793 research outputs found
Diagnosis and Treatment of Ocular Proptosis
No full textProptosis, or traumatic forward displacement of the globe out of the orbit, is a serious ocular emergency that requires immediate attention to minimize discomfort and damage to the eye (Figure 1). With proptosis, the eyelid margins are trapped behind the equator of the globe and, together with profound tissue swelling in the orbit, prevent the eyeball from returning to a normal position.This article is published as Foote, Braidee C. and Lionel Sebbag. "Diagnosis and Treatment of Ocular Proptosis." Today’s Veterinary Practice, January/February 2020. Posted with permission.</p
Case Report: Clinical Remission in a Cat With Severe Bilateral Eosinophilic Keratitis Receiving Combined Immunosuppressive Therapy (Triamcinolone Acetonide and Tacrolimus)
No full textA 2-year-old domestic shorthair cat was examined for severe keratitis of 10 months duration, non-responsive to 0.1% dexamethasone q8-12h. Patient and owner compliance were poor given ocular discomfort and hiding behavior. On presentation, both eyes (OU) had severe ulcerative keratitis that masked examination of deeper structures and resulted in absent menace response OU. Corneal cytology was consistent with eosinophilic keratitis (EK) OU. Initial therapy included subcutaneous triamcinolone acetonide injection (0.2 mg/kg), 0.3% ciprofloxacin OU q12h, and two compounded drugs started 5 days later upon receipt: 0.5% tacrolimus OU q6h, 0.5% cidofovir OU q12h. Visual behavior and ocular comfort were reportedly much improved within 24 h. At the first recheck (Day 11), patient and owner compliance were reported to be excellent, menace response was positive OU, and keratitis was dramatically reduced OU with absent fluorescein uptake. Subcutaneous triamcinolone acetonide was repeated (0.2 mg/kg), ciprofloxacin was discontinued, cidofovir was continued q12h, and tacrolimus was slowly tapered (q8h × 3 weeks then q12h). Keratitis was nearly 100% resolved at the second recheck (Day 38); cidofovir was discontinued and tacrolimus was slowly tapered (q12h × 1 week, q24h × 4 weeks, q48h × 4 weeks) then discontinued. A third recheck (Day 101) confirmed clinical remission OU, and disease did not reoccur within a 1 year follow up period (photographic documentation by owner). In sum, adjunct use of triamcinolone acetonide greatly improved therapeutic compliance and helped control severe EK in a rapid and effective manner.This article is published as Romaneck, Amanda K., and Lionel Sebbag. "Case report: clinical remission in a cat with severe bilateral eosinophilic keratitis receiving combined immunosuppressive therapy (triamcinolone acetonide and tacrolimus)." Frontiers in Veterinary Science 8 (2021): 580396.
DOI: 10.3389/fvets.2021.580396.
Copyright 2021 Romaneck and Sebbag.
Attribution 4.0 International (CC BY 4.0).
Posted with permission
Pharmacokinetics of Oral Prednisone at Various Doses in Dogs: Preliminary Findings Using a Naïve Pooled-Data Approach
No full textThis pilot study aimed to determine the plasma pharmacokinetics of prednisone and its active metabolite prednisolone following oral prednisone administration in dogs—using dosing regimens that cover anti-inflammatory to immuno-suppressive biological effects. Six healthy Beagle dogs were given 0.5, 1, 2, and 4 mg/kg prednisone orally once daily for 5 days, each successive course separated by a washout period of 9 days. At steady-state (Day 4), a sparse sampling design allowed for collection of blood from 2/6 individuals for each of the following time points: 0, 15, 30, 60, 90, 120, 240, 480, and 720 min. Prednisone and prednisolone were quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Oral prednisone was rapidly converted to prednisolone in dogs (≤ 30 min), with plasma prednisolone reaching ~6-fold greater levels (0–656.1 ng/mL) than prednisone (0–98.8 ng/mL) overall. The ratio of plasma prednisolone/prednisone was constant across the dosing regimens, indicating a non-saturation of the hepatic 11-β-hydroxysteroid dehydrogenase that converts the prodrug to the active metabolite in dogs. The level of both corticosteroids increased with increasing dosing regimens, albeit in a non-linear manner. Non-compartmental pharmacokinetic parameters are described, including peak concentration (Cmax), time of peak concentration (Tmax), area under the concentration-time curve (AUClast), and the elimination half-life (t 1/2) for both corticosteroids, as well as clearance and volume of distribution during the terminal phase (Vz) for the administered drug (prednisone). In sum, the present study utilizes a sparse sampling and naïve pooled-data approach to estimate pharmacokinetic parameters for prednisone and prednisolone, providing supporting preliminary knowledge that can be used to optimize corticosteroid efficacy and minimize toxicity in canine patients.This article is published as Sebbag, Lionel, and Jonathan P. Mochel. "Pharmacokinetics of oral prednisone at various doses in dogs: preliminary findings using a naïve pooled-data approach." Frontiers in Veterinary Science 7 (2020): 571457.
