Equine ulcerative keratitis with furrow: A review of the outcomes of 72 cases from 1987 to 2015.

BACKGROUND: Ulcerative keratitis with peripheral furrow formation is a poorly-described condition which has been associated with a grave prognosis due to rapid necrosis of the cornea. OBJECTIVE: To describe the infectious aetiologies associated with furrow-forming ulcerative keratitis, its overall clinical course and the efficacy of medical and surgical intervention in horses. STUDY DESIGN: Retrospective clinical case series. METHODS: Medical records of 72 horses which presented with furrow-forming ulcerative keratitis at the University of Florida between 1987 and 2015 were reviewed. RESULTS: Seventy-two horses (72 eyes) with furrow-forming ulcerative keratitis were treated at the University of Florida between 1987 and 2015. Of these, a definitive aetiologic diagnosis was available for 37 eyes. Ten of 37 eyes (27%) were diagnosed with fungal keratitis based on cytology of corneal scraping, culture, histopathology and/or fungal PCR. Fourteen of 37 eyes (38%) were diagnosed with a mixed fungal and bacterial keratitis. Thirteen of 37 eyes (35%) were diagnosed with bacterial keratitis. Overall, 26 of 72 total eyes were treated with medical therapy alone (36%). Forty-six of 72 eyes were treated medically and surgically (64%). Of the 26 eyes which received medical therapy, 20 healed with a positive visual outcome (77%) and 6 eyes were non-visual (23%). Of the 46 eyes which received surgical intervention, 40 healed with a positive visual outcome (87%), while six eyes were non-visual (13%). Altogether, 60 of 72 eyes healed with a positive visual outcome following medical or surgical treatment of furrow-forming ulcerative keratitis (83%). Twelve of 72 eyes failed treatment (17%), with six eyes requiring enucleation and six globes becoming phthisical after treatment. MAIN LIMITATIONS: Inconsistencies in available medical record data due to the large span of time (1987-2015) are inherent in this retrospective study, along with gradual evolution of corneal surgical techniques and medical therapies over the decades. CONCLUSIONS: Furrow-forming ulcerative keratitis was associated with a positive visual outcome in 83% of horses treated at the University of Florida between the years 1987 and 2015. Furrow formation may be associated with either fungal or bacterial infection.

Progesterone binding nano-carriers based on hydrophobically modified hyperbranched polyglycerols.

Progesterone (Pro) is a potent neurosteroid and promotes recovery from moderate Traumatic Brain Injury but its clinical application is severely impeded by its poor water solubility. Here we demonstrate that reversibly binding Pro within hydrophobically modified hyperbranched polyglycerol (HPG-Cn-MPEG) enhances its solubility, stability and bioavailability. Synthesis, characterization and Pro loading into HPG-Cn-MPEG is described. The release kinetics are correlated with structural properties and the results of Differential Scanning Calorimetry studies of a family of HPG-Cn-MPEGs of varying molecular weight and alkylation. While the maximum amount of Pro bound correlates well with the amount of alkyl carbon per molecule contributing to its hydrophobicity, the dominant first order rate constant for Pro release correlates strongly with the amount of structured or bound water in the dendritic domain of the polymer. The results provide evidence to justify more detailed studies of interactions with biological systems, both single cells and in animal models.

Effect of frailty on short- and mid-term outcomes in vascular surgical patients.

BACKGROUND: Frailty is a multidimensional vulnerability resulting from age-associated decline. The impact of frailty on outcomes was assessed in a cohort of vascular surgical patients. METHODS: The study included patients aged over 65 years with length of hospital stay (LOS) greater than 2 days, who were admitted to a tertiary vascular unit over a single calendar year. Demographics, mode of admission, diagnosis, mortality, LOS and discharge destination were recorded, as well as a variety of frailty-specific characteristics. The impact of frailty on LOS, discharge destination, survival and readmission rate was assessed using multivariable regression techniques. The ability of the models to predict these outcomes was also assessed. RESULTS: In total, 413 patients of median age 77 years were followed for a median of 18 (range 12-24) months. The in-hospital, 3- and 12-month mortality rates were 3·6, 8·5 and 13·8 per cent respectively. Receiver operating characteristic (ROC) curve analysis revealed that frailty-based regression models were excellent predictors of 12-month mortality (area under the ROC curve (AUC) = 0·81), prolonged LOS (AUC = 0·79) and discharge to a care institution (AUC = 0·84). A simple additive frailty score using six key features retained strong predictive power for 12-month mortality (AUC = 0·83), discharge to a care institution (AUC = 0·78) and prolonged LOS (AUC = 0·74). This frailty score was also strongly associated with readmission rates (P < 0·001). CONCLUSION: Frailty in vascular surgery patients predicts a multiplicity of poorer outcomes. Optimal management should include identification of at-risk patients and treatment of modifiable risk factors.

