and the lens with mature cataract was dislocated. The sclera was cut to observe the trocars from inside the eyeball. The sclera was further cut to visualize the superior oblique muscle with the trochlea and the inferior oblique muscle. The eyeball was dissected completely to observe the optic nerve and the ophthalmic artery. The thin bones of the medial and inferior orbital wall were cracked with a forceps to expose the ethmoid and maxillary sinus, respectively. In conclusion, the serial dissection images visualized aspects of the local anatomy specific to various procedures, including the levator muscle and tarsus for blepharoptosis surgery, 25-gauge trocars as viewed from inside the eye globe for vitrectomy, the oblique muscles for strabismus surgery, and the thin medial and inferior orbital bony walls for orbital bone fractures.
Transiting Exoplanet Survey Satellite (TESS) Briefing
2018-03-28
A model of the Transiting Exoplanet Survey Satellite (TESS) and a spare camera lens are seen during a media briefing, Wednesday, March 28, 2018 at NASA Headquarters in Washington. Photo Credit: (NASA/Bill Ingalls)
Computational Model for Oxygen Transport and Consumption in Human Vitreous
Filas, Benjamen A.; Shui, Ying-Bo; Beebe, David C.
2013-01-01
Purpose. Previous studies that measured liquefaction and oxygen content in human vitreous suggested that exposure of the lens to excess oxygen causes nuclear cataracts. Here, we developed a computational model that reproduced available experimental oxygen distributions for intact and degraded human vitreous in physiologic and environmentally perturbed conditions. After validation, the model was used to estimate how age-related changes in vitreous physiology and structure alter oxygen levels at the lens. Methods. A finite-element model for oxygen transport and consumption in the human vitreous was created. Major inputs included ascorbate-mediated oxygen consumption in the vitreous, consumption at the posterior lens surface, and inflow from the retinal vasculature. Concentration-dependent relations were determined from experimental human data or estimated from animal studies, with the impact of all assumptions explored via parameter studies. Results. The model reproduced experimental data in humans, including oxygen partial pressure (Po2) gradients (≈15 mm Hg) across the anterior-posterior extent of the vitreous body, higher oxygen levels at the pars plana relative to the vitreous core, increases in Po2 near the lens after cataract surgery, and equilibration in the vitreous chamber following vitrectomy. Loss of the antioxidative capacity of ascorbate increases oxygen levels 3-fold at the lens surface. Homogeneous vitreous degeneration (liquefaction), but not partial posterior vitreous detachment, greatly increases oxygen exposure to the lens. Conclusions. Ascorbate content and the structure of the vitreous gel are critical determinants of lens oxygen exposure. Minimally invasive surgery and restoration of vitreous structure warrant further attention as strategies for preventing nuclear cataracts. PMID:24008409
Computational model for oxygen transport and consumption in human vitreous.
Filas, Benjamen A; Shui, Ying-Bo; Beebe, David C
2013-10-15
Previous studies that measured liquefaction and oxygen content in human vitreous suggested that exposure of the lens to excess oxygen causes nuclear cataracts. Here, we developed a computational model that reproduced available experimental oxygen distributions for intact and degraded human vitreous in physiologic and environmentally perturbed conditions. After validation, the model was used to estimate how age-related changes in vitreous physiology and structure alter oxygen levels at the lens. A finite-element model for oxygen transport and consumption in the human vitreous was created. Major inputs included ascorbate-mediated oxygen consumption in the vitreous, consumption at the posterior lens surface, and inflow from the retinal vasculature. Concentration-dependent relations were determined from experimental human data or estimated from animal studies, with the impact of all assumptions explored via parameter studies. The model reproduced experimental data in humans, including oxygen partial pressure (Po2) gradients (≈15 mm Hg) across the anterior-posterior extent of the vitreous body, higher oxygen levels at the pars plana relative to the vitreous core, increases in Po2 near the lens after cataract surgery, and equilibration in the vitreous chamber following vitrectomy. Loss of the antioxidative capacity of ascorbate increases oxygen levels 3-fold at the lens surface. Homogeneous vitreous degeneration (liquefaction), but not partial posterior vitreous detachment, greatly increases oxygen exposure to the lens. Ascorbate content and the structure of the vitreous gel are critical determinants of lens oxygen exposure. Minimally invasive surgery and restoration of vitreous structure warrant further attention as strategies for preventing nuclear cataracts.
Visual and anatomical outcome of macular hole surgery at a tertiary healthcare facility.
Kumari, Komalta; Tahir, Muhammad Ali; Cheema, Alyscia
2017-01-01
To assess visual and anatomical outcome of full thickness macular hole (FTMH) surgery with ILM peeling using brilliant blue G dye. Thirty patients who had clinically evident macular hole were selected. Pre-operative Optical Coherence Tomography (OCT) was done. In all cases vitrectomy was performed via 23guage 3 ports pars plana (3PPV) vitrectomy system and Brilliant blue G dye, 0.5ml dye was injected over macula which resulted in light blue stain of ILM and peeling was performed around hole in circular motion and after gas fluid exchange gas tamponade with SF6 was done. Final visual and anatomical outcome was measured as postoperative BCVA and postoperative OCT at three months respectively. Descriptive statistics were computed. Paired t-test was applied. P value≤0.05 were considered as significant. There were 12 male and 18 female patients. The mean age was 57.40±4.76 years. The mean size of macular hole was 452.20±242.33μm. The mean duration of symptoms was 16.73±13.49 weeks. Mean pre operative BCVA was 1.30±0.73 log MAR and post operative was 0.51±0.23 log MAR. Mean increased BCVA was found to be 0.22±0.13 log MAR. Primary closure of hole was achieved in 29(96.7%). Significant mean difference was found in pre operative and post operative BCVA. Brilliant blue G exhibits sufficient staining qualities and safety profile to peel ILM in the management of full thickness macular hole with significant visual and anatomical improvement.
Leisser, Christoph; Hackl, Christoph; Hirnschall, Nino; Luft, Nikolaus; Döller, Birgit; Draschl, Petra; Rigal, Karl; Findl, Oliver
2016-04-01
The aim of this study was to examine the quality of intraoperative visualization of the posterior hyaloid, epiretinal membrane (ERM), inner limiting membrane (ILM), and hyporeflective subfoveal zone with a commercially available, microscope-integrated spectral-domain OCT setup (mi-SD-OCT) (Rescan 700; Carl Zeiss Meditec AG, Germany). Twenty patients prospectively scheduled for pars plana vitrectomy with membrane peeling due to an idiopathic ERM were included. Standard 23-gauge, three-port pars plana vitrectomy with membrane peeling and staining of the ERM with a trypan blue-based chromovitrectomy dye was performed in all cases. Intraoperative SD-OCT was performed before and after peeling and visualization of the posterior hyaloid, ERM, ILM, and presence of subfoveal hyporeflective zones were examined. OCT follow-ups were performed 2 days and 3 months after surgery. The study was approved by the local ethics committee of the city of Vienna. Successful intraoperative visualization of ERM by mi-SD-OCT was possible in all cases. The posterior hyaloid and ILM could not be seen in the mi-SD-OCT scans, whereas an intraoperative subfoveal hyporeflective zone presented in 35% of cases. In 12.5% an independent subfoveal hyporeflective zone presented postoperatively. Visual acuity improved in 93.8% of patients after surgery. mi-SD-OCT appears to be a valuable tool for intraoperative visualization of the ERM and offers immediate visualization of retinal anatomy during peeling. Therefore, it adds to the understanding of intraoperative traumatic changes due to the peeling procedure. Copyright 2016, SLACK Incorporated.
Leisser, Christoph; Hirnschall, Nino; Hackl, Christoph; Döller, Birgit; Varsits, Ralph; Ullrich, Marlies; Kefer, Katharina; Karl, Rigal; Findl, Oliver
2018-02-20
Epiretinal membranes (ERM) are macular disorders leading to loss of vision and metamorphopsia. Vitrectomy with membrane peeling displays the gold standard of care. Aim of this study was to assess risk factors for postoperative intraretinal cystoid changes in a study population randomized for balanced salt solution and air-tamponade at the end of surgery. A prospective randomized study, including 69 eyes with idiopathic ERM. Standard 23-gauge three-port pars plana vitrectomy with membrane peeling, using intraoperative optical coherence tomography (OCT), was performed. Randomization for BSS and air-tamponade was performed prior to surgery. Best-corrected visual acuity improved from 32.9 letters to 45.1 letters 3 months after surgery. Presence of preoperative intraretinal cystoid changes was found to be the only risk factor for presence of postoperative intraretinal cystoid changes 3 months after surgery (p = 0.01; odds ratio: 8.0). Other possible risk factors such as combined phacoemulsification with 23G-ppv and membrane peeling (p = 0.16; odds ratio: 2.4), intraoperative subfoveal hyporeflective zones (p = 0.23; odds ratio: 2.6), age over 70 years (p = 0.29; odds ratio: 0.5) and air-tamponade (p = 0.59; odds ratio: 1.5) were not found to be significant. There is strong evidence that preoperative intraretinal cystoid changes lead to smaller benefit from surgery. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
2009-11-27
CAPE CANAVERAL, Fla. - At NASA's Kennedy Space Center in Florida, space shuttle Atlantis is towed from the Shuttle Landing Facility toward the 525-foot-tall Vehicle Assembly Building in the background. Atlantis touched down on Runway 33 after 11 days in space, completing the 4.5-million mile STS-129 mission to the International Space Station on orbit 171. Once Atlantis arrives in Orbiter Processing Facility-1, processing will begin for its next mission, designated STS-132. The 34th shuttle mission to the International Space Station, Atlantis will deliver an Integrated Cargo Carrier and Russian-built Mini Research Module, or MRM, to the orbiting laboratory on STS-132. The second in a series of new pressurized components for Russia, the MRM will be permanently attached to the bottom port of the Zarya module. The Russian module also will carry U.S. pressurized cargo. Three spacewalks are planned to stage spare components outside the station, including six spare batteries, a boom assembly for the Ku-band antenna and spares for the Canadian Dextre robotic arm extension. A radiator, airlock and European robotic arm for the Russian Multi-Purpose Laboratory Module also are payloads on the flight. Photo credit: NASA/Jack Pfaller
Macular retinoschisis in eyes with glaucomatous optic neuropathy: Vitrectomy and natural course.
Yoshikawa, Tadanobu; Yamanaka, Chihiro; Kinoshita, Takamasa; Morikawa, Shohei; Ogata, Nahoko
2018-02-01
Our purpose was to determine the effectiveness of vitrectomy in resolving the macular retinoschisis in an eye with glaucomatous optic neuropathy and also to determine the natural course of macular retinoschisis. This was a retrospective case series of patients who were diagnosed with macular retinoschisis and glaucomatous optic neuropathy. Fourteen eyes of 13 patients were studied. Patients with high myopia, vitreomacular traction syndrome, and the pit macular syndrome were excluded. There were three men and ten women, and 12 had unilateral and one had bilateral macular retinoschisis. Vitrectomy was performed for a serous retinal detachment, macular hole, or severe visual loss in five eyes. The mean follow-up time was 68.8 months in these five eyes, and the macular retinoschisis was resolved and the best-corrected visual acuity (BCVA) at the final visit was significantly improved in all eyes (P = 0.007). However, two of these fiv e eyes developed a macular hole and required a second vitrectomy. Of the nine eyes without treatment with a mean follow-up time of 29.0 months, the BCVA at the final visit remained unchanged from the baseline BCVA in all eyes. The macular retinoschisis was resolved or reduced in three eyes without treatment. Vitrectomy was effective for the resolution of macular retinoschisis in eyes with glaucomatous optic neuropathy and serous retinal detachment or macular hole or severe reduction of the BCVA. Macular retinoschisis can be resolved without a reduction of the BCVA in some cases without treatment.
Mason, John O; Neimkin, Michael G; Mason, John O; Friedman, Duncan A; Feist, Richard M; Thomley, Martin L; Albert, Michael A
2014-06-01
To determine the safety, efficacy, and quality of life improvement following sutureless 25-gauge pars plana vitrectomy for symptomatic floaters. Patients with symptomatic vitreous floaters who underwent sutureless vitrectomy between January 2008 and January 2011 were included. Data were collected regarding baseline preoperative characteristics, postoperative outcomes, complications, and a nine-item quality-of-life survey completed by each patient. One hundred and sixty-eight eyes (143 patients) underwent sutureless 25-gauge pars plana vitrectomy for symptomatic vitreous floaters. Mean Snellen visual acuity was 20/40 preoperatively and improved to 20/25 postoperatively (P < 0.0001). Iatrogenic retinal breaks occurred in 12 of 168 eyes (7.1%). Intraoperative posterior vitreous detachment induction was not found to increase the risk of retinal breaks (P = 1.000). Postoperative complications occurred in three eyes, of which one had transient cystoid macular edema and two had transient vitreous hemorrhage. Approximately 88.8% of patients completed a quality-of-life survey, which revealed that 96% were "satisfied" with the results of the operation, and 94% rated the experience as a "complete success." Sutureless 25-gauge pars plana vitrectomy for symptomatic vitreous floaters improved visual acuity, resulted in a high patient satisfaction quality-of-life survey, and had a low rate of postoperative complications. Sutureless pars plana vitrectomy should be considered as a viable means of managing patients with symptomatic vitreous floaters.
Abulon, Dina Joy K; Buboltz, David C
2015-02-01
To measure flow rate of balanced salt solution and IOP during simulated vitrectomy using two sets of high-speed dual-pneumatic probes. A closed-model eye system measured IOP and flow rate of a balanced salt solution through infusion cannula. The Constellation Vision System was tested with two sets of high-speed dual-pneumatic probes (UltraVit 23-gauge and enhanced 25+-gauge 5000-cpm probes; UltraVit 23-gauge and enhanced 25+-gauge 7500-cpm probes; n = 6 each) under different vacuum levels and cut rates in three duty cycle modes. In both probe sets, flow rates were dependent on cut rate with the biased open and biased closed duty cycles. Flow rates were highest with the biased open duty cycle, lower with the 50/50 duty cycle, and lowest with the biased closed duty cycle. IOP, as expected, was inversely associated with flow rate using both probe sets. The 7500-cpm probes offer greater control and customization compared with 5000-cpm probes under certain experimental conditions. At maximum cut rates, performance of 7500-cpm probes was similar to that of 5000-cpm probes, suggesting that 7500-cpm probes may be used without sacrifice of flow rate and IOP stability. Customization of vitrectomy parameters allows greater surgeon control during vitrectomy and may expand the usefulness of vitrectomy probes.
A RESCUE THERAPY FOR PERSISTENT OPTIC DISK PIT MACULOPATHY IN PREVIOUSLY VITRECTOMIZED EYES.
Figueroa, Marta S; Nadal, Jeroni; Contreras, Inés
2018-01-01
To report the results of vitrectomy with platelet-rich plasma (PRP) application and gas tamponade as a rescue therapy in previously vitrectomized eyes with optic disk pit (ODP) maculopathy. Three patients with visual loss due to persistent or recurrent ODP maculopathy who had undergone previous vitrectomy were offered application of PRP. Platelet-rich plasma was obtained by centrifugation of a blood sample from each patient. Surgery consisted of vitrectomy and internal limiting membrane peeling if the membrane had not been already removed (in two eyes). After fluid/air exchange, three drops of PRP were applied on the ODP followed by 8% C3F8 tamponade. Immediately after surgery, the patient remained supine for 30 minutes and then kept a face-down position for 2 weeks. Optic disk pit maculopathy improved as soon as two weeks after surgery and resolved in all eyes between six and eight months after PRP application. Patients were followed up for three years, with no recurrences. Visual acuity remained stable in one eye and improved in two eyes. Vitrectomy with PRP application may be useful as a rescue therapy in patients with refractory ODP maculopathy. Platelet-rich plasma may act by promoting the closure of the communication between the vitreous and the intraretinal/subretinal space at the pit. This treatment may avoid potentially harmful maneuvers that have been used to treat ODP maculopathy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dormer, J; Kassaee, A; Lin, H
2014-06-01
Purpose: To evaluate use of intensity modulated proton therapy (IMPT) and number of beams for sparing cochlea in treatment of whole brain for pediatric medulloblastoma patients. Methods: In our institution, craniospinal irradiation patients are treated in supine position on our proton gantries using pencil beam scanning with each beam uniformly covering the target volume (SFUD). Each treatment plan consists of two opposed lateral whole brain fields and one or two spinal fields. For sparing the cochlea for the whole brain treatment, we created three different plans using IMPT for five pediatric patients. The first plan consisted of two lateral fields,more » the second two lateral fields and a superior-inferior field, and the third two lateral fields and two superior oblique fields. Optimization was performed with heavy weights applied to the eye, lens and cochlea while maintaining a dose prescription of 36 Gy to the whole brain. Results: IMPT plans reduce the dose to the cochlea. Increasing the number of treatment fields was found to lower the average dose to the cochlea: 15.0, 14.5 and 12.5 Gy for the two-field, three-field, and four-field plans respectively. The D95 for the two-field plan was 98.2%, compared to 100.0% for both the three-field and four-field plan. Coverage in the mid-brain was noticeably better in the three- and four-field plans, with more dose conformality surrounding the cochlea. Conclusion: IMPT plans for CSI and the whole brain irradiations are capable of sparing cochlea and reduce the dose considerably without compromising treating brain tissues. The reduction in average dose increases with three and four field plans as compared to traditional two lateral beam plans.« less
Angular and linear fields of view of Galilean telescopes and telemicroscopes.
Katz, Milton
2007-06-01
The calculation of the angular fields of view (FOVs) of Galilean telescopes generally necessitates the calculation of the pupils and ports. This, in turn, requires knowledge of the optical design of the telescope, in particular, the focal lengths or powers of the objective and ocular lenses. Equations for finding the FOV that obviate the need to calculate pupils and ports, or even to know the lens powers of the telescope, are presented in this article. The equations can be used to find the FOVs in image space of real Galilean telescopes of known magnification, merely by measuring the distance between the objective and ocular lenses and the diameter of the objective lens. The equations include the effects of eye pupil diameter and eye relief. Linear FOVs (LFOVs) of Galilean telemicroscopes are similarly determined. Two image space angular FOV equations were derived: (1) an equation to determine the angular FOVs of a telescope with various amounts of vignetting and eye relief; and (2) an equivalent equation for the LFOVs of telescopes fitted with lens caps for near vision. The FOV increases linearly with increasing vignetting. Increasing the eye relief results in a nonlinear decrease in the FOV, shown as a fraction of the normalized value for zero eye relief. Decrements in the FOVs with increasing eye relief as a fraction of the normalized field angle when the eye relief = 0 are shown to be constant regardless of the vignetting level. A transition of the objective lens from field stop to aperture stop occurs when the eye pupil diameter exceeds the diameter of the objective lens divided by the magnification. Equations have been derived for Galilean telescopes and telemicroscopes that make it unnecessary to find pupils and ports, or to know the powers of the lenses. They provide a direct and simple evaluation of angular and LFOVs as functions of magnification, objective lens diameter, eye pupil diameter, eye relief, and vignetting, and enable comparisons of actual telescopes.
Lyu, J; Zhao, P-q
2016-01-01
Purpose We report a simplified ab externo scleral fixation technique to manage the late dislocation of scleral-sutured polymethyl methacrylate (PMMA) intraocular lenses (IOLs) in the absence of capsule support. Materials and methods The technique was performed on five eyes of five patients. Symmetrical scleral pocket tunnels without conjunctival peritomy were created. An anterior vitrectomy via a limbal approach with an anterior chamber infusion or a 3-port pars plana vitrectomy was performed to rescue the dislocated IOL. A long straight suture needle and 23-gauge vitreoretinal forceps were used to conveniently reposition the IOL and loop sutures through the IOL positioning eyelets without externalizing IOL haptics. The outside suture knots were buried under the roof of the scleral tunnels. Results The patients were followed for 5–14 months after surgery. All the operated eyes quickly recovered with negligible corneal endothelial cell loss and mild inflammation. Visual acuity improvement and IOL centration were achieved in all eyes with no major complications. Conclusion The simplified ab externo scleral fixation technique offers an effective and minimally invasive surgical alternative to salvage dislocated previously scleral-sutured PMMA IOLs. PMID:26795420
Lyu, J; Zhao, P-Q
2016-05-01
PurposeWe report a simplified ab externo scleral fixation technique to manage the late dislocation of scleral-sutured polymethyl methacrylate (PMMA) intraocular lenses (IOLs) in the absence of capsule support.Materials and methodsThe technique was performed on five eyes of five patients. Symmetrical scleral pocket tunnels without conjunctival peritomy were created. An anterior vitrectomy via a limbal approach with an anterior chamber infusion or a 3-port pars plana vitrectomy was performed to rescue the dislocated IOL. A long straight suture needle and 23-gauge vitreoretinal forceps were used to conveniently reposition the IOL and loop sutures through the IOL positioning eyelets without externalizing IOL haptics. The outside suture knots were buried under the roof of the scleral tunnels.ResultsThe patients were followed for 5-14 months after surgery. All the operated eyes quickly recovered with negligible corneal endothelial cell loss and mild inflammation. Visual acuity improvement and IOL centration were achieved in all eyes with no major complications.ConclusionThe simplified ab externo scleral fixation technique offers an effective and minimally invasive surgical alternative to salvage dislocated previously scleral-sutured PMMA IOLs.
Combustion pinhole-camera system
Witte, A.B.
1982-05-19
A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.
Combustion pinhole camera system
Witte, A.B.
1984-02-21
A pinhole camera system is described utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor. 2 figs.
Combustion pinhole camera system
Witte, Arvel B.
1984-02-21
A pinhole camera system utilizing a sealed optical-purge assembly which provides optical access into a coal combustor or other energy conversion reactors. The camera system basically consists of a focused-purge pinhole optical port assembly, a conventional TV vidicon receiver, an external, variable density light filter which is coupled electronically to the vidicon automatic gain control (agc). The key component of this system is the focused-purge pinhole optical port assembly which utilizes a purging inert gas to keep debris from entering the port and a lens arrangement which transfers the pinhole to the outside of the port assembly. One additional feature of the port assembly is that it is not flush with the interior of the combustor.
[Complications of a voluminous congenital ciliary body cyst].
Kottler, Ulrike B; Schwenn, Oliver
2002-09-01
Multiple cysts of iris and ciliary body may cause many complications such as acute or chronic angle closure glaucoma. We present a boy with multiple congenital cysts of the iris pigment epithelium and a voluminous cyst of the unpigmented ciliary body epithelium of the right eye. This resulted in lenticular astigmatism, concomitant strabismus divergens and subsequently to anisometropia. The voluminous cyst (8 x 12 mm in diameter) was folded around the lens, reached the optic axis and resulted in displacement of the lens and contact between the iris and the corneal endothelium from 6.30 to 11. After puncture and partial resection of the cyst at the age of 8 months the boy developed a subcapsular multivesicular cataractic clouding of the temporal lens and a progredient myopia (up to - 14.0/- 2.0/0 degrees ); in contrast the left eye was hyperopic (+ 3.5/- 3.75/0 degrees ). The lens was subluxated superonasally due to congenital damage of the zonular fibres. Because development of visual acuity seemed limited by these determinants (20/200 at the right eye), cataract surgery with posterior capsulorhexis, anterior vitrectomy, and implantation of a capsular tension ring and posterior chamber intraocular lens was performed at the age of nearly five. Actually, there is an orthotropia, best corrected visual acuity in the distance of 20/32 in the right and 20/20 in the left eye; binocular vision is somewhat restricted. Usually congenital cysts are clinically not very relevant; occasionally surgical intervention is required to ensure adequate development of visual acuity.
ReSure Sealant for Pars Plana Vitrectomy Wound Closure.
Ho, Vincent Y; Shah, Gaurav K; Liu, Enchun M
2015-01-01
ReSure Sealant (Ocular Therapeutix, Bedford, MA) is an ocular sealant that demonstrated both safety and effectiveness in a prospective, randomized clinical trial for sealing clear corneal incisions following cataract surgery and intraocular lens placement in adults.1 PATIENTS AND METHODS: This is the first literature report of ReSure Sealant used for the closure of 23-gauge (G) pars plana vitrectomy (PPV) sclerotomies. A 70-year-old pseudophakic female with a history of epiretinal membrane and branch retinal vein occlusion of the right eye underwent 23-G PPV, membrane peel, and air-fluid exchange and was found to have leaking subconjunctival air at the end of the case. A linear conjunctival incision was performed to access the sclerotomy site. The incisions were then carefully dried before the sealant was applied to seal both the sclera and conjunctiva. After polymerization, the sealant formed a polyethylene glycol (PEG) hydrogel that was 89% water and 9.44% PEG. PEG is a synthetic material that is non-toxic and inert and, thus, suitable for use in medical products. ReSure Sealant may be a safe, quick method to close sclerotomy wounds in select cases. [ Copyright 2015, SLACK Incorporated.
Clinical and biometric determinants of actual lens position after cataract surgery.
Plat, Julien; Hoa, Didier; Mura, Frederic; Busetto, Timothe; Schneider, Christelle; Payerols, Arnaud; Villain, Max; Daien, Vincent
2017-02-01
To evaluate the preoperative clinical and biometric determinants associated with the actual lens position after cataract surgery. Department of Ophthalmology, University Hospital of Montpellier, France. Prospective longitudinal cohort study. The data collected included clinical factors (age, sex, history of vitrectomy) and biometry factors (axial length [AL], anterior chamber depth [ACD], lens thickness, white-to-white [WTW] distance) that might affect actual lens position. Each patient had optical low-coherence reflectometry biometry (Lenstar) preoperatively and 1 month postoperatively. The actual lens position was measured as the postoperative position of the center of the intraocular lens (IOL). Patients were stratified into 3 groups by type of IOL: Acrysof SN60WF or SN6AT (Group 1), Tecnis ZCB00 or ZCT (Group 2), and Asphina 409 MV (Group 3). The study comprised 168 eyes (mean age 73.3 years ± 9.8 [SD]). The mean actual lens position was 4.88 ± 0.29 mm, 5.01 ± 0.29 mm, and 5.05 ± 0.32 mm in Group 1 (n = 67 eyes), Group 2 (n = 52 eyes), and Group 3 (n = 49 eyes), respectively. In the overall population, AL, ACD, anterior segment depth, and WTW distance were correlated with actual lens position (r = 0.48, P < .0001; r = 0.64, P < .001; r = 0.58, P < .0001; r = 0.39, P < .001, respectively). The AL, ACD, anterior segment depth, and WTW distance correlated with actual lens position after cataract surgery. The integration of these data in IOL formulas could help improve refractive outcomes after the surgery. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
[Pay attention to the complexity of cataract surgery of no vitreous eyes].
Bao, Y Z
2017-04-11
With wide-spread performance of pars plana vitrectomy, cataract surgeries with no vitreous are getting more and more. This kind of surgery has great difference between individuals and it lacks randomized large sample clinical trial. Surgical strategy decision was basically relied on the surgeon's personal experience. We should fully aware the individual and common characteristics of no vitreous cataract surgery. Surgical time should be carefully decided. Complete ocular examination, evaluation, design of cataract surgical procedure and appropriate intra-ocular lens selection are needed. We must pay highly attention on the cataract surgery of no vitreous eyes. (Chin J Ophthalmol, 2017, 53: 241-243) .
Effect of topical rebamipide on conjunctival goblet cell recovery after vitrectomy
Kato, Kumiko; Takashima, Yuko; Matsunaga, Koichi; Sugimoto, Masahiko; Matsubara, Hisashi; Hirano, Koji; Kondo, Mineo
2016-01-01
In vitro and in vivo experiments have shown that topical rebamipide will increase the number of goblet cells in the bulbar conjunctiva. The purpose of this study was to determine whether topical rebamipide will enhance the recovery of conjunctival goblet cells that were damaged during vitrectomy. Forty patients who underwent vitrectomy surgery were studied. The 40 patients consisted of 20 with diabetes mellitus (DM) and 20 patients without DM. They were randomized in a 1:1 ratio into groups that were treated or not treated with topical 2% rebamipide after the surgery. Impression cytology was performed at the end of surgery and at 14 days after the surgery. The mean goblet cell density of each specimen was determined by averaging the total number of goblet cells obtained from three consecutive high magnification microscopic images. In patients without DM, the mean goblet cell density at 14 days after the vitrectomy was significantly higher in eyes with topical rebemipide than in eyes without rebemipide (P < 0.01). In patients with DM, a similar tendency was observed but the difference was not significant (P = 0.09). These results suggest that topical rebamipide can be helpful in patients with globlet cell damage that occur during and after vitrectomy. PMID:26762482
Effect of topical rebamipide on conjunctival goblet cell recovery after vitrectomy.
Kato, Kumiko; Takashima, Yuko; Matsunaga, Koichi; Sugimoto, Masahiko; Matsubara, Hisashi; Hirano, Koji; Kondo, Mineo
2016-01-14
In vitro and in vivo experiments have shown that topical rebamipide will increase the number of goblet cells in the bulbar conjunctiva. The purpose of this study was to determine whether topical rebamipide will enhance the recovery of conjunctival goblet cells that were damaged during vitrectomy. Forty patients who underwent vitrectomy surgery were studied. The 40 patients consisted of 20 with diabetes mellitus (DM) and 20 patients without DM. They were randomized in a 1:1 ratio into groups that were treated or not treated with topical 2% rebamipide after the surgery. Impression cytology was performed at the end of surgery and at 14 days after the surgery. The mean goblet cell density of each specimen was determined by averaging the total number of goblet cells obtained from three consecutive high magnification microscopic images. In patients without DM, the mean goblet cell density at 14 days after the vitrectomy was significantly higher in eyes with topical rebemipide than in eyes without rebemipide (P < 0.01). In patients with DM, a similar tendency was observed but the difference was not significant (P = 0.09). These results suggest that topical rebamipide can be helpful in patients with globlet cell damage that occur during and after vitrectomy.
Paskowitz, D M; Nguyen, Q D; Gehlbach, P; Handa, J T; Solomon, S; Stark, W; Shaikh, O; Semba, C; Gadek, T R; Do, D V
2012-07-01
A growing body of evidence points to a role for inflammation mediated by lymphocyte function-associated antigen-1 (LFA-1) and its ligand intercellular adhesion molecule-1 in the pathogenesis of diabetic macular oedema. This phase 1b clinical trial assessed the safety, tolerability, and pharmacokinetics of topically administered SAR 1118, a novel LFA-1 antagonist, in human subjects. In this prospective, randomized, double-masked trial, 13 subjects scheduled for vitrectomy received one of three concentrations of topical SAR 1118 (0.1, 1.0, or 5.0%) twice daily for 1 week before surgery. Undiluted aqueous and vitreous samples were collected at surgery and analysed for the concentration of the medication. All subjects completed the entire course of medication. The only adverse events reported were instillation site irritation (4/13, 31%) and dysgeusia (3/13, 23%). These were mild and transient, occurring at the highest dose. Mean concentrations (ng/ml) of SAR 1118 in the aqueous humour were 0.25, 37.2, and 101.1 for the 0.1%, 1.0%, and 5.0% dose groups, respectively. SAR 1118 was below the level of detection (0.5 ng/ml) for all vitreous samples except in a single subject who had a history of prior vitrectomy and a dislocated intraocular lens. Topical SAR 1118 was safe and well tolerated, and dose-dependent levels of drug were detected in aqueous. However, vitreous levels were below the threshold of detection with the concentrations tested. Further investigation of this medication for posterior segment applications would require intravitreal delivery or chemical modification of the drug.
Design of an open-ended plenoptic camera for three-dimensional imaging of dusty plasmas
NASA Astrophysics Data System (ADS)
Sanpei, Akio; Tokunaga, Kazuya; Hayashi, Yasuaki
2017-08-01
Herein, the design of a plenoptic imaging system for three-dimensional reconstructions of dusty plasmas using an integral photography technique has been reported. This open-ended system is constructed with a multi-convex lens array and a typical reflex CMOS camera. We validated the design of the reconstruction system using known target particles. Additionally, the system has been applied to observations of fine particles floating in a horizontal, parallel-plate radio-frequency plasma. Furthermore, the system works well in the range of our dusty plasma experiment. We can identify the three-dimensional positions of dust particles from a single-exposure image obtained from one viewing port.
Transiting Exoplanet Survey Satellite (TESS) Briefing
2018-03-28
Jeff Volosin, TESS project manager, NASA’s Goddard Space Flight Center, holds a spare camera lens and a model of the Transiting Exoplanet Survey Satellite (TESS) during a media briefing, Wednesday, March 28, 2018 at NASA Headquarters in Washington. Photo Credit: (NASA/Bill Ingalls)
Velez-Montoya, Raul; Guerrero-Naranjo, Jose Luis; Garcia-Aguirre, Gerardo; Morales-Cantón, Virgilio; Fromow-Guerra, Jans; Quiroz-Mercado, Hugo
2011-01-01
Background Perfluorocarbon liquid (PCL)-perfused vitrectomy has been shown in previous studies to be feasible, safe, and to have advantages in managing complicated cases of tractional retinal detachment. The present study had the objectives of describing the anatomical results and measuring surgical time and PCL consumption when combining PCL-perfused techniques with modern vitrectomy equipment. Methods A prospective, interventional consecutive case series was investigated. We enrolled patients with diabetic tractional retinal detachment, complicated by proliferative vitreoretinopathy and poor vision. A 23 gauge PCL-perfused vitrectomy was done with three-dimensional settings. During the procedure, we assessed the degree of surgical bleeding, visualization quality, and difficulty of membrane dissections. Visual acuity, intraocular pressure, and anatomical success were assessed at one and 3 months of follow-up. Results Twelve patients were enrolled in this study. There were no statistical significant changes in intraocular pressure and visual acuity throughout the follow-up period. Surgery was performed in a hemorrhage-free environment in almost all cases, with good visualization and low technical difficulty. The mean complete surgical time was 94.92 ± 25.03 minutes. The mean effective vitrectomy time was 22.50 ± 19.04 minutes and the mean PCL consumption was 25.08 ± 9.76 mL, with a speed of 1.11 mL/minute. Anatomical success was 67% at 3 months. Conclusion Although the technique proved to have some advantages in managing complicated cases of diabetic tractional retinal detachment, there was a high consumption of PCL. A redesign of the entire system is needed in order to decrease the amount of PCL needed for the technique. PMID:22267907
McClellan, Scott F; Soiberman, Uri; Gehlbach, Peter L; Murakami, Peter N; Stark, Walter J
2015-08-01
We have developed a novel surgical technique, to our knowledge, for the management of subluxated crystalline lenses involving preplacement of an iris-sutured posterior chamber intraocular lens (PCIOL) before pars plana vitrectomy and lensectomy. To investigate the outcomes of eyes with subluxated crystalline lenses, predominantly a result of Marfan syndrome (14 eyes [58%]) or trauma (5 eyes [21%]), that underwent pars plana vitrectomy and lensectomy with placement of an iris-sutured PCIOL. We performed a retrospective, noncomparative case series of 24 eyes from 17 consecutive adult patients with surgically treated subluxated crystalline lenses presenting to the Wilmer Eye Institute at Johns Hopkins Hospital from October 6, 2006, through May 1, 2013. The mean (SD) postoperative follow-up was 24.4 (20.5) months for eyes with at least 6 months of follow-up (last date, October 13, 2014). We performed the analysis from January 21, 2014, through January 3, 2015. Improvement in best-corrected visual acuity using an automated Snellen chart and induction of astigmatism for eyes with at least 6 months of follow-up (n = 18) and IOL stability during follow-up for all eyes (n = 24). The mean (SD) age at surgery was 49.4 (10.7 [range, 29-67]) years. We found an improvement in mean (SD [95% CI]) best-corrected visual acuity from 0.66 (0.71 [0.30-1.02]) logMAR preoperatively (Snellen equivalent, approximately 20/90; range, 20/30 to hand motions) to 0.07 (0.11 [95% CI, 0.01-0.12]) logMAR postoperatively (Snellen equivalent, approximately 20/23; range, 20/15 to 20/50). We found little change in astigmatism postoperatively (mean change, -0.1 [95% CI, -0.5 to 0.13] diopters). Postoperative complications included retinal detachment (1 eye [4%]), retained cortical fragment (1 [4%]), cystoid macular edema (2 [8%]), and IOL subluxation (3 [13%]) owing to haptic slippage within 3 months of the procedure. The overall probability of successfully achieving placement of a centered iris-sutured PCIOL in patients with follow-up of longer than 6 months (n = 18) was 100% (95% CI, 81.5%-100%). Placement of iris-sutured PCIOLs at the time of subluxated lens extraction with a pars plana surgical approach yields favorable results in terms of postoperative visual outcomes and surgical complications. This technique offers an effective procedure for surgeons to use when treating clinically significant subluxated crystalline lenses.
Vitrectomy for vitreous floaters: analysis of the benefits and risks.
Sommerville, Drew N
2015-05-01
To review the pros and cons of small-gauge vitrectomy for symptomatic floaters. Current treatment options for floaters include Nd:YAG vitreolysis and pars plana vitrectomy. There are risks and benefits associated with vitrectomy for floaters. However, small-gauge vitrectomy is a minimally invasive way of removing the floaters. The current literature demonstrates vitrectomy has some risk, but is highly effective at improving vision, symptoms, contrast sensitivity, and quality of life. Small-gauge vitrectomy for floaters is a well tolerated and effective procedure to remove the symptomatic floaters. Symptomatic patients are willing to take some risk to have their troublesome vitreous floaters removed, often resulting in an improvement in their vision and quality of life.
Self-referencing remote optical probe
O'Rourke, Patrick E.; Prather, William S.; Livingston, Ronald R.
1991-01-01
A probe for remote spectrometric measurements of fluid samples having a hollow probe body with a sliding reflective plug therein and a lens at one end, ports for admitting and expelling the fluid sample and a means for moving the reflector so that reference measurement can be made with the reflector in a first position near the lens and a sample measurement can be made with the reflector away from the lens and the fluid sample between the reflector and the lens. Comparison of the two measurements will yield the composition of the fluid sample. The probe is preferably used for remote measurements and light is carried to and from the probe via fiber optic cables.
Self-referencing remote optical probe
O'Rourke, P.E.; Prather, W.S.; Livingston, R.R.
1991-08-13
A probe is described for remote spectrometric measurements of fluid samples having a hollow probe body with a sliding reflective plug therein and a lens at one end, ports for admitting and expelling the fluid sample and a means for moving the reflector so that reference measurement can be made with the reflector in a first position near the lens and a sample measurement can be made with the reflector away from the lens and the fluid sample between the reflector and the lens. Comparison of the two measurements will yield the composition of the fluid sample. The probe is preferably used for remote measurements and light is carried to and from the probe via fiber optic cables. 3 figures.
Nd:YAG vitreolysis and pars plana vitrectomy: surgical treatment for vitreous floaters.
Delaney, Y M; Oyinloye, A; Benjamin, L
2002-01-01
To determine the efficacy of Nd:YAG vitreolysis and pars plana vitrectomy in the treatment of vitreous floaters. This is a single centre retrospective study of 31 patients (42 eyes) who underwent 54 procedures, Nd:YAG vitreolysis or pars plana vitrectomy, for the treatment of vitreous floaters between January 1992 and December 2000. Main outcome measures were percentage symptomatic improvement following treatment and incidence of post-operative complications. Statistical analysis was performed using the Fisher exact test. Posterior vitreous detachment was the primary cause of floaters in all 42 eyes with co-existing vitreous veils in three eyes and asteroid hyalosis in two eyes. Thirty-nine of 42 eyes received Nd:YAG vitreolysis. Thirty-eight percent found Nd:YAG vitreolysis moderately improved their symptoms while 61.5% found no improvement. After an average of 14.7 months follow-up no post-operative complications were recorded. Fifteen eyes underwent a pars plana vitrectomy, one with combined phacoemulsification and posterior chamber implantation and 11 following unsuccessful laser vitreolysis. Pars plana vitrectomy resulted in full resolution of symptoms in 93.3% of eyes. One patient developed a post-operative retinal detachment which was successfully treated leaving the patient with 6/5 VA. Patients' symptoms from vitreous floaters are often underestimated resulting in no intervention. This paper shows Nd:YAG vitreolysis to be a safe but only moderately effective primary treatment conferring clinical benefit in one third of patients. Pars plana vitrectomy, while offering superior results, should be reserved for patients who remain markedly symptomatic following vitreolysis, until future studies further clarify its role in the treatment of patients with floaters and posterior vitreous detachment.
Figueroa, Marta S; Contreras, Inés; Noval, Susana
2013-01-01
To evaluate the anatomic success rate, visual acuity (VA) changes, and complications of 23-G vitrectomy without associated scleral procedures for the treatment of primary rhegmatogenous retinal detachment (PRRD). Patients diagnosed with PRRD were considered for inclusion. Patients with evidence of proliferative vitreoretinopathy or coexisting ocular pathologies were excluded. Surgery consisted of 23-G vitrectomy with endolaser photocoagulation of retinal breaks and fluid-air-gas (12% C3F8) exchange. Minimum follow-up was 3 months. A total of 133 eyes of 118 patients were included. Fifty eyes were phakic and 83 pseudophakic. Mean time from diagnosis to surgery was 6.9 days (range 1-40). Mean VA improved significantly from 20/50 (range: hand movements to 20/20) to 20/30 (range: counting fingers to 20/16), with no statistically significant differences between phakic and pseudophakic eyes (p = 0.233). Visual acuity improved to 20/40 or better in 104 eyes (78.2%). A redetachment developed in 5 eyes (3.8%), so the primary anatomic success rate was 96.2%. Four eyes required a second surgical procedure and one eye a third to achieve retinal reattachment. Cataract progression in phakic eyes made cataract surgery necessary within 1 year of vitrectomy in 12/50 (24%) eyes. Subretinal perfluoro-N-octane (PFO) was detected in 6 eyes (4.5%). Twenty-three--gauge vitrectomy without scleral buckling seems to be an effective technique for the treatment of PRRD without proliferative vitreoretinopathy. The high anatomic success rate was comparable to that previously described with 20 G and scleral buckling. Complications were similar to those described for 20-G vitrectomy, except for retained subretinal PFO, which has a higher rate.
Auriol, Sylvain; Mahieu, Laurence; Brousset, Pierre; Malecaze, François; Mathis, Véronique
2013-01-01
To evaluate safety of medium-chain triglycerides used as a possible intraocular tamponading agent. A 20-gauge pars plana vitrectomy was performed in the right eye of 28 rabbits. An ophthalmologic examination was performed every week until rabbits were killed. At days 7, 30, 60, and 90, rabbits were killed and the treated eyes were examined macroscopically and prepared for histologic examination. Principal outcome was retinal toxicity evaluated by light and electron microscopy, and secondary outcomes were the presence of medium-chain triglyceride emulsification, inflammatory reactions, and the development of cataract. Histologic examination did not reveal any retinal toxicity. Two cases of moderate emulsification were observed, but in these cases, emulsification was caused by the perioperative injection of the agent and did not increase during the postoperative period. We noted 13 cases of inflammatory reaction in vitreous cavity and no case of inflammatory reaction in anterior chamber. Two eyes developed cataract as a result of perioperative trauma to the lens with the vitreous cutter and not secondary to the presence of medium-chain triglycerides in the vitreous cavity. Medium-chain triglycerides did not induce morphologic evidence of retinal toxicity. The results suggest that medium-chain triglycerides could be a promising alternative intraocular tamponading agent for the treatment of retinal detachments.
Beshears, David L.; Sitter, Jr., David N.; Andrews, William H.; Simpson, Marc L.; Abston, Ruth A.; Cates, Michael R.; Allison, Steve W.
2000-01-01
An apparatus for measuring the temperature of a moving substrate includes an air gun with a powder inlet port in communication with the outlet port of a powder reservoir, an air inlet port in communication with a pressurized air source, and an outlet nozzle spaced from and directed toward the moving substrate. The air gun is activated by the air pulses to spray controlled amounts of the powdered phosphor onto the moving substrate, where the phosphor assumes the temperature of the moving substrate. A laser produces light pulses, and optics direct the light pulses onto the phosphor on the moving substrate, in response to which the phosphor emits a luminescence with a decay rate indicative of the temperature of the phosphor. A collection lens is disposed to focus the luminescence, and a photodetector detects the luminescence focused by the collection lens and produces an electrical signal that is characteristic of the brightness of the luminescence. A processor analyzes the electrical signal to determine the decay characteristic of the luminescence and to determine the temperature of the phosphor from the decay characteristic.
Motoda, Saori; Shiraki, Nobuhiko; Ishihara, Takuma; Sakaguchi, Hirokazu; Kabata, Daijiro; Takahara, Mitsuyoshi; Kimura, Takekazu; Kozawa, Junji; Imagawa, Akihisa; Nishida, Kohji; Shintani, Ayumi; Iwahashi, Hiromi; Shimomura, Iichiro
2017-12-19
To clarify the association between perioperative variables and postoperative bleeding in pars plana vitrectomy for vitreous hemorrhage in diabetic retinopathy. The present retrospective study enrolled 72 eyes of 64 patients who were admitted to Osaka University Hospital between April 2010 and March 2014, and underwent vitrectomy for vitreous hemorrhage as a result of diabetic retinopathy. Postoperative bleeding developed in 12 eyes. Using binomial logistic regression analysis, we found that the duration of operation was the only significant variable associated with postoperative bleeding within 12 weeks after vitrectomy. Furthermore, Poisson regression analysis identified fasting blood glucose just before vitrectomy, no treatment with antiplatelet drugs and treatment with antihypertensive drugs, as well as duration of operation, to be significantly associated with the frequency of bleeding within 52 weeks after vitrectomy. Long duration of operation can be used to predict bleeding within both 12 and 52 weeks after vitrectomy. In addition, fasting blood glucose just before vitrectomy, no treatment with antiplatelet drugs and treatment with antihypertensive drugs might be risk factors for postoperative bleeding up to 1 year after vitrectomy. © 2017 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.
Kaidonis, Georgia; Hassall, Mark M; Phillips, Russell; Raymond, Grant; Saha, Niladri; Wong, George Hc; Gilhotra, Jagjit S; Liu, Ebony; Burdon, Kathryn P; Henderson, Tim; Newland, Henry; Lake, Stewart R; Craig, Jamie E
2018-05-01
Visual outcomes following diabetic vitrectomy have not previously been studied in an Australian population. This analysis aimed to determine the rate of, and factors associated with visual success following diabetic vitrectomy performed for Indigenous and non-Indigenous Australians, and investigate factors predisposing to early progression to diabetic retinopathy (DR) requiring vitrectomy. Retrospective, population-based audit. All patients undergoing vitrectomy for the complications of DR in South Australia (SA) and the Northern Territory (NT) between 2007 and 2011. Medical records were audited and data collected, including demographics, diabetic history, past treatment for DR, indication for vitrectomy and visual acuity pre and postoperatively. Visual success (gain of ≥15 ETDRS letters) at 6 and 12 months, postoperatively. A total of 495 diabetic vitrectomies, for 404 eyes of 335 patients were performed in SA and NT between 2007 and 2011. 77 (23%) patients requiring diabetic vitrectomy were Indigenous Australians. 87% of patients undergoing diabetic vitrectomy had stable or improved vision at 1 year, postoperatively. There was no significant difference between indigenous and non-indigenous eyes achieving visual success (P = 0.929). Timely preoperative laser treatment (P = 0.03) and preoperative visual acuity (P = 0.01) were the predominant factors associated with visual success. Indigenous patients are just as likely to have improved vision following diabetic vitrectomy as non-Indigenous Australians. However, the small subset of indigenous patients with blind eyes prior to vitrectomy are significantly less likely to improve from surgery. The underlying factors associated with poor outcomes in this group requires further exploration. © 2017 Royal Australian and New Zealand College of Ophthalmologists.
Kumar, Atul; Ravani, Raghav; Mehta, Aditi; Simakurthy, Sriram; Dhull, Chirakshi
2017-07-04
To evaluate the outcomes of pars plana vitrectomy (PPV) with microscope-integrated intraoperative optical coherence tomography (I-OCT)-guided traction removal and center-sparing internal limiting membrane (cs-ILM) peeling. Nine eyes with myopic traction maculopathy as diagnosed on SD-OCT underwent PPV with I-OCT-guided cs-ILM peeling and were evaluated prospectively for resolution of central macular thickness (CMT) and improvement in best-corrected visual acuity (BCVA), and complications, if any, were noted. All patients were followed up for more than 9 months. Resolution of the macular retinoschisis was seen in all nine eyes on SD-OCT. At 36 weeks, there was a significant improvement in mean BCVA from the preoperative BCVA (P = 0.0089) along with a reduction in the CMT from 569.77 ± 263.19 to 166.0 ± 43.91 um (P = 0.0039). None of the eyes showed worsening of BCVA or development of full-thickness macular hole in the intraoperative or follow-up period. PPV with I-OCT-guided cs-ILM peeling helps in complete removal of traction, resolution of retinoschisis and good functional recovery with low intraoperative and postoperative complications.
Preretinal partial pressure of oxygen gradients before and after experimental pars plana vitrectomy.
Petropoulos, Ioannis K; Pournaras, Jean-Antoine C; Stangos, Alexandros N; Pournaras, Constantin J
2013-01-01
To evaluate preretinal partial pressure of oxygen (PO2) gradients before and after experimental pars plana vitrectomy. Arteriolar, venous, and intervascular preretinal PO2 gradients were recorded in 7 minipigs during slow withdrawal of oxygen-sensitive microelectrodes (10-μm tip diameter) from the vitreoretinal interface to 2 mm into the vitreous cavity. Recordings were repeated after pars plana vitrectomy and balanced salt solution (BSS) intraocular perfusion. Arteriolar, venous, and intervascular preretinal PO2 at the vitreoretinal interface were 62.3 ± 13.8, 22.5 ± 3.3, and 17.0 ± 7.5 mmHg, respectively, before vitrectomy; 97.7 ± 19.9, 40.0 ± 21.9, and 56.3 ± 28.4 mmHg, respectively, immediately after vitrectomy; and 59.0 ± 27.4, 25.2 ± 3.0, and 21.5 ± 4.5 mmHg, respectively, 2½ hours after interruption of BSS perfusion. PO2 2 mm from the vitreoretinal interface was 28.4 ± 3.6 mmHg before vitrectomy; 151.8 ± 4.5 mmHg immediately after vitrectomy; and 34.8 ± 4.1 mmHg 2½ hours after interruption of BSS perfusion. PO2 gradients were still present after vitrectomy, with the same patterns as before vitrectomy. Preretinal PO2 gradients are not eliminated after pars plana vitrectomy. During BSS perfusion, vitreous cavity PO2 is very high. Interruption of BSS perfusion evokes progressive equilibration of vitreous cavity PO2 with concomitant progressive return of preretinal PO2 gradients to their previtrectomy patterns. This indicates that preretinal diffusion of oxygen is not altered after vitrectomy. The beneficial effect of vitrectomy in ischemic retinal diseases or macular edema may be related to other mechanisms, such as increased oxygen convection currents or removal of growth factors and cytokines secreted in the vitreous.
An Optical Method for Measuring Injection Timing in Diesel Engines, Using a Single Port
2014-09-01
23 2. Displacement Sensor ..........................................................................24...29 5. Laser ....................................................................................................31 6. Lens- Sensor ...33 b. Sensor ......................................................................................33 c. Filter
Yalinbas, Duygu; Aktas, Zeynep; Hepsen, İbrahim; Dilekmen, Nilay
2017-09-23
To report two cases with an acute vision loss due to intracapsular hemorrhage (hematoma) after an uncomplicated gonioscopy-assisted transluminal trabeculotomy (GATT) combined with phacoemulsification surgery. Case report. Seventy-six-year-old male and 75-year-old female patients with cataract and pseudoexfoliative glaucoma (XFG) uncontrolled with maximum medical therapy both underwent GATT combined with phacoemulsification. Shortly after the surgery, intracapsular hematoma behind the intraocular lens (IOL) were noted in both patients. Hematoma cleared in both of them via IOL extraction-anterior vitrectomy and YAG-laser capsulotomy, respectively. Hematoma cleared in both patients without any surgical complications. Vision loss due to unclearing intracapsular hematoma might be an early complication of combined GATT and phacoemulsification surgery.
SU-F-T-75: Dosimetry Considerations in the Use of Hanging-Eye Block for Lesions of the Conjunctiva
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grelewicz, Z; Lee, B; Cutright, D
Purpose: Superficial lesions in the conjunctiva are frequently treated with en face electrons, using a hanging block to spare dose to the lens of the eye. Dose to the tumor and lens depend on the design and setup of the block and supporting apparatus. We performed in phantom measurements in order to characterize the dose sparing effects of the block as well as the under-dosing effect under the supporting apparatus for 6 MeV treatment. Methods: The commercial hanging block studied uses a 1.2 cm diameter tungsten cylinder supported by a 3 mm diameter acrylic rod. Point dose measurements under themore » hanging block, under an unblocked part of the field, and under the acrylic rod were performed using MOSFET detectors. In addition, EBT3 film was used for both PDD and profile measurements at a depth in phantom of 3 mm for both 105 and 103 cm SSD. Results: MOSFET measurements reported a dose reduction of 95% under the tungsten block when using an SSD of 103 cm, and 86% when using an SSD of 105 cm at a depth in phantom of 3 mm. Film measurements showed that the area under the acrylic rod may be under-dosed by as much as 30% when using 103 SSD. MOSFET measurements confirmed that when using an SSD of 103 cm, the area under the acrylic rod is under-dosed by up to 30% at 3mm depth, compared to the unblocked part of the field. Conclusion: The effectiveness of the commercial hanging block apparatus depends on setup, with 95% lens sparing possible with an SSD of 103 cm. This short SSD is necessary for sharp penumbra. At this SSD, substantial under-dosing under the acrylic support rod is possible. This must be mitigated with either feathering, or using an alternative method of support for the tungsten block.« less
Erdogan, Gurkan; Unlu, Cihan; Karasu, Bugra; Kardes, Esra; Ergin, Ahmet
2016-07-01
To evaluate the efficacy and safety of peripheral vitrectomy under air infusion in comparison with fluid infusion in patients undergoing 23-gauge pars plana vitrectomy for primary rhegmatogenous retinal detachment. A total of 80 eyes of 80 patients with primary rhegmatogenous retinal detachment were enrolled into the study. Forty cases underwent peripheral vitrectomy under air infusion (air group), and a control group of equal number underwent peripheral vitrectomy under fluid infusion (fluid group). Peripheral iatrogenic retinal breaks during peripheral vitrectomy, postoperative visual acuities, and retinal redetachment rates were compared. The number of eyes with peripheral iatrogenic retinal breaks in air group during peripheral vitrectomy was statistically comparable with that in fluid group (1/40 and 4/40, 2.5% and 10%, respectively; P = 0.16). Scleral depression was necessitated in 7 of 40 cases (17.5%) during the operation in the air group. There were no statistically significant differences between the groups in means of postoperative visual acuity and retinal redetachment (P = 0.18 and P = 1.0, respectively). Peripheral vitrectomy under air infusion for primary rhegmatogenous retinal detachment revealed comparable results with fluid infusion in terms of intraoperative and postoperative complications and surgical outcomes.
Postoperative eccentric macular holes after vitrectomy and internal limiting membrane peeling.
Brouzas, Dimitrios; Dettoraki, Maria; Lavaris, Anastasios; Kourvetaris, Dimitrios; Nomikarios, Nikolaos; Moschos, Marilita M
2017-06-01
The purpose of this study was to describe the incidence, clinical characteristics, and outcome of eccentric macular holes presenting after vitrectomy and internal limiting membrane (ILM) peeling for the treatment of macular pathology and discuss the pathogenesis of holes formation. A retrospective, noncomparative, interventional case-series study of five patients who developed eccentric macular holes postoperatively following vitrectomy in 198 consecutive patients who underwent ILM peeling for idiopathic macular hole and epiretinal membrane formation between 2008 and 2015. Five patients (2.5 %) developed full-thickness eccentric macular holes postoperatively. Three patients presented with a single eccentric macular hole, one patient had an eccentric hole after a failed idiopathic macular hole surgery and one patient developed four eccentric macular holes. The mean diameter of the holes was 584 μm (range 206-1317 μm) and the average time of holes formation after vitrectomy was 27.7 weeks (range 1-140 weeks). Postoperative best-corrected visual acuity ranged from "counting fingers" to 20/25. The eyes with the holes distant from the fovea had the best final visual acuity. No further intervention was attempted and no complications occurred. The mean follow-up time was 26.8 months. The postoperative macular holes after vitrectomy and ILM peeling were variable in number, size, and time of appearance but remained stable and were not associated with any complications. The pathogenesis of macular holes is most consistent with contraction of the residual ILM or secondary epimacular proliferation probably stimulated by ILM peeling.
Navarro, Rodrigo M.; Machado, Leonardo M.; Maia, Ossires; Wu, Lihteh; Farah, Michel E.; Magalhaes, Octaviano; Arevalo, J. Fernando; Maia, Mauricio
2015-01-01
Purpose. To determine the efficacy of 23-gauge pars plana vitrectomy (PPV) for symptomatic posterior vitreous detachment (PVD) on visual acuity (VA) and quality after multifocal intraocular lenses (IOLs). Methods. In this prospective case series, patients who developed symptomatic PVD and were not satisfied with visual quality due to floaters and halos after multifocal IOL implantation underwent PPV. Examinations included LogMAR uncorrected visual acuity (UCVA), intraocular pressure, biomicroscopy, and indirect ophthalmoscopy at baseline and 1, 7, 30, and 180 days postoperatively. Ultrasonography and aberrometry were performed. The Visual Functioning Questionnaire 25 (VFQ-25) was administered preoperatively and at 30 days postoperatively. Both the postoperative UCVA and questionnaire results were compared to preoperative findings using the Wilcoxon test. Results. Sixteen eyes of 8 patients were included. VA significantly improved from 0.17 to 0.09 postoperatively (P = 0.017). All patients reported improvement of halos, glare, and floaters. VFQ-25 scores significantly improved in general vision (P = 0.023), near activities (P = 0.043), distance activities (P = 0.041), mental health (P = 0.011), role difficulties (P = 0.042), and driving (P = 0.016). Conclusion. PPV may increase UCVA and quality of vision in patients with bilateral multifocal IOLs and symptomatic PVD. Larger studies are advised. PMID:26504590
Takashina, Hirotsugu; Watanabe, Akira; Tsuneoka, Hiroshi
2017-01-01
To evaluate full-thickness macular hole (MH) formation in the postoperative period after initial vitrectomy for rhegmatogenous retinal detachment (rRD). We retrospectively reviewed the medical records of 4 consecutive eyes that required additional vitrectomy for full-thickness MH between April 2013 and March 2016 after undergoing an initial vitrectomy for rRD. Epiretinal membrane (ERM) was identified by preoperative optical coherence tomography or intraoperative dye staining in each case. Photocoagulation of retinal breaks prior to initial vitrectomy was performed in Cases 1, 2, and 3 (4-16 days), with yttrium-aluminum-garnet capsulotomy after cataract extraction also performed prior to the retinal break formation in Case 3. At the initial vitrectomy, there was a superior retinal break which crossed the equator in Case 2, and an intentional hole was created in Cases 1 and 4. The mean interval from the initial vitrectomy until MH formation was 27.5 ± 15.8 months. As with Case 2, the intervals in Cases 1 and 4, in which an intentional hole was created, were clearly shorter than in those in Case 3. Finally, MH closure was achieved after an additional vitrectomy (removal of the internal limiting membrane with ERM and gas tamponade) and best-corrected visual acuity improved in each case. ERM was identified in the cases examined in our study. The presence of an intentional hole might shorten the interval of MH formation after vitrectomy for rRD.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orman, Amber; Koru-Sengul, Tulay; Miao, Feng
2014-12-01
Purpose/Objective(s): To evaluate the effects of various patient characteristics and radiation therapy treatment variables on outcomes in advanced-stage retinoblastoma. Methods and Materials: This was a retrospective review of 41 eyes of 30 patients treated with external beam radiation therapy between June 1, 1992, and March 31, 2012, with a median follow-up time of 133 months (11 years). Outcome measures included overall survival, progression-free survival, local control, eye preservation rate, and toxicity. Results: Over 90% of the eyes were stage V. Definitive external beam radiation therapy (EBRT) was delivered in 43.9% of eyes, adjuvant EBRT in 22% of eyes, and second-line/salvage EBRT inmore » 34.1% of eyes. A relative lens sparing (RLS) technique was used in 68.3% of eyes and modified lens sparing (MLS) in 24.4% of eyes. Three eyes were treated with other techniques. Doses ≥45 Gy were used in 68.3% of eyes. Chemotherapy was a component of treatment in 53.7% of eyes. The 10-year overall survival was 87.7%, progression-free survival was 80.5%, and local control was 87.8%. White patients had significantly better overall survival than did African-American patients in univariate analysis (hazard ratio 0.09; 95% confidence interval 0.01-0.84; P=.035). Toxicity was seen in 68.3% of eyes, including 24.3% with isolated acute dermatitis. Conclusions: External beam radiation therapy continues to be an effective treatment modality for advanced retinoblastoma, achieving excellent long-term local control and survival with low rates of treatment-related toxicity and secondary malignancy.« less
Double Internal Limiting Membrane Insertion for Macular Hole-Associated Retinal Detachment
Chen, San-Ni
2017-01-01
Purpose To describe a modified technique of internal limiting membrane (ILM) insertion for macular hole- (MH-) associated retinal detachment (RD) in highly myopic eyes. Methods Nine eyes underwent pars plana vitrectomy, cortical vitreous removal, and fovea-sparing ILM peeling. Double ILM insertion into the hole was performed with inverted perifoveal ILM and a free ILM flap followed by air-fluid exchange. Results Two of the 9 eyes had perifoveal ILM partially torn after cortical vitreous or epiretinal removal. All eyes had the ILM plug stabilized within the MH after double ILM insertion. Postoperatively, MH was sealed with the retina reattached in all the eyes. Conclusion Double ILM insertion may further secure the ILM flap in place in the eyes with MH-associated RD, especially in cases in which insufficient perifoveal ILM was left. This trial is registered with the clinical registration number Clinicaltrials.gov NCT03174639. PMID:28845304
Retinal detachment following endophthalmitis.
