Open-angle glaucoma and Fuchs dystrophy.

A 62-year-old woman with a history of moderate myopia, long-standing open-angle glaucoma (OAG), and Fuchs dystrophy in both eyes was referred for consultative care. She had prior trabeculectomy in 1984 and 1992 in the left and right eyes, respectively. She is 3 months post-Descemet-stripping endothelial keratoplasty (DSEK) in the left eye, now referred with uncontrolled intraocular pressure (IOP) despite maximum tolerated medical therapy. Current medical therapy for IOP consists of acetazolamide 250 mg by mouth 2 times a day, brimonidine 2 times a day in the left eye, dorzolamide 2 times a day in the left eye, and timolol 2 times a day in the left eye. The patient has a history of presumed steroid response; however, her corneal surgeon has requested that the steroid be continued for the next several months because of the recent DSEK. The IOP in the left eye has ranged from the mid-20s to mid-30s since DSEK. The right eye has consistently had pressure in the low teens and below for many years without topical antihypertensive medications. Examination revealed stable visual acuity at 20/30 and 20/40 in the right and left eyes, respectively, IOP was 12 mm Hg in the right eye and 25 mm Hg in the left eye by Goldman applanation, irregular but reactive pupils without afferent defect, and full confrontational visual fields. Slitlamp examination showed superior low avascular bleb, moderate-to-severe guttae, and posterior chamber IOL in the right eye. The left eye showed superior low diffuse bleb, clear DSEK graft, quiet chamber, superonasal iridectomy, and posterior chamber IOL with an open posterior capsule. The conjunctiva was moderately scarred but a repeat trabeculectomy or Xen Gel stent (Abbvie) appeared possible. The angles were wide open in each eye. Fundus examination was normal aside from myopic, anomalous-appearing nerves with an approximate cup-to-disc ratio of 0.90 in both eyes. Humphrey visual field showed nonspecific changes on the right and moderate nasal defect on the left eye, stable to previous examinations dating back to 2018 (Figure 1JOURNAL/jcrs/04.03/02158034-202407000-00018/figure1/v/2024-07-10T174240Z/r/image-tiff and Figure 2JOURNAL/jcrs/04.03/02158034-202407000-00018/figure2/v/2024-07-10T174240Z/r/image-tiff). Optical coherence tomography (OCT) of the retinal nerve fiber layer (RNFL) revealed moderated thinning in both eyes that was also stable to prior examinations (Figure 3JOURNAL/jcrs/04.03/02158034-202407000-00018/figure3/v/2024-07-10T174240Z/r/image-tiff). Her axial length measured 25.23 and 26.34 mm in the right and left eyes, respectively. Central corneal thickness was 553 µm in the right eye and 563 µm in the left eye before her DSEK procedure. What would be your approach to management of this patient's left eye, addressing the following: Rationale for your procedure of choice? Would you over-rule the corneal surgeon and stop the steroid in an attempt to obviate the need for glaucoma surgery? Does the age of onset of glaucoma affect your surgical decision making? Note that patient age at the time of trabeculectomy was 22 years. Are some procedures better suited for patients after DSEK surgery?

Fabrication of a glucose biosensor based on citric acid assisted cobalt ferrite magnetic nanoparticles.

A novel and practical glucose biosensor was fabricated with immobilization of Glucose oxidase (GOx) enzyme on the surface of citric acid (CA) assisted cobalt ferrite (CF) magnetic nanoparticles (MNPs). This innovative sensor was constructed with glassy carbon electrode which is represented as (GOx)/CA-CF/(GCE). An explicit high negative zeta potential value (-22.4 mV at pH 7.0) was observed on the surface of CA-CF MNPs. Our sensor works on the principle of detection of H2O2 which is produced by the enzymatic oxidation of glucose to gluconic acid. This sensor has tremendous potential for application in glucose biosensing due to the higher sensitivity 2.5 microA/cm2-mM and substantial increment of the anodic peak current from 0.2 microA to 10.5 microA.

Wet-chemical green synthesis of L-lysine amino acid stabilized biocompatible iron-oxide magnetic nanoparticles.

In this paper, we report a novel method for the synthesis of L-Lysine (lys) amino acid coated maghemite (gamma-Fe2O3) magnetic nanoparticles (MNPs). The facile and cost effective method permitted preparation of the high-quality superparamagnetic gamma-Fe2O3 MNPs with hydrophilic and biocompatible nature. For this work, first we synthesized magnetite phase Fe3O4/lys by wet chemical method and oxidized to y-Fe2O3 in controlled oxidizing environment, as evidenced by XRD and VSM magnetometry. The crystallite size and magnetization of gamma-Fe2O3/lys MNPs was found to be 14.5 nm, 40.6 emu/gm respectively. The surface functionalization by L-lysine amino acid and metal-ligand bonding was also confirmed by FTIR spectroscopy. The hydrodynamic diameter, colloidal stability and surface charge on MNPs were characterized by DLS and zeta potential analyser.