Microbiological profile of donor corneas stored for tectonic transplantation purposes in rabbits / Microbiologia de amostras de bancos de córneas destinadas a transplantes, em coelhos

This study aimed to evaluate the microbiota of donor rabbit corneas stored for tectonic transplantation purposes. Swabs from both corneas of 20 rabbits were carefully collected and submitted to microorganism isolation and identification. After this first swab collection, rabbits were euthanized for reasons other than this project and the eyes were enucleated. The corneas were collected and stored to compose the cornea tissue bank. Corneas were stored in a 0.3% tobramycin solution at -20ºC. After 30 days, the corneas were thawed at room temperature and removed from the antibiotic. New swabs were obtained from the corneas and submitted to microorganism isolation and identification. Gram positive organisms were predominant in the rabbit corneal flora before storage and the Staphylococcus sp. was the most common microorganism isolated from those samples. No growth was observed on the samples collected after storage. The methods used for collection and storage of the corneas were efficient to constitute a sterile donor corneal tissue bank.

Analisaram-se córneas armazenadas para transplantes tectônicos usando-se suabes coletados de 20 coelhos, visando ao isolamento e à identificação de microrganismos. Após a coleta das amostras, os coelhos foram submetidos à eutanásia, por razões alheias ao estudo, e enucleados. As córneas foram coletadas e armazenadas a fim de se constituir o banco de córneas. O armazenamento deu-se em solução de tobramicina 0,3% a -20ºC, por 30 dias. Após esse período, as córneas foram descongeladas à temperatura ambiente e removidas da solução de antibiótico. Novos suabes foram coletados e submetidos ao isolamento e à identificação dos microrganismos. A flora corneal mostrou-se predominantemente composta por bactérias Gram positivas, sendo o Staphylococcus sp. o mais identificado. Não se verificou crescimento de colônias bacterianas ou fúngicas nas amostras após o armazenamento. Considerando-se a maneira como a pesquisa foi concebida e as injunções do meio em que ela foi realizada, há como admitir, pela ausência de crescimento microbiano nas amostras armazenadas, que a técnica de armazenamento empregada é segura para a estocagem de córneas destinadas a transplantes.

Visual outcome after corneal transplantation for corneal perforation and iris prolapse in 37 horses: 1998-2010.

REASONS FOR PERFORMING STUDY: We wanted to investigate the visual outcome of horses presented with iris prolapse and treated with corneal transplantation. OBJECTIVE: To evaluate the visual outcome of horses with iris prolapse treated with penetrating keratoplasty alone and penetrating keratoplasty in combination with overlying conjunctival or amniotic membrane grafting. METHODS: A retrospective medical records study of horses presented to the University of Florida Veterinary Medical Center for iris prolapse and treated with penetrating keratoplasty in the period of 1998-2010. Data collected from the medical records included signalment, clinical descriptions of ocular lesions, treatments, and therapeutic outcome. RESULTS: Iris prolapses in this study were caused by corneal ulcers with keratomalacia (n = 37). All horses were treated medically for infection, hyperproteinase activity and iridocyclitis, and then surgically treated with either penetrating keratoplasty alone (n = 9) or penetrating keratoplasty with either a conjunctival pedicle flap (n = 22), amniotic membrane transplant (n = 5) or amnion membrane and conjunctival pedicle flap (n = 1). The eyes were visual postoperatively in a majority of the cases (n = 24; 64.9%). Limited vision was noted in 6 eyes (16.2%), 3 eyes became phthisical (8.1%) and 4 globes were enucleated (10.8%). Graft rejection manifested as some degree of donor corneal graft opacification in all cases. Anterior synechiae were present in 48.6% of the eyes. Wound dehiscence and aqueous humour leakage were also common as post operative problems. CONCLUSION: Penetrating keratoplasty alone or in combination with an overlying graft of conjunctiva or amniotic membrane can achieve a successful visual outcome in a high percentage of horses with iris prolapse.