Nelsen, P T; Marcus, D A; Bovino, J A
1985-08-01
Fifty-five consecutive patients with a clinical diagnosis of bacterial endophthalmitis were reviewed. All patients were treated with systemic, periocular, topical, and intravitreal antibiotics. In addition, 33 of the patients underwent a pars plana vitrectomy. Nine retinal detachments occurred within six months of initial diagnosis. The higher frequency of retinal detachment in the vitrectomy group (21%) as compared to those patients managed without vitrectomy (9%) may be explained by a combination of surgical complications and the increased severity of endophthalmitis in the vitrectomy group. The two patients who developed retinal detachment during vitrectomy surgery rapidly progressed to no light perception. Conversely, the repair of retinal detachments diagnosed postoperatively had a good prognosis.
34. PRIMARY FLIGHT CONTROL STATION AFT LOOKING FORWARD ON ...
34. PRIMARY FLIGHT CONTROL STATION - AFT LOOKING FORWARD ON PORT SIDE SHOWING FLIGHT DECK LIGHTING BOARD, ARRESTING GEAR CONTROL CONSOLE AND FRESNEL LENS OPTICAL LANDING SYSTEM. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Dauer, Lawrence T; Ainsbury, Elizabeth A; Dynlacht, Joseph; Hoel, David; Klein, Barbara E K; Mayer, Donald; Prescott, Christina R; Thornton, Raymond H; Vano, Eliseo; Woloschak, Gayle E; Flannery, Cynthia M; Goldstein, Lee E; Hamada, Nobuyuki; Tran, Phung K; Grissom, Michael P; Blakely, Eleanor A
2017-10-01
This review summarizes the conclusions and recommendations of the new National Council on Radiation Protection and Measurements (NCRP) Commentary No. 26 guidance on radiation dose limits for the lens of the eye. The NCRP addressed radiation protection principles in respect to the lens of the eye, discussed the current understanding of eye biology and lens effects, reviewed and evaluated epidemiology, and assessed exposed populations with the potential for significant radiation exposures to the lens while suggesting monitoring and protection practices. Radiation-induced damage to the lens of the eye can include the loss of clarity resulting in opacification or clouding several years after exposure. The impact is highly dependent on the type of radiation, how the exposure of the lens was delivered, the genetic susceptibilities of the individual exposed, and the location of the opacity relative to the visual axis of the individual. The preponderance of epidemiological evidence suggests that lens damage could occur at lower doses than previously considered and the NCRP has determined that it is prudent to reduce the recommended annual lens of the eye occupational dose limit from an equivalent dose of 150 mSv to an absorbed dose of 50 mGy. Significant additional research is still needed in the following areas: comprehensive evaluation of the overall effects of ionizing radiation on the eye, dosimetry methodology and dose-sparing optimization techniques, additional high quality epidemiology studies, and a basic understanding of the mechanisms of cataract development.
Longitudinal Coupled-Bunch Instability Around 1 GHz at the CERN PS Booster
NASA Astrophysics Data System (ADS)
Schönauer, H.; Caspers, F.; Chanel, M.; Soby, L.; D'Yachkov, M.
1997-05-01
The fast-growing "Ring 4" instability occurring at intensities above 6.5 10^12 protons in the top one of the four PSB rings is finally explained by an asymmetry in the 42 vacuum pump manifolds common to all rings. Impedance measurements (wire method) and numerical calculations show a sharp resonant peak (Q 2000) at 1100 MHz and shunt impedances two times higher for the Ring 4 ports as compared to the other rings. This factor is sufficient to explain that the threshold of the instability falls below the maximum intensity only in Ring 4. A final, but labour-intensive and expensive, cure consists of inserting short-circuiting sleeves into all 168 beam ports. A temporary antidote is attempted by fitting ceramic damping resistors penetrating the top cavity through spare gauge ports. Results of beam and impedance measurements and of the cure will be presented and discussed.
Osteo-odonto-keratoprosthesis for end-stage cornea blindness.
Wong, H S; Then, K Y; Ramli, R
2011-10-01
We report the first case of Osteo-odonto-keratoprosthesis (OOKP) who successfully underwent surgery in Malaysia following a grade 4 (severe) chemical injury in both eyes in 2006. The patient's left eye was eviscerated and his right eye underwent penetrating keratoplasty. However, the corneal graft failed and became opaque. His right eye could only perceive light. The OOKP was offered to him hoping to recover some functional vision. He underwent a 2-stage surgery to implant the OOKP into his right eye. However, 2 months post-operation, he developed vitreous haemorrhage. A successful pars plana vitrectomy (PPV) was performed via the limited view through the lens. He attained a final visual acuity of 6/60 (N36). He was able to mobilize more independently, feed, dress himself and read large print.
VITRECTOMY FOR MACULAR RETINOSCHISIS WITHOUT A DETECTABLE OPTIC DISK PIT.
Haruta, Masatoshi; Yamakawa, Ryoji
2017-05-01
To evaluate the efficacy of vitrectomy in the treatment of macular retinoschisis without a detectable optic disk pit. This retrospective interventional case series included eight patients with acquired, unilateral macular retinoschisis with or without foveal detachment. Patients with an optic disk pit, vitreomacular traction, or high myopia were excluded. Six of the eight patients underwent vitrectomy with internal limiting membrane peeling and fluid-air exchange. The surgical outcome was evaluated in terms of the improvement in the macular anatomy and the best-corrected visual acuity. During vitrectomy, all the six eyes were confirmed to have preexisting posterior vitreous detachment. Macular retinoschisis was resolved or reduced in all the six eyes after vitrectomy. The mean central foveal thickness showed significant improvement at the time of the patient's final visit after vitrectomy. The mean best-corrected visual acuity was 20/52 before surgery and 20/31 at the final visit. Vitrectomy might be effective for the treatment of macular retinoschisis without an optic disk pit. Although clinically similar to optic pit maculopathy except for the absence of pit, our intraoperative observations of the posterior hyaloid membrane suggest that maculopathy without optic disk pit has a distinct pathogenesis.
Yamamoto, Kaori; Hori, Sadao
2011-01-01
To elucidate the long-term outcome of internal limiting membrane (ILM) peeling on visual function during vitrectomy for idiopathic macular holes using scanning laser ophthalmoscope (SLO) microperimetry. Prospective uncontrolled study. We studied 31 eyes (29 patients) with idiopathic macular holes. All patients underwent vitrectomy with ILM peeling. The SLO microperimetry was performed preoperatively, and once a year for 3 years postoperatively to detect scotomas in and around the macular holes, and both within and in close vicinity to the areas of ILM peeling. Closure of macular holes after one surgery was confirmed in all cases except for 2 with second surgery. The visual acuity by logarithmic minimum angle of resolution (logMAR) averaged 0.71 +/- 0.36 before surgery, 0.23 +/- 0.31 one year, 0.14 +/- 0.27 two years and 0.12 +/- 0.26 three years after surgery. There was significant improvement up to 2 years after the surgery. All scotomas detected before surgery in the holes, and 77.4% of those detected around the holes decreased gradually. No scotomas were detected in or around the area of ILM peeling either before or after surgery. ILM peeling in vitrectomy for idiopathic macular holes successfully improved visual acuity and did not influence retinal sensitivity in and around the area of ILM peeling. The scotomas detected in and around the holes before surgery gradually reduced or disappeared.
Moradian, Siamak; Ahmadieh, Hamid; Faghihi, Hooshang; Ramezani, Alireza; Entezari, Morteza; Banaee, Touka; Heidari, Ebadollah; Behboudi, Hassan; Yasseri, Mehdi
2016-09-01
To compare the visual and anatomical outcomes of four surgical techniques to manage pseudophakic and aphakic retinal detachment (PARD). In a multicenter randomized clinical trial, 211 eyes of 211 patients with PARD and proliferative vitreoretinopathy (PVR) grade B or less were randomly assigned to one of the four treatment groups: (1) scleral buckling (SB), 50 eyes, (2) vitrectomy without band, 51 eyes, (3) vitrectomy with encircling band (EB), 58 eyes, and (4) triamcinolone acetonide (TA) assisted vitrectomy, 52 eyes. Patients were followed for 12 months after the surgery. The best-corrected visual acuity (BCVA) and retinal reattachment rate at each follow-up time point were considered as the primary outcome measures. PVR, macular pucker, and cystoid macular edema were considered as the secondary outcomes. Visual improvement was achieved in all treatment groups relative to the baseline at all time points (all Ps < 0.001). There were no statistically significant differences among the groups with regard to BCVA changes. However, there was a significant difference in the slope of visual improvement curve: the SB group had a more rapid visual improvement compared to the vitrectomy with buckle group at month 12 (P = 0.032). The retinal reattachment rates at month 12 were 75, 64.7, 68.5, and 66.7 % in SB, vitrectomy without buckle, vitrectomy with EB, and TA-assisted vitrectomy groups respectively (P > 0.99). There were no statistically significant differences among the groups in terms of adverse events. SB, TA-assisted vitrectomy, and vitrectomy with and without buckle had comparable outcomes in the management of PARD.
6. Oblique view from liftbed truck, showing northwest and southwest ...
6. Oblique view from lift-bed truck, showing northwest and southwest facades; projecting hip roof section supported by masonry pillars marks location of former porte cochere, removed in 1937; that portion wall beneath this roof section, containing visible double doors, is of frame and stucco construction, scored and tinted to imitate sandstone masonry; interior space formed by this enclosure of portion of former porte cochere now contains restrooms; view to southeast, 65mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA
Dinh, Jeffrey; Stoker, Joshua; Georges, Rola H; Sahoo, Narayan; Zhu, X Ronald; Rath, Smruti; Mahajan, Anita; Grosshans, David R
2013-12-17
For treatment of the entire cranium using passive scattering proton therapy (PSPT) compensators are often employed in order to reduce lens and cochlear exposure. We sought to assess the advantages and consequences of utilizing compensators for the treatment of the whole brain as a component of craniospinal radiation (CSI) with PSPT. Moreover, we evaluated the potential benefits of spot scanning beam delivery in comparison to PSPT. Planning computed tomography scans for 50 consecutive CSI patients were utilized to generate passive scattering proton therapy treatment plans with and without Lucite compensators (PSW and PSWO respectively). A subset of 10 patients was randomly chosen to generate scanning beam treatment plans for comparison. All plans were generated using an Eclipse treatment planning system and were prescribed to a dose of 36 Gy(RBE), delivered in 20 fractions, to the whole brain PTV. Plans were normalized to ensure equal whole brain target coverage. Dosimetric data was compiled and statistical analyses performed using a two-tailed Student's t-test with Bonferroni corrections to account for multiple comparisons. Whole brain target coverage was comparable between all methods. However, cribriform plate coverage was superior in PSWO plans in comparison to PSW (V95%; 92.9 ± 14 vs. 97.4 ± 5, p < 0.05). As predicted, PSWO plans had significantly higher lens exposure in comparison to PSW plans (max lens dose Gy(RBE): left; 24.8 ± 0.8 vs. 22.2 ± 0.7, p < 0.05, right; 25.2 ± 0.8 vs. 22.8 ± 0.7, p < 0.05). However, PSW plans demonstrated no significant cochlear sparing vs. PSWO (mean cochlea dose Gy(RBE): 36.4 ± 0.2 vs. 36.7 ± 0.1, p = NS). Moreover, dose homogeneity was inferior in PSW plans in comparison to PSWO plans as reflected by significant alterations in both whole brain and brainstem homogeneity index (HI) and inhomogeneity coefficient (IC). In comparison to both PSPT techniques, multi-field optimized intensity modulated (MFO-IMPT) spot scanning treatment plans displayed superior sparing of both lens and cochlea (max lens: 12.5 ± 0.6 and 12.9 ± 0.7 right and left respectively; mean cochlea 28.6 ± 0.5 and 27.4 ± 0.2), although heterogeneity within target volumes was comparable to PSW plans. For PSPT treatments, the addition of a compensator imparts little clinical advantage. In contrast, the incorporation of spot scanning technology as a component of CSI treatments, offers additional normal tissue sparing which is likely of clinical significance.
Posterior chamber lens implantation with scleral fixation in children with traumatic cataract.
Caca, Ihsan; Sahin, Alparslan; Ari, Seyhmus; Alakus, Fuat
2011-01-01
To evaluate the outcomes of posterior chamber lens implantation with scleral fixation (SF-PCIOL) in children with traumatic cataract. Twenty-four eyes of 24 cases were included. All patients had corneal or corneoscleral lacerations that were primarily repaired. Traumatic cataract subsequently developed and SF-PCIOL was performed due to insufficient posterior capsule support. The average age of the patients was 5.8 years (range: 4 to 10 years). All cases had SF-PCIOL implanted via internal route using triangular double scleral flaps made of 9-0 polypropylene after a complete anterior vitrectomy. Average follow-up was 14.6 ± 4.3 months (range: 11 to 18 months). Visual acuity was increased at the last visit in 23 (96%) patients. Common postoperative complications were fibrinous reaction in 6 (25%) patients, transient intraocular pressure increase in 4 (17%) patients, membrane formation requiring removal in 1 (4%) patient, transient intraocular hemorrhage as vitreous hemorrhage in 1 (4%) patient, and retinal detachment in 1 (4%) patient after the postoperative second month. SF-PCIOL is an effective and reliable method in patients with pediatric traumatic cataract who had insufficient posterior capsule support. Copyright 2011, SLACK Incorporated.
A Further Examination of Operational Availability in Life Cycle Cost Models
1984-09-01
FI) (F3) (F40) where: FI is the number of aircraft ( PfA ) F3 is flying hours per PAA per year ( FH/PAAY’R ) F40 is replenishment spares cost per flying... Salem (ir’eg O 97302 UNCLASSUIEXD SECUI..JTY C -Ab.IFIA) ION OF ’.’HS PAGE RE PORT DOCUMENTATION PAGE~ la, REPORT SECURITY CLASSI (ICArION lb
SU-F-T-659: Nanoparticle-Aided Eye Plaque Radiotherapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chin, J; Ngwa, W
Purpose: Eye plaque brachytherapy is one of the approaches for radiotherapy treatment for ocular cancers: retinoblastoma and choroidal melanoma. This study, investigates the potential benefits of using gold nanoparticles to enhance therapeutic efficacy during eye plaque brachytherapy. Methods: The EYE PHYSICS Inc. Plaque Simulator program distributed by IsoAid, LLC, Port Richey, Florida was used. It is based on the superposition of dose contributions from individual seeds following the TG–43 formalism. Dose enhancement factor (DEF) values for feasible nanoparticle concentrations from previous studies was used to investigate the benefit of using nanoparticles to enhance dose to tumour or reduce dose tomore » healthy tissue. The dose enhancement factor (DEF) represents the ratio of the dose deposited in tumour with nanoparticles divided by dose deposited in the tumour without nanoparticles. The investigation was done for I–125 and Pd–103 typical sources employed for eye plaque brachytherapy. The prescription dose used is 85 Gy. Results: Lower dose enhancement values were obtained for Pd–103. With DEF of 2 due to gold nanoparticles, critical structure doses reduce by a factor of 2. Optic disc dose is 6.69 Gy and 4.571 Gy, opposite retina dose is 4.064 and 2.484 Gy, lens dose is 12.66 Gy and 9.870 Gy, and fovea dose is 9.85 Gy and 7.275 Gy. With DEF of 3 due to gold nanoparticles, critical structure doses reduce by a factor of 3. Optic disc dose is 4.352 Gy and 2.975 Gy, opposite retina dose is 2.644 Gy and 1.618 Gy, lens dose is 8.322 Gy and 6.427 Gy, and fovea dose is 4.815 Gy and 4.737 Gy. Conclusion: The results of this research predict that using gold nanoparticles will lead to major sparing of dose to critical structures. The finding provides more impetus for the development of nanoparticle–aided brachytherapy.« less
Perfluorocarbon perfused vitrectomy: animal studies.
Quiroz-Mercado, Hugo; Suarez-Tatá, Luis; Magdalenic, Rudi; Murillo-López, Sergio; García-Aguirre, Gerardo; Guerrero-Naranjo, Jose; Rodríguez-Reyes, Abelardo A
2004-02-01
To investigate the feasibility and advantages of using perfluorocarbon liquid (PCL) perfusion to remove vitreous during suction-cutting vitrectomy in rabbit and pig eyes. Experimental study. Balanced salt solution (BSS) was replaced by PCL perfusion during experimental vitrectomy. Oxygenated or nonoxygenated PCL was used in a recycling or a nonrecycling system. Recycling was achieved by two systems: a manual recycling system or a closed-loop system. The experiments in this study consisted of: an in vitro solubility observation, safety and feasibility of vitrectomy in rabbit eyes, effectiveness of vitrectomy with equal vitrectomy time in rabbit eyes, and retinal stability and pigment and blood dispersion in porcine eyes. Toxicity was assessed by a complete ophthalmic examination, endothelial cell count, electroretinography, and histopathology. Vitreous, blood, and pigments were immiscible in PCL. Manual recycling required less amounts of PCL than nonrecycling (15 vs 25 cc). Oxygenated and nonoxygenated PCL were not toxic. Perfluorocarbon liquid infusion removed more vitreous than balanced salt solution in a 3-minute vitrectomy time using the same settings on the vitrectomy machine. The PCL infusion in porcine eyes stabilized the retina and isolated vitreous cavity from pigment and blood and maintained a clear vitreous cavity. These data indicate that perfusion of PCL can be used to remove vitreous with a suction-cutting probe in rabbit and pig eyes. Retinal stability and isolation of the vitreous cavity at the time of vitreous removal along with PCL immiscibility and its specific gravity suggest that PCL has a potential clinical use as an irrigating solution to remove vitreous.
Matsumura, Takehiro; Takamura, Yoshihiro; Tomomatsu, Takeshi; Arimura, Shogo; Gozawa, Makoto; Takihara, Yuji; Inatani, Masaru
2015-06-01
Previous studies indicate involvement of matrix metalloproteinases (MMPs) in the pathogenesis of diabetic keratopathy. To evaluate MMP levels in the tears of patients with diabetes, we investigated changes in MMP levels during perioperative periods and clarify the relationship with corneal epithelial disorders following vitrectomy. Matrix metalloproteinase levels in tears were measured by multiplex bead array in patients with or without diabetes who were scheduled for vitrectomy. Twenty-two patients with diabetes and proliferative diabetic retinopathy, and 20 patients with epiretinal membrane or macular hole (control group), were recruited. Changes in MMP levels during perioperative periods and the relationship with corneal epithelial disorders after vitrectomy were analyzed. The levels of MMP-2, -9, and -10 at 1 day after surgery in the diabetic group were significantly higher than in the control group. At 1 week after surgery, MMP-10 levels in the diabetic group were significantly higher than in the control group. After vitrectomy, corneal epithelial disorders occurred in six patients in the diabetic group but not in the control group. In the diabetic group, MMP-10 levels in tears of patients with corneal epithelial disorders were significantly higher than those in patients without corneal epithelial disorders. The MMP concentration in tears of patients with diabetes was higher than in nondiabetic patients after vitrectomy. High MMP-10 levels were observed in patients with diabetes and corneal epithelial disorders after vitrectomy. Aberrant levels of MMP-10 may cause corneal epithelial disorder after vitrectomy.
Capolicchio, J-P; Feifer, A; Plante, M K; Tchervenkov, J
2011-01-01
The retroperitoneoscopic (RP) approach to live donor nephrectomy (LDN) may be advantageous for the donor because it avoids mobilization of peritoneal organs and provides direct access to the renal vessels. Notwithstanding, this approach is not popular, likely because of the steeper learning curve. We feel that hand-assistance (HA) can reduce the learning curve and in this study, we present our experience with a novel hand-assist approach to retroperitoneoscopic live donor nephrectomy (HARP-LDN). Over a one-yr period, 10 consecutive patients underwent left HARP-LDN with a mean body mass index of 29 and three with prior left abdomen surgery. The surgical technique utilizes a 7 cm, muscle-sparing incision for the hand-port with two endoscopic ports. Operative time was an average of 155 min., with no open conversions. Mean blood loss was 68 mL, and warm ischemia time was 2.5 min. Hospital stay averaged 2.7 d with postoperative complications limited to one urinary retention. Our modified HARP approach to left LDN is safe, effective and can be performed expeditiously. Our promising initial results require a larger patient cohort to confirm the advantages of the hand-assisted retroperitoneal technique. © 2010 John Wiley & Sons A/S.
Constellation Architecture Team-Lunar: Lunar Habitat Concepts
NASA Technical Reports Server (NTRS)
Toups, Larry; Kennedy, Kriss J.
2008-01-01
This paper will describe lunar habitat concepts that were defined as part of the Constellation Architecture Team-Lunar (CxAT-Lunar) in support of the Vision for Space Exploration. There are many challenges to designing lunar habitats such as mission objectives, launch packaging, lander capability, and risks. Surface habitats are required in support of sustaining human life to meet the mission objectives of lunar exploration, operations, and sustainability. Lunar surface operations consist of crew operations, mission operations, EVA operations, science operations, and logistics operations. Habitats are crewed pressurized vessels that include surface mission operations, science laboratories, living support capabilities, EVA support, logistics, and maintenance facilities. The challenge is to deliver, unload, and deploy self-contained habitats and laboratories to the lunar surface. The CxAT-Lunar surface campaign analysis focused on three primary trade sets of analysis. Trade set one (TS1) investigated sustaining a crew of four for six months with full outpost capability and the ability to perform long surface mission excursions using large mobility systems. Two basic habitat concepts of a hard metallic horizontal cylinder and a larger inflatable torus concept were investigated as options in response to the surface exploration architecture campaign analysis. Figure 1 and 2 depicts the notional outpost configurations for this trade set. Trade set two (TS2) investigated a mobile architecture approach with the campaign focused on early exploration using two small pressurized rovers and a mobile logistics support capability. This exploration concept will not be described in this paper. Trade set three (TS3) investigated delivery of a "core' habitation capability in support of an early outpost that would mature into the TS1 full outpost capability. Three core habitat concepts were defined for this campaign analysis. One with a four port core habitat, another with a 2 port core habitat, and the third investigated leveraging commonality of the lander ascent module and airlock pressure vessel hard shell. The paper will describe an overview of the various habitat concepts and their functionality. The Crew Operations area includes basic crew accommodations such as sleeping, eating, hygiene and stowage. The EVA Operations area includes additional EVA capability beyond the suit-port airlock function such as redundant airlock(s), suit maintenance, spares stowage, and suit stowage. The Logistics Operations area includes the enhanced accommodations for 180 days such as closed loop life support systems hardware, consumable stowage, spares stowage, interconnection to the other Hab units, and a common interface mechanism for future growth and mating to a pressurized rover. The Mission & Science Operations area includes enhanced outpost autonomy such as an IVA glove box, life support, and medical operations.
Ocular blood flow parameters after pars plana vitrectomy in patients with diabetic retinopathy.
Krepler, Katharina; Polska, Elzbieta; Wedrich, Andreas; Schmetterer, Leopold
2003-04-01
Whereas the anatomic result of vitrectomy in patients with vitreoretinal complications due to diabetes is usually satisfying, the functional outcome is sometimes poor. The authors investigated whether this may be related in part to effects of vitrectomy on ocular perfusion. Ocular hemodynamics were measured before vitrectomy and 1 and 4 weeks postoperatively in 13 consecutive diabetic patients. Pulsatile choroidal blood flow was assessed with laser interferometric measurement of fundus pulsation amplitude. In addition, mean blood flow velocity and resistive index in the ophthalmic artery, the central retinal artery, and the posterior ciliary arteries were measured with color Doppler imaging. Fundus pulsation amplitude was significantly reduced after surgery as compared to baseline (baseline: 3.7 +/- 1.0 microm; 4 weeks: 3.1 +/- 0.8; P < 0.001). Postoperatively, mean blood flow velocity in the central retinal artery (P = 0.009) and the posterior ciliary arteries (P = 0.0006) was significantly reduced, whereas resistive index was increased in the central retinal artery (P = 0.028) but not in the posterior ciliary arteries. The current data suggest that vitrectomy induces significant reductions in ocular blood flow in patients with diabetic retinopathy. Whether this may affect the visual outcome after vitrectomy or whether this reflects improved retinal oxygenation after vitrectomy remains to be established.
Shahzadi, Bashiran; Rizwi, Syed Fawad; Qureshi, Faisal Murtaza; Latif, Kanwal; Mahmood, Syed Asaad
2017-01-01
Objective: To evaluate the visual outcomes of 27-gauge transconjunctival sutureless vitrectomy surgery and its complications in patients with diabetic vitreous hemorrhage. Methods: A quasi-experimental study was conducted where eighty seven eyes of 87 uncontrolled type II diabetes mellitus patients presenting with diabetic vitreous hemorrhage were selected to undergo 27-gauge transconjunctival sutureless micro-incision vitrectomy surgery. Main outcome measured was best corrected visual acuity (BCVA). Post-operative complications were also screened for at each visit. The follow ups were at post-operative day one, one month, three months and six months respectively. Results: Out of 87 patients, 52 (59.8%) were males and 35 (40.2%) were females. The mean age of the patients was 52.32 ± 6.78 years (95% CI: 53.13 - 55.57). For most of the patients, the BCVA improved progressively with each subsequent follow up visit. Pre-operative BCVA was 1.01 ± 0.206 logMar, compared to BCVA at final follow up of 0.44 ± 0.231 (p-value < 0.001). Six (6.9%) patients developed recurrent vitreous hemorrhage during the study period, four (4.6%) developed cataract, one (1.1%) had increased intraocular pressure and sub conjunctival hemorrhage was present in two (2.3%). Conclusion: 27-gauge micro-incision vitrectomy surgery is an effective sutureless surgery with favorable outcomes, in terms of vision, in patients with diabetic vitreous hemorrhage. The associated complications are few which can be easily managed. PMID:28367178
Radial retinotomy in the macula.
Bovino, J A; Marcus, D F
1984-01-01
Radial retinotomy is an operative procedure usually performed in the peripheral or equatorial retina. To facilitate retinal attachment, the authors used intraocular scissors to perform radial retinotomy in the macula of two patients during vitrectomy surgery. In the first patient, a retinal detachment complicated by periretinal proliferation and macula hole formation was successfully reoperated with the aid of three radial cuts in the retina at the edges of the macular hole. In the second patient, an intraoperative retinal tear in the macula during diabetic vitrectomy was also successfully repaired with the aid of radial retinotomy. In both patients, retinotomy in the macula was required because epiretinal membranes, which could not be easily delaminated, were hindering retinal reattachment.
Elder, Mark J; Morlet, Nigel
2002-12-01
Australia and New Zealand continue to be at the forefront of endophthalmitis research. In this Clinical Controversy, an ophthalmologist from each country presents different approaches to the management of a 72-year-old patient with routine endophthalmitis following cataract surgery. Mark Elder concludes that this case needs aqueous and vitreous aspirates for culture and the initial treatment of choice is intracameral vancomycin and amikacin. The evidence for intravitreal steroids is equivocal. Systemic antibiotics are indicated if there is a possibility of a bacterial biofilm present on the intraocular lens. Nigel Morlet concludes that timely intervention with appropriate antibiotics delivered in the right concentration to the vitreous cavity is the crux of successful management of endophthalmitis. Aggressive treatment of the inflammatory response is also required to further reduce the damage to the intraocular structures. Both ophthalmologists agree that vitrectomy is not necessarily the most appropriate treatment option.
A case of perforating injury of eyeball and traumatic cataract caused by acupuncture.
Shuang, Han; Yichun, Kong
2016-04-01
Perforating globe injury is the leading cause of monocular blindness and vision loss. A 58-year-old male was injured by acupuncture needle during acupuncture treatment for his cerebral infarction. To the best of our knowledge, this is the first case report of perforating injury of the eyeball and traumatic cataract caused by acupuncture. The patient was hospitalized due to diagnosis of perforating ocular injury, traumatic cataract, and corneal and iris perforating injury. Moreover, he had to accept treatments of phacoemulsification, anterior vitrectomy along with intraocular lens implantation in the sulcus to improve his visual acuity. As acupuncture therapy has been widely performed for various diseases and achieved highly approval, the aim of this report is to remind acupuncturists operating accurately to avoid unnecessary injury during the treatment process, or the cure can also become the weapon.
Endophthalmitis following pars plana vitrectomy for vitreous floaters
Henry, Christopher R; Schwartz, Stephen G; Flynn, Harry W
2014-01-01
A case of Staphylococcus caprae endophthalmitis in a young patient following pars plana vitrectomy for symptomatic vitreous floaters is reported here. Recent literature suggests that there is an increasing trend of performing pars plana vitrectomy for symptomatic floaters. Although rare, the potential risk of endophthalmitis should be explicitly discussed with patients considering surgical intervention for vitreous floaters. PMID:25210434
Endophthalmitis following pars plana vitrectomy for vitreous floaters.
Henry, Christopher R; Schwartz, Stephen G; Flynn, Harry W
2014-01-01
A case of Staphylococcus caprae endophthalmitis in a young patient following pars plana vitrectomy for symptomatic vitreous floaters is reported here. Recent literature suggests that there is an increasing trend of performing pars plana vitrectomy for symptomatic floaters. Although rare, the potential risk of endophthalmitis should be explicitly discussed with patients considering surgical intervention for vitreous floaters.
Treatment of endophthalmitis by pars plana vitrectomy.
Verbraeken, H; Geeroms, B; Karemera, A
1988-01-01
Between 1976 and 1985 81 cases of endophthalmitis have been treated by pars plana vitrectomy and intravitreous injection of antibiotics or antimycotics. The functional results and the etiology of the endophthalmitis are discussed, as well as the reasons to perform a vitrectomy in endophthalmitis, and a possible explanation for the relatively high incidence of pseudophakic endophthalmitis is given.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, B; Kim, J
Purpose: To compare the dosimetry of coplanar and non-coplanar RapidArc whole brain plans for hippocampal sparing Methods: We studied the RapidArc plans of patient with brain metastases, with the prescription of 3750 cGy in 15 fractions. The coplanar approach used a full clockwise (CW) arc and a full counterclockwise (CCW) arc, with the couch angle to be 0°. The non-coplanar approach used a full arc with a couch angle of 0°, and a partial arc with a couch angle of 90°. Treatment planning system is Eclipse Ver. 11. Constraints for eyes, lens, brainstem, optical nerves and chiasm are employed inmore » the optimization so that these OARs’ dose are below tolerance. Constraints for hippocampus are employed so that they receive dose as low as possible while maintain good coverage to whole brain. The beam delivery machine is Varian 21 IX. T1-weighted MRI images were used for hippocampus contouring. Results: The target coverage index for coplanar and non-coplanar RapidArc plans are 94.9% and 95.4%, respectively, with homogeneity index of 0.223 vs 0.226, which is defined as (D2% – D98%)/Dmean of target volume. V95 and V100 are 99.0% and 94.8% for coplanar plan, vs 99.1% and 95.4% for non-coplanar plan, while the mean dose of hippocampus are 1244.5 cGy for coplanar plan vs 1212.3 cGy for non-coplanar plan. Dose for eyes, lens, optical nerves, optical chiasm and brainstem are all below tolerance. Conclusion: Coplanar RapidArc plan provides good target coverage while achieves good hippocampal sparing, and there is no benefit to use non-coplanar approach.« less
Aptel, Florent; Colin, Cyrille; Kaderli, Sema; Deloche, Catherine; Bron, Alain M; Stewart, Michael W; Chiquet, Christophe
2017-11-01
Prevention and management of postoperative ocular inflammation with corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) have been evaluated in several randomised controlled trials (RCTs). However, neither consensus regarding the efficacies of different regimens nor established guidelines are currently available. This has resulted in different practice patterns throughout the world. A systematic literature review found that for the management of postcataract inflammation nepafenac produced a positive outcome in three of three RCTs (3/3), as did ketorolac (1/1), bromfenac (7/7), loteprednol (3/3) and difluprednate (6/6), but not flurbiprofen (0/1). A single study found that betamethasone produced inconclusive results after retinal detachment (RD) surgery; ketorolac was effective (1/1) after vitrectomy, but triamcinolone was ineffective (0/1) after trabeculectomy. A two-round Delphi survey asked 28 international experts to rate both the inflammatory potential of different eye surgeries and their agreement with different treatment protocols. They rated trabeculectomy, RD surgery and combined phacovitrectomy as more inflammatory than cataract surgery. Vitrectomies for macular hole or epiretinal membrane were not deemed more inflammatory than cataract surgery. For trabeculectomy, they preferred to treat longer than for cataract surgery (NSAID + corticosteroid three times a day for 2 months vs 1 month). For vitrectomy alone, RD surgery and combined phacovitrectomy, the panel preferred the same treatment as for cataract surgery (NSAID + corticosteroid three times a day for 1 month). The discrepancy between preferred treatment and perception of the eye's inflammatory status by the experts for RD and combined vitreoretinal surgeries highlights the need for RCTs to establish treatment guidelines. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
2001-08-06
KENNEDY SPACE CENTER, Fla. -- In the Space Station Processing Facility under the gaze of a worker (far right), the Expedition Three crew look over an Electronic Control Unit. From left are Commander Frank Culbertson and cosmonauts Mikhail Tyurin and Vladimir Dezhurov. The STS-105 mission payload includes the Early Ammonia Servicer (EAS), Multi-Purpose Logistics Module Leonardo and various experiments attached on the port and starboard adapter beams. The EAS contains spare ammonia for the Station’s cooling system. Ammonia is the fluid used in the radiators that cool the Station’s electronics. The EAS will be installed on the P6 truss holding the giant U.S. solar arrays, batteries and cooling radiators. Leonardo is filled with laboratory racks of science equipment and racks and platforms of experiments and supplies. Discovery is scheduled to be launched Aug. 9, 2001
2001-08-06
KENNEDY SPACE CENTER, Fla. -- In the Space Station Processing Facility, the Expedition Three crew (right) listen to a worker discuss solar panels seen here on a workstand. The crew members are (left to right) Commander Frank Culbertson and cosmonauts Mikhail Tyurin and Vladimir Dezhurov. The STS-105 payload includes the Early Ammonia Servicer (EAS), Multi-Purpose Logistics Module Leonardo and various experiments attached on the port and starboard adapter beams. The EAS contains spare ammonia for the Station’s cooling system. Ammonia is the fluid used in the radiators that cool the Station’s electronics. The EAS will be installed on the P6 truss holding the giant U.S. solar arrays, batteries and cooling radiators. Leonardo is filled with laboratory racks of science equipment and racks and platforms of experiments and supplies. Discovery is scheduled to be launched Aug. 9, 2001
Dual Check Valve and Method of Controlling Flow Through the Same
NASA Technical Reports Server (NTRS)
Corallo, Roger (Inventor)
2016-01-01
A dual check valve includes, a housing having a cavity fluidically connecting three ports, a movable member movably engaged within the cavity from at least a first position occluding a first port of the three ports, a second position occluding a second port of the three ports, and a third position allowing flow between both the first port, the second port and a third port of the three ports.
Cruz-Iñigo, Yousef J; Acabá, Luis A; Berrocal, Maria H
2014-01-01
Current indications for pars plana vitrectomy in patients with proliferative diabetic retinopathy (PDR) include vitreous hemorrhage, tractional retinal detachment (TRD), combined tractional and rhegmatogenous retinal detachment (CTRRD), diabetic macular edema associated with posterior hyaloidal traction, and anterior segment neovascularization with media opacities. This chapter will review the indications, surgical objectives, adjunctive pharmacotherapy, microincision surgical techniques, and outcomes of diabetic vitrectomy for PDR, TRD, and CTRRD. With the availability of new microincision vitrectomy technology, wide-angle microscope viewing systems, and pharmacologic agents, vitrectomy can improve visual acuity and achieve long-term anatomic stability in eyes with severe complications from PDR. © 2014 S. Karger AG, Basel
25G compared with 20G vitrectomy under Resight non-contact wide-angle lenses for Terson syndrome.
Mao, Xinbang; You, Zhipeng
2017-08-01
The aim of the present study was to compare the effectiveness of 25G vitrectomy to standard 20G vitrectomy for treatment of Terson syndrome under Resight non-contact wide-angle lenses. This was a case-control study of 20 patients with Terson syndrome (study group) that underwent 25G vitrectomy under Resight non-contact wide-angle lenses, with those of 20 matched patients that underwent 20G vitrectomy (control group). Medical records were reviewed from between July 2011 and October 2013. Data included results of the Early Treatment Diabetic Retinopathy Study examination, ophthalmology B-scan ultrasonography and fundus photography. The mean age, follow-up time, the preoperative visual acuity of LogMAR and the preoperative intraocular pressure (IOP) were all comparable in the two groups (all P>0.05). There were statistically significant differences in postoperative visual acuity of LogMAR compared with preoperative visual acuity (P<0.001) in both groups, but no difference between the groups (P=0.845). However, the operative times (13.5 min in study group vs. 42 min in control group) and post-operative IOP at day 1 (13.5 vs. 20 mmHg) were significantly reduced in the study group compared to the control group (P<0.001). Therefore, the present findings suggest that 25G Vitrectomy for Terson syndrome under Resight non-contact wide-angle lenses can achieve a significantly shorter operative time and lower post-operative IOP compared with 20G Vitrectomy.
Su, Jing; Liu, Xinquan; Zheng, Lijun; Cui, Hongping
2015-06-20
we conducted our meta-analysis of published studies to assess existing evidence about the efficacy and safety of vitrectomy with ILM peeling vs. that of vitrectomy with no ILM peeling for Macular hole-induced retinal detachment. Databases, including Pubmed, Cochrane Library, Ovid, Web of Science, Wanfang and CNKI, were searched to identify studies comparing outcomes following vitrectomy with ILM peeling and that with no ILM peeling for macular hole-induced retinal detachment. The meta-analysis was performed by RevMan 5.1. Six comparative studies comprising 180 eyes were identified. It was indicated that the rate of retinal reattachment (Odds ratio (OR) = 3.03, 95 % Confidence interval (CI):1.35 to 6.78; P = 0.007) and macular hole closure (OR = 6.74, 95 % CI:3.26 to 13.93; P < 0.001) after initial surgery was higher and the rate of recurrent retinal detachment (OR = 0.08, 95 % CI:0.02 to 0.30; P = 0.0002) was lower in the group of vitrectomy with ILM peeling than that in the group of vitrectomy with no ILM peeling. However, the improved BCVA (Weighted mean difference (WMD) = 0.14, 95 % CI: -0.20 to 0.47; P = 0.42) and the rate of postoperative complications were similar between the two groups. Vitrectomy with internal limiting membrane peeling is an efficient and safe procedure for macular hole-induced retinal detachment.
Underwater Calibration of Dome Port Pressure Housings
NASA Astrophysics Data System (ADS)
Nocerino, E.; Menna, F.; Fassi, F.; Remondino, F.
2016-03-01
Underwater photogrammetry using consumer grade photographic equipment can be feasible for different applications, e.g. archaeology, biology, industrial inspections, etc. The use of a camera underwater can be very different from its terrestrial use due to the optical phenomena involved. The presence of the water and camera pressure housing in front of the camera act as additional optical elements. Spherical dome ports are difficult to manufacture and consequently expensive but at the same time they are the most useful for underwater photogrammetry as they keep the main geometric characteristics of the lens unchanged. Nevertheless, the manufacturing and alignment of dome port pressure housing components can be the source of unexpected changes of radial and decentring distortion, source of systematic errors that can influence the final 3D measurements. The paper provides a brief introduction of underwater optical phenomena involved in underwater photography, then presents the main differences between flat and dome ports to finally discuss the effect of manufacturing on 3D measurements in two case studies.
Novel Application of Helical Tomotherapy in Whole Skull Palliative Radiotherapy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rodrigues, George; Yartsev, Slav; Coad, Terry
2008-01-01
Helical tomotherapy (HT) is a radiation planning/delivery platform that combines inversely planned IMRT with on-board megavoltage imaging. A unique HT radiotherapy whole skull brain sparing technique is described in a patient with metastatic prostate cancer. An inverse HT plan and an accompanying back-up conventional lateral 6-MV parallel opposed pair (POP) plan with corresponding isodose distributions and dose-volume histograms (DVH) were created and assessed prior to initiation of therapy. Plans conforming to the planning treatment volume (PTV) with significant sparing of brain, optic nerve, and eye were created. Dose heterogeneity to the PTV target was slightly higher in the HT planmore » compared to the back-up POP plan. Conformal sparing of brain, optic nerve, and eye was achieved by the HT plan. Similar lens and brain stem/spinal cord doses were seen with both plans. Prospective clinical evaluation with relevant end points (quality of life, symptom relief) are required to confirm the potential benefits of highly conformal therapies applied to palliative situations such as this case.« less
de Nie, Karlijn F; Crama, N; Tilanus, Maurits A D; Klevering, B Jeroen; Boon, Camiel J F
2013-05-01
Primary vitreous floaters can be highly bothersome in some patients. In the case of persistently bothersome floaters, pars plana vitrectomy may be the most effective treatment. The aim of this study is to evaluate the incidence of complications, and patient satisfaction, after pars plana vitrectomy for disabling primary vitreous opacities. We included a total of 110 eyes that underwent pars plana vitrectomy between February 1998 and August 2010. Fifty-seven eyes (51.8%) underwent 20-gauge vitrectomy, whereas 53 eyes (48.2%) underwent 23-gauge vitrectomy. In a retrospective manner, we assessed intraoperative and postoperative complications. There was a considerable range of time between surgery and questionnaire (range: 4-136 months). Patient satisfaction was assessed by a questionnaire based on a modified NEI VFQ-25 questionnaire. A retinal detachment occurred in 10.9% of cases, and the incidence did not differ significantly between the 20-gauge and 23-gauge vitrectomy groups. In 4.5% of the eyes, a retinal detachment developed within the first 3 months, and 6.4% occurred later in the postoperative period. Cystoid macular edema occurred in 5.5%, and an epiretinal membrane was seen postoperatively in 3.6% of cases. Development of glaucoma requiring glaucoma surgery, a macular hole, and postoperative scotoma, each occurred in 0.9% of cases. No cases of endophthalmitis occurred. Eighty-five percent of patients were satisfied or very satisfied with the results of the vitrectomy. Eighty-four percent of all patients were completely cured from their troublesome vitreous floaters, and an additional 9.3% of patients were less troubled by vitreous floaters. Ten patients (9.3%) were dissatisfied, and six of these patients (5.6%) had a serious complication that resulted in permanent visual loss. Pars plana vitrectomy is an effective approach to treat primary vitreous floaters, resulting in a high rate of patient satisfaction. Postoperative complications may be more frequent than previously reported, so patients should be well-informed about the complication rate before reaching informed consent about this surgical intervention. Additional preventive measures should be considered to reduce this complication rate.
Geometric and Optic Characterization of a Hemispherical Dome Port for Underwater Photogrammetry
Menna, Fabio; Nocerino, Erica; Fassi, Francesco; Remondino, Fabio
2016-01-01
The popularity of automatic photogrammetric techniques has promoted many experiments in underwater scenarios leading to quite impressive visual results, even by non-experts. Despite these achievements, a deep understanding of camera and lens behaviors as well as optical phenomena involved in underwater operations is fundamental to better plan field campaigns and anticipate the achievable results. The paper presents a geometric investigation of a consumer grade underwater camera housing, manufactured by NiMAR and equipped with a 7′′ dome port. After a review of flat and dome ports, the work analyzes, using simulations and real experiments, the main optical phenomena involved when operating a camera underwater. Specific aspects which deal with photogrammetric acquisitions are considered with some tests in laboratory and in a swimming pool. Results and considerations are shown and commented. PMID:26729133
The treatment of malignant glaucoma in nanophthalmos: a case report.
Wang, Jie; Du, Ergang; Tang, Jinfei
2018-02-23
The management of eyes with nanophthalmos is a dilemma for ophthalmologists due to various complications, especial the eye with malignant glaucoma. We report a case of effective treatment for malignant glaucoma in nanophthalmos. An 82-year-old man was performed phacoemulsification in the right eye with normal ocular pressure and nanophthalmos. The surgery was uneventful: an intraocular lens (IOL) was placed and centered in the capsular bag. 2 months later, the patient presented with malignant glaucoma, and the intraocular pressure fluctuated between 18.6 mmHg and 30.8 mmHg with antiglaucoma medications. The patient did not respond to surgical peripheral iridotomy and goniosynechialysis. Then a single treatment with laser peripheral lens posterior capsulotomy and vitreous anterior membranectomy was performed. The intraocular pressure normalized, and the anterior chamber deepened within 24 h. The patient's condition remained stable for 9 months with no further treatment, and his Snellen corrected distance visual acuity was 20/50. The left eye of this patient was treated by combined surgery including phacoemulsification, IOL implantation, anterior vitrectomy, surgical peripheral iridotomy (PI), and goniosynechialysis. No intraoperative or postoperative complications were observed. This case suggests that it is essential to choose a suitable treatment for nanophthalmos patients to deal with malignant glaucoma and to reduce the incidence of malignant glaucoma.
Clarkson, Douglas McG; Manna, Avinish; Hero, Mark
2014-02-01
We describe the use of an analytical weighing balance of measurement accuracy 0.00001g for determination of concentrations of perfluropropane (C3F8) gas used in ophthalmic surgical vitrectomy procedures. A range of test eyes corresponding to an eye volume of 6.1ml were constructed using 27 gauge needle exit ducts and separately 20 gauge (straight) and 23 gauge (angled) entrance ports. This method allowed determination of concentration levels in the sample preparation syringe and also levels in test eyes. It was determined that a key factor influencing gas concentrations accuracy related to the method of gas fill and the value of dead space of the gas preparation/delivery system and with a significant contribution arising from the use of the particle filter. The weighing balance technique was identified as an appropriate technique for estimation of gas concentrations. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.
Pahlitzsch, T; Pahlitzsch, M-L; Sumarni, U; Pahlitzsch, M
2017-10-30
The aim of this study is to evaluate three refractive procedures: LenSx® (Alcon, Fort Worth, TX, USA) femto-laser in situ keratomileusis (LASIK), FEMTO LDV Z4® (Ziemer, Port, Switzerland) femto-LASIK, and photorefractive keratectomy (PRK) in terms of refractive outcome, perioperative complications, pain, and patient satisfaction. Data of 168 eyes (myopic n = 84) were included in this retrospective study. Of these, 54 eyes (n = 27, 33.85 ± 7.64 years) were treated with LenSx® femto-LASIK, 60 eyes (n = 30, 35.03 ± 7.46 years) with FEMTO LDV Z4® femto-LASIK, and 54 eyes (n = 27, 33.24 ± 8.52 years) with PRK. Photoablation was induced by a MEL80 Excimerlaser (Zeiss, Oberkochen, Germany). The corrected (V sc ) and uncorrected (V cc ) distance subjective visual acuity, corneal topography (Pentacam® HR; Wetzlar, Germany), and objective astigmatism (ARK-760A Refractometer ; Nidek, Fremont, CA, USA) were measured preoperatively, and 1 day, 1 week, 1 month, and 3 months postoperatively. Subjective pain (verbal rating scale) and patient satisfaction were also recorded. Subjective V sc showed significantly better results in both femto-LASIK cohorts compared to PRK (p < 0.05) 1 day and 1 week postoperatively. There was no significant difference between the groups in terms of spherical equivalent and astigmatism 3 months postoperatively. The LenSx® femto-LASIK caused flap complications. The highest patient satisfaction results were shown in the LDV Z4® group, followed by the LenSx® and PRK cohorts (p = 0.072). LDV Z4® femto-LASIK showed the lowest pain score 1 day postoperatively (p < 0.001). There was no significant correlation between target refraction and preoperative corneal thickness and astigmatism. Femtosecond laser-assisted LASIK is an effective procedure enabling rapid rehabilitation of visual acuity with low postoperative pain compared to PRK. There is no difference between the three techniques regarding refractive outcome after 3 months follow-up. LDV Z4® femto-LASIK can be recommended, if available, due to its low intraoperative complication rate and higher patient satisfaction compared to LenSx® femto-LASIK.
Dell'Omo, Roberto; Mura, Marco; Lesnik Oberstein, Sarit Y; Bijl, Heico; Tan, H Stevie
2012-04-01
To describe fundus autofluorescence and optical coherence tomography (OCT) features of the macula after pars plana vitrectomy for rhegmatogenous retinal detachment. Thirty-three eyes of 33 consecutive patients with repaired rhegmatogenous retinal detachment with or without the involvement of the macula were prospectively investigated with simultaneous fundus autofluorescence and OCT imaging using the Spectralis HRA+OCT (Heidelberg Engineering, Heidelberg, Germany) within a few weeks after the operation. Fundus autofluorescence imaging of the macula showed lines of increased and decreased autofluorescence in 19 cases (57.6%). On OCT, these lines corresponded to the following abnormalities: outer retinal folds, inner retinal folds, and skip reflectivity abnormalities of the photoreceptor inner segment/outer segment band. Other OCT findings, not related to abnormal lines on fundus autofluorescence, consisted of disruption of photoreceptor inner segment/outer segment band and collection of intraretinal or subretinal fluid. The presence of outer retinal folds significantly related to metamorphopsia but did not relate to poor postoperative visual acuity. Partial-thickness retinal folds occur commonly after vitrectomy for rhegmatogenous retinal detachment repair and may represent an important anatomical substrate for postoperative metamorphopsia. Fundus autofluorescence and OCT are both sensitive techniques for the detection of these abnormalities.
Macular Hole Development After Vitrectomy for Floaters: A Case Report.
Appeltans, Andrea; Mura, Marco; Bamonte, Giulio
2017-12-01
The purpose of this report is to describe a case of macular hole development after vitrectomy for floaters with induction of posterior vitreous detachment. A 44-year-old otherwise healthy man presented with visually debilitating floaters in his right eye; these had been present for more than 2 years. Preoperative examination was unremarkable in both eyes, apart from some degree of vitreous degeneration in the right eye. Preoperative visual acuity was 20/20 bilaterally. A 25-gauge transconjunctival sutureless pars plana complete vitrectomy with induction of posterior vitreous detachment was performed in the right eye. Upon examination 1 month after surgery, a small full-thickness macular hole was detected in the right eye. Visual acuity was diminished to 20/80. The macular hole was closed after a second vitrectomy with internal limiting membrane peeling and gas tamponade. Macular hole development should be listed as a possible complication of vitrectomy for visually debilitating floaters when a posterior vitreous detachment is induced during surgery.
NASA Astrophysics Data System (ADS)
Camattari, Riccardo
2017-09-01
Focusing a hard x-ray beam would represent an innovative technique for tumour treatment, since such a beam may deliver a dose to a tumour located at a given depth under the skin, sparing the surrounding healthy cells. A detailed study of a focusing system for hard x-ray aimed at radiotherapy is presented here. Such a focusing system, named Laue lens, exploits x-ray diffraction and consists of a series of crystals disposed as concentric rings capable of concentrating a flux of x-rays towards a focusing point. A feasibility study regarding the positioning tolerances of the crystalline optical elements has been carried out. It is shown that a Laue lens can effectively be used in the context of radiotherapy for tumour treatments provided that the mounting errors are below certain values, which are reachable in the modern micromechanics. An extended survey based on an analytical approach and on simulations is presented for precisely estimating all the contributions of each mounting error, analysing their effect on the focal spot of the Laue lens. Finally, a simulation for evaluating the released dose in a water phantom is shown.
Obata, Shumpei; Fujikawa, Masato; Iwasaki, Keisuke; Kakinoki, Masashi; Sawada, Osamu; Saishin, Yoshitsugu; Kawamura, Hajime; Ohji, Masahito
2017-01-01
To investigate anatomic changes in retinal thickness (RT) and functional changes after vitrectomy for idiopathic epiretinal membranes (ERMs) with and without internal limiting membrane (ILM) peeling. The medical records of 100 eyes of 96 patients with ERM who underwent vitrectomy and ERM removal were reviewed retrospectively. The RT was measured by optical coherence tomography, and the area was divided into 9 sections. The best-corrected visual acuity (BCVA), 9 RT areas, and incidence rates of recurrent ERM were compared between the groups with and without ILM peeling before the operation and 12 months postoperatively. Thirty-nine eyes that underwent vitrectomy with ILM peeling and 61 eyes that underwent vitrectomy without ILM peeling met the inclusion criteria. There were no significant differences between the groups in the BCVA and any of the RTs before the operation and 12 months postoperatively. The ERMs recurred in 8 (20.5%) of 39 eyes and 26 (42.6%) of 61 eyes in the groups with and without ILM peeling, respectively, with a difference that reached significance (p = 0.02) 12 months postoperatively. Vitrectomy for ERM affects the BCVA or the RTs 12 months postoperatively. Additional ILM peeling does not affect them, but it might reduce the ERM recurrence rate. © 2016 S. Karger AG, Basel.
Sato, Tomohito; Kinoshita, Rina; Taguchi, Manzo; Sugita, Sunao; Kaburaki, Toshikatsu; Sakurai, Yutaka; Takeuchi, Masaru
2018-01-01
Abstract Vitreous opacity (VO) is a common feature of intermediate uveitis, posterior uveitis, and panuveitis. Fundus observation is critical for determining the etiology of uveitis, however, is often interfered with VO. In these clinical settings, vitrectomy contributes to a correct diagnosis and guides alternative management strategies. The purpose of this study was to evaluate the diagnostic yield and surgical outcome of vitrectomy in uveitic patients with VO and compare the visual outcome between infectious and noninfectious uveitis. Forty-five eyes with uveitis-associated VO underwent diagnostic and therapeutic vitrectomy, and etiological diagnosis of uveitis was confirmed in 34 of 45 eyes (75.6%). The diagnoses were infectious uveitis in 13 eyes (28.9%), noninfectious uveitis in 21 eyes (46.7%), and unidentified uveitis in 11 eyes (24.4%). Visual acuity (VA) improvement rates at 6 months after surgery were 69.2%, 76.2%, and 90.9% in the infectious, noninfectious, and unidentified uveitis groups, with no significant difference among 3 groups. Significant decrease in inflammation score after vitrectomy was observed only in the infectious uveitis group. This study demonstrated that diagnostic vitrectomy for inflammatory eyes with VO of unknown etiology was effective in infectious and noninfectious uveitis, and the therapeutic effect of VA improvement was observed in both types of uveitis. PMID:29480837
Rahimy, E; Wilson, J; Tsao, T-C; Schwartz, S; Hubschman, J-P
2013-01-01
Purpose The aim of this study is to develop a novel robotic surgical platform, the IRISS (Intraocular Robotic Interventional and Surgical System), capable of performing both anterior and posterior segment intraocular surgery, and assess its performance in terms of range of motion, speed of motion, accuracy, and overall capacities. Patients and methods To test the feasibility of performing ‘bimanual' intraocular surgical tasks using the IRISS, we defined four steps out of typical anterior (phacoemulsification) and posterior (pars plana vitrectomy (PPV)) segment surgery. Selected phacoemulsification steps included construction of a continuous curvilinear capsulorhexis and cortex removal in infusion–aspiration (I/A) mode. Vitrectomy steps consisted of performing a core PPV, followed by aspiration of the posterior hyaloid with the vitreous cutter to induce a posterior vitreous detachment (PVD) assisted with triamcinolone, and simulation of the microcannulation of a temporal retinal vein. For each evaluation, the duration and the successful completion of the task with or without complications or involuntary events was assessed. Results Intraocular procedures were successfully performed on 16 porcine eyes. Four eyes underwent creation of a round, curvilinear anterior capsulorhexis without radialization. Four eyes had I/A of lens cortical material completed without posterior capsular tear. Four eyes completed 23-gauge PPV followed by successful PVD induction without any complications. Finally, simulation of microcannulation of a temporal retinal vein was successfully achieved in four eyes without any retinal tears/perforations noted. Conclusion Robotic-assisted intraocular surgery with the IRISS may be technically feasible in humans. Further studies are pending to improve this particular surgical platform. PMID:23722720
Tarkkanen, Ahti; Raivio, Virpi; Anttila, Veli-Jukka; Tommila, Petri; Ralli, Reijo; Merenmies, Lauri; Immonen, Ilkka
2004-04-01
To report a case of delayed fungal endophthalmitis by Paecilomyces variotii following uncomplicated cataract surgery. To our knowledge this is the first reported case of postoperative endophthalmitis by this species. We report the longterm clinical follow-up of an 83-year-old female who underwent uncomplicated sutureless, small-incision cataract surgery. She developed recurring uveitis 4 months after surgery. Vitreous tap and finally complete vitrectomy with removal of the capsular bag including the intraocular lens were performed. Fungi were studied by histopathology and culture. At histopathological examination, the fungi were found to be closely related with the capsular bag. A few mononuclear inflammatory cells were encountered. At culture, Paecilomyces variotii, a common ubiquitous non-pathogenic saprophyte, was identified. Despite systemic, intravitreal and topical antifungal therapy after vitrectomy the uveitis recurred several times, but no fungal organisms were isolated from the repeat intraocular specimen. At 18 months postoperatively the subject's visual acuity was finger counting at 2 metres. At the time of surgery the operating room air-conditioning system was undergoing repairs. Cases of fungal endophthalmitis after contamination from air-conditioning ventilation systems have been reported before, but none of the cases reported have been caused by P. variotii. P. variotii, a non-pathogenic environmental saprophyte, may be disastrous if introduced into the eye. International recommendations on the environmental control of the operating room air-conditioning ventilation system should be strictly followed. No intraoperative surgery should be undertaken while the air-conditioning system is undergoing repairs or service.
A case of perforating injury of eyeball and traumatic cataract caused by acupuncture
Shuang, Han; Yichun, Kong
2016-01-01
Perforating globe injury is the leading cause of monocular blindness and vision loss. A 58-year-old male was injured by acupuncture needle during acupuncture treatment for his cerebral infarction. To the best of our knowledge, this is the first case report of perforating injury of the eyeball and traumatic cataract caused by acupuncture. The patient was hospitalized due to diagnosis of perforating ocular injury, traumatic cataract, and corneal and iris perforating injury. Moreover, he had to accept treatments of phacoemulsification, anterior vitrectomy along with intraocular lens implantation in the sulcus to improve his visual acuity. As acupuncture therapy has been widely performed for various diseases and achieved highly approval, the aim of this report is to remind acupuncturists operating accurately to avoid unnecessary injury during the treatment process, or the cure can also become the weapon. PMID:27221689
Serratia marcescens endophthalmitis after pterygium surgery: a case report.
Yi, Myeong Yeon; Chung, Jin Kwon; Choi, Kyung Seek
2017-11-02
To report a case of Serratia marcescens endophthalmitis after pterygium surgery using the bare sclera technique with mitomycin C (MMC). A 69-year-old male patient underwent pterygium excision surgery using the bare sclera technique and 0.02% MMC. The patient presented with decreased visual acuity and pain from the day after the operation. Trans pars plana vitrectomy was performed and intravitreal antibiotics were administered. Cultures from the aqueous humor and intraocular lens were all positive for S. marcescens, which was sensitive to an empiric antibiotic regimen. The best corrected distant visual acuity, 1 month after treatment, was a finger count/50 cm, but the retinal layer structure and the vasculature were relatively well preserved. This is the first reported case of S. marcescens endophthalmitis after pterygium surgery. Endophthalmitis caused by S. marcescens has a devastating visual prognosis and may show a high clinical risk-benefit ratio for the application of MMC in pterygium surgery.
1983-11-16
vironments; and the other half will be from the training application, the sun’s interference with in- operational training environment. frared missiles... interference . Similarly, a The commercial simulators are adequately sup- lesser involvement in the design review process ported with far fewer spares and...Physical Design regulations on Electromagnetic Interference Manual (DM-13).(18) Electronic Se urity is provides some unclassified emanation data concerned
AGOR 28 SIO Shipyard Representative Bi-Weekly Progress Report
2015-11-06
or MMR bilge tops, if any. • Anchor Windlass – The test of Armstrong’s port side anchor windlass failed while the third shot was being paid out...Certificate of Sanitation for Armstrong because the sewage discharge is ahead of the water maker suction. • Ride Anti-Fouling Paint – The anti...with seventeen. Spares are always welcome.) • HVAC- Vendor is on board grooming the system. • Engine Room – Bilges and deck plates painted
NASA Astrophysics Data System (ADS)
Taddei, Phillip J.; Chell, Erik; Hansen, Steven; Gertner, Michael; Newhauser, Wayne D.
