Antimicrobial susceptibility and minimal inhibitory concentration of Pseudomonas aeruginosa isolated from septic ocular surface disease in different animal species.

The purpose of this study was to evaluate the antibiotic susceptibility profile of Pseudomonas aeruginosa isolated from different animal species with septic ocular surface disease. Sixteen strains of P. aeruginosa were isolated from different species of animals (dog, cat, horse, penguin and brown bear) with ocular surface diseases such as conjunctivitis, keratocojnuctivits sicca and ulcerative keratitis. These isolates were tested against 11 different antimicrobials agents using the Kirby-Bauer disk-diffusion method. Minimum inhibitory concentrations (MICs) were determined using E-tests for two antibiotics (tobramycin and ciprofloxacin) commonly used in veterinary ophthalmology practice. Imipenem was the most effective antibiotic, with 100% of the strains being susceptible, followed by amikacin (87.5%), gentamicin, norfloxacin, gatifloxacin and polymyxin (both with 81.5%of susceptibility). MIC90 of ciprofloxacin was 2 µg/ml and the values found ranged from 0.094 µg/ml to 32 µg/ml. For tobramycin, MIC90 was 32 µg/ml and ranged from 0.25 µg/ml to 256 µg/ml. The most effective in vitro antibiotic tested against P. aeruginosa in this study was imipenem, followed by amikacin. The 3 mg/ml eye drops commercially available ciprofloxacin presentations were in vitro effective against all strains tested in this study if applied up to 4 hours after instillation. Whereas for tobramycin the 3 mg/ml eye drops commercial presentations were not in vitro effective against some strains isolated in this study. Thus for ocular infections with P. aeruginosa when using tobramycin the ideal recommendation would be to either use eye drops with higher concentrations or decrease the frequency intervals from four to a minimum of every two hours.

The eye of the Barbary sheep or aoudad (Ammotragus lervia): reference values for selected ophthalmic diagnostic tests, morphologic and biometric observations.

The purpose of this study was to describe the normal ocular anatomy and establish reference values for ophthalmic tests in the Barbary sheep or aoudad (Ammotragus lervia). Aoudad eyes are large and laterally positioned in the head with several specialized anatomic features attributed to evolutionary adaptations for grazing. Normal values for commonly used ophthalmic tests were established, Schirmer tear test (STT) - 27.22 ± 3.6 mm/min; Predominant ocular surface bacterial microbiota - Staphylococcus sp.; Corneal esthesiometry- 1.3 ± 0.4 cm; Intraocular pressure by rebound tonometry- 19.47 ± 3.9 mmHg; Corneal thickness- 630.07 ± 20.67 µm, B-mode ultrasonography of the globe-axial eye globe length 29.94 ± 0.96 mm, anterior chamber depth 5.03 ± 0.17 mm, lens thickness 9.4 ± 0.33 mm, vitreous chamber depth 14.1 ± 0.53 mm; Corneal diameter-horizontal corneal diameter 25.05 ± 2.18 mm, vertical corneal diameter 17.95 ± 1.68 mm; Horizontal palpebral fissure length- 34.8 ± 3.12 mm. Knowledge of these normal anatomic variations, biometric findings and normal parameters for ocular diagnostic tests may assist veterinary ophthalmologists in the diagnosis of ocular diseases in this and other similar species.

Ecobiometria ocular de cães glaucomatosos / Ocular echobiometry in glaucomatosus dogs

Foram estudados olhos glaucomatosos de cães referidos no serviço de diagnóstico por imagem. Os pacientes foram submetidos à ultrassonografia em modo B de alta resolução para realização de biometria ocular, por meio da qual foram realizadas as seguintes medidas: espessura central da córnea, profundidade da câmara anterior, espessura da lente e profundidade da câmara vítrea. Para tal, foi realizada contenção física e instilado colírio anestésico. Foram aferidas a PIO e a paquimetria da córnea e, em seguida, foi realizada a ultrassonografia em modo B nos dois olhos. Além da diferença óbvia de PIO, maior nos bulbos glaucomatosos, os resultados mostraram-se estatisticamente significativos em dois parâmetros: aumento da profundidade da câmara vítrea nos casos de glaucoma crônico (1,24±0,26cm; P=0,01) quando se comparou aos olhos controle e aumento da espessura da córnea também nos casos de glaucoma agudo (0,987±0,28cm; P=0,027), quando se comparou aos olhos controle e aos olhos com glaucoma crônico. Observou-se que a câmara vítrea é a estrutura intraocular que mais contribui no processo de expansão de volume do bulbo (buftalmia) durante o glaucoma...