DOI: 10.3389/fvets.2020.571457.
Copyright 2020 Sebbag and Mochel.
Attribution 4.0 International (CC BY 4.0).
Posted with permission
Lionel Barrymore Collection - Accession 1716 M828 (885)
No full textThis collection consists of a framed watercolor painting titled, “Holiday Time in the South” by Lionel Barrymore. The nameplate states: “Painted And Presented To The Citizens Of Rock Hill As A Memento Of My Sincere Appreciation For Their Good Will Towards Me, 8-11-’53, Lionel Barrymore.” Also included in the collection are several photocopies of newspaper articles related to the receipt of the painting from 1953-1954 and a letter written by Lionel Barrymore on his letterhead to Miss Nan Weller Carson of the Rock Hill Public Library dated May 2, 1954. Lionel Barrymore (1878-1954) was a famous actor, director, author, and painter. A member of the Keystone Club of Rock Hill, Mrs. Eva M. White, wrote to Lionel as part of a project she was working on and Mr. Barrymore responded with a letter and telegram. In response, members of the Keystone Club sent several hundred letters and birthday cards to him for his 75th birthday. In thanks he painted and dedicated the watercolor, “Holiday Time in the South” to the City of Rock Hill.https://digitalcommons.winthrop.edu/manuscriptcollection_findingaids/2684/thumbnail.jp
An eye on the dog as the scientist's best friend for translational research in ophthalmology: Focus on the ocular surface
No full textPreclinical animal studies provide valuable opportunities to better understand human diseases and contribute to major advances in medicine. This review provides a comprehensive overview of ocular parameters in humans and selected animals, with a focus on the ocular surface, detailing species differences in ocular surface anatomy, physiology, tear film dynamics and tear film composition. We describe major pitfalls that tremendously limit the translational potential of traditional laboratory animals (i.e., rabbits, mice, and rats) in ophthalmic research, and highlight the benefits of integrating companion dogs with clinical analogues to human diseases into preclinical pharmacology studies. This One Health approach can help accelerate and improve the framework in which ophthalmic research is translated to the human clinic. Studies can be conducted in canine subjects with naturally occurring or noninvasively induced ocular surface disorders (e.g., dry eye disease, conjunctivitis), reviewed herein, and tear fluid can be easily retrieved from canine eyes for various bioanalytical purposes. In this review, we discuss common tear collection methods, including capillary tubes and Schirmer tear strips, and provide guidelines for tear sampling and extraction to improve the reliability of analyte quantification (drugs, proteins, others).This is the peer-reviewed version of the following article: Sebbag, Lionel, and Jonathan P. Mochel. "An Eye on the Dog as the Scientist’s Best Friend for Translational Research in Ophthalmology: Focus on the Ocular Surface." Medicinal Research Reviews (2020), which has been published in final form at DOI: 10.1002/med.21716. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Posted with permission.</p
Incidence of concurrent systemic injuries with traumatic proptosis and its effect on outcome – 100 dogs
No full textObjective: To evaluate the incidence of concurrent systemic injuries in dogs with traumatic ocular proptosis and their effect on survival to discharge. Additionally, to evaluate for associations between the type of trauma, each presenting vital signs, minimum laboratory database findings including packed cell volume, total solids, plasma glucose and lactate concentrations, and the diagnosis of concurrent systemic injury and survival.
Design: Retrospective study between the years 2017 and 2022.
Setting: One university teaching hospital and one large, private practice.
Animals: One hundred dogs presenting to the hospital with a diagnosis of traumatic ocular proptosis.
Measurements and main results: Medical records were retrospectively reviewed; signalment, breed, sex, age, weight, date of presentation, type of trauma sustained, time from trauma to presentation, vitals on presentation, and minimum laboratory database findings including packed cell volume (PCV), total solids (TS), plasma glucose concentration, and plasma lactate concentration were recorded. A modified animal trauma triage (ATT) score was retrospectively calculated. A total of 17 dogs (17%) had concurrent systemic injury. Compared to dogs without systemic injuries, dogs with systemic injuries had a significantly lower body temperature [median 101.1F (38.3C) vs. 101.6F (38.6C); P = 0.008], significantly higher plasma glucose concentrations (125 mg/dL, 6.9 mmol/L vs. 112 mg/dL, 6.2 mmol/L; P = 0.012) and approaching statistical significance, lower PCV values (median 40 vs. 46%; P = 0.051).