2010-12-01
Age-related macular degeneration (AMD), a leading cause of blindness in the United States, is a neovascular disease that may be controlled with radiation therapy. Early patient outcomes of external beam radiotherapy, however, have been mixed. Recently, a novel multimodality treatment was developed, comprising external beam radiotherapy and concomitant treatment with a vascular endothelial growth factor inhibitor. The radiotherapy arm is performed by stereotactic radiosurgery, delivering a 16 Gy dose in the macula (clinical target volume, CTV) using three external low-energy x-ray fields while adequately sparing normal tissues. The purpose of our study was to test the sensitivity of the delivery of the prescribed dose in the CTV using this technique and of the adequate sparing of normal tissues to all plausible variations in the position and gaze angle of the eye. Using Monte Carlo simulations of a 16 Gy treatment, we varied the gaze angle by ±5° in the polar and azimuthal directions, the linear displacement of the eye ±1 mm in all orthogonal directions, and observed the union of the three fields on the posterior wall of spheres concentric with the eye that had diameters between 20 and 28 mm. In all cases, the dose in the CTV fluctuated <6%, the maximum dose in the sclera was <20 Gy, the dose in the optic disc, optic nerve, lens and cornea were <0.7 Gy and the three-field junction was adequately preserved. The results of this study provide strong evidence that for plausible variations in the position of the eye during treatment, either by the setup error or intrafraction motion, the prescribed dose will be delivered to the CTV and the dose in structures at risk will be kept far below tolerance doses.
Long-Term Outcomes of Total Exudative Retinal Detachments in Stage 3B Coats Disease.
Li, Albert S; Capone, Antonio; Trese, Michael T; Sears, Jonathan E; Kychenthal, Andres; De la Huerta, Irina; Ferrone, Philip J
2018-06-01
To evaluate the long-term outcomes of treatment of total exudative retinal detachments (ERDs) secondary to Coats disease (stage 3B) and the role of vitrectomy. Retrospective, observational case series. A total of 16 eyes in 16 patients undergoing treatment for total ERDs secondary to Coats disease with at least 5 years of follow-up. We reviewed the records of patients with stage 3B Coats disease. The interventions, including the timing of vitrectomy if used, and clinical course were recorded. The primary outcome measures were visual acuity at the most recent appointment, whether there was progression to neovascular glaucoma (NVG) or phthisis bulbi, and need for enucleation. All patients received ablative treatment (photocoagulation or cryotherapy), with 8 having scleral buckling (SB) and 6 having external drainage of subretinal fluid (XD). Of the 12 patients who had pars plana vitrectomy (PPV), 8 had early PPV (EV) in the first year after presenting, and 4 of 8 in the expectant management group had late PPV (late vitrectomy) at a mean of 4.3 years post-presentation for treatment of significant traction retinal detachment (TRD). The other 4 patients of 8 in the expectant management group did not require vitrectomy. Mean follow-up overall was 9 1/2 years. At the date of last follow-up, 50% had no light perception or light perception vision, which was consistent across the subgroups that underwent EV (4/8), late vitrectomy (2/4), or no PPV (2/4). A total of 4 of 16 patients had progression to NVG or phthisis, 1 of whom required enucleation. In this retrospective series of patients with Stage 3B Coats disease, ablative therapy with a combination of PPV, XD, or SB was effective in preventing progression to NVG or phthisis in the majority of patients, thus preserving the globe. Half of the patients (4/8) in this series who did not undergo PPV in the early vitrectomy group developed late-onset TRD, suggesting a possible role for early prophylactic vitrectomy with possible SB and XD; however, this is balanced by the other half (4/8) in the expectant management group who did not require any vitrectomy. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Maier, M; Abraham, S; Frank, C; Lohmann, C P; Feucht, N
2017-02-01
To evaluate the resolution rate in patients with symptomatic vitreomacular traction (VMT) ≤ 1500 μm with or without macular holes ≤ 400 μm after therapy with intravitreal ocriplasmin (Jetrea®) injections in a clinical setting in comparison to transconjunctival vitrectomy. We examined 21 eyes of 21 consecutive patients with vitreomacular traction with or without macular holes who underwent intravitreal injection of 0.1 ml ocriplasmin and we retrospectively reviewed 18 eyes of 18 patients with VMT with or without FTMH who underwent 23-gauge vitrectomy. Vitreomacular traction resolved in 15 of 21 eyes treated with ocriplasmin after 6 month (71 %) compared to 100 % of eyes treated by vitrectomy. Of the 5 eyes that initially presented FTMH with VMT in the ocriplasmin group, 2 were closed 1 month after ocriplasmin treatment. The remaining 3 had vitrectomy and closed thereafter. Best corrected visual acuity was 0.38 ± 0.23 LogMAR at baseline, improving to 0.34 ± 0.24 LogMAR at 6 months after ocriplasmin treatment. Best corrected visual acuity in the vitrectomy group improved from 0.55 ± 0.29 LogMAR before operation to 0.53 ± 0.51 LogMAR 6 months postoperatively. Foveal thickness was 355.95 ± 114.53 μm at baseline, reducing to 277.77 ± 40.26 μm at 6 months after ocriplasmin treatment. Foveal thickness of eyes that underwent vitrectomy was 494.61 ± 126.02 μm at baseline, decreasing to 330.2 ± 88.85 μm 6 months postoperatively. When traction is ≤ 1500 μm, enzymatic vitreolysis with ocriplasmin is a therapeutic option. In the presence of VMT >1500 μm or ERM, surgical treatment with vitrectomy is associated with better outcomes. In small macular holes with VMT and in the absence of ERM, enzymatic vitreolysis with ocriplasmin is an option. In cases of holes >400 μm, or in the absence of evident VMT, or in the presence of ERM, vitrectomy is the first choice.
Early surgical managment of penetrating ocular injuries involving the posterior segment.
Michels, R G
1976-09-01
Pars plana vitrectomy technic can be used in the early management of certain penetrating ocular injuries involving the posterior segment, including selected intraocular foreign bodies. This study reports the results of ten consecutive cases of intraocular foreign bodies in the posterior segment treated by a combination of vitrectomy (including lensectomy when necessary) and foreign-body extraction with forceps. The foreign body was successfully removed in nine of ten eyes, and nine of ten eyes were salvaged. This favorable experience using early vitreous surgery suggests that the vitrectomy technic can be used in other penetrating injuries involving the posterior segment that are not associated with intraocular foreign bodies. Possible indications for early vitrectomy are presented, including cases with a poor prognosis when managed by conventional methods.
[Retinal whitening following vitrectomy for epiretinal macular membrane].
Uemura, A
1993-09-01
To investigate the clinical pictures of retinal whitening following epiretinal membrane dissection. I studied retrospectively the records of 18 eyes which had undergone vitrectomy. Two types of retinal whitening were observed: cotton wool-like spots within the superficial retinal layers and a linear or dendritic pattern within the deep retinal layers. The spots were mainly noted in idiopathic cases and resolved completely in a few weeks, and the pattern was observed in macular pucker cases after retinal detachment surgery and persisted for a long time after vitrectomy.
Chang, Wei-Cheng; Lin, Chin; Lee, Cho-Hao; Sung, Tzu-Ling; Tung, Tao-Hsin; Liu, Jorn-Hon
2017-01-01
Studies on vitrectomy with and without internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (ERM) have yielded uncertain results regarding clinical outcomes and recurrence rates. To compare the clinical outcomes of vitrectomy with and without ILM peeling for idiopathic ERM. Databases, including PubMed, Embase, Cochrane, Web of Science, Google Scholar, CNKI databases, FDA.gov, and ClinicalTrials.gov, published until July 2016, were searched to identify studies comparing the clinical outcomes following vitrectomy with ERM and ILM peeling and with only ERM peeling, for treating idiopathic ERM. Studies with sufficient data were selected. Pooled results were expressed as mean differences (MDs) and risk ratios (RRs) with corresponding 95% confidence intervals (CI) for vitrectomy with and without ILM peeling with regard to postoperative best corrected visual acuity (BCVA), central retinal thickness (CRT), and ERM recurrence rate. Eleven retrospective studies and one randomized controlled trial involving 756 eyes were identified. This demonstrated that the postoperative BCVA within 12 months was significantly better in the non-ILM peeling group (MD = 0.04, 95% CI: 0.00 to 0.08; P = 0.0460), but that the patients in the ILM peeling group had significantly better postoperative BCVA after 18 months (MD = -0.13, 95% CI: -0.23 to -0.04; P = 0.0049) than did those in the non-ILM peeling group. The non-ILM peeling group exhibited a higher reduction in postoperative CRT (MD = 51.55, 95% CI:-84.23 to -18.88; P = 0.0020) and a higher recurrence rate of ERM (RR = 0.34, 95% CI:0.16 to 0.72; P = 0.0048) than did the ILM peeling group. However, the improvement rates of BCVA (RR = 1.03, 95% CI:0.72 to 1.47; P = 0.8802) and postoperative CRTs (MD = 18.15, 95% CI:-2.29 to 38.60; P = 0.0818) were similar between the two groups. Vitrectomy with ILM peeling results in better visual improvement in long-term follow-ups and lower ERM recurrence rates, and vitrectomy with only ERM peeling is more efficacious in reduction of CRT than is vitrectomy with ILM peeling.
Kang, Hyunseung; Lee, Min Woo; Byeon, Suk Ho; Koh, Hyoung Jun; Lee, Sung Chul; Kim, Min
2017-09-01
Our purpose was to describe the clinical course, and individualized management approaches, of patients with migration of a dexamethasone implant into the anterior chamber. This was a retrospective review of four patients with seven episodes of anterior chamber migration of a dexamethasone implant. After 924 intravitreal dexamethasone injections, anterior migration of the implant occurred in four eyes of four patients (0.43%). All four eyes were pseudophakic: one eye had a posterior chamber intraocular lens in the capsular bag but in a post-laser posterior capsulotomy state, two eyes had a sulcus intraocular lens (IOL), and one eye had an iris-fixated retropupillary IOL. All eyes had a prior vitrectomy and no lens capsule. The time interval from injection to detection of the implant migration ranged from 2 to 6 weeks. Of the four eyes with corneal edema, only one eye required a corneal transplantation, although it was unclear whether the implant migration was the direct cause of the corneal decompensation because the patient had a history of bullous keratopathy resulting from an extended history of uveitis. All patients underwent surgical intervention: two patients with a repositioning procedure, and the other two patients with removal due to repeated episodes, although surgical removal was not always necessary to reverse the corneal complications. In our study, not all patients required surgical removal of the implants. Repositioning the implant back into the vitreous cavity may be considered as an option in cases involving the first episode with no significant corneal endothelial decompensation. Considering potential anterior segment complications and the loss of drug effectiveness together, an individualized approach is recommended to obtain the best treatment outcomes and to minimize the risk of corneal complications.
Grosso, Andrea; Charrier, Lorena; Lovato, Emanuela; Panico, Claudio; Mariotti, Cesare; Dapavo, Giancarlo; Chiuminatto, Roberto; Siliquini, Roberta; Gianino, Maria Michela
2014-04-01
Small-gauge vitreoretinal techniques have been shown to be safe and effective in the management of a wide spectrum of vitreoretinal diseases. However, the costs of the new technologies may represent a critical issue for national health systems. The aim of the study is to plan a Health Technology Assessment (HTA) by performing a comparative analysis between the 23- and 25-gauge techniques in the management of macular diseases (epiretinal membranes, macular holes, vitreo-macular traction syndrome). In this prospective study, 45-80-year-old patients undergoing vitrectomy surgery for macular disease were enrolled at the Torino Eye Hospital. In the HTA model we assessed the safety, clinical effectiveness, and cost and financial evaluation of 23-gauge compared with 25-gauge vitrectomies. Fifty patients entered the study; 14 patients underwent 23-gauge vitrectomy and 36 underwent 25-gauge vitrectomy. There was no statistically significant difference in post-operative visual acuity at 1 year between the two groups. No cases of retinal detachment or endophtalmitis were registered at 1-year follow-up. The 23-gauge technique was slightly more expensive than the 25-gauge: the total surgical costs were EUR1217.70 versus EUR1164.84 (p = 0.351). We provide a financial comparison between new vitreoretinal procedures recently introduced in the market and reimbursed by the Italian National Health System and we also stimulate a critical debate about the expensive technocratic model of medicine.
The rate of endophthalmitis after pars plana vitrectomy and its risk factors.
Tabatabaei, Seyed Ali; Soleimani, Mohammad; Vakili, Hadi; Naderan, Morteza; Lashay, Alireza; Faghihi, Houshang; Yaseri, Mehdi
2018-05-11
To study the incidence of endophthalmitis after pars plana vitrectomy, its causative organisms, and visual acuity outcomes. In this retrospective, comparative study, the medical records of patients with acute-onset postoperative endophthalmitis after pars plana vitrectomy at Farabi Eye Hospital, Tehran, Iran, during a 12-year period between January 2004 and November 2015 were reviewed. To compare the endophthalmitis patients with other cases who underwent pars plana vitrectomy at the same day and also the same operating room, a control group was developed by gathering the data from surgical records. In the present study, the incidence rate of pos- vitrectomy endophthalmitis was 0.04% (16/39783). The organisms identified in aqueous or vitreous cultures (culture positive 44%) included Streptococcus pneumoniae (two patients, 12.5%), Pseudomonas aeruginosa (two patients, 12.5%), fungi (two patients, 12.5%), and Streptococcus viridans (one patient, 6.25%). Visual acuity after treatment for endophthalmitis ranged from light perception (7 eyes) to hand motion (1 eye), and evisceration was performed in 8 eyes (50%). When comparing the cases (patients developing endophthalmitis) and controls (patients with no complications operated in the same day and place of operation with the case group), only not using tamponade showed a statistically significant relation with the occurrence of endophthalmitis (p = 0.034). Our results indicated low incidence of endophthalmitis after pars plana vitrectomy comparable to previous studies which resulted in poor visual acuity. It seems that not using tamponade might increase the risk of endophthalmitis among these patients.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moon, S; Kyung Hee University Hospital at Gangdong, Gangdong-gu; Kim, D
2015-06-15
Purpose: The hippocampus sparing during the cranial irradiation has become interesting because it may mitigate radiation-induced neurocognitive toxicity. Herein we report our preliminary study for sparing the hippocampus with and without tilling condition for patient with brain metastases. Methods: Ten patients previously treated with whole brain were reviewed. Five patients tilted the head to around 30 degrees and others were treated without tilting. Treatment plans of linear accelerator (Linac)-based volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) were generated for prescription dose of 30 Gy in 15 fractions. Hippocampal avoidance regions were created with 5-mm volumetric expansion aroundmore » the hippocampus. Whole brain, hippocampus and hippocampal avoidance volume were 1372cm3, 6cm3 and 30cm3 and hippocampal avoidance volume was 2.2% of the whole brain planned target volume in average. Organs at risk (OARs) are hippocampus, eyes, lens, and cochleae. Coverage index (CVI), conformity index (CI), homogeneity index (HI) and mean dose to OARs were used to compare dose characteristic of tilted and non-tilted cases. Results: In IMRT, when CI, CVI and HI of whole brain were 0.88, 0.09 and 0.98 in both tilted and non-tilted cases, absorbed dose of hippocampal avoidance volume in tilted cases were 10% lower than non-tilted cases. Doses in other OARs such as eyes, lens, and cochleae were also decreased about 20% when tilting the head. When CI, HI and CVI in VMAT were 0.9, 0.08 and 0.99, the dose-decreased ratio of OARs in both with and without tilting cases were almost the same with IMRT. But absolute dose of hippocampal avoidance volume in VMAT was 30% lower than IMRT. Conclusion: This study confirms that dose to hippocampus decreases if patients tilt the head. When treating the whole brain with head tilted, patients can acquire the same successful treatment Result and also preserve their valuable memory.« less
1984-09-01
Research Study Number Three. In 1982, Mr. Edward Brost , then a graduate student at AFIT, completed a thesis which further analyzed the effects of sole...task, Brost formulated three research questions. They are as follows: 1. Is there a reduction in replenishment spare parts prices when competition is...analysis, Brost made three significant conclusions. They are: 1. The introduction of competition into the replenishment spare parts acquisition process
ILM peeling in nontractional diabetic macular edema: review and metanalysis.
Rinaldi, M; dell'Omo, R; Morescalchi, F; Semeraro, F; Gambicorti, E; Cacciatore, F; Chiosi, F; Costagliola, C
2017-10-31
To evaluate the effect of internal limiting membrane (ILM) peeling during vitrectomy for nontractional diabetic macular edema. PUBMED, MEDLINE and CENTRAL were reviewed using the following terms (or combination of terms): diabetic macular edema, nontractional diabetic macular edema, internal limiting membrane peeling, vitrectomy, Müller cells. Randomized and nonrandomized studies were included. The eligible studies compared anatomical and functional outcomes of vitrectomy with or without ILM peeling for tractional and nontractional diabetic macular edema. Postoperative best-corrected visual acuity and central macular thickness were considered, respectively, the primary and secondary outcomes. Meta-analysis on mean differences between vitrectomy with and without ILM peeling was performed using inverse variance method in random effects. Four studies with 672 patients were eligible for analysis. No significant difference was found between postoperative best-corrected visual acuity or best-corrected visual acuity change of ILM peeling group compared with nonpeeling group. There was no significant difference in postoperative central macular thickness and central macular thickness reduction between the two groups. The visual acuity outcomes in patients affected by nontractional diabetic macular edema using pars plana vitrectomy with ILM peeling versus no ILM peeling were not significantly different. A larger prospective and randomized study would be necessary.
Ayyildiz, Onder; Hakan Durukan, Ali
2018-01-01
Objective This study was performed to compare the functional and anatomical results of endoscopic-assisted and temporary keratoprosthesis (TKP)-assisted vitrectomy in patients with combat ocular trauma (COT). Methods The medical records of 14 severely injured eyes of 12 patients who underwent endoscopy or TKP implantation in combination with vitreoretinal surgery from 2007 to 2015 were retrospectively evaluated. The patients' ocular history and functional and anatomic anterior and posterior segment results were analyzed. Results Eight eyes (57%) underwent TKP-assisted vitrectomy and six eyes (43%) underwent endoscopic vitrectomy. The most common cause of COT was detonation of improvised explosive devices (72%), and the most common type of injury was an intraocular foreign body (50%). The median time from trauma to surgery and the median surgical time were significantly shorter in the endoscopy than TKP group. The postoperative functional and anatomical results were not significantly different between the two groups. Conclusions TKP-assisted vitrectomy should be performed in eyes requiring extensive bimanual surgery. In such cases, a corneal graft must be preserved for the TKP at the end of the surgery. Endoscopy shortens the surgical time and can reduce the complication rate.
Clinical features and prognosis of eyeball rupture: eye injury vitrectomy study.
Feng, Kang; Wang, Chang-guan; Hu, Yun-tao; Yao, Yi; Jiang, Yan-rong; Shen, Li-jun; Pang, Xiu-qin; Nie, Hong-ping; Ma, Zhi-zhong
2015-01-01
The objective of the study was to delineate clinical characteristics, surgical interventions, anatomic and visual outcomes of ruptured eye balls after trauma, and establish the prognostic indicators, which can assist clinicians in making correct surgical decisions during globe exploration for ruptured eyes. The study design used was a multicentre prospective cohort study, including six university-affiliated tertiary hospitals. We selected 242 cases of ruptured globe from the Eye Injury Vitrectomy Study database, until 31 December 2012. All selected cases underwent vitreoretinal surgery, enucleation or evisceration, and were followed up for at least 6 months. Age, visual acuity (VA) after injury, ocular trauma zone, time to surgery, corneal laceration, scleral wound, extrusion of iris or lens, ciliary body damage, intraocular haemorrhage, retinal detachment or defect, proliferative vitreoretinopathy (PVR) and choroidal damage were the predisposing factors evaluated by logistic regression models. We compared the pre-surgical indicators between cases of anatomically restored eyes with VA of 4/200 or better, or eyes with initial no light perception restored light perception or better, and cases of VA worse than 4/200, silicone oil-sustained eyes, phthisis or enucleation. Nearly 40% of cases with ruptured globe were anatomically restored through vitreoretinal surgery. The closed-funnel retinal detachment or extensive retinal loss (odds ratio [OR] = 3.38, P = 0.026), PVR-C (OR = 3.45, P = 0.008), and choroidal damage (OR = 4.20, P = 0.004) were correlated with poor outcomes. The closed-funnel retinal detachment or extensive retinal loss, PVR-C, and choroidal damage are the risk factors for unfavourable outcomes in globe ruptures. © 2015 Royal Australian and New Zealand College of Ophthalmologists.
Hsu, Chia-Ming; Chen, Shih-Chou; Wu, Tsung-Tien; Sheu, Shwu-Jiuan
2017-08-01
To report our 3-year experience of 23-gauge transconjunctival sutureless vitrectomy (TSV) for acute postoperative endophthalmitis at a tertiary referral center in southern Taiwan. This retrospective chart review study included 19 patients with acute postoperative endophthalmitis who underwent 23-gauge TSV from January 2011 to January 2015 at Kaohsiung Veterans General Hospital, Taiwan. Bacterial and fungal cultures from aqueous samples, vitreous samples, or both were performed. Nineteen patients (12 male; 7 female) were included. The mean age was 72.4 ± 8.29 years. Acute postoperative endophthalmitis was noted in 18 patients after cataract surgery and in 1 patient after 23-gauge vitrectomy for a rhegmatogenous retinal detachment. Upon presentation, visual acuity was less than hand movement for 80% of the patients. Chief complaints included blurred vision (19 patients, 100%), followed by pain (10 patients, 52.6%) and red eye (4 patients, 21%). All patients were administered an intravitreal injection (IVI) of antibiotics and 23-gauge TSV, and the average number of IVIs was 2.68 ± 1.73 (1-9 IVIs). The interval between their initial eye symptoms and vitrectomy was 4.11 ± 4.73 days (0-2 days), and the interval between diagnosis with endophthalmitis and a vitrectomy was 1.11 ± 1.52 days (0-6 days). The final visual acuity was no light perception for 1 patient (5.3%), between 6/60 and 6/12 for 8 patients (42.1%), and 6/12 or better for 9 patients (47.4%). No retinal detachment or hypotony was noted postoperatively in any case. 23-gauge vitrectomy is safe and effective for the management of acute postoperative endophthalmitis. Early diagnosis and treatment with 23-gauge vitrectomy may provide a good visual outcome. Copyright © 2017. Published by Elsevier Taiwan LLC.
Reilly, Gayatri; Melamud, Alexander; Lipscomb, Peter; Toussaint, Brian
2015-09-01
To evaluate whether patients with macular pucker (epiretinal membrane [ERM]) and good preoperative visual acuity (20/50 or better) benefit from small-gauge pars plana vitrectomy with membrane peeling. Retrospective chart review of eyes undergoing small-gauge pars plana vitrectomy for ERM. Inclusion criterion was impaired visual acuity (20/50 or better) due to ERM. Exclusion criteria were preoperative visual acuity of 20/60 or worse, previous surgery (other than uncomplicated cataract surgery), and any documented evidence of macular or corneal disease that would limit visual potential. The main outcome measure was final visual acuity. Secondary outcomes included the role of internal limiting membrane peeling, and the effect of preoperative cystoid macular edema and internal limiting membrane peeling on visual acuity. One hundred and forty eyes met inclusion criteria of which 94% underwent 25-gauge vitrectomy (remainder had 23-gauge). There was a statistically significant improvement in final vision with the mean preoperative visual acuity of 0.305 logMAR (20/40) and 1-year visual acuity of 0.250 logMAR (20/35) (P = 0.0167). Cataract formation in phakic patients had a significant effect on the final visual outcome. Fifty-six of 63 patients (89%) in the phakic cohort developed a visually significant cataract by study end. The mean time to recommendation of cataract surgery was 8.4 months. Thirty-eight eyes (27%) had preoperative cystoid macular edema. Fifty-nine eyes (42%) underwent internal limiting membrane peeling. Neither one of these secondary outcome measures had a significant effect on the final visual outcome. Pars plana vitrectomy is both efficacious and safe an option for patients with ERMs and good preoperative vision. Eyes with an ERM and vision 20/50 or better had a statistically significant improvement in the final visual outcome after small-gauge pars plana vitrectomy surgery. As with large-gauge vitrectomy, cataract formation occurred in most phakic eyes within the first year after surgery.
Vitrectomy for full-thickness macular hole in adult-onset Coats’ disease
Kumar, Vinod; Kumar, Pradeep; Garg, Gaurav; Damodaran, Saurabh
2017-01-01
The occurrence of full thickness macular hole in Coats’ disease is extremely rare. The purpose of this case report is to report pars plana vitrectomy for the treatment of full thickness macular hole in a patient with adult onset Coats disease. A young male presented with decreased vision in his right eye because of full thickness macular hole. The macular hole was found to be associated with adult onset Coats’ disease that was evident on ultra-wide field imaging. The patient underwent laser photocoagulation to the vascular telangiectasia followed by pars plana vitrectomy, large internal limiting membrane peeling and gas tamponade. This resulted in regression of exudation, closure of macular hole and improvement in vision. Coats disease of adult onset can present with decreased vision because of full thickness macular hole. Vitrectomy with internal limiting membrane peeling can result in excellent visual outcome. PMID:29133668
No-patch 23-gauge vitrectomy under topical anesthesia: a pilot study.
Deka, Satyen; Bhattacharjee, Harsha; Barman, M J; Kalita, Kruto; Singh, Sunil Kumar
2011-01-01
A pilot study was designed to evaluate the safety and efficacy of 23-gauge vitrectomy under topical anesthesia. Five eyes of five patients underwent 23-gauge sutureless vitrectomy under topical anesthesia with a pledget soaked in 0.5% proparacaine hydrochloride anesthetic, for vitreous hemorrhage (four eyes), epiretinal membrane (one eye). Subjective pain and discomfort were graded using a visual analogue chart from 0 (no pain or discomfort) to 4 (severe pain and discomfort). At the end of surgery no patch was applied and patients were given dark glasses. Patients underwent an immediate postoperative assessment, followed by next day and one week postoperative evaluation. Four patients had Grade 0 pain during the surgery. One patient had Grade 1 pain during the placement and withdrawal of the micro cannulas. The surgical outcomes were favorable. 23-gauge vitrectomy under topical anesthesia is safe and effective in selected cases. Further study is recommended to validate the outcome of this study.
The timing of reconstruction in severe mechanical trauma.
Kuhn, Ferenc
2014-01-01
Serious ocular trauma involving the posterior segment remains rather common and, despite many technological advances in recent years, continues to represent a significant management challenge to the ophthalmologist. One of these challenges is to identify the most optimal timing for the ultimate reconstruction, namely vitrectomy. While it is fairly obvious that suture-closure of the wound of open-globe injuries should be done as soon as possible, it is less clear whether vitrectomy should be performed in the same surgical session (primary comprehensive reconstruction) or be deferred (staged approach), and if so for how long. In this review, 4 options for staging are offered: early (days 2-4); delayed (days 5-7); late (days 8-14), and very late (past 2 weeks). The earlier the vitrectomy, the higher the risk of intraoperative complications. Conversely, the later the vitrectomy, the higher the incidence and severity of postoperative complications, of which proliferative vitreoretinopathy is the most damaging.
Ocular consequences of bottle rocket injuries in children and adolescents.
Khan, Mehnaz; Reichstein, David; M Recchia, Franco
2011-05-01
To describe the spectrum of ocular injuries and associated visual morbidity in the pediatric and adolescent population caused by bottle rockets. Retrospective review of consecutive medical records of patients 18 years or younger seen during a recent 4-year period. Outcome measures were ocular injuries at time of visit, interventions required, visual acuity at most recent follow-up, and most recent anatomic findings. Eleven eyes from 10 patients (8 boys and 2 girls aged 5-17 years) were identified. Significant ocular injuries included corneal epithelial defect (7 eyes), hyphema (6 eyes), traumatic iritis (2 eyes), iridodialysis (4 eyes), cataract (4 eyes), retinal dialysis (1 eye), and vitreous hemorrhage (2 eyes). Eight eyes required primary intervention (lensectomy in 4 eyes, corneal debridement in 2 eyes, globe exploration in 1 eye, and retinal laser photocoagulation in 1 eye). Three patients required additional procedures. These secondary interventions included pars plana vitrectomy (1 eye), muscle surgery for sensory strabismus (1 eye), corneal debridement (1 eye), and intraocular lens placement (1 eye). Most recent visual acuity (10 eyes with follow-up) was 20/30 or better in 4 eyes and 20/200 or worse in 6 eyes (for 1 eye, the patient was unavailable for follow-up). Permanent visual impairment was typically due to traumatic maculopathy. Bottle rockets can cause significant ocular injury in children, often with permanent loss of vision.
Liu, Xin; Wang, Xiaoying; Lu, Yi; Zheng, Tianyu; Zhou, Xingtao
2016-01-01
Purpose. To analyze the safety, effectiveness, and stability of triplex surgery for phakic 6H anterior chamber phakic intraocular lens explantation and phacoemulsification with in-the-bag IOL implantation for super high myopia in long-term observations. Methods. This retrospective case series evaluated 16 eyes of 10 patients who underwent triplex surgery. Best corrected visual acuity (BCVA), endothelial cell density (ECD), and associated adverse events were evaluated. Results. The mean follow-up time after the triplex surgery was 46 ± 14 months. The mean logMAR BCVA was significantly improved after triplex surgery (P = 0.047). One eye developed endophthalmitis five days postoperatively and underwent pars plana vitrectomy (PPV). Five eyes with preoperative severe endothelial cell loss developed corneal decompensation and underwent keratoplasty at a mean time of 9.4 ± 2.6 months after the triplex surgery. One eye had graft failure and underwent a second keratoplasty. The eye developed rhegmatogenous retinal detachment and underwent PPV with silicone oil 18 months later. ECD before the triplex surgery was not significantly different compared with that at last follow-up (P = 0.495) apart from these five eyes. Three eyes (18.8%) developed posterior capsule opacification. Conclusions. Triplex surgery was safe and effective for phakic 6H related complicated cataracts. Early extraction before severe ECD loss is recommended. PMID:27190642
Adelman, Ron A; Parnes, Aaron J; Ducournau, Didier
2013-09-01
To study success and failure in the treatment of uncomplicated rhegmatogenous retinal detachments (RRDs). Nonrandomized, multicenter retrospective study. One hundred seventy-six surgeons from 48 countries spanning 5 continents provided information on the primary procedures for 7678 cases of RRDs including 4179 patients with uncomplicated RRDs. Reported data included specific clinical findings, the method of repair, and the outcome after intervention. Final failure of retinal detachment repair (level 1 failure rate), remaining silicone oil at the study's conclusion (level 2 failure rate), and need for additional procedures to repair the detachment (level 3 failure rate). Four thousand one hundred seventy-nine uncomplicated cases of RRD were included. Combining phakic, pseudophakic, and aphakic groups, those treated with scleral buckle alone (n = 1341) had a significantly lower final failure rate than those treated with vitrectomy, with or without a supplemental buckle (n = 2723; P = 0.04). In phakic patients, final failure rate was lower in the scleral buckle group compared with those who had vitrectomy, with or without a supplemental buckle (P = 0.028). In pseudophakic patients, the failure rate of the initial procedure was lower in the vitrectomy group compared with the scleral buckle group (P = 3×10(-8)). There was no statistically significant difference in failure rate between segmental (n = 721) and encircling (n = 351) buckles (P = 0.5). Those who underwent vitrectomy with a supplemental scleral buckle (n = 488) had an increased failure rate compared with those who underwent vitrectomy alone (n = 2235; P = 0.048). Pneumatic retinopexy was found to be comparable with scleral buckle when a retinal hole was present (P = 0.65), but not in cases with a flap tear (P = 0.034). In the treatment of uncomplicated phakic retinal detachments, repair using scleral buckle may be a good option. There was no significant difference between segmental versus 360-degree buckle. For pseudophakic uncomplicated retinal detachments, the surgeon should balance the risks and benefits of vitrectomy versus scleral buckle and keep in mind that the single-surgery reattachment rate may be higher with vitrectomy. However, if a vitrectomy is to be performed, these data suggest that a supplemental buckle is not helpful. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Lin, Chin; Lee, Cho-Hao; Sung, Tzu-Ling; Tung, Tao-Hsin
2017-01-01
Background Studies on vitrectomy with and without internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (ERM) have yielded uncertain results regarding clinical outcomes and recurrence rates. Objective To compare the clinical outcomes of vitrectomy with and without ILM peeling for idiopathic ERM. Methods Databases, including PubMed, Embase, Cochrane, Web of Science, Google Scholar, CNKI databases, FDA.gov, and ClinicalTrials.gov, published until July 2016, were searched to identify studies comparing the clinical outcomes following vitrectomy with ERM and ILM peeling and with only ERM peeling, for treating idiopathic ERM. Studies with sufficient data were selected. Pooled results were expressed as mean differences (MDs) and risk ratios (RRs) with corresponding 95% confidence intervals (CI) for vitrectomy with and without ILM peeling with regard to postoperative best corrected visual acuity (BCVA), central retinal thickness (CRT), and ERM recurrence rate. Results Eleven retrospective studies and one randomized controlled trial involving 756 eyes were identified. This demonstrated that the postoperative BCVA within 12 months was significantly better in the non-ILM peeling group (MD = 0.04, 95% CI: 0.00 to 0.08; P = 0.0460), but that the patients in the ILM peeling group had significantly better postoperative BCVA after 18 months (MD = −0.13, 95% CI: −0.23 to −0.04; P = 0.0049) than did those in the non-ILM peeling group. The non-ILM peeling group exhibited a higher reduction in postoperative CRT (MD = 51.55, 95% CI:−84.23 to −18.88; P = 0.0020) and a higher recurrence rate of ERM (RR = 0.34, 95% CI:0.16 to 0.72; P = 0.0048) than did the ILM peeling group. However, the improvement rates of BCVA (RR = 1.03, 95% CI:0.72 to 1.47; P = 0.8802) and postoperative CRTs (MD = 18.15, 95% CI:−2.29 to 38.60; P = 0.0818) were similar between the two groups. Conclusions Vitrectomy with ILM peeling results in better visual improvement in long-term follow-ups and lower ERM recurrence rates, and vitrectomy with only ERM peeling is more efficacious in reduction of CRT than is vitrectomy with ILM peeling. PMID:28622372
Surgery for post-vitrectomy cataract
Do, Diana V; Gichuhi, Stephen; Vedula, Satyanarayana S; Hawkins, Barbara S
2014-01-01
Background Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous which is used in the treatment of disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from cataract surgery. Objectives The objective of this review was to evaluate the effectiveness and safety of surgery for post-vitrectomy cataract with respect to visual acuity, quality of life, and other outcomes. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 4), Ovid MEDLINE, Ovid MEDLINE in-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily Update, Ovid OLDMED-LINE (January 1946 to May 2013), EMBASE (January 1980 to May 2013, Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to May 2013), PubMed (January 1946 to May 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 22 May 2013. Selection criteria We planned to include randomized and quasi-randomized controlled trials comparing cataract surgery with no surgery in adult patients who developed cataract following vitrectomy. Data collection and analysis Two authors screened the search results independently according to the standard methodological procedures expected by The Cochrane Collaboration. Main results We found no randomized or quasi-randomized controlled trials comparing cataract surgery with no cataract surgery for patients who developed cataracts following vitrectomy surgery. Authors' conclusions There is no evidence from randomized or quasi-randomized controlled trials on which to base clinical recommendations for surgery for post-vitrectomy cataract. There is a clear need for randomized controlled trials to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include gain of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, quality of life, and adverse events such as posterior capsular rupture. Both short-term (six-month) and long-term (one-year or two-year) outcomes should be examined. PMID:24357418
SUCCESSFUL CLOSURE OF FULL-THICKNESS MACULAR HOLES SECONDARY TO MACULAR VITELLIFORM LESIONS.
Galvin, Justin C; Chua, Brian E; Fung, Adrian T
2017-03-22
To describe the first reported cases of full-thickness macular holes secondary to vitelliform lesions that were successfully closed with vitrectomy surgery and gas tamponade. Two female patients developed visual loss secondary to bilateral vitelliform lesions and associated full-thickness macular holes. The patients underwent 25-gauge pars plana vitrectomy, internal limiting membrane peeling, and 26% sulfur hexafluoride gas, followed by 3 days of face-down positioning. In both patients, the macular holes remain closed 3 and 25 months postoperatively. Vitrectomy surgery with gas tamponade may successfully close full-thickness macular holes secondary to macular vitelliform lesions.
Development of medical treatment for eye injuries in the mainland of China over the past decade.
Wang, Chang-Guan; Ma, Zhi-Zhong
2016-12-01
In the article, the development of medical treatment for eye injuries in the mainland of China was reviewed. According to the data provided in Eye Injury Vitrectomy Study (EIVS), 27% of 72 eyes with no light perception (NLP) gained recovery in term of antomy and visual function. Vitrectomy initiated at more than 4 weeks after open eye injury is an independent risk factor for developing PVR. Prognosis of anatomy and visual function of the injured eye with PVR is markedly worse than that without PVR. Serious injuries of ciliary body, choroid and retina are three key parts of the eye with NLP. The concept that the treatment of the eye injury gradually focus on the whole globe is embodied. The data from 13575 in patients with traumatic eyes in 14 hospitals revealed that the rate of immediate enucleation was remarkable reduced with comparison of 20 years ago.
Blanco-Teijeiro, María José; Bande Rodriguez, Manuel; Mansilla Cuñarro, Raquel; Paniagua Fernández, Laura; Ruiz-Oliva Ruiz, Francisco; Piñeiro Ces, Antonio
2018-03-01
To determine the effectiveness of internal limiting membrane peeling during vitrectomy for macula-off primary rhegmatogenous retinal detachment in the prevention of postoperative epiretinal membrane formation and achievement of good visual outcomes and to identify preoperative and intraoperative risk factors for epiretinal membrane formation. We retrospectively analyzed data from 62 eyes of 62 consecutive patients with macula-off primary rhegmatogenous retinal detachment who underwent vitrectomy with (n = 30) or without (n = 32) internal limiting membrane peeling between January 2014 and March 2016 and were followed up for at least 12 months. The effects of internal limiting membrane peeling on visual outcomes and postoperative recovery of the macular structure were determined. We subsequently divided patients into an epiretinal membrane group and a non-epiretinal membrane group and assessed the effects of various preoperative and intraoperative factors on postoperative epiretinal membrane formation. Postoperative epiretinal membrane developed in 10 patients in the no internal limiting membrane peeling group and three patients in the internal limiting membrane peeling group. Postoperative visual acuity significantly improved in both groups. Epiretinal membrane formation was found to be correlated with a higher number of retinal breaks. Our results suggest that internal limiting membrane peeling during macula-off primary rhegmatogenous retinal detachment surgery can reduce the occurrence of postoperative epiretinal membrane, is safe, and results in favorable visual outcomes.
A Comparison of Single-, Two- and Three-Port Laparoscopic Myomectomy
Kim, Su Mi; Baek, Jong Min; Park, Eun Kyung; Jeung, In Cheul; Choi, Ji Hyang; Kim, Chan Joo
2015-01-01
Background and Objective: A recent FDA safety communication has discouraged the use of a power morcellator for myoma extraction and has called for a change in surgical techniques for myomectomy. The objective of this study was to compare surgical outcomes of laparoscopic single-, two-, and conventional three-port myomectomy and to evaluate the feasibility of contained manual morcellation for uterine myoma. Methods: This retrospective study was a review and analysis of data from 191 consecutive women who underwent single-, two-, or three-port myomectomy for the management of uterine myoma from January 1, 2009, through December 31, 2014. Results: The 3 study groups did not differ demographically. Apart from operative time, the single- and two-port groups showed operative outcomes comparable to those of the multiport group. The single-port group had significantly longer operative times (P = .0053) than the two- and three-port groups. However, in the latter half of the single-port cases, the operative time was similar to those in the three-port group. The two-port surgery group showed a consistent operative time without a learning period. Conclusion: Single- or two-port myomectomy with transumbilical myoma morcellation is feasible and safe, with outcomes comparable to those of three-port myomectomy. These results suggest the potential for minimally invasive management of symptomatic uterine myoma, without the use of a power morcellator. PMID:26648680
Variable path length spectrophotometric probe
O'Rourke, Patrick E.; McCarty, Jerry E.; Haggard, Ricky A.
1992-01-01
A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.
Ionizing radiation sensitivity of the ocular lens and its dose rate dependence.
Hamada, Nobuyuki
2017-10-01
In 2011, the International Commission on Radiological Protection reduced the threshold for the lens effects of low linear energy transfer (LET) radiation. On one hand, the revised threshold of 0.5 Gy is much lower than previously recommended thresholds, but mechanisms behind high radiosensitivity remain incompletely understood. On the other hand, such a threshold is independent of dose rate, in contrast to previously recommended separate thresholds each for single and fractionated/protracted exposures. Such a change was made predicated on epidemiological evidence suggesting that a threshold for fractionated/protracted exposures is not higher than an acute threshold, and that a chronic threshold is uncertain. Thus, the dose rate dependence is still unclear. This paper therefore reviews the current knowledge on the radiosensitivity of the lens and the dose rate dependence of radiation cataractogenesis, and discusses its mechanisms. Mounting biological evidence indicates that the lens cells are not necessarily radiosensitive to cell killing, and the high radiosensitivity of the lens thus appears to be attributable to other mechanisms (e.g., excessive proliferation, abnormal differentiation, a slow repair of DNA double-strand breaks, telomere, senescence, crystallin changes, non-targeted effects and inflammation). Both biological and epidemiological evidence generally supports the lack of dose rate effects. However, there is also biological evidence for the tissue sparing dose rate (or fractionation) effect of low-LET radiation and an enhancing inverse dose fractionation effect of high-LET radiation at a limited range of LET. Emerging epidemiological evidence in chronically exposed individuals implies the inverse dose rate effect. Further biological and epidemiological studies are warranted to gain deeper knowledge on the radiosensitivity of the lens and dose rate dependence of radiation cataractogenesis.
Rezende, Flavio A; Qian, Cynthia X; Sapieha, Przemyslaw
2014-05-01
To perform a microbiological contamination analysis of the vitreous during office-based micro-incision vitrectomy surgery (MIVS) assessing whether the bacteria detected correlated with patient's ocular conjunctival flora. This is a prospective, interventional, nonrandomized case series of patients undergoing office-based MIVS, anti-VEGF, and dexamethasone intravitreal injections (triple therapy) for the treatment of wet age-related macular degeneration (AMD) and diabetic macular edema (DME).All patients were operated at a small procedure room in an ambulatory clinic of the Department of Ophthalmology, University of Montreal, Quebec, Canada. Conjunctival samples were done before placing the sclerotomies. The MIVS was done with a 23-gauge retractable vitrector, a 27-gauge infusion line, and a 29-gauge chandelier. Undiluted and diluted vitreous were collected for aerobic, anaerobic and fungal cultures. Outcomes measured were bacterial species identification within samples collected from the conjunctiva and the vitreous. Thirty-seven patients (37 eyes) were recruited and completed over 17 months of follow-up. Twenty-eight had wet AMD and nine had DME. There were 13 men and 24 women, with a mean age of 78 years. Eighteen patients (46%) had culture positive conjunctival flora. Twenty-six bacterial colonies were tabulated in total from the conjunctival swabs. All bacteria detected were gram-positive bacteria (100%), most commonly: Staphylococcus epidermitis in 11 (42%) and Corynebacterium sp. in 6 (23%). Only 1/18 patients had more than 3 species isolated, 6/18 patients had 2 species and 11/18 patients had 1 species identified on the conjunctival swab. Only 1 of the 37 undiluted midvitreous samples was culture positive, equating to a contamination rate of 2.7%. None of the diluted vitreous samples were culture positive. All cultures were negative for fungus. No serious postoperative complications occurred, including bacterial endophthalmitis, choroidal detachment, and retinal detachment. This preliminary study of office-based MIVS gives us insights on the ocular surface microbial profile and vitreous contamination rate of performing such procedures outside the OR-controlled environment. Our initial results seem to indicate that there is little risk of bacterial translocation and contamination from the conjunctiva into the vitreous. Therefore, if endophthalmitis occurs post-operatively, the source may likely arise after the procedure. Larger studies are needed to confirm our data.
Chronic low-grade postoperative endophthalmitis in a child with Marfan syndrome
Khurram Butt, Darakhshanda; Scott, Robert A; Upendran, Muralidharan R
2017-01-01
This case report describes a 9-year-old male who presented to the emergency department with 2 days’ history of left painful red eye. On initial examination, his outside medical records indicated that he had bilateral subluxated lenses and had undergone left eye lensectomy with glued intrascleral fixation of an intraocular lens 8 weeks earlier. Vision in left eye was poor from first postoperative day but with no undue pain or redness, and poor vision was attributed to possible vitreous bleed. Subsequent postoperative course was uneventful. He was discharged from ophthalmic care on topical steroids and antibiotic drops, one week postsurgery. The eye was healing well until he developed pain, for which ophthalmic care was sought. He underwent anterior chamber tap with intravitreal injections. Aqueous samples were positive for Staphylococcus aureus DNA by polymerase chain reaction. Post vitrectomy and implant removal, his recovery was good and vision improved to 0.50 LogMar with aphakic correction. PMID:29180908
Németh, J; Molnár, F; Kocur, I
2002-01-01
To describe eye health-care services provided by in patient Departments of Ophthalmology in Hungary as of 1998. A standardised questionnaire was sent to all Hungarian in-patient ophthalmic departments. The response rate was 100%, and data from six university departments and 56 hospitals with ophthalmic units are summarised. During the 12-month period, a total of 78,008 ophthalmic operations were performed, by 489 ophthalmologists. They worked in 62 in-patient ophthalmic units having a total of 1952 beds. The cataract rate was 3564 operations per million inhabitants; intraocular lens implantation was performed on 97% of the cases. There were 591 corneal transplants, 1698 operations for retinal detachment and 510 vitrectomies for diabetic eye complications. The level of ophthalmic care in Hungary, judged on the basis of key objective parameters including number of ophthalmic specialists, number of ophthalmic beds, and the rates of surgery, generally conforms to standards prevailing in Western Europe, in spite of financial difficulties and the consequent lack of investment in new equipment and instruments, both major and minor.
Seuthe, A-M; Szurman, P; Boden, K T
2017-11-01
We report on a patient with postsurgical cystoid macular edema (CME) after phacoemulsification and multifocal intraocular lens (MIOL) implantation. At first, there was a very good reaction to intravitreal triamcinolone, inducing complete regression of the edema without increasing intraocular pressure (IOP). One year later the patient suffered from retinal detachment and was treated with vitrectomy, laser, and gas tamponade. Afterward, he developed macular pucker with edema. After surgical treatment with pucker peeling and intravitreal triamcinolone, the patient showed a steroid response and an increase IOP. Postoperatively, there was a recurrence of CME. A coincidental administration of a steroid injection intramuscularly by the general practitioner achieved a prompt reduction of the CME without increasing IOP. This case shows that an initially good reaction to triamcinolone without increasing IOP does not rule out a future steroid response, and that a potential treatment option for CME in patients with a known steroid response could consist of intramuscularly injected steroids.
Raman, Rajiv; Jain, Mukesh; Shah, Pratik K.; Sharma, Tarun; Gopal, Lingam; Bhende, Pramod S.; Srinivasan, Sangeetha; Jambulingam, Malathi
2018-01-01
Purpose To describe the incidence, risk factors, clinical presentation, causative organisms, and outcomes in patients with endophthalmitis following pars plana vitrectomy (20G and minimally invasive vitrectomy surgery (MIVS). Methods Of 111,876 vitrectomies (70,585 20-G 41,291 MIVS) performed, 45 cases developed acute-onset, postoperative endophthalmitis. Results The rate of culture positive and culture negative endophthalmitis was 0.021% (2.1/10,000 surgeries) and 0.019% (1.9/10,000 surgeries) overall, 0.031% (3.1/10,000 surgeries) and 0.025% (2.5/10,000 surgeries) in 20G, and 0.005% (0.5/10,000 surgeries) and 0.007% (0.7/10,000 surgeries) in the MIVS group respectively. Potential predisposing factors were as follows: diabetes, 46.7%; vitrectomy for vascular retinopathies, 44.4%; and vitrectomy combined with anterior segment surgeries, 35.5%. The culture proven rates were 53.3% overall, 55.0% for 20G and 40.0% for MIVS. The most common organism was Pseudomonas aeruginosa for 20G. Klebsiella and Staphylococcus aureus were isolated in the two culture positive cases in MIVS group. The follow-up period for the patients with endophthalmitis was 586.14 ± 825.15 days. Seven were lost to follow up beyond one week. Of the remaining 38, 13 (34.2%) cases had a favorable visual outcome (i.e., best-corrected visual acuity [BCVA] > 5/200) and 24 (63.2%) had unfavorable visual outcome (BCVA < 5/200). Group with culture test results negative had significantly better outcomes (P < 0.05) as compared to those with positive. Conclusions MIVS does not increase the risk of endophthalmitis. Outcomes are poor despite appropriate treatment, particularly in cases with culture results positive. PMID:29338030
Gurelik, Gokhan; Hasanreisoglu, Berati
2012-01-01
Purpose To compare the efficacy and safety of 23-gauge transconjunctival vitrectomy with the conventional 20-gauge method in idiopathic epiretinal membrane and macular hole surgery. Methods Sixty-one consecutive patients undergoing vitrectomy for idiopathic epiretinal membrane and macular hole were recruited to either 20- or 23-gauge vitrectomy groups and prospectively evaluated. Surgical success rates, operating time, surgery-related complications, long-term visual outcomes, and postoperative ocular surface problems are compared in the two groups. Results There were 31 eyes in the 20-gauge group and 33 eyes in the 23-gauge group. The macular hole closure rate after the first surgery was 83% and 90.9% in the 20-gauge and 23-gauge groups, respectively, with no significant difference between groups (p = 0.59). The success rate for idiopathic epiretinal membranes cases was 100% in both groups. There was no statistically significant difference between overall surgical times (p = 0.90). None of the patients in either group experienced postoperative complications of severe postoperative hypotony, vitreous hemorrhage or endophthalmitis, except one eye in the 20-gauge group, which was found to have retinal detachment. In both groups, statistically significant improvement in visual acuity was achieved 1-month postoperatively (p = 0.002) and thereafter at all postoperative visits (p < 0.05). The mean ocular surface scores were significantly lower in the 23-gauge group at all postoperative visits compared with the 20-gauge group scores (p = 0.001). Conclusions Transconjunctival 23-gauge vitrectomy appears to be as effective and safe as conventional 20-gauge vitrectomy in idiopathic epiretinal membrane and macular hole surgeries. PMID:23060720
Yuan, Jing; Zhang, Ling-Lin; Lu, Yu-Jie; Han, Meng-Yao; Yu, Ai-Hua; Cai, Xiao-Jun
2017-11-28
To evaluate the effects on vitrectomy with internal limiting membrane (ILM) peeling versus vitrectomy with inverted internal limiting membrane flap technique for macular hole-induced retinal detachment (MHRD). Pubmed, Cochrane Library, and Embase were systematically searched for studies that compared ILM peeling with inverted ILM flap technique for macular hole-induced retinal detachment. The primary outcomes are the rate of retinal reattachment and the rate of macular hole closure 6 months later after initial surgery, the secondary outcome is the postoperative best-corrected visual acuity (BCVA) 6 months later after initial surgery. Four studies that included 98 eyes were selected. All the included studies were retrospective comparative studies. The preoperative best-corrected visual acuity was equal between ILM peeling and inverted ILM flap technique groups. It was indicated that the rate of retinal reattachment (odds ratio (OR) = 0.14, 95% confidence interval (CI):0.03 to 0.69; P = 0.02) and macular hole closure (OR = 0.06, 95% CI:0.02 to 0.19; P < 0.00001) after initial surgery was higher in the group of vitrectomy with inverted ILM flap technique than that in the group of vitrectomy with ILM peeling. However, there was no statistically significant difference in postoperative best-corrected visual acuity (mean difference (MD) 0.18 logarithm of the minimum angle of resolution; 95% CI -0.06 to 0.43 ; P = 0.14) between the two surgery groups. Compared with ILM peeling, vitrectomy with inverted ILM flap technique resulted significantly higher of the rate of retinal reattachment and macular hole closure, but seemed does not improve postoperative best-corrected visual acuity.
No-patch 23-gauge vitrectomy under topical anesthesia: A pilot study
Deka, Satyen; Bhattacharjee, Harsha; Barman, M J; Kalita, Kruto; Singh, Sunil Kumar
2011-01-01
A pilot study was designed to evaluate the safety and efficacy of 23-gauge vitrectomy under topical anesthesia. Five eyes of five patients underwent 23-gauge sutureless vitrectomy under topical anesthesia with a pledget soaked in 0.5% proparacaine hydrochloride anesthetic, for vitreous hemorrhage (four eyes), epiretinal membrane (one eye). Subjective pain and discomfort were graded using a visual analogue chart from 0 (no pain or discomfort) to 4 (severe pain and discomfort). At the end of surgery no patch was applied and patients were given dark glasses. Patients underwent an immediate postoperative assessment, followed by next day and one week postoperative evaluation. Four patients had Grade 0 pain during the surgery. One patient had Grade 1 pain during the placement and withdrawal of the micro cannulas. The surgical outcomes were favorable. 23-gauge vitrectomy under topical anesthesia is safe and effective in selected cases. Further study is recommended to validate the outcome of this study. PMID:21350284
Microwave Power Combiner/Switch Utilizing a Faraday Rotator
NASA Technical Reports Server (NTRS)
Perez, Raul
2008-01-01
A proposed device for combining or switching electromagnetic beams would have three ports, would not contain any moving parts, and would be switchable among three operating states: Two of the ports would be for input; the remaining port would be for output. In one operating state, the signals at both input ports would be coupled through to the output port. In each of the other two operating states, the signal at only one input port would be coupled to the output port. The input port would be selected through choice of the operating state.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barten, Danique L. J., E-mail: d.barten@vumc.nl; Tol, Jim P.; Dahele, Max
Purpose: Proton radiotherapy for head-and-neck cancer (HNC) aims to improve organ-at-risk (OAR) sparing over photon radiotherapy. However, it may be less robust for setup and range uncertainties. The authors investigated OAR sparing and plan robustness for spot-scanning proton planning techniques and compared these with volumetric modulated arc therapy (VMAT) photon plans. Methods: Ten HNC patients were replanned using two arc VMAT (RapidArc) and spot-scanning proton techniques. OARs to be spared included the contra- and ipsilateral parotid and submandibular glands and individual swallowing muscles. Proton plans were made using Multifield Optimization (MFO, using three, five, and seven fields) and Single-field Optimizationmore » (SFO, using three fields). OAR sparing was evaluated using mean dose to composite salivary glands (Comp{sub Sal}) and composite swallowing muscles (Comp{sub Swal}). Plan robustness was determined for setup and range uncertainties (±3 mm for setup, ±3% HU) evaluating V95% and V107% for clinical target volumes. Results: Averaged over all patients Comp{sub Sal}/Comp{sub Swal} mean doses were lower for the three-field MFO plans (14.6/16.4 Gy) compared to the three-field SFO plans (20.0/23.7 Gy) and VMAT plans (23.0/25.3 Gy). Using more than three fields resulted in differences in OAR sparing of less than 1.5 Gy between plans. SFO plans were significantly more robust than MFO plans. VMAT plans were the most robust. Conclusions: MFO plans had improved OAR sparing but were less robust than SFO and VMAT plans, while SFO plans were more robust than MFO plans but resulted in less OAR sparing. Robustness of the MFO plans did not increase with more fields.« less
David Kasner, MD, and the Road to Pars Plana Vitrectomy
Blodi, Christopher F.
2016-01-01
David Kasner, MD (1927–2001), used his extensive dissections of eye bank eyes and experiences in teaching cataract surgery to resident physicians to realize that excision of vitreous when present in the anterior chamber of eyes undergoing cataract surgery was preferable to prior intraoperative procedures. Noting that eyes tolerated his maneuvers, he then performed planned subtotal open-sky vitrectomies; first on a traumatized eye in 1961, then on two eyes of patients with amyloidosis (1966–1967). The success of these operations was noted by others, most particularly Robert Machemer, MD. Kasner’s work directly led to further surgical developments, including closed pars plana vitrectomy. PMID:27660504
[Pars plana vitrectomy in treatment of ocular toxocariasis complications--case report].
Oficjalska-Młyńczak, J; Duda, A; Muzyka-Woźniak, M; Zajac-Pytrus, H; Marek, J
2001-01-01
Ocular toxocariasis in adults may cause serious diagnostic and therapeutic problems. We describe a case of a 54-year-old farmer who developed peripheral granuloma with dense connective tissue strands joined to the disc. The diagnosis was confirmed by high ELISA titers in the serum and vitreous body. We performed pars plana vitrectomy with epiretinal membrane removal and laser photocoagulation of the inferior retina, obtaining improvement of visual acuity. After a few weeks the patient returned with central retinal detachment and macular hole. After the second vitrectomy with use of silicon oil we obtained reattachment of the retina but without functional improvement.
Naseripour, Masood; Ghasempour, Adel; Falavarjani, Khalil Ghasemi; Sanjari, Mostafa Sultan; Yousefi, Maryam
2015-01-01
To report a case of perfluorocarbon liquid (PFCL) migration into the subarachnoid space at the time of vitreoretinal surgery in a patient with morning glory syndrome associated retinal detachment. A 9-year-old girl underwent pars plana vitrectomy and silicone oil injection for retinal detachment associated with morning glory syndrome. PFCL was used for retinal stabilization before endolaser photocoagulation. The retina detached, and repeated vitrectomy and silicone oil injection was performed. Postoperative magnetic resonance imaging revealed PFCL in the subarachnoid space. The migration of perfluorocarbon into the subarachnoid space is a rare complication of vitrectomy in patients with morning glory syndrome.
Hahn, Ursula; Krummenauer, Frank; Ludwig, Klaus
2018-06-01
Quantifying the subjective impairment due to floaters based on an indication-specific questionnaire and setting its change between prior to and 3/12 months after elective vitrectomy in relation to surgical risks. Single-arm longitudinal observational multicenter study. Sixty-four floater patients underwent 23G pars plana vitrectomy; simultaneous phacoemulsification was excluded. An overall self-rated impairment index (SRI) and sub-indices SRI were calculated on the basis of a modified Visual Quality of Life questionnaire (VQoL), which addresses general vision, glare, near-sight problems and mobility of floaters. SRI ranged from 0 to 100% (maximum impairment). Secondary endpoints included corrected visual acuity and complications. Data were collected prior to and 3 (n = 64) and 12 (n = 62) months after surgery. The median overall SRI improved (44, 12, 11%) with a statistically significant median reduction of 69% (95% confidence interval 50-89%) 3 months postop. The median sub-SRIs improved for glare (50, 17, 17%), near sight problems (50, 17, 8%), and mobility of floaters (43, 5, 0%). Sixteen eyes needed cataract surgery during follow-up (10 showed cataract already prior to vitrectomy). Eight complications were reported (6 intra-operative retinal holes, 2 post-operative retinal detachments). For the majority of floater patients, subjective impairment was profoundly reduced by vitrectomy. Benefits of surgery prevailed despite complications.
Abbey, Ashkan M; Van Laere, Lily; Shah, Ankoor R; Hassan, Tarek S
2017-05-01
To evaluate the preoperative features, intraoperative management, and postoperative outcomes of recurrent macular holes that developed after initial successful repair with small-gauge vitrectomy techniques. We retrospectively reviewed 392 eyes with idiopathic macular holes successfully treated with small-gauge vitrectomy. Thirteen of these eyes underwent reoperation after macular hole reopening. We assessed patient demographics, visual acuity, postoperative anatomical success, potential precipitating clinical factors of hole reopening, and details of the surgical repairs of these eyes. Macular hole reopening occurred in 13 (3.3%) of 392 eyes in a mean of 28 months (range, 1-120 months) after initial repair. All 13 recurrent holes closed after a second vitrectomy, but 4 (31%) holes reopened again and had vitrectomy. Of these, 2 reopened a third time. Ultimately, 11 (85%) holes were closed at the most recent follow-up. The mean best-corrected visual acuity was 20/81 before initial repair, 20/148 after the first reopening, 20/115 after repair of the first reopening, and 20/55 after repair of >1 reopening. Ten of 13 (77%) patients had, or later developed, macular holes in the other eye during follow-up. Reoperation successfully achieved hole closure and ultimate visual improvement in most eyes with recurrent macular holes. Most patients with recurrent holes previously had, or later developed, full-thickness macular holes in the other eye.