Development and in vitro characterization of paclitaxel and docetaxel loaded into hydrophobically derivatized hyperbranched polyglycerols.

In this study we report the development and in vitro characterization of paclitaxel (PTX) and docetaxel (DTX) loaded into hydrophobically derivatized hyperbranched polyglycerols (HPGs). Several HPGs derivatized with hydrophobic groups (C(8/10) alkyl chains) (HPG-C(8/10)-OH) and/or methoxy polyethylene glycol (MePEG) chains (HPG-C(8/10)-MePEG) were synthesized. PTX or DTX were loaded into these polymers by a solvent evaporation method and the resulting nanoparticle formulations were characterized in terms of size, drug loading, stability, release profiles, cytotoxicity, and cellular uptake. PTX and DTX were found to be chemically unstable in unpurified HPGs and large fractions (∼80%) of the drugs were degraded during the preparation of the formulations. However, both PTX and DTX were found to be chemically stable in purified HPGs. HPGs possessed hydrodynamic radii of less than 10nm and incorporation of PTX or DTX did not affect their size. The release profiles for both PTX and DTX from HPG-C(8/10)-MePEG nanoparticles were characterized by a continuous controlled release with little or no burst phase of release. In vitro cytotoxicity evaluations of PTX and DTX formulations demonstrated a concentration-dependent inhibition of proliferation in KU7 cell line. Cellular uptake studies of rhodamine-labeled HPG (HPG-C(8/10)-MePEG(13)-TMRCA) showed that these nanoparticles were rapidly taken up into cells, and reside in the cytoplasm without entering the nuclear compartment and were highly biocompatible with the KU7 cells.

Targeted lamellar keratoplasty in the horse: a paradigm shift in equine corneal transplantation.

Many equine keratopathies primarily affect individual layers of the cornea. Targeted lamellar keratoplasty rather than full thickness penetrating keratoplasty (PK) seems most appropriate to the microsurgical management of many of these equine keratopathies. Despite the positive results with PK in the horse the author now suggests that this procedure should be rarely utilised in the treatment of equine keratitis. Selective lamellar surgical replacement of only the diseased corneal layers while retaining unaffected normal corneal layers represents a new paradigm shift in the field of corneal transplantation in the horse.

International Equine Ophthalmology Consortium (IEOC) Symposium.

This first IEOC symposium met its goals of gathering a group of leading equine ophthalmology clinicians and researchers to identify the challenges of the field. To facilitate collaboration, notes from round-table discussions, including the ideas and plans that were discussed are being complied and will be distributed to the attendees. Development of an IEOC membership organisation and website was discussed and supported by the group in an effort further to advance the science of equine ophthalmology. To present results from the collaborations made at this first IEOC meeting, an IEOC mini-symposium will be held at the American College of Veterinary Ophthalmologists Annual Meeting in Chicago Illinois, on 6th November 2009. The second annual IEOC symposium will be held in Vienna, Austria on 4th and 5th June 2010.

Deep lamellar endothelial keratoplasty in 10 horses.

OBJECTIVE: To describe and evaluate a surgical technique utilized for the therapy of deep corneal stromal abscesses (DSA) in horses. The DSA is excised and replaced with a partial thickness corneal lamellar allograft. METHODS: A retrospective clinical study describing the indications for the surgical technique utilized and the outcomes of this procedure in 10 eyes of 10 horses. RESULTS: Each affected eye had a discrete DSA within the posterior stroma. An initial partial thickness semicircular corneal incision was made at the limbus, followed by anterior stromal lamellar dissection over the lesion. After excision of the DSA and replacement with a larger diameter split-thickness donor button, the anterior stroma was replaced into its original position and the initial corneal incision was repaired. All of the animals that underwent deep lamellar endothelial keratoplasty (DLEK) procedure healed appropriately and with subjectively less postoperative scarring and complications than previously described surgical approaches to DSA. CONCLUSIONS: This procedure is an effective technique for surgical removal of DSA in horses and, in most cases, results in a visual and cosmetically acceptable globe. The advantages of this technique compared to other surgical approaches to DSA are the peripheral location of the incision, shortened anesthesia times, the resultant minimal scarring and shorter healing times associated with DLEK.