Comparison of Proview phosphene tonometry with Goldmann applanation tonometry.

BACKGROUND: To compare intraocular pressures obtained using a handheld pressure phosphene tonometer (PPT) (Proview, Bausch & Lomb Pharmaceuticals, Inc., Tampa, Fla.) with Goldmann applanation tonometry. METHODS: Comparative case series of 30 randomly selected patients. RESULTS: The readings obtained with the pressure phosphene tonometer display a higher mean and a larger standard deviation than those obtained with the Goldmann applanation tonometer (GAT). Differences between PPT and GAT readings tended to decrease as a function of increased Goldmann levels. The relation of Proview and Goldmann readings (r = 0.32) and the scatterplot were not consistent with the hypothesis that the 2 methods are equivalent. INTERPRETATION: Our results indicate that the pressure phosphene-type handheld tonometry method, which does not appear to provide an accurate and consistent measure of intraocular pressure, is substantially less reliable than the Goldmann method.

Resident glaucoma surgical training in United States residency programs.

PURPOSE: To determine current trends in resident glaucoma surgical training throughout the United States. METHODS: A comprehensive survey was sent to the residency director of all 121 ACGME-accredited ophthalmology training programs in the United States. RESULTS: The mean and median number of glaucoma procedures a resident will complete by the end of their training is 8.6 and 8 respectively for trabeculectomy, 5.3 and 4 for combined trabeculectomy/phacoemulsification, and 3.6 and 2 for tube-shunts. One percent of residents will gain experience as primary surgeon on trabeculectomies during their first year, 32% during their second year, and 67% during their third year. Seventy-five percent of residents are taught more than one trabeculectomy technique by more than one staff surgeon. Eighty-four percent of residents are taught glaucoma surgery almost exclusively by fellowship-trained glaucoma surgeons. Eighty-two percent of residents use antimetabolites (mitomycin C or 5-FU) as an adjunct to trabeculectomy most or all of the time. More than 96% of resident tube-shunt procedures use Ahmed, Baerveldt, or Molteno devices. Eighty percent of residents do not perform any pediatric glaucoma surgeries. Sixty-two percent of residents rotate out of their main facility to perform glaucoma surgery. CONCLUSIONS: Residents are being exposed to glaucoma surgery early in their residency training. Most are performing a variety of different procedures and techniques, and are taught by fellowship-trained surgeons. Residents gain very little exposure to pediatric glaucoma surgery. All programs reported compliance with minimum RRC requirements for glaucoma filtering surgery.

Sudden bilateral visual loss in a diabetic man.

This is a report of a case of the development of acute bilateral cataracts in a diabetic patient. A 28-year-old man presented to the emergency room with a 4-day history of acutely diminished vision. The patient had a recent history of hyperglycemia. On examination, vision was noted to be count-fingers bilaterally; both lenses were intumescent with dense cortical opacities. After 4 weeks, the cataracts had not resolved and cataract extraction surgery was performed, with improvement of the patient's vision. A review of the mechanism of this infrequent presentation of cataract is presented.

Comparison of the Icare rebound tonometry with the Goldmann applanation tonometry in a pediatric population.

We report the results of a comparative study at a single center on 214 eyes of 109 pediatric patients in whom IOP was measured using the Icare rebound tonometer and Goldmann applanation tonometry. Measurements from the two modalities demonstrated a correlation coefficient of 0.83 (P < 0.001), with Icare measuring on average 1.38 mm Hg higher. Compared to Goldmann, the Icare was more easily tolerated in the children studied. In 37 eyes that tolerated pachymetry, central corneal thickness was positively correlated with Icare measurements.

Resident cataract surgical training in United States residency programs.

A comprehensive survey was sent to the residency directors of 129 ophthalmology training programs in the United States. Forty percent of residents gained experience as primary surgeon during their first year; 43% performed only part of the surgery. Seventy-three percent began learning cataract extraction using the extracapsular cataract extraction (ECCE) technique, 24% began with phacoemulsification, and 2% began with either method. If beginning with ECCE, 18% must have completed more than 10 before moving to phacoemulsification, 37% more than 5, and 45% more than 1. Seventy-five percent learned various phacoemulsification techniques; 25% learned only 1 technique. If beginning with 1 technique, 44% began with the scleral tunnel combined with divide and conquer. Sixty-four percent learned phacoemulsification on the Alcon Legacy, 21% on the Alcon Legacy and Storz Millennium, and 6% on the Storz Millennium. Sixty-eight percent of residents rotated out of their main facility to perform cataract surgery. The mean and median number of cataract procedures a resident completed by the end of training was 113 and 100, respectively.