Akiyama, Kunihiko; Fujinami, Kaoru; Watanabe, Ken; Tsunoda, Kazushige; Noda, Toru
2016-11-01
To determine the efficacy of internal limiting membrane (ILM) peeling during vitrectomy for rhegmatogenous retinal detachment (RRD) regarding post-vitrectomy epiretinal membrane (ERM) development and visual outcomes. Retrospective, interventional, comparative case series. Setting: Institutional. One hundred and two consecutive eyes with RRD treated with vitrectomy and followed for at least 6 months. ILM was peeled without using dye such as indocyanine green (ICG). Observational Procedures: Patients were divided into 2 groups based on postoperative ERM development: Group 1, 81 eyes without ERM formation; Group 2, 21 eyes with ERM development. Patients also were divided into 2 subgroups: those with and without ILM peeling (58 and 44 eyes, respectively). Statistical analyses were performed between the 2 groups with/without ERM formation and between the 2 subgroups with/without ILM peeling for 5 preoperative factors including foveal involvement of the RRD, 4 intraoperative factors including ILM peeling, baseline best-corrected visual acuity (BCVA), and final BCVA. An association of ILM peeling with ERM prevention and the influence of ILM peeling on visual outcomes. ILM peeling was significantly (P < .001) associated with ERM prevention. There was no significant difference in the final BCVA between subgroups with and without ILM peeling. ILM peeling without ICG staining during the initial vitrectomy for RRDs may prevent postoperative ERM formation with favorable visual outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.
Nakajima, Takuya; Roggia, Murilo F; Noda, Yasuo; Ueta, Takashi
2015-09-01
To evaluate the effect of internal limiting membrane (ILM) peeling during vitrectomy for diabetic macular edema. MEDLINE, EMBASE, and CENTRAL were systematically reviewed. Eligible studies included randomized or nonrandomized studies that compared surgical outcomes of vitrectomy with or without ILM peeling for diabetic macular edema. The primary and secondary outcome measures were postoperative best-corrected visual acuity and central macular thickness. Meta-analysis on mean differences between vitrectomy with and without ILM peeling was performed using inverse variance method in random effects. Five studies (7 articles) with 741 patients were eligible for analysis. Superiority (95% confidence interval) in postoperative best-corrected visual acuity in ILM peeling group compared with nonpeeling group was 0.04 (-0.05 to 0.13) logMAR (equivalent to 2.0 ETDRS letters, P = 0.37), and superiority in best-corrected visual acuity change in ILM peeling group was 0.04 (-0.02 to 0.09) logMAR (equivalent to 2.0 ETDRS letters, P = 0.16). There was no significant difference in postoperative central macular thickness and central macular thickness reduction between the two groups. The visual acuity outcomes using pars plana vitrectomy with ILM peeling versus no ILM peeling were not significantly different. A larger randomized prospective study would be necessary to adequately address the effectiveness of ILM peeling on visual acuity outcomes.
Mauriello, Claudio; Chouillard, Elie; d'alessandro, Antonio; Marte, Gianpaolo; Papadimitriou, Argyri; Chahine, Elias; Kassir, Radwan
2018-04-16
Evaluate the efficacy of single-port sleeve gastrectomy (SPSG) and then compare it to a less-invasive sleeve approach (three-port) (3PSG) according to a propensity score (PS) matching analysis. We analyzed all patients who underwent SG through a three-port or a single-port laparoscopic approach. After 2 years, the follow-up was completed in 84% patients treated with 3PSG and 95% patients of the SPSG group. Excess weight loss (EWL) was comparable for the first year of follow-up within the two groups except for the controls at 3 months in which the SPSG group showed a higher EWL (p = 0.0243). We demonstrated the efficacy of SPSG in bariatric surgery even compared to another, less invasive, laparoscopic SG approach (three-port).
Kenney, Kristin S; Fanciullo, Lisa M
2005-07-01
Although air bags are placed in automobiles to act as safety devices, they have been shown to carry a risk of injury themselves. Ocular injury, in particular, can often be a direct consequence of air bag deployment. A case of ocular air bag injury is presented. A discussion and review of the current literature on this issue follows. A 63-year-old man was transferred to our clinic after sustaining injuries related to a motor vehicle accident, during which the automobile's air bag was deployed. Initial examination revealed many signs of blunt ocular trauma of the O.D., including iridodialysis, dislocated lens with traumatic cataract, and traumatic/inflammatory glaucoma. Initial B-scan showed an attached retina O.D. One month later, the patient underwent an attempted pars plana vitrectomy with lensectomy, iris repair, and insertion of an anterior chamber intraocular lens. Complications arose during the procedure, and a total retinal detachment developed. Resultant acuity is no light perception O.D. Although ocular morbidity can be a direct consequence of air bag deployment, most eye injuries are minimal, and seem to be outweighed by the benefits of air bags. Drivers, as well as passengers, can minimize associated injuries by adhering to specific safety guidelines. This, as well as continual modification and improvement in air bag design, will maximize the safety of air bags and decrease the incidence of vision-threatening ocular injury caused by air bag deployment.
Bang, Seung Pil; Jun, Jong Hwa
2017-04-04
A large iris defect or extensive iridodialysis can be an intractable cause of visual disturbance, photophobia, glare, monocular diplopia, or cosmetic deformity. The implantation of an artificial iris substitute could be an effective option, but this can cause a reduction in endothelial cell density. We succeeded in the anatomical restoration of iris tissue that was totally dialyzed out of the eye, and was preserved in cold balanced salt solution for 8 h. Engrafted iris tissue was maintained within the aqueous humor. A 71-year-old man was referred to our clinic for management of an iatrogenic total iridodialysis. The totally dialyzed iris tissue was immediately preserved in sterile cold balanced salt solution and packed in a sterile biopsy bottle that was surrounded with ice cubes. Under general anesthesia, a pars plana vitrectomy was performed to remove the remaining lens cortex and vitreous fiber anterior to the equator. A sulcus-positioned intraocular lens (IOL) was repositioned and fixed by ab externo scleral sutures. Preserved iris tissue was inserted and ironed using both iris spatula and ocular viscoelastic devices. Five-point ab interno scleral sutures were made 1.0 mm posterior to the limbus. The engrafted iris was successfully maintained for 6 months and did not undergo any atrophic change or depigmentation, which may be caused by primary implantation failure due to a blocked blood supply.
Intracorporeal hybrid single port vs conventional laparoscopic appendectomy in children.
Karam, Paul Anthony; Hiuser, Amy; Magnuson, David; Seifarth, Federico Gian Filippo
2016-12-20
Transumbilical laparoscopic assisted appendectomy combines laparoscopic single port dissection with open appendectomy after exteriorization of the appendix through the port site. Compared to the conventional three-port approach, this technique provides an alternative with excellent cosmetic outcome. We developed a safe and effective technique to perform an intracorporeal single port appendectomy, using the same laparoscope employed in the extracorporeal procedure. Retrospective review of 71 consecutively performed intracorporeal single port appendectomies and 30 conventional three-port appendectomies in children 6 to 17 years of age. A straight 10-mm Storz telescope with inbuilt 6 mm working channel is used to dissect the appendix, combined with one port-less 2.3 mm percutaneous grasper. Polymer WECK® hem-o-lock® clips are applied to seal the base of the appendix and the appendiceal vessels. No intraoperative complications were reported with the hybrid intracorporeal single port appendectomy or three-port appendectomy. There were two post-operative complications in the group treated with the single port hybrid technique: one intra-abdominal abscess and one surgical site infection. Groups did not differ in age, weight, and types of appendicitis. Operative times were shorter for the hybrid technique (70 vs 79 minutes) but did not differ significantly (P=0.19). This modified technique to a previously described single port extracorporeal appendectomy is easy to master and implement. It provides exposure similar to a three-port laparoscopic appendectomy, while maintaining virtually scarless results and potentially reduces the risk for surgical site infections compared to the extracorporeal technique.
Endophthalmitis following 27-Gauge Pars Plana Vitrectomy for Vitreous Floaters.
Lin, Zhong; Wu, Rong Han; Moonasar, Nived
2016-01-01
To report a case of Staphylococcus epidermidis endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. The clinical course and imaging findings, including fundus optomap, and spectral domain optical coherence tomography of a 24-year-old male patient were documented. The patient, with a preoperative best-corrected visual acuity (BCVA) of 1.0, developed endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. After a series of treatments, including emergent vitreous tap and silicone oil injection, antibiotic treatment, and silicone oil removal, the patient regained a BCVA of 0.6. Although rare, the potential risk of endophthalmitis should be explicitly discussed with patients considering surgical intervention for vitreous floaters.
Vitrectomy for epiretinal membrane in adult-onset Coats' disease.
Kumar, Pradeep; Kumar, Vinod
2017-10-01
Coats' disease is characterized by retinal vascular telangiectasia and subretinal and intraretinal exudation. A relatively benign form of the disease that occurs in adults is referred to as adult-onset Coats' disease. Involvement of macula in the form of macular edema and exudation are the common presenting features in both forms of the disease. We describe a rare case of adult-onset Coats' disease that presented with epiretinal membrane (ERM). Laser photocoagulation of retinal vascular telangiectasia resulted in worsening of patient's symptoms and ERM. Early pars plana vitrectomy resulted in resolution of the patient's symptoms. Utility of ultra-wide-field imaging and rationale of early vitrectomy in such cases are discussed.
Vitrectomy for epiretinal membrane in adult-onset Coats’ disease
Kumar, Pradeep; Kumar, Vinod
2017-01-01
Coats’ disease is characterized by retinal vascular telangiectasia and subretinal and intraretinal exudation. A relatively benign form of the disease that occurs in adults is referred to as adult-onset Coats’ disease. Involvement of macula in the form of macular edema and exudation are the common presenting features in both forms of the disease. We describe a rare case of adult-onset Coats’ disease that presented with epiretinal membrane (ERM). Laser photocoagulation of retinal vascular telangiectasia resulted in worsening of patient's symptoms and ERM. Early pars plana vitrectomy resulted in resolution of the patient's symptoms. Utility of ultra-wide-field imaging and rationale of early vitrectomy in such cases are discussed. PMID:29044085
Three-dimensional confocal microscopy of the living cornea and ocular lens
NASA Astrophysics Data System (ADS)
Masters, Barry R.
1991-07-01
The three-dimensional reconstruction of the optic zone of the cornea and the ocular crystalline lens has been accomplished using confocal microscopy and volume rendering computer techniques. A laser scanning confocal microscope was used in the reflected light mode to obtain the two-dimensional images from the cornea and the ocular lens of a freshly enucleated rabbit eye. The light source was an argon ion laser with a 488 nm wavelength. The microscope objective was a Leitz X25, NA 0.6 water immersion lens. The 400 micron thick cornea was optically sectioned into 133 three micron sections. The semi-transparent cornea and the in-situ ocular lens was visualized as high resolution, high contrast two-dimensional images. The structures observed in the cornea include: superficial epithelial cells and their nuclei, basal epithelial cells and their 'beaded' cell borders, basal lamina, nerve plexus, nerve fibers, nuclei of stromal keratocytes, and endothelial cells. The structures observed in the in- situ ocular lens include: lens capsule, lens epithelial cells, and individual lens fibers. The three-dimensional data sets of the cornea and the ocular lens were reconstructed in the computer using volume rendering techniques. Stereo pairs were also created of the two- dimensional ocular images for visualization. The stack of two-dimensional images was reconstructed into a three-dimensional object using volume rendering techniques. This demonstration of the three-dimensional visualization of the intact, enucleated eye provides an important step toward quantitative three-dimensional morphometry of the eye. The important aspects of three-dimensional reconstruction are discussed.
Gotzaridis, Stratos; Liazos, Efstathios; Petrou, Petros; Georgalas, Ilias
2017-01-01
A retrospective consecutive case series to evaluate the safety and efficacy of 25 gauge pars plana vitrectomy, ILM peeling, 20% SF 6 gas tamponade and strict posturing for the treatment of idiopathic full-thickness macular holes. We report the results of 106 consecutive eyes that underwent standard 25-gauge pars plana vitrectomy, brilliant peel-assisted internal limiting membrane peel, fluid:gas exchange with 20% SF 6 and strict posturing for one week. All patients were followed up at one week, one month, three months, and nine months postoperatively. Biomicroscopy at day 1 and biomicroscopy and OCT at week 1, months 1, 3, and 9 were used to assess macular hole status postoperatively. Pre- and postoperative logMAR visual acuity was compared. The macular hole was closed in 102/106 eyes postoperatively (96.2%). Four eyes showed unclosed macular holes and underwent additional SF 6 intravitreal injection and strict posturing for 10 days. All macular holes were eventually closed without the need of a second surgical procedure. Mean visual acuity improved from 0.63 logMAR preoperatively to 0.39 logMAR postoperatively. One case of retinal toxicity was reported due to accidental intravitreal injection of antibiotic. 25-gauge vitrectomy, ILM peel, and short-acting gas tamponade are highly effective for the treatment of macular holes. Additional intravitreal gas injection followed by strict posturing seems to be a simple and effective treatment for unclosed holes.
Midterm outcomes of single port thoracoscopic surgery for major pulmonary resection
2017-01-01
Introduction Single-port thoracoscopic surgery has widened the current minimally invasive surgical techniques toward more less invasive procedures in terms of reducing the number of incisions. However, the current status of oncologic outcome with this technique is not well known for lung cancer surgery. The purpose of this study is to evaluate the oncologic outcomes in early stage lung cancer for impact of the survival outcomes with our experience of conversion to a single-port approach from the conventional three-port approach. Materials and methods Retrospective data of patients who underwent thoracoscopic major lung resection for non-small cell lung cancer between January 2006 and June 2015 were analyzed. Patients’ characteristics, perioperative outcomes, pathologic result, and postoperative follow-up data of thoracoscopic surgery were reviewed and surgical outcomes were compared between conventional three-port (n = 168), two-port (n = 68), and single-port thoracoscopic surgery (n = 203). Results Of the 203 single-port thoracoscopic surgeries, we performed 167 single-port thoracoscopic lobectomy and mediastinal lymph node dissections. During the learning period of each thoracoscopic approach, the mean operation time for single-port thoracoscopic surgery (189±62 min) was not significantly different from those of two-port (175±46 min) and three-port (195±75 min) thoracoscopic lobectomy (p = 0.165). Perioperative outcomes including drain indwelling time (p <0.001), complication (p = 0.185) and conversion event (p = 0.911) were not worsened during learning period with two-port. Midterm survival (p = 0.753) and recurrence free survival (p = 0.656) of single port thoracoscopic lobectomy showed acceptable results compared with two- and three-port approach. Conclusions Single-port thoracoscopic surgery is safe and a feasible option for major lung resection in lung malignancy and this approach following experiences of two-port approach may yield similar oncologic results to those of conventional multi-port approach during thoracoscopic lobectomy. PMID:29136038
VITRECTOMY FOR MACULAR DISORDERS ASSOCIATED WITH LAMELLAR MACULAR HOLE EPIRETINAL PROLIFERATION.
Choi, Won Seok; Merlau, Daniel J; Chang, Stanley
2018-04-01
To compare the surgical outcome of a lamellar macular hole (LMH) depending on lamellar hole-associated epiretinal proliferation (LHEP) and full-thickness macular hole. This is a retrospective chart review. Thirty-three patients were enrolled for this study. The patients were divided into three groups depending on the type of macular hole and presence of LHEP. Group 1 had epiretinal membranes with LMH without LHEP, Group 2 had LMH with LHEP, and Group 3 had full-thickness macular hole with LHEP. The best-corrected visual acuity was recorded and optical coherence tomography scans were obtained. Preoperative best-corrected visual acuity showed no significant difference between groups (P = 0.968). Final visual acuity of Group 1 was better than that of Group 2 (P = 0.009). Group 1 showed less postoperative ellipsoid zone disruption compared with Group 2 (P = 0.010), and the duration of LHEP to surgery had no significant correlation with postoperative visual acuity (P = 0.629). Lamellar macular hole with LHEP showed poorer visual outcomes compared with those with highly reflective epiretinal membranes. Lamellar macular hole with LHEP showed a greater chance of ellipsoid zone disruption. These findings may explain the wide variability of visual outcomes previously reported after vitrectomy for LMH.
2007-10-30
S120-E-007426 (30 Oct. 2007) --- Astronaut Scott Parazynski, STS-120 mission specialist, participates in the third scheduled session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour, 8-minute spacewalk Parazynski and astronaut Doug Wheelock (out of frame), mission specialist, installed the P6 truss segment with its set of solar arrays to its permanent home, installed a spare main bus switching unit on a stowage platform, and performed a few get-ahead tasks. Also, Parazynski inspected the port Solar Alpha Rotary Joint (SARJ) to gather comparison data for the starboard rotary joint.
2007-10-30
S120-E-007424 (30 Oct. 2007) --- Astronaut Scott Parazynski, STS-120 mission specialist, participates in the third scheduled session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour, 8-minute spacewalk Parazynski and astronaut Doug Wheelock (out of frame), mission specialist, installed the P6 truss segment with its set of solar arrays to its permanent home, installed a spare main bus switching unit on a stowage platform, and performed a few get-ahead tasks. Also, Parazynski inspected the port Solar Alpha Rotary Joint (SARJ) to gather comparison data for the starboard rotary joint.
2007-10-30
ISS016-E-007423 (30 Oct. 2007) --- Astronaut Scott Parazynski, STS-120 mission specialist, participates in the third scheduled session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour, 8-minute spacewalk Parazynski and astronaut Doug Wheelock (out of frame), mission specialist, installed the P6 truss segment with its set of solar arrays to its permanent home, installed a spare main bus switching unit on a stowage platform, and performed a few get-ahead tasks. Also, Parazynski inspected the port Solar Alpha Rotary Joint (SARJ) to gather comparison data for the starboard rotary joint.
Intraocular biopsy using special forceps: a new instrument and refined surgical technique.
Akgul, Harun; Otterbach, Friedrich; Bornfeld, Norbert; Jurklies, Bernhard
2011-01-01
The aim was to investigate the Essen biopsy forceps as a new instrument and surgical approach for biopsy of intraocular tumours. Biopsy is indicated for assessment of any uncertain intraocular process or confirmation for presumed diagnosis before treatment. There is increasing interest for further genetic and immunocytological information in order to characterise the neoplasm, especially grading and prognosis of micrometastasis in uveal melanoma. The authors have developed a new surgical technique using special intraocular biopsy forceps. Twenty patients with uncertain intraocular subretinal tumour underwent biopsies carried out using the special Essen biopsy forceps. Biopsies were obtained through sutureless 23-gauge three-port vitrectomy. A small retinotomy tumour specimen was taken by the forceps branches. For further processing, the specimens were flushed out into a sterile tube and then sent to pathologists. The prebioptical tumour had a mean thickness of 3.48 mm (1.1 to 9.8 mm). In all cases (n=20) biopsies (0.3-2.1 mm in size) were obtained, in 19 cases (95%) allowing precise histological and immunohistochemical typing of the lesions following cytoblock embedding. Uveal melanoma was diagnosed in 50% (n=10), choroidal metastasis in 15% (n=3) and choroidal naevus in 15% (n=3); other diagnoses (n=3) included choroidal haemangioma, B cell lymphoma and old subretinal haemorrhage. Apart from three patients with temporary punctual bleeding on the surface, there were no intra- and postoperative complications. Biopsy using special forceps is a promising new approach and precise surgical procedure. Especially for small intraocular tumours, this technique has the advantage in providing enough tissue for improved histological examination and presenting a low risk for complications.
Moreira Neto, Carlos Augusto; Moreira Junior, Carlos Augusto
2013-01-01
To evaluate 5 patients with serous macular detachment due to optic disc pit that were submitted to pars plana vitrectomy and were followed for at least 7 years. Patients were submitted to pars plana vitrectomy, posterior hyaloid removal, autologous serum injection and gas-fluid exchange, without laser photocoagulation, and were evaluated pre and post-operatively with visual acuity and Amsler grid testing, retinography, and recently, with autofluorescence imaging and high resolution OCT. All 5 eyes improved visual acuity significantly following the surgical procedure maintaining good vision throughout the follow-up period. Mean pre-operative visual acuity was 20/400 and final visual acuity was 20/27 with a mean follow-up time of 13.6 years. No recurrences of serous detachments were observed. OCT examinations demonstrated an attached retina up to the margin of the pit. Serous macular detachments due to optic disc pits were adequately treated with pars plana vitrectomy and gas fluid exchange, without the need for laser photocoagulation, maintaining excellent visual results for a long period of time.
Darsová, Denisa; Pochop, Pavel; Štěpánková, Jana; Dotřelová, Dagmar
2018-01-01
To evaluate the efficacy of pars plana vitrectomy (PPV) as an anti-inflammatory therapy in pediatric recurrent intermediate uveitis. A retrospective study evaluated the long-term results of PPV indicated for intermediate uveitis with a mean observation period of 10.3 years (range 7-15.6 years) in 6 children (mean age 8 years, range 6-12 years). Pars plana vitrectomy was performed on 10 eyes in the standard manner and was initiated by vitreous sampling for laboratory examination. Data recorded were perioperative or postoperative vitrectomy complications, anatomic and functional results of PPV, and preoperative and postoperative best-corrected Snellen visual acuity. No perioperative or postoperative complications were observed. Bacteriologic, virologic, mycotic, and cytologic analysis of the vitreous was negative in all tested children. Five eyes were subsequently operated on for posterior subcapsular cataracts. An average preoperative visual acuity of 0.32 improved to an average postoperative visual acuity of 0.8. In the case of systemic immunosuppressive treatment failure in pediatric uveitis, particularly in eyes with cystoid macular edema, we recommend PPV relatively early.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ward, Matthew Christopher, E-mail: wardm3@ccf.org; Pham, Yvonne D.; Kotecha, Rupesh
2016-04-01
Conventional parallel-opposed radiotherapy (PORT) is the established standard technique for early-stage glottic carcinoma. However, case reports have reported the utility of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) with or without image guidance (image-guided radiotherapy, IGRT) in select patients. The proposed advantages of IMRT/VMAT include sparing of the carotid artery, thyroid gland, and the remaining functional larynx, although these benefits remain unclear. The following case study presents a patient with multiple vascular comorbidities treated with VMAT for early-stage glottic carcinoma. A detailed explanation of the corresponding treatment details, dose-volume histogram (DVH) analysis, and a review of the relevant literaturemore » are provided. Conventional PORT remains the standard of care for early-stage glottic carcinoma. IMRT or VMAT may be beneficial for select patients, although great care is necessary to avoid a geographical miss. Clinical data supporting the benefit of CRT are lacking. Therefore, these techniques should be used with caution and only in selected patients.« less
A reconfigurable common spare for co-located direct television broadcasting satellites
NASA Astrophysics Data System (ADS)
Roederer, A.; Fromm, H.-H.; Berretta, G.
1984-10-01
Spare spacecraft are needed to assure continuous operation in broadcasting services provided with the aid of satellites. The present investigation is concerned with the employment of a common spare approach in which two or three countries share one or several spare spacecraft that can support or temporarily replace any of the prime satellites. Such common spares would have to be reconfigurable to adapt their antenna coverage and polarization, as well as their operating frequencies and possibly their RF output power, to the corresponding parameters assigned to the country to be served. The considered concept is discussed, taking into account questions related to system and transponder, a repointable antenna with a few feed horns, a fixed antenna (apart from fine pointing) with more feeds, and a reconfigurable broadcast payload for a common spare. A common spare for France, Germany, and Italy is considered along with a common spare for the United Kingdom and Spain.
Safety of vitrectomy for floaters.
Tan, H Stevie; Mura, Marco; Lesnik Oberstein, Sarit Y; Bijl, Heico M
2011-06-01
To assess the risks of vitrectomy for the removal of primary and secondary vitreous opacities. Retrospective, nonrandomized, interventional case series. We reviewed the results of 116 consecutive cases of vitrectomy for vitreous floaters. Eighty-six cases were primary and 30 cases were secondary floaters. Main outcome measures were the incidence of iatrogenic retinal breaks and postoperative rhegmatogenous retinal detachments. We found iatrogenic retinal breaks in 16.4% of operations. There was no statistically significant difference in risk between cases of primary and secondary floaters. Intraoperative posterior vitreous detachment induction was found to increase significantly the risk of breaks. Retinal detachment occurred in 3 cases (2.5%), all after operations for primary floaters. One case of complicated retinal detachment ended with a low visual acuity of hand movements. Cataract occurred in 50% of phakic cases. Transient postoperative hypotony was found after 5.2% of our operations, and transient postoperative high intraocular pressure was encountered in 7.8%. An intraoperative choroidal hemorrhage occurred in 1 case, which resolved spontaneously. The mean visual acuity improved from 0.20 to 0.13 logarithm of the minimal angle of resolution units. The risk profile of vitrectomy for floaters is comparable with that of vitrectomy for other elective indications. Retinal breaks are a common finding during surgery and treatment of these breaks is crucial for the prevention of postoperative retinal detachment. Patients considering surgery for floaters should be informed specifically about the risks involved. Copyright © 2011 Elsevier Inc. All rights reserved.
Technical and instrumental prerequisites for single-port laparoscopic solo surgery: state of art.
Kim, Say-June; Lee, Sang Chul
2015-04-21
With the aid of advanced surgical techniques and instruments, single-port laparoscopic surgery (SPLS) can be accomplished with just two surgical members: an operator and a camera assistant. Under these circumstances, the reasonable replacement of a human camera assistant by a mechanical camera holder has resulted in a new surgical procedure termed single-port solo surgery (SPSS). In SPSS, the fixation and coordinated movement of a camera held by mechanical devices provides fixed and stable operative images that are under the control of the operator. Therefore, SPSS primarily benefits from the provision of the operator's eye-to-hand coordination. Because SPSS is an intuitive modification of SPLS, the indications for SPSS are the same as those for SPLS. Though SPSS necessitates more actions than the surgery with a human assistant, these difficulties seem to be easily overcome by the greater provision of static operative images and the need for less lens cleaning and repositioning of the camera. When the operation is expected to be difficult and demanding, the SPSS process could be assisted by the addition of another instrument holder besides the camera holder.
Optical aberrations in underwater photogrammetry with flat and hemispherical dome ports
NASA Astrophysics Data System (ADS)
Menna, Fabio; Nocerino, Erica; Remondino, Fabio
2017-06-01
The paper analyses differences between dome and flat port housings used for underwater photogrammetry. The underwater environment negatively affects image quality and 3D reconstructions, but this influence on photogrammetric measurements, so far, has not been addressed properly in the literature. In this work, motivations behind the need for systematic underwater calibrations are provided, then experimental tests using a specifically designed photogrammetric modular test object in laboratory and at sea are reported. The experiments are carried out using a Nikon D750 24 Mpx DSLR camera with a 24 mm f2.8 AF/D lens coupled with a NIMAR NI3D750ZM housing, equipped first with a dome and, successively, with a flat port. To quantify the degradation of image quality, MTF measurements are carried out, then the outcomes of self-calibrating bundle adjustment calibrations are shown and commented. Optical phenomena like field curvature as well as chromatic aberration and astigmatism are analysed and their implications on the degradation of image quality is factored in the bundle adjustment through a different weighting of 2D image observations.
Vitrectomy for floaters: prospective efficacy analyses and retrospective safety profile.
Sebag, Jerry; Yee, Kenneth M P; Wa, Christianne A; Huang, Laura C; Sadun, Alfredo A
2014-06-01
Floaters impact vision but the mechanism is unknown. We hypothesize that floaters reduce contrast sensitivity function, which can be normalized by vitrectomy, and that minimally invasive vitrectomy will have lower incidences of retinal tears (reported at 30%) and cataracts (50-76%). Seventy-six eyes (34 phakic) with floaters were evaluated in 2 separate studies. Floater etiologies were primarily posterior vitreous detachment in 61 of 76 eyes (80%) and myopic vitreopathy in 24 of 76 eyes (32%). Minimally invasive 25G vitrectomy was performed without posterior vitreous detachment induction, leaving anterior vitreous, and using nonhollow probes for cannula extraction. Efficacy was studied prospectively (up to 9 months) in 16 floater cases with Freiburg Acuity Contrast Testing (Weber index [%W] reproducibility = 92.1%) and the National Eye Institute Visual Function Questionnaire. Safety was separately evaluated in 60 other cases followed up on an average of 17.5 months (range, 3-51 months). Floater eyes had 67% contrast sensitivity function attenuation (4.0 ± 2.3 %W; control subjects = 2.4 ± 0.9 %W, P < 0.013). After vitrectomy, contrast sensitivity function normalized in each case at 1 week (2.0 ± 1.4 %W, P < 0.01) and remained normal at 1 month (2.0 ± 1.0 %W, P < 0.003) and 3 months to 9 months (2.2 ± 1.5 %W, P < 0.018). Visual Function Questionnaire was 28.3% lower in floater patients (73.2 ± 15.6, N = 16) than in age-matched control subjects (93.9 ± 8.0, N = 12, P < 0.001), and postoperatively improved by 29.2% (P < 0.001). In the safety study of 60 floater cases treated with vitrectomy, none developed retinal breaks, infection, or glaucoma after a mean follow-up of 17.5 months. Only 8 of 34 cases (23.5%) required cataract surgery (none younger than 53 years) at an average of 15 months postvitrectomy. Floaters lower contrast sensitivity function, which normalizes after vitrectomy. Visual Function Questionnaire quantified improvement in satisfaction. Not inducing posterior vitreous detachment reduced retinal tear incidence from 30% to 0% (P < 0.007). Postvitrectomy cataract incidence was reduced from 50% to 23.5% (P < 0.02). This approach thus seems effective and safe in alleviating the visual dysfunction induced by floaters.
Shinya, Akihiko; Mitsugi, Satoshi; Kuramochi, Eiichi; Notomi, Masaya
2005-05-30
We have devised an ultra-small multi-channel drop filter based on a two-port resonant tunneling system in a two-dimensional photonic crystal with a triangular air-hole lattice. This filter does not require careful consideration of the interference process to achieve a high dropping efficiency. First we develop three-port systems based on a two-port resonant tunneling filter. Next we devise a multi-port channel drop filter by cascading these three-port systems. In this paper, we demonstrate a ten-channel drop filter with an 18 mum device size by 2D-FDTD calculation, and a three-port resonant tunneling filter with 65+/- 20 % dropping efficiency by experiment.
INTERNAL LIMITING MEMBRANE PEELING IN MACULAR HOLE SURGERY; WHY, WHEN, AND HOW?
Chatziralli, Irini P; Theodossiadis, Panagiotis G; Steel, David H W
2018-05-01
To review the current rationale for internal limiting membrane (ILM) peeling in macular hole (MH) surgery and to discuss the evidence base behind why, when, and how surgeons peel the ILM. Review of the current literature. Pars plana vitrectomy is an effective treatment for idiopathic MH, and peeling of the ILM has been shown to improve closure rates and to prevent postoperative reopening. However, some authors argue against ILM peeling because it results in a number of changes in retinal structure and function and may not be necessary in all cases. Furthermore, the extent of ILM peeling optimally performed and the most favorable techniques to remove the ILM are uncertain. Several technique variations including ILM flaps, ILM scraping, and foveal sparing ILM peeling have been described as alternatives to conventional peeling in specific clinical scenarios. Internal limiting membrane peeling improves MH closure rates but can have several consequences on retinal structure and function. Adjuvants to aid peeling, instrumentation, technique, and experience may all alter the outcome. Hole size and other variables are important in assessing the requirement for peeling and potentially its extent. A variety of evolving alternatives to conventional peeling may improve outcomes and need further study.
Surgical management of anterior chamber epithelial cysts.
Haller, Julia A; Stark, Walter J; Azab, Amr; Thomsen, Robert W; Gottsch, John D
2003-03-01
To review management strategies for treatment of anterior chamber epithelial cysts. Retrospective review of consecutive interventional case series. Charts of patients treated for epithelial ingrowth over a 10-year period by a single surgeon were reviewed. Cases of anterior chamber epithelial cysts were identified and recorded, including details of ocular history, preoperative and postoperative acuity, intraocular pressure (IOP), and ocular examination, type of surgical intervention, and details of further procedures performed. Seven eyes with epithelial cysts were identified. Patient age ranged from 1.5 to 53 years at presentation. Four patients were children. In four eyes, cysts were secondary to trauma, one case was presumably congenital, one case developed after corneal perforation in an eye with Terrien's marginal degeneration, and one case developed after penetrating keratoplasty (PK). Three eyes were treated with vitrectomy, en bloc resection of the cyst and associated tissue, fluid-air exchange and cryotherapy. The last four eyes were treated with a new conservative strategy of cyst aspiration (three cases) or local excision (one keratin "pearl" cyst), and endolaser photocoagulation of the collapsed cyst wall/base. All epithelial tissue was successfully eradicated by clinical criteria; one case required repeat excision (follow-up, 9 to 78 months, mean 45). Two eyes required later surgery for elevated IOP, two for cataract extraction and one for repeat PK. Final visual acuity ranged from 20/20 to hand motions, depending on associated ocular damage. Best-corrected visual results were obtained in the more conservatively managed eyes. Anterior chamber epithelial cysts can be managed conservatively in selected cases with good results. This strategy may be particularly useful in children's eyes, where preservation of the lens, iris, and other structures may facilitate amblyopia management. Copyright 2003 by Elsevier Science Inc.
Chung, Shiu-Dong; Wu, Chia-Chang; Lin, Victor Chia-Hsiang; Ho, Chen-Hsun; Yang, Stephen Shei Dei; Tsai, Yao-Chou
2011-08-01
In this study we present our experience using minilaparoscopic intracorporeal knot tying to ligate internal spermatic veins (ISV) while sparing the spermatic artery and lymphatics. Minilaparoscopic varicocelectomies were performed in 87 patients between January 2004 and January 2009. All varicoceles were detected clinically according to the World Health Organization (WHO) classification and confirmed by scrotal color Doppler ultrasonography. The surgical indications were scrotal symptoms in 71, infertility in 16, and both conditions in 2. Three 3.5 mm minilaparoscopic ports were used for the operation. The ISVs were dissected and then ligated with intracorporeal knot-tying. The testicular artery and lymphatic vessels were carefully preserved to minimize procedure-related complications. Unilateral laparoscopic varicocelectomy was performed in 21 (24.2%) patients and bilateral in 66 (75.8%). Mean operative time was 71.1 ± 29.2 and 46.8 ± 12.6 min for bilateral and unilateral varicocelectomies, respectively. All patients were discharged within 24 h after surgery. Neither immediate major nor late procedure-related complications were noted. Of the 71 patients with scrotal symptoms, the symptoms completely subsided in 55 (77.5%) and partially subsided in 10 (14.1%). Only one (1.2%) recurrent varicocele was detected within a mean follow-up of 21 months (range = 3-42). Neither hydrocele formation nor testicular atrophy was found during the follow-up period. Our 5-year experience revealed that minilaparoscopic varicocelectomy with sparing of artery and lymphatic vessels could safely and effectively ligate all spermatic veins and preserve spermatic arteries and lymphatic channels without leading to a high varicocele persistence or recurrence.
Management of persistent hyperplastic primary vitreous by pars plana vitrectomy.
Peyman, G A; Sanders, D R; Nagpal, K C
1976-11-01
Two children with persistent hyperplastic primary vitreous (PHPV) underwent vitrectomy and lensectomy via the pars plana to remove the fibrovascular stalk. Postoperatively the eyes were quiet, only a slight vitreous haze obscured the fundus view in the immediate postoperative period, and the stumps of the stalks retracted. Early surgical treatment of PHPV may prevent later serious complications.
Endophthalmitis following 27-Gauge Pars Plana Vitrectomy for Vitreous Floaters
Lin, Zhong; Wu, Rong Han; Moonasar, Nived
2016-01-01
Purpose To report a case of Staphylococcus epidermidis endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. Methods The clinical course and imaging findings, including fundus optomap, and spectral domain optical coherence tomography of a 24-year-old male patient were documented. Results The patient, with a preoperative best-corrected visual acuity (BCVA) of 1.0, developed endophthalmitis following 27-gauge pars plana vitrectomy for symptomatic vitreous floaters. After a series of treatments, including emergent vitreous tap and silicone oil injection, antibiotic treatment, and silicone oil removal, the patient regained a BCVA of 0.6. Conclusion Although rare, the potential risk of endophthalmitis should be explicitly discussed with patients considering surgical intervention for vitreous floaters. PMID:28101041
Toxic anterior segment syndrome outbreak after vitrectomy and silicone oil injection.
Moisseiev, Elad; Barak, Adiel
2012-01-01
To report a rare outbreak of toxic anterior segment syndrome (TASS) in 4 patients who underwent vitrectomy with silicone oil injection. Review of the medical charts of all patients who underwent surgery in the operating theater of our department during a 10-day period in May 2011. We report on 4 patients who developed TASS after vitrectomy with silicone oil injection. The clinical presentation was typical of TASS, and different from the anterior chamber reaction that may occur after silicone oil injection. All cases were treated effectively with topical steroids, and the outbreak stopped after the silicone oil batch was exchanged. We discuss the possible mechanisms for this unusual TASS outbreak, and suggest the silicone oil as its cause.
Grzybowski, Andrzej; Turczynowska, Magdalena; Kuhn, Ferenc
2017-12-02
Conducted in the early 1990s Endophthalmitis Vitrectomy Study (EVS) have helped in establishing reasonable guidelines for the management of infectious postoperative endophthalmitis. However at present, more than 20 years after its publication, tremendous progress has been introduced in vitrectomy technology, which now permits the vitreoretinal surgeon to perform surgery more safely, and with better outcomes. Moerover, performing a complete vitreous removal, along with the moving up of the surgical intervention to as early as possible allows the prevention of complications that would limit the functional improvement postoperatively. Thus, it is now highly needed to re-evaluate the conclusions of the EVS study. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Effect of three months of soft contact lens wear on conjunctival cytology.
Sapkota, Kishor; Franco, Sandra; Sampaio, Paula; Lira, Madalena
2016-07-01
The purpose of this study was to investigate the effect of three months of soft contact lens wear on conjunctival goblet cell density and epithelial cell morphology. This was a longitudinal clinical trial. Conjunctival impression cytology was performed on the superior palpebral conjunctiva in fifty-four eyes of twenty-seven neophyte contact lens wearers before and after three months of contact lens wear. Goblet cell density was determined by optical microscopy and epithelial cell morphology was classified according to the Tseng classification. Changes in goblet cell density as well as epithelial cell grading were determined. The effects of lens material and wearing modality on cytological changes were also investigated. Goblet cell density reduced significantly by 85 ± 151 cells/mm(2) (p < 0.001) after three months of contact lens wear. Reduction in goblet cell density was associated with lens materials; it was higher in conventional hydrogel lenses in comparison to silicone-hydrogel lenses (p = 0.008). The highest reduction in goblet cell density was found with Nelfilcon A lens wear (p = 0.002) and the lowest with Comfilcon A lens wear (p = 0.414). There was no statistically significant difference in grading of epithelial metaplasia before and after three months of contact lens wear (p = 0.075). Age was not correlated with the reduction in goblet cell density (r = -0.196, p = 0.160) but it was associated with the change in epithelial cell morphology (p = 0.036). Three months of soft contact lens wear statistically significantly reduced goblet cell density; however, no significant changes were found in the grading of epithelial metaplasia. Contact lenses with lower oxygen permeability, higher Young modulus and higher thickness highly affected the conjunctival cytology. © 2016 Optometry Australia.
Kolozsvári, Bence L; Losonczy, Gergely; Pásztor, Dorottya; Fodor, Mariann
2017-01-13
Toric intraocular lens (IOL) implantation can be an effective method for correcting corneal astigmatism in patients with vitreoretinal diseases and cataract. Our purpose is to report the outcome of toric IOL implantation in two cases - a patient with scleral-buckle-induced regular corneal astigmatism and a patient with keratoconus following pars plana vitrectomy. As far as we are aware, there are no reported cases of toric IOL implantation in a vitrectomized eye with keratoconus nor of toric IOL implantation in patients with scleral-buckle-induced regular corneal astigmatism. Two patients with myopia and high corneal astigmatism underwent cataract operation with toric IOL implantation after posterior segment surgery. Myopia and high astigmatism (>2.5 diopter) were caused by previous scleral buckling in one case and by keratoconus in the other case. Pre- and postoperative examinations during the follow-up of included uncorrected and spectacle corrected distance visual acuity (UCDVA/CDVA), automated kerato-refractometry (Topcon), Pentacam HR, IOL Master (Zeiss) axial length measurements and fundus optical coherence tomography (Zeiss). One year postoperatively, the UCDVA and CDVA were 20/25 and 20/20 in both cases, respectively. The absolute residual refractive astigmatism was 1.0 and 0.75 Diopters, respectively. The IOL rotation was within 3° in both eyes, therefore IOL repositioning was not necessary. Complications were not observed in our cases. These cases demonstrate that toric IOL implantation is a predictable and safe method for the correction of high corneal astigmatism in complicated cases with different origins. Irregular corneal astigmatism in keratoconus or scleral-buckle-induced regular astigmatisms can be equally well corrected with the use of toric IOL during cataract surgery. Previous scleral buckling or pars plana vitrectomy seem to have no impact on the success of the toric IOL implantation, even in keratoconus. IOL rotational stability and refractive predictability in patients with a previous vitreoretinal surgery can be as good as in uncomplicated cases.
Deuchler, Svenja; Wagner, Clemens; Singh, Pankaj; Müller, Michael; Al-Dwairi, Rami; Benjilali, Rachid; Schill, Markus; Ackermann, Hanns; Bon, Dimitra; Kohnen, Thomas; Schoene, Benjamin; Koss, Michael; Koch, Frank
2016-01-01
Purpose To evaluate the efficacy of the virtual reality training simulator Eyesi to prepare surgeons for performing pars plana vitrectomies and its potential to predict the surgeons’ performance. Methods In a preparation phase, four participating vitreoretinal surgeons performed repeated simulator training with predefined tasks. If a surgeon was assigned to perform a vitrectomy for the management of complex retinal detachment after a surgical break of at least 60 hours it was randomly decided whether a warmup training on the simulator was required (n = 9) or not (n = 12). Performance at the simulator was measured using the built-in scoring metrics. The surgical performance was determined by two blinded observers who analyzed the video-recorded interventions. One of them repeated the analysis to check for intra-observer consistency. The surgical performance of the interventions with and without simulator training was compared. In addition, for the surgeries with simulator training, the simulator performance was compared to the performance in the operating room. Results Comparing each surgeon’s performance with and without warmup trainingshowed a significant effect of warmup training onto the final outcome in the operating room. For the surgeries that were preceeded by the warmup procedure, the performance at the simulator was compared with the operating room performance. We found that there is a significant relation. The governing factor of low scores in the simulator were iatrogenic retinal holes, bleedings and lens damage. Surgeons who caused minor damage in the simulation also performed well in the operating room. Conclusions Despite the large variation of conditions, the effect of a warmup training as well as a relation between the performance at the simulator and in the operating room was found with statistical significance. Simulator training is able to serve as a warmup to increase the average performance. PMID:26964040
Yokokura, Shunji; Hariya, Takehiro; Kobayashi, Wataru; Meguro, Yasuhiko; Nishida, Kohji; Nakazawa, Toru
2017-03-01
We describe a technique for the penetrating keratoplasty (PKP) triple procedure that uses 29-gauge dual-chandelier illumination during creation of a non-open-sky continuous curvilinear capsulorhexis (CCC). The chandeliers are inserted through the pars plana into the vitreous cavity through the bulbar conjunctiva at the 3 o'clock and 9 o'clock positions. We compared this approach with that of a core vitrectomy, in which a single 25-gauge port is inserted into the vitreous cavity transconjunctivally through the upper temporal pars plana. The area of halation around the corneal opacity was significantly smaller in the 29-gauge group than in the 25-gauge group. The reduction in halation improved visibility of the anterior capsule and enabled the surgeon to perform CCC with greater safety. The 29-gauge chandelier system was more suitable than the 25-gauge chandelier system for the non-open-sky CCC component of the PKP triple procedure. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Ab interno management of blocked Ahmed valve in the posterior segment.
Odrich, Steven; Wald, Kenneth; Sperber, Laurence
2013-01-01
To report a case of late failure of a posterior segment placed Ahmed valve in a uveitic eye with a corneal graft and a minimally invasive, ab interno approach in restoring valve function, pressure control, and preservation of vision. Case report. A 25 gauge trans-conjunctival 3-port pars plana vitrectomy was performed to inspect and clean the ostium of the Ahmed valve of any vitreous debris. The Ahmed valve was not disturbed externally and conjunctival dissection was not performed. A 27-gauge blunt cannula was introduced through the vitrector site and used to cannulate the tube and flush it with balanced salt solution. A bleb was immediately re-established and all instruments were removed requiring no sutures. Intraocular pressure returned to target levels and a filtration bleb was re-established. Corneal graft clarity was restored with resolution of preoperative microcystic edema. Postoperative inflammation was minimal and vision was restored. A nonfunctioning tube shunt residing in the vitreous cavity may be revised ab interno without disturbing the shunt placement or the conjunctiva under which it resides to re-establish filtration.
Endogenous Aspergillus endophthalmitis. Clinical features and treatment outcomes.
Weishaar, P D; Flynn, H W; Murray, T G; Davis, J L; Barr, C C; Gross, J G; Mein, C E; McLean, W C; Killian, J H
1998-01-01
This study evaluated the clinical features and treatment outcomes in patients with endogenous Aspergillus endophthalmitis. The study design was a multicenter retrospective chart review. Ten patients (12 eyes) with culture-proven endogenous Aspergillus endophthalmitis treated by 1 of the authors were studied. Intravitreous amphotericin B injection, pars plana vitrectomy, systemic amphotericin B therapy, and oral anti-fungal therapy were performed. Elimination of endogenous Aspergillus endophthalmitis and Snellen visual acuity, best corrected, were measured. All patients had a 1- to 3-day history of pain and marked loss of visual acuity in the involved eyes. Varying degrees of vitritis was present in all 12 eyes. In 8 of 12 eyes, a central macular chorioretinal inflammatory lesion was present. Four patients (six eyes) had associated pulmonary diseases and were receiving concurrent steroid therapy. One of these patients with chronic asthma also was abusing intravenous drugs. Overall, six patients (six eyes) had a history of intravenous drug abuse, whereas a seventh patient (one eye) was suspected of abusing intravenous drugs. Blood cultures and echocardiograms were negative for systemic aspergillosis. Management consisted of a pars plana vitrectomy in 10 of 12 eyes. Intravitreous amphotericin B was administered in 11 of 12 eyes. Systemic amphotericin B therapy was used in eight patients. One patient was treated with oral antifungal agents. In three eyes without central macular involvement, final visual acuities were 20/25 to 20/200. In eight eyes with initial central macular involvement, final visual acuities were 20/400 in three eyes and 5/200 or less in four eyes. Two painful eyes with marked inflammation, hypotony, and retinal detachment were enucleated. Endogenous Aspergillus endophthalmitis usually has an acute onset of intraocular inflammation and often has a characteristic chorioretinal lesion located in the macula. Although treatment with pars plana vitrectomy and intravitreous amphotericin B is capable of eliminating the ocular infection, the visual outcome generally is poor, especially when there is direct macular involvement.
Comparison of Topical Versus Peribulbar Anesthesia for 23G Pars Plana Vitrectomy.
Chaudhary, Rizwan Ahmad; Khaqan, Hussain Ahmad; Ahmad, Ayesha; Imtiaz, Usman; Raza, Hassan; Shabbir, Usman
2018-06-01
To compare the safety and efficacy of topical anesthesia versus peribulbar anesthesia for 23-gauge pars plana vitrectomy. Randomized controlled trial. Ophthalmology Department, Lahore General Hospital, Ameer-ud-Din Medical College, Postgraduate Medical Institute, Lahore from April 2013 to March 2016. A total of 110 patients were equally divided (n=55) in group A (topical anesthesia) and group B (peribulbar anesthesia). In group A, pledget soaked with 0.5% proparacaine hydrochloride were placed in the superior and inferior fornices three minutes before surgery, and removed just before surgery. For group B patients, 3 ml of 0.5% bupivacaine was used for peribulbar anesthesia three minutes before surgery. Surgical time was noted from the placement of pledget in fornix till the eye pad placed in group A, and from the time of peribulbar anesthesia in group B till the eye pad placed at the end of surgery. All data was recorded in Excel sheet and p-values were calculated using online OpenEpi. The mean age of the patient was 56.28 ±13.76 years. Male patients were 78 (70.9%) and female patients were 32 (29.1%). Mean duration of surgery was 30.32 ±7.07 minutes and mean pain score was 2.30 ±0.98. There was a significant difference with respect to mean duration of surgery in patients who were given topical anesthesia (32.52 ±6.92 minutes) versus those given peribulbar anesthesia (28.12 ±6.57 minutes, p<0.001). Mean pain score in topical anesthesia group (3.11 ±0.89) was significantly higher as compared to peribulbar anesthesia group (2.67 ±0.91, p=0.011). Topical anesthesia is as effective as peribulbar anesthesia in terms of patient comfort and duration of surgery for 23-G pars plana vitrectomy in patients with vitreous hemorrhage.
Effects of kallidinogenase in patients undergoing vitrectomy for diabetic macular edema.
Yoshizumi, Yuki; Ohara, Zaigen; Tabuchi, Hitoshi; Sumino, Hitomi; Maeda, Yukiko; Mochizuki, Hideki; Yamane, Ken; Kiuchi, Yoshiaki
2018-05-12
To evaluate the effectiveness of the combination of vitrectomy with kallidinogenase for diabetic macular edema (DME). This study was designed as a prospective, randomized, multicenter study comparing 19 eyes of 19 patients who received 150 units of kallidinogenase administered a day for 52 weeks from the day after vitrectomy (study group) with 20 eyes of 20 patients who received no kallidinogenase (control group). The main outcome measurements included logMAR visual acuity and central foveal thickness (CFT) before surgery and at 3, 6, 9, and 12 months after vitrectomy. During follow-up, 11 patients dropped out (six in the study group and five in the control group), leaving 28 eyes in 28 patients for analysis (13 in the study group and 15 in the control group). Visual acuity improved significantly at 12 months in both groups compared with before surgery. The degree of improvement did not differ significantly between the groups. At 12 months, the mean CFT decreased significantly in both groups, with no significant difference in the rate of change between the two groups. In the study group, the visual acuity and CFT significantly improved from 3 to 12 months and from 6 to 12 months, whereas these parameters did not continue to improve in the control group after 6 months (for visual acuity) or 3 months (for CFT). After vitrectomy for DME, visual acuity and CFT improved significantly in both groups, but only patients treated with kallidinogenase continued to have significant improvement throughout the study period.
Management of persistent hyperplastic primary vitreous by pars plana vitrectomy.
Peyman, G A; Sanders, D R; Nagpal, K C
1976-01-01
Two children with persistent hyperplastic primary vitreous (PHPV) underwent vitrectomy and lensectomy via the pars plana to remove the fibrovascular stalk. Postoperatively the eyes were quiet, only a slight vitreous haze obscured the fundus view in the immediate postoperative period, and the stumps of the stalks retracted. Early surgical treatment of PHPV may prevent later serious complications. Images PMID:1009053
Suic, S P; Sikić, J
2001-01-01
We measured the tamponading effect of silicone oil, saline and air after vitrectomy, on intraocular pressure and aqueous humor outflow in 85 patients with highly proliferative retina and vitreous changes. Silicone oil as retinal tamponading agent after vitrectomy was used in 45 patients, and saline or air in 39 patients. The mean intraocular pressure measured at one month after treatment was greatly elevated in patients with silicone oil tamponade as compared to those with saline or air tamponade. At 6 and 12 months examinations, mean intraocular pressures were compared in these two groups of patients. Gonioscopy revealed silicone oil emulsification and presence of emulsified bubbles in the anterior chamber in 22.22% of patients, and narrowing of the chamber angle in several patients with silicone oil tamponade. Intraocular pressure elevation following vitrectomy with silicone oil tamponade was found to be of transient rather than permanent nature, since it regressed after silicone oil removal. This transient elevation was due to silicone oil tendency to emulsify. Silicone oil bubbles changed the morphology of the anterior chamber angle and fine trabecular structures by creating a barrier to aqueous humor outflow.
Lee, Yongeun; Kang, Seungbum; Park, Young-Hoon
2013-02-01
To evaluate the effect of adjunctive subtenon injection of triamcinolone acetonide (TA) in gas-filled eyes after vitrectomy for complicated proliferative diabetic retinopathy (PDR). This nonrandomized comparative study included 27 patients (27 eyes) who underwent pars plana vitrectomy and gas tamponade for treatment of PDR with tractional or combined tractional-rhegmatogenous retinal detachment and who received subtenon injection of TA (40 mg) at the end of surgery. The study group was compared with the control group (29 eyes), which was matched with the study group for preoperative and intraoperative parameters, but underwent pars plana vitrectomy and gas tamponade without a subtenon injection of TA. Retinal reattachments without reoperation were achieved in 25 eyes (92.6%) and 26 eyes (89.7%) at 6 months (p = 1.000) in the study and control groups, respectively. The study group and the control group did not differ significantly in the frequency of postoperative proliferative vitreoretinopathy, retinal redetachment rate, reoperation rate, macular pucker formation, postoperative vitreous hemorrhage, gain in visual acuity, intraocular pressure, and intraocular inflammation (p > 0.05). The clinical results of pars plana vitrectomy for complicated PDR are not improved significantly by an adjunctive subtenon TA injection in gas-filled eyes.
Rizzo, Stanislao; Fantoni, Gualtiero; de Santis, Giovanni; Lue, Jaw-Chyng Lormen; Ciampi, Jonathan; Palla, Michele; Genovesi Ebert, Federica; Savastano, Alfonso; De Maria, Carmelo; Vozzi, Giovanni; Brant Fernandes, Rodrigo A; Faraldi, Francesco; Criscenti, Giuseppe
2017-09-01
Thorough this experimental study, the physic features of a modified 23-gauge vitrectomy probe were evaluated in vitro. A modified vitrectomy probe to increase vitreous outflow rate with a small-diameter probe, that also minimized tractional forces on the retina, was created and tested. The "new" probe was created by drilling an opening into the inner duct of a traditional 23-gauge probe with electrochemical or electrodischarge micromachining. Both vitreous outflow and tractional forces on the retina were examined using experimental models of vitreous surgery. The additional opening allowed the modified probe to have a cutting rate of 5,000 cuts per minute, while sustaining an outflow approximately 45% higher than in conventional 23-gauge probes. The modified probe performed two cutting actions per cycle, not one, as in standard probes. Because tractional force is influenced by cutting rate, retinal forces were 2.2 times lower than those observed with traditional cutters. The modified probe could be useful in vitreoretinal surgery. It allows for faster vitreous removal while minimizing tractional forces on the retina. Moreover, any available probe can be modified by creating a hole in the inner duct.
Song, Ji Hun; Jang, Seran; Cho, Eun Hyung; Ahn, Jaehong
2017-05-01
When vitrectomy is performed in eyes that have undergone glaucoma surgery, the site of sclerotomy often overlaps with the previous glaucoma operation site. It can lead to serious complications such as postoperative hypotony, leakage, and/or infection. Our technique involves modification of surgeon's position and two sclerotomy sites 45° away from the original position, with an infusion cannula inserted infranasally to avoid damage to the glaucoma drainage implant or filtering bleb. The modified approach was applied to seven eyes with various indications. Vitrectomy was successfully completed, and there were no sclerotomy site complications, leakage, or hypotony in any case. Good intraocular pressure control was maintained throughout the postoperative course in all cases. © Copyright: Yonsei University College of Medicine 2017.
A two-in-one Faraday rotator mirror exempt of active optical alignment.
Wan, Qiong; Wan, Zhujun; Liu, Hai; Liu, Deming
2014-02-10
A two-in-one Faraday rotator mirror was presented, which functions as two independent Faraday rotation mirrors with a single device. With the introduction of a reflection lens as substitution of the mirror in traditional structure, this device is characterized by exemption of active optical alignment for the designers and manufacturers of Faraday rotator mirrors. A sample was fabricated by passive mechanical assembly. The insertion loss was measured as 0.46 dB/0.50 dB for the two independent ports, respectively.
Bai, Hua; Huang, Yi-fei; Wang, Li-qiang
2013-10-01
This study was to evaluate clinical results of two types soft one-piece keratoprosthesis (KPros) made of PHEMA implanted to alkali burned rabbit corneas. Experimental study. Twelve pieces KPros were implanted alkali burned rabbit corneas(type I and II, 6 pieces respectively). The examinations including slit-lamp, fundus photography,B-ultrasound and ultrasound biomicroscopy (UBM) were carried out. All Kpros were stable and no complications happened including conjunctiva flap dehiscence, aqueous leak and infection. IOP were normal by finger touch. B-ultrasound show no retina detachment and UBM show synechia in most animals (10 case). Retroprosthetic membrane happened in type I (3 case) . Visible conjunctiva hyperplasia covering the optical region happened in all KPros. (1) The same material, integrated design, maybe eliminating the material interface problem. (2)Simple surgical skills. (3)IOP measurement is possible because of soft material. (4)KPro I do not need removal of the lens and vitrectomy. The projecting portion of KPro II may reduce the incidence of proliferative membrane. Long term effects need more cases and further observation.
Schulz-Key, Steffen; Carlsson, Jan-Olof; Crafoord, Sven
2011-03-01
Floaters caused by degenerative or postoperative changes in the vitreous can interfere with all aspects of visual functioning. The aim of this study is to report the longterm outcome of pars plana vitrectomy (PPV) for persistent vitreous opacities. In a retrospective, non-randomized, interventional case study we reviewed all cases of vitreous floaters that were vitrectomized at our department between 1997 and 2006. Patient complaints and satisfaction were assessed by a questionnaire administered at the end of follow-up. Seventy-three consecutive cases were included (61 patients). Mean Snellen best corrected visual acuity (BCVA) before surgery was 0.81. Overall, 85% of patients complained of severe or very severe difficulty caused by floaters. A total of 42% of eyes were pseudophakic, four of which were operated with combined PPV and phacoemulsification. Mean follow-up time was 37 months. Of the phakic eyes, 60% were operated for cataract during follow-up. One retinal detachment (RD) occurred immediately postoperatively (1.3%) and another four eyes developed RD during longterm follow-up 24-44 months after PPV (5.5% of cases). Postoperative BCVA remained mostly unchanged. Overall, 88% of patients were satisfied with the results of the operation. Some patients make considerable complaints as a result of vitreous opacities and their distress does not correlate with visual acuity. Vitrectomy is a safe and effective procedure with which to help these patients. Patients should be informed about the risk of cataract progression, unexpected inflammatory reaction and an increased risk for RD several years after PPV (5.5%). © 2009 The Authors. Journal compilation © 2009 Acta Ophthalmol.
Early surgical treatment of retinal hemangioblastomas.
van Overdam, Koen A; Missotten, Tom; Kilic, Emine; Spielberg, Leigh H
2017-02-01
To evaluate the clinical course after early surgical treatment with excision of retinal hemangioblastomas (RHs) before development of major complications. Interventional case series of four eyes (four patients) with a peripheral RH that had not yet been treated by laser or cryotherapy prior to surgery. All eyes underwent 23-gauge vitrectomy with lesion excision. One patient underwent ligation of the feeder vessel prior to lesion excision. Best-corrected visual acuity and clinical course were assessed during a follow-up period of at least 4 years. Four patients (mean age 27.3 years; range 19-32) were included, of whom two had von Hippel-Lindau syndrome. Visual acuity improved in three patients (mean 4.8 lines; range 3-10) and remained stable at 0.0 logMAR in one patient. There were no intraoperative complications. Postoperative complications included transient mild vitreous haemorrhage (n = 2), and local epiretinal membrane formation at the excision location (n = 1). At 4 years postoperatively, there were no long-term complications. There was one case of a new lesion, which was effectively treated with laser. Vitrectomy with RH excision seems to be an effective approach for larger RHs and could be considered an early treatment option in selected cases. Postoperative complications were limited in scope of this case series. Important points to consider during vitrectomy are effective closure of feeder and draining vessels as well as complete removal of posterior hyaloid and epiretinal membranes in order to avoid postoperative vitreous haemorrhage and proliferative vitreoretinopathy. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Citirik, Mehmet; Kabatas, Emrah Utku; Batman, Cosar; Akin, Kadir Okhan; Kabatas, Naciye
2012-01-01
To assess vitreous vascular endothelial growth factor (VEGF) concentrations in proliferative diabetic retinopathy (PDR) in comparison to proliferative vitreoretinopathy (PVR). Vitreous samples were collected from 69 eyes of 69 patients with traumatic lens dislocation (n = 10), grade B PVR with rhegmatogenous retinal detachment (n = 13), grade C PVR with rhegmatogenous retinal detachment (n = 14), PDR with vitreous hemorrhage (n = 18), and PDR with vitreous hemorrhage and tractional retinal detachment (n = 14). Vitreous fluid samples were obtained at vitrectomy, and the levels of VEGF were measured by enzyme-linked immunosorbent assay. The mean vitreous level of VEGF was 15.14 ± 5.22 pg/ml in eyes with grade B PVR, 99.15 ± 38.58 pg/ml in eyes with grade C PVR, 4,534.01 ± 1,193.28 pg/ml in eyes with vitreous hemorrhage secondary to PDR, 5,157.29 ± 969.44 pg/ml in eyes with vitreous hemorrhage and tractional retinal detachment secondary to PDR, and 16.19 ± 5.76 pg/ml in eyes of the control group with traumatic lens dislocation. Vitreous VEGF concentrations were significantly higher in the patients with grade C PVR, PDR with vitreous hemorrhage and PDR with vitreous hemorrhage and tractional retinal detachment in comparison to the control patients (p < 0.05). A significant alteration was not observed in patients with grade B PVR (p = 0.55). Vitreous VEGF concentrations are increased in PDR and grade C PVR. The high VEGF concentrations could suggest a possible effect of VEGF on advanced PVR. Copyright © 2011 S. Karger AG, Basel.