Dogs with glaucomatous eyes referred to the Diagnostic Image Service at the Veterinary Hospital in the Federal University of Parana were studied using B-mode ultrasonography. Patients were submitted to a high resolution B-mode ultrasonography examination in order to perform ocular echobiometry. The following measurements were performed: central corneal thickness, anterior chamber depth, lens thickness and vitreous chamber depth. Physical restraint was performed and anesthetic eye drops were used. Corneal pachymetry and IOP were evaluated first and then B-mode ultrasonography was carried out in both eyes. Besides an obvious difference in IOP, which is higher in glaucomatous eyes, vitreous chamber depth significantly increases in cases of chronic glaucomatous eyes (1.24±0.26cm P=0.01), when compared to control eyes; and corneal thickness also increases in cases of acute glaucoma (0.987±0.28cm P=0.027), when compared to control eyes and to chronic glaucomatous eyeballs as well. Vitreous chamber is the intraocular structure that most contributes to the process of volume expansion of the globe (buphthalmos)...

Transitional carcinoma with extensive invasion of the bony orbit in a dog / Carcinoma transicional com invasão dos ossos da órbita em um cão

A 12-year-old male English Pointer was examined due to a soft-tissue swelling at the medial canthus of the right orbital region, which was causing facial deformity. The dog had epiphora, purulent nasal discharge, epistaxis, dyspnea, and progressive weight loss. An intraoral mass was observed near the right maxillary premolars. Neoplastic disease was diagnosed based on ancillary tests, which included blood work, skull and intraoral radiographs, ocular ultrasonography and computed tomography. Histopathology revealed transitional carcinoma involving the nasal and oral cavities, maxilla, bony orbit and retrobulbar space. Nasal tumors represent approximately 2% of all tumors diagnosed in this species. Transitional carcinoma is the second most common type of malignant epithelial tumor in the nasal sinuses. This case illustrates the extensive destruction of the soft and bony tissues of the face, including the bony orbit that this type of tumor can cause.

Um cão da raça Pointer Inglês, de 12 anos de idade, foi encaminhado para avaliação clínica por apresentar aumento de volume no canto temporal (medial) da órbita direita, o qual estava causando deformidade facial. O cão apresentava epífora, secreção nasal mucopurulenta, epistaxe, dispnésia e perda de peso progressiva. Uma massa foi observada na cavidade oral, próxima aos dentes pré-molares, do lado direito da face. Suspeitou-se de proliferação neoplásica baseando-se nos testes auxiliares, entre os quais: radiografia craniana e oral, ultrassonografia ocular e tomografia computadorizada. A análise histopatológica da massa revelou tratar-se de carcinoma transicional envolvendo as cavidades oral e nasal, os ossos da maxila e da órbita, além do espaço retrobulbar. Os tumores da cavidade nasal representam aproximadamente 2% de todos os tumores diagnosticados nessa espécie. O carcinoma transicional é o segundo tipo de neoplasia epitelial maligna mais comum nos seios nasais de cães. Este trabalho descreve a destruição extensiva dos tecidos moles e dos ossos da face e chama atenção para o fato de que esse tipo de neoplasia deve ser considerado nas doenças da órbita.

Electroretinography in dogs using a fiber electrode prototype.