Intranictitans tacking for replacement of prolapsed gland of the third eyelid in dogs.

OBJECTIVE: To evaluate a new procedure for fixation of prolapsed nictitans glands to the cartilage of the nictitans that will not interfere with the mobility of the nictitating membrane. METHODS: A prospective clinical trial utilizing a nonabsorbable suture to anchor the prolapsed gland to the cartilage of the third eyelid was undertaken. Fifteen eyes of 10 dogs were included in the study. A 4-0 nylon suture was passed from the anterior surface of the third eyelid through the base of the cartilage to the posterior aspect and then tunneled circumferentially beneath the conjunctiva over and around the prolapsed gland. The suture was then passed through the cartilage again to the anterior face of the third eyelid. The gland was replaced into its normal position as the suture was slowly tightened and then tied on the anterior aspect of the nictitans. RESULTS: Over a period of several weeks, the glands reduced in size and took on a normal appearance. All glands but one remained in place for the length of follow-up, which ranged from 2 weeks to 33 months. CONCLUSIONS: This procedure results in acceptable cosmetic effects with the return of the gland to its normal position posterior to the nictitating membrane. The advantage of this technique over traditional tacking to the orbital rim is that the third eyelid retains its normal mobility and, thus, its protective functions. The procedure once mastered is very quick and can be performed in less time than many of the traditional replacement techniques.

Conjugation to hyperbranched polyglycerols improves RGD-mediated inhibition of platelet function in vitro.

RGD (arginine-glycine-aspartic acid) is a known peptide sequence that binds platelet integrin GPIIbIIIa and disrupts platelet-fibrinogen binding and platelet cross-linking during thrombosis. RGD peptides are unsuitable for clinical applications due to their high 50% inhibitory concentration (IC50) and low in vivo residence times. We addressed these issues by conjugating RGD peptides to biocompatible macromolecular carriers: hyperbranched polyglycerols (HPG) via divinyl sulfone. The GPIIbIIIa binding activity of RGD was maintained after conjugation and the effectiveness of the HPG-RGD conjugate was dependent upon molecular weight and the number of RGD peptides attached to each HPG molecule. These polyvalent inhibitors of platelet aggregation decreased the IC50 of RGD in an inverse linear manner based on the number of RGD peptides per HPG. Since HPG-RGD conjugates do not cause platelet activation by degranulation and certain substitution ratios do not increase fibrinogen binding to resting platelets, HPG-RGD may serve as a model for a novel class of antithrombotics.

Corneal transplantation for inflammatory keratopathies in the horse: visual outcome in 206 cases (1993-2007).

OBJECTIVE: To evaluate the visual outcome of three techniques of corneal transplantation surgery in treating severe inflammatory keratopathies in the horse. DESIGN: Retrospective medical records study. ANIMALS STUDIED: Medical records of 206 horses that received corneal transplantation surgery at the University of Florida Veterinary Medical Center from 1993 to 2007 were reviewed. PROCEDURE: Data collected from the medical records included signalment, types of ocular lesions, type of transplant surgery performed, length of follow-up, complications, and visual outcomes. RESULTS: Full thickness penetrating keratoplasty (PK) was performed in 86 horses for melting ulcers, iris prolapse/descemetoceles, and medically nonresponsive full thickness stromal abscesses (SA). Posterior lamellar keratoplasty (PLK) and deep lamellar endothelial keratoplasty (DLEK) are split thickness penetrating keratoplasties that were utilized for medically nonresponsive deep stromal abscesses (DSA) in 54 and 66 eyes, respectively. The most common postoperative surgical complication was graft rejection and varying degrees of graft opacification. Wound dehiscence and aqueous humor leakage was also a common postoperative problem. A positive visual outcome was achieved for PK, PLK, and DLEK in 77.9%, 98.1%, and 89.4%, respectively. CONCLUSIONS: Corneal transplantation is a tectonically viable surgery in the horse with an overall success rate of 88.5% in maintaining vision when treating vascularized and infected corneal disease in the horse.

Lithium toxicity from an Internet dietary supplement.