Diabetic retinopathy and complexity of retinal surgery in a general hospital.
Mijangos-Medina, Laura Fanny; Hurtado-Noriega, Blanca Esmeralda; Lima-Gómez, Virgilio
2012-01-01
Usual retinal surgery (vitrectomy or surgery for retinal detachment) may require additional procedures to deal with complex cases, which increase time and resource use and delay access to treatment. We undertook this study to identify the proportion of primary retinal surgeries that required complex procedures and the associated causes. We carried out an observational, descriptive, cross-sectional, retrospective study. Patients with primary retinal surgery were evaluated (January 2007-December 2010). The proportion and 95% confidence intervals (CI) of preoperative diagnosis and cause of the disease requiring retinal surgery as well as the causes for complex retinal surgery were identified. Complex retinal surgery was defined as that requiring lens extraction, intraocular lens implantation, heavy perfluorocarbon liquids, silicone oil tamponade or intravitreal drugs, in addition to the usual surgical retinal procedure. The proportion of complex retinal surgeries was compared among preoperative diagnoses and among causes (χ(2), odds ratio [OR]). We studied 338 eyes. Mean age of subjects was 53.7 years, and there were 49% females. The most common diagnoses were vitreous hemorrhage (27.2%) and rhegmatogenous retinal detachment (24.6%). The most common cause was diabetes (50.6%); 273 eyes required complex surgery (80.8%, 95% CI: 76.6-85). The proportion did not differ among diagnoses but was higher in diabetic retinopathy (89%, p <0.001, OR 3.04, 95% CI: 1.63-5.7). Of the total sample, 80.8% of eyes required complex surgical procedures; diabetic retinopathy increased by 3-fold the probability of requiring these complex procedures. Early treatment of diabetic retinopathy may reduce the proportion of complex retinal surgery by 56%.
Solid phase microextraction field kit
Nunes, Peter J.; Andresen, Brian D.
2005-08-16
A field kit for the collection, isolation and concentration of trace amounts of high explosives (HE), biological weapons (BW) and chemical weapons (CW) residues in air, soil, vegetation, swipe, and liquid samples. The field kit includes a number of Solid Phase Microextraction (SPME) fiber and syringe assemblies in a hermetically sealed transportation container or tubes which includes a sampling port, a number of extra SPME fiber and syringe assemblies, the fiber and syringe assemblies including a protective cap for the fiber, and an extractor for the protective cap, along with other items including spare parts, protective glove, and an instruction manual, all located in an airtight container.
Vitrectomy outcomes in eyes with diabetic macular edema and vitreomacular traction.
Haller, Julia A; Qin, Haijing; Apte, Rajendra S; Beck, Roy R; Bressler, Neil M; Browning, David J; Danis, Ronald P; Glassman, Adam R; Googe, Joseph M; Kollman, Craig; Lauer, Andreas K; Peters, Mark A; Stockman, Margaret E
2010-06-01
To evaluate vitrectomy for diabetic macular edema (DME) in eyes with at least moderate vision loss and vitreomacular traction. Prospective cohort study. The primary cohort included 87 eyes with DME and vitreomacular traction based on investigator's evaluation, visual acuity 20/63-20/400, optical coherence tomography (OCT) central subfield >300 microns and no concomitant cataract extraction at the time of vitrectomy. Surgery was performed according to the investigator's usual routine. Follow-up visits were performed after 3 months, 6 months (primary end point), and 1 year. Visual acuity, OCT retinal thickening, and operative complications. At baseline, median visual acuity in the 87 eyes was 20/100 and median OCT thickness was 491 microns. During vitrectomy, additional procedures included epiretinal membrane peeling in 61%, internal limiting membrane peeling in 54%, panretinal photocoagulation in 40%, and injection of corticosteroids at the close of the procedure in 64%. At 6 months, median OCT central subfield thickness decreased by 160 microns, with 43% having central subfield thickness <250 microns and 68% having at least a 50% reduction in thickening. Visual acuity improved by > or =10 letters in 38% (95% confidence interval, 28%-49%) and deteriorated by > or =10 letters in 22% (95% confidence interval, 13%-31%). Postoperative complications through 6 months included vitreous hemorrhage (5 eyes), elevated intraocular pressure requiring treatment (7 eyes), retinal detachment (3 eyes), and endophthalmitis (1 eye). Few changes in results were noted between 6 months and 1 year. After vitrectomy performed for DME and vitreomacular traction, retinal thickening was reduced in most eyes. Between 28% and 49% of eyes with characteristics similar to those included in this study are likely to have improvement of visual acuity, whereas between 13% and 31% are likely to have worsening. The operative complication rate is low and similar to what has been reported for this procedure. These data provide estimates of surgical outcomes and serve as a reference for future studies that might consider vitrectomy for DME in eyes with at least moderate vision loss and vitreomacular traction. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Packer, Mark
2016-01-01
The purpose of this review is to summarize relevant data from publications appearing in the peer-reviewed scientific literature over the past decade since US Food and Drug Administration approval of the implantable collamer lens (ICL), and, in particular, to review studies relating to sizing methodology, safety, and effectiveness, as well as more recent studies reporting clinical outcomes of the V4c Visian ICL with KS Aquaport, VICMO. A literature search was conducted using two databases, PubMed.gov and Science.gov, to identify all articles published after 2005 related to the Visian ICL (STAAR Surgical, Inc.). Articles were examined for their relevance to sizing methodology, clinical safety, and effectiveness, and the references cited in each article were also searched for additional relevant publications. The literature review revealed that all currently reported methods of determining the best-fit size of the ICL achieve similarly satisfactory results in terms of vault, the safe distance between the crystalline lens and the ICL. Specifically, meta-analysis demonstrated that sulcus-to-sulcus and white-to-white measurement-based sizing methods do not result in clinically meaningful nor statistically significant differences in vault (two-sample two-sided t-test using pooled mean and standard deviations; t (2,594)=1.33; P=0.18). The reported rates of complications related to vault are very low, except in two case series where additional risk factors such as higher levels of myopia and older age impacted the incidence of cataract. On the basis of preclinical studies and initial clinical reports, with up to 5 years of follow-up, the new VICMO central port design holds promise for further reduction of complications. Given its safety record and the significant improvement in vision and quality of life that the ICL makes possible, the benefits of ICL implantation outweigh the risks. PMID:27354760
Packer, Mark
2016-01-01
The purpose of this review is to summarize relevant data from publications appearing in the peer-reviewed scientific literature over the past decade since US Food and Drug Administration approval of the implantable collamer lens (ICL), and, in particular, to review studies relating to sizing methodology, safety, and effectiveness, as well as more recent studies reporting clinical outcomes of the V4c Visian ICL with KS Aquaport, VICMO. A literature search was conducted using two databases, PubMed.gov and Science.gov, to identify all articles published after 2005 related to the Visian ICL (STAAR Surgical, Inc.). Articles were examined for their relevance to sizing methodology, clinical safety, and effectiveness, and the references cited in each article were also searched for additional relevant publications. The literature review revealed that all currently reported methods of determining the best-fit size of the ICL achieve similarly satisfactory results in terms of vault, the safe distance between the crystalline lens and the ICL. Specifically, meta-analysis demonstrated that sulcus-to-sulcus and white-to-white measurement-based sizing methods do not result in clinically meaningful nor statistically significant differences in vault (two-sample two-sided t-test using pooled mean and standard deviations; t (2,594)=1.33; P=0.18). The reported rates of complications related to vault are very low, except in two case series where additional risk factors such as higher levels of myopia and older age impacted the incidence of cataract. On the basis of preclinical studies and initial clinical reports, with up to 5 years of follow-up, the new VICMO central port design holds promise for further reduction of complications. Given its safety record and the significant improvement in vision and quality of life that the ICL makes possible, the benefits of ICL implantation outweigh the risks.
Xu, Wu; Wang, Yang; Song, Jianping; Mo, Lanying; Jiang, Tao
2017-01-01
To further understand the effects of video-assisted thoracic surgery (VATS) with one-port versus three-port VATS for primary spontaneous pneumothorax (PSP). In this study, we searched information from the PubMed, Cochrane Library, Embase, ScienceDirect, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang Data databases from inception to September 2015 to collect data of randomized controlled trials (RCTs) and cohort studies about one-port VATS versus three-port VATS for PSP. Two independent authors were committed to screen literature, extract data, and assess the risk of bias of related studies. Then, we used the RevMan 5.20 software for a meta-analysis of one-port VATS versus three-port VATS for PSP. Six cohort studies involving 310 patients were finally selected in this meta-analysis. The results of our study indicate that one-port VATS had a shorter hospital stay (SMD = -0.39, 95 % CI -0.69 to 0.09, P = 0.01), lower VAS score of 24-h post-operative pain (SMD = -0.78, 95 % CI -1.40 to -0.52, P < 0.00001), shorter chest drainage time (SMD = -0.68, 95 % CI -1.15 to -0.22, P = 0.004), and lower incidence of post-operative paraesthesia (OR = 0.13, 95 % CI 0.06 to 0.29, P < 0.00001) compared with three-port VATS. However, one-port VATS had a lower patient satisfaction score at 24 h (SMD = -0.65, 95 % CI -0.95 to -0.35, P < 0.0001) and 48 h (SMD = -0.46, 95 % CI -0.71 to -0.21, P = 0.0002). No differences in the recurrence of pneumothorax (OR = 0.58, 95 % CI 0.20 to 1.67, P = 0.32), the operation time (SMD = 1.01, 95 % CI -4.63 to 2.60, P = 0.58), and the satisfaction score at 72 h (SMD = -0.11, 95 % CI -0.44 to 0.22, P < 0.00001) were noted between the groups. Current evidence suggests that one-port VATS may have certain advantages over three-port VATS for PSP. More large-scale and high-quality studies are needed for authentication.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Groth, M; Ellis, R; Brooks, N
A video camera system is described that measures the spatial distribution of visible line emission emitted from the main scrape-off layer (SOL) of plasmas in the DIII-D tokamak. A wide-angle lens installed on an equatorial port and an in-vessel mirror which intercepts part of the lens view provide simultaneous tangential views of the SOL on the low-field and high-field sides of the plasma's equatorial plane. Tomographic reconstruction techniques are used to calculate the 2-D poloidal profiles from the raw data, and 1-D poloidal profiles simulating chordal views of other optical diagnostics from the 2-D profiles. The 2-D profiles can bemore » compared with SOL plasma simulations; the 1-D profiles with measurements from spectroscopic diagnostics. Sample results are presented which elucidate carbon transport in plasmas with toroidally uniform injection of methane and argon transport in disruption mitigation experiments with massive gas jet injection.« less
Displacement of the retina and its recovery after vitrectomy in idiopathic epiretinal membrane.
Nitta, Eri; Shiraga, Fumio; Shiragami, Chieko; Fukuda, Kouki; Yamashita, Ayana; Fujiwara, Atsushi
2013-06-01
To study the displacement of the retina and its change after vitrectomy in idiopathic epiretinal membrane (ERM). Prospective, interventional case series. Fifty-six eyes of 53 consecutive patients with ERM underwent vitrectomy with ERM removal and internal limiting membrane peeling. Fundus autofluorescence (FAF) imaging was examined before and at 1, 3, 6, and 12 months after vitrectomy. Main outcome measures were the proportion of eyes with retinal displacement for ERM detected by FAF imaging and the recovery rate of retinal displacement after vitrectomy. Before surgery, FAF photography demonstrated hyperautofluorescent lines within the vascular arcade in 37 (66.1%) of the 56 eyes. The lines seemed to be consistent with the location of the retinal vessels before their displacement. These hyperautofluorescent lines appeared significantly more frequently among patients in whom the disease duration was 3 years or less. In 23 (62.2%) of these 37 eyes, within the first postoperative month, the hyperautofluorescent lines disappeared. The disappearance of the hyperautofluorescent line was thought to be the result of the return of the retinal vessel to its original position. Greater visual improvements (logarithm of the minimal angle of resolution, ≥0.3) were statistically significantly obtained in patients in whom the hyperautofluorescent lines had become indistinct at 1 month after surgery (P < .05). Hyperautofluorescent lines indicating retinal displacement were found by FAF in 66.1% of patients before surgery for ERM. In addition, retinal displacement was significantly more common among patients who had experienced subjective symptoms for 3 years or less. Fundus autofluorescence is useful for predicting postoperative visual acuity improvement. Copyright © 2013 Elsevier Inc. All rights reserved.
Optical coherence tomography in optic pit maculopathy managed with vitrectomy-laser-gas.
García-Arumí, José; Guraya, Borja Corcóstegui; Espax, Ana Boixadera; Castillo, Vicente Martínez; Ramsay, Laura Sararols; Motta, R Max
2004-10-01
Optic disc pit (ODP) maculopathy has a poor visual prognosis if left to its natural course. Several therapeutic approaches have been attempted. The cases of 11 patients evaluated with optical coherence tomography (OCT) and treated with vitrectomy-laser-gas and their functional and anatomical outcomes are presented. Retrospective interventional consecutive case series, including 11 eyes with ODP maculopathy. Pre- and postoperative best-corrected visual acuity (BCVA), OCT and angiography were recorded. All patients underwent pars plana vitrectomy, posterior hyaloid dissection peripapillary diode laser prior to retinal reapplication and C(3)F(8) 15% injection. Mean preoperative BCVA was 20/126. Median preoperative BCVA was 1.0 LogMAR (range 1.3-0.4) . Eighty-two per cent of patients gained 2 or more Snellen lines of vision (mean 4.4 lines gained). Mean final BCVA was 20/32, and median final BCVA was 20/30 in Snellen VA and 0.2 in LogMAR (range 0.7-0) Preoperative OCT in all but one case confirmed the bilaminar structure of the macular detachment. Postoperative OCT helped in monitoring reabsorption of the macular detachment, which was achieved in all cases after an average of 6.5 months post-surgery. BCVA increased progressively as the subretinal fluid was reabsorbed (P=0.006). Mean duration of postoperative follow-up was 15 months. Recurrence was observed in two cases. In our series, the vitrectomy-laser-gas procedure for ODP maculopathy improved vision and achieved satisfactory anatomic results in all 11 cases. OCT was useful in the diagnosis and follow-up of this pathology. However, the low incidence of this entity makes it difficult to obtain series large enough to determine the efficacy of the vitrectomy-laser-gas procedure and other treatment modalities and be able to suggest a procedure of choice.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seppala, L G
2000-09-15
A glass-choice strategy, based on separately designing an achromatic lens before progressing to an apochromatic lens, simplified my approach to solving the International Optical Design Conference (IODC) 1998 lens design problem. The glasses that are needed to make the lens apochromatic are combined into triplet correctors with two ''buried'' surfaces. By applying this strategy, I reached successful solutions that used only six glasses--three glasses for the achromatic design and three additional glasses for the apochromatic design.
Technical and instrumental prerequisites for single-port laparoscopic solo surgery: State of art
Kim, Say-June; Lee, Sang Chul
2015-01-01
With the aid of advanced surgical techniques and instruments, single-port laparoscopic surgery (SPLS) can be accomplished with just two surgical members: an operator and a camera assistant. Under these circumstances, the reasonable replacement of a human camera assistant by a mechanical camera holder has resulted in a new surgical procedure termed single-port solo surgery (SPSS). In SPSS, the fixation and coordinated movement of a camera held by mechanical devices provides fixed and stable operative images that are under the control of the operator. Therefore, SPSS primarily benefits from the provision of the operator’s eye-to-hand coordination. Because SPSS is an intuitive modification of SPLS, the indications for SPSS are the same as those for SPLS. Though SPSS necessitates more actions than the surgery with a human assistant, these difficulties seem to be easily overcome by the greater provision of static operative images and the need for less lens cleaning and repositioning of the camera. When the operation is expected to be difficult and demanding, the SPSS process could be assisted by the addition of another instrument holder besides the camera holder. PMID:25914453
Cognitive Spare Capacity as an Index of Listening Effort.
Rudner, Mary
2016-01-01
Everyday listening may be experienced as effortful, especially by individuals with hearing loss. This may be due to internal factors, such as cognitive load, and external factors, such as noise. Even when speech is audible, internal and external factors may combine to reduce cognitive spare capacity, or the ability to engage in cognitive processing of spoken information. A better understanding of cognitive spare capacity and how it can be optimally allocated may guide new approaches to rehabilitation and ultimately improve outcomes. This article presents results of three tests of cognitive spare capacity:1. Sentence-final Word Identification and Recall (SWIR) test2. Cognitive Spare Capacity Test (CSCT)3. Auditory Inference Span Test (AIST)Results show that noise reduces cognitive spare capacity even when speech intelligibility is retained. In addition, SWIR results show that hearing aid signal processing can increase cognitive spare capacity, and CSCT and AIST results show that increasing load reduces cognitive spare capacity. Correlational evidence suggests that while the effect of noise on cognitive spare capacity is related to working memory capacity, the effect of load is related to executive function. Future studies should continue to investigate how hearing aid signal processing can mitigate the effect of load on cognitive spare capacity, and whether such effects can be enhanced by developing executive skills through training. The mechanisms modulating cognitive spare capacity should be investigated by studying their neural correlates, and tests of cognitive spare capacity should be developed for clinical use in conjunction with developing new approaches to rehabilitation.
Visual Outcomes of Macular Hole Surgery.
Khaqan, Hussain Ahmad; Lubna; Jameel, Farrukh; Muhammad
2016-10-01
To determine the mean visual improvement after internal limiting membrane (ILM) peeling assisted with brilliant blue staining of ILM in macular hole, and stratify the mean visual improvement in different stages of macular hole. Quasi-experimental study. Eye outpatient department (OPD), Lahore General Hospital, Lahore from October 2013 to December 2014. Patients with macular hole underwent measurement of best corrected visual acuity (BCVA) and fundus examination with indirect slit lamp biomicroscopy before surgery. The diagnosis of all patients was confirmed on optical coherence tomography. All patients had 23G trans-conjunctival three ports pars plana vitrectomy, ILM peeling, and endotamponade of SF6. The mean visual improvement of different stages of macular hole was noted. Paired t-test was applied. There were 30 patients, 15 males and 15 females (50%). The mean age was 62 ±10.95 years. They presented with low mean preoperative visual acuity (VA) of 0.96 ±0.11 logMar. The mean postoperative VAwas 0.63 ±0.24 logMar. The mean visual increase was 0.33 ±0.22 logMar (p < 0.001). In patients with stage 2 macular hole, mean visual increase was 0.35 ±0.20 logMar (p < 0.001). In patients with stage 3 macular hole, mean visual increase was 0.44 ±0.21 logMar (p < 0.001), and in patients with stage 4 macular hole it was 0.13 ± 0.1 logMar (p = 0.004). ILM peeling assisted with brilliant blue is a promising surgery for those patients who have decreased vision due to macular hole, in 2 - 4 stages of macular hole.
Wallsh, Josh O; Gallemore, Ron P; Taban, Mehran; Hu, Charles; Sharareh, Behnam
2013-01-01
To assess the safety and efficacy of a modified technique for pars plana placement of the Ahmed valve in combination with pars plana vitrectomy in the treatment of glaucoma associated with posterior segment disease. Thirty-nine eyes with glaucoma associated with posterior segment disease underwent pars plana vitrectomy combined with Ahmed valve placement. All valves were placed in the pars plana using a modified technique, without the pars plana clip, and using a scleral patch graft. The 24 eyes diagnosed with neovascular glaucoma had an improvement in intraocular pressure from 37.6 mmHg to 13.8 mmHg and best-corrected visual acuity from 2.13 logarithm of minimum angle of resolution to 1.40 logarithm of minimum angle of resolution. Fifteen eyes diagnosed with steroid-induced glaucoma had an improvement in intraocular pressure from 27.9 mmHg to 14.1 mmHg and best-corrected visual acuity from 1.38 logarithm of minimum angle of resolution to 1.13 logarithm of minimum angle of resolution. Complications included four cases of cystic bleb formation and one case of choroidal detachment and explantation for hypotony. Ahmed valve placement through the pars plana during vitrectomy is an effective option for managing complex cases of glaucoma without the use of the pars plana clip.
Early vitrectomy effective for Norrie disease.
Walsh, Mark K; Drenser, Kimberly A; Capone, Antonio; Trese, Michael T
2010-04-01
To review our experience with Norrie disease to determine if early vitrectomy abrogates the natural history of this rare disease; namely, bilateral no light perception visual acuity and phthisis bulbi. We retrospectively reviewed the medical records of all patients seen in our tertiary care pediatric retinal clinical practice from 1988 through 2008 with a potential diagnosis of Norrie disease. Inclusion required not only clinical findings consistent with Norrie disease but also genetics and/or a family history consistent with Norrie disease. Medical record review revealed 14 boys with clinically diagnosed Norrie disease and either Norrie disease gene (NDP) mutations noted on genetic testing (13 patients) and/or a clear family history consistent with Norrie disease (4 patients). All 14 boys with definite Norrie disease had vitrectomy with or without lensectomy in at least 1 eye prior to 12 months of age. Of the 14 boys with definite Norrie disease, 7 maintained at least light perception visual acuity in 1 eye and 3 had no light perception visual acuity bilaterally; visual acuity data were not available for 4 patients. Only 2 of 24 (8%) eyes became phthisical. Historically, no treatment has been offered to mitigate the dismal natural history of Norrie disease. We recommend consideration of early vitrectomy in Norrie disease.
Nam, Ki Yup; Kim, Jung Yeul
2015-05-01
To investigate the difference in the occurrence of postoperative epiretinal membranes (ERMs) in vitrectomy for rhegmatogenous retinal detachment with and without peeling of the internal limiting membrane (ILM). The medical records of the 135 patients, who underwent vitrectomy for primary rhegmatogenous retinal detachment from November 2007 to August 2011, were analyzed retrospectively. Of the subjects, 70 patients underwent ILM peeling during the surgery and 65 did not. The best-corrected visual acuity, fundus photograph, and optical coherence tomography were collected 3, 6, and 12 months postoperatively. The relationship between ILM peeling and the preoperative findings of rhegmatogenous retinal detachment and development of a postoperative ERM was analyzed. No ERM occurred in the ILM peeling group, whereas an ERM occurred in 14 of 65 patients who underwent vitrectomy without ILM peeling (21.5%). This difference was significant (P < 0.001). The occurrence of a postoperative ERM was not significantly correlated with other preoperative factors. In the macular-on group, the overall mean best-corrected visual acuity was better in the ILM peeling group and was significantly higher 12 months postoperatively (P = 0.03). Internal limiting membrane peeling seems to prevent the occurrence of a postoperative ERM in patients with primary rhegmatogenous retinal detachment.
Michalewska, Zofia; Nawrocki, Jerzy
2018-04-30
To describe morphology of retinal and choroidal vessels in swept-source optical coherence tomography angiography before and after vitrectomy with the temporal inverted internal limiting membrane (ILM) flap technique for full-thickness macular holes. Prospective, observational study of 36 eyes of 33 patients with full-thickness macular holes swept-source optical coherence tomography angiography was performed in patients before and 1 month after vitrectomy. Vitrectomy with the temporal inverted ILM flap technique was performed. In this method, ILM is peeled only at one side of the fovea. An ILM flap is created to cover the macular hole. Comparison of retina vasculature in the areas of ILM peeling vs. no ILM peeling at 1 and 3 months after successful vitrectomy was performed. The study demonstrated lower density of vessels in the deep retinal plexus in the area where ILM was peeled as compared to the rest of the fovea. Visual acuity and central retinal thickness 1 month after surgery correlates with fovea avascular zone diameter in deep retinal layers at the same time point (P = 0.001). This study confirmed that ILM peeling might alter blood flow in deep retinal vessels below the peeling area in the early postoperative period. The area of the fovea avascular zone corresponds to functional results at the same time point.
Three-dimensional liquid flattened Luneburg lens with ultra-wide viewing angle and frequency band
NASA Astrophysics Data System (ADS)
Wu, Lingling; Tian, Xiaoyong; Yin, Ming; Li, Dichen; Tang, Yiping
2013-08-01
Traditional Luneburg lens is a dielectric spherical antenna. It can focus the incoming collimated electromagnetic waves on its spherical surface, which causes the incompatibility with the planar feeding and receiving devices. Furthermore, the difficulties in the fabrication process also limited its applications. In this paper, a three-dimensional flattened Luneburg lens with a field-of-view angle up to 180° has been realized based on a liquid medium approach and a 3D-printing process. The fabricated three-dimensional lens showed a broadband transmission characteristic from 12.4 GHz to 18 GHz. The performance of the proposed lens was demonstrated by simulation and experimental results.
Ka-Band Waveguide Three-Way Serial Combiner for MMIC Amplifiers
NASA Technical Reports Server (NTRS)
Wintucky, Edwin G.; Freeman, Jon C.; Chevalier, Christine T.
2012-01-01
In this innovation, the three-way combiner consists internally of two branch-line hybrids that are connected in series by a short length of waveguide. Each branch-line hybrid is designed to combine input signals that are in phase with an amplitude ratio of two. The combiner is constructed in an E-plane split-block arrangement and is precision machined from blocks of aluminum with standard WR-28 waveguide ports. The port impedances of the combiner are matched to that of a standard WR-28 waveguide. The component parts include the power combiner and the MMIC (monolithic microwave integrated circuit) power amplifiers (PAs). The three-way series power combiner is a six-port device. For basic operation, power that enters ports 3, 5, and 6 is combined in phase and appears at port 1. Ports 2 and 4 are isolated ports. The application of the three-way combiner for combining three PAs with unequal output powers was demonstrated. NASA requires narrow-band solid-state power amplifiers (SSPAs) at Ka-band frequencies with output power in the range of 3 to 5 W for radio or gravity science experiments. In addition, NASA also requires wideband, high-efficiency SSPAs at Ka-band frequencies with output power in the range of 5 to 15 W for high-data-rate communications from deep space to Earth. The three-way power combiner is designed to operate over the frequency band of 31.8 to 32.3 GHz, which is NASA s deep-space frequency band.
Thoracoscopic enucleation of a large esophageal leiomyoma using a three thoracic ports technique.
Akaraviputh, Thawatchai; Chinswangwatanakul, Vitoon; Swangsri, Jirawat; Lohsiriwat, Varut
2006-10-04
Video assisted thoracoscopic resection of an esophageal leiomyoma offers distinct advantages over an open approach. Many papers have described various techniques of thoracoscopic resection. We describe a 32-year old man who presented with intermittent dysphagia. Imaging studies showed a large esophageal leiomyoma. He underwent thoracoscopic enucleation using a three thoracic-ports technique. Thoracoscopic enucleation can be technically performed using a three thoracic-ports technique.
Optimal management of idiopathic macular holes
Madi, Haifa A; Masri, Ibrahim; Steel, David H
2016-01-01
This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use. PMID:26834454
Optimal management of idiopathic macular holes.
Madi, Haifa A; Masri, Ibrahim; Steel, David H
2016-01-01
This review evaluates the current surgical options for the management of idiopathic macular holes (IMHs), including vitrectomy, ocriplasmin (OCP), and expansile gas use, and discusses key background information to inform the choice of treatment. An evidence-based approach to selecting the best treatment option for the individual patient based on IMH characteristics and patient-specific factors is suggested. For holes without vitreomacular attachment (VMA), vitrectomy is the only option with three key surgical variables: whether to peel the inner limiting membrane (ILM), the type of tamponade agent to be used, and the requirement for postoperative face-down posturing. There is a general consensus that ILM peeling improves primary anatomical hole closure rate; however, in small holes (<250 µm), it is uncertain whether peeling is always required. It has been increasingly recognized that long-acting gas and face-down positioning are not always necessary in patients with small- and medium-sized holes, but large (>400 µm) and chronic holes (>1-year history) are usually treated with long-acting gas and posturing. Several studies on posturing and gas choice were carried out in combination with ILM peeling, which may also influence the gas and posturing requirement. Combined phacovitrectomy appears to offer more rapid visual recovery without affecting the long-term outcomes of vitrectomy for IMH. OCP is licensed for use in patients with small- or medium-sized holes and VMA. A greater success rate in using OCP has been reported in smaller holes, but further predictive factors for its success are needed to refine its use. It is important to counsel patients realistically regarding the rates of success with intravitreal OCP and its potential complications. Expansile gas can be considered as a further option in small holes with VMA; however, larger studies are required to provide guidance on its use.
Bikbov, M M; Fayzrakhmanov, R R; Kalanov, M R
2018-01-01
To compare morpho-functional parameters of retina during vitrectomy with and without internal limiting membrane (ILM) peeling in patients with proliferative diabetic retinopathy. The study included 55 patients (55 eyes) that had underwent vitreoretinal surgery in the setting of antivasoproliferative therapy for proliferative diabetic retinopathy. Patients of the 1 st group (n=27) underwent vitrectomy with silicone tamponade, 2 nd group (n=28) received similar treatment with the addition of ILM peeling. Three months after the treatment, all patients had silicone oil removed. Best Corrected Visual Acuity before treatment was 0.06±0.02 in both groups; after the treatment it improved to 0.1±0.05 (p<0.05) in the 1 st group and to 0.25±0.05 (p 1-2 <0.05) in the 2 nd group. Thickness of the 'nerve fiber layer - internal limiting membrane' in the macular area was 28.67±2.21 µm in both groups before the treatment. By 3-month follow-up its thickness increased to 46.44±2.56 µm (p<0.05) in the 1 st group due to the formation of epiretinal membrane (ERM). In patients of the 2 nd group 'nerve fiber layer' area thickness amounted to 28.41±1.88 µm (p 1-2 <0.05) and ERM could not be identified in any of them. ILM peeling during vitrectomy with following silicone oil tamponade eliminates the risk of ERM formation in patients with proliferative diabetic retinopathy in the follow-up period of up to 6-month and results in better morpho-functional parameters in comparison with patients who received similar treatment but without peeling.
Three-dimensional magnetic resonance imaging of the phakic crystalline lens during accommodation.
Sheppard, Amy L; Evans, C John; Singh, Krish D; Wolffsohn, James S; Dunne, Mark C M; Davies, Leon N
2011-06-01
To quantify changes in crystalline lens curvature, thickness, equatorial diameter, surface area, and volume during accommodation using a novel two-dimensional magnetic resonance imaging (MRI) paradigm to generate a complete three-dimensional crystalline lens surface model. Nineteen volunteers, aged 19 to 30 years, were recruited. T(2)-weighted MRIs, optimized to show fluid-filled chambers of the eye, were acquired using an eight-channel radio frequency head coil. Twenty-four oblique-axial slices of 0.8 mm thickness, with no interslice gaps, were acquired to visualize the crystalline lens. Three Maltese cross-type accommodative stimuli (at 0.17, 4.0, and 8.0 D) were presented randomly to the subjects in the MRI to examine lenticular changes with accommodation. MRIs were analyzed to generate a three-dimensional surface model. During accommodation, mean crystalline lens thickness increased (F = 33.39, P < 0.001), whereas lens equatorial diameter (F = 24.00, P < 0.001) and surface radii both decreased (anterior surface, F = 21.78, P < 0.001; posterior surface, F = 13.81, P < 0.001). Over the same stimulus range, mean crystalline lens surface area decreased (F = 7.04, P < 0.005) with a corresponding increase in lens volume (F = 6.06, P = 0.005). These biometric changes represent a 1.82% decrease and 2.30% increase in crystalline lens surface area and volume, respectively. CONCLUSIONS; The results indicate that the capsular bag undergoes elastic deformation during accommodation, causing reduced surface area, and the observed volumetric changes oppose the theory that the lens is incompressible.
Ultrathin zoom lens system based on liquid lenses
NASA Astrophysics Data System (ADS)
Li, Lei; Liu, Chao; Wang, Qiong-Hua
2015-07-01
In this paper, we propose an ultrathin zoom lens system based on liquid lenses. The proposed system consists of an annular folded lens and three electrowetting liquid lenses. The annular folded lens has several concentric surfaces. The annular folded lens is used to get the main power and correct aberrations. The three liquid lenses are used to change the focal length and correct aberration. An analysis of the proposed system is presented along with the design, fabrication, and testing of a prototype. All the elements in the proposed system are very thin, so the system is an ultrathin zoom lens system, which has potential application as lightweight, thin, high-quality imagers for aerospace, consumer, and military applications.
The effect of handpiece spray patterns on cutting efficiency.
Siegel, Sharon C; von Fraunhofer, J Anthony
2002-02-01
High-speed handpieces' spray ports direct coolant at the cutting interface. The authors evaluated the effect of the number of ports and their positions on cutting rates, or CRs. The authors performed cutting studies on a machinable ceramic block using an established testing regimen. One-port, three-port and four-port handpieces from one manufacturer were operated at maximum torque and rotation speed under a water flow of 25 milliliters per minute. The authors made 6-millimeter long edge and groove cuts in 13-mm cross-section blocks using six medium-grit diamond burs for each handpiece. Each bur cut a total of 78 mm. The authors determined CR as the time to transect the block and analyzed the data by two-way analysis of variance with post hoc Scheffé tests. CRs varied by the type of cut and the number of spray ports. No differences were found in CRs for the three handpieces during edge cutting. The one-port handpiece cut significantly slower (P < .001) than did the three- and four-port handpieces during groove cutting. The data indicate that the number of handpiece spray ports, and their positioning relative to the bur affect water supply to the cutting interface and, consequently, the CR under these study conditions. Optimal cutting efficiency requires good coolant access, especially within restricted areas. A multiple-port handpiece may be advantageous when preparing the interproximal region for a crown or a proximal box, owing to the better water spray pattern. Dentists should consider the influence of the number of spray ports when selecting handpieces for cutting procedures.
46 CFR 169.529 - Description of lifeboat equipment.
Code of Federal Regulations, 2010 CFR
2010-10-01
... § 94.20-15(j) of this chapter. Three spare cells (or one 3-cell battery) and two spare bulbs, stowed in... painter must be attached to the stem. (z) Plug. The automatic drain required in the lifeboat must be...
46 CFR 169.529 - Description of lifeboat equipment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... § 94.20-15(j) of this chapter. Three spare cells (or one 3-cell battery) and two spare bulbs, stowed in... painter must be attached to the stem. (z) Plug. The automatic drain required in the lifeboat must be...
46 CFR 169.529 - Description of lifeboat equipment.
Code of Federal Regulations, 2014 CFR
2014-10-01
... § 94.20-15(j) of this chapter. Three spare cells (or one 3-cell battery) and two spare bulbs, stowed in... painter must be attached to the stem. (z) Plug. The automatic drain required in the lifeboat must be...
46 CFR 169.529 - Description of lifeboat equipment.
Code of Federal Regulations, 2011 CFR
2011-10-01
... § 94.20-15(j) of this chapter. Three spare cells (or one 3-cell battery) and two spare bulbs, stowed in... painter must be attached to the stem. (z) Plug. The automatic drain required in the lifeboat must be...
46 CFR 169.529 - Description of lifeboat equipment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... § 94.20-15(j) of this chapter. Three spare cells (or one 3-cell battery) and two spare bulbs, stowed in... painter must be attached to the stem. (z) Plug. The automatic drain required in the lifeboat must be...
Peng, Jie; Zhang, Qi; Jin, Hai-Ying; Lu, Wu-Yi; Zhao, Pei-Quan
2016-01-01
To compare the results of non-mydriatic ultra-wide field imaging system, mydriatic slit-lamp lens (Volk +90 D) and mydriatic Goldmann three-mirror contact lens examinations in screening fundus lesions among patients after cataract surgery. Non-mydriatic images were obtained with an Optomap panoramic 200Tx (Optomap 200Tx) 3d after surgery and graded by a blinded ophthalmologist. A mydriatic slit-lamp lens examination was performed by another blinded retinal specialist on the same day. A third blinded retinal specialist examined patients two weeks after surgery using a Goldmann three-mirror contact lens. In total, 160 patients (184 eyes) were examined, and 66, 69, and 75 cases of retinal lesion(s) were identified using the Optomap 200Tx, slit-lamp lens, and Goldmann three-mirror contact lens, respectively. In 13 cases, fundus changes were sight-threatening. The results obtained by Optomap 200Tx examination and by mydriatic slit-lamp lens examination have good consistency (P=0.375, Kappa=0.942). The mydriatic Goldmann three-mirror lens examination revealed more fundus lesions but are consistent with Optomap 200Tx (P=0.004, Kappa=0.897) and mydriatic slit-lamp lens examination (P=0.031, Kappa=0.932). Early post-operative fundus screening in cataract patients is extremely important and necessary to prevent further vision loss. Wide-field imaging is a feasible and convenient tool for fundus examination that can be used as a primary screening method among patients after cataract surgery.
Pound--Drever--Hall error signals for the length control of three-port grating coupled cavities
NASA Astrophysics Data System (ADS)
Britzger, Michael; Friedrich, Daniel; Kroker, Stefanie; Brückner, Frank; Burmeister, Oliver; Kley, Ernst-Bernhard; Tünnermann, Andreas; Danzmann, Karsten; Schnabel, Roman
2011-08-01
Gratings enable light coupling into an optical cavity without transmission through any substrate. This concept reduces light absorption and substrate heating and was suggested for light coupling into the arm cavities of future gravitational wave detectors. One particularly interesting approach is based on all-reflective gratings with low diffraction efficiencies and three diffraction orders (three ports). However, it was discovered that, generally, three-port grating coupled cavities show an asymmetric resonance profile that results in asymmetric and low quality Pound--Drever--Hall error signals for cavity length control. We experimentally demonstrate that this problem is solved by the detection of light at both reflection ports of the cavity and the postprocessing of the two demodulated electronic signals.
Characteristics of Endophthalmitis after Cataract Surgery in the United States Medicare Population.
Gower, Emily W; Keay, Lisa J; Stare, Dianne E; Arora, Pallavi; Cassard, Sandra D; Behrens, Ashley; Tielsch, James M; Schein, Oliver D
2015-08-01
Endophthalmitis is a rare but sight-threatening infection after cataract surgery. Roughly one third of eyes remain blind after treatment. We report United States population-based data on microbiological investigations and treatment patterns plus risk factors for poor outcomes. Retrospective cohort study. Medicare beneficiaries from 5 states in whom endophthalmitis developed within 6 weeks after cataract surgery in 2003 and 2004. We identified endophthalmitis cases occurring after cataract surgery using Medicare billing claims. We contacted treating physicians and requested they complete a questionnaire on clinical and microbiological data and submit relevant medical records. Two independent observers reviewed materials to confirm that cases met a standardized definition. Positive culture results, vitrectomy status, microbiology spectrum, and final visual acuity. In total, 615 cases met our case definition. Initial visual acuity was counting fingers or worse for 72%. Among 502 cases with known culture results, 291 (58%) had culture positive results. Twelve percent had positive results for streptococci. More than 99% of cases were treated with intravitreal vancomycin. Vitrectomy was performed in 279 cases (45%), including 201 cases with initial acuity better than light perception. Rates of vitrectomy varied across states, with California having the highest rate and Michigan having the lowest (56% and 19% of cases, respectively). Overall, 43% of individuals achieved visual acuity of 20/40 or better. Poor initial acuity (adjusted odds ratio [OR], 1.08; 95% confidence interval [CI], 1.04-1.12 per 0.10 logarithm of the minimum angle of resolution units), older age at diagnosis (OR, 1.22; 95% CI, 1.03-1.45 per 5-year increase), and more virulent organisms were important predictors of poor final visual acuity. Cases with streptococci infection were 10 times more likely to have poor final acuity than coagulase-negative staphylococci cases (adjusted OR, 11.28; 95% CI, 3.63-35.03). Vitrectomy was not predictive of final visual acuity (adjusted OR, 1.26; 95% CI, 0.78-2.04). Population-based data on the microbiology of acute postoperative endophthalmitis in the United States after cataract surgery are consistent with prior reports. Vitrectomy usage is higher than that recommended from the Endophthalmitis Vitrectomy Study, with no evidence of increased benefit. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
Using Spare Logic Resources To Create Dynamic Test Points
NASA Technical Reports Server (NTRS)
Katz, Richard; Kleyner, Igor
2011-01-01
A technique has been devised to enable creation of a dynamic set of test points in an embedded digital electronic system. As a result, electronics contained in an application specific circuit [e.g., gate array, field programmable gate array (FPGA)] can be internally probed, even when contained in a closed housing during all phases of test. In the present technique, the test points are not fixed and limited to a small number; the number of test points can vastly exceed the number of buffers or pins, resulting in a compact footprint. Test points are selected by means of spare logic resources within the ASIC(s) and/or FPGA(s). A register is programmed with a command, which is used to select the signals that are sent off-chip and out of the housing for monitoring by test engineers and external test equipment. The register can be commanded by any suitable means: for example, it could be commanded through a command port that would normally be used in the operation of the system. In the original application of the technique, commanding of the register is performed via a MIL-STD-1553B communication subsystem.
Cornea and ocular lens visualized with three-dimensional confocal microscopy
NASA Astrophysics Data System (ADS)
Masters, Barry R.
1992-08-01
This paper demonstrates the advantages of three-dimensional reconstruction of the cornea and the ocular crystalline lens by confocal microscopy and volume rendering computer techniques. The advantages of noninvasive observation of ocular structures in living, unstained, unfixed tissue include the following: the tissue is in a natural living state without the artifacts of fixation, mechanical sectioning, and staining; the three-dimensional structure can be observed from any view point and quantitatively analyzed; the dynamics of morphological changes can be studied; and the use of confocal microscopic observation results in a reduction of the number of animals required for ocular morphometric studies. The main advantage is that the dynamic morphology of ocular structures can be investigated in living ocular tissue. A laser scanning confocal microscope was used in the reflected light mode to obtain the two- dimensional images from the cornea and the ocular lens of a freshly enucleated rabbit eye. The light source was an argon ion laser with 488 nm wavelength. The microscope objective was a Leitz 25X, NA 0.6 water immersion lens. The 400 micron thick cornea was optically sectioned into 133, three micron sections. The semi-transparent cornea and the in-situ ocular lens was visualized as high resolution, high contrast two-dimensional images. The under sampling resulted in a three-dimensional visualization rendering in which the corneal thickness (z-axis) is compressed. The structures observed in the cornea include: superficial epithelial cells and their nuclei, basal epithelial cells and their `beaded' cell borders, basal lamina, nerve plexus, nerve fibers, free nerve endings in the basal epithelial cells, nuclei of stromal keratocytes, and endothelial cells. The structures observed in the in-situ ocular lens include: lens capsule, lens epithelial cells, and individual lens fibers.
Vitreous floaters: Etiology, diagnostics, and management.
Milston, Rebecca; Madigan, Michele C; Sebag, J
2016-01-01
Vitreous is a hydrated extracellular matrix comprised primarily of water, collagens, and hyaluronan organized into a homogeneously transparent gel. Gel liquefaction results from molecular alterations with dissociation of collagen from hyaluronan and aggregation of collagen fibrils forming fibers that cause light scattering and hence symptomatic floaters, especially in myopia. With aging, gel liquefaction and weakened vitreoretinal adhesion result in posterior vitreous detachment, the most common cause of primary symptomatic floaters arising from the dense collagen matrix of the posterior vitreous cortex. Recent studies indicate that symptomatic floaters are not only more prevalent, but also have a negative impact on the quality of life that is greater than previously appreciated. We review the literature concerning management of symptomatic vitreous floaters, currently either with observation, vitrectomy, or Nd:YAG laser. Published evidence is consistent with a low-risk profile and excellent success rate for floater vitrectomy, particularly with sutureless small gauge instruments and a limited core vitrectomy without PVD induction. Nd:YAG laser treatment of floaters, reported less commonly, claims resolution of floaters ranging between 0% and 100%; however, both peer-reviewed literature and assertions on web-based nonpeer-reviewed laser vitreolysis sites remain to be substantiated, and at present only vitrectomy has proven value. Prospective studies using objective, quantitative outcome measures are required to assess the relative efficacy and safety of these two procedures as well as new therapies such as pharmacologic vitreolysis. Copyright © 2016 Elsevier Inc. All rights reserved.
Lin, Jijian; Su, Zhitao; Huang, Xiaodan; Ji, Xian; Yao, Ke
2016-11-01
To evaluate the safety and efficacy of posterior continuous curvilinear capsulorhexis through the pars plana and 23-gauge vitrectomy in surgical management of dense posterior capsule opacification and vitreous floaters. Fifteen pseudophakic eyes of 15 patients with dense posterior capsule opacification and vitreous floaters between September 2012 and June 2014 were included; after vitrectomy, posterior continuous curvilinear capsulorhexis through the pars plana was performed. Data were collected, including baseline preoperative characteristics, postoperative outcomes, complications, and a modified quality-of-life survey that patients completed. No intraoperative or postoperative complications were encountered in any of the 15 cases. Mean Snellen best-corrected visual acuity was 20/250 preoperatively and improved to 20/32 postoperatively (P < 0.001). All patients showed normal intraocular pressure 7 days after the procedure. The mean overall corneal endothelial cell loss at postoperative Month 3 was 1.2%. Approximately 80% of the patients had no complaint of vitreous floaters after the procedure. Except for 1 patient (7%) diagnosed with age-related macular degeneration, the rest of the patients (93%) were satisfied with the procedure and would recommend it to friends with dense posterior capsule opacification and vitreous floaters. Posterior continuous curvilinear capsulorhexis through the pars plana combined with 23-gauge vitrectomy may be used to remove dense posterior capsule opacification and vitreous floaters in pseudophakic eyes.
Vitrectomy for the diagnosis and management of uveitis of unknown cause.
Margolis, Ron; Brasil, Oswaldo F M; Lowder, Careen Y; Singh, Rishi P; Kaiser, Peter K; Smith, Scott D; Perez, Victor L; Sonnie, Christine; Sears, Jonathan E
2007-10-01
To determine the diagnostic yield of tests commonly used for vitreous fluid analysis in eyes with suspected intraocular infection or malignancy. Noncomparative interventional case series. Forty-four consecutive patients (45 eyes) treated from 1998 through 2006 with posterior segment inflammation who underwent pars plana vitrectomy for diagnostic purposes. Vitreous specimens obtained via pars plana vitrectomy were analyzed by microbiologic culture, cytologic analysis, and flow cytometry. Diagnostic yield and sensitivity of each test performed on vitreous specimens and visual outcomes of eyes that underwent diagnostic vitrectomy (DVx). Preoperative diagnoses were infection in 15 eyes and malignancy in 30 eyes. Overall, vitreous analysis identified a specific cause in 9 (20%) of 45 eyes. The overall sensitivity of DVx was 63.6%. The sensitivities of individual tests were: culture, 50%; cytologic analysis, 66.7%; and flow cytometry, 83.3%. The yields of diagnostic tests were: culture, 5.7%; cytologic analysis, 14.3%; and flow cytometry, 20.6%. Final diagnoses were infection in 6 eyes, malignancy in 9 eyes, and idiopathic in 30 eyes. Mean visual acuity improved significantly in the first 6 months after DVx. Visual acuity improved in 60% of eyes, with 37.8% of eyes improving by 3 lines or more. Analysis of vitreous fluid by widely available tests is useful in identifying intraocular infection or malignancy. Most patients experienced a substantial improvement in vision.
Wollanke, B; Gerhards, H; Brem, S; Kopp, H; Meyer, P
1998-04-01
Between February 1993 and July 1997, 150 horses suffering from recurrent uveitis were subjected to parsplana vitrectomy. In these horses, antibody titers to Leptospira serovars were determined in serum samples and in samples from diluted vitreous collected during vitrectomy. Although the vitreous samples were diluted with 250 ml of balanced salt solution, in 86 of the 150 vitreous samples (= 57%) the antibody titers were higher than in the serum samples. Additionally, serum samples from 77 horses suffering from ERU, but which were not subjected to vitrectomy, and serum samples from 97 horses with clinically normal eyes were analyzed for antibodies to Leptospira serovars. Among the 227 horses with ERU (150 treated surgically, 77 treated conservatively) 50 horses (50 of 227 = 22%) had serum antibody titers to Leptospira serovars of > or = 1:800. Among the 97 horses with clinically normal eyes, 24 horses (24 of 97 = 25%) had serum antibody titers to Leptospira serovars of > or = 1:800. In undiluted vitreous samples from 20 horses with clinically normal eyes, no antibody titers to Leptospira serovars could be detected. Among the 150 horses with ERU, 90 animals (90 of 150 = 60%) had antibody titers of > or = 1:100 in the diluted vitreous samples, the difference being highly significant (p < 0.001). The findings are discussed in relation to the etiology of recurrent uveitis in horses.
THE ADVANTAGES OF FEMTOSECOND LASER-ASSISTED CATARACT SURGERY
Gavris, M Monica; Belicioiu, Roxana; Olteanu, Ioana; Horge, Ioan
2015-01-01
Purpose: To present the advantages of performing femtosecond laser-assisted (Alcon-LenSx Inc.) cataract surgery. Methods: Cataract surgery was performed with the LenSx femtosecond laser (Alcon-LenSx Inc.) in 50 eyes of 50 patients. The laser was programmed to perform a 4,9-4,5 mm capsulorhexis, a 2,3 mm main corneal incision, two 1,3 mm side-port incisions and either a hybrid-pattern or a cylinder-pattern fragmentation of the nucleus. The evaluated parameters were the capsulotomy, the corneal wounds and the nucleus fragmentation. Phacoemulsification of the nucleus and aspiration of the cortex were performed with the Alcon Centurion Vision System and monofocal, toric and multifocal IOLs were successfully implanted. Results: A continuous, central, curvilinear capsulorhexis was performed in 48 cases, 96% (free-floating capsulotomy). In 2 cases, micro-adhesions were reported and detached with the Utrata forceps. Femtolaser capsulotomy resulted in a complete overlap of the anterior capsule over the IOL optics in all cases. Horizontal decentration was found in 2 cases, 4% and vertical decentration in 1 case, 2%. The main corneal incision was self-sealing in 49 cases, 98%. Sutures were used in 1 case, 2%. The hybrid pattern of nucleus fragmentation was used in 42 cases, 84% and the cylindrical pattern in 8 cases, 16%. The fragmentation was incomplete in one case of white cataract and in one case of traumatic cataract. Conclusions: The main advantages of femtolaser cataract surgery are standardized corneal incisions, perfectly centered, round capsulorhexis, and lens nucleus fragmentation even in eyes with hard cataracts. The laser precision is due to the real time OCT software programs, which cover the whole anterior segment, up to the posterior lens capsule. PMID:27373114
Organizing for the Future Requires the Non-Aristotelian Lens of a Dragonfly.
ERIC Educational Resources Information Center
Collins, Marla Del
To organize for the future requires non-Aristotelian thinking...a multifaceted wide-angle lens revealing hidden information. A multifaceted lens includes at least three general systems of evaluation, all of which promote complex thinking. The three systems are general semantics, postmodern feminist philosophy, and the unifying principle of…
STS-56 Earth observation of the northeastern Nile Delta
1993-04-17
STS-56 Earth observation of the northeastern Nile Delta was photographed from the Earth-orbiting Discovery, Orbiter Vehicle (OV) 103. The branch of the Nile featured in the frame is Daimietta. The Suez Canal marks the boundary of the Nile Delta agriculture and the Sinai Desert to the right. Lake Masada, the dark waterlogged area to the west (left) of Port Said is becoming more saline as the Aswan Dam has reduced sediment downstream. This sediment reduction, according to NASA scientists studying the STS-56 photography, has resulted in increased coastal erosion and the intrusion of a salt-water lens to the ground water, particularly in the northeastern portions of the delta. Center pivot irrigation fields are located along either side of the Ramses Canal, which connects the Daimietta Nile with Great Bitter Lake. This canal has been re-dug three or four times in the past 3,000 years. Historians note that the canal's most famous use was as the departure point of the fleet of Pharaoh Necho. The fleet circumnavigated Africa clockwise from the head of the Red Sea to the Mediterranean coast of the Nile (probably the Rosetta Nile) in a three-year voyage circa 660 BC.
Zhang, Zhaotian; Zhang, Shaochong; Jiang, Xintong; Qiu, Suo; Wei, Yantao
2016-01-04
Glaucoma combined with an extremely shallow anterior chamber and cataracts remains as a complex condition to deal with. And the emergence of microincision vitrectomy surgery (MIVS) system may provide an ideal option for the treatment of that. We report a clinical study of surgical outcomes of 23-gauge transconjunctival pars plana vitrectomy (PPV) combined with lensectomy in the treatment of glaucomatous eyes with extremely shallow anterior chamber and cataract. Prospective, nonrandomized and noncomparative case series study. Consecutive patients with secondary glaucoma, extremely shallow anterior chamber and cataract were recruited to have combined surgeries of 23-gauge transconjunctival pars plana vitrectomy and lensectomy. The main outcomes were best corrected visual acuity (BCVA), intraocular pressure (IOP), anterior chamber depth (ACD), number of anti-glaucoma medications and surgery-associated complications. Seventeen consecutive patients with secondary glaucoma, extremely shallow anterior chamber and cataract were recruited. The mean follow-up was 21.2 ± 8.8 months. Postoperatively, there was no significant improvement of BCVA (P = 0.25). The mean intraocular (IOP) decreased significantly from 43.14 ± 6.53 mmHg to 17.29 ± 1.80 mmHg (P < 0.001), and the mean depth of anterior chamber increased significantly from 0.507 ± 0.212 mm to 3.080 ± 0.313 mm (P < 0.001). The mean number of anti-glaucoma medications decreased from 4.1 ± 0.8 to 0.6 ± 0.8 (P < 0.001). No severe vision-threatening intra- or post-operative complications occurred. Glaucoma with an extremely shallow anterior chamber and cataract can be managed well with the combined surgeries of 23-gauge pars plana vitrectomy and lensectomy. The surgical procedure is an effective and safe method to resolve the pupillary block and deepen the anterior chamber.
Abouammoh, Marwan A; Alsulaiman, Sulaiman M; Gupta, Vishali S; Mousa, Ahmed; Hirakata, Akito; Berrocal, Maria H; Chenworth, Megan; Chhablani, Jay; Oshima, Yusuke; AlZamil, Waseem M; Casella, Antonio Marcelo; Papa-Oliva, Gabriela; Banker, Alay S; Arevalo, J Fernando
2016-04-01
To compare the functional and anatomic outcomes of pars plana vitrectomy (PPV) with juxtapapillary laser photocoagulation (JLP) versus vitrectomy without JLP in optic disc pit maculopathy. This was a multicentre, retrospective study of 46 consecutive patients with optic disc pit maculopathy presenting at tertiary eye centres between 1992 and 2012. Indications for surgery included distorted or decreased vision. Surgical intervention included PPV, posterior vitreous detachment, with or without gas tamponade. Twenty-four patients received laser photocoagulation at the temporal edge of the optic disc pit (group A) and 22 patients had no laser (group B). Postoperative best-corrected visual acuity (BCVA) and optical coherence tomography findings were the main outcome measures. Mean follow-up was 44 months (range 12-98 months). BCVA in group A improved significantly from 0.7 logMAR (20/100) preoperatively to 0.5 logMAR (20/60) postoperatively (p=0.017). In group B, BCVA improved from 0.7 logMAR (20/100) preoperatively to 0.4 logMAR (20/40) postoperatively (p=0.014). The difference in final BCVA between groups was not statistically significant (p=0.693). The mean central macular thickness (CMT) in group A improved significantly from 750 μm preoperatively to 309 μm at last follow-up (p<0.0001). The mean CMT in group B improved from 616 μm preoperatively to 291 μm at last follow-up (p=0.028). The difference in final CMT between groups was not statistically significant (p=0.747). PPV with JLP for optic disc pit maculopathy had similar functional and anatomic outcomes compared with vitrectomy without JLP. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
W-band six-port network analyzer for two-port characterization of millimeter wave transistors
NASA Technical Reports Server (NTRS)
Moeller, Karl J.; Schaffner, James H.; Fetterman, Harold R.
1989-01-01
A W-band (75-100 GHz) six-port junction network analyzer was constructed from commercially available descrete waveguide components and was used for the direct two-port S-parameter measurement of active three-terminal devices. A comparison between the six-port and a down-converter-type frequency extender for a conventional network analyzer revealed the superior performance of the six-port. The application of the six-port to characterize a 0.1-micron gate-length HEMT at W-band is described, and representative results are presented.
Three-Dimensional Cataract Crystalline Lens Imaging With Swept-Source Optical Coherence Tomography.
de Castro, Alberto; Benito, Antonio; Manzanera, Silvestre; Mompeán, Juan; Cañizares, Belén; Martínez, David; Marín, Jose María; Grulkowski, Ireneusz; Artal, Pablo
2018-02-01
To image, describe, and characterize different features visible in the crystalline lens of older adults with and without cataract when imaged three-dimensionally with a swept-source optical coherence tomography (SS-OCT) system. We used a new SS-OCT laboratory prototype designed to enhance the visualization of the crystalline lens and imaged the entire anterior segment of both eyes in two groups of participants: patients scheduled to undergo cataract surgery, n = 17, age range 36 to 91 years old, and volunteers without visual complains, n = 14, age range 20 to 81 years old. Pre-cataract surgery patients were also clinically graded according to the Lens Opacification Classification System III. The three-dimensional location and shape of the visible opacities were compared with the clinical grading. Hypo- and hyperreflective features were visible in the lens of all pre-cataract surgery patients and in some of the older adults in the volunteer group. When the clinical examination revealed cortical or subcapsular cataracts, hyperreflective features were visible either in the cortex parallel to the surfaces of the lens or in the posterior pole. Other type of opacities that appeared as hyporeflective localized features were identified in the cortex of the lens. The OCT signal in the nucleus of the crystalline lens correlated with the nuclear cataract clinical grade. A dedicated OCT is a useful tool to study in vivo the subtle opacities in the cataractous crystalline lens, revealing its position and size three-dimensionally. The use of these images allows obtaining more detailed information on the age-related changes leading to cataract.
[Vitrectomy: in search of the ideal vitreous replacement].
Steijns, Daan; Stilma, Jan S
2009-01-01
Pars plana vitrectomy is a form of surgery to remove the vitreous body. It is performed with various eye diseases. Replacement of the vitreous body is necessitated by its removal. After more than 50 years the search for the ideal vitreous replacement has not yet ended. Different materials are used to replace the vitreous body. The advantages, disadvantages and applications of those materials are discussed. The lack of a material to successfully replace the vitreous body is a significant restriction in the treatment vitreoretinal pathologies.
Nazari, Hossein; Modarres-Zadeh, Mehdi; Maleki, Arash
2010-01-01
The vitreoretinal interface is involved in a wide range of vitreoretinal disorders and separation of the posterior vitreous face from the retinal surface is an essential part of vitrectomy surgeries. A diverse range of enzymatic and non-enzymatic agents are being studied as an adjunct before or during vitrectomy to facilitate the induction of posterior vitreous detachment. There is a significant body of knowledge in the literature about different vitreolytic agents under investigation for a variety of pathologies involving the vitreoretinal interface which will be summarized in this review. PMID:22737326
2011-07-08
CAPE CANAVERAL, Fla. -- Liberty Star, one of NASA's solid rocket booster retrieval ships, tows a spent booster from space shuttle Atlantis' final launch, to Port Canaveral in Florida. A Cape Canaveral Port Authority tug sends a spray of water through its cannon as a welcome back to the Port. The shuttle's two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Freedom Star and Liberty Star. The boosters impact the Atlantic about seven minutes after liftoff and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be deserviced and stored, if needed. Atlantis began its final flight at 11:29 a.m. EDT on July 8 to deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts for the International Space Station. Atlantis also delivers the Robotic Refueling Mission experiment that will investigate the potential for robotically refueling existing satellites in orbit to the station. In addition, Atlantis will return with a failed ammonia pump module to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135 is the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett
2011-07-08
CAPE CANAVERAL, Fla. -- Liberty Star, one of NASA's solid rocket booster retrieval ships, tows a spent booster from space shuttle Atlantis' final launch, to Port Canaveral in Florida. A Cape Canaveral Port Authority tug sends a spray of water through its cannon as a welcome back to the Port. The shuttle's two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Freedom Star and Liberty Star. The boosters impact the Atlantic about seven minutes after liftoff and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be deserviced and stored, if needed. Atlantis began its final flight at 11:29 a.m. EDT on July 8 to deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts for the International Space Station. Atlantis also delivers the Robotic Refueling Mission experiment that will investigate the potential for robotically refueling existing satellites in orbit to the station. In addition, Atlantis will return with a failed ammonia pump module to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135 is the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett
2011-07-08
CAPE CANAVERAL, Fla. -- Liberty Star, one of NASA's solid rocket booster retrieval ships, tows a spent booster from space shuttle Atlantis' final launch, to Port Canaveral in Florida. A Cape Canaveral Port Authority tug sends a spray of water through its cannon as a welcome back to the Port. The shuttle's two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Freedom Star and Liberty Star. The boosters impact the Atlantic about seven minutes after liftoff and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be deserviced and stored, if needed. Atlantis began its final flight at 11:29 a.m. EDT on July 8 to deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts for the International Space Station. Atlantis also delivers the Robotic Refueling Mission experiment that will investigate the potential for robotically refueling existing satellites in orbit to the station. In addition, Atlantis will return with a failed ammonia pump module to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135 is the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program. For more information, visit www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett
Kim, Hwi; Hahn, Joonku; Choi, Hee-Jin
2011-04-10
We investigate the viewing angle enhancement of a lenticular three-dimensional (3D) display with a triplet lens array. The theoretical limitations of the viewing angle and view number of the lenticular 3D display with the triplet lens array are analyzed numerically. For this, the genetic-algorithm-based design method of the triplet lens is developed. We show that a lenticular 3D display with viewing angle of 120° and 144 views without interview cross talk can be realized with the use of an optimally designed triplet lens array. © 2011 Optical Society of America
de Castro, Alberto; Ortiz, Sergio; Gambra, Enrique; Siedlecki, Damian; Marcos, Susana
2010-10-11
We present an optimization method to retrieve the gradient index (GRIN) distribution of the in-vitro crystalline lens from optical path difference data extracted from OCT images. Three-dimensional OCT images of the crystalline lens are obtained in two orientations (with the anterior surface up and posterior surface up), allowing to obtain the lens geometry. The GRIN reconstruction method is based on a genetic algorithm that searches for the parameters of a 4-variable GRIN model that best fits the distorted posterior surface of the lens. Computer simulations showed that, for noise of 5 μm in the surface elevations, the GRIN is recovered with an accuracy of 0.003 and 0.010 in the refractive indices of the nucleus and surface of the lens, respectively. The method was applied to retrieve three-dimensionally the GRIN of a porcine crystalline lens in vitro. We found a refractive index ranging from 1.362 in the surface to 1.443 in the nucleus of the lens, an axial exponential decay of the GRIN profile of 2.62 and a meridional exponential decay ranging from 3.56 to 5.18. The effect of GRIN on the aberrations of the lens also studied. The estimated spherical aberration of the measured porcine lens was 2.87 μm assuming a homogenous equivalent refractive index, and the presence of GRIN shifted the spherical aberration toward negative values (-0.97 μm), for a 6-mm pupil.