We compared two electroretinography (ERG) electrodes in dogs using ERG standards of the International Society for Clinical Electrophysiology of Vision (ISCEV). Ten healthy Yorkshire terrier dogs (mean age, 2.80 ± 1.42 years; 6 females) weighing 5.20 ± 1.56 kg were evaluated using an ERG system for veterinary use. Dark- and light-adapted ERG responses were recorded using an ERG-Jet electrode and a fiber electrode prototype. The examinations were performed during 2 visits, 3 weeks apart. Both electrodes (ERG-Jet or fiber prototype) were used on each animal and the first eye to be recorded (OD × OS) was selected randomly. Three weeks later the examination was repeated on the same animal switching the type of electrode to be used that day and the first eye to be examined. The magnitude and waveform quality obtained with the two electrode types were similar for all ERG responses. ERG amplitudes and implicit times obtained from dogs using the fiber electrode prototype were comparable to those obtained with the ERG-Jet electrode for rod, maximal rod-cone summed, cone, and 30-Hz flicker responses. The fiber electrode prototype is a low-cost device, available as an alternative instrument for clinical veterinary ERG recording for retinal function assessment.

Electroretinography in dogs using a fiber electrode prototype

We compared two electroretinography (ERG) electrodes in dogs using ERG standards of the International Society for Clinical Electrophysiology of Vision (ISCEV). Ten healthy Yorkshire terrier dogs (mean age, 2.80 ± 1.42 years; 6 females) weighing 5.20 ± 1.56 kg were evaluated using an ERG system for veterinary use. Dark- and light-adapted ERG responses were recorded using an ERG-Jet electrode and a fiber electrode prototype. The examinations were performed during 2 visits, 3 weeks apart. Both electrodes (ERG-Jet or fiber prototype) were used on each animal and the first eye to be recorded (OD × OS) was selected randomly. Three weeks later the examination was repeated on the same animal switching the type of electrode to be used that day and the first eye to be examined. The magnitude and waveform quality obtained with the two electrode types were similar for all ERG responses. ERG amplitudes and implicit times obtained from dogs using the fiber electrode prototype were comparable to those obtained with the ERG-Jet electrode for rod, maximal rod-cone summed, cone, and 30-Hz flicker responses. The fiber electrode prototype is a low-cost device, available as an alternative instrument for clinical veterinary ERG recording for retinal function assessment.

Spontaneous lacquer crack lesions in the retinopathy, globe enlarged (rge) chick.

Lacquer crack lesion (LCL), a complication of myopia in human patients, is characterized by loss of retinal pigment epithelium and breaks in Bruch's membrane. This report describes comparable lesions in the "retinopathy, globe enlarged" (rge) chick. Twenty-six birds, (nine rge/rge [affected], 12 rge/+ [carriers] and five +/+ [normal]), were examined ophthalmoscopically from hatching up to 336 days of age. Ophthalmoscopically detected fundus lesions were investigated by light and transmission electron microscopy. Pale, linear fundus lesions were detected in both eyes of seven of the nine rge/rge chicks, from as early as 45 days of age. Histological and ultrastructural examination of four of the affected rge/rge chicks revealed areas of ruptured Bruch's membrane, with focal absence of retinal pigment epithelium. Fibroblasts covered the interface of the abnormal Bruch's membrane and choriocapillaris. There was disorganization of overlying photoreceptor outer and inner segments, and thinning of inner and outer nuclear layers, while the rest of the inner retina appeared unaltered. The lesions present in rge chicks showed histological changes similar to those of LCLs described in human patients with pathological myopia. The formation of LCLs in rge chicks is probably due to stretching of Bruch's membrane secondary to abnormal globe enlargement, resulting in linear rupture of the membrane and associated changes. The rge chick may prove a useful model for human LCL formation.

Basic concepts in statistics for veterinary ophthalmologists.

Abstract This review article provides a comprehensive coverage of basic statistical procedures commonly used in biologic experiments and is intended to be a basic guide to the selection of appropriate tests and also to aid the reader in the evaluation of published studies. The focus is on the use, interpretation and presentation of the main statistical tests and their key concepts for the practicing veterinary ophthalmologist. Several examples derived from actual ophthalmic research are presented in the text. Lastly, the article discusses computer-based statistical analysis, provides a list of different software available and gives a practical example of a 'real life' statistical analysis.