INTRODUCTION: The widespread availability of medications and herbal products on the Internet has increased the potential for poisonings. We are reporting a case of mild, acute lithium toxicity occurring after the intentional misuse of a lithium-containing "dietary supplement" (Find Serenity Now) obtained over the Internet. CASE REPORT: An 18-year-old woman presented to our emergency department (ED) after ingesting 18 tablets of Find Serenity Now; each tablet contained, according to the listing, 120 mg of lithium orotate [3.83 mg of elemental lithium per 100 mg of (organic) lithium orotate compared to 18.8 mg of elemental lithium per 100 mg of (inorganic) lithium carbonate]. The patient complained of nausea and reported one episode of emesis. Her examination revealed normal vital signs. The only finding was a mild tremor without rigidity. Almost 90 minutes after the ingestion, her serum lithium level was 0.31 mEq/L, a urine drug screen was negative, and an electrocardiogram (ECG) showed a normal sinus rhythm. The patient received intravenous fluids and an anti-emetic; one hour later, her repeat serum lithium level was 0.40 mEq/L. After 3 hours of observation, nausea and tremor were resolved, and she was subsequently transferred to a psychiatric hospital for further care. Prior human and animal data have shown similar pharmacokinetics and shared clinical effects of these lithium salts. DISCUSSION: Over-the-Internet dietary supplements may contain ingredients capable of causing toxicity in overdose. Chronic lithium toxicity from ingestion of this product is also of theoretical concern.

Proteinases of the cornea and preocular tear film.

Maintenance and repair of corneal stromal extracellular matrix (ECM) requires a tightly coordinated balance of ECM synthesis, degradation and remodeling in which proteolytic enzymes (proteinases) perform important functions. There are natural proteinase inhibitors present in preocular tear film (PTF) and cornea simultaneously with proteinases that prevent excessive degradation of normal healthy tissue. Disorders occur when there is an imbalance between proteinases and proteinase inhibitors in favor of the proteinases, causing pathologic degradation of stromal collagen and proteoglycans in the cornea. Two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, are of major importance in terms of remodeling and degradation of the corneal stromal collagen. Immunohistochemical studies have shown different origins of MMP-2 and -9. MMP-2 is synthesized by corneal keratocytes and performs a surveillance function in the normal cornea, becoming locally activated to degrade collagen molecules that occasionally become damaged. Alternatively, MMP-9 may be produced by epithelial cells and polymorphonuclear neutrophils following corneal wounding. Because the cornea is in close contact with the preocular tear film (PTF), proteinases have been evaluated in the PTF. In damaged corneas, total proteolytic activity in the tear fluid was found to be significantly increased compared to normal eyes and contralateral eyes. Studies analyzing the proteolytic activity in serial PTF samples during corneal healing led to the following conclusions: ulcerative keratitis in animals is associated with initially high levels of tear film proteolytic activity, which decrease as ulcers heal; proteinase levels in melting ulcers remain elevated leading to rapid progression of the ulcers. The success of medical and surgical treatment of the corneal ulcers is reflected by the proteolytic activity in tears. In animals, successful treatment leads to a rapid reduction in tear film proteolytic activity that corresponds with the improvement in the clinical signs of corneal ulceration. The in vitro effects of various compounds on proteolytic activity in the tear fluid of animals with ulcerative keratitis have been evaluated and their important inhibitory effects have been confirmed. Because these various compounds utilize different mechanisms to inhibit various families of proteinases, a combination of these proteinase inhibitors may be beneficial.

Combined keratectomy, strontium-90 irradiation and permanent bulbar conjunctival grafts for corneolimbal squamous cell carcinomas in horses (1990-2002): 38 horses.

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of postoperative beta-irradiation with strontium-90 as an adjunctive treatment to superficial keratectomy and permanent bulbar conjunctival graft for removal of equine corneolimbal squamous cell carcinoma (SCC), in decreasing recurrence rate. STUDY: The retrospective case study included 38 horses diagnosed and treated for SCC of the eye that involved the limbus and/or cornea. The patients were treated between 1990 and 2002, with strontium-90 irradiation immediately after corneal and conjunctival graft surgery. Recurrence was defined as the postoperative and postirradiation regrowth of SCC in the same site and globe that was previously treated. RESULTS: The Appaloosa was the most commonly represented breed and horses that had more than one base coat color represented the majority of the cases (53%). The coat colors of white, chestnut/sorrel and gray were the most commonly represented colors of the horses treated. Eight horses (21%) could not be assessed for tumor recurrence due to lack of two or more post-treatment examinations, and another horse was enucleated 6 days postoperatively due to progressive corneal ulceration. Twenty-four horses (63% of the entire study population; 83% of the followed cases) had a mean +/- SD of 1754 +/- 1319 days without tumor recurrence, ranging from 14 days to 5110 days. Five horses (13% of the entire study population; 17% of the assessed horses) had tumor recurrence at a mean +/- SD of 449 +/- 339 days with a range of 29 days to 900 days. For the five recurrences, treatment included local excision (n = 1), enucleation (n = 2), and additional strontium-90 therapy (n = 3). CONCLUSIONS: The combination of superficial keratectomy, beta-irradiation and permanent bulbar conjunctival grafts for limbal, corneal or corneolimbal SCC in horses is effective in at least 83% of the horses. Recurrence occurred in about 17% of the horses. Multiple biannual re-examinations are recommended to observe for tumor recurrence.