Peripheral Venous Access Ports: Outcomes Analysis in 109 Patients
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bodner, Leonard J.; Nosher, John L.; Patel, Kaushik M.
Purpose: To perform a retrospective outcomes analysis of central venous catheters with peripheral venous access ports, with comparison to published data.Methods: One hundred and twelve central venous catheters with peripherally placed access ports were placed under sonographic guidance in 109 patients over a 4-year period. Ports were placed for the administration of chemotherapy, hyperalimentation, long-term antibiotic therapy, gamma-globulin therapy, and frequent blood sampling. A vein in the upper arm was accessed in each case and the catheter was passed to the superior vena cava or right atrium. Povidone iodine skin preparation was used in the first 65 port insertions. Amore » combination of Iodophor solution and povidone iodine solution was used in the last 47 port insertions. Forty patients received low-dose (1 mg) warfarin sodium beginning the day after port insertion. Three patients received higher doses of warfarin sodium for preexistent venous thrombosis. Catheter performance and complications were assessed and compared with published data.Results: Access into the basilic or brachial veins was obtained in all cases. Ports remained functional for a total of 28,936 patient days. The port functioned in 50% of patients until completion of therapy, or the patient's expiration. Ports were removed prior to completion of therapy in 18% of patients. Eleven patients (9.9% of ports placed) suffered an infectious complication (0.38 per thousand catheter-days)-in nine, at the port implantation site, in two along the catheter. In all 11 instances the port was removed. Port pocket infection in the early postoperative period occurred in three patients (4.7%) receiving a Betadine prep vs two patients (4.2%) receiving a standard O.R. prep. This difference was not statistically significant (p = 0.9). Venous thrombosis occurred in three patients (6.8%) receiving warfarin sodium and in two patients (3%) not receiving warfarin sodium. This difference was not statistically significant (p = 0.6). Aspiration occlusion occurred in 13 patients (11.7%). Intracatheter urokinase was infused in eight of these patients and successfully restored catheter function in all but two instances. These complication rates are comparable to or better than those reported with chest ports.Conclusion: Peripheral ports for long-term central venous access placed by interventional radiologists in the interventional radiology suite are as safe and as effective as chest ports.« less
In vivo human crystalline lens topography.
Ortiz, Sergio; Pérez-Merino, Pablo; Gambra, Enrique; de Castro, Alberto; Marcos, Susana
2012-10-01
Custom high-resolution high-speed anterior segment spectral domain optical coherence tomography (OCT) was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo. The system was provided with custom algorithms for denoising and segmentation of the images, as well as for fan (scanning) and optical (refraction) distortion correction, to provide fully quantitative images of the anterior and posterior crystalline lens surfaces. The method was tested on an artificial eye with known surfaces geometry and on a human lens in vitro, and demonstrated on three human lenses in vivo. Not correcting for distortion overestimated the anterior lens radius by 25% and the posterior lens radius by more than 65%. In vivo lens surfaces were fitted by biconicoids and Zernike polynomials after distortion correction. The anterior lens radii of curvature ranged from 10.27 to 14.14 mm, and the posterior lens radii of curvature ranged from 6.12 to 7.54 mm. Surface asphericities ranged from -0.04 to -1.96. The lens surfaces were well fitted by quadrics (with variation smaller than 2%, for 5-mm pupils), with low amounts of high order terms. Surface lens astigmatism was significant, with the anterior lens typically showing horizontal astigmatism ([Formula: see text] ranging from -11 to -1 µm) and the posterior lens showing vertical astigmatism ([Formula: see text] ranging from 6 to 10 µm).
In vivo human crystalline lens topography
Ortiz, Sergio; Pérez-Merino, Pablo; Gambra, Enrique; de Castro, Alberto; Marcos, Susana
2012-01-01
Custom high-resolution high-speed anterior segment spectral domain optical coherence tomography (OCT) was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo. The system was provided with custom algorithms for denoising and segmentation of the images, as well as for fan (scanning) and optical (refraction) distortion correction, to provide fully quantitative images of the anterior and posterior crystalline lens surfaces. The method was tested on an artificial eye with known surfaces geometry and on a human lens in vitro, and demonstrated on three human lenses in vivo. Not correcting for distortion overestimated the anterior lens radius by 25% and the posterior lens radius by more than 65%. In vivo lens surfaces were fitted by biconicoids and Zernike polynomials after distortion correction. The anterior lens radii of curvature ranged from 10.27 to 14.14 mm, and the posterior lens radii of curvature ranged from 6.12 to 7.54 mm. Surface asphericities ranged from −0.04 to −1.96. The lens surfaces were well fitted by quadrics (with variation smaller than 2%, for 5-mm pupils), with low amounts of high order terms. Surface lens astigmatism was significant, with the anterior lens typically showing horizontal astigmatism (Z22 ranging from −11 to −1 µm) and the posterior lens showing vertical astigmatism (Z22 ranging from 6 to 10 µm). PMID:23082289
[Experience with Dohlman-Doane keratoprosthesis: case reports].
Stolz, Andressa Prestes; Kwitko, Sérgio; Dal Pizzol, Melissa Manfroi; Marinho, Diane; Rymer, Samuel
2008-01-01
To describe 9 eyes in 8 patients who received Dohlman-Doane type 1 keratoprosthesis (KPro) with a mean follow-up of 11.2 months (2 to 25 months). A retrospective, non-comparative interventional case series. Previous corneal disease was alcaline burn in 4 eyes, multiple graft failure in 3 eyes, Stevens-Johnson syndrome in 1 eye and thermal injury in 1 eye. Best corrected visual acuity (BCVA) was hand motions or worse in all patients. Glaucoma was present preoperatively in 3 eyes and received Ahmed valve implantation. 88,9% eyes achieved BCVA of better than or equal to 20/100, and 44,4% better than or equal to 20/40. In the postoperative period, 3 eyes developed posterior capsule opacity treated with YAG laser capsulotomy; 3 retroprosthetic membrane treated with tPA injection or steroids; 2 glaucoma in clinical treatment; 1 corneal melting, treated with donor cornea bottom exchange; and 1 fungic endophthalmitis, treated with corneal transplant, anterior vitrectomy, KPro and intraocular lens explantation, and specific intravitreal and endovenous treatment. Dohlman-Doane K-Pro seems to be a good option for cases of corneal blindness with poor prognosis for traditional penetrating keratoplasty. Its main advantage is not requesting systemic immunossuppression. Best results were achieved in non-immune diseases.
[Trial of "Huber Plus" in outpatients with chemotherapy by blood port system].
Matsumura, Natsuko; Tazumi, Keiko; Kouji, Keiko; Kondo, Motoi; Mizuki, Masao
2008-03-01
We evaluated the advantages and disadvantages of Huber Plus through three outpatients treated with central venous (CV) port chemotherapy (FOLFOX). One of the three outpatients first received chemotherapy with safety huber (Huber Plus) in this study, and the huber needle was changed from non-safety to a safety huber (Huber Plus) in two of the three outpatients. All three outpatients were taught about needle removal methods and port care. In patients? education, 1) we used a skin model and training CV port, and 2) dressing materials were used as film dressing plus three-point fixation by Fixomull stretch. As a result, the safety system assured zero incidents. Moreover, the evaluation revealed that operability and pain of Huber Plus were not clinical problems. We suggest that Huber Plus is applicable in outpatient chemotherapy and that our care plan with patients? education might become a standard treatment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, C; Lin, M; Chen, L
Purpose: Recent in vitro and in vivo experimental findings provided strong evidence that pulsed low-dose-rate radiotherapy (PLDR) produced equivalent tumor control as conventional radiotherapy with significantly reduced normal tissue toxicities. This work aimed to implement a PLDR clinical protocol for the management of recurrent cancers utilizing IMRT and VMAT. Methods: Our PLDR protocol requires that the daily 2Gy dose be delivered in 0.2Gy×10 pulses with a 3min interval between the pulses. To take advantage of low-dose hyper-radiosensitivity the mean dose to the target is set at 0.2Gy and the maximum dose is limited to 0.4Gy per pulse. Practical planning strategiesmore » were developed for IMRT and VMAT: (1) set 10 ports for IMRT and 10 arcs for VMAT with each angle/arc as a pulse; (2) set the mean dose (0.2Gy) and maximum dose (0.4Gy) to the target per pulse as hard constraints (no constraints to OARs); (3) select optimal port/arc angles to avoid OARs; and (4) use reference structures in or around target/OARs to reduce maximum dose to the target/OARs. IMRT, VMAT and 3DCRT plans were generated for 60 H and N, breast, lung, pancreas and prostate patients and compared. Results: All PLDR treatment plans using IMRT and VMAT met the dosimetry requirements of the PLDR protocol (mean target dose: 0.20Gy±0.01Gy; maximum target dose < 0.4Gy). In comparison with 3DCRT, IMRT and VMAT exhibited improved target dose conformity and OAR dose sparing. A single arc can minimize the difference in the target dose due to multi-angle incidence although the delivery time is longer than 3DCRT and IMRT. Conclusion: IMRT and VMAT are better modalities for PLDR treatment of recurrent cancers with superior target dose conformity and critical structure sparing. The planning strategies/guidelines developed in this work are practical for IMRT/VMAT treatment planning to meet the dosimetry requirements of the PLDR protocol.« less
Fibroblast growth factor receptor signaling is essential for lens fiber cell differentiation.
Zhao, Haotian; Yang, Tianyu; Madakashira, Bhavani P; Thiels, Cornelius A; Bechtle, Chad A; Garcia, Claudia M; Zhang, Huiming; Yu, Kai; Ornitz, David M; Beebe, David C; Robinson, Michael L
2008-06-15
The vertebrate lens provides an excellent model to study the mechanisms that regulate terminal differentiation. Although fibroblast growth factors (FGFs) are thought to be important for lens cell differentiation, it is unclear which FGF receptors mediate these processes during different stages of lens development. Deletion of three FGF receptors (Fgfr1-3) early in lens development demonstrated that expression of only a single allele of Fgfr2 or Fgfr3 was sufficient for grossly normal lens development, while mice possessing only a single Fgfr1 allele developed cataracts and microphthalmia. Profound defects were observed in lenses lacking all three Fgfrs. These included lack of fiber cell elongation, abnormal proliferation in prospective lens fiber cells, reduced expression of the cell cycle inhibitors p27(kip1) and p57(kip2), increased apoptosis and aberrant or reduced expression of Prox1, Pax6, c-Maf, E-cadherin and alpha-, beta- and gamma-crystallins. Therefore, while signaling by FGF receptors is essential for lens fiber differentiation, different FGF receptors function redundantly.
EGR distribution and fluctuation probe based on CO.sub.2 measurements
Parks, II, James E; Partridge, Jr., William P; Yoo, Ji Hyung
2015-04-07
A diagnostic system having a single-port EGR probe and a method for using the same. The system includes a light source, an EGR probe, a detector and a processor. The light source may provide a combined light beam composed of light from a mid-infrared signal source and a mid-infrared reference source. The signal source may be centered at 4.2 .mu.m and the reference source may be centered at 3.8 .mu.m. The EGR probe may be a single-port probe with internal optics and a sampling chamber with two flow cells arranged along the light path in series. The optics may include a lens for focusing the light beam and a mirror for reflecting the light beam received from a pitch optical cable to a catch optical cable. The signal and reference sources are modulated at different frequencies, thereby allowing them to be separated and the signal normalized by the processor.
NASA Technical Reports Server (NTRS)
Ansari, R. R.; Suh, K. I.; Dunker, S.; Kitaya, N.; Sebag, J.
2001-01-01
The non-invasive technique of dynamic light scattering (DLS) was used to quantitatively characterize vitreous and lens structure on a molecular level by measuring the sizes of the predominant particles and mapping the three-dimensional topographic distribution of these structural macromolecules in three spatial dimensions. The results of DLS measurements in five fresh adult bovine eyes were compared to DLS measurements in model solutions of hyaluronan (HA) and collagen (Coll). In the bovine eyes DLS measurements were obtained from excised samples of gel and liquid vitreous and compared to the model solutions. Measurements in whole vitreous were obtained at multiple points posterior to the lens to generate a three-dimensional 'map' of molecular structure. The macromolecule distribution in bovine lens was similarly characterized.In each bovine vitreous (Bo Vit) specimen, DLS predominantly detected two distinct particles, which differed in diffusion properties and hence size. Comparisons with model vitreous solutions demonstrated that these most likely corresponded to the Coll and HA components of vitreous. Three-dimensional mapping of Bo Vit found heterogeneity throughout the vitreous body, with different particle size distributions for Coll and HA at different loci. In contrast, the three-dimensional distribution of lens macromolecules was more homogeneous. Thus, the non-invasive DLS technique can quantitate the average sizes of vitreous and lens macromolecules and map their three-dimensional distribution. This method to assess quantitatively the macromolecular structure of vitreous and lens should be useful for clinical as well as experimental applications in health and disease. Copyright 2001 Academic Press.
A cost-effective peripheral venous port system placed at the bedside.
Finney, R; Albrink, M H; Hart, M B; Rosemurgy, A S
1992-07-01
High costs and a paucity of available operating time have led us to seek alternatives to operatively placed vascular access systems. This prospective study is the initial report of a peripheral port system (P.A.S. PORT System, Pharmacia Deltec, Inc.) placed at the bedside. Seventy-nine patients (52 male, 27 female), ages 3-92 years, had ports implanted by surgical residents with attending supervision. Sixty-eight (86%) received the P.A.S. PORT for long-term antibiotics, antifungal, or antiviral therapy; four (5%) for TPN infusion; three (4%) for blood products; two (3%) for chemotherapy; and two (3%) for iv narcotics. Ports were placed in 10 (13%) HIV(+) patients, three (4%) who were fully anticoagulated, and one who was a hemophiliac with a platelet count of zero. Eight patients (10%) developed superficial phlebitis, all of which resolved with nonsteroidal anti-inflammatory agents within 48 hr without port removal. Seven patients (9%) had their port removed due to infection. The average hospital charge to place the P.A.S. PORT System was $1488.00 vs $2811.00 for a tunneled external chest catheter and $3729.00 for the placement of a chest port. Bedside insertion of vascular access devices can be safely performed with acceptable infection rates allowing more efficient use of hospital operating rooms and with substantial cost savings.
Multimodal Freight Distribution to Support Increased Port Operations
DOT National Transportation Integrated Search
2016-10-01
To support improved port operations, three different aspects of multimodal freight distribution are investigated: (i) Efficient load planning for double stack trains at inland ports; (ii) Optimization of a multimodal network for environmental sustain...
Kawashima, Hirohiko; Nagai, Norihiro; Shinoda, Hajime; Tsubota, Kazuo; Ozawa, Yoko
2018-04-01
Recent progress in medical technology has resulted in improved surgical outcomes of pars plana vitrectomy (PPV); with microincision systems, the incidence of procedure-related complications during surgery has been reduced. However, unpredictable visual field defects after PPV remain an unresolved issue. A few reports have shown that damage to the retinal neurofibers owing to dry-up during air/fluid exchange or retinal neurotoxicity of the dye used to visualize the internal limiting membrane (ILM), as well as unintentional removal of retinal neurofibers during ILM peeling, are responsible for such visual field disorders. In this report, we present a case of extensive visual field defect due to optic neuropathy exhibiting vertical hemianopsia after PPV. A 50-year-old woman underwent PPV and cataract surgery for a macular hole and mild cataract under retrobulbar anesthesia with 3.5 mL of xylocaine. At the time of opening an infusion cannula for PPV, the intraocular lens was herniating, with an acute increase in pressure from the posterior eyeball; thus, intraocular pressure configuration level had to be decreased from the default level, whereas the other procedures including 20% SF6 injection were performed without any modification. The macular hole was closed postoperatively. However, the patient experienced nasal hemianopsia, which turned out to be optic neuropathy, as assessed via electric physiological examinations. The pattern of the visual field defect was not typical for glaucoma or anterior ischemic optic neuropathy. Her optic nerve head was pale at the temporal side soon after the surgery, and her blood pressure was low, suggesting that there may have been a congestion of the optic nerve feeder vessels because of the relatively high pressure in the orbit. The space occupancy with xylocaine and extensively stretched and plumped out eye ball with infusion during PPV may have pressed the surrounding tissue of the optic nerve and the feeder vessels. PPV is safe for most patients; however, individual variations in local and/or systemic conditions may cause complications. Future studies to optimize the surgical condition for each individual patient may be warranted.
Kim, Min-Seok; Yang, Hee Chul; Bae, Mi-Kyung; Cho, Sukki; Kim, Kwhanmien; Jheon, Sanghoon
2015-01-01
Background The aim of this study was to evaluate the feasibility of single-port video-assisted thoracic surgery (VATS) in the treatment of secondary spontaneous pneumothorax (SSP). Methods Twenty-four patients who were scheduled to undergo single-port VATS for SSP were studied. The medical records of the patients were retrospectively reviewed. The mean follow-up duration was 26.1±19.8 months. In order to evaluate the feasibility of single-port VATS for SSP, the postoperative results of single-port VATS (n=15) in patients with emphysema were compared with those of emphysematous patients who underwent three-port VATS (n=15) during the study period. Results Single-port VATS was feasible in 19 of 24 patients (79.2%), while an additional port was needed in five patients. In the single-port VATS patients, the median operation time, duration of chest tube drainage, and hospital stay were 84.0 minutes, one day, and two days, respectively. Postoperative complications included prolonged chest tube drainage for more than five days (n=1), wound infection (n=1), and vocal fold palsy (n=1). No recurrence of pneumothorax was observed during the follow-up period. The median operation time, duration of chest tube drainage, and hospital stay of the emphysematous patients who underwent single-port VATS were shorter than those who underwent three-port VATS group (p<0.05 for all parameters). Conclusion Single-port VATS proved to be a feasible procedure in the treatment of patients with secondary spontaneous pneumothorax. PMID:26665104
Novel fabrication technique of hybrid structure lens array for 3D images
NASA Astrophysics Data System (ADS)
Lee, Junsik; Kim, Junoh; Kim, Cheoljoong; Shin, Dooseub; Koo, Gyohyun; Won, Yong Hyub
2016-03-01
Tunable liquid lens arrays can produce three dimensional images by using electrowetting principle that alters surface tensions by applying voltage. This method has advantages of fast response time and low power consumption. However, it is challenging to fabricate a high fill factor liquid lens array and operate three dimensional images which demand high diopter. This study describes a hybrid structure lens array which has not only a liquid lens array but a solid lens array. A concave-shape lens array is unavoidable when using only the liquid lens array and some voltages are needed to make the lens flat. By placing the solid lens array on the liquid lens array, initial diopter can be positive. To fabricate the hybrid structure lens array, a conventional lithographic process in semiconductor manufacturing is needed. A negative photoresist SU-8 was used as chamber master molds. PDMS and UV adhesive replica molding are done sequentially. Two immiscible liquids, DI water and dodecane, are injected in the fabricated chamber, followed by sealing. The fabricated structure has a 20 by 20 pattern of cylindrical shaped circle array and the aperture size of each lens is 1mm. The thickness of the overall hybrid structure is about 2.8mm. Hybrid structure lens array has many advantages. Solid lens array has almost 100% fill factor and allow high efficiency. Diopter can be increased by more than 200 and negative diopter can be shifted to the positive region. This experiment showed several properties of the hybrid structure and demonstrated its superiority.
Gabr, Hesham; Chen, Xi; Zevallos-Carrasco, Oscar M; Viehland, Christian; Dandrige, Alexandria; Sarin, Neeru; Mahmoud, Tamer H; Vajzovic, Lejla; Izatt, Joseph A; Toth, Cynthia A
2018-01-10
To evaluate the use of live volumetric (4D) intraoperative swept-source microscope-integrated optical coherence tomography in vitrectomy for proliferative diabetic retinopathy complications. In this prospective study, we analyzed a subgroup of patients with proliferative diabetic retinopathy complications who required vitrectomy and who were imaged by the research swept-source microscope-integrated optical coherence tomography system. In near real time, images were displayed in stereo heads-up display facilitating intraoperative surgeon feedback. Postoperative review included scoring image quality, identifying different diabetic retinopathy-associated pathologies and reviewing the intraoperatively documented surgeon feedback. Twenty eyes were included. Indications for vitrectomy were tractional retinal detachment (16 eyes), combined tractional-rhegmatogenous retinal detachment (2 eyes), and vitreous hemorrhage (2 eyes). Useful, good-quality 2D (B-scans) and 4D images were obtained in 16/20 eyes (80%). In these eyes, multiple diabetic retinopathy complications could be imaged. Swept-source microscope-integrated optical coherence tomography provided surgical guidance, e.g., in identifying dissection planes under fibrovascular membranes, and in determining residual membranes and traction that would benefit from additional peeling. In 4/20 eyes (20%), acceptable images were captured, but they were not useful due to high tractional retinal detachment elevation which was challenging for imaging. Swept-source microscope-integrated optical coherence tomography can provide important guidance during surgery for proliferative diabetic retinopathy complications through intraoperative identification of different complications and facilitation of intraoperative decision making.
[Technical aspects of measurement for optically sophisticated eyeglasses].
Guilino, G
1988-07-01
This paper deals with the question of how aspherical ophthalmic lenses can be measured outside the reference point given by the manufacturer in order to make a lens comparison or to test the shape faithfulness of the lens surface. Three procedures are presented with measuring examples - vertex power measurement with swiveled lens mount, probe scan in a three-coordinate measurement, and interferometer measurement using a non-ideal reference lens. The basic problem inherent in an application-related interpretation of the measuring data sets gained by these methods is shown.
Freight movement, port facilities, and economic competitiveness.
DOT National Transportation Integrated Search
2014-07-01
This research report examines how the Panama Canal expansion will affect freight at three ports, truck movement : between the ports and inland economic hubs and the economic impacts accompanying the shift in cargo shipping : patterns. Economic impact...
Signs of fetal brain sparing are not related to umbilical cord blood gases at birth.
Cheema, Riffat; Dubiel, Mariusz; Gudmundsson, Saemundur
2009-07-01
Fetal chronic hypoxia leads to centralization of circulation in order to spare the vital organs brain, adrenals and the heart. This can be documented by Doppler ultrasound. Increased blood velocity in the fetal middle cerebral artery (MCA) is an acknowledged sign of centralization of circulation in chronic hypoxia, and is called brain sparing. Our aim was to assess the relationship between signs of brain sparing in the MCA and umbilical cord blood gases at birth. A prospective study. Singleton 57 high-risk pregnancies (outcome was compared with 21 normal pregnancies). MCA Doppler was performed within 24 h of elective caesarean section in high-risk pregnancies. Umbilical cord blood gases were analysed at birth. Cord blood gases were related to signs of centralization of fetal circulation in the MCA. No correlation between signs of brain sparing in the MCA and cord blood gases. Apgar score at 5'<7 was seen in three newborns, but only one of these had antenatal signs of brain sparing. Newborns with antenatal brain sparing were admitted more often (p<0.04) and had a longer duration of stay in NICU (p<0.03) compared to newborns without brain sparing. Decreased pulsatility index in MCA is an acknowledged sign of fetal centralization of circulation during chronic hypoxia. However, signs of brain sparing are not related to cord blood gases at birth, which might suggest that redistribution of fetal circulation can maintain normal blood gases for a long time during chronic hypoxia.
2001-08-06
KENNEDY SPACE CENTER, Fla. -- On Launch Pad 39A, Discovery’s payload bay doors close on the payloads inside. On the Integrated Cargo Carrier seen here is the Early Ammonia Servicer (EAS) on the left. The EAS contains spare ammonia for the Station’s cooling system. Ammonia is the fluid used in the radiators that cool the Station’s electronics. The EAS will be installed on the P6 truss holding the giant U.S. solar arrays, batteries and cooling radiators. Other payloads in the bay are the Multi-Purpose Logistics Module Leonardo, filled with laboratory racks of science equipment and racks and platforms of experiments and supplies, and various experiments attached on the port and starboard adapter beams. Discovery is scheduled to be launched Aug. 9, 2001
Progressive addition spectacle lenses: Design preferences and head movements while reading
NASA Astrophysics Data System (ADS)
Preston, Julie Lynn
In a subjective preference study, two key progressive addition lens parameters, near zone width and corridor length, were varied in a double-masked, randomized, clinical trial of 49 patients. Each subject received a complete eye examination and a new frame. Each wore 6 pairs of lenses for one week at a time and completed questionnaires relating to vision, adaptation, and satisfaction. The preferred lens was identified from the three near zone width lenses and from the three corridor length lenses. Patient characteristics were analyzed for their effect on design preference. Satisfaction ratings following a brief experience with each design were compared to ratings after one week of wear in order to ascertain the predictability of initial impressions. One lens design appeared twice in the preference trial, providing an assessment of the repeatability of the rating instrument. The lens design with the widest near zone was rated significantly lower than the other near zone width designs for nearly every question relating to vision, adaptation, and satisfaction. This lens was also least preferred of all the designs. Preferences for corridor length were evenly distributed among the three designs. Of patient characteristics, years of progressive addition lens wear and gender significantly affected design preference in this population. Initial impressions were not predictive of satisfaction after a week of wear. The rating instrument was judged to have low repeatability. In the head movement portion of the study, 18 participants from the preference study wore the three near zone width designs while reading three paragraphs of varying print size. From a 20 second recording for each of three different paragraphs with each lens, measures of head rotation and posture were collected. The amplitude of head rotation was significantly affected by print size but not by lens design. The effective zone widths on the lenses scanned by the eyes and the locations of the reading levels were calculated from the head rotation and posture data. Effective zone widths were narrower than the contour plot widths for each condition.
Circuit design for the retina-like image sensor based on space-variant lens array
NASA Astrophysics Data System (ADS)
Gao, Hongxun; Hao, Qun; Jin, Xuefeng; Cao, Jie; Liu, Yue; Song, Yong; Fan, Fan
2013-12-01
Retina-like image sensor is based on the non-uniformity of the human eyes and the log-polar coordinate theory. It has advantages of high-quality data compression and redundant information elimination. However, retina-like image sensors based on the CMOS craft have drawbacks such as high cost, low sensitivity and signal outputting efficiency and updating inconvenience. Therefore, this paper proposes a retina-like image sensor based on space-variant lens array, focusing on the circuit design to provide circuit support to the whole system. The circuit includes the following parts: (1) A photo-detector array with a lens array to convert optical signals to electrical signals; (2) a strobe circuit for time-gating of the pixels and parallel paths for high-speed transmission of the data; (3) a high-precision digital potentiometer for the I-V conversion, ratio normalization and sensitivity adjustment, a programmable gain amplifier for automatic generation control(AGC), and a A/D converter for the A/D conversion in every path; (4) the digital data is displayed on LCD and stored temporarily in DDR2 SDRAM; (5) a USB port to transfer the data to PC; (6) the whole system is controlled by FPGA. This circuit has advantages as lower cost, larger pixels, updating convenience and higher signal outputting efficiency. Experiments have proved that the grayscale output of every pixel basically matches the target and a non-uniform image of the target is ideally achieved in real time. The circuit can provide adequate technical support to retina-like image sensors based on space-variant lens array.
Maritime security report. June 1999 [Inter-American Port Security Program
DOT National Transportation Integrated Search
1999-06-01
Three international port security training courses were organized and managed by the U.S. Maritime Administration (MARAD) and conducted during the fall of 1998 in Panama, Peru, and Barbados as principal activities of the Inter-American Port Security ...
Three-dimensional microscopic tomographic imagings of the cataract in a human lens in vivo
NASA Astrophysics Data System (ADS)
Masters, Barry R.
1998-10-01
The problem of three-dimensional visualization of a human lens in vivo has been solved by a technique of volume rendering a transformed series of 60 rotated Scheimpflug (a dual slit reflected light microscope) digital images. The data set was obtained by rotating the Scheimpflug camera about the optic axis of the lens in 3 degree increments. The transformed set of optical sections were first aligned to correct for small eye movements, and then rendered into a volume reconstruction with volume rendering computer graphics techniques. To help visualize the distribution of lens opacities (cataracts) in the living, human lens the intensity of light scattering was pseudocolor coded and the cataract opacities were displayed as a movie.
Adachi, Naho; Munesada, Minako; Yamada, Noriko; Suzuki, Haruka; Futohashi, Ayano; Shigeeda, Takashi; Kato, Satoshi; Nishigaki, Masakazu
2014-06-01
Postoperative face-down posturing (FDP) is recommended to optimize the effects of intraocular gas tamponade after vitrectomy. However, patients undergoing FDP usually experience physical and psychological burdens. This 3-armed, randomized, single-center trial investigated the effects of aromatherapy on FDP-related physical pain. Sixty-three patients under FDP were randomly allocated to one of three treatment groups: aromatherapy massage with essential oil (AT), oil massage without essential oil (OT), and a control group. The AT and OT groups received 10 minutes of massage by ward nurses trained by an aromatherapist, while the control group received usual care. Outcomes were assessed as short-term (pre- to post-intervention) and long-term (first to third postoperative day) changes in physical pain in five body regions using face-scale. The AT and OT groups both revealed similar short-term pain reductions after intervention, compared with the control group. Regarding long-term effects, neither group experienced significant effects until the second day. Significantly more pain reduction compared with usual care occurred on the third day, mainly in the AT group, though there were few significant differences between the AT and OT groups. In conclusion, this study suggests that simple oil massage is an effective strategy for immediate pain reduction in patients undergoing FDP, while aromatherapy may have a long-term effect on pain reduction. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Nd:YAG laser vitreolysis versus pars plana vitrectomy for vitreous floaters.
Kokavec, Jan; Wu, Zhichao; Sherwin, Justin C; Ang, Alan Js; Ang, Ghee Soon
2017-06-01
The vitreous is the clear jelly of the eye and contains fine strands of proteins. Throughout life the composition of this vitreous changes, which causes the protein strands in it to bundle together and scatter light before it reaches the retina. Individuals perceive the shadows cast by these protein bundles as 'floaters'. Some people are so bothered by floaters that treatment is required to control their symptoms. Two major interventions for floaters include Nd:YAG laser vitreolysis and vitrectomy. Nd:YAG laser vitreolysis involves using laser energy to fragment the vitreous opacities via a non-invasive approach. Vitrectomy involves the surgical replacement of the patient's vitreous (including the symptomatic vitreous floaters) with an inert and translucent balanced salt solution, through small openings in the pars plana. To compare the effectiveness and safety of Nd:YAG laser vitreolysis to pars plana vitrectomy for symptomatic vitreous floaters. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 12), MEDLINE Ovid (1946 to 17 January 2017), Embase Ovid (1947 to 17 January 2017), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 17 January 2017), the ISRCTN registry (www.isrctn.com/editAdvancedSearch); searched 17 January 2017, ClinicalTrials.gov (www.clinicaltrials.gov); searched 17 January 2017 and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 17 January 2017. We did not use any date or language restrictions in the electronic searches for trials. We also searched conference proceedings to identify additional studies. We included only randomised controlled trials (RCTs) that compared Nd:YAG laser vitreolysis to pars plana vitrectomy for treatment of symptomatic floaters. We planned to use methods recommended by Cochrane. The primary outcome we planned to measure was change in vision-related quality of life from baseline to 12 months, as determined by a vision-related quality of life questionnaire. The secondary outcomes we planned to measure were best corrected logMAR or Snellen visual acuity at 12 months for the treated eye(s) and costs. Adverse outcomes we planned to record were the occurrence of sight-threatening complications by 12 months (asymptomatic retinal tears, symptomatic retinal tears, retinal detachment, cataract formation, and endophthalmitis). No studies met the inclusion criteria of this review. There are currently no RCTs that compare Nd:YAG laser vitreolysis with pars plana vitrectomy for the treatment of symptomatic floaters. Properly designed RCTs are needed to evaluate the treatment outcomes from the interventions described. We recommend future studies randomise participants to either a Nd:YAG laser vitreolysis group or a vitrectomy group, with participants in each group assigned to either receive treatment or a sham intervention. Future studies should follow participants at six months and 12 months after the intervention. Also they should use best corrected visual acuity (BCVA) using an Early Treatment of Diabetic Retinopathy Study (ETDRS) chart read at 4 metres, vision-related quality of life (VRQOL), and adverse outcomes as the outcome measures of the trial.
Vaginal blood flow after radical hysterectomy with and without nerve sparing. A preliminary report.
Pieterse, Q D; Ter Kuile, M M; Deruiter, M C; Trimbos, J B M Z; Kenter, G G; Maas, C P
2008-01-01
Radical hysterectomy with pelvic lymphadenectomy (RHL) for cervical cancer causes damage to the autonomic nerves, which are responsible for increased vaginal blood flow during sexual arousal. The aim of the study of which we now report preliminary data was to determine whether a nerve-sparing technique leads to an objectively less disturbed vaginal blood flow response during sexual stimulation. Photoplethysmographic assessment of vaginal pulse amplitude (VPA) during sexual stimulation by erotic films was performed. Subjective sexual arousal was assessed after each stimulus. Thirteen women after conventional RHL, 10 women after nerve-sparing RHL, and 14 healthy premenopausal women participated. Data were collected between January and August 2006. The main outcome measure was the logarithmically transformed mean VPA. To detect statistically significant differences in mean VPA levels between the three groups, a univariate analysis of variance was used. Mean VPA differed between the three groups (P= 0.014). The conventional group had a lower vaginal blood flow response than the control group (P= 0.016), which tended also to be lower than that of the nerve-sparing group (P= 0.097). These differences were critically dependent on baseline vaginal blood flow differences between the groups. The conventional group follows a vaginal blood flow pattern similar to postmenopausal women. Conventional RHL is associated with an overall disturbed vaginal blood flow response compared with healthy controls. Because it is not observed to the same extent after nerve-sparing RHL, it seems that the nerve-sparing technique leads to a better overall vaginal blood flow caused by less denervation of the vagina.
Colohan, Shannon; Wong, Corrine; Lakhiani, Chrisovalantis; Cheng, Angela; Maia, Munique; Arbique, Gary; Saint-Cyr, Michel
2012-12-01
Increasing focus on reducing morbidity from latissimus dorsi flaps has led to the evolution of muscle-sparing variants and perforator-based flaps. This study aimed to investigate the vascular anatomy of the muscle-sparing variant and to describe its application as a free flap based on the descending branch of the thoracodorsal artery. Twelve fresh cadavers underwent anatomical dissection and angiographic injection studies of the thoracodorsal arterial system. The musculocutaneous territories of the descending and transverse branches to the latissimus dorsi muscle were identified and assessed using three-dimensional reconstruction software of computed tomography imaging results. In the clinical study, five patients underwent reconstruction of a variety of defects using the free descending branch muscle-sparing latissimus dorsi flap. Three- and four-dimensional (computed tomography) angiography demonstrated perfusion of the latissimus dorsi muscle by the transverse and descending branches, with overlap of vascular territories via cross-linking vessels. The descending branch supplied a slightly greater cutaneous area overlying the muscle, although differences between both branches were not significant (p = 0.76). In the clinical study, the free muscle-sparing latissimus dorsi flap provided excellent coverage with no flap complications or seroma. The free muscle-sparing latissimus dorsi flap based on the descending branch of the thoracodorsal artery is a viable reconstructive option. Significant collateral flow between vessels allows for larger flap harvest than would be expected. The flap is technically simple to harvest, provides a large perfusion area, and is a reliable variant of the full latissimus dorsi flap. Therapeutic, V.
Performance of three multipurpose disinfecting solutions with a silicone hydrogel contact lens.
García-Porta, Nery; Rico-del-Viejo, Laura; Ferreira-Neves, Helena; Peixoto-de-Matos, Sofia C; Queirós, Antonio; González-Méijome, José M
2015-01-01
To evaluate the clinical performance of a silicone hydrogel (Si-Hy) soft contact lens (CL) in combination with three different multipurpose disinfecting solutions (MPDSs). This was a prospective, randomized, single-masked, crossover, and comparative study in which 31 habitual soft CL wearers were randomly assigned to one of the three MPDSs (Synergi, COMPLETE RevitaLens, and OPTI-FREE PureMoist) for 1 month with a 1-week wash-out period between each exposure. All subjects were successfully refitted with a Si-Hy CL (Biofinity). Subjects were then scheduled for follow-up visits after 1 month of lens wear, being evaluated at 2 and 8 hours after lens insertion. Visual Analogue Scales (VAS) were used to gauge comfort rating. The tarsal conjunctiva showed a significantly different degree of lid redness between the MPDSs at the 2-hour visit (P < 0.05, Kruskal-Wallis test), being lower for COMPLETE RevitaLens compared to the other two MPDSs (Mann-Whitney U test). Furthermore, a significantly different degree of lid roughness at the 8-hour visit was seen (P < 0.05, Kruskal-Wallis test), being higher for Synergi (Mann-Whitney U test). The subjective comfort was similar with the three MPDSs. Tarsal conjunctival response should be also considered in the context of the clinical performance of MPDs at the ocular surface.
Estimating economic impacts of regulatory changes to U.S. port operations
DOT National Transportation Integrated Search
2007-03-01
This report describes a framework constructed to assist in understanding the long run : impacts of regulations proposed by the US Coast Guard on domestic marine ports. The : port impacts considered pertain to cost, time and reliability. These three f...
Sadrolsadat, Seyed Hossein; Yousefshahi, Fardin; Ostadalipour, Abbas; Mohammadi, Fatemeh Zahra; Makarem, Jalil
2017-06-01
Nowadays, pain, nausea, and vomiting are regarded as important complications of anesthesia and surgery. The current study aimed at assessing the effect of preemptive intravenous acetaminophen on control of pain, nausea, vomiting, shivering, and drowsiness following the general anesthesia for retina and/or vitrectomy surgeries. In a randomized, double-blind, clinical trial, 83 candidates for retina or vitrectomy eye surgery under general anesthesia were distributed into 3 groups: A) 41 patients in the control group who received 100 mL of normal saline just before the surgery and 100 mL of normal saline 20 minutes before the end of surgery; B) 21 patients in the preemptive group who received acetaminophen 15 mg/kg in 100 mL normal saline just before the surgery and 100 mL normal saline 20 minutes before the end of surgery; C) 21 patients in the preventive group who received 100 mL normal saline just before the surgery and acetaminophen 15 mg/kg in 100 mL normal saline 20 minutes before the end of surgery. Pain, nausea, vomiting, and shivering were assessed at the recovery and 2, 4, and 24 hours after the operation. Anesthesia emergence situation was assessed after arrival in the recovery room by the Richmond agitation-sedation scale (RASS) questionnaire. Blood pressure and heart rate were recorded before anesthesia induction, just after intubation, before extubation, and on discharge from the recovery room. Total intraoperative fentanyl, duration of operation, and duration of anesthesia were not different among the studied groups. Vital signs were not statistically different among the groups at before anesthesia induction, just after intubation, before extubation, and on discharge from the recovery room. Thirty-three patients in the control group (87.8%), 11 in preemptive (52.4%), and 14 in preventive groups (66.7%) needed acetaminophen in the first 24 hours after the surgery (P value = 0.008). Pain scores measured by visual rating scale (VRS) was lower in the preemptive and preventive groups, compared with those of the control group, in the recovery (P value = 0.006), 2 hours after the surgery (P value = 0.008), and 4 hours after the surgery (P value = 0.012), but not in 24 hours after the operation (P value = 0.1). Intravenous acetaminophen administered as preemptive or preventive medication was effective and safe to control acute postoperative pain and analgesic request after the vitrectomy eye surgery.
Sadrolsadat, Seyed Hossein; Yousefshahi, Fardin; Ostadalipour, Abbas; Mohammadi, Fatemeh Zahra; Makarem, Jalil
2017-01-01
Background Nowadays, pain, nausea, and vomiting are regarded as important complications of anesthesia and surgery. The current study aimed at assessing the effect of preemptive intravenous acetaminophen on control of pain, nausea, vomiting, shivering, and drowsiness following the general anesthesia for retina and/or vitrectomy surgeries. Methods In a randomized, double-blind, clinical trial, 83 candidates for retina or vitrectomy eye surgery under general anesthesia were distributed into 3 groups: A) 41 patients in the control group who received 100 mL of normal saline just before the surgery and 100 mL of normal saline 20 minutes before the end of surgery; B) 21 patients in the preemptive group who received acetaminophen 15 mg/kg in 100 mL normal saline just before the surgery and 100 mL normal saline 20 minutes before the end of surgery; C) 21 patients in the preventive group who received 100 mL normal saline just before the surgery and acetaminophen 15 mg/kg in 100 mL normal saline 20 minutes before the end of surgery. Pain, nausea, vomiting, and shivering were assessed at the recovery and 2, 4, and 24 hours after the operation. Anesthesia emergence situation was assessed after arrival in the recovery room by the Richmond agitation-sedation scale (RASS) questionnaire. Blood pressure and heart rate were recorded before anesthesia induction, just after intubation, before extubation, and on discharge from the recovery room. Results Total intraoperative fentanyl, duration of operation, and duration of anesthesia were not different among the studied groups. Vital signs were not statistically different among the groups at before anesthesia induction, just after intubation, before extubation, and on discharge from the recovery room. Thirty-three patients in the control group (87.8%), 11 in preemptive (52.4%), and 14 in preventive groups (66.7%) needed acetaminophen in the first 24 hours after the surgery (P value = 0.008). Pain scores measured by visual rating scale (VRS) was lower in the preemptive and preventive groups, compared with those of the control group, in the recovery (P value = 0.006), 2 hours after the surgery (P value = 0.008), and 4 hours after the surgery (P value = 0.012), but not in 24 hours after the operation (P value = 0.1). Conclusions Intravenous acetaminophen administered as preemptive or preventive medication was effective and safe to control acute postoperative pain and analgesic request after the vitrectomy eye surgery. PMID:29181331
Solinas, Gianfranca; Platini, Francesca; Trivellato, Maurizio; Rigo, Carla; Alabiso, Oscar; Galetto, Alessandra S
2017-07-14
Patients with cancer need stable venous access using central vascular devices like central venous ports and peripherally inserted central catheters that can be used for a wide range of indications. Numerous flushing protocols exist including different frequencies for catheter locking to maintain catheter patency. The aim of this retrospective study was to evaluate the incidence of lumen occlusion of central venous ports in a group of adult cancer patients, adopting a policy of locking with normal saline every three months. This is a single-center retrospective observational study. During follow-up, we analyzed adult cancer patients who had undergone port insertion from January 1st, 2007 to August 31st, 2014. Flushing and locking were performed every three months with a syringe containing normal saline. We collected data from 381 patients with ports inserted in subclavian vein (379 patients) and in the right jugular vein (2 patients). Locking was performed during 3-monthly follow-up visits. Median follow-up was 810 days (90-2700 days). Among 381 ports, 59 were removed; the reasons for removal were: end of use (45 cases), catheter rupture (9 cases), dislocation (3 cases) and catheter-related bloodstream infection (2 cases). We had no reports of lumen occlusion. Our data suggest that locking ports with normal saline every three months is not associated with an increased risk of lumen occlusion.
Batman, C; Ozdamar, Y; Mutevelli, S; Sonmez, K; Zilelioglu, G; Karakaya, J
2009-06-01
To describe the use of tissue glue to close scleral and conjunctival wounds, and to compare the clinical outcomes using tissue glue and vicryl suture for closing these areas in conventional 20-gauge (G) vitrectomy. Thirty eyes of 30 patients were included in this study. The indications for vitreoretinal surgery were diabetic vitreous haemorrhage with severe vitreoretinal traction in 10 eyes, retinal detachment and proliferative vitreoretinopathy in 14 eyes, and vitreous opacity in 6 eyes. Tissue glue (Tisseel, Baxter AG Industries, Vienna, Austria) was used to attach scleral and conjunctival wounds in 15 eyes and vicryl sutures in 15 eyes. The patients were allotted into two subgroups as tissue glue group (TG) and vicryl suture group (VG). The sclerotomy sites were evaluated with ultrasound biomicroscopy (UBM) postoperatively in TG. Follow-up period was 2 months. The groups were statistically compared for ocular signs and symptoms by Mann-Whitney U-test. No scleral wound leakage and conjunctival reattachment were observed at the end of the surgical procedure and during the follow-up period. No adverse effects were seen in TG. Abnormal fibrous ingrowth was not detected at the sclerotomy sites by means of UBM in TG. Patient comfort was significantly higher in TG than VG (P<0.05). Tissue glue has no adverse effects on ocular tissue and can be used as a substitute for suture materials, and the use of tissue glue decreases patient symptoms during the postoperative period after 20-G vitrectomy. Tissue glue can enable to perform sutureless surgery in the conventional 20-G vitrectomy.
[Vitrectomy for idiopathic and secondary preretinal macular membrane].
Oficjalska-Młyńczak, Jolanta; Jamrozy-Witkowska, Agnieszka
2004-01-01
To evaluate the results of pars plana vitrectomy and membrane stripping for idiopathic and secondary preretinal macular membrane (PMM). Twenty one consecutive subjects (21 eyes) ranging in age from 40 to 78 (mean 66.9) with PMM underwent vitrectomy and membrane peeling. 17 cases had membranes that were considered idiopathic, and 4 cases were associated with other disorders: 3 occurred after successful retinal reattachment surgery, 1--after laserotherapy in the course of diabetic retinopathy. Visual acuity (VA), Amsler grid, and postoperative complications were assessed. The follow-up was 1 to 22 months, mean 5.7. Visual acuity improved postoperatively in 15 eyes (71.4%), at least two lines on the Snellen chart in 8 eyes (38.1%), entirely in patients with idiopathic PMM. It remained unchanged in 3 eyes (14.3%) and deteriorated in 3 eyes (14.3%). Eyes with transparent membrane showed greater visual improvement than opaque ones. The preoperative Amsler test was positive in 15 patients (71.4%), postoperatively--in 4 cases (19%). 2 idiopathic cases with VA of 0.7 showed postoperatively VA of 1.0. Complications included retinal detachment in 2 eyes (1 in idiopathic and 1 in secondary PMM), and development of nuclear sclerotic cataract in 2 eyes. At 6 months of follow-up, a residual membrane formation in 1 cases appeared. Macular pseudohole was observed in 1 eye with no impact on visual results. 1. Vitrectomy with membrane peeling for preretinal macular membrane provides improvement in visual acuity and reduces metamorphopsia 2. Thin, cellophane-like appearance of the membrane gives a better prognosis of visual function improvement.
Ulrich, Jan Niklas
2017-01-01
Diabetes mellitus remains the leading cause of blindness among working age Americans with diabetic macular edema being the most common cause for moderate and severe vision loss. To investigate the anatomical and visual benefits of pars plana vitrectomy with inner limiting membrane peeling in patients with nontractional diabetic macular edema as well as correlation of integrity of outer retinal layers on spectral domain optical coherence tomography to visual outcomes. We retrospectively reviewed the charts of 42 diabetic patients that underwent vitrectomy with internal limiting membrane peeling for nontractional diabetic macula edema. The integrity of outer retinal layers was evaluated and preoperative central macular thickness and visual acuity were compared with data at 1 month, 3 months and 6 months postoperatively. The student t-test was used to compare the groups. 31 eyes were included. While no differences were seen at 1 and 3 months, there was significant improvement of both central macular thickness and visual acuity at the 6 months follow up visit compared to preoperatively (357, 427 microns; p=0.03. 20/49, 20/82; p=0.03) . Patients with intact external limiting membrane and ellipsoid zone had better preoperative vision than patients with outer retinal layer irregularities (20/54, 20/100; p=0.03) and greater visual gains postoperatively (20/33, p<0.001 versus 20/81; p=non-significant). Pars plana vitrectomy with internal limiting membrane peeling can improve retinal anatomy and visual acuity in patients with nontractional diabetic macular edema. Spectral domain optical coherence tomography may help identify patients with potential for visual improvement.
Chelala, Elias; Nehme, Joseph; El Rami, Hala; Aoun, Roni; Dirani, Ali; Fadlallah, Ali; Jalkh, Alex
2018-06-01
To investigate the efficacy of intravitreal ranibizumab injections in proliferative diabetic retinopathy associated with vitreous hemorrhage (VH). A prospective study including patients with proliferative diabetic retinopathy who presented with persistent VH. Vitreous hemorrhage was graded into mild, moderate, and severe. Patients were randomized into two groups: the ranibizumab group was treated with intravitreal injections of ranibizumab and the control group was assigned to observation alone. Vitrectomy was performed if there was any aggravation of the VH in patients with mild, moderate, and severe VH or in the absence of improvement by 16 weeks in patients with moderate and severe VH. The ranibizumab group included 71 patients and the control group included 62 patients. There was a statistically significant difference in the vitrectomy rate in patients with mild-to-moderate VH (5 patients [7.04%] and 12 patients [19.35%], respectively; P = 0.04). However, there was no statistically significant difference in the overall vitrectomy rate, and in the vitrectomy rate in severe VH (17 [23.94%] and 12 [16.90%] patients in the ranibizumab group vs. 22 [35.48%] and 10 [16.13%] patients in the control group, P = 0.14 and P = 0.83, respectively). Recurrence of the VH occurred in 22 patients in the ranibizumab group and 29 patients in the control group (P = 0.06). Better visual acuity measurements were recorded on all follow-up visits in the ranibizumab group (P ≤ 0.04). Intravitreal ranibizumab injections could be considered in proliferative diabetic retinopathy patients with mild and moderate VH.
Three-port beam splitter of a binary fused-silica grating.
Feng, Jijun; Zhou, Changhe; Wang, Bo; Zheng, Jiangjun; Jia, Wei; Cao, Hongchao; Lv, Peng
2008-12-10
A deep-etched polarization-independent binary fused-silica phase grating as a three-port beam splitter is designed and manufactured. The grating profile is optimized by use of the rigorous coupled-wave analysis around the 785 nm wavelength. The physical explanation of the grating is illustrated by the modal method. Simple analytical expressions of the diffraction efficiencies and modal guidelines for the three-port beam splitter grating design are given. Holographic recording technology and inductively coupled plasma etching are used to manufacture the fused-silica grating. Experimental results are in good agreement with the theoretical values.
Gaber, Raouf; You, Qi Sheng; Muftuoglu, Ilkay Kilic; Alam, Mostafa; Tsai, Frank F; Mendoza, Nadia; Freeman, William R
2017-11-01
To evaluate the incidence, characteristics, and the progression of epiretinal membrane (ERM) remnant edge seen by optical coherence tomography after ERM peeling. A retrospective chart review was conducted for 86 eyes of 85 consecutive patients who were diagnosed with ERM and underwent pars plana vitrectomy for epiretinal membrane peeling between 2013 and 2014. Data collected and analyzed included age, gender, preoperative and postoperative visual acuity, use of indocyanine green dye to stain internal limiting membrane, tamponade used after vitrectomy, ERM edge boundaries, presence of cystoid macular edema, and central foveal thickness. An ERM remnant edge was detected in 33/86 study eyes (38.4%) at the first postoperative optical coherence tomography scan. Compared with those without an ERM remnant, patients with an ERM remnant after surgery were significantly older at baseline and had a higher incidence of ERM recurrence at their last visit. They were not significantly different in terms of gender, preoperative and postoperative visual acuity, reduction of central foveal thickness from baseline, proportion of eyes with preoperative ERM elevation on optical coherence tomography, presence of macular edema before surgery, intraoperative use of indocyanine green staining for ILM peeling, or tamponade used. Based on the edge morphology, we classified the ERM remnant into three types: Type 1 was flat and blended with the retina (14/33 eyes, 42.4%), Type 2 was flat but stepped (17/33 eyes, 51.5%), and Type 3 was elevated (2/33 eyes, 6.0%). A significantly higher risk of ERM recurrence was seen in Type 2 and Type 3 ERM remnants (75% and 100%, respectively) than Type 1 ERM remnants (10%). An ERM remnant edge was detected by optical coherence tomography after ERM peeling in 38.4% of eyes. The presence of a postoperative ERM edge was associated with a higher risk of ERM recurrence, particularly in Type 2 and Type 3 ERM remnants.
Hamoudi, Hassan; Christensen, Ulrik Correll; La Cour, Morten
2017-08-01
To assess the impact of sequential and combined surgery [cataract surgery and 23-gauge pars plana vitrectomy (PPV) with peeling] on corneal endothelium cell density (CED) and corneal biomechanical characteristics. Phakic eyes with epiretinal membrane (ERM) were prospectively allocated to (i) cataract surgery and subsequent PPV (CAT group), (ii) PPV and subsequent cataract surgery (VIT group) or (iii) phacovitrectomy (COMBI group). Eyes were examined at baseline, 1 month after each surgery, and at 3 and 12 months follow-up. Corneal endothelium cell density (CED) was assessed with non-contact specular microscopy. Pachymetry [central cornea thickness (CCT)], keratometry and cornea volume (CV) were measured with Pentacam Scheimpflug camera. Primary outcome was change in CED after 12 months; secondary outcomes were changes in CCT and CV after 12 months. Sixty-two eyes were enrolled and allocated to the three groups. The mean preoperative CED was 2776, 2794 and 2653 cells/mm 2, which decreased significantly at 12 months by 15.3, 20.0 and 19.3% in the CAT, VIT and COMBI group. There was no significant difference in percentage cell loss between the groups at final follow-up. The CED decreased significantly after cataract surgery, but was unaffected by PPV. Central cornea thickness (CCT) increased by 10 μm (p = 0.005) and CV by 1.38 mm 3 (2.3%, p < 0.001) in the COMBI group. There were no significant differences in CCT or CV between the groups at final follow-up. Combined and sequential surgery in ERM leads to a small decrease in CED. Performing cataract surgery before, after or in combination with vitrectomy did not make any significant difference with respect to final CED, CCT or CV. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Effect of lens care system on silicone hydrogel contact lens wettability.
Guillon, Michel; Maissa, Cécile; Wong, Stéphanie; Patel, Trisha; Garofalo, Renée
2015-12-01
The purpose was to compare the effect of the repeated usage of two care systems (one hydrogen peroxide cleaning and disinfecting system and one polyaminopropyl biguanide (PHMB) containing multi-purpose system) with silicone hydrogel contact lenses worn for three months on a daily wear modality. A specific aspect of interest was of the effect of the care systems on contact lens wettability. Seventy-four symptomatic contact lens wearers, habitually wearing either ACUVUE(®) OASYS(®) (n=37) or PureVision™ (n=37), constituted the study population. The study was a two-arm prospective, investigator-masked, bilateral study of three-month duration to evaluate the effects of CLEAR CARE(®) compared with renu(®) fresh™. The subjects were randomized to one of the two lens care systems. Contact lens wettability and surface cleanliness were assessed with the Tearscope and reported in terms of pre-lens non-invasive break-up time (PL-NIBUT) and visible deposits. Baseline assessments at enrollment were with the subjects' own contact lenses worn for at least 6h when using their habitual PHMB-preserved care system and at the dispensing visit with new contact lenses. At the follow-up visits, the contact lenses were worn for at least 6h, and were at least 11 days old for ACUVUE(®) OASYS(®) and 25 days old for PureVision™. The results obtained showed that: (i) with CLEAR CARE(®), a significant improvement in contact lens wettability was recorded compared with the habitual care system at the three-month follow-up visit (mean median PL-NIBUT 5.8 vs. 4.0 s, p<0.001). Further, with this same lens care system a significant increase in wettability was observed at the three-month follow-up visit compared with dispensing (mean median PL-NIBUT 5.8 vs. 4.5s, p=0.022). (ii) Whereas no difference in contact lens wettability was observed at dispensing between the two lens care groups (mean PL-NIBUT: 4.5 vs. 4.2s, p=0.518), a significantly more stable pre-lens tear film was observed with CLEAR CARE(®) than with renu(®) fresh™ at both the two-month (mean PL-NIBUT: 4.6 vs. 3.7s, p=0.005) and three-month (mean PL-NIBUT: 5.8 vs. 4.2 s, p=0.028) visits. iii. With renu(®) fresh™, no significant differences were observed at the end of three months of use compared with either the habitual care system or the new contact lens solution (mean PL-NIBUT: 3M 4.2 vs. Disp 4.2 s (p=0.420) vs. enrolment habitual care solution 5.1s (p=0.734)). iv. With CLEAR CARE(®) significant increases in the incidence of surfaces free of both mucus (3 month 95%. vs. habitual solution 82% enrolment; p=0.005) and lipid (3 month 87% vs. habitual solution 72% enrolment; p=0.009) were observed. Significantly better contact lens wettability and surface cleanliness were achieved for ACUVUE(®) OASYS(®) and PureVision™ with CLEAR CARE(®) than with renu(®) fresh™ at the end of three months of use. Copyright © 2015. Published by Elsevier Ltd.
Nandyal, C B; Sutrave, Mithun; Kurle, Vinayak; Harsoor, Pallavi A
2018-03-01
To study functional outcome of the endoscopic management of limited attico-antral cholesteatoma in terms of visualization of sac, cholesteatoma disease clearance, ABG closure improvement, preservation of residual anatomy and recurrence of disease. It is a prospective study done during Feb 2016 to March 2017 done on 20 pts with limited attico-antral cholesteatoma with CT confirmation. Endoscopic management of limited attico-antral cholesteatoma with complete removal of sac, infected discharge and granulations along with creation of MRMC Neo surgical ventilating port (joining Anterior & posterior isthmuses) done in cases where residual attic anatomy was present to establish physiological attic ventilation and drainage. Whereas in cases of attic and ossicular erosion, ossiculoplasty along with neo attic malleo-incudal complex (with composite tragal cartilage with perichondrium graft) for lateral attic wall reconstruction was done to prevent attic retraction. Patients had mean pre op ABG of 36.29 ± 6.29 and mean post op ABG closure of 16.33 ± 6.50 with no recurrence of cholesteatoma at 6 months of follow up. Patient showed significant (55%) improvement in hearing with all having graft uptake in which four cases having mild pars tensa retraction which recovered later without any intervention. Thus creation of new MRMC Neo surgical ventilating port or neo attic malleo-incudal complex with endoscopic approach allows better visual access to clear the limited attico-antral disease with sparing of normal residual attic anatomy along with physiological ventilation and drainage having better hearing results and outcome.
