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Age-related macular degeneration (AMD) is one of the leading causes of blindness in the industrialized world, affecting over 8 million patients in the United State alone. While the wet (exudative) form of the disease is treated with intraocular injections, there are currently no approved therapies available for the dry (non-exudative) form of the disease which often affects both eyes in patients with AMD. Current research has focused on developing drugs that can be injected into the eye, but the treatment burden associated with monthly injections limits the effectiveness of this approach. Hence, there is a pressing need for a long-term therapeutic solution for patients suffering from this blinding disease. We detail a novel implantable intraocular device, which adsorbs and traps complement factors associated with AMD. In this study, we tested a novel approach by dialyzing proteins from the vitreous using biocompatible implants composed of a nanopore polyacrylonitrile polymer membrane. Preliminary in vitro and in vivo studies demonstrate a high affinity and capacity for complement protein absorption. After a three-month implantation in New Zealand White Cross rabbits, the implant demonstrated good biocompatibility with no inflammation and normal retinal physiology and histology. These studies demonstrate that prolonged CF suppression intraocularly may be accomplished with a nanopore polymer membrane.

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PURPOSE: Corneal transplant rejection is one of the most frequent complications, with a reported incidence of 16-30%. In our current research, we investigated the use of infrared thermography to detect ocular surface temperature. We also looked at a case of corneal transplant rejection and this case had an elevated ocular surface temperature when compared to the contralateral eye and other eyes without corneal transplant rejection. METHODS: Twenty-three eyes of twelve patients would serve as control to one eye with clinically evident corneal transplant graft rejection. A Flir T400 320 × 240 pixel, digital thermal camera was used to take a digital photograph and an infrared photograph of each eye. The images were analyzed with the Flir web viewer. RESULTS: We present here a case of corneal transplant rejection documented with both slit lamp photos as well as infrared and corneal surface photos. The studied patient's unaffected eye, and the control group's trends did indeed bring the expected results and proved thermal imagery in this particular field a viable examination method. CONCLUSIONS: We feel that ocular thermography is a useful adjunctive diagnostic tool and that it may be useful to monitor routine corneal transplant patients. Further research into the temperature changes of corneal transplant patients is needed and may allow for earlier intervention for graft rejection.

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PURPOSE: To describe management of posteriorly retained iris expansion ring-a newly reported complication of phacoemulsification surgery in a patient with intact posterior capsule. METHODS: Case report. PATIENTS: A 64-year-old monocular patient with history of regressed proliferative diabetic retinopathy after pars plana vitrectomy, long-standing glaucoma, and cataract, undergoing phacoemulsification for cataract removal, complicated by posterior migration of the Malyugin ring through area of zonular dehiscence despite intact posterior capsule, which resulted in significant visual disturbance. RESULTS: The intravitreal Malyugin ring was successfully removed by performing a standard 3-port 25-gauge vitrectomy and retrieving the mobilized ring into the barrel of the original injector device. CONCLUSION: A posteriorly retained iris expansion ring can be effectively extracted from the vitreous cavity with the original injector device, which allows for maximal control of the ring and minimal associated surgical trauma.

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PURPOSE: To assess the change in ocular surface temperature between healthy phakic and pseudophakic patients. METHODS: We included patients with no history of ocular disease other than cataract. Patients were divided into three groups: clear lens, cataract, and pseudophakic. All patients had two ocular surface digital thermal scans. An average of five surface points was used as the mean ocular surface temperature. Results were analyzed with a one-way analysis of variance and a Tukey's least significance difference test. The patients were further divided into phakic and pseudophakic groups. Correlation coefficients between several variables were done in order to assess dependencies. RESULTS: Fifty-six eyes (28 cataracts, 12 clear lenses, 16 pseudophakic) were enrolled. The mean ocular surface temperature in the cataract group was 34.14°C±1.51°C; clear lens: 34.43°C±2.27°C; and pseudophakic: 34.97°C±1.57°C. There were no statistical differences among the study groups (P=0.3). There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group. The trend inverted in the pseudophakic group but without statistical significance. CONCLUSION: Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant.