Surgical management of a dysfunctional filtering bleb.

This case report presents a patient who developed a large overhanging bleb following antimetabolite trabeculectomy surgery 6 years prior. Complaints included decreasing vision and foreign body sensation for several months. Successful excisional surgery with placement of compression sutures was performed. Visual acuity and intraocular pressure were maintained with the resolution of symptoms.

Implantation of second glaucoma drainage devices after failure of primary devices.

BACKGROUND AND OBJECTIVE: To evaluate the efficacy and safety of implantation of a second glaucoma drainage device for eyes that have failed a primary device. PATIENTS AND METHODS: Medical records of patients receiving a primary glaucoma drainage device at Bascom Palmer Eye Institute from January 1987 to October 1998 were reviewed, of which 18 eyes of 18 patients were studied. Patients failing a primary glaucoma drainage procedure and receiving a second glaucoma drainage device were included in this study. The second eye in the same patient was excluded if a second drainage implant was required. All patients received a second device in a standardized fashion with the drainage tube inserted in the anterior chamber. Main outcome measures included: visual acuity, intraocular pressure (IOP), antiglaucomatous medication, length of follow up, and surface area of glaucoma drainage device. Success was defined as an IOP less than or equal to 21 mm Hg with or without medications, and at least a 20% reduction in IOP, without the need for additional glaucoma procedures. RESULTS: The mean postoperative IOP (19.6 +/- 9.4 mm Hg; range, 8-50 mm Hg) was significantly (P = 0.006) lower than the mean preoperative IOP (29.5 +/- 8.1 mm Hg; range, 20-52 mm Hg) at last follow up (mean 19.6 +/- 13.6 months; range, 6-47 months). The mean number of postoperative antiglaucomatous medications (2.2 +/- 1.2; range 0-4) was statistically similar (P = 0.2) to mean preoperative number of antiglaucomatous medications (2.6 +/- 1.2, range 1-4). Using Kaplan-Meier estimates, successful IOP reduction was observed in 89%, 83%, 63%, and 37% of eyes at 6 months, 1, 2, and 3 years, respectively. Four patients (21%) had a decline in visual acuity. CONCLUSIONS: Implantation of secondary glaucoma drainage devices may be useful in eyes that have failed primary devices.

Effect of topical loteprednol on intraocular pressure after selective laser trabeculoplasty for open-angle glaucoma.

INTRODUCTION: To determine whether there is a statistically significant difference in the decrease in intraocular pressure (IOP) after selective laser trabeculoplasty (SLT) between patients receiving a 5-7 days co-administration of loteprednol versus no loteprednol over the course of 1 year. METHODS: We conducted a retrospective chart review to evaluate use of loteprednol in patients aged 30-85 years undergoing SLT for open-angle glaucoma at our center over a 3-year period. RESULTS: Three hundred and eighteen eyes from 313 patients who underwent a 360° SLT treatment between January 2008 and August 2011 were included in the analysis. Patients who received loteprednol showed a mean reduction of 2.5 (±SE 0.3) mmHg or 11.8% (±1.5%) in IOP versus a mean reduction of 3.2 (±0.6) mmHg or 14.9% (±2.5%) in those not treated with loteprednol. This difference showed a trend toward lower IOP without loteprednol, but this was not statistically significant (p = 0.29). CONCLUSION: Postoperative use of loteprednol does not appear to significantly affect IOP in patients undergoing SLT. A randomized double-blinded study in a larger group of patients would be required to clarify this issue. Until such information is available, we recommend that individual clinical judgment be used regarding whether to use topical steroids in patients undergoing SLT.

Comparing the efficacy of the monocular trial treatment paradigm with multiple measurements of intraocular pressure before and after treatment initiation in primary open-angle glaucoma.

The monocular trial has been proposed as a test to help control for diurnal fluctuations in eye pressure when assessing medication effectiveness. We undertook a prospective study to determine the sensitivity and specificity of the monocular trial as a test for determining the effectiveness of a glaucoma medication. The efficacy of the monocular trial was compared to the diagnostic paradigm of repeated pre- and post-treatment measurements in determining whether an intraocular pressure (IOP)-lowering drug is effective. Forty-two patients with newly diagnosed open-angle glaucoma completed five visits: visit 1 for determining eligibility, obtaining consent, and measuring IOP, visit 2 for a second pressure measurement, and visit 3 for a third pressure reading. The new medication was then started in one eye. IOP measurements were made at weeks 4 and 6. The gold standard IOP change was defined as the difference in mean between the pre- and post-medication visits. A medication was deemed effective if this difference was at least 15%. The monocular trial pressure change was defined as the IOP change in the treated eye between the visit immediately before and immediately after the medication addition, corrected by subtracting the pressure change in the untreated eye. All 42 patients completed the full protocol with good compliance. Twenty-five of 42 (60%) medication additions were considered effective by the gold standard method, and 25/42 (60%) by the monocular trial method. However, the two methods agreed in only 26 patients (17 Yes/Yes, 9 No/No). The calculated sensitivity was low (0.68), with a specificity of 0.53. The monocular trial can give useful clues as to whether a medication is effective, but should not be the only information used in making this determination. To obtain the most valid results, multiple pressure checks should be done before and after starting a new medication.