Conclusions: Dogs presenting with traumatic ocular proptosis do present with concurrent systemic, non-ocular injuries; however, these concurrent injuries do not seem to be associated with survival to discharge.This article is published as Whinery, Nicole, Rachel A. Allbaugh, Lionel Sebbag, and Rebecca Walton. "Incidence of concurrent systemic injuries and outcome with traumatic proptosis-100 dogs." Frontiers in Veterinary Science 10: 1271189. doi: https://doi.org/10.3389/fvets.2023.1271189. © 2024 Whinery, Allbaugh, Sebbag and Walton. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY)
Tear Film Pharmacokinetics and Systemic Absorption Following Topical Administration of 1% Prednisolone Acetate Ophthalmic Suspension in Dogs
No full textThe study aimed to determine the tear film pharmacokinetics following topical administration of 1% prednisolone acetate—assessing whether two drops would provide a superior kinetic profile compared to one drop—and to determine the fraction of an eye drop that reaches the systemic circulation in dogs. Two separate experiments were conducted in eight healthy Beagle dogs: (i) Instillation of 1 drop (35 μL) or 2 drops (70 μL) of 1% prednisolone acetate ophthalmic suspension in each eye, followed by tear collections with Schirmer strips from 0 to 720 min; (ii) Instillation of 1 or 2 drops of 1% prednisolone acetate in both eyes 4 times daily for 3 days, followed by blood collection 10–15 min after each topical administration on Day 3. Tear and blood samples were analyzed with high performance liquid chromatography to determine the levels of prodrug (prednisolone acetate), active metabolite (prednisolone) and total prednisolone (prednisolonetotal = prodrug + active metabolite). Prednisolone levels represented 10 and 72% of prednisolonetotal concentrations in tears and plasma, respectively, indicating a greater hydrolysis of prodrug in the blood vs. tear compartment. For eyes receiving one or two drops, tear film prednisolonetotal concentrations were high (~3.1 mg/mL) immediately following topical administration but rapidly decreased by ~45% at 1 min and ~95% at 15 min. No differences were noted between 1 vs. 2 drops in tear film prednisolonetotal concentrations (including maximal concentration, Cmax) or residual drug levels in tears at any time point (P ≥ 0.097); however, instillation of 2 drops provided a higher average tear concentration (Cavg) and overall drug exposure to the ocular surface (AUClast) over the 12-h sampling period (P = 0.009). Average plasma prednisolonetotal concentration represented ≤ 2% of the dose applied to the ocular surface, and did not differ significantly for dogs receiving 1 drop (17 ng/mL) or 2 drops (20 ng/mL) 4 times daily for 3 days (P = 0.438). In sum, topical corticotherapy is beneficial for inflammatory conditions of the canine anterior segment given the relatively high concentrations achieved in tears, although caution is warranted to prevent unwanted local or systemic adverse effects.This article is published as Sebbag, Lionel, Nicolette S. Kirner, Larry W. Wulf, and Jonathan P. Mochel. "Tear film pharmacokinetics and systemic absorption following topical administration of 1% prednisolone acetate ophthalmic suspension in dogs." Frontiers in Veterinary Science 7 (2020): 571350.
DOI: 10.3389/fvets.2020.571350.
Copyright 2020 Sebbag, Kirner, Wulf and Mochel.
Attribution 4.0 International (CC BY 4.0).
Posted with permission
Prevalence and Antibiotic Susceptibility of Bacterial Isolates From Dogs With Ulcerative Keratitis in Midwestern United States
No full textThe objective of this study was to describe bacterial culture and antibiotic susceptibility results in 476 dogs presenting with suspected bacterial keratitis in Iowa and surrounding Midwestern states, further detailing trends in patient characteristics, seasonality, and antimicrobial resistance. Corneal swabs yielded 465 bacterial isolates and 220 cultures (46.2%) with no apparent growth (0–5 isolates per culture). The most frequent bacterial genera were Staphylococcus (32.3%), Streptococcus (19.1%), and Pseudomonas (12.5%), while the most common bacterial species were Staphylococcus pseudintermedius (26.7%), Streptococcus canis (12%), and Pseudomonas aeruginosa (7.5%). Compared to mixed-breed dogs, canine breeds most likely to be examined for ulcerative keratitis included Boston terrier, Cavalier King Charles spaniel, miniature pinscher, pug, rat terrier, Saint Bernard, shih tzu, and silky terriers. In summer, the likelihood to yield a negative culture was reduced while the likelihood to culture Pseudomonas species was increased. Bacteria considered multidrug resistant (MDR, resistant to ≥ 3 antibiotic classes) represented 20% of all canine isolates and were most prevalent for Staphylococcus species (33%). An alarming, escalating trend of MDR prevalence was noted between 2016 (5%) and 2020 (34%). Individual ophthalmic preparations (i.e., single antibiotics or commercially available antibiotic combinations) with highest efficacy against all bacterial isolates included chloramphenicol (83%), ceftiofur (79%), amikacin (77%), neomycin-polymyxin B-bacitracin (77%), and gentamicin (74%). Efficacy of systemic antibiotics and combinations of ophthalmic preparations was also evaluated. Based on the present findings, triple antibiotic (Neo-Poly-Bac) is recommended as empirical monotherapy for prophylactic antibiotic therapy in dogs with simple corneal ulcers, while a chloramphenicol-ciprofloxacin combination is empirically recommended for therapeutic management of infected corneal ulcers. Pending culture and susceptibility results, appropriate selection of empiric antibiotic therapy is important to enhance therapeutic outcome and reduce antibacterial resistance in dogs with corneal ulceration.This article is published as Hewitt, Joshua S., Rachel A. Allbaugh, Danielle E. Kenne, and Lionel Sebbag. "Prevalence and antibiotic susceptibility of bacterial isolates from dogs with ulcerative keratitis in Midwestern United States." Frontiers in Veterinary Science 7 (2020): 583965.