Amniotic membrane transplantation for corneal surface reconstruction after excision of corneolimbal squamous cell carcinomas in nine horses.

OBJECTIVE: The purpose of this study was to evaluate the usefulness and effectiveness of permanent amniotic membrane transplantation as an adjunctive treatment to superficial keratectomy alone or combined with strontium-90 irradiation for treatment of equine corneolimbal squamous cell carcinoma (SCC) to decrease corneal scarring and recurrence rate. STUDY: The retrospective case study included 11 horses (n = 12 eyes) diagnosed and treated for ocular SCC that involved the limbus and cornea. Nine of those horses (n = 9 eyes) were treated between 2002 and 2006, with superficial lamellar keratectomy alone or combined with strontium-90 irradiation and followed by placement of a permanent amniotic membrane graft in the surgical defect. The level of scarring (i.e. the clarity of the cornea) resulting with the use of amniotic membrane was subjectively compared to cases where a permanent bulbar conjunctival graft was performed following keratectomy combined with strontium-90 irradiation or cryotherapy (n = 3 eyes). Recurrence was defined as the postoperative and postirradiation regrowth of SCC in the same site and globe. RESULTS: The nine horses that received an amniotic membrane graft after keratectomy alone or combined with irradiation showed a minimal level of scarring in a cornea that regained a greater transparency in comparison to the horses that were treated with a bulbar conjunctival graft. All of the horses that received an amniotic membrane graft had 226 +/- 218 days of follow-up without tumor recurrence (mean +/- SD), ranging from 21 days to 778 days. CONCLUSIONS: The combination of superficial keratectomy alone or associated with beta-irradiation and permanent amniotic membrane transplantation is an effective treatment of corneal or corneolimbal SCC in horses. The placement of an amniotic membrane material represents an alternative surgical procedure to bulbar conjunctival grafts, especially if there is a lack of bulbar conjunctiva tissue available after tumor resection or if a particularly large corneal resection is necessary. The amniotic membrane is incorporated into the corneal defect and seems to create noticeably much less scarring than a corneal defect covered by bulbar conjunctiva.

Effectiveness of commercially-available antibiotic-impregnated implants.

The aim of this study was to determine the effectiveness of antibiotic-impregnated implants in the prevention of bone infection. We used a model of contaminated fracture in goats to evaluate four treatment groups: no treatment, hand-made tobramycin-impregnated polymethylmethacrylate beads, commercially-available tobramycin-impregnated calcium sulphate pellets and commercially-available tobramycin-impregnated polymethylmethacrylate beads. Three weeks after intraosseous inoculation with streptomycin-resistant Staphylococcus aureus tissue cultures showed no evidence of infection in any of the antibiotic-treated groups. All of the cultures were positive in the untreated group. These results show that effective local antibiotic delivery can be obtained with both commercially-available products and with hand-made polymethylmethacrylate beads. The calcium sulphate pellets have the advantage of being bioabsorbable, thereby obviating the need for a second procedure to remove them.

Pars plana vitrectomy for the treatment of ophthalmomyiasis interna posterior in a dog.

Unilateral chorioretinitis caused by ophthalmomyiasis interna posterior in a 5-month-old, female spayed Dachshund is reported. Larva removal by pars plana vitrectomy was performed after an unsuccessful photocoagulation of the organism. The larva was intact after surgical removal and was identified as a first stage instar Cuterebra spp. larva. The eye remains visual and comfortable with no signs of residual or recurrent inflammation postoperatively. This report describes, for the first time, the successful surgical retrieval of an intravitreal fly larva in a dog using vitrectomy techniques without sacrificing either the globe or vision, and taxonomic identification of the parasite.