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UNLABELLED: We describe a surgical technique for scleral fixation of a posterior chamber intraocular lens (PC IOL) using a 24-gauge injectable polypropylene suture delivery system. A 3-piece PC IOL is inserted into the anterior chamber of the eye. Two sclerotomies are made 1.5 mm posterior to the limbus using a microvitreoretinal blade. The 24-gauge injector delivers a preformed suture loop into the eye with the double-armed needles still external to the eye. Each polypropylene IOL haptic is directed through the loop using microforceps. The suture loop is tightened around the haptic, and the attached needles are used to fixate the IOL to the sclera and close the sclerotomies simultaneously. This technique has been used in an ex vivo porcine eye and in an aphakic patient. In the latter, the IOL was quickly fixated to the sclera and maintained a stable position postoperatively. FINANCIAL DISCLOSURE: Dr. Olson has a patent pending for the device described in this article. No other author has a financial or proprietary interest in any material or method mentioned.

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A 91-year old man with a history of senile cataract and chronic lymphocytic leukemia (CLL), with a platelet count of 75,000/µL, presented for phacoemulsification and intraocular lens implantation in the left eye. A paracentesis made at the beginning of the procedure caused a small but not unusual amount of anterior chamber decompression. Spontaneous bleeding subsequently occurred from multiple sights on the iris surface. The bleeding was stopped by injecting hyaluronic acid into the anterior chamber to increase intraocular pressure. The remainder of the procedure was performed without complication, and resulting visual acuity improved from 20/70 preoperatively to 20/20(-2) with refraction 1 week postoperatively. In previously reported cases of intraocular bleeding during cataract surgery in thrombocytopenic patients, platelet counts were all ≤55,000/µL.

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PURPOSE: To compare the differences in the time of completion of cataract surgery for residents and attending surgeons and to assign a dollar cost. SETTING: University of Colorado teaching hospital, Aurora, Colorado, USA. DESIGN: Comparative case series. METHODS: Cataract cases were divided into 3 levels of difficulty for comparison. Main outcome measures were total case time (incision to patch) and degree of difficulty. RESULTS: Nine residents and 6 attending surgeons participated in the study. Case times were collected for 324 resident cases and 319 attending surgeon cases. The mean attending surgeon case time was 25.75 minutes ± 12.32 (SD) and the mean resident case time, 46.35 ± 16.75 minutes. There was no significant difference in the degree of difficulty between resident cases and attending surgeon cases. Approximately 600 total cases were performed by 4 residents during 3 years of residency training. Taking into account the mean time of case completion for attending surgeons versus residents, the total difference in time if attending surgeons had performed 600 cataracts would be 12,360 minutes. Using a dollar cost of approximately $11.24 per minute at the institution, the cost difference was calculated to be $138,926.40. CONCLUSION: There was a significant time and dollar cost incurred in teaching cataract surgery. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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BACKGROUND AND OBJECTIVE: To describe a suction-based grasping tool for the surgical removal of irregular-shaped and nonferromagnetic intraocular foreign bodies. MATERIALS AND METHODS: A surgical tool with suction capabilities, consisting of a stainless steel shaft with a plastic handle and a customizable and interchangeable suction tip, was designed in order to better engage and manipulate irregular-shaped in-traocular foreign bodies of various sizes and physical properties. The maximal suction force and surgical capabilities were assessed in the laboratory and on a cadaveric eye vitrectomy model. RESULTS: The suction force of the water-tight seal between the intraocular foreign body and the suction tip was estimated to be approximately 40 MN. During an open-sky vitrectomy in a porcine model, the device was successful in engaging and firmly securing foreign bodies of different sizes and shapes. CONCLUSION: The suction-based grasping tool enables removal of irregular-shaped and nonferromagnetic foreign bodies.