DOI: 10.3389/fvets.2020.583965.
Copyright 2020 Hewitt, Allbaugh, Kenne and Sebbag.
Attribution 4.0 International (CC BY 4.0).
Posted with permission
Letter to the Editor: McKeever et al. 2021
No full textThank you to Drs. McKeever, Ward, and Hendrix for their recent report on canine bacterial keratitis and evaluation of antimicrobial resistance (10.1111/vop.12897).1 This is an important area that warrants closer examination given the importance of antimicrobial stewardship across species; however, there are several key errors with the interpretation of the antimicrobial resistance data that should be addressed. Because these errors are increasingly common in the veterinary literature, we are writing this letter to make the authors and readers aware of these issues to help improve analysis and reporting methods in the future.This letter is published as Kreuder AJ, Allbaugh RA, Sebbag L. Letter to the Editor: McKeever et al. 2021. Veterinary Ophthalmology. 2021 Nov;24(6):659-660. doi: https://doi.org/10.1111/vop.12934
Aqueous tear assessment in dogs: Impact of cephalic conformation, inter‐test correlations, and test‐retest repeatability
No full textObjective - To characterize diagnostic findings, test‐retest repeatability, and correlations among lacrimal tests in dogs of diverse cephalic conformations.
Animal studied - Fifty healthy dogs (25 brachycephalic, 25 nonbrachycephalic).
Procedures - A series of diagnostics were performed in each dog, allowing for a 10‐minute interval between tests and repeating each test 24 hours later under similar conditions: corneal tactile sensation (CTS), strip meniscometry test (SMT), phenol red thread test (PRTT), endodontic absorbent paper point tear test (EAPPTT), Schirmer tear test‐1 without (STT‐1) or with nasolacrimal stimulation (NL‐STT1), and Schirmer tear test‐2 (STT‐2).
Results - Mean ± SD test values were lower in brachycephalic vs. nonbrachycephalic dogs (except for SMT; 7.4 ± 2.0 mm/5 seconds vs 7.3 ± 2.4 mm/5 seconds), with statistically significant differences noted for CTS (1.8 ± 0.5 cm vs 3.4 ± 0.8 cm), PRTT (37.2 ± 4.0 mm/15 seconds vs 41.1 ± 5.5 mm/15 seconds), STT‐1 (20.1 ± 3.4 mm/min vs 23.3 ± 5.7 mm/min), STT‐2 (13.0 ± 3.4 mm/min vs 16.9 ± 3.9 mm/min), and NL‐STT1 (23.2 ± 3.6 mm/min vs 27.1 ± 5.4 mm/min), and nonsignificant differences for EAPPTT (16.6 ± 2.7 mm/15 seconds vs 17.5 ± 2.9 mm/15 seconds). Nasolacrimal stimulation increased STT‐1 values by 18% on average. Correlations among tests were generally weak to moderate (r
Conclusions - Corneal sensitivity and aqueous tear secretion are lower in brachycephalic dogs. A comprehensive assessment of the ocular surface requires the combination of several diagnostic tests. The nasolacrimal reflex may provide a useful diagnostic and therapeutic tool in dogs.This is the peer-reviewed version of the following article: Bolzanni, Hellen, Arianne P. Oriá, Ana Claudia S. Raposo, and Lionel Sebbag. "Aqueous tear assessment in dogs: Impact of cephalic conformation, inter‐test correlations, and test‐retest repeatability." Veterinary Ophthalmology (2020), which has been published in final form at DOI: 10.1111/vop.12751. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Posted with permission.</p
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