In veterinary ophthalmology, the retinoscope is primarily used for refractive examination, and reports of the examination with an autorefractometer are rare. In this study, we investigated the accuracy of a hand-held autorefractometer and the influence of accommodative palsy for results of refractive examination for dogs' eyes.
Forty six eyes of 23 laboratory Beagles were assessed. Refractive error (sphere error) was examined with a retinoscope and an autorefractometer (Retinomax K-plus; Nikon) before and after instillation of cycloplegic agent. To evaluate the consistency between retinoscopy and autorefractometry, Student's t-test, Pearson product-moment correlation coefficient, and Bland-Altman analysis were carried out. Student's t-test was also used to evaluate the influence of accommodative palsy.
The values with autorefractometry were significant lower and toward myopia than those with retinoscopy in subject's eyes with and without cycloplegia. In regression analysis, a weak correlation was found in non-cycloplegic eyes. Bland-Altman analysis showed that 45.7% of plotted points were within acceptable clinical range (±0.5 D) in non-cycloplegic eyes, versus 52.2% in cycloplegic eyes, and the autorefractometer was evaluated as being insufficient for a clinical alternative. In comparisons of the refractive values between non-cycloplegic and cycloplegic eyes, those values in cycloplegic eyes were significant higher and toward hyperopia than those of non-cycloplegic eyes on both methods.
It is cleared that hand-held autorefractometers like the Retinomax K-plus should be used with great cautions when the refractive error of dog's eyes is evaluated accurately. It is considered that autorefractometry after cycloplegic agent is an ideal way to minimize the changes of refractive value by accommodation.

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The aim of this study was to investigate the effects of histamine on the pupil margins of an isolated porcine iris by charge-coupled device (CCD) camera-based analysis. A fresh piece of iris tissue that included the papillary border was kept at 37°C in a 35-mm culture dish containing oxygenated Hank's balanced salt solution with glucose (final concentration, 5 g/L) and calcium chloride (final concentration, 0.56 g/L) and was exposed to histamine for 3 minutes. The degree of pupil margin constriction was calculated from images recorded on a CCD camera. Dose-response showed that histamine-induced margin constriction was observed at histamine concentrations ranging from 1 × 10^-8 to 1 × 10^-4 M. The pupil margin constriction induced by 1 × 10^-5 M histamine was not antagonized by cimetidine and famotidine (H₂-receptor antagonists), and atropine. However, the histamine-induced constriction was antagonized by chlorpheniramine (H₁-receptor antagonist).
Thus, the CCD camera-based analysis aided in investigating histamine-induced constriction of the pupil.

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To investigate for influence of the age of the month on electroretinogram (ERG) in beagle dogs, ERG was recorded in 20 beagle dogs (10 males and 10 females) at 6, 7, 9, 12, 16 and 18 months. ERG was recorded on the six light stimulation conditions, recommended by the International Society of Clinical Electrophysiology of Vision. As a result, the change of latency and amplitude was not seen at any age of the month. The ERG on the beagle dogs from 6 to 18 months was not influenced by the age of the month.

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Optical coherence tomography (OCT) is an analytical technique which enables non-invasive cross sectional imaging of the ocular fundus by computing wave intensity and positional information from the interference of the light reflected from bordering regions of different tissue density with that from the original light source when the fundal region is exposed to low-coherence near infra-red light¹⁾.
The cynomolgus monkey is widely used for safety evaluation in drug development and, with its macula lutea resembling those of humans, there are abundant background data on the evaluation of ophthalmic toxicity in this species. When ocular fundal abnormalities are to be investigated, examinations can be made with an aspheric lens and indirect ophthalmoscope. However, a considerable degree of proficiency is necessary to gain an understanding of the three-dimensional positional relationship for all tissue layers of the ocular fundus. Furthermore, it is difficult specify to the locations of small abnormalities.
We investigated the application of OCT by taking tomographic images of the ocular fundi of cynomolgus monkeys with macular and peripheral macular degeneration for a comparison with normal cynomolgus monkey. In addition, we report on a comparison of OCT and electroretinography (ERG) in the cynomolgus monkey.

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Microphthalmia and a raised focus with cystic appearance at the junction of cornea and conjunctiva were observed in the right eye of a male Crl:CD(SD) rat. Ophthalmological examination revealed corneal opacity and vascularization around the raised focus, and persistent hyperplastic primary vitreous (PHPV) in the vitreous body nearby the raised focus. Histopathological examination revealed that the raised focus showed cystic structure composed of scleral components, and diagnosed as scleral staphyloma. It was considered that scleral staphyloma in this case was incidentally formed accompanying with congenital lesions such as microphthalmia.

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