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UNLABELLED: Spontaneous late subluxation of an intraocular lens (IOL) is a rare but serious complication of cataract surgery, often associated with poor zonular support. The management of this complication with a conventional forceps is difficult because the forceps often cannot adequately grasp the optic or haptic to fixate the IOL to the sclera or iris or remove it. The new suction-based grasping tool has a suction cup at the end. The combination of a suction vector and the use of a set of specially designed suction tips allow grasping and stabilization of the subluxated IOL. The properties of the suction-based grasping tool provide better control of the subluxated IOL, simplifying the management of these challenging cases. FINANCIAL DISCLOSURE: Drs. Olson and Mackenzie have a patent application pending for the disclosed device. No other author has a financial or proprietary interest in any material or method mentioned.

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PURPOSE: To describe a novel surgical technique and novel surgical instrumentation for fixating an extraocular drainage device used for glaucoma-filtering surgery. MATERIALS AND METHODS: The technique was performed in a laboratory setting using ex-vivo porcine eyes. We describe the surgical technique of using injectable, 25-gauge shape-memory clip system to fixate an Ahmed drainage device. RESULTS: The use of an injectable, shape-memory alloy clip provides the advantages of rapid, easy deployment and decreased risk of late suture failure. Importantly, the injectable, shape-memory clips can be used in surgical situations where suturing is difficult and time intensive, such as those encountered during glaucoma drainage device placement. CONCLUSIONS: The use of an injectable, shape-memory alloy clip is a promising new surgical tool and technique for fixating an extraocular drainage device used for glaucoma surgery.

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This case report describes the clinical, autofluorescence, and optical coherent tomography findings in a patient with panocular argyrosis secondary to chronic intake of diluted silver nitrate salts in his water supply. An 86-year-old Caucasian male with a distinctive gray-bluish hue of the skin presented to our clinic, having developed a slow decrease in visual acuity in both eyes and nyctalopia for the past 2 years. Based on the patient's history of chronic intake of silver nitrate salts and a positive skin biopsy (performed by the dermatology department, data not shown), a diagnosis of panocular argyrosis was made. Fluorescein angiography showed choroidal blockage with a completely dark choroid. Fundus autofluorescence was within normal limits. Optical coherent tomography showed multiple excrescences of retinal pigment epithelium in both eyes. Although the drusen-like changes on fundus examination and retinal pigment epithelium changes may account for the diminished vision, the presence of concomitant nyctalopia suggests underlying damage of the photoreceptors.

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A novel surgical technique and novel surgical instrumentation for closing a pupil defect in a closed chamber eye is described. The technique was performed in a laboratory setting using ex-vivo porcine eyes using a 30-gauge deployment system to repair iris defects. Given the difficulty of suturing in a closed chamber eye, the use of an injectable, shape memory alloy clip offers the advantages of rapid, easy deployment and increased strength over conventional suture techniques.

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Suturing in space-confined surgical settings encountered during microsurgical procedures can be technically complex and time intensive. This paper presents the development of a new injector and new shape-memory alloy clip that can replace conventional suture. Engineering and surgical assessments of the injector and clips were performed. A prototype of the delivery system was tested in simulated surgical settings and compared to conventional suturing techniques for surgical time and wound strength. In various micro-surgical scenarios, the new injectable system proved to be 5 to 20-times more efficient and to have wound strengths over three-times that of conventional suturing. Further, the wounds closed by the shape-memory alloy clips could be forced to open and then recover to a watertight state, unlike conventional sutures which break upon failure. This new injector and shape-memory alloy clips proved to be quicker, stronger, and technically easier than conventional suturing. Future work is underway to test the injectable delivery system and the shape-memory alloy clips using a real-time, in vivo porcine model.

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PURPOSE: To evaluate the tolerance and biocompatibility of a preformed nitinol intraocular clip in an animal model after anterior segment surgery. METHODS: Yucatan mini-pigs were used. A 30-gauge prototype injector was used to attach a shape memory nitinol clip to the iris of five pigs. Another five eyes received conventional polypropylene suture with a modified Seipser slip knot. The authors compared the surgical time of each technique. All eyes underwent standard full-field electroretinogram at baseline and 8 weeks after surgery. The animals were euthanized and eyes collected for histologic analysis after 70 days (10 weeks) postsurgery. The corneal thickness, corneal endothelial cell counts, specular microscopy parameters, retina cell counts, and electroretinogram parameters were compared between the groups. A two sample t-test for means and a P value of 0.05 were use for assessing statistical differences between measurements. RESULTS: The injection of the nitinol clip was 15 times faster than conventional suturing. There were no statistical differences between the groups for corneal thickness, endothelial cell counts, specular microscopy parameters, retina cell counts, and electroretinogram measurements. CONCLUSIONS: The nitinol clip prototype is well tolerated and showed no evidence of toxicity in the short-term. The injectable delivery system was faster and technically less challenging than conventional suture techniques.