Vitrectomy for primary symptomatic vitreous opacities: an evidence-based review
Ivanova, T; Jalil, A; Antoniou, Y; Bishop, P N; Vallejo-Garcia, J L; Patton, N
2016-01-01
Floaters are a common ocular condition which form as a consequence of aging changes in the vitreous. Although in most patients the symptoms are minimal, they can cause significant impairment in vision-related quality of life in a small population of patients. Recently there has been an increase in awareness of the visual disability caused by floaters, and the evidence-base for treatment of this condition using small-gauge vitrectomy has increased. In this review, we define the term ‘floaters' as symptomatic vitreous opacities (SVO). We suggest a classification dependent on the presence or absence of posterior vitreous detachment and discuss their pathogenesis and natural history. We review their impact on patients' quality of life related to visual function. We review the psychological factors that may have a role in some patients who appear to be affected by SVO to the extent that they pursue all options including surgery with all its attendant risks. We summarise the available evidence-base of treatment options available for SVO with special emphasis on the safety and efficacy of vitrectomy for this condition. PMID:26939559
Changing Trends in Surgery for Retinal Detachment in Korea
Cho, Ga Eun; Kim, Seong Wook
2014-01-01
Purpose To analyze trends in rhegmatogenous retinal detachment (RRD) surgery among the members of the Korean Retina Society from 2001 to 2013. Methods In 2013, surveys were conducted by email and post to investigate the current practice patterns regarding RRD treatment. Questions included how surgeons would manage six cases of hypothetical RRD. Results were compared to those reported in 2001. Results A total of 133 members (60.7%) in 2013 and 46 members(79.3%) in 2001 responded to the survey. Preference for pneumatic retinopexy has decreased in uncomplicated primary RRD (p = 0.004). More respondents in 2013 selected vitrectomy as the primary procedure when mild vitreous hemorrhage (p = 0.001), myopia (p = 0.044) and history of successful scleral buckling on the fellow eye (p = 0.044) were added to the primary scenario. Vitrectomy was over twice as popular in cases of pseudophakic, macula-off RRD with posterior capsular opacity (p = 0.001). Conclusions For RRD with myopia, pseudophakia and media opacity, surgical interventions over the last decade have drastically shifted from scleral buckling and pneumatic retinopexy to vitrectomy. PMID:25435747
In-cylinder air-flow characteristics of different intake port geometries using tomographic PIV
NASA Astrophysics Data System (ADS)
Agarwal, Avinash Kumar; Gadekar, Suresh; Singh, Akhilendra Pratap
2017-09-01
For improving the in-cylinder flow characteristics of intake air/charge and for strengthening the turbulence intensity, specific intake port geometries have shown significant potential in compression ignition engines. In this experimental study, effects of intake port geometries on air-flow characteristics were investigated using tomographic particle imaging velocimetry (TPIV). Experiments were performed using three experimental conditions, namely, swirl port open (SPO), tangential port open (TPO), and both port open (BPO) configurations in a single cylinder optical research engine. Flow investigations were carried out in a volumetric section located in the middle of the intake and exhaust valves. Particle imaging velocimetry (PIV) images were captured using two high speed cameras at a crank angle resolution of 2° in the intake and compression strokes. The captured PIV images were then pre-processed and post-processed to obtain the final air-flow-field. Effects of these two intake ports on flow-field are presented for air velocity, vorticity, average absolute velocity, and turbulent kinetic energy. Analysis of these flow-fields suggests the dominating nature of the swirl port over the tangential port for the BPO configuration and higher rate of flow energy dissipation for the TPO configuration compared to the SPO and BPO configurations. These findings of TPIV investigations were experimentally verified by combustion and particulate characteristics of the test engine in thermal cylinder head configuration. Combustion results showed that the SPO configuration resulted in superior combustion amongst all three port configurations. Particulate characteristics showed that the TPO configuration resulted in higher particulate compared to other port configurations.
Warren, Adam; Bell, Morag; Budd, Lucy
2012-01-01
The liberalisation of the European aviation sector has multiplied paths of entry into the United Kingdom (UK) for the international traveller. These changing mobilities necessitate a reconceptualisation of the border as a series of potentially vulnerable nodes occurring within, and extending beyond, national boundaries. In this paper, we consider the border through the lens of port health, the collective term for various sanitary operations enacted at international transport terminals. In the UK, a critical player in the oversight of port health is the Health Protection Agency (HPA), which became a non-Departmental public body in 2005. A major part of port health is preparedness, a set of techniques aimed at managing, and responding to, emergencies of public health concern. More recently, certain jurisdictions have embarked on public health preparedness work across a number of different geographical scales. Using methods pioneered by the military, this form of 'distributed preparedness' is of increased interest to social science and medical scholars. With reference to case studies conducted in localities surrounding two UK regional airports following the 2009-10 H1N1 influenza pandemic, we consider the extent to which distributed preparedness as a concept and a set of practices can inform current debates - in the UK, and beyond - concerning interventions at the border 'within'. Copyright © 2011 Elsevier Ltd. All rights reserved.
Enhanced methodology for porting ion chromatography retention data.
Park, Soo Hyun; Shellie, Robert A; Dicinoski, Greg W; Schuster, Georg; Talebi, Mohammad; Haddad, Paul R; Szucs, Roman; Dolan, John W; Pohl, Christopher A
2016-03-04
Porting is a powerful methodology to recalibrate an existing database of ion chromatography (IC) retention times by reflecting the changes of column behavior resulting from either batch-to-batch variability in the production of the column or the manufacture of new versions of a column. This approach has been employed to update extensive databases of retention data of inorganic and organic anions forming part of the "Virtual Column" software marketed by Thermo Fisher Scientific, which is the only available commercial optimization tool for IC separation. The current porting process is accomplished by performing three isocratic separations with two representative analyte ions in order to derive a porting equation which expresses the relationship between old and new data. Although the accuracy of retention prediction is generally enhanced on new columns, errors were observed on some columns. In this work, the porting methodology was modified in order to address this issue, where the porting equation is now derived by using six representative analyte ions (chloride, bromide, iodide, perchlorate, sulfate, and thiosulfate). Additionally, the updated porting methodology has been applied on three Thermo Fisher Scientific columns (AS20, AS19, and AS11HC). The proposed approach showed that the new porting methodology can provide more accurate and robust retention prediction on a wide range of columns, where average errors in retention times for ten test anions under three eluent conditions were less than 1.5%. Moreover, the retention prediction using this new approach provided an acceptable level of accuracy on a used column exhibiting changes in ion-exchange capacity. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.
Trocar Port Hernias After Bariatric Surgery.
Coblijn, Usha K; de Raaff, Christel A L; van Wagensveld, Bart A; van Tets, Willem F; de Castro, Steve M M
2016-03-01
Laparoscopic bariatric surgery is increasingly being performed worldwide. It is estimated that trocar port hernias occur more often in obese patients due to their obesity and because the ports are not closed routinely. The aim of the present study was to analyze the incidence, risk factors, and management of patients with trocar port hernias after laparoscopic bariatric surgery. All patients who were operated between 2006 and 2013 were included. During the study period, the trocar ports were not closed routinely. All patients who had any symptomatic abdominal wall hernia during follow-up were included. Overall, 1524 laparoscopic bariatric procedures were performed. There were 1249 female (82 %) and 275 male (18 %) patients. The mean age was 44 years, and median body mass index was 43 kg/m(2). Patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB) (n = 859), laparoscopic adjustable gastric banding (LAGB) (n = 364), laparoscopic sleeve gastrectomy (LSG) (n = 68), revisional surgery (n = 226), and other procedures (n = 7). Three hundred and one patients (20 %) had one or more postoperative complications and the overall mortality was 0.3 % (four patients). There were 14 patients (0.9 %) with an abdominal wall hernia, of which eight (0.5 %) had a trocar port hernia, three (0.2 %) an incisional hernia from other previous surgery, and three (0.2 %) an umbilical hernia. Gender, age, BMI, smoking, type II diabetes, procedure type, complications, and weight loss were not associated with the occurrence of abdominal wall hernias. Trocar port hernias after bariatric surgery occur seldom if the trocar port is not routinely closed.
Son, Gisung; Lee, Ji Shin; Lee, Suchan; Sohn, Joonhong
2016-12-01
To discuss the unique morphology and origin of epiretinal proliferation associated with macular hole (EPMH) occasionally observed in full-thickness macular hole (FT-MH) or lamellar hole (LH) and to introduce the perifoveal crown phenomenon encountered when removing this unusual proliferative tissue. Sixteen patients showing EPMH in spectral domain-optical coherence tomography were selected from 212 patients diagnosed with MH, LH, FT-MH, impending MH, macular pseudohole, or epiretinal membrane between January 2013 and December 2014. Of the 212 patients included for clinical analysis, 33, 23, 11, 7, and 190 exhibited LH, FT-MH, impending MH, macular pseudohole, and epiretinal membrane, respectively. We reviewed visual acuity, macular morphology, and clinical course. Surgical specimens were analyzed histologically. EPMH presented as an amorphous proliferation starting from the defective inner/outer segment (IS/OS) junction covering the inner macula surface. Among the 16 patients with EPMH, 11 underwent vitrectomy, and all exhibited the intraoperative perifoveal crown phenomenon. EPMH tissue was sampled in three patients, one of whom had more tissue removed than intended and showed delayed recovery in visual acuity. Despite hole closure, IS/OS junction integrity was not successfully restored in four of 11 patients. Five patients were followed-up without surgical intervention. Visual acuity slightly decreased in three patients and did not change in one patient, while the remaining patient was lost during follow-up. Among the three perifoveal crown tissues obtained, two were successfully analyzed histologically. Neither tissue showed positivity to synaptophysin or S-100 protein, but one showed positivity to cytokeratin protein immunohistochemical staining. EPMH exhibited a distinct but common configuration in spectral domain-optical coherence tomography. An epithelial proliferation origin is plausible based on its configuration and histological analysis. Perifoveal crown phenomenon was observed when removing EPMH during vitrectomy.
Boost, Maureen V; Cho, Pauline
2005-06-01
The purpose of this study is to determine if there are changes in the ocular flora of overnight orthokeratology (ortho-k) patients, and the levels of contamination of their lenses and lens accessories, and to correlate compliance with levels of contamination. Normal ocular flora of 41 subjects was determined twice before commencing ortho-k lens wear by culture of the lower conjunctiva. Further specimens were collected on six follow-up visits after beginning lens wear, as were samples from their lenses, cases, and suction holders. A questionnaire on lens care was administered after the fifth visit. Three subjects provided conjunctival samples yielding Staphylococcus aureus on one occasion before lens wear, one being positive for this organism after beginning lens wear. Of 38 subjects yielding no growth or only normal eye flora before use, 28 remained free of ocular pathogens after beginning lens wear. Only four subjects had positive cultures on more than one occasion after lens wear. There was no significant difference in isolation levels of pathogens with lens wear (p = 0.423). Lens culture of 54% of subjects yielded no growth or normal flora only; lenses of 16 subjects yielded potential pathogens, including three subjects contaminated on more than one occasion. Lens isolates did not match the organisms transiently colonizing the eye. Lens case, the most frequently contaminated item, was associated with lens contamination (p < 0.001), the same organism being isolated from both items in 11 subjects. Lens suction holder was less frequently contaminated. Neither lens case nor suction holder contamination was associated with isolates from the eye. Reported good compliance correlated with lack of contamination in all but one subject. The most frequent breaches in the lens care protocol were failure to clean, disinfect, and replace the lens case. Ocular flora was not altered by ortho-k lens wear over an extended period, and patients remained free of infection. Contaminants identified were generally of a transient nature. Most patients had significant contamination of at least one item, most frequently the lens case. Lens case isolates were significantly associated with those from the lens. The majority of patients reporting good compliance had low or no contamination of their lenses and accessories.
Comparison of OVD and BSS for Maintaining the Anterior Chamber during IOL Implantation
Lee, Ho Young; Choy, Yoon Jung
2011-01-01
Purpose To compare surgical results between conventional intraocular lens (IOL) implantation using an ophthalmic viscosurgical device (OVD) and IOL implantation using a balanced salt solution (BSS) after irrigation/aspiration (I/A) of the lens cortex. Methods A randomized prospective study was conducted on 62 patients who underwent cataract surgery. Following completion of conventional I/A of the lens cortex, we divided patients into two groups according to whether or not BSS was used. In group A (n = 31), the anterior chamber and the capsular bag were completely filled with an OVD before IOL implantation. On the other hand, in group B (n = 31), BSS was irrigated into the anterior chamber through a previous side port during IOL implantation. Surgical results were compared between the two groups. Results In both groups, IOP peaked six hours after surgery. The occurrence of an IOP spike by postoperative day one was observed in six cases (6 / 31) in group A and in no cases (0 / 31) in group B, a difference that was statistically significant (p = 0.024). The values of endothelial cell density, central corneal thickness, anterior chamber inflammation, myopic shift, and posterior capsule opacification were not significantly different between the two groups. Conclusions Compared with the use of OVD for IOL implantation, use of BSS during IOL implantation resulted in reductions in postoperative IOP spike and OVD removal time. PMID:21350689
Biswas, Partha; Gogate, Parikshit Madhav; Maskati, Quresh Badr; Natarajan, Sundaram; Verma, Lalit; Bansal, Payal K
2018-06-01
To gauge the differences in ophthalmology residency training, academic, clinical and surgical, in the last three decades of the 20 th century and the first decade of the 21 st century. A survey was conducted by the Academic and Research Committee of the All India Ophthalmological Society, in 2014-2016, using a prevalidated questionnaire, which was circulated to ophthalmologists to gauge the practicality of the teaching protocols of clinical and surgical skills during postgraduate residency program. Of the 1005 respondents, 320 ophthalmologists who completed residency between 1967 and 2002 (20 th century trained) and 531 who completed a residency in 2003-2012 (21 st century trained) fulfilled the inclusion criteria. The average age was 49.2 years (standard deviation [SD] 4) and 32.6 years (SD 4), respectively. Twenty-first century trained ophthalmologists rated their training significantly better than the 20 th century trained ophthalmologists for slit lamp examination (P = 0.001), indirect ophthalmoscopy, gonioscopy, automated perimetry, optical coherence tomography, and fundus photography (all having P < 0.001), while the 20 th century trained rated their teaching of refraction, synoptophore, diplopia charting better (all P < 0.001). The range of grading was 0-10 in all categories. The median number of surgeries performed independently by 20 th century and 21 st century trained (during their training period) were: intracapsular cataract extraction (ICCE) 10, 0; extracapsular cataract extraction (ECCE) 43, 18; small incision cataract surgery (SICS) 5, 55; phacoemulsification (Phaco) 0, 1; pterygium excision 20, 15; dacryocystectomy 11, 4; dacryocystorhinostomy 11, 2; chalazion 35, 30; trabeculectomies 5, 0; strabismus correction 0, 0; vitrectomy 0, 0; keratoplasty 0, 0; eyelid surgery 6, 2; and ocular emergencies 18, 20. Teaching of many clinical skills had improved over decades. Cataract surgery training has shifted from ICCE and ECCE to SICS and Phaco, but other surgeries were still taught sparingly. There was an enormous variation across the country in residency training which needs immediate attention.
Inflammation and Macular Oedema after Pars Plana Vitrectomy
Romano, Vito; Angi, Martina; del Grosso, Renata; Romano, Davide; Vinciguerra, Paolo; Romano, Mario R.
2013-01-01
Cystoid macular oedema (CMO) is a major cause of reduced vision following intraocular surgery. Although the aetiology of CMO is not completely clarified, intraocular inflammation is known to play a major role in its development. The macula may develop cytotoxic oedema when the primary lesion and fluid accumulation occur in the parenchymatous cells (intracellular oedema) or vasogenic oedema when the primary defect occurs in the blood-retinal barrier and leads to extracellular fluid accumulation (extracellular oedema). We report on the mechanisms of CMO formation after pars plana vitrectomy and associated surgical procedures and discuss possible therapeutic approaches. PMID:24288446
OCT-based full crystalline lens shape change during accommodation in vivo.
Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana
2017-02-01
The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic.
OCT-based full crystalline lens shape change during accommodation in vivo
Martinez-Enriquez, Eduardo; Pérez-Merino, Pablo; Velasco-Ocana, Miriam; Marcos, Susana
2017-01-01
The full shape of the accommodating crystalline lens was estimated using custom three-dimensional (3-D) spectral OCT and image processing algorithms. Automatic segmentation and distortion correction were used to construct 3-D models of the lens region visible through the pupil. The lens peripheral region was estimated with a trained and validated parametric model. Nineteen young eyes were measured at 0-6 D accommodative demands in 1.5 D steps. Lens volume, surface area, diameter, and equatorial plane position were automatically quantified. Lens diameter & surface area correlated negatively and equatorial plane position positively with accommodation response. Lens volume remained constant and surface area decreased with accommodation, indicating that the lens material is incompressible and the capsular bag elastic. PMID:28270993
Testing and Analysis of Sensor Ports
NASA Technical Reports Server (NTRS)
Zhang, M.; Frendi, A.; Thompson, W.; Casiano, M. J.
2016-01-01
This Technical Publication summarizes the work focused on the testing and analysis of sensor ports. The tasks under this contract were divided into three areas: (1) Development of an Analytical Model, (2) Conducting a Set of Experiments, and (3) Obtaining Computational Solutions. Results from the experiment using both short and long sensor ports were obtained using harmonic, random, and frequency sweep plane acoustic waves. An amplification factor of the pressure signal between the port inlet and the back of the port is obtained and compared to models. Comparisons of model and experimental results showed very good agreement.
2. AERIAL VIEW EXUSS HORNET CVS12 LOOKING PORT TO STARBOARD, ...
2. AERIAL VIEW EX-USS HORNET CVS-12 LOOKING PORT TO STARBOARD, THREE MINECRAFT MORRED ALONGSIDE ON PORT AFT QUARTER. OTHER INACTIVE SHIPS IN BACKGROUND, PUGET SOUND NAVEL SHIPYARD TO LEFT SIDE OF PHOTO. - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA
Performance of Three Multipurpose Disinfecting Solutions with a Silicone Hydrogel Contact Lens
García-Porta, Nery; Rico-del-Viejo, Laura; Ferreira-Neves, Helena; Peixoto-de-Matos, Sofia C.; Queirós, Antonio; González-Méijome, José M.
2015-01-01
Purpose. To evaluate the clinical performance of a silicone hydrogel (Si-Hy) soft contact lens (CL) in combination with three different multipurpose disinfecting solutions (MPDSs). Methods. This was a prospective, randomized, single-masked, crossover, and comparative study in which 31 habitual soft CL wearers were randomly assigned to one of the three MPDSs (Synergi, COMPLETE RevitaLens, and OPTI-FREE PureMoist) for 1 month with a 1-week wash-out period between each exposure. All subjects were successfully refitted with a Si-Hy CL (Biofinity). Subjects were then scheduled for follow-up visits after 1 month of lens wear, being evaluated at 2 and 8 hours after lens insertion. Visual Analogue Scales (VAS) were used to gauge comfort rating. Results. The tarsal conjunctiva showed a significantly different degree of lid redness between the MPDSs at the 2-hour visit (P < 0.05, Kruskal-Wallis test), being lower for COMPLETE RevitaLens compared to the other two MPDSs (Mann-Whitney U test). Furthermore, a significantly different degree of lid roughness at the 8-hour visit was seen (P < 0.05, Kruskal-Wallis test), being higher for Synergi (Mann-Whitney U test). The subjective comfort was similar with the three MPDSs. Conclusion. Tarsal conjunctival response should be also considered in the context of the clinical performance of MPDs at the ocular surface. PMID:25918703
Parenchymal-sparing hepatectomy for deep-placed colorectal liver metastases.
Matsuki, Ryota; Mise, Yoshihiro; Saiura, Akio; Inoue, Yosuke; Ishizawa, Takeaki; Takahashi, Yu
2016-11-01
The feasibility of parenchymal-sparing hepatectomy has yet to be assessed based on the tumor location, which affects the choice of treatment in patients with colorectal liver metastases. Sixty-three patients underwent first curative hepatectomy for deep-placed colorectal liver metastases whose center was located >30 mm from the liver surface. Operative outcomes were compared among patients who underwent parenchymal-sparing hepatectomy or major hepatectomy (≥3 segments). Parenchymal-sparing hepatectomy and major hepatectomy were performed for deep-placed colorectal liver metastases in 40 (63%) and 23 (37%) patients, respectively. Resection time was longer in the parenchymal-sparing hepatectomy than in the major hepatectomy group (57 vs 39 minutes) (P = .02) and cut-surface area was wider (120 vs 86 cm 2 ) (P < .01). Resected volume was smaller in the parenchymal-sparing hepatectomy than in the major hepatectomy group (251 vs 560 g) (P < .01). No differences were found between the 2 groups for total operation time (306 vs 328 minutes), amount of blood loss (516 vs 400 mL), rate of major complications (10% vs 13%), and positive operative margins (5% vs 4%). Overall, recurrence-free, and liver recurrence-free survivals did not differ between the 2 groups. Direct major hepatectomy without portal venous embolization could not have been performed in 40% of the parenchymal-sparing hepatectomy group (16/40) because of the small liver remnant volume. Parenchymal-sparing hepatectomy for deep-placed colorectal liver metastases was performed safely without compromising oncologic radicality. Parenchymal-sparing hepatectomy can increase the number of patients eligible for an operation by halving the resection volume and by increasing the chance of direct operative treatment in patients with ill-located colorectal liver metastases. Copyright © 2016 Elsevier Inc. All rights reserved.
Nakamura, Kenta; Tsonis, Panagiotis A.
2014-01-01
Adult newts (Notophthalmus viridescens) are capable of complete lens regeneration that is mediated through dorsal iris pigment epithelial (IPE) cells transdifferentiation. In contrast, higher vertebrates such as mice demonstrate only limited lens regeneration in the presence of an intact lens capsule with remaining lens epithelial cells. To compare the intrinsic lens regeneration potential of newt IPE versus mouse lens epithelial cells (MLE), we have established a novel culture method that uses cell aggregation before culture in growth factor-reduced Matrigel™. Dorsal newt IPE aggregates demonstrated complete lens formation within 1 to 2 weeks of Matrigel culture without basic fibroblast growth factor (bFGF) supplementation, including the establishment of a peripheral cuboidal epithelial cell layer, and the appearance of central lens fibers that were positive for αA-crystallin. In contrast, the lens-forming potential of MLE cell aggregates cultured in Matrigel was incomplete and resulted in the formation of defined-size lentoids with partial optical transparency. While the peripheral cell layers of MLE aggregates were nucleated, cells in the center of aggregates demonstrated a nonapoptotic nuclear loss over a time period of 3 weeks that was representative of lens fiber formation. Matrigel culture supplementation with bFGF resulted in higher transparent bigger-size MLE aggregates that demonstrated increased appearance of βB1-crystallin expression. Our study demonstrates that bFGF is not required for induction of newt IPE aggregate-dependent lens formation in Matrigel, while the addition of bFGF seems to be beneficial for the formation of MLE aggregate-derived lens-like structures. In conclusion, the three-dimensional aggregate culture of IPE and MLE in Matrigel allows to a higher extent than older models the indepth study of the intrinsic lens-forming potential and the corresponding identification of lentogenic factors. PMID:23672748
Slow Controls Using the Axiom M5235BCC
NASA Astrophysics Data System (ADS)
Hague, Tyler
2008-10-01
The Forward Vertex Detector group at PHENIX plans to adopt the Axiom M5235 Business Card Controller for use as slow controls. It is also being evaluated for slow controls on FermiLab e906. This controller features the Freescale MCF5235 microprocessor. It also has three parallel buses, these being the MCU port, BUS port, and enhanced Time Processing Unit (eTPU) port. The BUS port uses a chip select module with three external chip selects to communicate with peripherals. This will be used to communicate with and configure Field Programmable Gate Arrays (FPGAs). The controller also has an Ethernet port which can use several different protocols such as TCP and UDP. This will be used to transfer files with computers on a network. The M5235 Business Card Controller will be placed in a VME crate along with VME card and a Spartan-3 FPGA.
2001-08-06
KENNEDY SPACE CENTER, Fla. -- On Launch Pad 39A, workers check out the loading of the payloads into Discovery’s payload bay. In the center is the Multi-Purpose Logistics Module Leonardo, filled with laboratory racks of science equipment and racks and platforms of experiments and supplies. Above Leonardo is the Integrated Cargo Carrier with the Early Ammonia Servicer (EAS) in the center. The EAS contains spare ammonia for the Station’s cooling system. Ammonia is the fluid used in the radiators that cool the Station’s electronics. The EAS will be installed on the P6 truss holding the giant U.S. solar arrays, batteries and cooling radiators. Seen below the MPLM and attached on the port and starboard adapter beams are experiments. Discovery is scheduled to be launched Aug. 9, 2001
Liu, Li-Ping; Dong, Bao-Wei; Yu, Xiao-Ling; Zhang, Da-Kun; Li, Xin; Li, Hua
2008-03-01
The purpose of this study was to investigate whether focal fatty sparing (FFS) formation in the liver relates to aberrant blood flow. Sixty-three FFSs of the liver in 52 patients were examined by color Doppler flow imaging and contrast-enhanced microvessel display sonography. The 63 FFSs included 16 FFSs in the porta hepatis, 14 FFSs around the gallbladder fossa, and 33 other FFSs. The control group included patients with a diagnosis of fatty liver but no FFSs or focal lesions near the porta hepatis. Fourteen of 16 FFSs in the porta hepatis showed venous blood toward those areas that were differentiated from the portal and hepatic veins. Focal fatty sparings in the hilus hepatis correlated with aberrant veins, having a statistical significance compared with the control group (P < .0001). Seven of 14 FFSs around the gallbladder fossa contained blood vessels, 5 of them veins and the remaining 2 arteries. Two FFSs were located around hemangiomas. Three FFSs were located around maldeveloped vessels. The blood supply to an FFS in the porta hepatis may be correlated with aberrant veins. Focal fatty sparings around the gallbladder fossa may be associated with aberrant blood flow.
Analysis of crystalline lens coloration using a black and white charge-coupled device camera.
Sakamoto, Y; Sasaki, K; Kojima, M
1994-01-01
To analyze lens coloration in vivo, we used a new type of Scheimpflug camera that is a black and white type of charge-coupled device (CCD) camera. A new methodology was proposed. Scheimpflug images of the lens were taken three times through red (R), green (G), and blue (B) filters, respectively. Three images corresponding with the R, G, and B channels were combined into one image on the cathode-ray tube (CRT) display. The spectral transmittance of the tricolor filters and the spectral sensitivity of the CCD camera were used to correct the scattering-light intensity of each image. Coloration of the lens was expressed on a CIE standard chromaticity diagram. The lens coloration of seven eyes analyzed by this method showed values almost the same as those obtained by the previous method using color film.
Water quality assessment of Australian ports using water quality evaluation indices
Jahan, Sayka
2017-01-01
Australian ports serve diverse and extensive activities, such as shipping, tourism and fisheries, which may all impact the quality of port water. In this work water quality monitoring at different ports using a range of water quality evaluation indices was applied to assess the port water quality. Seawater samples at 30 stations in the year 2016–2017 from six ports in NSW, Australia, namely Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden, were investigated to determine the physicochemical and biological variables that affect the port water quality. The large datasets obtained were designed to determine the Water Quality Index, Heavy metal Evaluation Index, Contamination Index and newly developed Environmental Water Quality Index. The study revealed medium water quality index and high and medium heavy metal evaluation index at three of the study ports and high contamination index in almost all study ports. Low level dissolved oxygen and higher level of total dissolved solids, turbidity, fecal coliforms, copper, iron, lead, zinc, manganese, cadmium and cobalt are mainly responsible for the poor water qualities of the port areas. Good water quality at the background samples indicated that various port activities are the likely cause for poor water quality inside the port area. PMID:29244876
Glare effect for three types of street lamps based on White LEDs
NASA Astrophysics Data System (ADS)
Sun, Ching-Cherng; Jiang, Chong-Jhih; Chen, Yi-Chun; Yang, Tsung-Hsun
2014-05-01
This study is aimed to assess the glare effect from LED-based street lamps with three general optical designs, which are cluster LEDs with a single lens, a LED array accompany with a lens array, and a tilted LED array, respectively. Observation conditions were simulated based on various locations and viewing axes. Equivalent luminance calculations were used to reveal the glare levels of the three designs. The age effect for the calculated equivalent luminance was also examined for human eyes of people at the age of 40 or 60. The results demonstrate that among the three design types, a LED array accompany with a lens array causes relatively smaller glare for most viewing conditions.
Heterochromatic Flicker Photometry for Objective Lens Density Quantification.
Najjar, Raymond P; Teikari, Petteri; Cornut, Pierre-Loïc; Knoblauch, Kenneth; Cooper, Howard M; Gronfier, Claude
2016-03-01
Although several methods have been proposed to evaluate lens transmittance, to date there is no consensual in vivo approach in clinical practice. The aim of this study was to compare ocular lens density and transmittance measurements obtained by an improved psychophysical scotopic heterochromatic flicker photometry (sHFP) technique to the results obtained by three other measures: a psychophysical threshold technique, a Scheimpflug imaging technique, and a clinical assessment using a validated subjective scale. Forty-three subjects (18 young, 9 middle aged, and 16 older) were included in the study. Individual lens densities were measured and transmittance curves were derived from sHFP indexes. Ocular lens densities were compared across methods by using linear regression analysis. The four approaches showed a quadratic increase in lens opacification with age. The sHFP technique revealed that transmittance decreased with age over the entire visual spectrum. This decrease was particularly pronounced between young and older participants in the short (53.03% decrease in the 400-500 nm range) wavelength regions of the light spectrum. Lens density derived from sHFP highly correlated with the values obtained with the other approaches. Compared to other objective measures, sHFP also showed the lowest variability and the best fit with a quadratic trend (r2 = 0.71) of lens density increase as a function of age. The sHFP technique offers a practical, reliable, and accurate method to measure lens density in vivo and predict lens transmittance over the visible spectrum. An accurate quantification of lens transmittance should be obtained in clinical practice, but also in research in visual and nonvisual photoreception.
Pars plana vitrectomy for visually disturbing vitreous floaters in pseudophacic eyes.
Stoffelns, B M; Vetter, J; Keicher, A; Mirshahi, A
2011-04-01
The aim of this study was to evaluate the role of vitrectomy in patients with visually disturbing vitreous opacities. A retrospective analysis of the patient characteristics and the outcome of all pseudophacic eyes, which consecutively received in the decade 1996 to 2005 20 G pars plana vitrectomy for visually disturbing floaters, was carried out at the Mainz University Eye Clinic. Forty-one eyes of 32 patients (63 % university graduates, median age: 64 years) were included in the study. The mean axial length of the globe was 25.3 mm (range: 22.8 to 28.9 mm). Additional pathologies having influence on the vitreous condition were history of laser or cryo retinopexy (12 ×), buckle surgery (5 ×), complicated cataract surgery (16 ×) and Nd:YAG laser capsulotomy (4 ×). Vitreous floaters were considered to be the result of posterior vitreous detachment alone in 61 %, of asteroid hyalosis accompanied by posterior vitreous detachment in 17 %, and vitreous syneresis in 15 % of the eyes. Intraoperatively retinopexy with endolaser or cryo was performed in 6 % of cases. A secondary retinal detachment occurred in one eye (2 %). Thirty-one of 32 patients reported to be very satisfied with the postoperative result. Objectively, their visual acuity was better than or equal to preoperative acuity in 95 % of the eyes. Pars plana vitrectomy provides a highly effective treatment for visually disturbing vitreous floaters. In an era in which the expectations and demands of individuals on the quality of vision and life have increased significantly, with careful case selection the benefits of the surgical intervention may outweigh the surgical risks. © Georg Thieme Verlag KG Stuttgart · New York.
Takamura, Yoshihiro; Shimura, Masahiko; Katome, Takashi; Someya, Hideaki; Sugimoto, Masahiko; Hirano, Takao; Sakamoto, Taiji; Gozawa, Makoto; Matsumura, Takehiro; Inatani, Masaru
2018-01-17
To investigate whether intravitreal injection of triamcinolone acetonide (IVTA) combined with vitrectomy prevents postoperative inflammation in patients with vitreous haemorrhage (VH) due to proliferative diabetic retinopathy (PDR). This prospective, multicentre, randomised study conducted at seven sites in Japan enrolled patients diagnosed as having VH following PDR. Patients underwent vitrectomy with (IVTA+VIT group) or without (VIT group) IVTA at the end of the surgery. Anterior flare intensity (AFI), central retinal thickness (CRT), best-corrected visual acuity (BCVA) and intraocular pressure (IOP) were measured before and at 3 days, 1 week, 1, 3 and 6 months after surgery and compared. Number of patients who completed 6 months of follow-up was 40 and 41 in VIT group and IVTA+VIT group, respectively. AFI was significantly higher in the VIT group than in the IVTA+VIT group at 3 days (P=0.033), 1 week (P=0.019) and 1 month (P=0.037). There were no significant differences in CRT, BCVA and IOP between the groups through the observational periods. In the cases with macular oedema >350 µm of CRT at 3 days, CRT was significantly lower in the IVTA+VIT group than in the VIT group at 1 month (P=0.041). IVTA combined with vitrectomy and cataract surgery contributed to inhibit the postoperative inflammation in patients with VH due to PDR. The effect of IVTA in the reduction of diabetic macular oedema may be limited to the early stage after surgery. UMIN000020376, Post-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Vitrectomy for optic disk pit with macular schisis and outer retinal dehiscence.
Shukla, Dhananjay; Kalliath, Jay; Tandon, Manish; Vijayakumar, Balakrishnan
2012-07-01
To describe the outcomes of vitrectomy for optic disc pit-related maculopathy with central outer retinal dehiscence. This prospective interventional case series included seven patients with optic disc pit with macular schisis and central outer retinal dehiscence who underwent vitrectomy with internal limiting membrane peeling, barrage laser photocoagulation, and gas tamponade and were followed for at least 6 months. The surgical outcomes in terms of restoration of macular anatomy and visual improvement were recorded at each visit by fundus photography and optical coherence tomography. The mean age of the patients was 21.3 ± 8.6 years (range, 10-35 years), and the mean duration of defective vision was 6.7 ± 8.5 months (range, 1-24 months). Preoperatively, the median best-corrected visual acuity (BCVA) was 20/60 (range, 20/40 to 20/120). Full-thickness macular holes were noticed in 4 patients 1 month postoperatively. Gas tamponade was repeated in two patients with large macular holes. By the final follow-up, macular holes had closed and BCVA improved in all patients except one. Final mean central macular thickness was 176.83 ± 55.74 μ, the range being 109 μ to 256 μ. The median postoperative BCVA was 20/30 (range, 20/20 to 20/80). Six of 7 patients (85.7%) had improvement in BCVA postoperatively (mean, +2 lines; range, 1-4 lines). Five patients (71%) achieved a postoperative BCVA of ≥20/30. Best-corrected visual acuity dropped by one line in the patient with persistent macular hole. Vitrectomy with internal limiting membrane peeling can achieve excellent final surgical outcomes in optic pit maculopathy with outer retinal dehiscence despite the potential for macular hole formation.
Wei, Yong; Wang, Ningli; Zu, Zhongqiao; Bi, Chuncao; Wang, Huaizhou; Chen, Fenghua; Yang, Xingguang
2013-06-01
To compare the outcomes of pars plana vitrectomy (PPV) with or without the adjuvant surgical procedures: triamcinolone acetonide (TA) assistance and/or internal limiting membrane (ILM) peeling for the treatment of highly myopic macular hole retinal detachment (MHRD). Case-control study. Pars plana vitrectomy combined with 2 kinds of adjuvant surgical procedures were used on 96 highly myopic eyes with MHRD. These eyes were assigned to 4 groups randomly: Group 1, non-TA-assisted PPV and without ILM peeling; Group 2, non-TA-assisted PPV with ILM peeling; Group 3, TA-assisted PPV and without ILM peeling; Group 4, TA-assisted PPV with ILM peeling. Anatomical reattachment of the retina, macular hole closure, and best-corrected visual acuity were measured. The rates of both retinal reattachment and macular hole closure were higher in Group 2 (84.0 and 44.0%) and Group 3 (80.8 and 46.2%) than Group 1 (73.9 and 17.4%); however, there were no differences between Group 2 and Group 3 (P > 0.05). The rates of macular hole closure were extremely low in Group 1 and also in eyes with extreme long axial lengths (≥29.0 mm), "severe" chorioretinal atrophy, and posterior staphyloma. Pars plana vitrectomy with either TA assistance or ILM peeling was effective for the treatment of highly myopic MHRD. If you peel the ILM, adding TA does not affect closure rates; and if TA is used to visualize the vitreous, ILM peeling may not be necessary in MHRD. There was a lower anatomical success rate in MHRD with extreme long axial lengths, severe chorioretinal atrophy, and posterior staphyloma.
Borro, José M; Regueiro, Francisco; Pértega, Sonia; Constenla, Manuel; Pita, Salvador
2017-04-01
Video-assisted thoracoscopic surgery has become the technique of choice in the early stages of lung cancer in many centers although there is no evidence that all of the surgical approaches achieve the same long-term survival. We carried out a retrospective review of 276 VATS lobectomies performed in our department, analyzing age, sex, comorbidities, current smoker, FEV1 and FCV, surgical approach, TNM and pathological stage, histologic type, neoadjuvant or coadjuvant chemotherapy, relapse and metastasis time, with the main aim of evaluating the survival rate and disease-free time, especially with regard to the two/three versus single port approach. The one/four year global survival rate was 88.1 and 67.6% respectively. Bivariate analysis found that the variables associated with survival are comorbidity, histological type, stage, surgical approach and need for chemotherapy. When we independently analyzed the surgical approach, we found a lower survival rate in the single-port group vs. the two/three-port group (VATS). Stratifying by tumoral stage (stage I) and by tumor size (T2) survival was significantly lower for patients with single-port group in comparison to VATS approach. In the multivariate analysis, single-port group is associated with a higher risk of death (HR=1.78). In analyzing disease-free survival, differences were found in both cases in favor of two/three port VATS: p=.093 for local relapses and p=.091 for the development of metastasis. These results challenge the use of the single port technique in malignant lung pathologies, suggesting the need for clinical trials in order to identify the role this technique may have in lung cancer surgery. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.
Fertility sparing surgery in early stage epithelial ovarian cancer
Martinelli, Fabio; Lorusso, Domenica; Haeusler, Edward; Carcangiu, Marialuisa; Raspagliesi, Francesco
2014-01-01
Objective Fertility sparing surgery (FSS) is a strategy often considered in young patients with early epithelial ovarian cancer. We investigated the role and the outcomes of FSS in eEOC patients who underwent comprehensive surgery. Methods From January 2003 to January 2011, 24 patients underwent fertility sparing surgery. Eighteen were one-to-one matched and balanced for stage, histologic type and grading with a group of patients who underwent radical comprehensive staging (n=18). Demographics, surgical procedures, morbidities, pathologic findings, recurrence-rate, pregnancy-rate and correlations with disease-free survival were assessed. Results A total of 36 patients had a complete surgical staging including lymphadenectomy and were therefore analyzed. Seven patients experienced a recurrence: four (22%) in the fertility sparing surgery group and three (16%) in the control group (p=not significant). Sites of recurrence were: residual ovary (two), abdominal wall and peritoneal carcinomatosis in the fertility sparing surgery group; pelvic (two) and abdominal wall in the control group. Recurrences in the fertility sparing surgery group appeared earlier (mean, 10.3 months) than in radical comprehensive staging group (mean, 53.3 months) p<0.001. Disease-free survival were comparable between the two groups (p=0.422). No deaths were reported. All the patients in fertility sparing surgery group recovered a regular period. Thirteen out of 18 (72.2%) attempted to have a pregnancy. Five (38%) achieved a spontaneous pregnancy with a full term delivery. Conclusion Fertility sparing surgery in early epithelial ovarian cancer submitted to a comprehensive surgical staging could be considered safe with oncological results comparable to radical surgery group. PMID:25142621
High-contrast 3D image acquisition using HiLo microscopy with an electrically tunable lens
NASA Astrophysics Data System (ADS)
Philipp, Katrin; Smolarski, André; Fischer, Andreas; Koukourakis, Nektarios; Stürmer, Moritz; Wallrabe, Ulricke; Czarske, Jürgen
2016-04-01
We present a HiLo microscope with an electrically tunable lens for high-contrast three-dimensional image acquisition. HiLo microscopy combines wide field and speckled illumination images to create optically sectioned images. Additionally, the depth-of-field is not fixed, but can be adjusted between wide field and confocal-like axial resolution. We incorporate an electrically tunable lens in the HiLo microscope for axial scanning, to obtain three-dimensional data without the need of moving neither the sample nor the objective. The used adaptive lens consists of a transparent polydimethylsiloxane (PDMS) membrane into which an annular piezo bending actuator is embedded. A transparent fluid is filled between the membrane and the glass substrate. When actuated, the piezo generates a pressure in the lens which deflects the membrane and thus changes the refractive power. This technique enables a large tuning range of the refractive power between 1/f = (-24 . . . 25) 1/m. As the NA of the adaptive lens is only about 0.05, a fixed high-NA lens is included in the setup to provide high resolution. In this contribution, the scan properties and capabilities of the tunable lens in the HiLo microscope are analyzed. Eventually, exemplary measurements are presented and discussed.
Precision lens assembly with alignment turning system
NASA Astrophysics Data System (ADS)
Ho, Cheng-Fang; Huang, Chien-Yao; Lin, Yi-Hao; Kuo, Hui-Jean; Kuo, Ching-Hsiang; Hsu, Wei-Yao; Chen, Fong-Zhi
2017-10-01
The poker chip assembly with high precision lens barrels is widely applied to ultra-high performance optical system. ITRC applies the poker chip assembly technology to the high numerical aperture objective lenses and lithography projection lenses because of its high efficiency assembly process. In order to achieve high precision lens cell for poker chip assembly, an alignment turning system (ATS) is developed. The ATS includes measurement, alignment and turning modules. The measurement module is equipped with a non-contact displacement sensor (NCDS) and an autocollimator (ACM). The NCDS and ACM are used to measure centration errors of the top and the bottom surface of a lens respectively; then the amount of adjustment of displacement and tilt with respect to the rotational axis of the turning machine for the alignment module can be determined. After measurement, alignment and turning processes on the ATS, the centration error of a lens cell with 200 mm in diameter can be controlled within 10 arcsec. Furthermore, a poker chip assembly lens cell with three sub-cells is demonstrated, each sub-cells are measured and accomplished with alignment and turning processes. The lens assembly test for five times by each three technicians; the average transmission centration error of assembly lens is 12.45 arcsec. The results show that ATS can achieve high assembly efficiency for precision optical systems.
Continuous flow dielectrophoretic particle concentrator
Cummings, Eric B [Livermore, CA
2007-04-17
A continuous-flow filter/concentrator for separating and/or concentrating particles in a fluid is disclosed. The filter is a three-port device an inlet port, an filter port and a concentrate port. The filter separates particles into two streams by the ratio of their dielectrophoretic mobility to their electrokinetic, advective, or diffusive mobility if the dominant transport mechanism is electrokinesis, advection, or diffusion, respectively.Also disclosed is a device for separating and/or concentrating particles by dielectrophoretic trapping of the particles.
Park, Henry S; Gross, Cary P; Makarov, Danil V; Yu, James B
2012-08-01
To evaluate the influence of immortal time bias on observational cohort studies of postoperative radiotherapy (PORT) and the effectiveness of sequential landmark analysis to account for this bias. First, we reviewed previous studies of the Surveillance, Epidemiology, and End Results (SEER) database to determine how frequently this bias was considered. Second, we used SEER to select three tumor types (glioblastoma multiforme, Stage IA-IVM0 gastric adenocarcinoma, and Stage II-III rectal carcinoma) for which prospective trials demonstrated an improvement in survival associated with PORT. For each tumor type, we calculated conditional survivals and adjusted hazard ratios of PORT vs. postoperative observation cohorts while restricting the sample at sequential monthly landmarks. Sixty-two percent of previous SEER publications evaluating PORT failed to use a landmark analysis. As expected, delivery of PORT for all three tumor types was associated with improved survival, with the largest associated benefit favoring PORT when all patients were included regardless of survival. Preselecting a cohort with a longer minimum survival sequentially diminished the apparent benefit of PORT. Although the majority of previous SEER articles do not correct for it, immortal time bias leads to altered estimates of PORT effectiveness, which are very sensitive to landmark selection. We suggest the routine use of sequential landmark analysis to account for this bias. Copyright © 2012 Elsevier Inc. All rights reserved.
Design considerations of a real-time clinical confocal microscope
NASA Astrophysics Data System (ADS)
Masters, Barry R.
1991-06-01
A real-time clinical confocal light microscope provides the ophthalmologist with a new tool for the observation of the cornea and the ocular lens. In addition, the ciliary body, the iris, and the sclera can be observed. The real-time light microscopic images have high contrast and resolution. The transverse resolution is about one half micron and the range resolution is one micron. The following observations were made with visible light: corneal epithelial cells, wing cells, basal cells, Bowman's membrane, nerve fibers, basal lamina, fibroblast nuclei, Descemet's membrane, endothelial cells. Observation of the in situ ocular lens showed lens capsule, lens epithelium, lens fibrils, the interior of lens fibrils. The applications of the confocal microscope include: eye banking, laser refractive surgery, observation of wound healing, observation of the iris, the sciera, the ciliary body, the ocular lens, and the intraocular lens. Digital image processing can produce three-dimensional reconstructions of the cornea and the ocular lens.
Fang, Shirong; Yang, Jinhong; Song, Lei; Jiang, Yan; Liu, Yuxiu
2017-01-01
Background Central venous catheters (CVCs) have been an effective access for chemotherapy instead of peripherally intravenous catheters. There were limited studies on the choices and effects of different types of CVCs for chemotherapy. The aim of this study was to compare the complications, cost, and patients’ quality of life and satisfaction of three commonly used CVCs for chemotherapy, such as implanted venous port, peripherally inserted central catheters (PICCs), and external non-tunneled central venous catheters (NTCs). Methods A double-center prospective cohort study was carried out from March 2014 to December 2016. Catheterization situation, complications, catheter maintenance, cost, and patients’ quality of life and satisfaction were recorded, investigated, and analyzed. Forty-five ports, 60 PICCs and 40 NTCs were included. All the CVCs were followed up to catheter removal. Results There was no statistical difference in catheterization success rates between port and PICC. NTC had less success rate by one puncture compared with port. Ports had fewer complications compared with PICCs and NTCs. The complication rates of ports, PICCs and NTCs were 2.2%, 40%, and 27.5%, respectively. If the chemotherapy process was <12 months, NTCs cost least, and the cost of port was much higher than PICC and NTC. When the duration time was longer than 12 months, the cost of port had no difference with the cost of PICC. Quality of life and patients’ satisfaction of port group were significantly higher than the other two groups. Conclusion Although port catheterization costs more and needs professional medical staff and strict operational conditions, ports have fewer complications and higher quality of life and patients’ satisfaction than PICCs and NTCs. Therefore, not following consideration of the economic factor, we recommend port as a safe and an effective chemotherapy access for cancer patients, especially for whom needing long chemotherapy process. PMID:28744109
Shimada, Hiroyuki
2014-01-01
Vitrectomy is one of the ophthalmic surgeries that require a large number of instruments. Despite a growing array of single-use disposable instruments, vitrectomies for refractory diseases still involve complicated procedures and many surgical devices. As to the arrangement of materials and instruments on the surgical table, fluids that must not be introduced intraocularly, infusion fluid for washing the ocular surface, fluids for intraocular injection, and fluids for periocular injection are classified and marked to avoid using the wrong fluid. Since bacteria are present in the fluid retained in the fluid catch bag, the accumulated infusion fluid should be removed by aspiration. © 2014 S. Karger AG, Basel
Cywiński, Adam; Kałużny, Jakub; Ferda, Daniela; Piwońska-Lobermajer, Anna
2015-01-01
Retrospective evaluation of functional and anatomical treatment outcomes in patients with macular cornplications of optic disc pit. 9 patients (eyes) underwent central posterior vitrectomy in conjunction with posterior vitreous detachment, retinal laser therapy to the optic disc pit area and endotamponade with expansile gas. It was followed by the patient's forced positioning (recommended for a few days especially at night), which ended the treatment protocol. Improved anatomical relationships, accompanied by functional improvement were achieved in each reported case. The resolution of macular lesions was slow, lasting even for several months. Too long delay in performing the surgery (over 5 months since the onset of visual impairment) was associated with the development of retinal complications, mainly macular hole formation, most likely caused by the long-term ischemia. The central posterior vitrectomy combined with posterior vitreous detachment, laser therapy, andd expansile gas tamponade offers good outcomes in patients with retinal complications of optic disc pit. Surgery performed shortly after the onset of visual dysfunction gives the best functional outcomes. Restoration of normal anatomical relationships is a long-term process. In some cases, though, these abnormalities may not resolve completely.
Intravitreal Bevacizumab (Avastin) for Diabetic Retinopathy: The 2010 GLADAOF Lecture
Arevalo, J. Fernando; Sanchez, Juan G.; Lasave, Andres F.; Wu, Lihteh; Maia, Mauricio; Bonafonte, Sergio; Brito, Miguel; Alezzandrini, Arturo A.; Restrepo, Natalia; Berrocal, Maria H.; Saravia, Mario; Farah, Michel Eid; Fromow-Guerra, Jans; Morales-Canton, Virgilio
2011-01-01
This paper demonstrates multiple benefits of intravitreal bevacizumab (IVB) on diabetic retinopathy (DR) including diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) at 24 months of followup. This is a retrospective multicenter interventional comparative case series of intravitreal injections of 1.25 or 2.5 mg of bevacizumab for DME, PDR without tractional retinal detachment (TRD), and patients who experienced the development or progression of TRD after an intravitreal injection of 1.25 or 2.5 mg of bevacizumab before vitrectomy for the management of PDR. The results indicate that IVB injections may have a beneficial effect on macular thickness and visual acuity (VA) in diffuse DME. Therefore, in the future this new therapy could complement focal/grid laser photocoagulation in DME. In PDR, this new option could be an adjuvant agent to panretina photocoagulation so that more selective therapy may be applied. Finally, TRD in PDR may occur or progress after IVB used as an adjuvant to vitrectomy. Surgery should be performed 4 days after IVB. Most patients had poorly controlled diabetes mellitus associated with elevated HbA1c, insulin administration, PDR refractory to panretinal photocoagulation, and longer time between IVB and vitrectomy. PMID:21584260
INCOMPLETE REPAIR OF RETINAL STRUCTURE AFTER VITRECTOMY WITH INTERNAL LIMITING MEMBRANE PEELING.
Hisatomi, Toshio; Tachibana, Takashi; Notomi, Shoji; Nakatake, Shunji; Fujiwara, Kohta; Murakami, Yusuke; Ikeda, Yasuhiro; Yoshida, Shigeo; Enaida, Hiroshi; Murata, Toshinori; Sakamoto, Taiji; Sonoda, Koh-Hei; Ishibashi, Tatsuro
2017-08-01
To examine retinal changes after vitrectomy with internal limiting membrane (ILM) peeling, we used a cynomolgus monkey model and focused on surgical damages of ILM peeling for long observational period of 3 years. Vitrectomy was performed followed by ILM peeling similar to clinical settings in humans. Ultrastructural changes of the retina were investigated by light, transmission, and scanning electron microscopy at 3 months and 3 years after ILM peeling. Ultrastructural study showed that the ILM peeled area was still clearly recognized after 3 years. The Müller cell processes covered most of the retina; however, the nerve fiber layer was partly uncovered and exposed to the vitreous space. The arcuate linear nerve fiber bundles were observed as comparable with dissociated optic nerve fiber layer appearance. Small round retinal surface defects were also observed around macula, resembling the dimple sign. Forceps-related retinal thinning was also found on the edge of ILM peeling, where we started peeling with fine forceps. The ultrastructural studies showed that most of ILM peeling area was covered with glial cells during wound healing processes. Retinal changes were found comparable with dissociated optic nerve fiber layer appearance or dimple sign, which were clinically observed with optical coherence tomography.
Predictive factors of open globe injury in patients requiring vitrectomy.
Pimolrat, Weeraya; Choovuthayakorn, Janejit; Watanachai, Nawat; Patikulsila, Direk; Kunavisarut, Paradee; Chaikitmongkol, Voraporn; Ittipunkul, Nimitr
2014-01-01
To determine the outcomes and predictive factors of patients with open globe injury requiring pars plana vitrectomy (PPV). The medical records of 114 patients age 10 years or older who had undergone PPV due to ocular trauma, with at least 6 months follow up, were retrospectively reviewed. The mean age of the patients was 42 (SD14) years, with males accounting for 89% of the cases. Penetrating eye injury was the most common injury mechanism (43%) with most injuries occurring secondary to work related incidents (54%). After surgical interventions, 78% of the patients had visual improvement of one or more Snellen lines, while no light perception occurred in 10%. Anatomical attachment was achieved in 87% of eyes at the final follow up. Logistic regression analysis showed that the presence of a relative afferent pupillary defect (RAPD) was a significant predictive factor of visual outcome, while initial retinal detachment was a significant predictor of anatomical outcome. Pupillary reaction is an important presenting ocular sign in estimating the post-vitrectomy poor visual outcome for open globe injury. Vision was restored and improved in more than half of the patients in this study; however, long-term sequelae should be monitored. Copyright © 2013 Elsevier Ltd. All rights reserved.
Gadkari, Salil; Kamdar, Rushita; Kulkarni, Sucheta; Deshpande, Madan; Taras, Sudhir
2015-05-01
To demonstrate improvement in the vision of babies after successful vitrectomy for stage 4b retinopathy of prematurity (ROP) over an extended period of time. This was an observational prospective case series. Eight babies who had undergone successful vitrectomy in either their only seeing eye (or both eyes) with stage 4b ROP were followed up post-operatively for a period of 80 weeks or more. Vision with Teller acuity chart, refraction, binocular indirect ophthalmoscopy, and documentation with RetCam was done at each visit. Vision of the (only/better) seeing operated eye with corrective glasses was graded for the purpose of statistical evaluation. Paired t test was performed to compare the vision prior to 30 weeks and at or after 80 weeks. Statistically significant improvement in vision was noted at or after 80 weeks as compared to the vision recorded before 30 weeks (p = 0.0062). Unlike in adult intraocular surgeries where stable visual acuity is reached well before 30 weeks, continuing improvement at 80 weeks and beyond is noted. Gradual restoration of the retinal architecture and plasticity of the infant's developing brain are thought to be responsible.
Development of three-dimensional tracking system using astigmatic lens method for microscopes
NASA Astrophysics Data System (ADS)
Kibata, Hiroki; Ishii, Katsuhiro
2017-07-01
We have developed a three-dimensional tracking system for microscopes. Using the astigmatic lens method and a CMOS image sensor, we realize a rapid detection of a target position in a wide range. We demonstrate a target tracking using the developed system.
NASA Technical Reports Server (NTRS)
Garecht, D. M.
1988-01-01
The Three-in-One Gage is a three way gage designed to measure pressure, temperature, and displacement at the same port continuously. The Two-in-One Gage is a two way gage designed to measure pressure and temperature in the same port continuously. The Two-in-One is an adaptation of the Three-in-One to incorporate dual seals, however, without the proximity sensor. The Three-in-One is assembled using two Type K thermocouples, 1 Kulite Pressure Transducer, and one Kaman Proximity Displacement Sensor. Tests of performance were completed.
The cellular and molecular mechanisms of vertebrate lens development
Cvekl, Aleš; Ashery-Padan, Ruth
2014-01-01
The ocular lens is a model system for understanding important aspects of embryonic development, such as cell specification and the spatiotemporally controlled formation of a three-dimensional structure. The lens, which is characterized by transparency, refraction and elasticity, is composed of a bulk mass of fiber cells attached to a sheet of lens epithelium. Although lens induction has been studied for over 100 years, recent findings have revealed a myriad of extracellular signaling pathways and gene regulatory networks, integrated and executed by the transcription factor Pax6, that are required for lens formation in vertebrates. This Review summarizes recent progress in the field, emphasizing the interplay between the diverse regulatory mechanisms employed to form lens progenitor and precursor cells and highlighting novel opportunities to fill gaps in our understanding of lens tissue morphogenesis. PMID:25406393
Annular folded electrowetting liquid lens.
Li, Lei; Liu, Chao; Ren, Hongwen; Deng, Huan; Wang, Qiong-Hua
2015-05-01
We report an annular folded electrowetting liquid lens. The front surface of the lens is coated with a circular reflection film, while the back surface of the lens is coated with a ring-shaped reflection film. This approach allows the lens to get optical power from the liquid-liquid interface three times so that the optical power is tripled. An analysis of the properties of the annular folded electrowetting liquid lens is presented along with the design, fabrication, and testing of a prototype. Our results show that the optical power of the proposed liquid lens can be enhanced from ∼20.1 to ∼50.2 m(-1) in comparison with that of the conventional liquid lens (aperture ∼3.9 mm). It can reduce the operating voltage by ∼10 V to reach the same diopter as a conventional liquid lens. Our liquid lens has the advantages of compact structure, light weight, and improved optical resolution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ramezani, Hamidreza; Dubois, Marc; Wang, Yuan
Here, we propose a mechanism for directional excitation without breaking reciprocity. This is achieved by embedding an impedance matched parity-time symmetric potential in a three-port system. The amplitude distribution within the gain and loss regions is strongly influenced by the direction of the incoming field. Consequently, the excitation of the third port is contingent on the direction of incidence while transmission in the main channel is immune. This design improves the four-port directional coupler scheme, as there is no need to implement an anechoic termination to one of the ports.
Colyer, Marcus H; Weber, Eric D; Weichel, Eric D; Dick, John S B; Bower, Kraig S; Ward, Thomas P; Haller, Julia A
2007-08-01
To report the long-term follow-up results of intraocular foreign body (IOFB) removal at Walter Reed Army Medical Center during Operation Iraqi Freedom and Operation Enduring Freedom from February 2003 through November 2005 and to determine the prognostic factors for visual outcome in this patient population. Retrospective, noncomparative, interventional case series. Seventy-nine eyes of 70 United States military soldiers deployed in support of operations Iraqi Freedom and Enduring Freedom sustained IOFB injuries and subsequently were treated at the Walter Reed Army Medical Center with a minimum of 6 months of follow-up. The principal procedure performed was 20-gauge 3-port vitrectomy with IOFB removal through limbal or pars plana incision. Final visual acuity, rate of proliferative vitreoretinopathy, rate of endophthalmitis. Average patient age was 27 years, with an average of 331 days of postoperative follow-up. Average IOFB size was 3.7 mm (range, 0.1-20 mm). Median time to IOFB removal was 21 days (mean, 38 days; range, 2-661 days). Mean preoperative visual acuity was 20/400 (1.36 logarithm of mean angle of resolution [logMAR] units) and mean final visual acuity was 20/120 (0.75 logMAR). Of the patients, 53.4% achieved visual acuity of 20/40 or better, whereas 77.5% achieved visual acuity of better than 20/200. There were no cases of endophthalmitis (0/79 eyes; 95% confidence interval, 0%-3.1%), siderosis bulbi, or sympathetic ophthalmia. Among the eyes, 10.3% evolved to no light perception or had been enucleated by the 6-month follow-up visit. Poor visual outcome correlated with extensive intraocular injury (P<0.032). Seventeen of 79 eyes (21%) experienced proliferative vitreoretinopathy. Proliferative vitreoretinopathy correlated with poor initial vision (hand movements or worse; P = 0.035) and extensive intraocular injury (P<0.001). Timing of vitrectomy did not correlate with visual outcome. The most common systemic antibiotic administered was levofloxacin, whereas the most common topical antibiotic administered was moxifloxacin. Poor visual outcome and postoperative complication rates are related to extensive intraocular injury. Delayed IOFB removal with a combination of systemic and topical antibiotic coverage can result in good visual outcome without an apparent increased risk of endophthalmitis or other deleterious side effects.
One, Two, or Three Ports in Laparoscopic Cholecystectomy?
Justo-Janeiro, Jaime Manuel; Vincent, Gustavo Theurel; Vázquez de Lara, Fernando; de la Rosa Paredes, René; Orozco, Eduardo Prado; Vázquez de Lara, Luis G.
2014-01-01
Single-port laparoscopic cholecystectomy (LC) has been compared with 3- or 4-port LC. To our knowledge, there are no studies comparing the 3-, 2-, and 1-port techniques. Patients were randomized into 3 groups: LC 1-port using SILS, LC 2-port using a laparoscope with a working channel, and LC 3-port using the standard ports. Pain was evaluated at recovery, 4 hours, 24 hours, day 5, and day 8, using an analog visual scale. Homogenous groups in their demographic characteristics; all confirmed gallbladder lithiasis. At recovery, there was less pain in group 1 (P = 0.002); at 4 hours pain was similar in all groups (P = 0.899); at 24 hours there was less pain in groups 2 and 3 (P = 0.031); and at days 5 and 8 there was marginal (P = 0.053) and significant (P = 0.003) relevance. In terms of pain perception, LC performed through 1 port does not offer advantages when compared with 2 or 3 ports. More clinical trials are needed to confirm these data. PMID:25437581
Kim, Min; Lee, Dong H; Koh, Hyoung J; Lee, Sung C; Kim, Sung S
2015-07-01
To report short-term surgical outcomes of single-stage simultaneous rescue and sutureless intrascleral fixation of dislocated intraocular lens (IOLs). Sixteen eyes of 16 patients who underwent simultaneous rescue and intrascleral fixation of dislocated 3-piece IOLs were retrospectively evaluated. Partial thickness limbal-based scleral flaps (2.0 × 2.0 mm) were created, and a 22-gauge round needle was used to create a sclerotomy at 1.5 mm from the limbus under the previously created scleral flap, and a 23-gauge trans pars plana vitrectomy was performed. Bimanual maneuvers using two 23-gauge end-grasping forceps under chandelier illumination and a wide-angle viewing system enabled 1 step rescue of IOLs from the posterior vitreous cavity with 1 hand and simultaneous haptic externalization through sclerotomy with the other hand. An externalized haptic was placed into the 3-mm intrascleral tunnel created using a bent 26-gauge needle. Fibrin glue was used to fixate haptics and close the scleral flaps. Intraocular lenses were successfully rescued and sclera-fixated through intrascleral tunnels in all 16 eyes (mean age, 56.56 ± 19.89 years). The mean preoperative logarithm of the minimum angle of resolution best-corrected visual acuity was 0.92 ± 0.68, and this significantly improved at 6 months to 0.289 ± 0.36 (P = 0.003). During the follow-up period (10.1 ± 3.21 months), no significant change of endothelial cell count or central foveal thickness was noted postoperatively (P = 0.203 and P = 0.979, respectively). There were no significant postoperative complications such as IOL dislocation, IOL decentration, retinal detachment, endophthalmitis, or postoperative hypotony. Simultaneous rescue and sutureless intrascleral haptic fixation of dislocated 3-piece IOLs using bimanual maneuvers is an effective, safe, and minimally invasive surgical method to rescue and fixate the dislocated IOL without further explant.