Optic nerve head neuroretinal rim blood flow differences in monkeys with laser-induced glaucoma.

INTRODUCTION: The blood flow of the neuroretinal rim (NRR) of the optic nerve head (ONH) of the rhesus monkey with laser-induced glaucoma was examined. METHODS: Argon laser photocoagulation of the trabecular meshwork to induce elevated intraocular pressure (IOP) was performed in one eye of nine normal male rhesus monkeys. The nasal and temporal NRR of the monkey ONH were examined by the Heidelberg retina tomograph/flowmeter (HRT/HRF) under neuromuscular blockade. A mixed effect analysis of variance was used to determine significant differences between eyes and between locations in the eyes. RESULTS: The average IOP in the hypertensive glaucoma and normal eyes was 34.8 +/- 7.2 and 16.0 +/- 1.9 mmHg, respectively. The HRT determined average overall cup to disc (C/D) area ratio in the glaucoma and normal eyes, which was 0.49 +/- 0.28 and 0.22 +/- 0.16, respectively. The mean temporal NRR HRF flow in the hypertensive eyes was significantly greater than in the normotensive eyes (P < 0.0001), than in the nasal NRR of the hypertensive eyes (P < 0.0001) and than in the nasal NRR of the normotensive eyes (P < 0.01). The mean nasal NRR HRF flow in the hypertensive eyes was significantly less than in the nasal NRR of the normotensive eyes (P < 0.01). There was no statistical difference between the mean HRF flow of the temporal and nasal NRR of the normotensive eyes. The elevated IOP positively influenced the flow values in the hypertensive eye (r = 0.724). CONCLUSIONS: The capillary microcirculation of the temporal NRR of the rhesus monkey ONH with laser-induced glaucoma has significantly increased blood flow, and the nasal NRR significantly reduced blood flow compared to blood flow in the NRR of normal normotensive monkey eyes.

Profiles of matrix metalloproteinase activity in equine tear fluid during corneal healing in 10 horses with ulcerative keratitis.

OBJECTIVE: Levels of tear film matrix metalloproteinases (MMPs) activity are significantly elevated in horses with ulcerative keratitis and contribute to the excessive breakdown of stromal collagen. Changes in the amount of proteolytic activity in horse tear film during corneal healing and stromal remodeling have not yet been reported, but we hypothesize they should decrease. In the present study we analyzed serial tear fluid from horses with ulcerative keratitis to identify any changes in MMP activity during corneal healing and stromal remodeling. PROCEDURES: Samples of tear fluid were obtained from both eyes of 10 horses with ulcerative keratitis on the day of admission (day 1) at the hospital and then at various time points until complete healing of the cornea. Tear film MMP2 and MMP9 activity was determined by quantitative gelatin zymography. In all cases medical treatment included topical applications of equine serum, antibiotics, atropine and systemic administration of anti-inflammatory drugs. Surgical procedures were performed in several cases on day 2 in addition to the medical treatment. RESULTS: The mean total MMP activity (+/- SD) measured in relative standard units (RSU) in the tear fluid of the ulcerated eye (2.44 +/- 1.44) of the 10 horses was significantly higher than the mean in the contralateral eye (0.81 +/- 0.68) (P = 0.006), on the day of admission at the VMTH. The mean MMP activity in these ulcerated eyes significantly decreased (-82.4%) between the first day of admission and the day when the ulcer had completely healed (P = 0.0002). The activity level in the healed eye (0.43 +/- 0.17) was not significantly different to the one in the contralateral eye (0.36 +/- 0.18) on the day of complete corneal healing (P = 0.374). The level of MMP activity in the contralateral eye also decreased from 0.81 +/- 0.68-0.36 +/- 0.18 but this decrease (56%) was not significant (P = 0.069). CONCLUSIONS: Ulcerative keratitis in horses is associated with initially high levels of tear film proteolytic activity that decrease as the ulcers heal. The success of medical and surgical treatment of the corneal ulcers is reflected by the enzyme activity in tears. In horses successful treatment does lead to a rapid reduction in tear film proteolytic activity that corresponded with the improvement in the clinical signs of corneal ulceration. Measurement of MMP activity in the tear film might represent a way to monitor the progression of corneal healing in horses with ulcerative keratitis.