Evaluation of tensile strength of tissue adhesives and sutures for clear corneal incisions using porcine and bovine eyes, with a novel standardized testing platform.

BACKGROUND: Tissue adhesives for ophthalmologic applications were proposed almost 50 years ago, yet to date no adequate tissue glues have been identified that combine strong sealing properties with adequate safety and absence of postsurgical side effects. In recent years, cataract surgeries and Descemet's stripping with endothelial keratoplasty procedures have significantly increased the number of clear corneal incisions performed. One of the obstacles to discovery and development of novel tissue adhesives has been the result of nonstandardized testing of potential tissue glues. METHODS: We developed an instrument capable of controlling intraocular pressure in explanted porcine and bovine eyes in order to evaluate sealants, adhesives, and surgical closure methods used in ophthalmic surgery in a controlled, repeatable, and validated fashion. We herein developed and validated our instrument by testing the adhesive properties of cyanoacrylate glue in both porcine and bovine explant eyes. RESULTS: The instrument applied and maintained intraocular pressure through a broad range of physiological intraocular pressures. Cyanoacrylate-based glues showed significantly enhanced sealing properties of clear corneal incisions compared with sutured wounds. CONCLUSION: This study shows the feasibility of our instrument for reliable and standardized testing of tissue adhesive for ophthalmological surgery.

Resident laser in situ keratomileusis surgical training in United States residency programs.

To determine current trends in resident laser in situ keratomileusis (LASIK) training in the United States, a comprehensive survey was sent to the residency coordinator, chairman, or refractive surgery director of all 113 ophthalmology training programs in the U.S. accredited by the Accreditation Council for Graduate Medical Education. The response rate was 64%. Of the respondents, 54% were from programs in which residents performed LASIK surgery, typically as third-year residents; residents in these programs performed a mean of 4 LASIK surgeries (range 1 to 10 surgeries) during residency. The Visx Star was the most commonly used excimer laser platform and the Hansatome the most commonly used microkeratome. Most programs had 1 attending physician teaching the residents refractive surgery, which was typically performed at the main residency facility. Most programs had significant discounted pricing (>50%) for resident-performed LASIK.

Interaction of ocular hypotensive agents (PGF2 alpha analogs-bimatoprost, latanoprost, and travoprost) with MDR efflux pumps on the rabbit cornea.

PURPOSE: The objectives of this work were (i) to screen ocular hypotensive prostaglandin (PGF2 alpha) analogs--bimatoprost, latanoprost, and travoprost as well as their free acid forms--for interaction with efflux pumps on the cornea and (ii) to assess the modulation of efflux upon co-administration of these prostaglandin analogs. METHODS: Cultured rabbit primary corneal epithelial cells (rPCEC) were employed as an in vitro model for rabbit cornea. Transporter-specific interaction studies were carried out using Madin-Darby canine kidney (MDCK) cells overexpressing MDR1, MRP1, MRP2, MRP5, and BCRP. Freshly excised rabbit cornea was used as an ex vivo model to determine transcorneal permeability. RESULTS: Cellular accumulation studies clearly showed that all prostaglandin analogs and their free acid forms are substrates of MRP1, MRP2, and MRP5. Bimatoprost was the only prostaglandin analog in this study to interact with P-gp. In addition, none of these molecules showed any affinity for BCRP. K (i) values of these prostaglandin analogs obtained from dose-dependent inhibition of erythromycin efflux in rPCEC showed bimatoprost (82.54 microM) and travoprost (94.77 microM) to have similar but higher affinity to efflux pumps than latanoprost (163.20 microM). Ex vivo studies showed that the permeation of these molecules across cornea was significantly elevated in the presence of specific efflux modulators. Finally, both in vitro and ex vivo experiments demonstrated that the efflux of these prostaglandin analogs could be modulated by co-administering them together. CONCLUSION: Bimatoprost, latanoprost, travoprost, and their free acid forms are substrates of multiple drug efflux pumps on the cornea. Co-administration of these molecules together is a viable strategy to overcome efflux, which could simultaneously elicit a synergistic pharmacological effect, since these molecules have been shown to activate different receptor population for the reduction of intraocular pressure (IOP).