Lens-Specific Gene Recruitment of ζ-Crystallin through Pax6, Nrl-Maf, and Brain Suppressor Sites
Sharon-Friling, Ronit; Richardson, Jill; Sperbeck, Sally; Lee, Douglas; Rauchman, Michael; Maas, Richard; Swaroop, Anand; Wistow, Graeme
1998-01-01
ζ-Crystallin is a taxon-specific crystallin, an enzyme which has undergone direct gene recruitment as a structural component of the guinea pig lens through a Pax6-dependent mechanism. Tissue specificity arises through a combination of effects involving three sites in the lens promoter. The Pax6 site (ZPE) itself shows specificity for an isoform of Pax6 preferentially expressed in lens cells. High-level expression of the promoter requires a second site, identical to an αCE2 site or half Maf response element (MARE), adjacent to the Pax6 site. A promoter fragment containing Pax6 and MARE sites gives lens-preferred induction of a heterologous promoter. Complexes binding the MARE in lens nuclear extracts are antigenically related to Nrl, and cotransfection with Nrl elevates ζ-crystallin promoter activity in lens cells. A truncated ζ promoter containing Nrl-MARE and Pax6 sites has a high level of expression in lens cells in transgenic mice but is also active in the brain. Suppression of the promoter in the brain requires sequences between −498 and −385, and a site in this region forms specific complexes in brain extract. A three-level model for lens-specific Pax6-dependent expression and gene recruitment is suggested: (i) binding of a specific isoform of Pax6; (ii) augmentation of expression through binding of Nrl or a related factor; and (iii) suppression of promoter activity in the central nervous system by an upstream negative element in the brain but not in the lens. PMID:9528779
Suspension and optical properties of the crystalline lens in the eyes of basal vertebrates.
Kröger, Ronald H H; Gustafsson, Ola S E; Tuminaite, Inga
2014-06-01
We have investigated the apparatus suspending the crystalline lens in the eyes of basal vertebrates. Data are presented for Holocephali (Chondrichthyes) and the actinopterygians Polypteriformes, Polyodontidae (Acipenseriformes), Lepisosteiformes, Amiiformes, and one teleost species, the banded archerfish (Toxotes jaculatrix). We also studied the optical properties of the lens in Polypteriformes, Lepisosteiformes, and the archerfish. Together with previously published results, our findings show that there are three basic types of lens suspension in vertebrates. These are i) a rotationally symmetric suspension (Petromyzontida, lampreys; Ceratodontiformes, lungfishes; Tetrapoda), ii) a suspension with a dorso-ventral axis of symmetry and a ventral papilla (all Chondrichthyes and Acipenseriformes), and iii) an asymmetric suspension with a ventral muscle and a varying number of ligaments (all Actinopterygii except for Acipenseriformes). Large eyes with presumably high spatial resolution have evolved in all groups. Multifocal lenses creating well-focused color images are also present in all groups studied. Stable and exact positioning of the lens, in many cases in combination with accommodative changes in lens position or shape, is achieved by all three types of lens suspension. It is somewhat surprising that lens suspensions are strikingly similar in Chondrichthyes and Acipenseriformes (Actinopterygii), while the suspension apparatus in Polypteriformes, usually being regarded as an actinopterygian group more basal than Acipenseriformes, are considerably more teleostean-like. This study completes a series of investigations on lens suspensions in nontetrapod vertebrates, covering all major groups except for the rare and highly derived coelacanths. Copyright © 2013 Wiley Periodicals, Inc.
Preventing Mitochondrial Diseases: Embryo-Sparing Donor-Independent Options.
Adashi, Eli Y; Cohen, I Glenn
2018-05-01
Mutant mitochondrial DNA gives rise to a broad range of incurable inborn maladies. Prevention may now be possible by replacing the mutation-carrying mitochondria of zygotes or oocytes at risk with donated unaffected counterparts. However, mitochondrial replacement therapy is being held back by theological, ethical, and safety concerns over the loss of human zygotes and the involvement of a donor. These concerns make it plain that the identification, validation, and regulatory adjudication of novel embryo-sparing donor-independent technologies remains a pressing imperative. This Opinion highlights three emerging embryo-sparing donor-independent options that stand to markedly allay theological, ethical, and safety concerns raised by mitochondrial replacement therapy. Copyright © 2018 Elsevier Ltd. All rights reserved.
Numerical analyses of planer plasmonic focusing lens
NASA Astrophysics Data System (ADS)
Chou, Yen-Yu; Lee, Yeeu-Chang
2018-03-01
The use of polystyrene (PS) sphere lithography has been widely applied in the fabrication of micron and nano structures, due to their low cost and ease of fabrication in large scale applications. This study evaluated the feasibility of plasmonic lens base on metal thin films with nanohole structures fabricated by using PS sphere lithography through three-dimensional (3D) finite difference time domain (FDTD) method. We calculated the intensity profile of lens with various wavelength of incident light, lens size, cutting positions, diameters of nanohole, and periods of nanohole to investigate the geometric parameters influence on the focusing properties of the plasmonic lens.
The Influence of Different OK Lens Designs on Peripheral Refraction.
Kang, Pauline; Swarbrick, Helen
2016-09-01
To compare peripheral refraction changes along the horizontal and vertical meridians induced by three different orthokeratology (OK) lens designs: BE, Paragon CRT, and Contex lenses. Nineteen subjects (6M, 13F, mean age 28 ± 7 years) were initially fitted with BE OK lenses in both eyes which were worn overnight for 14 days. Central and peripheral refraction and corneal topography were measured at baseline and after 14 nights of lens wear. After a minimum 2-week washout period, one randomly selected eye was re-fitted with a Paragon CRT lens and the other eye with a Contex OK lens. Measurements were repeated before and after 14 nights of lens wear. The three different OK lenses caused significant changes in peripheral refraction along both the horizontal and vertical visual fields (VFs). BE and Paragon CRT lenses induced a significant hyperopic shift within the central ±20° along the horizontal VF and at all positions along the vertical meridian except at 30° in the superior VF. There were no significant differences in peripheral refraction changes induced between BE and Paragon CRT lenses. When comparing BE and Contex OK lens designs, BE caused greater hyperopic shifts at 10° and 30° in the temporal VF and at center, 10°, and 20° in the superior VF along the vertical meridian. Furthermore, BE lenses caused greater reduction in Flat and Steep K values compared to Contex OK. OK lenses induced significant changes in peripheral refraction along the horizontal and vertical meridians. Despite the clinically significant difference in central corneal flattening induced by BE and Contex OK lenses, relative peripheral refraction changes differed minimally between the three OK lens designs. If the peripheral retina influences refractive error development, these results suggest that myopia control effects are likely to be similar between different OK lens designs.
Membrane-less variable focus liquid lens with manual actuation
NASA Astrophysics Data System (ADS)
Patra, Roshan; Agarwal, Shivam; Kondaraju, Sasidhar; Bahga, Supreet Singh
2017-04-01
We present a tunable, membrane-less, mechanical-wetting liquid lens that can be actuated manually using a linear actuator such as screw or piston. The operation of the liquid lens is based on deforming the interface separating two immiscible liquids with different refractive indices, while pinning the three-phase contact line at the sharp edge of lens aperture. Our lens design improves upon the existing designs of mechanical-wetting lenses by eliminating the use of complex actuation mechanisms, without compromising on the optical performance. We demonstrate the operation of the liquid lens by tuning its power back and forth from negative to positive by simple rotation of a screw. We also present an analytical description of the focal length of the lens and validate it with detailed experimental measurements. Our experiments show that the focal length of the liquid lens can be tuned repeatably without any adverse effects of hysteresis and gravity.
Effect of driving voltage polarity on dynamic response characteristics of electrowetting liquid lens
NASA Astrophysics Data System (ADS)
Na, Xie; Ning, Zhang; Rong-Qing, Xu
2018-05-01
A test device is developed for studying the dynamic process of an electrowetting liquid lens. By analyzing the light signals through the liquid lens, the dynamical properties of the lens are investigated. In our experiment, three types of pulse, i.e., sine, bipolar pulse, and single pulse signals, are employed to drive the liquid lens, and the dynamic characteristics of the lens are subsequently analyzed. The results show that the positive and negative polarities of the driving voltage can cause a significant difference in the response of the liquid lens; meanwhile, the lens’s response to the negative polarity of the driving voltage is clearer. We use the theory of charge restraint to explain this phenomenon, and it is concluded that the negative ions are more easily restrained by a dielectric layer. This work gives direct guidance for practical applications based on an electrowetting liquid lens.
77 FR 30245 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-22
...-AA00 Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone AGENCY: Coast Guard... by adding three permanent safety zones within the Captain of the Port Detroit Zone. This action is necessary to provide for the safety of life and property on navigable waters during each event. This action...
DNA in a bottle-Rapid metabarcoding survey for early alerts of invasive species in ports.
Borrell, Yaisel J; Miralles, Laura; Do Huu, Hoang; Mohammed-Geba, Khaled; Garcia-Vazquez, Eva
2017-01-01
Biota monitoring in ports is increasingly needed for biosecurity reasons and safeguarding marine biodiversity from biological invasion. Present and future international biosecurity directives can be accomplished only if the biota acquired by maritime traffic in ports is controlled. Methodologies for biota inventory are diverse and now rely principally on extensive and labor-intensive sampling along with taxonomic identification by experts. In this study, we employed an extremely simplified environmental DNA (eDNA) sampling methodology from only three 1-L bottles of water per port, followed by metabarcoding (high-throughput sequencing and DNA-based species identification) using 18S rDNA and Cytochrome oxidase I as genetic barcodes. Eight Bay of Biscay ports with available inventory of fouling invertebrates were employed as a case study. Despite minimal sampling efforts, three invasive invertebrates were detected: the barnacle Austrominius modestus, the tubeworm Ficopomatus enigmaticus and the polychaete Polydora triglanda. The same species have been previously found from visual and DNA barcoding (genetic identification of individuals) surveys in the same ports. The current costs of visual surveys, conventional DNA barcoding and this simplified metabarcoding protocol were compared. The results encourage the use of metabarcoding for early biosecurity alerts.
DNA in a bottle—Rapid metabarcoding survey for early alerts of invasive species in ports
Miralles, Laura; Do Huu, Hoang; Mohammed-Geba, Khaled; Garcia-Vazquez, Eva
2017-01-01
Biota monitoring in ports is increasingly needed for biosecurity reasons and safeguarding marine biodiversity from biological invasion. Present and future international biosecurity directives can be accomplished only if the biota acquired by maritime traffic in ports is controlled. Methodologies for biota inventory are diverse and now rely principally on extensive and labor-intensive sampling along with taxonomic identification by experts. In this study, we employed an extremely simplified environmental DNA (eDNA) sampling methodology from only three 1-L bottles of water per port, followed by metabarcoding (high-throughput sequencing and DNA-based species identification) using 18S rDNA and Cytochrome oxidase I as genetic barcodes. Eight Bay of Biscay ports with available inventory of fouling invertebrates were employed as a case study. Despite minimal sampling efforts, three invasive invertebrates were detected: the barnacle Austrominius modestus, the tubeworm Ficopomatus enigmaticus and the polychaete Polydora triglanda. The same species have been previously found from visual and DNA barcoding (genetic identification of individuals) surveys in the same ports. The current costs of visual surveys, conventional DNA barcoding and this simplified metabarcoding protocol were compared. The results encourage the use of metabarcoding for early biosecurity alerts. PMID:28873426
2011-07-11
CAPE CANAVERAL, Fla. – Liberty Star, one of NASA’s solid rocket booster retrieval ships, tows a spent booster from space shuttle Atlantis’ final launch, to Port Canaveral in Florida. The shuttle’s two solid rocket booster casings and associated flight hardware are recovered in the Atlantic Ocean after every launch by Freedom Star and Liberty Star. The boosters impact the Atlantic about seven minutes after liftoff, and the retrieval ships are stationed about 10 miles from the impact area at the time of splashdown. After the spent segments are processed, they will be transported to Utah, where they will be deserviced and stored, if needed. Atlantis began its final flight, STS-135, at 11:29 a.m. EDT on July 8 to deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts to the International Space Station. Photo credit: NASA/Kim Shiflett
Changes in the crystalline lens resulting from insertion of a phakic IOL (ICL) into the porcine eye.
Fujisawa, Kunitoshi; Shimizu, Kimiya; Uga, Shigekazu; Suzuki, Masanobu; Nagano, Koichi; Murakami, Yuuki; Goseki, Hiroko
2007-01-01
Insertion of a phakic IOL offers these advantages: the corneal optical zone is not dissected or resected; preservation of the crystalline lens results in preservation of the accommodation force; and since the phakic IOL is removable, any error or change in refraction can be countered by exchanging it. However, the cause of secondary cataracts has never been clarified or discussed to date. The following ICL lenses were inserted under general anaesthesia into 20 eyes of ten 3-month-old miniature pigs: a minus lens without holes into five eyes, a plus lens in two eyes, a minus lens with four holes around the lens haptics in three eyes, and a minus lens with a central hole in the optic in three eyes; and seven eyes were used as controls. The anterior segments were then photographed 1 week, 1 month and 3 months after surgery. At 3 months after surgery, Evans blue (EB) was infused into the vitreous under general anaesthesia, and after 30 min, the eyeball was enucleated, fixed and examined. In the case of the ICL without holes, the anterior subcapsular opacities were observed in all the eyes, and the anterior surfaces of the crystalline lenses were not stained with EB. Use of the ICL with four holes around the lens haptics resulted in light staining of the anterior surface of the crystalline lens, but the anterior subcapsular opacities observed were mild. As for the ICL with a hole in the centre of the optic, the anterior surface of the crystalline lens was stained and no anterior subcapsular opacities were observed. The results suggested that the insertion of an ICL brings about a change in the dynamics of the intraocular aqueous humour, reducing its circulation to the anterior surface of the crystalline lens. This is considered to cause a metabolic disturbance of the crystalline lens, resulting in anterior subcapsular opacification.
A simple and low-cost structured illumination microscopy using a pico-projector
NASA Astrophysics Data System (ADS)
Özgürün, Baturay
2018-02-01
Here, development of a low-cost structured illumination microscopy (SIM) based on a pico-projector is presented. The pico-projector consists of independent red, green and blue LEDs that remove need for an external illumination source. Moreover, display element of the pico-projector serves as a pattern generating spatial light modulator. A simple lens group is employed to couple light from the projector to an epi-illumination port of a commercial microscope system. 2D sub SIM images are acquired and synthesized to surpass the diffraction limit using 40x (0.75 NA) objective. Resolution of the reconstructed SIM images is verified with a dye-and-object object and a fixed cell sample.
Pressure-flow reducer for aerosol focusing devices
Gard, Eric; Riot, Vincent; Coffee, Keith; Woods, Bruce; Tobias, Herbert; Birch, Jim; Weisgraber, Todd
2008-04-22
A pressure-flow reducer, and an aerosol focusing system incorporating such a pressure-flow reducer, for performing high-flow, atmosphere-pressure sampling while delivering a tightly focused particle beam in vacuum via an aerodynamic focusing lens stack. The pressure-flow reducer has an inlet nozzle for adjusting the sampling flow rate, a pressure-flow reduction region with a skimmer and pumping ports for reducing the pressure and flow to enable interfacing with low pressure, low flow aerosol focusing devices, and a relaxation chamber for slowing or stopping aerosol particles. In this manner, the pressure-flow reducer decouples pressure from flow, and enables aerosol sampling at atmospheric pressure and at rates greater than 1 liter per minute.
RImmPort: an R/Bioconductor package that enables ready-for-analysis immunology research data.
Shankar, Ravi D; Bhattacharya, Sanchita; Jujjavarapu, Chethan; Andorf, Sandra; Wiser, Jeffery A; Butte, Atul J
2017-04-01
: Open access to raw clinical and molecular data related to immunological studies has created a tremendous opportunity for data-driven science. We have developed RImmPort that prepares NIAID-funded research study datasets in ImmPort (immport.org) for analysis in R. RImmPort comprises of three main components: (i) a specification of R classes that encapsulate study data, (ii) foundational methods to load data of a specific study and (iii) generic methods to slice and dice data across different dimensions in one or more studies. Furthermore, RImmPort supports open formalisms, such as CDISC standards on the open source bioinformatics platform Bioconductor, to ensure that ImmPort curated study datasets are seamlessly accessible and ready for analysis, thus enabling innovative bioinformatics research in immunology. RImmPort is available as part of Bioconductor (bioconductor.org/packages/RImmPort). rshankar@stanford.edu. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com
Hull, C C; Crofts, N C
1996-03-01
The Beer-Lambert law has been used to determine the total attenuation coefficient, mu t, of three hard and three soft contact lens materials. The three hard contact lens materials were PMMA, Polycon II and Boston IV whereas the 3 soft materials were chosen with differing water contents of 38, 55 and 70%, respectively. The total attenuation coefficients of all six materials were obtained from measurements of the axial transmission at 632.8 nm of a series of plano powered lenses varying in axial thickness from 0.5 to 3.5 mm. The value of the total attenuation coefficient depends on both scattering and absorption and hence PMMA and Boston IV, which both incorporated a handling tint, showed significantly higher values (P < 0.0001) of mu t (0.562 +/- 0.010 mm-1 and 0.820 +/- 0.008 mm-1, respectively) than Polycon II (mu t = 0.025 +/- 0.005 mm-1). A comparison between Polycon II and the three hydrated soft contact lens materials showed a significant increase (P < 0.02) in the total attenuation coefficients for the 38% and 55% water content materials, and a weakly significant increase for the 70% water content soft lens material (P < 0.1). On the assumption that the absorption coefficients of these four materials are approximately constant, then this change would be due to an increase in the scattering coefficient of the material and could contribute to an increase in intraocular scatter. No significant difference (P > 0.5) was found between any of the hydrated soft contact lens materials tested.
Power Matters: Foucault's "Pouvoir/Savoir" as a Conceptual Lens in Information Research and Practice
ERIC Educational Resources Information Center
Olsson, Michael; Heizmann, Helena
2015-01-01
Introduction: This paper advocates Foucault's notion of pouvoir/savoir (power/knowledge) as a conceptual lens that information researchers might fruitfully use to develop a richer understanding of the relationship between knowledge and power. Methods: Three of the authors' earlier studies are employed to illustrate the use of this conceptual lens.…
A Modeling Tool for Household Biogas Burner Flame Port Design
NASA Astrophysics Data System (ADS)
Decker, Thomas J.
Anaerobic digestion is a well-known and potentially beneficial process for rural communities in emerging markets, providing the opportunity to generate usable gaseous fuel from agricultural waste. With recent developments in low-cost digestion technology, communities across the world are gaining affordable access to the benefits of anaerobic digestion derived biogas. For example, biogas can displace conventional cooking fuels such as biomass (wood, charcoal, dung) and Liquefied Petroleum Gas (LPG), effectively reducing harmful emissions and fuel cost respectively. To support the ongoing scaling effort of biogas in rural communities, this study has developed and tested a design tool aimed at optimizing flame port geometry for household biogas-fired burners. The tool consists of a multi-component simulation that incorporates three-dimensional CAD designs with simulated chemical kinetics and computational fluid dynamics. An array of circular and rectangular port designs was developed for a widely available biogas stove (called the Lotus) as part of this study. These port designs were created through guidance from previous studies found in the literature. The three highest performing designs identified by the tool were manufactured and tested experimentally to validate tool output and to compare against the original port geometry. The experimental results aligned with the tool's prediction for the three chosen designs. Each design demonstrated improved thermal efficiency relative to the original, with one configuration of circular ports exhibiting superior performance. The results of the study indicated that designing for a targeted range of port hydraulic diameter, velocity and mixture density in the tool is a relevant way to improve the thermal efficiency of a biogas burner. Conversely, the emissions predictions made by the tool were found to be unreliable and incongruent with laboratory experiments.
Contact lens management of irregular corneas after traumatic aphakia: A pediatric case series.
Aung, Yin-Yin; McLeod, Andrew
2015-10-01
Pediatric patients account for 35% of all cases that present after ocular trauma and 20.9% of those result in a ruptured globe. When repairing the globe, the removal of the natural lens results in a significant change in refractive error and loss of accommodation. In addition, the eye can have scarring, irregular astigmatism, and changes to the ocular surface. Treatment and vision rehabilitation should be aggressive and done quickly to prevent amblyopia. Advanced lens designs are often needed to treat both the irregular ocular surface and the aphakia. Treatment options are often confounded with the usual issues of contact lens compliance, intolerance, and complications. This case series follows three aphakic pediatric patients through the contact lens fitting process after sustaining a ruptured globe that left them aphakic with residual irregular astigmatism and corneal scarring. Patient 1 is a 3-year-old Hispanic male fit with a bitoric gas permeable contact lens with irregular astigmatism and an elevated central corneal scarring. Patient 2 is a 12-year-old Caucasian male with minimal residual astigmatism fit in a multifocal soft contact lens. Patient 3 is an 8-year-old African American male fit with a hybrid contact lens that was needed to vault the irregular astigmatism and central corneal scarring. Treating patients with irregular corneas or aphakia can be challenging in their own right, but in combination are some of the most advanced specialty contact lens fittings. This case series followed three pediatric patients through the fitting process and demonstrated the options and challenges when fitting this unique patient population. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
Directional excitation without breaking reciprocity
Ramezani, Hamidreza; Dubois, Marc; Wang, Yuan; ...
2016-09-02
Here, we propose a mechanism for directional excitation without breaking reciprocity. This is achieved by embedding an impedance matched parity-time symmetric potential in a three-port system. The amplitude distribution within the gain and loss regions is strongly influenced by the direction of the incoming field. Consequently, the excitation of the third port is contingent on the direction of incidence while transmission in the main channel is immune. This design improves the four-port directional coupler scheme, as there is no need to implement an anechoic termination to one of the ports.
Investigation of a Low-Drag Gun Port in the NACA Two-Dimensional Low-Turbulence Tunnel
NASA Technical Reports Server (NTRS)
Horton, Elmer A.; Woolard, Henry W.
1942-01-01
Tests were made in the NACA two-dimensional low-turbulence tunnel of three gun ports with a height of approximately 4 percent of the chord faired into an NACA 66,2-213 low-drag-airfoil section by bulging the section at the gun port. Gun ports faired in this manner had practically no effect on the maximum lift and the critical compressibility speed of the section and showed only small increase in the drag in the range of lift coefficients for high-speed and cruising-flight conditions.
Liu, Hanhan; Zuo, Shanru; Ding, Chun; Dai, Xunzhang; Zhu, Xiaohua
2015-01-01
We conducted a meta-analysis of published retrospective studies and compared the effectiveness of pars plana vitrectomy with and without internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (IERM). The results revealed that patients in the IERM+ILM peeling group had better BCVA after surgery within 12 months than those in IERM peeling group. But patients in the IERM peeling group showed better BCVA in the 18th month. More retrospective studies or randomized controlled trials are required to investigate and compare the long-term effect of IERM removal with and without ILM peeling. PMID:26693348
Vitrectomy and fluid/silicone-oil exchange for giant retinal tears: results at six months.
Leaver, P. K.; Cooling, R. J.; Feretis, E. B.; Lean, J. S.; McLeod, D.
1984-01-01
The results of vitrectomy combined with fluid/silicone-oil exchange in 73 eyes with giant retinal tears are reported at six months after surgery. Initial anatomical success was achieved in 71 out of 73 eyes (97%) and, prior to removal of silicone-oil, in 66 out of 73 eyes (90%). In 63 eyes (86%) the retina remained attached six months after surgery. Of these visual acuity was 6/60 or better in 44 (70%). The high proportion of eyes with macular detachment before surgery and the frequency of macular abnormalities are thought to account for reduced vision in many of the anatomically successful cases. PMID:6722076
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, Henry S.; Gross, Cary P.; Makarov, Danil V.
2012-08-01
Purpose: To evaluate the influence of immortal time bias on observational cohort studies of postoperative radiotherapy (PORT) and the effectiveness of sequential landmark analysis to account for this bias. Methods and Materials: First, we reviewed previous studies of the Surveillance, Epidemiology, and End Results (SEER) database to determine how frequently this bias was considered. Second, we used SEER to select three tumor types (glioblastoma multiforme, Stage IA-IVM0 gastric adenocarcinoma, and Stage II-III rectal carcinoma) for which prospective trials demonstrated an improvement in survival associated with PORT. For each tumor type, we calculated conditional survivals and adjusted hazard ratios of PORTmore » vs. postoperative observation cohorts while restricting the sample at sequential monthly landmarks. Results: Sixty-two percent of previous SEER publications evaluating PORT failed to use a landmark analysis. As expected, delivery of PORT for all three tumor types was associated with improved survival, with the largest associated benefit favoring PORT when all patients were included regardless of survival. Preselecting a cohort with a longer minimum survival sequentially diminished the apparent benefit of PORT. Conclusions: Although the majority of previous SEER articles do not correct for it, immortal time bias leads to altered estimates of PORT effectiveness, which are very sensitive to landmark selection. We suggest the routine use of sequential landmark analysis to account for this bias.« less
Patient-specific port placement for laparoscopic surgery using atlas-based registration
NASA Astrophysics Data System (ADS)
Enquobahrie, Andinet; Shivaprabhu, Vikas; Aylward, Stephen; Finet, Julien; Cleary, Kevin; Alterovitz, Ron
2013-03-01
Laparoscopic surgery is a minimally invasive surgical approach, in which abdominal surgical procedures are performed through trocars via small incisions. Patients benefit by reduced postoperative pain, shortened hospital stays, improved cosmetic results, and faster recovery times. Optimal port placement can improve surgeon dexterity and avoid the need to move the trocars, which would cause unnecessary trauma to the patient. We are building an intuitive open source visualization system to help surgeons identify ports. Our methodology is based on an intuitive port placement visualization module and atlas-based registration algorithm to transfer port locations to individual patients. The methodology follows three steps:1) Use a port placement visualization module to manually place ports in an abdominal organ atlas. This step generates port-augmented abdominal atlas. This is done only once for a given patient population. 2) Register the atlas data with the patient CT data, to transfer the prescribed ports to the individual patient 3) Review and adjust the transferred port locations using the port placement visualization module. Tool maneuverability and target reachability can be tested using the visualization system. Our methodology would decrease the amount of physician input necessary to optimize port placement for each patient case. In a follow up work, we plan to use the transferred ports as starting point for further optimization of the port locations by formulating a cost function that will take into account factors such as tool dexterity and likelihood of collision between instruments.
He, F; Zheng, L; Dong, F T
2017-05-11
Objective: To compare the effects of sterilized air and perfluoropropane (C(3)F(8)) tamponades on recovery after vitrectomy for the treatment of idiopathic full-thickness macular hole (IFTMH). Methods: Case control study. Seventy-three eyes of 69 consecutive cases underwent vitrectomy with air (53 eyes) or 10% C(3)F(8) gas (20 eyes) tamponade. Surgical outcomes were retrospectively analyzed between the two groups, including logarithm of the minimal angle of resolution (logMAR) and optical coherence tomography findings like the size of the macular hole and the photoreceptor layer defect. Results: Preoperatively, the mean best corrected visual acuity (BCVA) was (0.10±0.49), the mean hole diameter was (777.9±320.7) μm, and the mean diameter of the photoreceptor layer defect was (1 709.3±516.0) μm in the sterilized air group, while in the C(3)F(8) group, the mean BCVA was (0.07±0.50), the mean hole diameter was (853.9±355.0) μm, and the mean defect diameter was (1 480.5±429.9) μm. The primary closure rate was 90.6% in the sterilized air group and 95.0% in the C(3)F(8) group. One month after surgery, the mean BCVA was (0.17±0.41), and the mean diameter of the photoreceptor layer defect was (820.5±598.0) μm in the sterilized air group, while in the C(3)F(8) group, the mean BCVA was 0.12±0.49, and the mean defect diameter was (762.5±658.0) μm. There was no statistically significant difference in the closure rate (χ(2)=0.019), BCVA ( t =-1.689), hole diameter ( t =0.837) and diameter of the photoreceptor layer defect ( t =0.338) between the two groups( P >0.05). Conclusions: Vitrectomy with sterilized air tamponade is safe and effective for the treatment of IFTMH and even cases with relatively large diameters. (Chin J Ophthalmol, 2017, 53: 327 - 331) .
An electrostatically and a magnetically confined electron gun lens system
NASA Technical Reports Server (NTRS)
Bernius, Mark T.; Man, Kin F.; Chutjian, Ara
1988-01-01
Focal properties, electron trajectory calculations, and geometries are given for two electron 'gun' lens systems that have a variety of applications in, for example, electron-neutral and electron-ion scattering experiments. One nine-lens system utilizes only electrostatic confinement and is capable of focusing electrons onto a fixed target with extremely small divergence angles, over a range of final energies 1-790 eV. The second gun lens system is a simpler three-lens system suitable for use in a uniform, solenoidal magnetic field. While the focusing properties of such a magnetically confined lens systenm are simpler to deal with, the system does illustrate features of electron extraction and Brillouin flow that have not been suitably emphasized in the literature.
Low voltage electrowetting lenticular lens by using multilayer dielectric structure
NASA Astrophysics Data System (ADS)
Lee, Junsik; Kim, Junoh; Kim, Cheoljoong; Shin, Dooseub; Koo, Gyohyun; Sim, Jee Hoon; Won, Yong Hyub
2017-02-01
Lenticular type multi-view display is one of the most popular ways for implementing three dimensional display. This method has a simple structure and exhibits a high luminance. However, fabricating the lenticular lens is difficult because it requires optically complex calculations. 2D-3D conversion is also impossible due to the fixed shape of the lenticular lens. Electrowetting based liquid lenticular lens has a simple fabrication process compared to the solid lenticular lens and the focal length of the liquid lenticular lens can be changed by applying the voltage. 3D and 2D images can be observed with a convex and a flat lens state respectively. Despite these advantages, the electrowetting based liquid lenticular lens demands high driving voltage and low breakdown voltage with a single dielectric layer structure. A certain degree of thickness of the dielectric layer is essential for a uniform operation and a low degradation over time. This paper presents multilayer dielectric structure which results in low driving voltage and the enhanced dielectric breakdown. Aluminum oxide (Al2O3), silicon oxide (SiO2) and parylene C were selected as the multilayer insulators. The total thickness of the dielectric layer of all samples was the same. This method using the multilayer dielectric structure can achieve the lower operating voltage than when using the single dielectric layer. We compared the liquid lenticular lens with three kinds of the multilayer dielectric structure to one with the parylene C single dielectric layer in regard to operational characteristics such as the driving voltage and the dielectric breakdown.
Freysz, M; Cribier, B; Lipsker, D
2013-05-01
Port-wine stains or capillary malformations are generally congenital. Very few cases of acquired port-wine stains in adults have been described, and these occur particularly after trauma. We report three cases of acquired port-wine stains and we performed a review of the literature using the keywords "port-wine stain", "capillary malformation", "angioma" and "acquired" in the Medline database PubMed. All relevant articles were included. Two male patients and one female patient consulted for one or more angiomatous lesions, located respectively on the upper rear part of the right thigh (case 1), the left leg (case 2) and the right side of the face, skull and chest (case 3). Each patient's skin biopsy was consistent with port-wine stain. The three patients asserted the acquired nature of the lesions: the male patients were respectively 17 and 38 years old, and the female patient was 11 years old. No causative factors were evident preceding the lesion, and there was no family history of port-wine stain. The topography was systematic in patients 2 and 3. The lesions were light red in patient 1, dark red in patient 2 and pale pink in patient 3. The remainder of the physical examination was unremarkable, except for benign angiokeratoma of the scrotum in case 1 and pigmented leucoderma-type macules in case 3. LITERATURE RESULTS: Sixty-six cases of acquired port-wine stains were reported in the literature. The average age was 25 years (3-69) with a sex-ratio of 0.88. Generally, no causative factor was given. However, trauma (30.5%), estrogenic impregnation (16.5%), and more rarely, medication, solar damage, frostbite, cluster headache, herpes zoster and acoustic neuroma were reported as causatives factors. Acquired port-wine stain is rare. Although often idiopathic, it can result from spinal trauma, which must be explored if suggested by the history. In our series, the clinical presentation suggested a latent congenital vascular malformation of late onset, in particular in patients 2 and 3, because of the segmental distribution. Copyright © 2013. Published by Elsevier Masson SAS.
Two-Dimensional Computational Model for Wave Rotor Flow Dynamics
NASA Technical Reports Server (NTRS)
Welch, Gerard E.
1996-01-01
A two-dimensional (theta,z) Navier-Stokes solver for multi-port wave rotor flow simulation is described. The finite-volume form of the unsteady thin-layer Navier-Stokes equations are integrated in time on multi-block grids that represent the stationary inlet and outlet ports and the moving rotor passages of the wave rotor. Computed results are compared with three-port wave rotor experimental data. The model is applied to predict the performance of a planned four-port wave rotor experiment. Two-dimensional flow features that reduce machine performance and influence rotor blade and duct wall thermal loads are identified. The performance impact of rounding the inlet port wall, to inhibit separation during passage gradual opening, is assessed.
Fluidics comparison between dual pneumatic and spring return high-speed vitrectomy systems.
Brant Fernandes, Rodrigo A; Diniz, Bruno; Falabella, Paulo; Ribeiro, Ramiro; Teixeira, Anderson G; Magalhães, Octaviano; Moraes, Nilva; Maia, Andre; Farah, Michel E; Maia, Mauricio; Humayun, Mark S
2015-01-01
To compare the water and vitreous flow rates and duty cycle (DC) between two ultrahigh-speed vitrectomy systems: pneumatic with spring return (SR) and dual pneumatic (DP) probes. The flow rate was calculated using a high-sampling precision balance that measured the mass of water and vitreous removed from a vial by a vitreous cutter. Frame-by-frame analysis of a high-speed video of the cutter was used to determine the DC. Three cutters of each gauge (20, 23, and 25 G) were tested with an SR and a DP system using the standard DC setting (biased open) at 0 (water only), 1,000, 2,000, 3,000, 4,000, and 5,000 cuts per minute (CPM) with aspiration levels of 100, 200, 300, 400, 500, and 600 mm Hg. The DC was slightly higher with the SR system using most parameters and gauges although without statistical significance. The water flow rate was somewhat higher with the SR system, except for 25 G with 4,000 and 5,000 CPM. The vitreous flow rate was similar using most parameters, with the SR system showing higher flows at lower cut rates (1,000-3,000 CPM). SR and DP systems produced similar water and vitreous flow rates. Additional studies in human eyes are necessary to confirm these findings. Copyright 2015, SLACK Incorporated.
Innovative surgical endoscopes in video-assisted thoracic surgery
Cheng, Truman; Ng, Calvin S. H.
2018-01-01
In the past three decades, rod lens endoscopes had facilitated the development and wide spread applications of video-assisted thoracic surgery (VATS). With the rise of uniportal VATS in recent years, innovations in surgical instruments should once again complement the advancement in surgical technique. While articulated flexible endoscopes have expand the field of view, and can alter viewing direction with minimal maneuvers, they still suffer from problems like trocar crowding and interference with other instruments. Magnetic anchored endoscopes, on the other hand, may provide unique benefits to VATS by replacing the endoscope rigid rod body with magnetic linkage, thus overcoming the challenge of port crowding in single incision surgery. Most magnetic anchored endoscopes reported in literature are not designed for thoracic surgeries. Many of these designs do not allow tilting of endoscopic view, rely on micromotors for actuation, or are ergonomically unfit to be operated within the spatial constraints seen in VATS application. Considering these limitations, we have designed two novel magnetic anchored and steered endoscopes targeted for uniportal VATS. Both designs could be wirelessly actuated by magnetic interaction. One has a silicone rubber formed soft body for compactness, lightweight and safety, while another is a 40 mm long capsule optimized for VATS spatial constraints. PMID:29732196
Innovative surgical endoscopes in video-assisted thoracic surgery.
Cheng, Truman; Ng, Calvin S H; Li, Zheng
2018-04-01
In the past three decades, rod lens endoscopes had facilitated the development and wide spread applications of video-assisted thoracic surgery (VATS). With the rise of uniportal VATS in recent years, innovations in surgical instruments should once again complement the advancement in surgical technique. While articulated flexible endoscopes have expand the field of view, and can alter viewing direction with minimal maneuvers, they still suffer from problems like trocar crowding and interference with other instruments. Magnetic anchored endoscopes, on the other hand, may provide unique benefits to VATS by replacing the endoscope rigid rod body with magnetic linkage, thus overcoming the challenge of port crowding in single incision surgery. Most magnetic anchored endoscopes reported in literature are not designed for thoracic surgeries. Many of these designs do not allow tilting of endoscopic view, rely on micromotors for actuation, or are ergonomically unfit to be operated within the spatial constraints seen in VATS application. Considering these limitations, we have designed two novel magnetic anchored and steered endoscopes targeted for uniportal VATS. Both designs could be wirelessly actuated by magnetic interaction. One has a silicone rubber formed soft body for compactness, lightweight and safety, while another is a 40 mm long capsule optimized for VATS spatial constraints.
ERIC Educational Resources Information Center
Iruloh, Betty-Ruth Ngozi; Wilson, Chukwu Juliet U.
2017-01-01
The study investigated the relative relationship between family distress and eating disorders among undergraduate students of University of Port Harcourt. The study was guided by three research questions and three null hypotheses to test the tenability of the independent variables on the dependent variable at 0.05 level of significance. The study…
Flat dielectric metasurface lens array for three dimensional integral imaging
NASA Astrophysics Data System (ADS)
Zhang, Jianlei; Wang, Xiaorui; Yang, Yi; Yuan, Ying; Wu, Xiongxiong
2018-05-01
In conventional integral imaging, the singlet refractive lens array limits the imaging performance due to its prominent aberrations. Different from the refractive lens array relying on phase modulation via phase change accumulated along the optical paths, metasurfaces composed of nano-scatters can produce phase abrupt over the scale of wavelength. In this letter, we propose a novel lens array consisting of two neighboring flat dielectric metasurfaces for integral imaging system. The aspherical phase profiles of the metasurfaces are optimized to improve imaging performance. The simulation results show that our designed 5 × 5 metasurface-based lens array exhibits high image quality at designed wavelength 865 nm.
Inoue, Makoto; Abulon, Dina Joy K; Hirakata, Akito
2014-01-01
To compare the effects of different 23- and 25-gauge microincision vitrectomy trocar cannula entry systems on incision architecture. We tested one ridged microvitreoretinal (MVR), one non-ridged MVR, one pointed beveled, and one round-tipped beveled blade (n=10 per blade design per incision type). Each blade's straight and oblique incision architecture was assessed in a silicone disc simulating the sclera. Wound leakage under pressure and endoscopic observations were conducted on sclerotomy sites of isolated porcine eyes (n=4 per blade design) after simulated vitrectomy. Differences in blade design created distinct incision architecture. Incisions were linear with the ridged MVR blade, flattened "M-shaped" with the non-ridged MVR blade, asymmetrical chevron-shaped with the pointed beveled blade, and curved with the round-tipped beveled blade. With the exception of oblique entry incision thickness, both MVR blade designs created thinner incisions than the beveled blades at entry and exit sites. Only the ridged MVR blade created incisions with no leakage. Vitreous incarceration was observed with all trocar cannula systems. Wound closure in porcine eyes was similar with all blades despite differences in incision architecture. Wound leakage occurred at low to moderate infusion pressures with most blades; no wound leakage was observed with ridged MVR blades.
Inoue, Makoto; Abulon, Dina Joy K; Hirakata, Akito
2014-01-01
Purpose To compare the effects of different 23- and 25-gauge microincision vitrectomy trocar cannula entry systems on incision architecture. Methods We tested one ridged microvitreoretinal (MVR), one non-ridged MVR, one pointed beveled, and one round-tipped beveled blade (n=10 per blade design per incision type). Each blade’s straight and oblique incision architecture was assessed in a silicone disc simulating the sclera. Wound leakage under pressure and endoscopic observations were conducted on sclerotomy sites of isolated porcine eyes (n=4 per blade design) after simulated vitrectomy. Results Differences in blade design created distinct incision architecture. Incisions were linear with the ridged MVR blade, flattened “M-shaped” with the non-ridged MVR blade, asymmetrical chevron-shaped with the pointed beveled blade, and curved with the round-tipped beveled blade. With the exception of oblique entry incision thickness, both MVR blade designs created thinner incisions than the beveled blades at entry and exit sites. Only the ridged MVR blade created incisions with no leakage. Vitreous incarceration was observed with all trocar cannula systems. Conclusion Wound closure in porcine eyes was similar with all blades despite differences in incision architecture. Wound leakage occurred at low to moderate infusion pressures with most blades; no wound leakage was observed with ridged MVR blades. PMID:25429201
Alshahrani, Saeed T; Ghazi, Nicola G; Al-Rashaed, Saba
2016-01-01
To investigate the clinical findings and outcomes of rhegmatogenous retinal detachment (RRD) in Stickler syndrome on affected and fellow eyes that underwent prophylactic retinopexy. Chart review of 70 eyes (62 patients). Incidence of RRD, postoperative visual acuity, and risk factors were evaluated. Twenty-two patients (35%) had RRD in the fellow eye, 37% of the eyes had cataract, 93% had macular detachment, 50% had proliferative vitreoretinopathy, and 41% had posterior vitreous detachment. Success rates were: 60% of patients after scleral buckling; 57.1% after pars plana vitrectomy; and 75% after combined scleral buckling and pars plana vitrectomy. Sixty-one (93.8%) of patients had successful surgery (including second surgery). Silicone oil tamponade was significantly associated with final anatomic outcome, with a protective odds ratio of 0.11 (P=0.027). Visual acuity improved in 54% of eyes and decreased in 5%. Statistically significant associations were present for eyes with final visual acuity ≥20/200, and total retinal detachment (P<0.001); preoperative cataract (P=0.023); and proliferative vitreoretinopathy (P<0.001). RRD developed in 16/44 eyes despite laser prophylaxis. Prophylactic retinopexy was not beneficial for Stickler syndrome patients. Success of primary surgery for RRD remains low. The primary surgery should be vitrectomy combined with scleral buckling and silicone oil tamponade.
Anatomical and Functional Results of Lamellar Macular Holes Surgery.
Papadopoulou, D; Donati, G; Mangioris, G; Pournaras, C J
2016-04-01
To determine the long-term surgical findings and outcomes after vitrectomy for symptomatic lamellar macular holes. We studied 28 patients with lamellar macular holes and central visual loss or distortion. All interventions were standard 25 G vitrectomy with membranectomy of the internal limiting membrane (ILM), peeling and gas tamponade with SF6 20 %. Operations were performed by a single experienced surgeon within the last 3 years. Best corrected visual acuity and optical coherence tomography appearance were determined preoperatively and postoperatively. Following the surgical procedure, all macular holes were closed; however, in 3 eyes, significant foveal thinning was associated with changes in the retinal pigment epithelium changes. The mean best-corrected visual acuity improved postoperatively in the majority of the patients (n: 21, mean 0.3 logMAR), stabilised in 4 patients and decreased in 3 patients (mean 0.4 logMAR). Spectral Domain-Optical coherence tomography (SD-OCT) showed resolution of the lamellar lesion and improved macular contour in all cases. We demonstrated improvement in postoperative vision and the anatomical reconstruction of the anatomical contour of the fovea in most eyes with symptomatic lamellar holes. These findings indicate that vitrectomy, membranectomy and ILM peeling with gas tamponade is a beneficial treatment of symptomatic lamellar macular holes. Georg Thieme Verlag KG Stuttgart · New York.
Tognetto, Daniele; De Giacinto, Chiara; D'Aloisio, Rossella; Papagno, Claudia; Pastore, Marco; Zweyer, Marina
2018-01-01
To report on the combined use of trypan blue (TB) and brilliant blue G (BBG) for staining the epiretinal membrane (ERM) and internal limiting membrane (ILM) during vitrectomy and to describe the histopathological findings. 10 surgical specimens were removed from 10 eyes with macular pucker during vitrectomy using a commercially available combination of TB and BBG for ERM and ILM staining and peeling. Specimens were evaluated using light and transmission electron microscopy. In all cases the combination of TB and BBG was useful for identifying and delineating ERM and ILM. No complications related to the use of the dye were observed during or after surgery. Glial cells were present in all specimens. Hyalocytes were observed in 6 cases and myofibroblasts in 3 of them. In 7 cases native vitreous collagen fibrils were found on the ILM, while in 5 specimens newly formed collagen was present. No clinical evidence of toxicity was observed during the 3-month follow-up. The combined use of TB and BBG appeared to be very useful intraoperatively to improve the visualization of ERM and ILM, thus facilitating their complete removal. Anatomical and histopathological findings demonstrated the safety and the efficacy of this vital dye. © 2018 S. Karger AG, Basel.
Ocular oxygen consumption: estimates using vitreoperfusion in the cat.
Blair, Norman P; Liu, Ting; Warren, Keith A; Glaser, David A; Kennedy, Marc; Tran, Huan; Larson, Christopher A; Atluri, Prasant; Saidel, Michael A; Blair, Michael P
2004-02-01
Little is known about the ocular oxygen consumption rate (QO2) in human diseases. Alterations in QO2 must occur in many conditions, such as retinal ischemia. We present a method of estimating QO2 that eventually could be used in patients during vitrectomy surgery. We performed vitreoperfusion (i.e., perfusion of the vitreous cavity after vitrectomy) in 14 cat eyes with no ocular blood flow. The solution contained nutrients at a high partial pressure of oxygen (PO2). In eight eyes, the retinas were undisturbed (Group 1), and in six eyes, we excised the retinas (Group 2). We estimated QO2 in both groups on the basis of the temporal decline of PO2 in the vitreoperfusion solution according to a pharmacokinetic model. The mean and standard deviation of QO2 was 3.2 +/- 0.8 microL/min in Group 1 and 0.4+/- 0.7 microL/min in Group 2, with the difference being the retinal contribution, 88%. In Group 1, metabolism, bulk flow, and diffusion accounted for 82, 13, and 5%, respectively, of the oxygen loss from the vitreoperfusion solution. We estimated ocular oxygen consumption by means of vitreoperfusion. Eventually, the pathophysiology of human diseases may be clarified by similar measurements during vitrectomy.
Choi, A Young; Cho, Hochan; Kim, Yu Cheol
2018-01-01
This study aims to compare the efficacy and safety between two different doses of intravitreal bevacizumab (IVB) injection with temporal retina-sparing laser (TRSL) photocoagulation for retinopathy of prematurity (ROP). We retrospectively evaluated 22 eyes of ROP infants who underwent IVB combined with partial TRSL for stage 3+ zone I or posterior zone II ROP. Laser photocoagulation was applied on the avascular retina, sparing two-disc-diameter width temporal avascular area anterior to ridge. A half dose (0.625 mg) or minimal dose (0.25 mg) of IVB was conducted. Four eyes in minimal dose group were retreated with IVB and laser photocoagulation on the spared retina. Of those 4 retreated eyes, three developed preretinal hemorrhage around the ridge after the first treatment, resulting in fibrotic macular dragging. A half dose of IVB may be more effective than a minimal dose with partial TRSL for ROP. Preretinal hemorrhage may be a harbinger of poor prognosis.
On-chip remote charger model using plasmonic island circuit
NASA Astrophysics Data System (ADS)
Ali, J.; Youplao, P.; Pornsuwancharoen, N.; Aziz, M. S.; Chiangga, S.; Amiri, I. S.; Punthawanunt, S.; Singh, G.; Yupapin, P.
2018-06-01
We propose the remote charger model using the light fidelity (LiFi) transmission and integrate microring resonator circuit. It consists of the stacked layers of silicon-graphene-gold materials known as a plasmonic island placed at the center of the modified add-drop filter. The input light power from the remote LiFi can enter into the island via a silicon waveguide. The optimized input power is obtained by the coupled micro-lens on the silicon surface. The induced electron mobility generated in the gold layer by the interfacing layer between silicon-graphene. This is the reversed interaction of the whispering gallery mode light power of the microring system, in which the generated power is fed back into the microring circuit. The electron mobility is the required output and obtained at the device ports and characterized for the remote current source applications. The obtained calculation results have shown that the output current of ∼2.5 × 10-11 AW-1, with the gold height of 1.0 μm and the input power of 5.0 W is obtained at the output port, which is shown the potential application for a short range free pace remote charger.
Lee, Jin Young; Sung, Kyung Rim; Tchah, Hung Won; Yoon, Young Hee; Kim, June Gone; Kim, Myoung Joon; Kim, Jae Yong; Yun, Sung-Cheol; Lee, Joo Yong
2012-12-01
To evaluate whether a combination of penetrating keratoplasty (PKP) or pars plana vitrectomy (PPV) and Ahmed glaucoma valve (AGV) implantation affords a level of success similar to that of AGV implantation alone. Eighteen eyes underwent simultaneous PPV and AGV, 14 eyes with PKP and AGV and 30 eyes with AGV implantation alone were evaluated. Success was defined as attainment of an intraocular pressure (IOP) >5 and <22 mmHg, with or without use of anti-glaucoma medication. Kaplan-Meier survival analysis was performed to compare cumulative survival between the combined surgery groups and the AGV implantation-alone group. Cox proportional hazard regression analysis was conducted to identify factors predictive of success in each of the three groups. Mean (±standard deviation) preoperative IOP was 30.2 ± 10.2 mmHg in the PKP + AGV, 35.2 ± 9.8 mmHg in the PPV + AGV, and 36.2 ± 10.1 mmHg in the AGV implantation-alone group. The cumulative success rate at 18 months was 66.9%, 73.2%, and 70.8% in the three groups, respectively. Neither combined surgery group differed significantly in terms of cumulative success rate compared with the AGV implantation-alone group (p = 0.556, p = 0.487, respectively). The mean number of preoperative anti-glaucoma medications prescribed was significantly associated with success in the PKP + AGV implantation group (hazard ratio, 2.942; p = 0.024). Either PKP or PPV performed in conjunction with AGV implantation afforded similar success rates compared to patients treated with AGV implantation alone. Therefore, in patients with refractory glaucoma who have underlying corneal or retinal pathology requiring treatment with PKP or PPV, AGV implantation can be performed simultaneously.
Sayman Muslubas, Isil; Karacorlu, Murat; Hocaoglu, Mumin; Ersoz, Mehmet Giray; Arf, Serra
2018-03-01
Our purpose was to assess anatomical and functional outcomes of vitrectomy in pediatric cases of Terson syndrome. A total of 11 eyes of seven children diagnosed with Terson syndrome secondary to traumatic brain injury and 17 eyes of 12 children diagnosed with Terson syndrome secondary to nontraumatic brain hemorrhage who had 20-gauge or 23-gauge pars plana or pars plicata vitrectomy were included in this retrospective study. The primary outcome was the change in visual acuity from the preoperative examination to postoperative final follow-up. Secondary outcomes were anatomic surgical success and postoperative complications. The mean time between diagnosis and surgery was 62 ± 35 days (range, 30-150), and the average age at the time of the surgery was 4.5 ± 6.4 years (range, 3 months to 17 years). The mean preoperative logarithm of the minimum angle of resolution (logMAR) (Snellen) best corrected visual acuity (BCVA) was 2.6 ± 0.7 (20/7260) (n = 9) and in the remaining 19 eyes it was recorded as noncentral, unsteady, nonmaintained fixation. The mean follow-up period was 50 ± 54 months (range, 12-192 months). At the last follow-up visit, the mean logMAR BCVA was 0.46 ± 0.6 (20/60) (n = 19) and in eight eyes it was recorded as fix-and-follow. One eye developed a retinal detachment 14 months after the first operation, and one eye developed an epiretinal membrane after 2 years. Anatomical success was recorded in all patients at the final visit. In children with massive vitreous hemorrhage secondary to Terson syndrome, vitrectomy is an effective procedure and offers a rapid visual improvement. Earlier surgical treatment prevents amblyopia and blood-related potential complications.
Holographic zoom system based on spatial light modulator and liquid device
NASA Astrophysics Data System (ADS)
Wang, Di; Li, Lei; Liu, Su-Juan; Wang, Qiong-Hua
2018-02-01
In this paper, two holographic zoom systems are proposed based on the programmability of spatial light modulator (SLM) and zoom characteristics of liquid lens. An active optical zoom system is proposed in which the zoom module is composed of a liquid lens and an SLM. By controlling the focal lengths of the liquid lens and the encoded digital lens on the SLM, we can change the magnification of an image without mechanical moving parts and keep the output plane stationary. Then a color holographic zoom system based on a liquid lens is proposed. The system processes the color separation of the original object for red, green, and blue components and generated three holograms respectively. A new hologram with specific reconstructed distance can be generated by combing the hologram of the digital lens with the hologram of the image. By controlling the focal lengths of the liquid lens and the encoded digital lens on the SLM, we can change the magnification of the reconstructed image.
Development of an Implantable Fish Spawning Sensor Tag
2013-09-24
Manatee Hatchery Facility, Port Manatee , Florida) using a Millar Instruments pressure catheter inserted a fixed distance (15cm) into the ovary before and...red drum aquaculture facility in Port Manatee , Florida (or similar aquaculture facility where spawning fishes are kept). This facility maintains a...at the Port Manatee hatchery and phase three tests on goliath grouper in the field. RESULTS *Please refer to other sections for more details and
Code of Federal Regulations, 2012 CFR
2012-07-01
....22″ W (NAD 83). 7.33Clam Shell Foundation Fireworks • Location: Waters of Three Mile Harbor, East..., Air Shows and Swim Events in the Captain of the Port Long Island Sound Zone. 165.151 Section 165.151... Swim Events in the Captain of the Port Long Island Sound Zone. (a) Regulations. (1) The general...
de Freitas, Carolina; Ruggeri, Marco; Manns, Fabrice; Ho, Arthur; Parel, Jean-Marie
2013-01-15
We present a method for measuring the average group refractive index of the human crystalline lens in vivo using an optical coherence tomography (OCT) system which, allows full-length biometry of the eye. A series of OCT images of the eye including the anterior segment and retina were recorded during accommodation. Optical lengths of the anterior chamber, lens, and vitreous were measured dynamically along the central axis on the OCT images. The group refractive index of the crystalline lens along the central axis was determined using linear regression analysis of the intraocular optical length measurements. Measurements were acquired on three subjects of age 21, 24, and 35 years. The average group refractive index for the three subjects was, respectively, n=1.41, 1.43, and 1.39 at 835 nm.
Demonstration of arbitrary views based on autostereoscopic three-dimensional display system
NASA Astrophysics Data System (ADS)
Liu, Boyang; Sang, Xinzhu; Yu, Xunbo; Li, Liu; Yang, Le; Yan, Binbin; Wang, Kuiru; Yu, Chongxiu
2017-10-01
A method to realize arbitrary views for the lenticular lens array based on autostereoscopic three-dimensional display system is demonstrated. Normally, the number of views is proportional to pitch of the lenticular lens array. Increasing the number of views will result in reducing resolution and enhancing of granular sensation. 32 dense views can be achieved with one lenticular lens pitch covering 5.333 sub-pixels, which does significantly increases the number of views without affecting the resolution. But the structure of pitch and the number of views are fixed. Here, the 3D display method that the number of views can be changed artificially for most structures of lenticular lens is presented. Compared with the previous 32 views display method, the smoothness of motion parallex and the display depth of field are significantly improved.
NASA Astrophysics Data System (ADS)
Zhang, Wei; Liu, Pengfei; Wei, Xiaona; Zhuang, Songlin; Yang, Bo
2010-11-01
Liquid lens is a novel optical device which can implement active zooming. With liquid lens, zoom camera can be designed with more miniature size and simpler structure than before. It is thought that the micro zoom system with liquid lens has a very wide potential applications in many fields, in which the volume and weight of the system are critically limited, such as endoscope, mobile, PDA and so on. There are mainly three types of tunable-focus liquid lens: liquid crystal lens, electrowetting effect based liquid lens and liquid-filled membrane lens. Comparing with the other two kinds of liquid lens, the liquid-filled membrane lens has the advantages of simple structure, flexible aperture and high zooming efficiency. But its membrane surface will have an initial shape deformation caused by the gravity when the aperture of the lens is at large size, which will lead to the wave front aberration and the imaging quality impairing. In this paper, the initial deformation of the lens caused by the gravity was simulated based on the theory of Elastic Mechanics, which was calculated by the Finite Element Analysis method. The relationship between the diameter of the lens and the wave front aberration caused by the gravity was studied. And the Optical path difference produced by different liquid density was also analyzed.
Acanthamoeba keratitis in patients wearing scleral contact lenses.
Sticca, Matheus Porto; Carrijo-Carvalho, Linda C; Silva, Isa M B; Vieira, Luiz A; Souza, Luciene B; Junior, Rubens Belfort; Carvalho, Fábio Ramos S; Freitas, Denise
2018-06-01
To report a series of cases of Acanthamoeba keratitis (AK) in scleral lens wearers with keratoconus to determine whether this type of contact lens presents a greater risk for development of infection. This study reports three patients who wore scleral contact lenses to correct keratoconus and developed AK. The diagnoses of AK were established based on cultures of the cornea, scleral contact lenses, and contact lens paraphernalia. This study investigated the risk factors for infections. The possible risks for AK in scleral contact lens wearers are hypoxic changes in the corneal epithelium because of the large diameter and minimal tear exchange, use of large amounts of saline solution necessary for scleral lens fitting, storing the scleral lens overnight in saline solution rather than contact lens multipurpose solutions, not rubbing the contact lens during cleaning, and the space between the cornea and the back surface of the scleral lens that might serve as a fluid reservoir and environment for Acanthamoeba multiplication. Two patients responded well to medical treatment of AK; one is still being treated. The recommendations for use and care of scleral contact lenses should be emphasized, especially regarding use of sterile saline (preferably single use), attention to rubbing the lens during cleaning, cleaning of the plunger, and overnight storage in fresh contact lens multipurpose solutions without topping off the lens solution in the case. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
Analysis of laparoscopic port site complications: A descriptive study
Karthik, Somu; Augustine, Alfred Joseph; Shibumon, Mundunadackal Madhavan; Pai, Manohar Varadaraya
2013-01-01
CONTEXT: The rate of port site complications following conventional laparoscopic surgery is about 21 per 100,000 cases. It has shown a proportional rise with increase in the size of the port site incision and trocar. Although rare, complications that occur at the port site include infection, bleeding, and port site hernia. AIMS: To determine the morbidity associated with ports at the site of their insertion in laparoscopic surgery and to identify risk factors for complications. SETTINGS AND DESIGN: Prospective descriptive study. MATERIALS AND METHODS: In the present descriptive study, a total of 570 patients who underwent laparoscopic surgeries for various ailments between August 2009 and July 2011 at our institute were observed for port site complications prospectively and the complications were reviewed. STATISTICAL ANALYSIS USED: Descriptive statistical analysis was carried out in the present study. The statistical software, namely, SPSS 15.0 was used for the analysis of the data. RESULTS: Of the 570 patients undergoing laparoscopic surgery, 17 (3%) had developed complications specifically related to the port site during a minimum follow-up of three months; port site infection (PSI) was the most frequent (n = 10, 1.8%), followed by port site bleeding (n = 4, 0.7%), omentum-related complications (n = 2; 0.35%), and port site metastasis (n = 1, 0.175%). CONCLUSIONS: Laparoscopic surgeries are associated with minimal port site complications. Complications are related to the increased number of ports. Umbilical port involvement is the commonest. Most complications are manageable with minimal morbidity, and can be further minimized with meticulous surgical technique during entry and exit. PMID:23741110
The Role of Aquaporins in Ocular Lens Homeostasis
Schey, Kevin L.; Petrova, Rosica S.; Gletten, Romell B.; Donaldson, Paul J.
2017-01-01
Aquaporins (AQPs), by playing essential roles in the maintenance of ocular lens homeostasis, contribute to the establishment and maintenance of the overall optical properties of the lens over many decades of life. Three aquaporins, AQP0, AQP1 and AQP5, each with distinctly different functional properties, are abundantly and differentially expressed in the different regions of the ocular lens. Furthermore, the diversity of AQP functionality is increased in the absence of protein turnover by age-related modifications to lens AQPs that are proposed to alter AQP function in the different regions of the lens. These regional differences in AQP functionality are proposed to contribute to the generation and directionality of the lens internal microcirculation; a system of circulating ionic and fluid fluxes that delivers nutrients to and removes wastes from the lens faster than could be achieved by passive diffusion alone. In this review, we present how regional differences in lens AQP isoforms potentially contribute to this microcirculation system by highlighting current areas of investigation and emphasizing areas where future work is required. PMID:29231874