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PURPOSE: To characterize how residents learn phacoemulsification and determine which steps of the procedure are most difficult to master. SETTING: University of Colorado Hospital, Aurora, Colorado, USA. DESIGN: Comparative case series. METHODS: Cataract cases were divided into 3 levels of difficulty for comparison. Residents were given a grade for each step of the procedure by the attending surgeon. Main outcome measures were total case time and a proficiency grade. Independent variables were level of resident experience and degree of difficulty. Case times of attending cases were collected for comparison. RESULTS: Nine residents were evaluated by 4 attending surgeons while performing 324 cases of phacoemulsification. Case times of 319 attending cases were used for comparison. The easiest-to-learn steps (highest scores versus level of experience) included intraocular lens insertion, ophthalmic viscosurgical device removal, hydrodissection, and nucleus sculpting. Wound integrity, nucleus disassembly and removal, cortex removal, and capsulorhexis had the lowest scores versus level of experience. Resident case times decreased significantly with experience, approaching average case times for attendings. CONCLUSIONS: For this study, competency was defined as the ability of the resident to perform a case in a reasonable time without intervention or complication. Using this definition, competency was achieved when case experience exceeded 75 cataract surgeries. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

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Plasmodesmal conductivity is regulated in part by callose turnover, which is hypothesized to be determined by beta-1,3-glucan synthase versus glucanase activities. A proteomic analysis of an Arabidopsis thaliana plasmodesmata (Pd)-rich fraction identified a beta-1,3-glucanase as present in this fraction. The protein encoded by the putative plasmodesmal associated protein (ppap) gene, termed AtBG_ppap, had previously been found to be a post-translationally modified glycosylphosphatidylinositol (GPI) lipid-anchored protein. When fused to green fluorescent protein (GFP) and expressed in tobacco (Nicotiana tabacum) or Nicotiana benthamiana epidermal cells, this protein displays fluorescence patterns in the endoplasmic reticulum (ER) membrane system, along the cell periphery and in a punctate pattern that co-localizes with aniline blue-stained callose present around the Pd. Plasma membrane localization was verified by co-localization of AtBG_ppap:GFP together with a plasma membrane marker N-[3-triethylammoniumpropyl]-4-[p-diethylaminophenylhexatrienyl] pyridinium dibromide (FM4-64) in plasmolysed cells. In Arabidopsis T-DNA insertion mutants that do not transcribe AtBG_ppap, functional studies showed that GFP cell-to-cell movement between epidermal cells is reduced, and the conductivity coefficient of Pd is lower. Measurements of callose levels around Pd after wounding revealed that callose accumulation in the mutant plants was higher. Taken together, we suggest that AtBG_ppap is a Pd-associated membrane protein involved in plasmodesmal callose degradation, and functions in the gating of Pd.

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PURPOSE: To describe the use of a tarsoconjunctival pedicle flap for the repair of a large scleral melt in a patient with rheumatoid arthritis. METHODS: Case report and literature review. RESULTS: A 36-year-old woman with a history of rheumatoid arthritis presented to the Rocky Mountain Lions Eye Institute with a large scleral melt in the right eye. Ophthalmic examination revealed a visual acuity of 20/400 and a superior scleral melt measuring 15 x 30 mm. After instituting systemic immunosuppression, a tarsoconjunctival pedicle was used to provide tectonic support to the globe. At her 3-month postoperative visit, her vision improved to 20/30, and the scleral melt was completely epithelialized. CONCLUSIONS: A tarsoconjunctival pedicle flap provides an excellent alternative to help restore scleral integrity in patients with severe autoimmune necrotizing scleritis.

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